How long does it take to fully charge a car battery that has no power?
3 Answers
Taking a 12V60Ah battery as an example, the charging method adopts constant voltage and current limiting for charging, with a constant voltage of 14.8V and a current limit of 15A for 16 hours. Below is an introduction to the battery: 1. Working principle: The battery, also known as a storage battery, is a type of cell that works by converting chemical energy into electrical energy. Typically, the battery people refer to is a lead-acid battery, which is mainly made of lead and its oxides, with sulfuric acid solution as the electrolyte. 2. Maintenance method: Avoid storing the battery in a discharged state. A discharged state means the battery is not charged in time after use, which can easily lead to sulfation. Lead sulfate crystals adhere to the plates, blocking ion channels, resulting in insufficient charging and reduced battery capacity. The longer the battery remains idle in a discharged state, the more severe the damage. When the battery is not in use, it should be charged once a month to extend its service life.
Last time my car wouldn't start, so I called a friend to help jump-start it, then drove to the repair shop to borrow a charger. The battery capacity was about 45 ampere-hours, and they used a 5-amp charger, which took me 10 hours to fully charge. The alternator charges more efficiently while driving—the car could start after half an hour of running, but to go from empty to full, it's safer to drive on the highway for 3 to 4 hours. I think it's important not to just focus on the charging time; checking whether the battery terminals are oxidized is also crucial, as corrosion slows down charging. Regular maintenance can help avoid such situations and significantly extend the battery's lifespan.
Charging time isn't fixed at all—it depends on the battery's capacity and the charger's power. I've learned some automotive knowledge. For instance, with a 60Ah battery, a 6A charger theoretically takes 10 hours, but actual efficiency is lower, often requiring an extra two hours. If relying on the car's alternator for charging, it outputs about 50A after starting. Driving at high speed for an hour can recharge 50%, but reaching a full 100% requires over five hours of steady driving. The battery's aging condition must also be considered, as older batteries charge more slowly. Regularly checking the voltage to confirm its health can prevent unexpected breakdowns.
