A fully charged 12V 100Ah LiFePO4 battery should read 14.2–14.6 volts under charging and settle to 13.2–13.4 volts at rest. Unlike lead-acid batteries, LiFePO4 cells maintain stable voltage during discharge, dropping sharply only when nearly… What Should a Fully Charged LiFePO4 Battery Read? Understanding 12V 100Ah LiFePO4 Batteries