1. Lead acid battery short circuit is mainly shown in the following aspects： 1.1 The open circuit voltage is low, and the closed circuit voltage (discharge) quickly reaches the end voltage. 1.2 When discharging at high current, the terminal voltage drops to zero rapidly.
To recover a lead acid battery, charge it for around 10 to 12 hours. Then, measure the terminal of the battery. After that, check the voltage of each cell and identify any cells with a voltage lower than 2 volts.
One of the most common reasons a lead acid battery shows 0V is sulfation. This happens because, inside a lead acid battery, there are lead plates that are coated with lead dioxide and are separated by a porous separator. When the battery is in use, the lead dioxide reacts with sulfuric acid and produces lead sulfate and hydrogen ions.
The resting voltage of a 12V lead acid battery refers to the voltage measured when the battery is not under load (i.e., not connected to any circuits or devices). After a period of rest, a fully charged battery should have a resting voltage around 12.6 to 12.8 volts.
The safest practice is to avoid discharging a 12V lead acid battery below 50% of its capacity, which corresponds to around 12.0 volts. Discharging below this threshold on a regular basis can dramatically reduce the battery’s usable life.
To identify the bad cells in a lead acid battery, follow these steps: Charge the battery for at least 12 hours and then allow it to rest for 10 minutes. Open the battery caps and fill each compartment with water to within optimum levels. Measure the terminal voltage of the battery.