What is the full charge voltage of a car battery?

[Fernando]

Car battery full charge voltage is between 12 to 13 volts. Precautions for battery charging include: 1. Battery voltage below 10% of the rated voltage will cause battery drain; 2. Avoid water entering the battery during charging; 3. Connect directly to the battery for charging, avoid removing the battery to prevent data loss. Car battery maintenance methods include: 1. Start the car regularly to charge the battery; 2. Add distilled water or special replenishing fluid when electrolyte is low; 3. Frequently check if the small holes on the battery cover are ventilated during daily driving; 4. Check for oxidation on the positive and negative terminals of the battery; 5. Inspect all parts of the circuit for aging or short circuits; 6. Turn off electrical equipment when leaving the car.