How To Clean Battery Corrosion in Your Car, Simply and Safely (2025)

Battery corrosion is a common problem that can prevent your car from functioning properly. Whether you're dealing with alkaline battery corrosion in a remote or car battery corrosion under the hood, knowing how to clean battery corrosion — and cleaning it promptly — is essential.

The white, powdery substance you see is typically a buildup of battery acid or other byproducts, which can damage the battery terminals or cables if left untreated.

Cleaning corroded battery terminals is a straightforward process, but it's important to handle it safely. By using everyday items like baking soda and lemon juice, you can restore your battery's performance and extend its lifespan. Here are step-by-step instructions to clean battery corrosion.

Contents

1. Step 1: Gather Your Supplies and Ensure Safety
2. Step 2: Disconnect the Battery Cables
3. Step 3: Neutralize the Corrosion
4. Step 4: Scrub with a Wire Brush
5. Step 5: Rinse and Dry Thoroughly
6. Step 6: Protect the Terminals With Dielectric Grease
7. Step 7: Reconnect the Battery Cables
8. Regular Maintenance

Start by assembling your supplies. You'll need:

For car batteries, make sure the engine is off, and wear gloves to protect your hands from battery acid. If you're working on a battery compartment in a device, remove the batteries before cleaning.

For car batteries, disconnect the battery cables, starting with the negative terminal. This step ensures safety and prevents accidental short circuits. Make sure that your wrench — or any other piece of metal in the engine bay — never touches both battery terminals at the same time.

Inspect the battery casing and cables for any visible damage before proceeding. Prolonged neglect may damage the connecting wires beyond their working state, in which case they'll need to be replaced by a professional.

Mix baking soda with a small amount of water to create a paste. Apply this paste to the corroded battery terminals or battery compartment to neutralize the battery acid. You can also mix in lemon juice or white vinegar, as these mild acids helps break down corrosion. Let the solution sit for a few minutes.

For bigger messes, auto parts stores generally stock spray cans of battery corrosion neutralizer, but the home remedy will work just as well in most cases.

Use a wire brush to clean battery terminals and the affected area in the battery compartment. Gently scrub to remove the battery terminal corrosion, focusing on areas with heavy buildup. For delicate electronics, use a soft cloth or an old toothbrush instead.

After scrubbing, rinse the area with a small amount of water to remove any remaining baking soda or residue. Distilled water works best for thorough rinsing.

Be cautious not to let water seep into the battery cells or electronics. Dry the battery terminals and surrounding areas completely with a clean cloth.

Once the battery terminals are clean and dry, apply a thin layer of dielectric grease on the battery terminals and cable contacts to prevent future corrosion. This grease acts as a barrier against moisture and air, which are primary causes of battery terminal corrosion.

In a pinch, petroleum jelly also makes for a good battery lubricant since it is nonreactive.

Reconnect the battery cables, starting with the positive terminal and then the negative terminal. Ensure the connections are secure to restore proper function. You may need to recharge the battery or jumpstart the vehicle in order to get it running again.

To prevent car battery corrosion or alkaline battery buildup, check your battery terminals and compartments periodically. Clean them as needed and ensure proper storage for devices to minimize exposure to extreme temperatures.

While storing a vehicle long term, you may want to consider removing the battery entirely and leaving it in a dry place. Use a "slow charger" like a battery tender to charge up the battery the next time you need to run the vehicle, rather than a harsh jump starter that wears out the battery with repeated uses.

We created this article in conjunction with AI technology, then made sure it was fact-checked and edited by a HowStuffWorks editor.