What is the normal SOC for a car battery?
2 Answers
Under normal circumstances, the battery voltage before starting the car should be between 11.8V and 12.8V, and after starting, it should be between 13.2V and 14.8V. As long as the voltage during startup is not lower than 11V, it is considered normal. Signs of a failing car battery are as follows: 1. Difficulty starting the car: If the car suddenly has difficulty starting without any other factors, it may be a sign that the battery is about to fail. 2. Dimming lights when the car is idling: For example, when stopping at a red light or temporarily parking, the headlights suddenly become dim. This is because the charging power of the engine decreases when idling. 3. Battery warning light comes on: When the battery warning light comes on, it is a reminder for the owner to go to a repair shop for battery maintenance and testing. 4. Normal driving most of the time, but occasionally the car has no power after parking and restarting: This is because when the battery is nearing the end of its life, the starting current is insufficient, causing an increase in oxide on the battery terminals, resulting in a complete loss of power.
The SOC (State of Charge) of a car battery should ideally be maintained between 80% and 100%. Having driven for over a decade, I usually rely on the battery indicator on the dashboard to monitor it without much issue. If the SOC drops below 50%, you might encounter problems when starting the vehicle, such as difficulty igniting or dim lights, especially in older cars. To keep the SOC at a higher level, I recommend driving longer distances every few days to recharge or using a charger for maintenance if the car is parked in a garage. If the car remains unused for extended periods, the SOC will drop faster, so regular checks are necessary to avoid surprises.
