How to Check if a Car Battery is Good or Bad?

[KeiraMarie]

Here are the methods to check the condition of a car battery: 1. Check for battery swelling. When a battery swells, it is due to increased internal pressure under high temperatures, causing the battery's pressure relief valve to open automatically. Once the pressure relief valve opens, it accelerates the loss of water from the battery. Excessive water loss leads to decreased battery activity, making it prone to issues such as casing overheating, bulging, and deformation during charging—a phenomenon known as battery swelling. 2. Inspect the battery surface color. Regularly check around the battery terminals for any white or green powdery substances. These are actually oxides from the battery. The presence of such oxides indicates that the battery's performance is starting to deteriorate. 3. Measure the battery voltage. Use a multimeter to measure the voltage between the battery's positive and negative terminals (preferably when the car is cold). A reading above 12V indicates normal performance, while a reading below 12V suggests poor battery performance. 4. Listen for sounds. If you hear unusual noises when starting the car, it indicates severe battery depletion, and the battery should be replaced promptly.