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Read up on and analyze previous revs of UV Cutoff
Add a charging circuit?
Will also require active protection (over-voltage, over-temperature, and overcurrent, see section 8.3.B in ASC regs)
Make UV cutoff compatible with aux battery?
Use the same PCB for both batteries, but some passives might need to change to adjust reference voltages, etc.
OO: If we have a set of passives for the auxiliary, in conjunction with the existing passives for the actual battery, and use jumpers that we can solder or de-solder in order to connect the UV Cutoff to any or both batteries when we want.
Have two sets of passives: two sets of VBAT load switches, buck converter, and jumpers after each of these.
AUX battery powers fan and horn but when that runs out, switches to main pack
the main pack is may be 24V AUX is 12V, maybe we will use a 24V aux if main battery is 24 and use less fewer circuitry
Replace the high-side P-channel MOSFET reverse polarity protection with a low-side N-channel MOSFET for reverse polarity protection?
N-channels have a lower on resistance, so it would be more efficient. It would also be safer on the low side. If the battery was connected backwards with a P-channel FET, then 12 V will be connected to gnd, which is a larger net so it's more likely to accidentally touch something conductive and cause a short circuit.
The fuse could probably be replaced with an e-fuse to have a more precise current limit.
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