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i am a marine service company in mexico wishing help in converting a 40 foot trimaran from diesel to electric propulsion.? ?Garth Jones.? ?I need some help and advice??
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I got my motor and controller from Thunderstruck-ev.com. ?I just added the batteries and in my case generators for my idea of how I wanted to use the system. ?They have been extremely helpful along the way. ?There are other outfits out there that I cannot speak for. ?Only that these guys have been great for me. ?My trimaran is 38¡¯ x 22¡¯6¡±, 9k lbs. ?I chose the air cooled motor because I like the idea a bag won¡¯t get sucked up into my cooling line and overheat the motor. ?That being said I have yet to test mine in the Florida heat. ?I¡¯ll know more this summer how hard it is to keep cool. ?Ultimately I may have to switch. ?But I¡¯d rather try the option that would be simplest first.
There are more and more of us out here to give help as time goes. ?This is really the future of sailboat auxiliary I think. ?I¡¯m hopeful power boats are able to use it as well. ?As it stands I have a 2 to 1 reduction and I¡¯m going to be trying my 2 blade prop previously used for a 30hp Yanmar. ?It was pushing a lot of water at 40amps today for an hour at the dock. ?I¡¯m still working on finishing up and organizing wires etc. but hopefully in the next few weeks I¡¯ll take her for a run out to the gulf to see if 40amps is 5knots or what. ?That¡¯s my hope. ?With two of my 350w solar panels connected it was putting roughly 10amps into the system so the batteries were only putting out 30amps. ? This was good to see even though today was best case for solar. ?No clouds at all.?
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On Feb 8, 2020, at 4:11 PM, gimmx via Groups.Io <gimmx@...> wrote:
?i am a marine service company in mexico wishing help in converting a 40 foot trimaran from diesel to electric propulsion.? ?Garth Jones.? ?I need some help and advice??
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I have the same set up. 10 kw ? 48 v system. Lithium iron phosphate cells in parallel??and seriesRunning tethered to the dock. 4 hrs. With lithium dyi??assembly ?70a continuous running. No heat issues?Next week is the real test. I will keep you posted??Should be able to run hull speed 6 hrs or more. Cheers? Best regards, Larry Schmitz
On Saturday, February 8, 2020, 7:20 PM, Larry Brown <elcapitanbrown@...> wrote: I got my motor and controller from Thunderstruck-ev.com. ?I just added the batteries and in my case generators for my idea of how I wanted to use the system. ?They have been extremely helpful along the way. ?There are other outfits out there that I cannot speak for. ?Only that these guys have been great for me. ?My trimaran is 38¡¯ x 22¡¯6¡±, 9k lbs. ?I chose the air cooled motor because I like the idea a bag won¡¯t get sucked up into my cooling line and overheat the motor. ?That being said I have yet to test mine in the Florida heat. ?I¡¯ll know more this summer how hard it is to keep cool. ?Ultimately I may have to switch. ?But I¡¯d rather try the option that would be simplest first.
There are more and more of us out here to give help as time goes. ?This is really the future of sailboat auxiliary I think. ?I¡¯m hopeful power boats are able to use it as well. ?As it stands I have a 2 to 1 reduction and I¡¯m going to be trying my 2 blade prop previously used for a 30hp Yanmar. ?It was pushing a lot of water at 40amps today for an hour at the dock. ?I¡¯m still working on finishing up and organizing wires etc. but hopefully in the next few weeks I¡¯ll take her for a run out to the gulf to see if 40amps is 5knots or what. ?That¡¯s my hope. ?With two of my 350w solar panels connected it was putting roughly 10amps into the system so the batteries were only putting out 30amps. ? This was good to see even though today was best case for solar. ?No clouds at all.?
Hope this was helpful. On Feb 8, 2020, at 4:11 PM, gimmx via Groups.Io <gimmx@...> wrote:
?i am a marine service company in mexico wishing help in converting a 40 foot trimaran from diesel to electric propulsion.? ?Garth Jones.? ?I need some help and advice??
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Larry, what size and displacement is your vessel? ?Also, where are you (Keeping temp down in Tampa Bay would be more challenging than Victoria CA) and what are you using for ventilation?? ?I would love to have LiFePo batteries but the price doesn¡¯t seem to come down. ?Looking forward to aluminum batteries. ?The scuttlebut being that they will be better performing and with the lower materials cost they will be much cheaper. ?With plans on keeping my AGMs as long as I can I¡¯m only bringing them to 80% if possible. ?50 on occasion. ?Being able to use 90% of lithium every time with so many cycles is the cat¡¯s meow. ?
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On Feb 9, 2020, at 1:34 AM, L Schmitz via Groups.Io <terminalift@...> wrote:
?
I have the same set up. 10 kw ? 48 v system. Lithium iron phosphate cells in parallel??and seriesRunning tethered to the dock. 4 hrs. With lithium dyi??assembly ?70a continuous running. No heat issues?Next week is the real test. I will keep you posted??Should be able to run hull speed 6 hrs or more. Cheers? Best regards, Larry Schmitz
On Saturday, February 8, 2020, 7:20 PM, Larry Brown <elcapitanbrown@...> wrote: I got my motor and controller from Thunderstruck-ev.com. ?I just added the batteries and in my case generators for my idea of how I wanted to use the system. ?They have been extremely helpful along the way. ?There are other outfits out there that I cannot speak for. ?Only that these guys have been great for me. ?My trimaran is 38¡¯ x 22¡¯6¡±, 9k lbs. ?I chose the air cooled motor because I like the idea a bag won¡¯t get sucked up into my cooling line and overheat the motor. ?That being said I have yet to test mine in the Florida heat. ?I¡¯ll know more this summer how hard it is to keep cool. ?Ultimately I may have to switch. ?But I¡¯d rather try the option that would be simplest first.
There are more and more of us out here to give help as time goes. ?This is really the future of sailboat auxiliary I think. ?I¡¯m hopeful power boats are able to use it as well. ?As it stands I have a 2 to 1 reduction and I¡¯m going to be trying my 2 blade prop previously used for a 30hp Yanmar. ?It was pushing a lot of water at 40amps today for an hour at the dock. ?I¡¯m still working on finishing up and organizing wires etc. but hopefully in the next few weeks I¡¯ll take her for a run out to the gulf to see if 40amps is 5knots or what. ?That¡¯s my hope. ?With two of my 350w solar panels connected it was putting roughly 10amps into the system so the batteries were only putting out 30amps. ? This was good to see even though today was best case for solar. ?No clouds at all.?
Hope this was helpful. On Feb 8, 2020, at 4:11 PM, gimmx via Groups.Io <gimmx@...> wrote:
?i am a marine service company in mexico wishing help in converting a 40 foot trimaran from diesel to electric propulsion.? ?Garth Jones.? ?I need some help and advice??
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After I assembled lithium iron phosphate?3.2v 90 ah cells in series and parallel to achieve 4 12v 360 ah cells. I put them in 4 heavy duty plastic boxes. Then installed the bms. Before inserting in box I wrapped the 12 v modules with large heat shrink wrap I then used a small torch to get a nice even seal.?In marine environments very important to not allow any moisture near the lithium cells. The bms is paired with my phone by using an app?This is very helpful to set your charging parameters If you are building your own battery system be sure to invest in a Flir type heat sensor. Very cool gadget that attaches to your phone to check out any possible bad connections. Check motor, controller, bus bars and all connections under load for heat issues It is a fun project. 40 ft sailboat racing sloop. I have to put some lead back in the boat because the batteries only weigh 90 lbs a piece 360 # vs 2 cycle diesel that we removed 800#. ?I hope this helps? Best regards, Larry Schmitz
On Saturday, February 8, 2020, 10:34 PM, L Schmitz via Groups.Io <terminalift@...> wrote:
I have the same set up. 10 kw ? 48 v system. Lithium iron phosphate cells in parallel??and seriesRunning tethered to the dock. 4 hrs. With lithium dyi??assembly ?70a continuous running. No heat issues?Next week is the real test. I will keep you posted??Should be able to run hull speed 6 hrs or more. Cheers? Best regards, Larry Schmitz
On Saturday, February 8, 2020, 7:20 PM, Larry Brown <elcapitanbrown@...> wrote: I got my motor and controller from Thunderstruck-ev.com. ?I just added the batteries and in my case generators for my idea of how I wanted to use the system. ?They have been extremely helpful along the way. ?There are other outfits out there that I cannot speak for. ?Only that these guys have been great for me. ?My trimaran is 38¡¯ x 22¡¯6¡±, 9k lbs. ?I chose the air cooled motor because I like the idea a bag won¡¯t get sucked up into my cooling line and overheat the motor. ?That being said I have yet to test mine in the Florida heat. ?I¡¯ll know more this summer how hard it is to keep cool. ?Ultimately I may have to switch. ?But I¡¯d rather try the option that would be simplest first.
There are more and more of us out here to give help as time goes. ?This is really the future of sailboat auxiliary I think. ?I¡¯m hopeful power boats are able to use it as well. ?As it stands I have a 2 to 1 reduction and I¡¯m going to be trying my 2 blade prop previously used for a 30hp Yanmar. ?It was pushing a lot of water at 40amps today for an hour at the dock. ?I¡¯m still working on finishing up and organizing wires etc. but hopefully in the next few weeks I¡¯ll take her for a run out to the gulf to see if 40amps is 5knots or what. ?That¡¯s my hope. ?With two of my 350w solar panels connected it was putting roughly 10amps into the system so the batteries were only putting out 30amps. ? This was good to see even though today was best case for solar. ?No clouds at all.?
Hope this was helpful. On Feb 8, 2020, at 4:11 PM, gimmx via Groups.Io <gimmx@...> wrote:
?i am a marine service company in mexico wishing help in converting a 40 foot trimaran from diesel to electric propulsion.? ?Garth Jones.? ?I need some help and advice??
|
Hi I bought a Torqeedo 4.0 with 4 12v 30 amp batteries. The boat is a 23ft Bayfield sailboat weighing 3500 lbs . I am wondering the approx. range I can get at 4 knots. The hull speed is 6 knots.? ?Thank you Graeme Ross
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On Sun, Feb 9, 2020 at 1:25 PM Graeme Ross via Groups.Io <graemealross= [email protected]> wrote: Hi I bought a Torqeedo 4.0 with 4 12v 30 amp batteries. The boat is a 23ft Bayfield sailboat weighing 3500 lbs . I am wondering the approx. range I can get at 4 knots. The hull speed is 6 knots.? ?Thank you Graeme Ross
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Graeme,
I ran some experiments on a a Catalina 22 with a Torqeedo 4R - which is probably the closest recorded data you may find with that motor...
At 4 to 4.5mph, I was burning 800-1000W.? ?At 48V, that's around 20A. Your range will depend heavily on your battery chemistry.? ?If you are using AGM or Lead Acid batteries, assume maybe 50% of your rated amperage - so a 130A bank might get you 65AH, so you should comfortably be able to get 3 hours of cruising, assuming you limit yourself to 1000W - which will hopefully push your boat close to 4mph.
Does that help?
Here are the test numbers from a run with the 48V Torqeedo on the C22: You can see how the required power increases dramatically above 4.5mph.? Hull speed for a 22' boat is about 6mph, if I did the math right...
Power? ? ? ? ? ? Speed 160w? ? ? ? ? ? ? ? 2mph 500w? ? ? ? ? ? ? ? 3.3mph 800w? ? ? ? ? ? ? ? 4.0mph 1000w? ? ? ? ? ? ? 4.5mph 1500w? ? ? ? ? ? ? 5.3mph 2000w? ? ? ? ? ? ? 5.8mph 3000w? ? ? ? ? ? ? 6.5mph
On Sunday, February 9, 2020, 01:12:19 PM CST, Graeme Ross <graemealross@...> wrote:
On Sun, Feb 9, 2020 at 1:25 PM Graeme Ross via Groups.Io <graemealross= [email protected]> wrote: Hi I bought a Torqeedo 4.0 with 4 12v 30 amp batteries. The boat is a 23ft Bayfield sailboat weighing 3500 lbs . I am wondering the approx. range I can get at 4 knots. The hull speed is 6 knots.? ?Thank you Graeme Ross
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?John? Thank you very much for the info. I think that this will work out perfectly. I will get a small generator to extend range for emergencies.? ?
Graeme,
I ran some experiments on a a Catalina 22 with a Torqeedo 4R - which is probably the closest recorded data you may find with that motor...
At 4 to 4.5mph, I was burning 800-1000W.? ?At 48V, that's around 20A. Your range will depend heavily on your battery chemistry.? ?If you are using AGM or Lead Acid batteries, assume maybe 50% of your rated amperage - so a 130A bank might get you 65AH, so you should comfortably be able to get 3 hours of cruising, assuming you limit yourself to 1000W - which will hopefully push your boat close to 4mph.
Does that help?
Here are the test numbers from a run with the 48V Torqeedo on the C22: You can see how the required power increases dramatically above 4.5mph.? Hull speed for a 22' boat is about 6mph, if I did the math right...
Power? ? ? ? ? ? Speed 160w? ? ? ? ? ? ? ? 2mph 500w? ? ? ? ? ? ? ? 3.3mph 800w? ? ? ? ? ? ? ? 4.0mph 1000w? ? ? ? ? ? ? 4.5mph 1500w? ? ? ? ? ? ? 5.3mph 2000w? ? ? ? ? ? ? 5.8mph 3000w? ? ? ? ? ? ? 6.5mph
On Sunday, February 9, 2020, 01:12:19 PM CST, Graeme Ross < graemealross@...> wrote:
Sorry I meant 130 amps On Sun, Feb 9, 2020 at 1:25 PM Graeme Ross via Groups.Io <graemealross= [email protected]> wrote: Hi I bought a Torqeedo 4.0 with 4 12v 30 amp batteries. The boat is a 23ft Bayfield sailboat weighing 3500 lbs . I am wondering the approx. range I can get at 4 knots. The hull speed is 6 knots.? ?Thank you Graeme Ross
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Larry,
Really interesting information.
I'm very curious about your sources of materiel (batteries, boxes, BMS, etc) and about your overall design & approach.
In particular, it's interesting to me that you employed a waterproofing solution similar to what's used for small packs built from cylindrical cells for things like electric bikes; i.e. shrinkwrapping.
ABYC standards require that the batteries be enclosed and insulated from potential short circuiting, requirements which it seems your approach probably fulfills.? You might try sending them an email asking the question, though.? I found them to be responsive.
Do you have four separate BMS units, or are your 12v modules tied together into one system?? Are you monitoring individual cell voltages?? I'm curious about how you're connecting the sensing wires to the batteries.? Does your BMS also implement cell balancing?? Are you monitoring cell temperature in any way?
I'm using 16S x 200Ah LiFePO4 prismatics and have also chosen to segregate them into four 12v units.? I'm running the sensing wires through waterproof (Molex) connectors, one connector per 12v group to facilitate breaking apart the pack so I can disconnect and carry each 4-cell package off the boat for winter storage or servicing.
I've built my 4-cell units into boxes to constrain the cells from expanding during charging and discharging, which I understand is important for preventing the internal structural changes that can arise inside an expanding cell.? Do you feel the shrink-wrapping you used is strong enough to accomplish this, or did you use constraining plates of some kind inside the package?
I have not yet found a correctly sized box to hold four of the 200Ah CALB cells I'm using.? What are the interior dimensions of the boxes you are using?? Are they hard plastic, or HDPE instead, & wall thickness, plz?
I hope you're not annoyed at all the questions!
[-tv]
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Larry, Really interesting information. I'm very curious about your sources of materiel (batteries, boxes, BMS, etc) and about your overall design & approach. In particular it's interesting to me that you employed a waterproofing solution similar to what's used for small packs built from cylindrical cells for thinks like electric bikes; i.e. shrinkwrapping. ABYC standards require that the batteries be enclosed and insulated from potential short circuiting which it seems your approach probably fulfills.? You might try sending them an email asking the question.? I found them to be responsive. Do you have four separate BMS units, or are your 12v modules tied together into one system?? Are monitoring individual cell voltages?? I'm curious about how you're connecting the sensing wires to the batteries.? Does your BMS also implement cell balancing?? Are you monitoring cell temperature in any way? I'm using 16S x 200Ah LiFePO4 prismatics and have also chosen to segregate them into four 12v units.? I'm running the sensing wires through waterproof (Molex) connectors, one connector per 12v group, to facilitate disconnecting and carrying each 4-cell package off the boat for winter storage or servicing. I've built my 4-cell units into boxes to constrain the cells from expanding during charging and discharging, which understand is important for preventing the internal structural changes that can arise inside an expanding cell.? Do feel the shrinkwrapping you used is strong enough to accomplish this, or did you use constraining plates of some kind inside the package? I have not yet found a correctly sized box to hold four of the 200Ah CALB cells I'm using.? What are the interior dimensions of the boxes you are using?? Are they hard plastic, or HDPE instead, & wall thickness, plz? I hope you're not annoyed at all the questions! [-tv] Thomas VanderMeulen "Grace O'Malley" Cape Dory 27 Monroe, Michigan
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I will send pictures. I found some great plastic heavy duty battery boxes at a marine supply store. Try west marine. Very sturdy boxes designed for batteries. I also found a husky storage box at Home Depot. I used in my golf cart project ? Nice size for 12 v set up. mil thickness is 7 shrink wrap. ?Used for covering large cargo for transport ??
?Terminalift LLC 9444 Mission Park Place Santee, CA 92071 Ph: (619) 562-0355 F: (619) 562-2060
On Sunday, February 9, 2020, 6:10:53 PM PST, THOMAS VANDERMEULEN <tvinypsi@...> wrote:
Larry,
Really interesting information.
I'm very curious about your sources of materiel (batteries, boxes, BMS, etc) and about your overall design & approach.
In particular, it's interesting to me that you employed a waterproofing solution similar to what's used for small packs built from cylindrical cells for things like electric bikes; i.e. shrinkwrapping.
ABYC standards require that the batteries be enclosed and insulated from potential short circuiting, requirements which it seems your approach probably fulfills.? You might try sending them an email asking the question, though.? I found them to be responsive.
Do you have four separate BMS units, or are your 12v modules tied together into one system?? Are you monitoring individual cell voltages?? I'm curious about how you're connecting the sensing wires to the batteries.? Does your BMS also implement cell balancing?? Are you monitoring cell temperature in any way?
I'm using 16S x 200Ah LiFePO4 prismatics and have also chosen to segregate them into four 12v units.? I'm running the sensing wires through waterproof (Molex) connectors, one connector per 12v group to facilitate breaking apart the pack so I can disconnect and carry each 4-cell package off the boat for winter storage or servicing.
I've built my 4-cell units into boxes to constrain the cells from expanding during charging and discharging, which I understand is important for preventing the internal structural changes that can arise inside an expanding cell.? Do you feel the shrink-wrapping you used is strong enough to accomplish this, or did you use constraining plates of some kind inside the package?
I have not yet found a correctly sized box to hold four of the 200Ah CALB cells I'm using.? What are the interior dimensions of the boxes you are using?? Are they hard plastic, or HDPE instead, & wall thickness, plz?
I hope you're not annoyed at all the questions!
[-tv]
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Graeme, By the way, if you're planning to burn about 1000A for a long time, a Honda 2200 generator would do fine to provide that (it defeats the purpose of the "green" effort, but at least you still have an electric motor.
If you do that, you could reduce the size of your battery bank significantly (saving a LOT of $$ if you're planning on Lithium).? Size the bank sufficiently for short outings, and use the generator any time you'd be out over an hour or so?
Just a thought.
John
On Sunday, February 9, 2020, 06:45:42 PM CST, Graeme Ross <graemealross@...> wrote:
?John? Thank you very much for the info. I think that this will work out perfectly. I will get a small generator to extend range for emergencies.? ?
Graeme,
I ran some experiments on a a Catalina 22 with a Torqeedo 4R - which is probably the closest recorded data you may find with that motor...
At 4 to 4.5mph, I was burning 800-1000W.? ?At 48V, that's around 20A. Your range will depend heavily on your battery chemistry.? ?If you are using AGM or Lead Acid batteries, assume maybe 50% of your rated amperage - so a 130A bank might get you 65AH, so you should comfortably be able to get 3 hours of cruising, assuming you limit yourself to 1000W - which will hopefully push your boat close to 4mph.
Does that help?
Here are the test numbers from a run with the 48V Torqeedo on the C22: You can see how the required power increases dramatically above 4.5mph.? Hull speed for a 22' boat is about 6mph, if I did the math right...
Power? ? ? ? ? ? Speed 160w? ? ? ? ? ? ? ? 2mph 500w? ? ? ? ? ? ? ? 3.3mph 800w? ? ? ? ? ? ? ? 4.0mph 1000w? ? ? ? ? ? ? 4.5mph 1500w? ? ? ? ? ? ? 5.3mph 2000w? ? ? ? ? ? ? 5.8mph 3000w? ? ? ? ? ? ? 6.5mph
On Sunday, February 9, 2020, 01:12:19 PM CST, Graeme Ross < graemealross@...> wrote:
Sorry I meant 130 amps On Sun, Feb 9, 2020 at 1:25 PM Graeme Ross via Groups.Io <graemealross= [email protected]> wrote: Hi I bought a Torqeedo 4.0 with 4 12v 30 amp batteries. The boat is a 23ft Bayfield sailboat weighing 3500 lbs . I am wondering the approx. range I can get at 4 knots. The hull speed is 6 knots.? ?Thank you Graeme Ross
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On Sun, Feb 9, 2020 at 10:43 PM john via Groups.Io <oak_box= [email protected]> wrote:
Graeme, By the way, if you're planning to burn about 1000A for a long time, a Honda 2200 generator would do fine to provide that (it defeats the purpose of the "green" effort, but at least you still have an electric motor.
If you do that, you could reduce the size of your battery bank significantly (saving a LOT of $$ if you're planning on Lithium).? Size the bank sufficiently for short outings, and use the generator any time you'd be out over an hour or so?
Just a thought.
John
On Sunday, February 9, 2020, 06:45:42 PM CST, Graeme Ross < graemealross@...> wrote:
?John? Thank you very much for the info. I think that this will work out perfectly. I will get a small generator to extend range for emergencies.? ?
Graeme,
I ran some experiments on a a Catalina 22 with a Torqeedo 4R - which is probably the closest recorded data you may find with that motor...
At 4 to 4.5mph, I was burning 800-1000W.? ?At 48V, that's around 20A. Your range will depend heavily on your battery chemistry.? ?If you are using AGM or Lead Acid batteries, assume maybe 50% of your rated amperage - so a 130A bank might get you 65AH, so you should comfortably be able to get 3 hours of cruising, assuming you limit yourself to 1000W - which will hopefully push your boat close to 4mph.
Does that help?
Here are the test numbers from a run with the 48V Torqeedo on the C22: You can see how the required power increases dramatically above 4.5mph.? Hull speed for a 22' boat is about 6mph, if I did the math right...
Power? ? ? ? ? ? Speed 160w? ? ? ? ? ? ? ? 2mph 500w? ? ? ? ? ? ? ? 3.3mph 800w? ? ? ? ? ? ? ? 4.0mph 1000w? ? ? ? ? ? ? 4.5mph 1500w? ? ? ? ? ? ? 5.3mph 2000w? ? ? ? ? ? ? 5.8mph 3000w? ? ? ? ? ? ? 6.5mph
On Sunday, February 9, 2020, 01:12:19 PM CST, Graeme Ross < graemealross@...> wrote:
Sorry I meant 130 amps On Sun, Feb 9, 2020 at 1:25 PM Graeme Ross via Groups.Io <graemealross= [email protected]> wrote: Hi I bought a Torqeedo 4.0 with 4 12v 30 amp batteries. The boat is a 23ft Bayfield sailboat weighing 3500 lbs . I am wondering the approx. range I can get at 4 knots. The hull speed is 6 knots.? ?Thank you Graeme Ross
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I have been experimenting with battery assembly projects for a couple years. My first opportunity was an electric forklift upgrade from lead acid to lithium iron phosphate ?The project really opened my eyes to the benefits of the battery chemistry. It was the golf cart upgrade that made me rethink battery installation for water proof. A few drops of overnight rain instantly corroded the lithium. I have used heat shrink on large objects for shipping . 7 mil blue roll material is very robust. Uline has it. Used after assembly before install. My battery boxes were bought to fit the 16S4P assembly ?It is important to fit a couple of space fillers between your batteries and box side. I shaped foam to fit snug. Thank you for your interest. Cheers?
?Terminalift LLC 9444 Mission Park Place Santee, CA 92071 Ph: (619) 562-0355 F: (619) 562-2060
On Sunday, February 9, 2020, 6:11:01 PM PST, THOMAS VANDERMEULEN <tvinypsi@...> wrote:
Larry, Really interesting information. I'm very curious about your sources of materiel (batteries, boxes, BMS, etc) and about your overall design & approach. In particular it's interesting to me that you employed a waterproofing solution similar to what's used for small packs built from cylindrical cells for thinks like electric bikes; i.e. shrinkwrapping. ABYC standards require that the batteries be enclosed and insulated from potential short circuiting which it seems your approach probably fulfills.? You might try sending them an email asking the question.? I found them to be responsive. Do you have four separate BMS units, or are your 12v modules tied together into one system?? Are monitoring individual cell voltages?? I'm curious about how you're connecting the sensing wires to the batteries.? Does your BMS also implement cell balancing?? Are you monitoring cell temperature in any way? I'm using 16S x 200Ah LiFePO4 prismatics and have also chosen to segregate them into four 12v units.? I'm running the sensing wires through waterproof (Molex) connectors, one connector per 12v group, to facilitate disconnecting and carrying each 4-cell package off the boat for winter storage or servicing. I've built my 4-cell units into boxes to constrain the cells from expanding during charging and discharging, which understand is important for preventing the internal structural changes that can arise inside an expanding cell.? Do feel the shrinkwrapping you used is strong enough to accomplish this, or did you use constraining plates of some kind inside the package? I have not yet found a correctly sized box to hold four of the 200Ah CALB cells I'm using.? What are the interior dimensions of the boxes you are using?? Are they hard plastic, or HDPE instead, & wall thickness, plz? I hope you're not annoyed at all the questions! [-tv] Thomas VanderMeulen "Grace O'Malley" Cape Dory 27 Monroe, Michigan
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Larry, since you have been experimenting with Li battery cells, what are your thoughts of using packs of the 18650 cells, as found packaged in some of the EV cars, such as the Tesla? There seems to be a high supply of used EV batteries on the market, some of the in 24V packs with BMS. For those of us not wanting to solder, weld, and package our own, are these worth the cost and weight?
Allan
Gemini 105 catamaran, Adagio
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Hi Allan,
I'd be curious to know what you see as the advantages of implementing packs assembled from 18650 or 21700 cylindrical cells.? I considered that option myself before ultimately settling on prismatics, but rejected it on several grounds.? First, was the uncertainty of the history of the used module, but other concerns included: how would I service the pack -- i.e. replace the cell -- if one of the cells goes completely bad; how do I monitor the BMS data (how would I capture and display the voltage and temperature data that may be collected by the embedded BMS); and due to weight and size, how do I physically install (move into an appropriate compartment, and then mount it per regulatory requirement)?
Using a minimum of 16 matched prismatic cells (to get to the 48VDC nominal needed to drive the 10kw motor from Thunderstruck), integration with available BMS systems (including the one from Thunderstruck, or the Orion Jr) seemed a lot more straightforward.
So far, the system is working exactly as expected on my test bench.? And I'm adding a variety of user interface options to make operation more user-friendly.? I doubt I could have done any of this using battery packs designed for automobiles, including Tesla, Leaf, Golf and so on.
There are sellers of 12v batteries built of 18650 cells, and incorporating their own BMS (or cell protection boards, which are NOT the same thing) in each unit.? I've thought about simply hooking four of these in series, but then I wouldn't have the same access to detailed operational and battery health information as a fully-integrated system provides.
Just my two-cents worth ...?
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Hi Allan,
Just wanted to throw in my two cents on Tesla battery comment.?
Telsa batteries are the most energy dense commercially available battery on the market today, twice as energy dense as lifepo4.? Packing all that energy in such a small space, makes them inherently much more volatile. Furthermore, the cell chemistry is much less stable than lifepo4. Handled properly they are incredibly safe, but a DIY boat setup is challenging.?
I wouldn't think twice about building an EV with Tesla batteries or even a dinghy, but a cruising boat, potentially miles from shore is another story.
With that being said, I believe are EV batteries are going to be a game changer for electric boats and DIY'ers. One day, it will be plug and play.?
Matt Foley? Sunlight Conversions Perpetual Energy, LLC 201-914-0466
On Monday, February 10, 2020, 09:45:23 AM EST, Adagio #573 via Groups.Io <awsmits@...> wrote:
Larry, since you have been experimenting with Li battery cells, what are your thoughts of using packs of the 18650 cells, as found packaged in some of the EV cars, such as the Tesla? There seems to be a high supply of used EV batteries on the market, some of the in 24V packs with BMS. For those of us not wanting to solder, weld, and package our own, are these worth the cost and weight?
Allan
Gemini 105 catamaran, Adagio
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Thanks, Matt and Thomas, for your quick and insightful views on EV batteries. Your points are well taken. I'm not a veteran of electric propulsion systems, and in fact, still power my catamaran with a Yamaha 25HP outboard, but I am intrigued by the electric propulsion idea. I'm a DIY'er, and I've researched most of the companies providing marine electrics, including Thunderstruck, but the power requirements and type of batteries are still a big question mark for me. Like everyone, I want it all, decent short-term cruising speed with the option of hybrid support for extended motoring, if necessary.
Thomas, tell me more about the prismatic cells, please. Can you send me some links to references?
Thanks, Allan
On Monday, February 10, 2020, 10:51:23 AM EST, Matt Foley <matt@...> wrote:
Hi Allan,
Just wanted to throw in my two cents on Tesla battery comment.?
Telsa batteries are the most energy dense commercially available battery on the market today, twice as energy dense as lifepo4.? Packing all that energy in such a small space, makes them inherently much more volatile. Furthermore, the cell chemistry is much less stable than lifepo4. Handled properly they are incredibly safe, but a DIY boat setup is challenging.?
I wouldn't think twice about building an EV with Tesla batteries or even a dinghy, but a cruising boat, potentially miles from shore is another story.
With that being said, I believe are EV batteries are going to be a game changer for electric boats and DIY'ers. One day, it will be plug and play.?
Matt Foley? Sunlight Conversions Perpetual Energy, LLC 201-914-0466
On Monday, February 10, 2020, 09:45:23 AM EST, Adagio #573 via Groups.Io <awsmits@...> wrote:
Larry, since you have been experimenting with Li battery cells, what are your thoughts of using packs of the 18650 cells, as found packaged in some of the EV cars, such as the Tesla? There seems to be a high supply of used EV batteries on the market, some of the in 24V packs with BMS. For those of us not wanting to solder, weld, and package our own, are these worth the cost and weight?
Allan
Gemini 105 catamaran, Adagio
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Hi Allan,
If you've already looked at the ThunderStruck website, then you may already have seen the type of prismatic cells I'm referring to.? They are the large, rectangular, plastic or aluminum encased battery cells with two terminals.? I settled on CALB, 200Ah cells.? The terminals take 8mm [M8] bolts, and wires and cables are connected using ring terminals.? Interconnecting the batteries in series is accomplished either with thin (1/6" or <) solid copper bars or battery cable depending on how the cells are oriented to one another.
Lithium Iron Phosphate [LiFePO4] chemistry is described in all authoritative sources I've found as the safest chemistry for marine use as also noted by Matt at Sunlight Conversions.? [I think I'm getting close to a 'plug-n-play' solution with what I'm putting together, Matt, but still developing!]
[-tv]
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THOMAS VANDERMEULEN
