How to clean battery terminal corrosion

I usually use a vinegar based rust remover and an old toothbrush. Then brush on some WD40 and let it sit and dry overnight, i dont even rinse anything, just wait for it to soak in and dry

CLR also works well on battery corrosion after cleaning with CLR use wd40

I use 90%+ isopropyl rubbing alcohol, with a q-tip/cotton swab and a paintbrush. I also have a diamond needle kit, that can scrap off heavy corrosion. Sometimes I'll use an soft toothbrush. Baking soda has abrasive properties, yet it's still gentle on electronics. Apply a small amount to the affected areas of your device, and rub it in to remove stubborn traces of corrosion. Then wipe the surfaces down with cotton swabs or a slightly damp, lint-free cloth. White vinegar or lemon juice also works, Most household batteries contain bases, so acids will neutralize their discharge.

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Battery acid is reported to be neutralized by white vinegar. A Q-tip soaked in vinegar can be used to remove battery leaking.