This is freqently, dangerously, wrong- and is missing critical information.

I saw no discussion of: * C rate * fuse selection * inverter precharge (capacitive loads) * cell level monitoring not all batteries are series compatible. * fail modes

But, in a sentence: No more than 100Ah and 12v for your first build.

Theres a million more things- like terminal preperation, torque specs, fire precations.