How to Clean Battery Corrosion from Devices and Remotes

Open a TV remote, flashlight or kid's toy that's been sitting in a drawer and you might find crusty white or blue-green buildup on the battery contacts. That's battery corrosion, and it can stop the device from working. Here's how to clean battery corrosion safely from household devices.

Quick answer: Wear gloves and eye protection. Remove the batteries and dispose of them properly. For common alkaline batteries, dab the crusty contacts with a cotton swab dipped in white vinegar or lemon juice to neutralize the residue, scrub gently with an old toothbrush, wipe with a little rubbing alcohol, and let it dry completely before inserting new batteries.

Safety First

Wear disposable gloves and safety glasses. Battery residue can irritate skin and eyes.
Don't touch your face; wash hands afterward.
Work in a ventilated area.
If a lithium-ion battery (phones, laptops, power tools) is swollen, leaking, hot or damaged, don't try to clean it. Stop using the device and take it to a battery recycling or electronics drop-off.
Car batteries contain sulfuric acid and use a different method (baking soda solution); follow the vehicle manual or have a mechanic help.

What You'll Need

Gloves and eye protection
White vinegar or lemon juice
Cotton swabs and an old toothbrush
Rubbing alcohol (isopropyl)
Fine sandpaper or a pencil eraser (for stubborn spots)
Paper towels

Step-by-Step (Alkaline Batteries: AA, AAA, C, D, 9V)

Remove the batteries carefully and place them in a plastic bag for proper disposal or recycling.
Brush off loose crust with a dry toothbrush over a paper towel.
Neutralize: alkaline leakage is basic, so a mild acid helps. Dip a cotton swab in white vinegar or lemon juice and dab the contacts. You may see a little fizzing.
Scrub gently with the toothbrush. Don't flood the device; use just enough liquid.
Clean off residue with a cotton swab dampened with rubbing alcohol, which evaporates quickly.
Polish stubborn spots with a pencil eraser or a little fine sandpaper until the metal looks bright.
Dry completely for an hour or so before inserting fresh batteries.

When the Device Still Won't Work

Check that the springs and contacts touch the batteries firmly; gently bend a flattened spring outward.
Corrosion may have spread into wires or the circuit board. For valuable electronics, ask a repair shop.

Battery Leaked on Your Skin or a Surface?

Rinse skin with plenty of water and soap. If it gets in your eyes, rinse with water for at least 15 minutes and seek medical advice. Wipe surfaces with a damp cloth, then a little vinegar, then water.

How to Prevent Corrosion

Remove batteries from devices you won't use for a few months.
Don't mix old and new batteries or different brands in the same device.
Store batteries in a cool, dry place.
Replace all batteries in a device at the same time.

Dispose of Batteries Responsibly

Many communities in the US and Canada have battery recycling drop-offs at hardware and electronics stores. Check local rules.

FAQ

Can I use baking soda on AA battery corrosion?

Baking soda is for acid leaks (like car batteries). Household alkaline battery leaks respond better to vinegar or lemon juice.

Is battery corrosion dangerous?

It can irritate skin and eyes, so handle it with gloves and eye protection.