What Voltage Should A Fully Charged 12v Battery Read. The ideal car battery voltage with the engine running is between 137 and 147V. Battery voltage reacts highly to charging and discharging.
So a 12volt battery will measure at about 129 volts when its fully charged and about 114 volts when it is fully discharged. In reality the amount is not exactly 12 volt. The actual resting voltage or the voltage a battery will settle at 12-24 hours after being removed from the charger is closer to 21 volts per cell or about 64 volts for a 6v battery and 127 volts for a 12v battery.
Any voltage above 129 volts is a good indicator that your battery has excessive voltage.
In reality the amount is not exactly 12 volt. So a 12volt battery will measure at about 129 volts when its fully charged and about 114 volts when it is fully discharged. If the reading is 1245 volts or less the battery is low and needs to be recharged. Volts on a resting battery means its 19 jun 2017 when the is fully charged.
