By Sarah Witman
Sarah Witman is a writer focused on batteries and charging accessories. She has spent countless hours charging, discharging, and recharging batteries.
If you’ve owned an electronic device that has replaceable batteries—such as a remote control, a flashlight, a lantern, a wireless mouse, an electric pepper mill, or a child’s toy—you’ve probably had the misfortune of flipping open the battery compartment to find a whitish, crusty mess waiting for you.
Even the best household batteries are prone to rusting, corroding, and leaking chemicals, especially when they’re exposed to moisture or heat. Fortunately, there’s a simple way to clean up battery discharge, and chances are good you already have everything you need at home.
What you need
- Protective gloves: The chemicals inside batteries can burn skin.
- Safety goggles or other eye protection: Ditto.
- Cotton swabs: Finally, there’s a use for these that doesn’t risk damaging your eardrums.
- White vinegar or lemon juice: Most household batteries contain bases, so acids will neutralize their discharge.
- Rubbing alcohol: Isopropyl alcohol is a safe and effective way to clean electronics without leaving behind moisture and other residue.
- Pencil eraser, microfiber cloth, and/or compressed gas: These help clean up any fibers shed by the cotton swabs.
- Plastic bag or other disposable container: To get rid of the evidence.
How long will this take to clean?
Plan to spend about 10 minutes removing battery corrosion from your electronics.
Protect yourself from chemical burns
Not only is battery discharge messy—it’s also caustic. You don’t want to get it on your skin or in your eyes because it can cause permanent damage. During the cleaning process, glasses or goggles will protect your eyes from flying flecks of dried battery discharge, and protective gloves made of cloth or synthetic rubber will keep it from getting on your hands. As an added precaution, you might also want to wear long-sleeved clothing.
Neutralize the discharge with an acid
Most household batteries contain base chemicals, whether they’re single-use (alkaline) or rechargeable (nickel-based) batteries, so acids will neutralize them. After making sure the device is powered off, use a cotton swab to apply a few drops of lemon juice or vinegar to the affected area. The whitish, crusty discharge should start to fizz and disintegrate.
Note: Most cars run on lead-acid batteries, so you’ll need a different set of supplies to clean up car battery corrosion. And since these batteries are much bigger and more complicated to work with, you may want to consult a mechanic before tackling this job yourself.
Apply isopropyl alcohol
Isopropyl alcohol provides a one-two punch for cleaning electronics. It removes residue from other cleaning agents (in this case, lemon juice or white vinegar) that can gum up your electronics, without leaving behind any additional moisture.
It’s safe and effective, and it dries quickly. You’ll want to use the purest form of isopropyl alcohol you can find, so check the label on your rubbing alcohol or antiseptic wipes. The wipes that come with first-aid kits often contain just 70% isopropyl alcohol, which will work for external plastic or metal, but for internal stuff, 90% to 99% is preferable.
Wipe (or blow) it dry
Once you’ve cleaned the entire affected area, wipe it down with a microfiber cloth. You can also polish smaller sections with a pencil eraser. Finish up with a canister of compressed gas, designed specifically for cleaning electronics, to get rid of any pesky fibers left behind by the cotton swabs.
Let the device—especially internal components, like the battery compartment—dry completely before replacing the batteries and turning on the device.
Recycle your used batteries
When household batteries are tossed in the trash and end up in a landfill, the chemicals inside them leach into the soil and water systems, which is harmful to the environment. Fortunately, most single-use and rechargeable batteries—including AA, AAA, C, D, and 9 V—can be recycled.
To recycle corroded batteries, collect them in a plastic bag or other container to keep them from contaminating clean batteries. Look up drop-off locations near you, or find a mail-in program on sites like Earth911 and Call2Recycle.
Further reading
Yes, You Can (and Should) Recycle Batteries. Here’s How.
by Sarah Witman
If you have a container of spent batteries in your home that you don’t know what to do with, these are the best battery-recycling methods we’ve found.
How to Recycle Your Used Electronics
by Nick Guy
Are old computers, smartphones, or monitors taking over your closet? We’ll tell you how to recycle your tech, with privacy tips so you can do so safely.
How to Clean a Dishwasher of Mold and Other Suspicious Stains
by Ellen Airhart
Got mold on your dishwasher? We discovered that it might not technically be mold after all, but it’s still important to clean off. Here’s how.
How to Get Rid of Bedbugs
by Courtney Schley
Bedbugs can get the best of us, but there are steps you can take to beat them.
