A. There are a few ways to tell if your battery needs a 24 volt lithium battery charger. One way is to look at the voltage of the battery. If your battery is 12 volts then it does not require a 24 volt lithium battery charger. You can also check the amp-hour rating of your battery, which is typically found on the sticker on top of the battery. A 24 volt lithium battery charger will be needed for batteries with an amp-hour rating over 100 amps.