Lead-acid batteries, like any other batteries, have a different voltage at different stages of charge. For example, a 12V lead acid battery has a 12.73V voltage at 100% charge and an 11.36V voltage at 0% charge. These specific battery voltage states of charge (SOC) are found in lead acid battery voltage charts. You can use the measured voltage to determine how much % charge a lead-acid battery still has (how much juice is left).
To help you out, we compiled these 4 wet lead acid battery voltage charts you will find further on:
- 6V Lead-Acid Battery Voltage Chart (1st Chart). The 6V lead-acid battery state of charge voltage ranges from 6.37V (100% capacity) to 5.71V (0% capacity).
- 12V Lead-Acid Battery Voltage Chart (2nd Chart). The 12V lead-acid battery state of charge voltage ranges from 12.73V (100% capacity) to 11.36V (0% capacity).
- 24V Lead-Acid Battery Voltage Chart (3rd Chart). The 24V lead-acid battery state of charge voltage ranges from 25.46V (100% capacity) to 22.72V (0% capacity).
- 48V Lead-Acid Battery Voltage Chart (4th Chart). The 48V lead-acid battery state of charge voltage ranges from 50.92 (100% capacity) to 45.44V (0% capacity).

When compared to the lithium battery voltage charts here, we can quickly see that the lead-acid state of charge and corresponding voltage has a narrower range (12.73V to 11.36V for 12V lead-acid batteries vs. 14.4V to 10.0V for LiFePO4 batteries).
Here are the 4 lead-battery states of charge voltage charts for the most common lead-acid battery voltages (6V, 12V, 24V, and 48V):
6V Lead Acid Battery Voltage Chart (1st Chart)
6V Lead Acid Battery Charge Voltage: | Battery Capacity (Percentage): |
6.37V | 100% |
6.31V | 90% |
6.25V | 80% |
6.19V | 70% |
6.12V | 60% |
6.05V | 50% |
5.98V | 40% |
5.91V | 30% |
5.83V | 20% |
5.75V | 10% |
5.71V | 0% |
Here we see that a 6V lead acid battery has an actual voltage of 6V at a charge between 40% and 50% (43%, to be exact). The voltage spans from 6.37V at 100% charge to 5.71V at 0% charge.
It is also important to note that lead batteries have a depth of discharge (DoD) close to about 50%. That means that only about 50% of the full lead-acid battery capacity can be extracted from the battery.
Let’s move on to the most common 12-volt lead battery voltage chart:
12V Lead Acid Battery Voltage Chart (2nd Chart)
12V Lead Acid Battery Charge Voltage: | Battery Capacity (Percentage): |
12.73V | 100% |
12.62V | 90% |
12.50V | 80% |
12.37V | 70% |
12.24V | 60% |
12.10V | 50% |
11.96V | 40% |
11.81V | 30% |
11.66V | 20% |
11.51V | 10% |
11.36V | 0% |
Similarly to the 6V lead battery, we see that the 12V lead acid battery reaches the actually 12V voltage at the 40% to 50% range (43% is the exact capacity percentage).
At 100% charge, a 12V lead acid battery will have a 12.73V voltage.
At 0% charge, a 12V lead acid battery will have an 11.36V voltage.
This is a full 1.37V difference between 100% and 0% charge.
Onward to 24 lead acid battery chart:
24V Lead Acid Battery Voltage Chart (3rd Chart)
24V Lead Acid Battery Charge Voltage: | Battery Capacity (Percentage): |
25.46V | 100% |
25.24V | 90% |
25.00V | 80% |
24.74V | 70% |
24.48V | 60% |
24.20V | 50% |
23.92V | 40% |
23.62V | 30% |
23.32V | 20% |
23.02V | 10% |
22.72V | 0% |
We see the same lead-acid discharge curve for 24V lead-acid batteries as well; it has an actual voltage of 24V at 43% capacity.
The 24V lead-acid battery voltage ranges from 25.46V at 100% charge to 22.72V at 0% charge; this is a 3.74V difference between a full and empty 24V battery.
Let’s have a look at the 48V lead-acid battery state of charge and voltage decreases as well:
48V Lead Acid Battery Voltage Chart (4th Chart)
48V Lead Acid Battery Charge Voltage: | Battery Capacity (Percentage): |
50.92V | 100% |
50.48V | 90% |
50.00V | 80% |
49.48V | 70% |
48.95V | 60% |
48.40V | 50% |
47.84V | 40% |
47.24V | 30% |
46.64V | 20% |
46.04V | 10% |
45.44V | 0% |
Even this higher voltage 48V lead-acid battery has the same discharge curve and the same relative states of charge (SOC).
The highest voltage 48V lead battery can achieve is 50.92V at 100% charge. The lowest voltage for a 48V lead battery is 45.44V at 0% charge; this is more than a 5V difference between a full and empty lead-acid battery.
With these 4 voltage charts, you should now have full insight into the lead-acid battery state of charge at different voltages. Hopefully, you can now use the lead-acid battery voltage charts to adequately calculate the battery charges and/or voltages.
Thank You for a very comprehensive Battery Spec article in web.