How to Recharge a Dead Battery
Tips & Support
- Sponsor
- OPTIMA Batteries
- Location
- Glendale, WI
Car batteries never seem to die at a convenient time, but just because your car won't start, doesn't mean your battery needs to be replaced. If you know you deeply discharged your battery, it may just need to be fully recharged. Some older style chargers may have trouble recognizing deeply discharged batteries or delivering current to them, but OPTIMA's chargers can recover batteries that have been discharged down to 2.5 volts.
If you are using an older style charger that cannot deliver current to a dead battery or it only runs for a minute and then turns off, you may need to wire a second 12 volt battery with known good voltage in parallel (positive to positive, negative to negative). Doing this allows the older charger to see good voltage, while deliver energy to the deeply discharged battery.
Once the dead battery reaches a certain voltage level (usually above 10.5 volts), you can disconnect the second battery and continue charging with the charger until the battery measures at least 12.6 volts. If this seems beyond your ability from a technical standpoint, you can always take your battery to a local battery professional and ask them to attempt to charge the battery for you. We have a dealer locator (Find Your Store) on every page of our website. You can also watch this video that explains how to parallel charge your dead battery.
If you are using an older style charger that cannot deliver current to a dead battery or it only runs for a minute and then turns off, you may need to wire a second 12 volt battery with known good voltage in parallel (positive to positive, negative to negative). Doing this allows the older charger to see good voltage, while deliver energy to the deeply discharged battery.
Once the dead battery reaches a certain voltage level (usually above 10.5 volts), you can disconnect the second battery and continue charging with the charger until the battery measures at least 12.6 volts. If this seems beyond your ability from a technical standpoint, you can always take your battery to a local battery professional and ask them to attempt to charge the battery for you. We have a dealer locator (Find Your Store) on every page of our website. You can also watch this video that explains how to parallel charge your dead battery.