Lead-Acid Battery Charging Methods.
Batteries are charged by either the constant voltage or constant current method.
1. In the constant voltage method a motor generator set with a constant, regulated voltage forces the current through the battery. In this method, the current at the start of the process is high but automatically tapers off, reaching a value of approximately 1 ampere when the battery is fully charged. The constant voltage method requires less time and supervision than does the constant current method.