How to Use a Battery Tester

Somewhere in your house, there's a large box of batteries. Some of them are brand new, in the package, and some of them are lose. Instead of sorting through the box and testing them in strange combinations in the nearest electronic device, use a handheld battery tester.

Test and Sort Your Batteries

  1. Purchase a battery tester. Look for a spring loaded model that will test all forms of household batteries, including button cell, AA/AAA, C, D and 9V.

  2. Insert the battery into the tester. The tester will have markings to show which side is positive and which is negative. Match these up to plus and minus signs on the battery.

  3. Read the results. A good battery will display a full charge by lighting the entire display or moving the pin to the furthest side. A "dead" battery will light half or less of the display or move the pin only a small amount.

  4. Put each dead battery into a plastic baggie. Take these to a local home improvement or electronics store for recycling, as batteries should never be thrown in the trash.


  • Do not store batteries with the contacts touching each other, as this could cause a fire. Battery testers will not tell you if a rechargeable battery can be charged again.
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