How Long Can a Car Battery Last Without Driving?
2 Answers
When a car is not driven, the battery can last for about 15 days. The functions of the car battery are: 1. When starting the engine, the battery supplies power to the starting system, ignition system, and electronic fuel injection system; 2. When the engine is stopped or at low idle, it powers the car's electrical equipment; 3. When the generator's output is insufficient, it can assist in supplying power to the electrical equipment; 4. It mitigates voltage surges in the electrical system, protecting the car's electronic devices; 5. It can store excess electricity generated by the alternator. Methods to maintain the battery include: 1. Start the car periodically to charge the battery; 2. When the electrolyte level is low, replenish it with distilled water or a specialized replenishment fluid; 3. Regularly check if the small holes on the battery cover are ventilated during daily driving; 4. Inspect the battery's positive and negative terminals for signs of oxidation; 5. Check all parts of the circuit for signs of aging or short circuits; 6. Turn off all electrical equipment when leaving the car.
Last year, I was away on a business trip for two months, and when I returned, my car wouldn't start at all. I had to call for roadside assistance to jump-start it. Later, the mechanic told me that generally, a car battery can last about 1 to 3 months when the car is left unused. It really depends on how old your battery is—mine was already three years old and not in great shape. The weather also plays a big role; in winter, with temperatures below -10°C, the battery might die in just a month, while in summer, it can last a bit longer. Additional devices installed in the car, like dashcams with 24-hour monitoring, can drain the battery quickly, so it's safer to unplug these devices if the car will be parked for a long time. If you plan to leave the car unused for more than six months, it's best to disconnect the negative terminal of the battery to protect the circuit.
