Informational Guide

Car Battery Leaking? (Why & How To Stop It)

In this guide, we help you understand why there is fluid leaking from your car battery and how to stop it.

The last thing you want to deal with is having a car battery leaking. If you have a car battery leaking fluid, you want to act fast. In this guide, we help you understand why there is fluid leaking from the car battery and how to stop a car battery from leaking acid.

Can a car battery leak fluids? Yes, you could notice a car battery acid leak or be asking yourself, "Why is my car battery leaking water?" A car battery contains a mixture of acid and water. In most cases, you will see battery acid leaking from the car battery. 

However, in cold conditions, the water can separate from the acid and leak.

Car Battery Leaking

Why Does Your Car Battery Leak? (Causes Explained)

Why does my car battery leak acid? In some cases, there are cracks or damage to the battery case, causing fluid to seep out. Additionally, if the car battery is leaking from the top, it could mean that the caps to the cells aren't properly sealed.

As the battery ages, it will naturally start to warp or show signs of damage. The older it gets, the more likely it is to fail or cause problems.

As we further examine what causes a car battery to leak, you must factor in overcharging. With a smart charger, the equipment shuts off when the battery is full, thereby preventing this condition from occurring.

My car battery is leaking – now what? If you are living in an extremely cold climate, this could be the problem. The acid inside the battery can freeze, causing the box to expand and push out additional pressure. This condition is similar to what you see with water pipes in extreme conditions.

How To Tell If Your Car Battery Is Leaking? (Common Signs)

What does a leaking car battery look like? We review some tell-tale symptoms of a leaking car battery.

  • Bubbles Coming From Terminal Post 
    The battery acid is looking for a place to escape, so it starts to come out of the terminal posts. If you have a car battery smoking and leaking, it could be due to fluid coming from the terminals.
  • Battery Case Is Damaged 
    A visual inspection of the battery case will help you determine if it is leaking. If the case looks warped, bloated or swollen, fluid could be leaking from it.
  • Battery Corrosion 
    When acid leaks from the battery, it causes corrosion. This condition is most often seen around the terminal caps.
  • Rotten Egg Smell 
    The leaking lead battery produces hydrogen sulfide gas, which often resembles rotten eggs. Some people also claim it smells like sewer water.
  • Sweating 
    The battery could vent the hydrogen sulfide gas when there is a lot of pressure put on it. This reaction leads to condensation on the outside of the case.
  • Low Battery Fluid Level 
    If the fluid is leaking from the battery, you will likely notice lower levels as it escapes. If you are continuously filling the battery up with distilled water, there might be a leak somewhere.
Car Battery Leaking From Top

How To Stop Car Batteries From Leaking?

If you don't want to deal with a leaking car battery, you need to take care of it. For starters, purchase the right battery for your vehicle. For example, if you live in an area with harsh winters, you want the best car battery for cold weather.

Additionally, you don't want to overcharge the car battery. Not only do you want to have the best battery charger hooked up, but you should know how long it takes to charge a car battery.

On top of that, you should keep the battery clean and free of corrosion. Learning how to clean battery corrosion is a simple task that only requires some basic equipment.

We recommend inspecting your car batteries often. If you notice anything wrong with the case or there is leakage, you should replace the battery with a new one. Typically, a good car battery will last between three and five years.

Disposing Of An Acid Leaking Car Battery Properly

Once you see trouble, you want to understand proper leaking car battery disposal. It's simply not safe for the environment to put your used car batteries in the trash. Instead, the battery core must be taken to an authorized recycling center for reuse.

Thankfully, you can see your used car battery in many locations. Who buys used car batteries? Most auto parts stores, as well as local repair shops, will pay you a few dollars for the battery core.

Additionally, you can work directly with a recycling center in your area to cut out the middleman. Always use care when handling your car battery, as the acid can cause skin irritation.

People Also Ask (FAQs)

Is it safe to drive with a leaking battery?

If a car battery leaks, is it dangerous? Yes, you should never drive with a leaking battery because the sulfuric acid is dangerous to you, the environment, and your car.

Can a leaking car battery explode?

Yes, if the flammable acid is leaking near an ignition source, it could explode. While this doesn't happen often, you should never underestimate the danger of a leaking car battery.

Can you jump start a leaking battery?

You should never attempt to jump start or charge a leaking battery. It is unstable and could explode. Instead, replace the car battery to remain safe.

Can leaking batteries damage a car's engine?

Because the sulfuric acid is leaking, other components nearby could become damaged. The acid could create corrosion or oxidation on the engine parts. Avoid costly repairs by replacing the leaking battery immediately.


Is a leaking car battery dangerous or is this normal? It's never normal to see fluid leaking from your car battery. Replace it immediately and keep yourself safe from harm.