How to Check for Faulty Rechargeable AA Batteries
- 1). Inspect the battery terminals, or +/- ends, of the rechargeable batteries. The terminals of the battery are the most common sites of leaking or corrosion. If leaking or corrosion is visible, immediately discard the batteries.
- 2). Feel and examine the body of the battery. If you notice or feel any large dings, dents or lumps, discard the battery. A large dent or bump can indicate the battery cells inside the rechargeable battery are damaged.
- 3). Examine the entire battery for signs of leakage, corrosion or rusting and discard if you find any. A leaking battery may leave behind a slightly watery or sticky reside on your fingers. A corroded battery will have a visible green or white powder, while a rusty battery will have rust, or an orange-red color, anywhere on the battery.
- 4). Charge the batteries using a AA battery recharger for the type of rechargeable batteries you own. The most common types of AA rechargeable batteries are NiMH, NiCD and Li-Ion batteries. If they do not recharge, discard them.
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