What are the methods to test the condition of a car battery?

[VanAlex]

Methods to test the condition of a car battery include: 1. Visually inspect the battery for any signs of leakage, swelling, bulging, or damage; 2. Connect a load, such as a 12v motor, to see if it operates—failure to operate indicates a battery issue; 3. Directly connect the battery to a charger—if the charger shows a green light and the battery heats up, it indicates a problem; 4. Use a multimeter to measure the voltage and check if it matches the rated voltage; 5. Use a battery tester for direct testing. Battery maintenance methods include: 1. Turn off lights, audio, and air conditioning before shutting down the engine; 2. Avoid leaving the vehicle unused for extended periods—regular driving is recommended; 3. Periodically clean the exterior of the battery; 4. Regularly test the battery's charge retention capacity.