The Amp-hours determine how many watts your 12-volt battery can generate. For instance, a 12-volt, 100-AH battery may generate 1,200 Watts, or 1.2 kilowatts, at 12 volts multiplied by 100 AHs. The output of a 200 AH battery is equivalent to 2,400 watts, or 2.4 kilowatts. This is the optimum scenario with brand-new batteries and a 100% discharge rate.