What is the white stuff on my terminals

What is the stuff on my terminals?


So you’ve popped the bonnet of your car, and you’re staring at a bunch of wires and metal things. You can identify most of them, but there’s one that’s confusing: The white stuff on your battery terminals. What is it? Why does it happen? Is it bad? Here we’ll answer these questions and more!

Calcification(the “white” stuff)

Calcification is a normal process in batteries. It’s caused by the electrolyte in your battery, which is made up of acid and water. The acid combines with the minerals on your battery terminals, forming a white crusty substance that can be removed with a wire brush or even just hot water from the kettle.


The white stuff on the terminals is actually a chemical reaction between the battery and the acid inside. Inside every lead-acid cell is sulfuric acid, which gives off hydrogen gas when it’s discharged. When you recharge your battery with a charger, you’re forcing that hydrogen back into the battery as gas again 

As for what causes that white stuff to form, calcium and magnesium are two ingredients that come from either part of the battery itself or from other substances around it. If you leave the white build up to get worse it will eventually eat away at the terminal causing it to need to be replaced.

Problems caused by calcification

  • Battery life is shortened.
  • Battery performance is reduced.
  • The battery is less efficient.
  • The battery is more difficult to charge and maintain.

How to prevent calcification

  • Keep batteries clean and dry, use wd40 or Vaseline to treat the area after cleaning away the white residue. The white powder you see is a result of a chemical reaction between the battery acid and electrolytes, so keeping your batteries clean will help prevent it from forming.
  • Don’t overcharge them or let them get too low on power or water levels for maintainable batteries—these things can cause damage that will result in calcification!

Are batteries recyclable

Recycling batteries is a great way to do your part in reducing the amount of toxic materials that go into landfills. Unfortunately, many people don’t know that batteries can be recycled—and many more don’t realize how easy it is to recycle them.

To Recycle your battery simply bring it to us! We will send the battery for recycling with our dedicated licensed recyclers.

The white stuff on your battery terminals is normal and is called “calcification”. It should be removed regularly to keep your battery running at its best.

Calcification is a natural process that occurs in all batteries and can lead to problems. It is caused by a chemical reaction between the battery acid and the battery terminals, which causes them to become coated with a white powdery substance. This coating can reduce performance and shorten your battery’s life.

To keep your battery running at its best, you should regularly clean off this white powdery substance by cleaning your terminal connections with boiling water and then applying WD-40 or vaseline/suitable grease to the terminals.


Hopefully, this article has helped you understand what the white stuff on your battery terminals is and how to prevent it from happening. If you found it helpful please share with others who may be experiencing similar issues.

Contact us today if you want to know more!

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