How to Prevent Rechargeable Batteries From Overcharging

Rechargeable batteries are the green option as far as batteries are concerned. These types of batteries can be used over and over again for about 1,000 charges. While it is important to keep your batteries charged, overcharging them can lead to their premature destruction. Careful monitoring of the recharger will prevent overcharging the batteries.

Things You'll Need

• Rechargeable batteries
• Battery charger
• Electrical outlet

Instructions

1. Make sure your batteries have little to no charge before you begin to recharge them. Place them into the battery charger. Plug the charger into the wall and charge for about an hour.

2. Check the batteries after an hour of charging. If the green light is on, signalling that they are fully charged, remove the batteries. If the red light is still on, check back again in 20 minutes. Repeat in 20 minute intervals until the green light comes on. Remove the batteries as soon as you see the green light is on.

3. Prevent overcharging your battery by setting a timer, like a cooking timer or the timer on your phone. If batteries are fully discharged, recharging will take at least an hour. So begin by setting your timer for one hour, and after that, time 20 minute intervals for an hour, then 10 minutes for an hour, and then 5 minutes for an hour until the batteries are charged. Charging times vary for each type of rechargeable battery, and it also depends on how discharged they are.

Tips & Warnings

• You may want to consider purchasing a slightly more expensive kind of charger that has an automatic turn-off or "trickle" charge once the batteries have been fully charged. These are perfect for busy households, businesses or people who cannot be there to promptly remove charged batteries.

• You can test how charged your batteries are with a digital multimeter, which can be purchased online or at any electronic or power tool supply store.

• Apply the proper care and maintenance of the battery as indicated with the owners manual of your charger, or instructions for rechargeable batteries found on the packaging. This will make the batteries and charger last longer.

• Remember to have your batteries at a low charge or no charge at all before putting them into the charger. This will help the batteries last longer.

• Perform a thorough inspection once a week of your rechargeable batteries. Discard any batteries that are leaking or have casing damage.

References

• CalRecycle.ca.gov: Rechargeable Batteries and Chargers
• GreenBatteries.com: FAQ's on NiMH Batteries and NiCad Batteries Compared to Heavy Duty Batteries