Cable Size and Voltage Drop

Question:

I have measured a 0,17 volt drop from my charger to the battery at 0,1C (28 amp). So no surprise I lose 0,4 volt at 0,3C (84 amp). Is this loss acceptable? Between the LFP battery and the charger I have 4 pieces of cable: from battery to fuse, from fuse to shunt monitor, from shunt monitor to load distributor and then to charger. The cable is a 50 mm square, length 2- 2,5 meter. Charger is configurable Mastervolt Chargemaster plus 12-100A. I could crank up voltage at the charger with 0,4volt?  - Mart

Answer:

Without a voltage sensor at the battery itself, the only way to offset voltage drop is to have larger sized cabling so that the high amps on the wire don’t cause the voltage to drop so much. Consider increasing the cable size between the charger and the battery to reduce the voltage drop. Make sure to also increase not only the positive wire but also the negative wire.