4 Causes Of White Stuff On Car Batteries (& How To Fix It)

If you’ve noticed white stuff on your car battery, then you’re obviously going to be curious as to what it is and whether it’s going to be harmful to the health of your car. In this article, not only will you find out what the white stuff on batteries is, but you’ll also learn what causes it and how to deal with it as well! 

So keep reading to find out everything you need to know!

What Is The White Stuff On Car Batteries?

If you’ve noticed white stuff on your battery, it means that corrosion has started to occur. While this corrosion doesn’t mean you have to change your battery just yet, it is a sign that something is wrong, and you’ll need to treat the issue as soon as possible!

Secondly, as well as noticing white stuff on the car battery, you may also notice it on the terminals, on the tray underneath your battery, and anywhere close to the battery; corrosion can easily spread too.

What Causes White Stuff On Batteries

If you notice white stuff on your batteries, then the most likely causes behind it are:


One common reason that corrosion may be occurring on your battery is due to overcharging. This is normally due to a faulty alternator which is charging your car a little too much. Corrosion caused by overcharging is most commonly seen on the positive terminal of your car’s battery.


Another common reason that your battery may end up corroding is due to overfilling it. When you put too much water into your battery, then you’re going to cause some of the fluid to leak out of the vent, which will once again end up in corrosion and white stuff on your battery.

Hydrogen Gas Leakage

Everytime your battery is being charged, hydrogen gas is created. When this hydrogen gas escapes the battery, it’s going to cause a build-up of white stuff. You’ll often notice white stuff on the negative terminal battery when the battery is being undercharged and corrosion on the positive battery when it’s being overcharged.

Electrolyte Leakage 

If you’re using a lead acid battery, then electrolyte leakage could also be the reason behind a buildup of white stuff. So if you’re using an older car, then electrolyte leakage could be the problem.

Male mechanic charging a car battery

Why Does Your New Battery Have White Stuff On It?

If you have a new battery, you may be wondering why there is a build-up of white stuff. After all, a new battery shouldn’t be corroding so fast. Well, there are actually a number of reasons behind why this is happening.

Connecting A New Battey To Old Terminals

If your old terminals had corrosion on them and you just connected your new battery, then there’s a high chance that the corrosion will begin to spread. 

This is because the corrosion is going to increase the acidic moisture in the engine while the current is being passed through them. 

And if you don’t remove the corrosion and protect your battery terminals with an anti-corrosion compound such as petroleum jelly, then they will continue to corrode until they stop working completely.

A Low Quality Battery

Oftentimes, a low-quality battery will corrode a lot faster than a new high-quality battery because the materials used to make them just aren’t as good. So if you’ve recently bought a battery, but it’s not high quality, this could be the reason corrosion has set in so quickly.

A Bad Alternator

When alternators are undercharging or overcharging your battery, then this will also cause corrosion. You’ll be able to tell if the battery is being overcharged when the white stuff occurs on the positive terminal and being undercharged when the corrosion is on the negative terminal.

Issues During Shipment

If the battery was handled badly during shipment or occasionally during manufacturing, then it can often cause damage that will allow corrosion to set in. 

If you’re not sure whether poor shipment or manufacturing is the cause, check the top of the battery and the battery terminals to see if they’re wet.

Driving On Rough Roads

Driving on rough roads or off-road for too long can also cause battery corrosion to occur on new car batteries. This is because all of the water, mud, and sand end up inside the engine.

Polluted Rain Water

Depending on where you live, acid rain and polluted rainwater could also cause a battery to corrode prematurely. In times of heavy rainfall, the rain can get under the hood of the car and begin to damage the components inside.

What Should You Use To Clean The White Stuff On A Battery?

If you plan on cleaning the white stuff off of your car batteries, then you’ll need the following items:

  • Baking Soda
  • Water
  • A Toothbrush
  • Rags
  • Petroleum Jelly
  • A Socket Wrench 
  • Steel Wool/Wire Brush
  • Gloves & Safety Glasses

How To Clean The White Stuff On Battery Terminals

Now you know what’s causing the white stuff on your battery terminals and what you’re going to need to clean your battery, the next step is to clean your battery so you can continue using it.

So here’s what you’ll need to do!

Disconnect The Battery

Before anything, the first thing you’ll need to do is disconnect the battery. Make sure when you’re doing this, the car is turned off, and you’re wearing your safety equipment. 

To disconnect the battery, use a socket wrench and start with the negative terminal first. (It will be the one labeled with a‘-’, and it will also be black in color.)

Once you’ve done this, you’ll then need to disconnect the positive terminal, which will be red in color and have a ‘+’ on it.

Check The Battery For Damage

Now that your battery has been fully disconnected, you can begin to inspect it for damage. Look for anywhere with white/yellow/blue stuff building up, as all of these colors indicate corrosion. 

You should also check the battery case and make sure that it isn’t cracked or bulging. If you do notice that it has begun to bulge or cracked in places, then you’ll need to replace it. 

Neutralize The Acid

Once you’ve found all the spots that have been damaged by corrosion, it’s time to neutralize the acid. The easiest way to do this is to just use baking soda; however, you can also buy battery cleaner too.

If you plan on using baking soda, just mix two tablespoons with a small amount of water until you’ve created a paste. Once the paste has been created, you just need to use it in combination with a toothbrush to clean the corroded parts. 

You’ll begin to notice that as you place the baking soda paste onto the corroded areas, it will begin to fizz. This reaction is actually the acid being neutralized. 

After you’re done scrubbing the affected areas, you should use a wire brush to give the metal a nice shine and help a clear connection form between the wires and the battery.

Rinse The Battery

Now that the battery acid has been neutralized, you can begin to rinse it and remove the leftover residue. To do this, use a dry rag and start with the terminals and connectors before moving to any other areas of the battery that had white stuff on them.

Once you’ve completely cleaned the battery, you should then rub petroleum jelly on the battery terminals to help slow down corrosion in the future.

Reconnect The Battery

And now all that is left to do is reconnect the battery. However, this time you should connect the positive cable and then connect the negative cable. Make sure you tighten the bolts correctly, and then your car will be good to go again!


Now you know how to deal with white stuff on your car’s battery, here are some more frequently asked questions that people have about battery corrosion!

Is It Safe To Use A Battery That Has White Stuff On It?

If you continue to use a battery that has white stuff on it, then it could result in more permanent damage, not just to your battery but to other areas of the engine as well. So, if you can’t remove the white stuff, you’ll need to replace the battery completely. 

What Happens If You Don’t Deal With Corrosion?

If you don’t deal with corrosion and white stuff on your car’s batteries, then all sorts of things are likely to go wrong with your car’s battery. This can include problems with ignition, the headlights, the AC, and even stalling when you’re driving.

Is The White Stuff That Comes Out Of Batteries Toxic?

The corrosion that comes out of your car’s battery is either going to be lead sulfate, zinc oxide, or anhydrous copper sulfate. Both of these are toxic and should be avoided as much as possible.

In fact, if too much comes into contact with your skin, you may end up with red spots on the areas that have been exposed.

What To Do If You Inhale The White Stuff Of A Battery?

If you inhale the white stuff from a battery, you should go to a medical professional immediately. There are a whole range of sicknesses that can come from inhaling it, so medical attention will definitely be required.

Why Won’t Your Car Battery With White Stuff On It Start?

If you have a car battery with corrosion on it and it won’t start, then it could be because the battery is dead, the alternator is faulty, or the terminals are loose/dirty.

What Causes The Metal Plate Under Your Car’s Battery To Have White Stuff On It?

Oftentimes, when your battery is leaking acid, it may end up dripping down the battery and then underneath it onto the tray. When this happens, the tray will begin to corrode and turn white as well.

What Is The White Stuff On Negative & Positive Battery Terminals?

The white stuff on your negative and positive battery terminals is corrosion. It occurs on the negative terminal when it’s being undercharged and the positive terminal when it’s being overcharged.

Is It Okay To Touch Dry Battery Acid?

You should always avoid touching dry battery acid as it can cause chemical burns to you. While the burns might not show up instantly, you may notice the symptoms beginning to appear after a few minutes. It will start with skin irritation, and then you’ll probably notice the skin turning red or black as well.


As you can see, while it’s not ideal to have white stuff on your battery, it’s definitely fixable, and with the right management, you can get your car battery back to top performance in no time!

If you liked this article, then make sure you check out the rest of the website! Otherwise, have a great day!

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