How To Clean Battery Terminals

Calcification isn’t just what happens to dinosaur bones.

A photo of a car battery
Harrie Muis

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So you’ve come out to your car, cranked the starter, and found that your car is dead? And after popping the hood and inspecting the battery, you’ve found corrosion around the car’s battery terminals and are wondering how you clean them? Well, you’ve come to the right place!

Corrosion occurs around a car battery’s terminals because hydrogen gas leaks from the battery’s sulphuric acid within. When the gas hits the warm ambient air temperatures inside the engine bay, it forms a corrosive environment around the terminals.

Corrosion can interrupt the connection between the battery and the rest of the car, so it’s important to arrest the corrosion as soon as detected. If left untreated, the battery could unexpectedly die, and you’ll end up alongside the road with your thumb out. That’s where The Drive’s crack How To team comes in with its guide for how to clean battery terminals.

Toothbrushes ready? Just kidding.

Corroded battery.
Depositphotos

Corroded battery.

Cleaning Battery Terminal Basics

Estimated Time Needed: 30 minutes to an hour

Skill Level: Beginner

Vehicle System: Electrical

Cleaning Battery Terminal Safety

Working on your car can be dangerous and messy, as electricity can jolt you until the paramedics are needed. Here’s what you’ll need to ensure you don’t die, get maimed, or lose a finger and that you keep your jeans, shirt, and skin spotless.

Everything You’ll Need To (Keyword)

We’re not psychic, nor are we snooping through your toolbox or garage, so here’s exactly what you’ll need to get the job done. 

Tool List

Parts List

Organizing your tools and gear so everything is easily reachable will save precious minutes waiting for your handy-dandy child or four-legged helper to bring you the sandpaper or blowtorch. (You won't need a blowtorch for this job. Please don’t have your kid hand you a blowtorch—Ed.)

You’ll also need a flat workspace, such as a garage floor, driveway, or street parking. Check your local laws to make sure you’re not violating any codes when using the street because we aren’t getting your ride out of the clink.

Related Post: Best Car Batteries

Corroded battery terminals.
Depositphotos

Corroded battery terminal.

Here’s How To Clean Corroded Battery Terminals

The best way to clean your car’s battery terminals is to remove the battery completely. To know how to remove your car’s battery, check out The Drive’s step-by-step guide for How To Change a Car Battery

Let’s do this! 

Cleaning The Corroded Battery Terminals

  1. After you’ve removed the battery, take your skinny wire brush and dip it into the water/baking soda mixture.
  2. With your insulated gloves on, start removing the calcification, rust, and deposits around the battery terminals. 
  3. Continue to dip the brush and scrape the terminals until the calcification has been removed. 
  4. After removing the corrosion, check the battery’s posts for the same corrosion and calcification. If found, brush the terminals until they’re clean, as well. 
  5. If you believe your battery was leaking near the terminals, replace the battery. 
  6. Reinstall your battery, red cable to red terminal, black cable to black terminal.
  7. Check to make sure the car starts. 

You’re done! Congrats.

Get Help With Cleaning Battery Terminals From A Mechanic On JustAnswer

The Drive recognizes that while our How-To guides are detailed and easily followed, a rusty bolt, an engine component not in the correct position, or oil leaking everywhere can derail a project. That’s why we’ve partnered with JustAnswer, which connects you to certified mechanics around the globe, to get you through even the toughest jobs. 

So if you have a question or are stuck, click here and talk to a mechanic near you.

Cleaning Corroded Battery Terminals Pro Tips 

Over the years, The Drive’s editors have changed countless batteries. We’ve also seen our fair share of corroded battery terminals. Using our history, and mistakes along the way, here are our go-to pro tips for all the budding mechanics out there.

  • Like checking your oil or tire pressure, consistently inspect the battery and assess its condition to stay ahead of the corrosion. 
  • Most car batteries need to be replaced after around five years of use. Keep an eye out for that date.
  • Though it’s tough to install a battery incorrectly on modern cars, keep in mind that batteries need to be installed upright to avoid leaking any electrolyte solution.
Corroded battery terminals.
Depositphotos

Corroded battery terminals. 

How Often Do You Need To Clean Your Battery Terminals

Whenever you see the build-up of corrosion or calcification, which is rare on more modern cars. 

How Much Does It Cost To Clean Your Battery Terminals

So long as you have a wire brush, your out-of-pocket expenses are pretty much nil. If you don’t, you’ll likely spend about $10 for a wire brush and baking soda. 

Life Hacks To Cleaning Your Battery Terminals

Since you may not have access to the right tools or a friend you can bum a wrench off of, we compiled a list of our best hacks to make your life easier and drain your pocket less.

  • To protect against further corrosion, smear the terminals with petroleum jelly which will protect against corrosion and help maintain spark even in cold weather.

Featured Battery Cleaning Products

Odyssey Automotive

ACDelco Professional AGM

Diehard Advanced Gold AGM

Got a question? Got a pro tip? Send us a note: guidesandgear@thedrive.com