The anode and cathode of a battery are separate, so electrons can’t flow from one side to the other freely. When a battery terminal is connected through a conductor, the electrons can move from the anode to the cathode, which produces voltage.

Battery voltage refers to the potential difference between the positive and negative electrodes. The greater the potential difference, the higher the voltage. A volt is a unit used to measure the battery voltage.

The battery voltage varies depending on the charge of the battery. A battery’s voltage is higher when it is fully charged than when it is running low or empty.

The Voltage of Lithium Battery

The nominal voltage will vary depending on the cathode material of the lithium battery. For example, the nominal voltage of a lithium cobalt oxide battery is 3.7V and that of a lithium iron phosphate battery is 3.2V.

And the voltage loss depends on the battery type. A 12-volt sealed lead-acid battery will provide about 12.89 volts at 100% capacity, and about 11.81 volts at 20% capacity. A 12-volt lithium iron phosphate battery will provide about 13.6V volts (the resting voltage) at 100% capacity and about 12.9 volts at 20% capacity.

How to Measure Battery Voltage

Measuring the battery voltage is critical, allowing you to confirm the battery’s state of charge. You can use a multimeter or a battery monitor to measure the battery voltage.

Those devices use sensors to measure the potential difference between two points and then display the voltage value on the screen.