Charging a regular car battery typically takes between 10 to 24 hours to fully charge using a standard charger with a current of about 4 to 8 amperes. To charge enough to start the engine, it usually takes around 2 to 4 hours
. The exact charging time depends on several factors including:
- Battery capacity (measured in ampere-hours)
- Charger output (amperes)
- State of charge (how discharged the battery is)
- Charging method and charger type (standard, trickle, or multi-stage chargers)
- Battery type and condition
For example, charging a 48 amp-hour battery at 2 amps takes about 24 hours, while charging at 6 amps reduces that time to about 8 hours. Higher amperage chargers (e.g., 20 amps) can charge a battery faster but risk damaging the battery if it is deeply discharged
. Charging a car battery while driving is much slower and less effective. It can take 4 to 8 hours of highway driving to significantly charge the battery, but the alternator is not designed to fully recharge a battery while driving, so it will never reach 100% charge on the road alone
. For electric car batteries, charging times vary widely depending on battery size and charger power, ranging from about 30 minutes on a rapid charger to 8 or more hours on slower chargers, but this is a different type of battery and charging system than a conventional car battery
. In summary:
- Slow charging (4-8 amps): 10-24 hours for full charge
- Enough charge to start engine: 2-4 hours
- Charging while driving: 4-8 hours at highway speeds, but never fully charged
- Fast chargers can reduce time but risk battery damage if not used properly
Slow charging is recommended to prolong battery life
