Keeping a clean battery is important for good Car battery maintenance.

When you open your hood to check fluid levels, also look at your battery. If you see any  corrosion, it should be cleaned. Good car battery maintenance will help prevent unwanted problems while driving.

Even a "maintenance free" automotive battery can build up corrosion.
If the corrosive build up is not cleaned off, it will interfere will the electrical connection and can eat away at the wires and  terminals, to the point of needing replacement.

What causes corrosive build-up on the battery terminals, as seen in the picture, is a combination of hydrogen gas produced by the chemical reactions in the battery, and the dirt and sediment on the terminals.

For this reason keeping a clean battery before corrosion occurs will help prevent the problem from starting.
keeping grease or petroleum jelly on the  terminals will prevent battery acid build up as well.

Other car battery maintenance may include putting water in the  cells when needed.

However, very few car batteries today require this type of car battery maintenance, and are thus called "maintenance free" batteries.

Check with your mechanic or car dealer if you aren't sure what type of battery your vehicle has.

Any car battery maintenance requires safety precautions.


put on eye protection
such as safety glasses or goggles.
Remember a battery produces both hydrogen and oxygen gases, which may trigger it to explode if there is a spark or too much heat.

The acid from the battery could do serious eye damage and cause blindness. It would be well worth the protection if your sight was saved by eyeware from an accidental mishap.

Ear protection is also advised.
Some people have had damaged hearing because of how loud the explosion of an automotive battery was while they were working on it.

gloves will protect your hands from the battery acid.

Remove all metal jewelry before working on your car battery
If you accidentally let your metal wrench come in contact with both the negative and positive terminals before they are disconnected, the spark could cause rings and other metal on you to heat up in seconds, giving you severe burns.

Wear clothes which you wouldn't mind throwing out
Battery acid could eat a hole in your clothes.
Rinse any clothing that might have gotten acid on them in baking soda and water. This will neutralize the acid and keep it from burning a hole in your clothes.

Items used for cleaning:

1. Wire or bristle brush

2. A can of soda or a solution of baking soda and water
( one part water to three parts soda for a paste, but 3 tablespoons of soda to two cups water also works well.)

3. Petroleum jelly

4. Towels and rags, ones you wouldn't mind throwing away if too much battery acid gets on them.

The quick way to clean corrosion off your battery, especially if you are in a place where you don't have tools or time to disconnect the battery from the terminals is to find a can of soda and pour it on the post and terminal where corrosion build up is.

You will see it bubble as it neutralizes the acid. Make sure to rinse thoroughly with water afterward.

as you can see in the pictures below it does a good job of cleaning the corrosion off the battery posts and terminals, however, it doesn't get all the corrosion from in between the post and the terminals.



When you do have time for complete car battery maintenance and cleaning, take the  terminals off the battery and clean in between the posts and terminals.

To clean the posts and terminals thoroughly, you will need either an adjustable wrench (left), or even better, a socket wrench (right,) to disconnect the terminal connectors from the posts.

ALWAYS disconnect the negative post first. And reconnect it LAST.

The reason is, the negative post is the post grounded to the metal frame of the vehicle, giving the electricity a path to travel.
The Positive post is not grounded to anything.

If you disconnect the positive terminal while the negative side is still connected and your wrench touched some other metal part of the car while touching the post,
it could spark, cause an explosion or burn you quite badly because your wrench would heat up very quickly. Jewelry would also get very hot and burn you.

All rings and watches should be removed before ANY car battery maintenance is performed.

The screw that holds the terminal to the post is on the side of the battery post as in the picture on the left.

Keeping the cover or a rag over the positive post will prevent accidental contact with the wrench, also preventing burns and explosion while loosening the negative side.

Remember "lefty loosey", "righty tighty".

Loosen the nut, be sure to use the correct size wrench or socket, otherwise it is very easy to round off the nut.

I found a 10mm socket fit just right.

You may need to wiggle the terminal connector or use a screw driver to lift it off the post.

Once the connector is off the post, make sure you push it far back from the post so no contact is made between the connector and the post while cleaning.

to clean the inside of the terminal connector, if your wire or bristle brush doesn't fit well to clean it, put some baking soda paste on a rag and use your finger over the rag to get the residue out, as seen in the picture on the right.

After scrubbing the posts and terminals and seeing no more corrosive residue, make sure the posts are completely dry before reconnecting. Moisture will cause corrosion to build up again faster.

Also rub a little petroleum jelly or some kind of grease on the posts to prevent acid build-up.

Reconnect the negative terminal LAST to prevent sparks and explosions!

One last thing to remember, while you may want to throw away the rags that got battery acid on them, make sure you clean off your tools you used well, maybe even with baking soda.

You would hate to have expensive tools sitting around being eaten by sulfuric acid that was left on them after cleaning a battery!

Regular car battery maintenance and cleaning will help keep your car running!

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