battery sizing

How Do I Know What Size Battery To Get? Taking 1000 Watts from a 48-Volt battery requires the battery to deliver approximately 21 Amps. For a 12-Volt battery: 84 Amps DC x 3 hours = 252 A.H. For a 24-Volt battery: 41 Amps DC x 3 hours = 123 A.H. For a 48-Volt battery: 21