Aaron,
I can say from experience that I would not put either a battery or an antenna tuner in the device housing.
The best antenna is a good antenna. I dismantled my existing antennas last spring. (2-element 5-lane Quad 17 m high and 20.8 m Vertical). Then when sBitx_v2 came out in April, I bought one. I was very busy all year, so I only built an antenna in November.
A delta loop antenna that is installed vertically and slightly slanted. It is very well-proven and works well on 3 lanes.
Because it's a loop, it's low noise. The total length of the loop is 43.8 meters. I feed it at the highest point (10m) where there is a 2:1 balun, followed by a 1:1 balun. These are up at the base of the antenna.
Characteristics: 1:1.3 at 7MHz, I can supply 12-15W here.
At 14MHz 1:1.05 here I can supply 20W, while at 21MHz 1:1.2 here I can supply 10W. In ft8 mode, I am constantly watching this.
My power supply has a current limiter, it is set to 6.00A, I use it from 12.5V. Yes, the fetek IRFZ24N, which I managed to destroy using the initial battery, since then I only use it in current limiting mode! A battery current limiter would need to be built.
My sBitx is v2, manufactured last April, on which I had to make some modifications. I wrote about them in the forum. I currently have over 1500 ft8 QSOs and am close to 100 dxcc.
I considered the heat dissipation of the device important when I replaced the mica with an AlN insulator, and I also use an external fan that works continuously. It is wedged between the cooling fins and can be easily removed at any time. This is a so-called silent fan that consumes 40 mA.
So the bottom line is that I would not install a battery or an antenna tuner because of the above.
--
Gyula HA3HZ
HA3HZ