Enter State of Charge (SoC): Input the current SoC of your battery. A fully charged battery would have 100% SoC. Enter Depth of Discharge (DoD) ... 200Ah battery powering a 20A device, it would last around 10 hours. 48V Battery Life: For a 48V system, the same principle applies. A 48V, 300Ah battery powering a 30A appliance would last …