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Re: One engine down...looking for solutions/suggestions

 

I think there are two issues that electric yachters have to address and the answers will likely be different for different kinds of users.

?

1: What is the fastest speed I can go and for how long?

Speed and draw are not linear. You might triple the draw to double the speed. And of course at some point "going faster" becomes impractical regardless of how the motor is powered.

You'll want to figure out how fast you NEED to be able to go and for how long, and then work backwards to find a motor that can deliver that much power, and then work backwards to figure out how big a bank of batteries you'll need to support that load.

I suspect this is much more complicated for a cat than a monohull.

?

2: What is the longest time you want to be able to run the motor at a SOG you consider acceptable?

There will be a point on the graph of speed and power draw where the boat is moving fast enough to be acceptable, and the draw is low enough to allow a fairly extended range. Once you determine that point, you can extrapolate how big a bank of batteries you will want to have to determine the distances you can cross with the motor. Practically speaking, that is going to be somewhere around 40nm in flat seas with no wind. If you have requirements to be able to motor a longer distance you'll have to look at extraordinarily large battery banks, or battery options that will take you away from LiFePo4.

?

Compounding this analysis is the idea that the prop size for an electric motor may not be the same size as for a diesel, and you may want to try and do regen while sailing which likely means you won't use a folding prop.

?

The final thing you need to consider is how to charge the battery bank. If you want to rely on solar you'll need to think about how much solar you can install on your boat. You can make about 7.5A at 48V per 100W of solar per day for an "average day". If you had a 400A bank and you wanted to charge the bank in one day, you'd need 5,300W of solar.

You might want to install a generator for the purpose of charging the batteries. That means you will still have to keep fuel storage and polishing, exhaust, and other systems for that motor, and you'll still be doing routine maintenance; but you may do a lot less depending on how much you have to run that generator.


Re: Draft Schematic-Please give input

 

开云体育

Any voltage system above 50V is very hard to get boat insurance for.

Kai

On 30 Apr 2021, at 19:53, Ryan Sweet <ryan@...> wrote:

?
I guess that’s my point is if the system is capable of 96v its a different thing and should be treated as such. ?IIUC, Morris like the me1515 etc are most efficient at the higher end of their voltage range. I think the reason most of us want to keep things at 48v is that the simplicity of the system and the cost of the batteries makes it worth the efficiency trade off and lower max power.?

On Apr 30, 2021, at 11:46, Jeff LaCoursiere <jeff@...> wrote:

? Above 50v there are safety considerations that most DIY folks aren't ready or willing to entertain...? I think even some regulations? Anyone know more about that?

Cheers,

Jeff LaCoursiere
s/v Angels Quest


On 4/30/21 1:42 PM, Ryan Sweet wrote:
The other thing about 48v vs 96v is really why not just run at 96v the whole time. Basically if you are making it possible then all the rest of the system has to be specd to 96v and I don’t see the reason to not keep it that way??

On Apr 30, 2021, at 11:12, Ryan Sweet via groups.io <ryan@...> wrote:

?

On Apr 30, 2021, at 9:38 AM, Carsten via <Carstensemail@...> wrote:

Another thing, how about making the motor wattage output adjustable, so it is possible to use eg. 96V for a burst mode ? Many 48V motors can be powered by 96V (or higher).
I assume that the wiring can handle that. Making two sets of banks 48V, to be serial connected to 96V.
The short "event" should of course be managed by the BMS/power management system.


This is interesting and something Ive wondered about but from what I’ve been able to discern it requires dynamically reprogramming the motor controller. ?You could imagine a switching setup that let you have 48v traction banks in parallel but then to change them to series. ?I wasn’t able to figure out a way to use the Seven Gen4 to do this kind of thing, at least from reading the manual. ?I fear I am about to venture into the world of the DVT software though and maybe its capable of that. I suppose if a person spent enough on controllers and cables you could have a dual system with two controllers and switch between them but I think you approach the point of diminishing returns.?

However, it points to a possible opportunity or maybe just a future feature that advanced motor controllers will enable. ?With EV regen becoming more popular in controllers, I would not be surprised if some battery management features also start to migrate to controllers as well.?

To be true, things made in China is not my cup of tea, but in these days, unfortunately simply unavoidable !
I was a supervisor in China for several years, and know how they make things, and all of QC is not like in the West.
Buy a ME1616 electromotor. Made in China, then sold in the West.
Buy yourself a german or US car. Half of the smaller parts in it are made in China by now.

Company supervisors are not in China now, because of the Made in China virus.
Who wants to spend 2-4 weeks in quarantine to go for an inspection ??
Who's checking the quality now ?

As I spin up my own commercial efforts I have been working with colleagues in CN to understand the quality dynamics and the manufacturing landscape and while I think some of these comments are in a general sense applicable, I think that the demands of growing sophistication in their domestic market, growing domestic regulatory regime, and a drive to differentiate by rising to the QC and supply chain standards of Korea, Japan, US, and Europe is pressuring a lot of CN companies to advance. ?I think now it is more a story of doing homework to understand your partners and their processes.

Now, the current chaos of the global shipping / logistics is another story! The Suez Canal incident has cost me several weeks and the knock-on effects will continue for months.?

However, I believe that new, checked, LiFePO4 batteries will last my sailing life out, but the electronics is another concern.
Especially in a marine environment (humid and salty).
Can you provide recommendations where to setup these (rather large) electronic regulators/inverters/BMS'es in the boat ?
I guess IP rating is not relevant, if not encapsuled in IP-rated boxes.
If put into boxes, then there's a cooling issue...

As far from any wet bilge or dripping shaft or outdoor moisture as possible. ?In the cabin if you can. If exposed to moist air frequently try running some electric air warmer/dryers or a dehumidifier (when on shore power).?


Working hard on the ultimate solution for my own EMS/Y system conversion design.

Cheers, guys
Carsten


Hint : EMS/Y = Electric Motor Sailing Yacht ;-)



On Friday, 30 April 2021, 02:46:25 GMT+8, Jeff LaCoursiere <jeff@...> wrote:


We haven't had any bad cells imported yet, knock wood.? We *are* doing our best to burn down our offices with our BMS experiments though :)? Also, our latest batch was all EVE 280AH cells, the Lishen 272AH are apparently "all gone".

Another cool idea we are kicking around... we want our 48v pack to have a 12v tap, so you can use it as your house battery as well as your traction battery.? I'm disappointed in the available downconverters, mostly current limited to 30-60A.? Maybe that would be enough for your house, but it wouldn't do it for mine.

So we want to try to cycle through internal banks of four cells, very quickly (like 10khz), connecting them in turn to the 12v tap.? We believe that this way you will be able to pull the full 1C discharge of the 16 cell pack (280A), but at 12v!? We hope to maintain balance in discharge by cycling very fast, but the BMS should pick up the slack.

Cheers,

Jeff LaCoursiere
s/v Angels Quest


On 4/29/21 11:34 AM, Carsten via wrote:
Hi, Jeff

Did you experience single/multiple cell dropouts from Lishen batteries so far ?

On Thursday, 29 April 2021, 23:22:13 GMT+8, Jeff LaCoursiere <jeff@...> wrote:



I wanted to comment on 1) below - we have that same concept in mind.? We are working on a BMS design that will basically allow cells to be "dropped out" of series, the output run through a boost circuit to maintain steady voltage.? There are of course limits to how many can drop out and we are very much at the experimental stage here, but there is some hope :)

Jeff LaCoursiere
s/v Angels Quest


On 4/29/21 10:06 AM, oreillygb@... wrote:
First Draft of Schematic. Using Lishen 202Ah. I decided to go with the BMS only actively controlling the charge side of the circuit and opted for passive monitoring on the load side. Using a victron 712 for monitoring and hopefully can connect it to a relay to shut off charge circuit at predetermined voltage. Guys please tell me what I have missed.

Couple of points.

1) Passive Load monitoring. I have decided to go this route as i understand that the load BMS can turn off for 2 reasons, obviously first is if whole bank drops to a lower than 20%SOC and secondly if single cells fail. From my perspective if I have a single cell failure I would rather still be able to use the other 15 cells than have no power. If I let my bank drop to below SOC of 20% that's?on me.
2) Want to keep house bank separate?for now, mainly as if I have to shut off my 48v bank for low SOC I don't want to have to worry about all my electronics being offline.
3) I want a separate?relay to shut off charge current so that I can set this manually. When I come back from a sail i want to be able to top bank up to about a 70% SOC for storage. Then on the day I want to sail I can top it off o 90%


-- 
Jeff LaCoursiere
StratusTalk, Inc.
703 496 4990 x108
815 546 6599 cell

--
Jeff LaCoursiere
s/v Angels Quest
St Thomas USVI

--

Jeff LaCoursiere
STRATUSTALK, INC. / CTO

Phone: +1 703.496.4990 x108
Mobile: +1 815.546.6599
Email: jeff@...
Website:
Address: One Freedom Square
13th Floor
Reston, VA 20190
? ? ?



--
Jeff LaCoursiere
s/v Angels Quest
St Thomas USVI


--

Jeff LaCoursiere
STRATUSTALK, INC. / CTO

Phone: +1 703.496.4990 x108
Mobile: +1 815.546.6599
Email: jeff@...
Website:
Address: One Freedom Square
13th Floor
Reston, VA 20190
? ? ?



--
Jeff LaCoursiere
s/v Angels Quest
St Thomas USVI


Re: Draft Schematic-Please give input

 

开云体育

s/Morris/motors/

Autocorrect is giving me a heck of a time today.?

On Apr 30, 2021, at 11:53, Ryan Sweet via groups.io <ryan@...> wrote:

?
I guess that’s my point is if the system is capable of 96v its a different thing and should be treated as such. ?IIUC, Morris like the me1515 etc are most efficient at the higher end of their voltage range. I think the reason most of us want to keep things at 48v is that the simplicity of the system and the cost of the batteries makes it worth the efficiency trade off and lower max power.?

On Apr 30, 2021, at 11:46, Jeff LaCoursiere <jeff@...> wrote:

? Above 50v there are safety considerations that most DIY folks aren't ready or willing to entertain...? I think even some regulations? Anyone know more about that?

Cheers,

Jeff LaCoursiere
s/v Angels Quest


On 4/30/21 1:42 PM, Ryan Sweet wrote:
The other thing about 48v vs 96v is really why not just run at 96v the whole time. Basically if you are making it possible then all the rest of the system has to be specd to 96v and I don’t see the reason to not keep it that way??

On Apr 30, 2021, at 11:12, Ryan Sweet via groups.io <ryan@...> wrote:

?

On Apr 30, 2021, at 9:38 AM, Carsten via <Carstensemail@...> wrote:

Another thing, how about making the motor wattage output adjustable, so it is possible to use eg. 96V for a burst mode ? Many 48V motors can be powered by 96V (or higher).
I assume that the wiring can handle that. Making two sets of banks 48V, to be serial connected to 96V.
The short "event" should of course be managed by the BMS/power management system.


This is interesting and something Ive wondered about but from what I’ve been able to discern it requires dynamically reprogramming the motor controller. ?You could imagine a switching setup that let you have 48v traction banks in parallel but then to change them to series. ?I wasn’t able to figure out a way to use the Seven Gen4 to do this kind of thing, at least from reading the manual. ?I fear I am about to venture into the world of the DVT software though and maybe its capable of that. I suppose if a person spent enough on controllers and cables you could have a dual system with two controllers and switch between them but I think you approach the point of diminishing returns.?

However, it points to a possible opportunity or maybe just a future feature that advanced motor controllers will enable. ?With EV regen becoming more popular in controllers, I would not be surprised if some battery management features also start to migrate to controllers as well.?

To be true, things made in China is not my cup of tea, but in these days, unfortunately simply unavoidable !
I was a supervisor in China for several years, and know how they make things, and all of QC is not like in the West.
Buy a ME1616 electromotor. Made in China, then sold in the West.
Buy yourself a german or US car. Half of the smaller parts in it are made in China by now.

Company supervisors are not in China now, because of the Made in China virus.
Who wants to spend 2-4 weeks in quarantine to go for an inspection ??
Who's checking the quality now ?

As I spin up my own commercial efforts I have been working with colleagues in CN to understand the quality dynamics and the manufacturing landscape and while I think some of these comments are in a general sense applicable, I think that the demands of growing sophistication in their domestic market, growing domestic regulatory regime, and a drive to differentiate by rising to the QC and supply chain standards of Korea, Japan, US, and Europe is pressuring a lot of CN companies to advance. ?I think now it is more a story of doing homework to understand your partners and their processes.

Now, the current chaos of the global shipping / logistics is another story! The Suez Canal incident has cost me several weeks and the knock-on effects will continue for months.?

However, I believe that new, checked, LiFePO4 batteries will last my sailing life out, but the electronics is another concern.
Especially in a marine environment (humid and salty).
Can you provide recommendations where to setup these (rather large) electronic regulators/inverters/BMS'es in the boat ?
I guess IP rating is not relevant, if not encapsuled in IP-rated boxes.
If put into boxes, then there's a cooling issue...

As far from any wet bilge or dripping shaft or outdoor moisture as possible. ?In the cabin if you can. If exposed to moist air frequently try running some electric air warmer/dryers or a dehumidifier (when on shore power).?


Working hard on the ultimate solution for my own EMS/Y system conversion design.

Cheers, guys
Carsten


Hint : EMS/Y = Electric Motor Sailing Yacht ;-)



On Friday, 30 April 2021, 02:46:25 GMT+8, Jeff LaCoursiere <jeff@...> wrote:


We haven't had any bad cells imported yet, knock wood.? We *are* doing our best to burn down our offices with our BMS experiments though :)? Also, our latest batch was all EVE 280AH cells, the Lishen 272AH are apparently "all gone".

Another cool idea we are kicking around... we want our 48v pack to have a 12v tap, so you can use it as your house battery as well as your traction battery.? I'm disappointed in the available downconverters, mostly current limited to 30-60A.? Maybe that would be enough for your house, but it wouldn't do it for mine.

So we want to try to cycle through internal banks of four cells, very quickly (like 10khz), connecting them in turn to the 12v tap.? We believe that this way you will be able to pull the full 1C discharge of the 16 cell pack (280A), but at 12v!? We hope to maintain balance in discharge by cycling very fast, but the BMS should pick up the slack.

Cheers,

Jeff LaCoursiere
s/v Angels Quest


On 4/29/21 11:34 AM, Carsten via wrote:
Hi, Jeff

Did you experience single/multiple cell dropouts from Lishen batteries so far ?

On Thursday, 29 April 2021, 23:22:13 GMT+8, Jeff LaCoursiere <jeff@...> wrote:



I wanted to comment on 1) below - we have that same concept in mind.? We are working on a BMS design that will basically allow cells to be "dropped out" of series, the output run through a boost circuit to maintain steady voltage.? There are of course limits to how many can drop out and we are very much at the experimental stage here, but there is some hope :)

Jeff LaCoursiere
s/v Angels Quest


On 4/29/21 10:06 AM, oreillygb@... wrote:
First Draft of Schematic. Using Lishen 202Ah. I decided to go with the BMS only actively controlling the charge side of the circuit and opted for passive monitoring on the load side. Using a victron 712 for monitoring and hopefully can connect it to a relay to shut off charge circuit at predetermined voltage. Guys please tell me what I have missed.

Couple of points.

1) Passive Load monitoring. I have decided to go this route as i understand that the load BMS can turn off for 2 reasons, obviously first is if whole bank drops to a lower than 20%SOC and secondly if single cells fail. From my perspective if I have a single cell failure I would rather still be able to use the other 15 cells than have no power. If I let my bank drop to below SOC of 20% that's?on me.
2) Want to keep house bank separate?for now, mainly as if I have to shut off my 48v bank for low SOC I don't want to have to worry about all my electronics being offline.
3) I want a separate?relay to shut off charge current so that I can set this manually. When I come back from a sail i want to be able to top bank up to about a 70% SOC for storage. Then on the day I want to sail I can top it off o 90%


-- 
Jeff LaCoursiere
StratusTalk, Inc.
703 496 4990 x108
815 546 6599 cell

--
Jeff LaCoursiere
s/v Angels Quest
St Thomas USVI

--

Jeff LaCoursiere
STRATUSTALK, INC. / CTO

Phone: +1 703.496.4990 x108
Mobile: +1 815.546.6599
Email: jeff@...
Website:
Address: One Freedom Square
13th Floor
Reston, VA 20190
? ? ?



--
Jeff LaCoursiere
s/v Angels Quest
St Thomas USVI


--

Jeff LaCoursiere
STRATUSTALK, INC. / CTO

Phone: +1 703.496.4990 x108
Mobile: +1 815.546.6599
Email: jeff@...
Website:
Address: One Freedom Square
13th Floor
Reston, VA 20190
? ? ?



--
Jeff LaCoursiere
s/v Angels Quest
St Thomas USVI


Re: Draft Schematic-Please give input

 

开云体育

I guess that’s my point is if the system is capable of 96v its a different thing and should be treated as such. ?IIUC, Morris like the me1515 etc are most efficient at the higher end of their voltage range. I think the reason most of us want to keep things at 48v is that the simplicity of the system and the cost of the batteries makes it worth the efficiency trade off and lower max power.?

On Apr 30, 2021, at 11:46, Jeff LaCoursiere <jeff@...> wrote:

? Above 50v there are safety considerations that most DIY folks aren't ready or willing to entertain...? I think even some regulations? Anyone know more about that?

Cheers,

Jeff LaCoursiere
s/v Angels Quest


On 4/30/21 1:42 PM, Ryan Sweet wrote:
The other thing about 48v vs 96v is really why not just run at 96v the whole time. Basically if you are making it possible then all the rest of the system has to be specd to 96v and I don’t see the reason to not keep it that way??

On Apr 30, 2021, at 11:12, Ryan Sweet via groups.io <ryan@...> wrote:

?

On Apr 30, 2021, at 9:38 AM, Carsten via <Carstensemail@...> wrote:

Another thing, how about making the motor wattage output adjustable, so it is possible to use eg. 96V for a burst mode ? Many 48V motors can be powered by 96V (or higher).
I assume that the wiring can handle that. Making two sets of banks 48V, to be serial connected to 96V.
The short "event" should of course be managed by the BMS/power management system.


This is interesting and something Ive wondered about but from what I’ve been able to discern it requires dynamically reprogramming the motor controller. ?You could imagine a switching setup that let you have 48v traction banks in parallel but then to change them to series. ?I wasn’t able to figure out a way to use the Seven Gen4 to do this kind of thing, at least from reading the manual. ?I fear I am about to venture into the world of the DVT software though and maybe its capable of that. I suppose if a person spent enough on controllers and cables you could have a dual system with two controllers and switch between them but I think you approach the point of diminishing returns.?

However, it points to a possible opportunity or maybe just a future feature that advanced motor controllers will enable. ?With EV regen becoming more popular in controllers, I would not be surprised if some battery management features also start to migrate to controllers as well.?

To be true, things made in China is not my cup of tea, but in these days, unfortunately simply unavoidable !
I was a supervisor in China for several years, and know how they make things, and all of QC is not like in the West.
Buy a ME1616 electromotor. Made in China, then sold in the West.
Buy yourself a german or US car. Half of the smaller parts in it are made in China by now.

Company supervisors are not in China now, because of the Made in China virus.
Who wants to spend 2-4 weeks in quarantine to go for an inspection ??
Who's checking the quality now ?

As I spin up my own commercial efforts I have been working with colleagues in CN to understand the quality dynamics and the manufacturing landscape and while I think some of these comments are in a general sense applicable, I think that the demands of growing sophistication in their domestic market, growing domestic regulatory regime, and a drive to differentiate by rising to the QC and supply chain standards of Korea, Japan, US, and Europe is pressuring a lot of CN companies to advance. ?I think now it is more a story of doing homework to understand your partners and their processes.

Now, the current chaos of the global shipping / logistics is another story! The Suez Canal incident has cost me several weeks and the knock-on effects will continue for months.?

However, I believe that new, checked, LiFePO4 batteries will last my sailing life out, but the electronics is another concern.
Especially in a marine environment (humid and salty).
Can you provide recommendations where to setup these (rather large) electronic regulators/inverters/BMS'es in the boat ?
I guess IP rating is not relevant, if not encapsuled in IP-rated boxes.
If put into boxes, then there's a cooling issue...

As far from any wet bilge or dripping shaft or outdoor moisture as possible. ?In the cabin if you can. If exposed to moist air frequently try running some electric air warmer/dryers or a dehumidifier (when on shore power).?


Working hard on the ultimate solution for my own EMS/Y system conversion design.

Cheers, guys
Carsten


Hint : EMS/Y = Electric Motor Sailing Yacht ;-)



On Friday, 30 April 2021, 02:46:25 GMT+8, Jeff LaCoursiere <jeff@...> wrote:


We haven't had any bad cells imported yet, knock wood.? We *are* doing our best to burn down our offices with our BMS experiments though :)? Also, our latest batch was all EVE 280AH cells, the Lishen 272AH are apparently "all gone".

Another cool idea we are kicking around... we want our 48v pack to have a 12v tap, so you can use it as your house battery as well as your traction battery.? I'm disappointed in the available downconverters, mostly current limited to 30-60A.? Maybe that would be enough for your house, but it wouldn't do it for mine.

So we want to try to cycle through internal banks of four cells, very quickly (like 10khz), connecting them in turn to the 12v tap.? We believe that this way you will be able to pull the full 1C discharge of the 16 cell pack (280A), but at 12v!? We hope to maintain balance in discharge by cycling very fast, but the BMS should pick up the slack.

Cheers,

Jeff LaCoursiere
s/v Angels Quest


On 4/29/21 11:34 AM, Carsten via wrote:
Hi, Jeff

Did you experience single/multiple cell dropouts from Lishen batteries so far ?

On Thursday, 29 April 2021, 23:22:13 GMT+8, Jeff LaCoursiere <jeff@...> wrote:



I wanted to comment on 1) below - we have that same concept in mind.? We are working on a BMS design that will basically allow cells to be "dropped out" of series, the output run through a boost circuit to maintain steady voltage.? There are of course limits to how many can drop out and we are very much at the experimental stage here, but there is some hope :)

Jeff LaCoursiere
s/v Angels Quest


On 4/29/21 10:06 AM, oreillygb@... wrote:
First Draft of Schematic. Using Lishen 202Ah. I decided to go with the BMS only actively controlling the charge side of the circuit and opted for passive monitoring on the load side. Using a victron 712 for monitoring and hopefully can connect it to a relay to shut off charge circuit at predetermined voltage. Guys please tell me what I have missed.

Couple of points.

1) Passive Load monitoring. I have decided to go this route as i understand that the load BMS can turn off for 2 reasons, obviously first is if whole bank drops to a lower than 20%SOC and secondly if single cells fail. From my perspective if I have a single cell failure I would rather still be able to use the other 15 cells than have no power. If I let my bank drop to below SOC of 20% that's?on me.
2) Want to keep house bank separate?for now, mainly as if I have to shut off my 48v bank for low SOC I don't want to have to worry about all my electronics being offline.
3) I want a separate?relay to shut off charge current so that I can set this manually. When I come back from a sail i want to be able to top bank up to about a 70% SOC for storage. Then on the day I want to sail I can top it off o 90%


-- 
Jeff LaCoursiere
StratusTalk, Inc.
703 496 4990 x108
815 546 6599 cell

--
Jeff LaCoursiere
s/v Angels Quest
St Thomas USVI

--

Jeff LaCoursiere
STRATUSTALK, INC. / CTO

Phone: +1 703.496.4990 x108
Mobile: +1 815.546.6599
Email: jeff@...
Website:
Address: One Freedom Square
13th Floor
Reston, VA 20190
? ? ?



--
Jeff LaCoursiere
s/v Angels Quest
St Thomas USVI


--

Jeff LaCoursiere
STRATUSTALK, INC. / CTO

Phone: +1 703.496.4990 x108
Mobile: +1 815.546.6599
Email: jeff@...
Website:
Address: One Freedom Square
13th Floor
Reston, VA 20190
? ? ?



--
Jeff LaCoursiere
s/v Angels Quest
St Thomas USVI


Re: Draft Schematic-Please give input

 

开云体育

Above 50v there are safety considerations that most DIY folks aren't ready or willing to entertain...? I think even some regulations? Anyone know more about that?

Cheers,

Jeff LaCoursiere
s/v Angels Quest


On 4/30/21 1:42 PM, Ryan Sweet wrote:
The other thing about 48v vs 96v is really why not just run at 96v the whole time. Basically if you are making it possible then all the rest of the system has to be specd to 96v and I don’t see the reason to not keep it that way??

On Apr 30, 2021, at 11:12, Ryan Sweet via groups.io <ryan@...> wrote:

?

On Apr 30, 2021, at 9:38 AM, Carsten via <Carstensemail@...> wrote:

Another thing, how about making the motor wattage output adjustable, so it is possible to use eg. 96V for a burst mode ? Many 48V motors can be powered by 96V (or higher).
I assume that the wiring can handle that. Making two sets of banks 48V, to be serial connected to 96V.
The short "event" should of course be managed by the BMS/power management system.


This is interesting and something Ive wondered about but from what I’ve been able to discern it requires dynamically reprogramming the motor controller. ?You could imagine a switching setup that let you have 48v traction banks in parallel but then to change them to series. ?I wasn’t able to figure out a way to use the Seven Gen4 to do this kind of thing, at least from reading the manual. ?I fear I am about to venture into the world of the DVT software though and maybe its capable of that. I suppose if a person spent enough on controllers and cables you could have a dual system with two controllers and switch between them but I think you approach the point of diminishing returns.?

However, it points to a possible opportunity or maybe just a future feature that advanced motor controllers will enable. ?With EV regen becoming more popular in controllers, I would not be surprised if some battery management features also start to migrate to controllers as well.?

To be true, things made in China is not my cup of tea, but in these days, unfortunately simply unavoidable !
I was a supervisor in China for several years, and know how they make things, and all of QC is not like in the West.
Buy a ME1616 electromotor. Made in China, then sold in the West.
Buy yourself a german or US car. Half of the smaller parts in it are made in China by now.

Company supervisors are not in China now, because of the Made in China virus.
Who wants to spend 2-4 weeks in quarantine to go for an inspection ??
Who's checking the quality now ?

As I spin up my own commercial efforts I have been working with colleagues in CN to understand the quality dynamics and the manufacturing landscape and while I think some of these comments are in a general sense applicable, I think that the demands of growing sophistication in their domestic market, growing domestic regulatory regime, and a drive to differentiate by rising to the QC and supply chain standards of Korea, Japan, US, and Europe is pressuring a lot of CN companies to advance. ?I think now it is more a story of doing homework to understand your partners and their processes.

Now, the current chaos of the global shipping / logistics is another story! The Suez Canal incident has cost me several weeks and the knock-on effects will continue for months.?

However, I believe that new, checked, LiFePO4 batteries will last my sailing life out, but the electronics is another concern.
Especially in a marine environment (humid and salty).
Can you provide recommendations where to setup these (rather large) electronic regulators/inverters/BMS'es in the boat ?
I guess IP rating is not relevant, if not encapsuled in IP-rated boxes.
If put into boxes, then there's a cooling issue...

As far from any wet bilge or dripping shaft or outdoor moisture as possible. ?In the cabin if you can. If exposed to moist air frequently try running some electric air warmer/dryers or a dehumidifier (when on shore power).?


Working hard on the ultimate solution for my own EMS/Y system conversion design.

Cheers, guys
Carsten


Hint : EMS/Y = Electric Motor Sailing Yacht ;-)



On Friday, 30 April 2021, 02:46:25 GMT+8, Jeff LaCoursiere <jeff@...> wrote:


We haven't had any bad cells imported yet, knock wood.? We *are* doing our best to burn down our offices with our BMS experiments though :)? Also, our latest batch was all EVE 280AH cells, the Lishen 272AH are apparently "all gone".

Another cool idea we are kicking around... we want our 48v pack to have a 12v tap, so you can use it as your house battery as well as your traction battery.? I'm disappointed in the available downconverters, mostly current limited to 30-60A.? Maybe that would be enough for your house, but it wouldn't do it for mine.

So we want to try to cycle through internal banks of four cells, very quickly (like 10khz), connecting them in turn to the 12v tap.? We believe that this way you will be able to pull the full 1C discharge of the 16 cell pack (280A), but at 12v!? We hope to maintain balance in discharge by cycling very fast, but the BMS should pick up the slack.

Cheers,

Jeff LaCoursiere
s/v Angels Quest


On 4/29/21 11:34 AM, Carsten via wrote:
Hi, Jeff

Did you experience single/multiple cell dropouts from Lishen batteries so far ?

On Thursday, 29 April 2021, 23:22:13 GMT+8, Jeff LaCoursiere <jeff@...> wrote:



I wanted to comment on 1) below - we have that same concept in mind.? We are working on a BMS design that will basically allow cells to be "dropped out" of series, the output run through a boost circuit to maintain steady voltage.? There are of course limits to how many can drop out and we are very much at the experimental stage here, but there is some hope :)

Jeff LaCoursiere
s/v Angels Quest


On 4/29/21 10:06 AM, oreillygb@... wrote:
First Draft of Schematic. Using Lishen 202Ah. I decided to go with the BMS only actively controlling the charge side of the circuit and opted for passive monitoring on the load side. Using a victron 712 for monitoring and hopefully can connect it to a relay to shut off charge circuit at predetermined voltage. Guys please tell me what I have missed.

Couple of points.

1) Passive Load monitoring. I have decided to go this route as i understand that the load BMS can turn off for 2 reasons, obviously first is if whole bank drops to a lower than 20%SOC and secondly if single cells fail. From my perspective if I have a single cell failure I would rather still be able to use the other 15 cells than have no power. If I let my bank drop to below SOC of 20% that's?on me.
2) Want to keep house bank separate?for now, mainly as if I have to shut off my 48v bank for low SOC I don't want to have to worry about all my electronics being offline.
3) I want a separate?relay to shut off charge current so that I can set this manually. When I come back from a sail i want to be able to top bank up to about a 70% SOC for storage. Then on the day I want to sail I can top it off o 90%


-- 
Jeff LaCoursiere
StratusTalk, Inc.
703 496 4990 x108
815 546 6599 cell

--
Jeff LaCoursiere
s/v Angels Quest
St Thomas USVI

--

Jeff LaCoursiere
STRATUSTALK, INC. / CTO

Phone: +1 703.496.4990 x108
Mobile: +1 815.546.6599
Email: jeff@...
Website:
Address: One Freedom Square
13th Floor
Reston, VA 20190
? ? ?



--
Jeff LaCoursiere
s/v Angels Quest
St Thomas USVI


--

Jeff LaCoursiere
STRATUSTALK, INC. / CTO

Phone: +1 703.496.4990 x108
Mobile: +1 815.546.6599
Email: jeff@...
Website:
Address: One Freedom Square
13th Floor
Reston, VA 20190
? ? ?



--
Jeff LaCoursiere
s/v Angels Quest
St Thomas USVI


Re: Draft Schematic-Please give input

 

开云体育

The other thing about 48v vs 96v is really why not just run at 96v the whole time. Basically if you are making it possible then all the rest of the system has to be specd to 96v and I don’t see the reason to not keep it that way??

On Apr 30, 2021, at 11:12, Ryan Sweet via groups.io <ryan@...> wrote:

?

On Apr 30, 2021, at 9:38 AM, Carsten via <Carstensemail@...> wrote:

Another thing, how about making the motor wattage output adjustable, so it is possible to use eg. 96V for a burst mode ? Many 48V motors can be powered by 96V (or higher).
I assume that the wiring can handle that. Making two sets of banks 48V, to be serial connected to 96V.
The short "event" should of course be managed by the BMS/power management system.


This is interesting and something Ive wondered about but from what I’ve been able to discern it requires dynamically reprogramming the motor controller. ?You could imagine a switching setup that let you have 48v traction banks in parallel but then to change them to series. ?I wasn’t able to figure out a way to use the Seven Gen4 to do this kind of thing, at least from reading the manual. ?I fear I am about to venture into the world of the DVT software though and maybe its capable of that. I suppose if a person spent enough on controllers and cables you could have a dual system with two controllers and switch between them but I think you approach the point of diminishing returns.?

However, it points to a possible opportunity or maybe just a future feature that advanced motor controllers will enable. ?With EV regen becoming more popular in controllers, I would not be surprised if some battery management features also start to migrate to controllers as well.?

To be true, things made in China is not my cup of tea, but in these days, unfortunately simply unavoidable !
I was a supervisor in China for several years, and know how they make things, and all of QC is not like in the West.
Buy a ME1616 electromotor. Made in China, then sold in the West.
Buy yourself a german or US car. Half of the smaller parts in it are made in China by now.

Company supervisors are not in China now, because of the Made in China virus.
Who wants to spend 2-4 weeks in quarantine to go for an inspection ??
Who's checking the quality now ?

As I spin up my own commercial efforts I have been working with colleagues in CN to understand the quality dynamics and the manufacturing landscape and while I think some of these comments are in a general sense applicable, I think that the demands of growing sophistication in their domestic market, growing domestic regulatory regime, and a drive to differentiate by rising to the QC and supply chain standards of Korea, Japan, US, and Europe is pressuring a lot of CN companies to advance. ?I think now it is more a story of doing homework to understand your partners and their processes.

Now, the current chaos of the global shipping / logistics is another story! The Suez Canal incident has cost me several weeks and the knock-on effects will continue for months.?

However, I believe that new, checked, LiFePO4 batteries will last my sailing life out, but the electronics is another concern.
Especially in a marine environment (humid and salty).
Can you provide recommendations where to setup these (rather large) electronic regulators/inverters/BMS'es in the boat ?
I guess IP rating is not relevant, if not encapsuled in IP-rated boxes.
If put into boxes, then there's a cooling issue...

As far from any wet bilge or dripping shaft or outdoor moisture as possible. ?In the cabin if you can. If exposed to moist air frequently try running some electric air warmer/dryers or a dehumidifier (when on shore power).?


Working hard on the ultimate solution for my own EMS/Y system conversion design.

Cheers, guys
Carsten


Hint : EMS/Y = Electric Motor Sailing Yacht ;-)



On Friday, 30 April 2021, 02:46:25 GMT+8, Jeff LaCoursiere <jeff@...> wrote:


We haven't had any bad cells imported yet, knock wood.? We *are* doing our best to burn down our offices with our BMS experiments though :)? Also, our latest batch was all EVE 280AH cells, the Lishen 272AH are apparently "all gone".

Another cool idea we are kicking around... we want our 48v pack to have a 12v tap, so you can use it as your house battery as well as your traction battery.? I'm disappointed in the available downconverters, mostly current limited to 30-60A.? Maybe that would be enough for your house, but it wouldn't do it for mine.

So we want to try to cycle through internal banks of four cells, very quickly (like 10khz), connecting them in turn to the 12v tap.? We believe that this way you will be able to pull the full 1C discharge of the 16 cell pack (280A), but at 12v!? We hope to maintain balance in discharge by cycling very fast, but the BMS should pick up the slack.

Cheers,

Jeff LaCoursiere
s/v Angels Quest


On 4/29/21 11:34 AM, Carsten via wrote:
Hi, Jeff

Did you experience single/multiple cell dropouts from Lishen batteries so far ?

On Thursday, 29 April 2021, 23:22:13 GMT+8, Jeff LaCoursiere <jeff@...> wrote:



I wanted to comment on 1) below - we have that same concept in mind.? We are working on a BMS design that will basically allow cells to be "dropped out" of series, the output run through a boost circuit to maintain steady voltage.? There are of course limits to how many can drop out and we are very much at the experimental stage here, but there is some hope :)

Jeff LaCoursiere
s/v Angels Quest


On 4/29/21 10:06 AM, oreillygb@... wrote:
First Draft of Schematic. Using Lishen 202Ah. I decided to go with the BMS only actively controlling the charge side of the circuit and opted for passive monitoring on the load side. Using a victron 712 for monitoring and hopefully can connect it to a relay to shut off charge circuit at predetermined voltage. Guys please tell me what I have missed.

Couple of points.

1) Passive Load monitoring. I have decided to go this route as i understand that the load BMS can turn off for 2 reasons, obviously first is if whole bank drops to a lower than 20%SOC and secondly if single cells fail. From my perspective if I have a single cell failure I would rather still be able to use the other 15 cells than have no power. If I let my bank drop to below SOC of 20% that's?on me.
2) Want to keep house bank separate?for now, mainly as if I have to shut off my 48v bank for low SOC I don't want to have to worry about all my electronics being offline.
3) I want a separate?relay to shut off charge current so that I can set this manually. When I come back from a sail i want to be able to top bank up to about a 70% SOC for storage. Then on the day I want to sail I can top it off o 90%


-- 
Jeff LaCoursiere
StratusTalk, Inc.
703 496 4990 x108
815 546 6599 cell

--
Jeff LaCoursiere
s/v Angels Quest
St Thomas USVI

--

Jeff LaCoursiere
STRATUSTALK, INC. / CTO

Phone:+1 703.496.4990 x108
Mobile:+1 815.546.6599
Email:jeff@...
Website:
Address:One Freedom Square
13th Floor
Reston, VA 20190
? ? ?



--
Jeff LaCoursiere
s/v Angels Quest
St Thomas USVI


Re: Draft Schematic-Please give input

 

开云体育



On Apr 30, 2021, at 9:38 AM, Carsten via <Carstensemail@...> wrote:

Another thing, how about making the motor wattage output adjustable, so it is possible to use eg. 96V for a burst mode ? Many 48V motors can be powered by 96V (or higher).
I assume that the wiring can handle that. Making two sets of banks 48V, to be serial connected to 96V.
The short "event" should of course be managed by the BMS/power management system.


This is interesting and something Ive wondered about but from what I’ve been able to discern it requires dynamically reprogramming the motor controller. ?You could imagine a switching setup that let you have 48v traction banks in parallel but then to change them to series. ?I wasn’t able to figure out a way to use the Seven Gen4 to do this kind of thing, at least from reading the manual. ?I fear I am about to venture into the world of the DVT software though and maybe its capable of that. I suppose if a person spent enough on controllers and cables you could have a dual system with two controllers and switch between them but I think you approach the point of diminishing returns.?

However, it points to a possible opportunity or maybe just a future feature that advanced motor controllers will enable. ?With EV regen becoming more popular in controllers, I would not be surprised if some battery management features also start to migrate to controllers as well.?

To be true, things made in China is not my cup of tea, but in these days, unfortunately simply unavoidable !
I was a supervisor in China for several years, and know how they make things, and all of QC is not like in the West.
Buy a ME1616 electromotor. Made in China, then sold in the West.
Buy yourself a german or US car. Half of the smaller parts in it are made in China by now.

Company supervisors are not in China now, because of the Made in China virus.
Who wants to spend 2-4 weeks in quarantine to go for an inspection ??
Who's checking the quality now ?

As I spin up my own commercial efforts I have been working with colleagues in CN to understand the quality dynamics and the manufacturing landscape and while I think some of these comments are in a general sense applicable, I think that the demands of growing sophistication in their domestic market, growing domestic regulatory regime, and a drive to differentiate by rising to the QC and supply chain standards of Korea, Japan, US, and Europe is pressuring a lot of CN companies to advance. ?I think now it is more a story of doing homework to understand your partners and their processes.

Now, the current chaos of the global shipping / logistics is another story! The Suez Canal incident has cost me several weeks and the knock-on effects will continue for months.?

However, I believe that new, checked, LiFePO4 batteries will last my sailing life out, but the electronics is another concern.
Especially in a marine environment (humid and salty).
Can you provide recommendations where to setup these (rather large) electronic regulators/inverters/BMS'es in the boat ?
I guess IP rating is not relevant, if not encapsuled in IP-rated boxes.
If put into boxes, then there's a cooling issue...

As far from any wet bilge or dripping shaft or outdoor moisture as possible. ?In the cabin if you can. If exposed to moist air frequently try running some electric air warmer/dryers or a dehumidifier (when on shore power).?


Working hard on the ultimate solution for my own EMS/Y system conversion design.

Cheers, guys
Carsten


Hint : EMS/Y = Electric Motor Sailing Yacht ;-)



On Friday, 30 April 2021, 02:46:25 GMT+8, Jeff LaCoursiere <jeff@...> wrote:


We haven't had any bad cells imported yet, knock wood.? We *are* doing our best to burn down our offices with our BMS experiments though :)? Also, our latest batch was all EVE 280AH cells, the Lishen 272AH are apparently "all gone".

Another cool idea we are kicking around... we want our 48v pack to have a 12v tap, so you can use it as your house battery as well as your traction battery.? I'm disappointed in the available downconverters, mostly current limited to 30-60A.? Maybe that would be enough for your house, but it wouldn't do it for mine.

So we want to try to cycle through internal banks of four cells, very quickly (like 10khz), connecting them in turn to the 12v tap.? We believe that this way you will be able to pull the full 1C discharge of the 16 cell pack (280A), but at 12v!? We hope to maintain balance in discharge by cycling very fast, but the BMS should pick up the slack.

Cheers,

Jeff LaCoursiere
s/v Angels Quest


On 4/29/21 11:34 AM, Carsten via wrote:
Hi, Jeff

Did you experience single/multiple cell dropouts from Lishen batteries so far ?

On Thursday, 29 April 2021, 23:22:13 GMT+8, Jeff LaCoursiere <jeff@...> wrote:



I wanted to comment on 1) below - we have that same concept in mind.? We are working on a BMS design that will basically allow cells to be "dropped out" of series, the output run through a boost circuit to maintain steady voltage.? There are of course limits to how many can drop out and we are very much at the experimental stage here, but there is some hope :)

Jeff LaCoursiere
s/v Angels Quest


On 4/29/21 10:06 AM, oreillygb@... wrote:
First Draft of Schematic. Using Lishen 202Ah. I decided to go with the BMS only actively controlling the charge side of the circuit and opted for passive monitoring on the load side. Using a victron 712 for monitoring and hopefully can connect it to a relay to shut off charge circuit at predetermined voltage. Guys please tell me what I have missed.

Couple of points.

1) Passive Load monitoring. I have decided to go this route as i understand that the load BMS can turn off for 2 reasons, obviously first is if whole bank drops to a lower than 20%SOC and secondly if single cells fail. From my perspective if I have a single cell failure I would rather still be able to use the other 15 cells than have no power. If I let my bank drop to below SOC of 20% that's?on me.
2) Want to keep house bank separate?for now, mainly as if I have to shut off my 48v bank for low SOC I don't want to have to worry about all my electronics being offline.
3) I want a separate?relay to shut off charge current so that I can set this manually. When I come back from a sail i want to be able to top bank up to about a 70% SOC for storage. Then on the day I want to sail I can top it off o 90%


-- 
Jeff LaCoursiere
StratusTalk, Inc.
703 496 4990 x108
815 546 6599 cell

--
Jeff LaCoursiere
s/v Angels Quest
St Thomas USVI

--

Jeff LaCoursiere
STRATUSTALK, INC. / CTO

Phone:+1 703.496.4990 x108
Mobile:+1 815.546.6599
Email:jeff@...
Website:
Address:One Freedom Square
13th Floor
Reston, VA 20190
? ? ?



--
Jeff LaCoursiere
s/v Angels Quest
St Thomas USVI


Re: Draft Schematic-Please give input

 

开云体育

This sounds really useful. ?

And I wonder - At the “whole boat scale” - since its likely all going to be stationary, couldn’t you just provide a couple of circuits with downconverters or do you have individual loads that are > 60a? ?This is what I’ve done recently when deciding to setup another boat with a single large 48v bank.?

I also considered 80a downconverters, but decided I didn’t need them. ?One place for those is here:??

I did wonder but haven’t tried to figure out if you could run the DCDC converters in parallel, do you know?


On Apr 29, 2021, at 11:46 AM, Jeff LaCoursiere <jeff@...> wrote:

We haven't had any bad cells imported yet, knock wood.? We *are* doing our best to burn down our offices with our BMS experiments though :)? Also, our latest batch was all EVE 280AH cells, the Lishen 272AH are apparently "all gone".

Another cool idea we are kicking around... we want our 48v pack to have a 12v tap, so you can use it as your house battery as well as your traction battery.? I'm disappointed in the available downconverters, mostly current limited to 30-60A.? Maybe that would be enough for your house, but it wouldn't do it for mine.

So we want to try to cycle through internal banks of four cells, very quickly (like 10khz), connecting them in turn to the 12v tap.? We believe that this way you will be able to pull the full 1C discharge of the 16 cell pack (280A), but at 12v!? We hope to maintain balance in discharge by cycling very fast, but the BMS should pick up the slack.

Cheers,

Jeff LaCoursiere
s/v Angels Quest


On 4/29/21 11:34 AM, Carsten via wrote:
Hi, Jeff

Did you experience single/multiple cell dropouts from Lishen batteries so far ?


On Thursday, 29 April 2021, 23:22:13 GMT+8, Jeff LaCoursiere <jeff@...> wrote:



I wanted to comment on 1) below - we have that same concept in mind.? We are working on a BMS design that will basically allow cells to be "dropped out" of series, the output run through a boost circuit to maintain steady voltage.? There are of course limits to how many can drop out and we are very much at the experimental stage here, but there is some hope :)

Jeff LaCoursiere
s/v Angels Quest


On 4/29/21 10:06 AM, oreillygb@... wrote:
First Draft of Schematic. Using Lishen 202Ah. I decided to go with the BMS only actively controlling the charge side of the circuit and opted for passive monitoring on the load side. Using a victron 712 for monitoring and hopefully can connect it to a relay to shut off charge circuit at predetermined voltage. Guys please tell me what I have missed.

Couple of points.

1) Passive Load monitoring. I have decided to go this route as i understand that the load BMS can turn off for 2 reasons, obviously first is if whole bank drops to a lower than 20%SOC and secondly if single cells fail. From my perspective if I have a single cell failure I would rather still be able to use the other 15 cells than have no power. If I let my bank drop to below SOC of 20% that's?on me.
2) Want to keep house bank separate?for now, mainly as if I have to shut off my 48v bank for low SOC I don't want to have to worry about all my electronics being offline.
3) I want a separate?relay to shut off charge current so that I can set this manually. When I come back from a sail i want to be able to top bank up to about a 70% SOC for storage. Then on the day I want to sail I can top it off o 90%


-- 
Jeff LaCoursiere
StratusTalk, Inc.
703 496 4990 x108
815 546 6599 cell

--
Jeff LaCoursiere
s/v Angels Quest
St Thomas USVI

--

Jeff LaCoursiere
STRATUSTALK, INC. / CTO

Phone: +1 703.496.4990 x108
Mobile: +1 815.546.6599
Email: jeff@...
Website:
Address: One Freedom Square
13th Floor
Reston, VA 20190
? ? ?



--
Jeff LaCoursiere
s/v Angels Quest
St Thomas USVI


Re: Draft Schematic-Please give input

 

开云体育


Anyone considering going all electric propulsion in the salty ocean environment is being naive. The IC and computer components will corrode unless sealed circuit board tech, like in military, automotive ECUs and even in residential clothes dryers is used. That makes repair maintenance difficult....unless spare sealed circuit boards can be easily swapped? out.


On 30/04/2021 11:02 a.m., Jeff LaCoursiere wrote:


Oh man are you preaching to the choir here.? I get so frustrated - we are doing what I feel is cutting edge stuff, and it requires components and tools that you simply cannot buy anywhere else.? Perfect example that blew me away last week.? We have a lead on making drop-in replacements for 8D batteries.? We hadn't really planned to go this route, but why not?? So I start looking for empty 8D battery cases (note - not an 8D battery BOX, of which you can find many, that is what the 8D case will go into for "protection").
computer compenent
A bunch on ebay, but every single one is either from China or being distributed by someone who got it from China.

Do a web search - there simply aren't any US companies making these plastic boxes.? Why the heck not?? In the end I ordered some from appbattery.com, and will twiddle my thumbs for the next month until they get here.

Chargers, balancing circuits, cell protection circuits... ALL of this stuff, only from China.

It makes me think that we are way more dependent than most realize!

Great ideas below, by the way, we will noodle on them and make some comments :)

Jeff LaCoursiere
s/v Angels Quest


On 4/30/21 11:38 AM, Carsten via groups.io wrote:
Interesting, Jeff !
12V sucked from 48V, without an inverter ! Thumbs up !

In your intended setup of your battery banks, do you use 1 common BMS, or 1 on each (48V) battery ?
How about redundancy, if a common BMS fails ? (= no power at all.)

Another thing, how about making the motor wattage output adjustable, so it is possible to use eg. 96V for a burst mode ? Many 48V motors can be powered by 96V (or higher).
I assume that the wiring can handle that. Making two sets of banks 48V, to be serial connected to 96V.
The short "event" should of course be managed by the BMS/power management system.

i'm wondering if this new Li-battery technology is becoming a little too advanced for sailing now...
Safety first, when out on the water, right ? We can't just park the boat at the curb and call a cab when out on the blue.

To be true, things made in China is not my cup of tea, but in these days, unfortunately simply unavoidable !
I was a supervisor in China for several years, and know how they make things, and all of QC is not like in the West.
Buy a ME1616 electromotor. Made in China, then sold in the West.
Buy yourself a german or US car. Half of the smaller parts in it are made in China by now.

Company supervisors are not in China now, because of the Made in China virus.
Who wants to spend 2-4 weeks in quarantine to go for an inspection ??
Who's checking the quality now ?

However, I believe that new, checked, LiFePO4 batteries will last my sailing life out, but the electronics is another concern.
Especially in a marine environment (humid and salty).
Can you provide recommendations where to setup these (rather large) electronic regulators/inverters/BMS'es in the boat ?
I guess IP rating is not relevant, if not encapsuled in IP-rated boxes.
If put into boxes, then there's a cooling issue...

Working hard on the ultimate solution for my own EMS/Y system conversion design.

Cheers, guys
Carsten


Hint : EMS/Y = Electric Motor Sailing Yacht ;-)



On Friday, 30 April 2021, 02:46:25 GMT+8, Jeff LaCoursiere <jeff@...> wrote:


We haven't had any bad cells imported yet, knock wood.? We *are* doing our best to burn down our offices with our BMS experiments though :)? Also, our latest batch was all EVE 280AH cells, the Lishen 272AH are apparently "all gone".

Another cool idea we are kicking around... we want our 48v pack to have a 12v tap, so you can use it as your house battery as well as your traction battery.? I'm disappointed in the available downconverters, mostly current limited to 30-60A.? Maybe that would be enough for your house, but it wouldn't do it for mine.

So we want to try to cycle through internal banks of four cells, very quickly (like 10khz), connecting them in turn to the 12v tap.? We believe that this way you will be able to pull the full 1C discharge of the 16 cell pack (280A), but at 12v!? We hope to maintain balance in discharge by cycling very fast, but the BMS should pick up the slack.

Cheers,

Jeff LaCoursiere
s/v Angels Quest


On 4/29/21 11:34 AM, Carsten via groups.io wrote:
Hi, Jeff

Did you experience single/multiple cell dropouts from Lishen batteries so far ?

On Thursday, 29 April 2021, 23:22:13 GMT+8, Jeff LaCoursiere <jeff@...> wrote:



I wanted to comment on 1) below - we have that same concept in mind.? We are working on a BMS design that will basically allow cells to be "dropped out" of series, the output run through a boost circuit to maintain steady voltage.? There are of course limits to how many can drop out and we are very much at the experimental stage here, but there is some hope :)

Jeff LaCoursiere
s/v Angels Quest


On 4/29/21 10:06 AM, oreillygb@... wrote:
First Draft of Schematic. Using Lishen 202Ah. I decided to go with the BMS only actively controlling the charge side of the circuit and opted for passive monitoring on the load side. Using a victron 712 for monitoring and hopefully can connect it to a relay to shut off charge circuit at predetermined voltage. Guys please tell me what I have missed.

Couple of points.

1) Passive Load monitoring. I have decided to go this route as i understand that the load BMS can turn off for 2 reasons, obviously first is if whole bank drops to a lower than 20%SOC and secondly if single cells fail. From my perspective if I have a single cell failure I would rather still be able to use the other 15 cells than have no power. If I let my bank drop to below SOC of 20% that's?on me.
2) Want to keep house bank separate?for now, mainly as if I have to shut off my 48v bank for low SOC I don't want to have to worry about all my electronics being offline.
3) I want a separate?relay to shut off charge current so that I can set this manually. When I come back from a sail i want to be able to top bank up to about a 70% SOC for storage. Then on the day I want to sail I can top it off o 90%


-- 
Jeff LaCoursiere
StratusTalk, Inc.
703 496 4990 x108
815 546 6599 cell

--
Jeff LaCoursiere
s/v Angels Quest
St Thomas USVI

--

Jeff LaCoursiere
STRATUSTALK, INC. / CTO

Phone: +1 703.496.4990 x108
Mobile: +1 815.546.6599
Email: jeff@...
Website:
Address: One Freedom Square
13th Floor
Reston, VA 20190
? ? ?



--
Jeff LaCoursiere
s/v Angels Quest
St Thomas USVI


-- 
Jeff LaCoursiere
StratusTalk, Inc.
703 496 4990 x108
815 546 6599 cell

--
Jeff LaCoursiere
s/v Angels Quest
St Thomas USVI


Re: Draft Schematic-Please give input

 

开云体育


Oh man are you preaching to the choir here.? I get so frustrated - we are doing what I feel is cutting edge stuff, and it requires components and tools that you simply cannot buy anywhere else.? Perfect example that blew me away last week.? We have a lead on making drop-in replacements for 8D batteries.? We hadn't really planned to go this route, but why not?? So I start looking for empty 8D battery cases (note - not an 8D battery BOX, of which you can find many, that is what the 8D case will go into for "protection").

A bunch on ebay, but every single one is either from China or being distributed by someone who got it from China.

Do a web search - there simply aren't any US companies making these plastic boxes.? Why the heck not?? In the end I ordered some from appbattery.com, and will twiddle my thumbs for the next month until they get here.

Chargers, balancing circuits, cell protection circuits... ALL of this stuff, only from China.

It makes me think that we are way more dependent than most realize!

Great ideas below, by the way, we will noodle on them and make some comments :)

Jeff LaCoursiere
s/v Angels Quest


On 4/30/21 11:38 AM, Carsten via groups.io wrote:
Interesting, Jeff !
12V sucked from 48V, without an inverter ! Thumbs up !

In your intended setup of your battery banks, do you use 1 common BMS, or 1 on each (48V) battery ?
How about redundancy, if a common BMS fails ? (= no power at all.)

Another thing, how about making the motor wattage output adjustable, so it is possible to use eg. 96V for a burst mode ? Many 48V motors can be powered by 96V (or higher).
I assume that the wiring can handle that. Making two sets of banks 48V, to be serial connected to 96V.
The short "event" should of course be managed by the BMS/power management system.

i'm wondering if this new Li-battery technology is becoming a little too advanced for sailing now...
Safety first, when out on the water, right ? We can't just park the boat at the curb and call a cab when out on the blue.

To be true, things made in China is not my cup of tea, but in these days, unfortunately simply unavoidable !
I was a supervisor in China for several years, and know how they make things, and all of QC is not like in the West.
Buy a ME1616 electromotor. Made in China, then sold in the West.
Buy yourself a german or US car. Half of the smaller parts in it are made in China by now.

Company supervisors are not in China now, because of the Made in China virus.
Who wants to spend 2-4 weeks in quarantine to go for an inspection ??
Who's checking the quality now ?

However, I believe that new, checked, LiFePO4 batteries will last my sailing life out, but the electronics is another concern.
Especially in a marine environment (humid and salty).
Can you provide recommendations where to setup these (rather large) electronic regulators/inverters/BMS'es in the boat ?
I guess IP rating is not relevant, if not encapsuled in IP-rated boxes.
If put into boxes, then there's a cooling issue...

Working hard on the ultimate solution for my own EMS/Y system conversion design.

Cheers, guys
Carsten


Hint : EMS/Y = Electric Motor Sailing Yacht ;-)



On Friday, 30 April 2021, 02:46:25 GMT+8, Jeff LaCoursiere <jeff@...> wrote:


We haven't had any bad cells imported yet, knock wood.? We *are* doing our best to burn down our offices with our BMS experiments though :)? Also, our latest batch was all EVE 280AH cells, the Lishen 272AH are apparently "all gone".

Another cool idea we are kicking around... we want our 48v pack to have a 12v tap, so you can use it as your house battery as well as your traction battery.? I'm disappointed in the available downconverters, mostly current limited to 30-60A.? Maybe that would be enough for your house, but it wouldn't do it for mine.

So we want to try to cycle through internal banks of four cells, very quickly (like 10khz), connecting them in turn to the 12v tap.? We believe that this way you will be able to pull the full 1C discharge of the 16 cell pack (280A), but at 12v!? We hope to maintain balance in discharge by cycling very fast, but the BMS should pick up the slack.

Cheers,

Jeff LaCoursiere
s/v Angels Quest


On 4/29/21 11:34 AM, Carsten via groups.io wrote:
Hi, Jeff

Did you experience single/multiple cell dropouts from Lishen batteries so far ?

On Thursday, 29 April 2021, 23:22:13 GMT+8, Jeff LaCoursiere <jeff@...> wrote:



I wanted to comment on 1) below - we have that same concept in mind.? We are working on a BMS design that will basically allow cells to be "dropped out" of series, the output run through a boost circuit to maintain steady voltage.? There are of course limits to how many can drop out and we are very much at the experimental stage here, but there is some hope :)

Jeff LaCoursiere
s/v Angels Quest


On 4/29/21 10:06 AM, oreillygb@... wrote:
First Draft of Schematic. Using Lishen 202Ah. I decided to go with the BMS only actively controlling the charge side of the circuit and opted for passive monitoring on the load side. Using a victron 712 for monitoring and hopefully can connect it to a relay to shut off charge circuit at predetermined voltage. Guys please tell me what I have missed.

Couple of points.

1) Passive Load monitoring. I have decided to go this route as i understand that the load BMS can turn off for 2 reasons, obviously first is if whole bank drops to a lower than 20%SOC and secondly if single cells fail. From my perspective if I have a single cell failure I would rather still be able to use the other 15 cells than have no power. If I let my bank drop to below SOC of 20% that's?on me.
2) Want to keep house bank separate?for now, mainly as if I have to shut off my 48v bank for low SOC I don't want to have to worry about all my electronics being offline.
3) I want a separate?relay to shut off charge current so that I can set this manually. When I come back from a sail i want to be able to top bank up to about a 70% SOC for storage. Then on the day I want to sail I can top it off o 90%


-- 
Jeff LaCoursiere
StratusTalk, Inc.
703 496 4990 x108
815 546 6599 cell

--
Jeff LaCoursiere
s/v Angels Quest
St Thomas USVI

--

Jeff LaCoursiere
STRATUSTALK, INC. / CTO

Phone: +1 703.496.4990 x108
Mobile: +1 815.546.6599
Email: jeff@...
Website:
Address: One Freedom Square
13th Floor
Reston, VA 20190
? ? ?



--
Jeff LaCoursiere
s/v Angels Quest
St Thomas USVI


-- 
Jeff LaCoursiere
StratusTalk, Inc.
703 496 4990 x108
815 546 6599 cell

--
Jeff LaCoursiere
s/v Angels Quest
St Thomas USVI


Re: Draft Schematic-Please give input

 

Interesting, Jeff !
12V sucked from 48V, without an inverter ! Thumbs up !

In your intended setup of your battery banks, do you use 1 common BMS, or 1 on each (48V) battery ?
How about redundancy, if a common BMS fails ? (= no power at all.)

Another thing, how about making the motor wattage output adjustable, so it is possible to use eg. 96V for a burst mode ? Many 48V motors can be powered by 96V (or higher).
I assume that the wiring can handle that. Making two sets of banks 48V, to be serial connected to 96V.
The short "event" should of course be managed by the BMS/power management system.

i'm wondering if this new Li-battery technology is becoming a little too advanced for sailing now...
Safety first, when out on the water, right ? We can't just park the boat at the curb and call a cab when out on the blue.

To be true, things made in China is not my cup of tea, but in these days, unfortunately simply unavoidable !
I was a supervisor in China for several years, and know how they make things, and all of QC is not like in the West.
Buy a ME1616 electromotor. Made in China, then sold in the West.
Buy yourself a german or US car. Half of the smaller parts in it are made in China by now.

Company supervisors are not in China now, because of the Made in China virus.
Who wants to spend 2-4 weeks in quarantine to go for an inspection ??
Who's checking the quality now ?

However, I believe that new, checked, LiFePO4 batteries will last my sailing life out, but the electronics is another concern.
Especially in a marine environment (humid and salty).
Can you provide recommendations where to setup these (rather large) electronic regulators/inverters/BMS'es in the boat ?
I guess IP rating is not relevant, if not encapsuled in IP-rated boxes.
If put into boxes, then there's a cooling issue...

Working hard on the ultimate solution for my own EMS/Y system conversion design.

Cheers, guys
Carsten


Hint : EMS/Y = Electric Motor Sailing Yacht ;-)



On Friday, 30 April 2021, 02:46:25 GMT+8, Jeff LaCoursiere <jeff@...> wrote:


We haven't had any bad cells imported yet, knock wood.? We *are* doing our best to burn down our offices with our BMS experiments though :)? Also, our latest batch was all EVE 280AH cells, the Lishen 272AH are apparently "all gone".

Another cool idea we are kicking around... we want our 48v pack to have a 12v tap, so you can use it as your house battery as well as your traction battery.? I'm disappointed in the available downconverters, mostly current limited to 30-60A.? Maybe that would be enough for your house, but it wouldn't do it for mine.

So we want to try to cycle through internal banks of four cells, very quickly (like 10khz), connecting them in turn to the 12v tap.? We believe that this way you will be able to pull the full 1C discharge of the 16 cell pack (280A), but at 12v!? We hope to maintain balance in discharge by cycling very fast, but the BMS should pick up the slack.

Cheers,

Jeff LaCoursiere
s/v Angels Quest


On 4/29/21 11:34 AM, Carsten via groups.io wrote:
Hi, Jeff

Did you experience single/multiple cell dropouts from Lishen batteries so far ?

On Thursday, 29 April 2021, 23:22:13 GMT+8, Jeff LaCoursiere <jeff@...> wrote:



I wanted to comment on 1) below - we have that same concept in mind.? We are working on a BMS design that will basically allow cells to be "dropped out" of series, the output run through a boost circuit to maintain steady voltage.? There are of course limits to how many can drop out and we are very much at the experimental stage here, but there is some hope :)

Jeff LaCoursiere
s/v Angels Quest


On 4/29/21 10:06 AM, oreillygb@... wrote:
First Draft of Schematic. Using Lishen 202Ah. I decided to go with the BMS only actively controlling the charge side of the circuit and opted for passive monitoring on the load side. Using a victron 712 for monitoring and hopefully can connect it to a relay to shut off charge circuit at predetermined voltage. Guys please tell me what I have missed.

Couple of points.

1) Passive Load monitoring. I have decided to go this route as i understand that the load BMS can turn off for 2 reasons, obviously first is if whole bank drops to a lower than 20%SOC and secondly if single cells fail. From my perspective if I have a single cell failure I would rather still be able to use the other 15 cells than have no power. If I let my bank drop to below SOC of 20% that's?on me.
2) Want to keep house bank separate?for now, mainly as if I have to shut off my 48v bank for low SOC I don't want to have to worry about all my electronics being offline.
3) I want a separate?relay to shut off charge current so that I can set this manually. When I come back from a sail i want to be able to top bank up to about a 70% SOC for storage. Then on the day I want to sail I can top it off o 90%


-- 
Jeff LaCoursiere
StratusTalk, Inc.
703 496 4990 x108
815 546 6599 cell

--
Jeff LaCoursiere
s/v Angels Quest
St Thomas USVI

--

Jeff LaCoursiere
STRATUSTALK, INC. / CTO

Phone:+1 703.496.4990 x108
Mobile:+1 815.546.6599
Email:jeff@...
Website:
Address:One Freedom Square
13th Floor
Reston, VA 20190
? ? ?



--
Jeff LaCoursiere
s/v Angels Quest
St Thomas USVI


Re: Draft Schematic-Please give input

 

I am skeptical of passive load monitoring. Your reasons for choosing it are all about the pack. What about the load? What if your motor controller fails and wants to short the pack? With passive monitoring, there is no protection. There is also no guarantee that you will be attentive to a load issue when it occurs. You might have your hands full with other aspects of the situation.

I understand about not wanting to be stuck because of one bad cell. Maybe some sort of BMS bypass on the load side might be a reasonable compromise? If your BMS shuts down while using the pack, assess the situation, resolve it, or proceed carefully on bypass if needed.

I added a bypass on the charging side, since I use a solar charger, and never want to get stuck because the pack voltage was too low and the BMS wouldn't let the charger charge it.

Interesting that I destroyed two cells when I tried to do passive monitoring. Since installing the BMS between the charging and load circuits and the pack, I've had no problems. Maybe it's a karma thing?


Re: Draft Schematic-Please give input

 

开云体育

We haven't had any bad cells imported yet, knock wood.? We *are* doing our best to burn down our offices with our BMS experiments though :)? Also, our latest batch was all EVE 280AH cells, the Lishen 272AH are apparently "all gone".

Another cool idea we are kicking around... we want our 48v pack to have a 12v tap, so you can use it as your house battery as well as your traction battery.? I'm disappointed in the available downconverters, mostly current limited to 30-60A.? Maybe that would be enough for your house, but it wouldn't do it for mine.

So we want to try to cycle through internal banks of four cells, very quickly (like 10khz), connecting them in turn to the 12v tap.? We believe that this way you will be able to pull the full 1C discharge of the 16 cell pack (280A), but at 12v!? We hope to maintain balance in discharge by cycling very fast, but the BMS should pick up the slack.

Cheers,

Jeff LaCoursiere
s/v Angels Quest


On 4/29/21 11:34 AM, Carsten via groups.io wrote:
Hi, Jeff

Did you experience single/multiple cell dropouts from Lishen batteries so far ?


On Thursday, 29 April 2021, 23:22:13 GMT+8, Jeff LaCoursiere <jeff@...> wrote:



I wanted to comment on 1) below - we have that same concept in mind.? We are working on a BMS design that will basically allow cells to be "dropped out" of series, the output run through a boost circuit to maintain steady voltage.? There are of course limits to how many can drop out and we are very much at the experimental stage here, but there is some hope :)

Jeff LaCoursiere
s/v Angels Quest


On 4/29/21 10:06 AM, oreillygb@... wrote:
First Draft of Schematic. Using Lishen 202Ah. I decided to go with the BMS only actively controlling the charge side of the circuit and opted for passive monitoring on the load side. Using a victron 712 for monitoring and hopefully can connect it to a relay to shut off charge circuit at predetermined voltage. Guys please tell me what I have missed.

Couple of points.

1) Passive Load monitoring. I have decided to go this route as i understand that the load BMS can turn off for 2 reasons, obviously first is if whole bank drops to a lower than 20%SOC and secondly if single cells fail. From my perspective if I have a single cell failure I would rather still be able to use the other 15 cells than have no power. If I let my bank drop to below SOC of 20% that's?on me.
2) Want to keep house bank separate?for now, mainly as if I have to shut off my 48v bank for low SOC I don't want to have to worry about all my electronics being offline.
3) I want a separate?relay to shut off charge current so that I can set this manually. When I come back from a sail i want to be able to top bank up to about a 70% SOC for storage. Then on the day I want to sail I can top it off o 90%


-- 
Jeff LaCoursiere
StratusTalk, Inc.
703 496 4990 x108
815 546 6599 cell

--
Jeff LaCoursiere
s/v Angels Quest
St Thomas USVI

--

Jeff LaCoursiere
STRATUSTALK, INC. / CTO

Phone: +1 703.496.4990 x108
Mobile: +1 815.546.6599
Email: jeff@...
Website:
Address: One Freedom Square
13th Floor
Reston, VA 20190
? ? ?



--
Jeff LaCoursiere
s/v Angels Quest
St Thomas USVI


Re: EV Gavia: Electrical suggestions

 

Hi Reuben, well wear with the range extender. People should be aware that these cheap generators come with a "running in" oil, intentionally low lubricity to allow the piston rings to wear a little and seal better. If you don't put a good oil in after 20 running hours then they wear out very quickly. You could get years out of it. Please ignore me if it's a 2-stroke.

Isn't it a neat idea, though. Looks like a brushless motor and a wind turbine charge controller coupled to an engine. Anybody with access to a lathe and mill could do it, maybe using high end components where affluence allows.?
Regards Anthony


On Wed 28 Apr 2021, 8:49 PM Reuben Trane via <rjtrane=[email protected]> wrote:
Carsten,

I purchased my range extender from Tom’s Machinery:?

I purchased the 6kW/48Vdc unit - I should have bought the 4kW one since these are amp limited - at 48v I’d get the same amps from a 4kW unit as the 6kW and it comes in a neater package with the controller and rectifier built into the casing. I did get a remote gas tank rather than integral. Response from vendor was as good as could be expected. They immediately replaced several items damaged in shipping. And eventually the controller which mal-functioned.?

Right now the throttle is not automatic - I just set it on high. I have yet to run it for an extended period of time. I don’t use the automatic on/off features.?

It’s installed in a FRP box with the exhaust ported outside along with an exhaust blower that changes the air every couple of minutes. I just bought a temp gauge to see what the ambient temperature is.?

Any other questions?

Reuben



On Apr 27, 2021, at 11:09 AM, Carsten via <Carstensemail=[email protected]> wrote:

?
Hi, Reuben

Could you please tell me more of your experiments with the CN gen in point 3. please ?

I have a link, and it makes me just more confused than enlightened... I even had a few laughs when reading it :-)
My guess - not certified in ANY heavy regulated country.

Looking forward to hear from you,
Carsten


On Tuesday, 27 April 2021, 20:40:09 GMT+8, Reuben Trane via <rjtrane=[email protected]> wrote:


Great project and presentation. I have a 48v system on my solar powered 12m cat “Sunshine” that has been off the grid over 5 years. Here’s my thoughts:

1. I feel you’d be better off building your LFP pack using prismatic cells from Winston, CALB or Sinopoly. Use cells of the AH size you want to minimize connections - 16 cells total. If you’re set on “drop-in” LFP batteries, I’d consider Victron (they do make them?). Since you’re using Victron components, then stick with them for a BMS that can communicate with your inverter/charger and solar controllers.

2. If your 12v battery is near the windlass, I’d suggest the DC/DC charger also be located near this battery. You can then run sizable wires to your 12v panel.

3. I have been experimenting with a Range Extender (48vdc generator) from AliExpress. It has a small air-cooled gas motor started by the 3-phase AC generator. It has a controller and a bridge rectifier with DC charging output. These range controllers are designed for EVs and output about 4kW/80A for a 48v system.

4. Solbian makes the best flex panels using SunPower cells. I have rigid SunPower panels installed in 2008 and still working fine.

5. I have considered wind but not added any - small units barely produce much of anything - my research indicates using ones with blade diameters if 6’ or more to get anything really useful.

Where are you doing this project? I’m in Key Largo, Florida - a perfect spot for a solar boat. Any plans to share?

Good going.

Reuben Trane






Re: Draft Schematic-Please give input

 

开云体育

I like your diagram.? I have a couple questions.???

You show the shunt for the monitor between the BMS and the neg lead.? That makes sense but it can't be done that way on a battery like a Battleborn with its internal BMS.? So I wonder which way is better?? Should the BMS be considered a part of the battery??? So the battery is in effect a box with all the BMS components inside.?

You show a separate negative lead to the BMS from the charger?? Does your BMS have a seperate neg input fro the charger?

What BMS are you planning this with?

Thanks, Dan Pfeiffer

?

On 2021-04-29 10:06 am, oreillygb@... wrote:

First Draft of Schematic. Using Lishen 202Ah. I decided to go with the BMS only actively controlling the charge side of the circuit and opted for passive monitoring on the load side. Using a victron 712 for monitoring and hopefully can connect it to a relay to shut off charge circuit at predetermined voltage. Guys please tell me what I have missed.

Couple of points.

1) Passive Load monitoring. I have decided to go this route as i understand that the load BMS can turn off for 2 reasons, obviously first is if whole bank drops to a lower than 20%SOC and secondly if single cells fail. From my perspective if I have a single cell failure I would rather still be able to use the other 15 cells than have no power. If I let my bank drop to below SOC of 20% that's?on me.
2) Want to keep house bank separate?for now, mainly as if I have to shut off my 48v bank for low SOC I don't want to have to worry about all my electronics being offline.
3) I want a separate?relay to shut off charge current so that I can set this manually. When I come back from a sail i want to be able to top bank up to about a 70% SOC for storage. Then on the day I want to sail I can top it off o 90%


Re: Draft Schematic-Please give input

 

Hi, Jeff

Did you experience single/multiple cell dropouts from Lishen batteries so far ?


On Thursday, 29 April 2021, 23:22:13 GMT+8, Jeff LaCoursiere <jeff@...> wrote:



I wanted to comment on 1) below - we have that same concept in mind.? We are working on a BMS design that will basically allow cells to be "dropped out" of series, the output run through a boost circuit to maintain steady voltage.? There are of course limits to how many can drop out and we are very much at the experimental stage here, but there is some hope :)

Jeff LaCoursiere
s/v Angels Quest


On 4/29/21 10:06 AM, oreillygb@... wrote:
First Draft of Schematic. Using Lishen 202Ah. I decided to go with the BMS only actively controlling the charge side of the circuit and opted for passive monitoring on the load side. Using a victron 712 for monitoring and hopefully can connect it to a relay to shut off charge circuit at predetermined voltage. Guys please tell me what I have missed.

Couple of points.

1) Passive Load monitoring. I have decided to go this route as i understand that the load BMS can turn off for 2 reasons, obviously first is if whole bank drops to a lower than 20%SOC and secondly if single cells fail. From my perspective if I have a single cell failure I would rather still be able to use the other 15 cells than have no power. If I let my bank drop to below SOC of 20% that's?on me.
2) Want to keep house bank separate?for now, mainly as if I have to shut off my 48v bank for low SOC I don't want to have to worry about all my electronics being offline.
3) I want a separate?relay to shut off charge current so that I can set this manually. When I come back from a sail i want to be able to top bank up to about a 70% SOC for storage. Then on the day I want to sail I can top it off o 90%


-- 
Jeff LaCoursiere
StratusTalk, Inc.
703 496 4990 x108
815 546 6599 cell

--
Jeff LaCoursiere
s/v Angels Quest
St Thomas USVI


Re: Draft Schematic-Please give input

 

开云体育


I wanted to comment on 1) below - we have that same concept in mind.? We are working on a BMS design that will basically allow cells to be "dropped out" of series, the output run through a boost circuit to maintain steady voltage.? There are of course limits to how many can drop out and we are very much at the experimental stage here, but there is some hope :)

Jeff LaCoursiere
s/v Angels Quest


On 4/29/21 10:06 AM, oreillygb@... wrote:
First Draft of Schematic. Using Lishen 202Ah. I decided to go with the BMS only actively controlling the charge side of the circuit and opted for passive monitoring on the load side. Using a victron 712 for monitoring and hopefully can connect it to a relay to shut off charge circuit at predetermined voltage. Guys please tell me what I have missed.

Couple of points.

1) Passive Load monitoring. I have decided to go this route as i understand that the load BMS can turn off for 2 reasons, obviously first is if whole bank drops to a lower than 20%SOC and secondly if single cells fail. From my perspective if I have a single cell failure I would rather still be able to use the other 15 cells than have no power. If I let my bank drop to below SOC of 20% that's?on me.
2) Want to keep house bank separate?for now, mainly as if I have to shut off my 48v bank for low SOC I don't want to have to worry about all my electronics being offline.
3) I want a separate?relay to shut off charge current so that I can set this manually. When I come back from a sail i want to be able to top bank up to about a 70% SOC for storage. Then on the day I want to sail I can top it off o 90%


-- 
Jeff LaCoursiere
StratusTalk, Inc.
703 496 4990 x108
815 546 6599 cell

--
Jeff LaCoursiere
s/v Angels Quest
St Thomas USVI


Re: Draft Schematic-Please give input

 

开云体育

I actually bought 20 plus busbars so that I could keep a few spare. I paid $1437 for all 20 from Xuba on Alibaba, they all arrived yesterday. As easy as ordering on Amazon except for the wait.?


From: [email protected] <[email protected]> on behalf of Bob Jennings <heatnh@...>
Sent: Thursday, April 29, 2021 8:13 AM
To: [email protected] <[email protected]>
Subject: Re: [electricboats] Draft Schematic-Please give input
?
Not trying to be nosey but what will t cost for your Lishen bank? Someone else I know has bought from them & they're very pleased with it.

On Thu, Apr 29, 2021, 11:08 AM <oreillygb@...> wrote:
First Draft of Schematic. Using Lishen 202Ah. I decided to go with the BMS only actively controlling the charge side of the circuit and opted for passive monitoring on the load side. Using a victron 712 for monitoring and hopefully can connect it to a relay to shut off charge circuit at predetermined voltage. Guys please tell me what I have missed.

Couple of points.

1) Passive Load monitoring. I have decided to go this route as i understand that the load BMS can turn off for 2 reasons, obviously first is if whole bank drops to a lower than 20%SOC and secondly if single cells fail. From my perspective if I have a single cell failure I would rather still be able to use the other 15 cells than have no power. If I let my bank drop to below SOC of 20% that's?on me.
2) Want to keep house bank separate?for now, mainly as if I have to shut off my 48v bank for low SOC I don't want to have to worry about all my electronics being offline.
3) I want a separate?relay to shut off charge current so that I can set this manually. When I come back from a sail i want to be able to top bank up to about a 70% SOC for storage. Then on the day I want to sail I can top it off o 90%


Re: Draft Schematic-Please give input

Bob Jennings
 

Not trying to be nosey but what will t cost for your Lishen bank? Someone else I know has bought from them & they're very pleased with it.


On Thu, Apr 29, 2021, 11:08 AM <oreillygb@...> wrote:
First Draft of Schematic. Using Lishen 202Ah. I decided to go with the BMS only actively controlling the charge side of the circuit and opted for passive monitoring on the load side. Using a victron 712 for monitoring and hopefully can connect it to a relay to shut off charge circuit at predetermined voltage. Guys please tell me what I have missed.

Couple of points.

1) Passive Load monitoring. I have decided to go this route as i understand that the load BMS can turn off for 2 reasons, obviously first is if whole bank drops to a lower than 20%SOC and secondly if single cells fail. From my perspective if I have a single cell failure I would rather still be able to use the other 15 cells than have no power. If I let my bank drop to below SOC of 20% that's?on me.
2) Want to keep house bank separate?for now, mainly as if I have to shut off my 48v bank for low SOC I don't want to have to worry about all my electronics being offline.
3) I want a separate?relay to shut off charge current so that I can set this manually. When I come back from a sail i want to be able to top bank up to about a 70% SOC for storage. Then on the day I want to sail I can top it off o 90%


Draft Schematic-Please give input

 

First Draft of Schematic. Using Lishen 202Ah. I decided to go with the BMS only actively controlling the charge side of the circuit and opted for passive monitoring on the load side. Using a victron 712 for monitoring and hopefully can connect it to a relay to shut off charge circuit at predetermined voltage. Guys please tell me what I have missed.

Couple of points.

1) Passive Load monitoring. I have decided to go this route as i understand that the load BMS can turn off for 2 reasons, obviously first is if whole bank drops to a lower than 20%SOC and secondly if single cells fail. From my perspective if I have a single cell failure I would rather still be able to use the other 15 cells than have no power. If I let my bank drop to below SOC of 20% that's?on me.
2) Want to keep house bank separate?for now, mainly as if I have to shut off my 48v bank for low SOC I don't want to have to worry about all my electronics being offline.
3) I want a separate?relay to shut off charge current so that I can set this manually. When I come back from a sail i want to be able to top bank up to about a 70% SOC for storage. Then on the day I want to sail I can top it off o 90%