Lead-Acid Battery Voltage Chart For 6V, 12V, 24V, 48V Batteries

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).
lead acid battery voltage charts
Lead acid battery is comprised of lead oxide (PbO2) cathode and lead (Pb) anode. The medium of exchange is sulphuric acid. Most common example of lead-acid batteries are car batteries.

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.

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