What is normal voltage for a fully charged car battery?

• A. About 12.6 volts
• B. About 11.5 volts
• C. About 13.2 volts
• D. About 14.4 volts

Answer: (A)

A fully charged car battery, when measured with no load and after any surface charge has dissipated, should read about 12.6 volts. This comes from the chemistry of a lead‑acid battery, which has six cells each contributing roughly 2.1 volts when fully charged, totaling around 12.6 V. If you read much lower, like 11.5 V, the battery is discharged or aging. The higher readings come from the charging system: with the engine running, the alternator pushes voltage up to about 13.8–14.4 volts to charge the battery and run electrical loads, which is not the resting voltage of a fully charged battery. So, for a fully charged battery at rest, aim for about 12.6 volts.