How Long Does it Take To Charge a Dead Battery?
Tips & Support
- Sponsor
- OPTIMA Batteries
- Location
- Glendale, WI
How long does it take to recharge a dead car battery? Anyone who gives you a fixed answer without knowing all the variables involved is not being honest. In simple terms, the two biggest variables are how much energy needs to be put into the battery and how fast the charger can put energy into that battery.
For example, a charger that charges a 20Ah battery at 10 amps should *in theory* fully recharge that battery in two hours from a complete discharge (chargers do not typically operate at 100% efficiency). However, if someone is attempting to charge that same 20Ah battery with a charger that has a maximum output of 1 amp, the time to a full state of charge could be at least 20 hours (probably closer to a full day in reality).
In this video, we explain that charger vs battery capacity math, using three different chargers, to help illustrate how much longer it may take to fully recharge a battery with a battery charger that has a lower amperage output. Hopefully, that will help you understand how long it may take for you to fully recharge a dead battery, once you understand how much energy needs to go into the battery and how fast the charger you are using can deliver that energy. If you'd like to take a closer look at OPTIMA's full line of battery chargers and maintainers, you can find them here.
For example, a charger that charges a 20Ah battery at 10 amps should *in theory* fully recharge that battery in two hours from a complete discharge (chargers do not typically operate at 100% efficiency). However, if someone is attempting to charge that same 20Ah battery with a charger that has a maximum output of 1 amp, the time to a full state of charge could be at least 20 hours (probably closer to a full day in reality).
In this video, we explain that charger vs battery capacity math, using three different chargers, to help illustrate how much longer it may take to fully recharge a battery with a battery charger that has a lower amperage output. Hopefully, that will help you understand how long it may take for you to fully recharge a dead battery, once you understand how much energy needs to go into the battery and how fast the charger you are using can deliver that energy. If you'd like to take a closer look at OPTIMA's full line of battery chargers and maintainers, you can find them here.