Lead Acid Battery Voltage Chart

When it comes to lead-acid batteries, one of the most important things to know is voltage. Measuring voltage is a critical part of maintaining the health and longevity of your battery. Being familiar with a lead acid battery voltage chart can help you to understand the state of your battery at a glance.

Lead Acid Battery Voltage Chart

Charge Level 12V 6V 2V
100% 12.7V 6.35V 2.1V
75% 12.4V 6.2V 2.05V
50% 12.2V 6.1V 2V
25% 12V 6V 1.95V
0% 11.9V 5.9V 1.9V

What voltage should a fully charged lead acid battery be?

A fully charged lead-acid battery should measure at about 12.6 volts. This is the voltage when the battery is at its fullest and able to provide the maximum amount of energy. When fully charged, a 12-volt battery will have six cells each containing 2.1 volts.

What voltage is too low for a 12-volt battery?

If the voltage drops below 11.8 volts, it is considered too low for a 12-volt battery. At this point, the battery is essentially dead and unable to start a vehicle or other applications that require a steady flow of energy.

What voltage is 50% of a 12v battery?

When a 12-volt battery is at 50% capacity, it should measure at approximately 12.0 volts. It is important to keep track of your battery’s voltage over time to ensure it has enough energy to power your applications.

What is the lowest safe voltage for lead acid battery?

The lowest safe voltage for a lead-acid battery is 11.8 volts. Going below this voltage can cause permanent damage to the battery and make it impossible to recharge. This can also cause the battery to lose its maximum capacity and make it unable to hold a charge for long periods.


Knowing the numbers on a lead-acid battery voltage chart is critical to keeping your battery in good shape. By tracking your battery’s voltage, you will be able to catch potential problems before they become serious and make sure that your battery is operating at its maximum capacity. Remember to always be safe when working with batteries and take proper precautions to avoid injury.

About the author, Phil Borges

Phil Borges is a battery aficionado. He's written extensively about batteries, and he loves nothing more than discussing the latest innovations in the industry. He has a deep understanding of how batteries work, and he's always on the lookout for new ways to improve their performance.