[Serum]

if those batteries got loose contact one way or the other, or they have got a higher internal ressistance, you can damage your controller with braking. Because the motor is not able to store the energy back into the batteries, (that's what it does when you brake, it uses the internal resistance of your batteries for braking, with that comes that the energy is being stored back in to the batteriepack). so it would be fed from the both the motor and the batteries. That can kill the schulze.. And schulzes are known for that.

Those packs are cheap made, with thin tin plates, spotwelded.. Good till 15-20A, not for the 80-100A your system can eat..

I would not risc a controller that costs 20X as much then those batteries..

If you want the real thing, buy the GP3300's they deliver a bit more voltage on a high current load than the GP3700's (this voltage thing is what i heard from BK)