Why is my car battery leaking & What to do about that?

Updated Mar 12, 2021 | Same topic: Handy Maintenance Tips

A common problem for old batteries.

A car battery is one of the important components in your car as it supplies energy to various electrical components such as lights, an infotainment system, and more. It is also used to start your engine by supplying power to the starter motor that cranks the engine.

As time passes by, you might encounter that your car battery is leaking. If your car battery is leaking or damaged, then you should take care of it immediately as it is essential in keeping your car running. Without a working car battery, you won’t be able to start your engine at all.

With that being said, we have provided some symptoms that you can consider to determine whether your car battery is leaking or not. We have also listed down some of its causes so you can try to avoid it next time around and what you should do when this condition occurs.

Car battery corrosion

Leaking batteries will form corrosion around your car battery's terminals

3 Symptoms of car battery leaking fluid

1. Rotten Egg Smell

You most likely know what the smell of a rotten egg is like. As such, you can use that to determine whether your car battery is leaking. A good battery shouldn’t produce any smell considering it contains dangerous acids. However, a car’s exhaust system can also produce a rotten egg smell when sulfur is combusted in the cylinders. So if you smell a rotten egg, it’s your call to tell whether the smell is coming from your battery or someone else’s exhaust. As a precaution, consult your trusted mechanic.

2. Corrosion around terminal caps

Corrosions around your car battery’s terminal caps are strong indicators that it is leaking acid. It looks like a white foam with shades of green and rusts around it. Try to stay away from those corrosions as acids that leaked from your car battery are dangerous and cause serious health issues.

3. Low battery fluid

One of the basic maintenance services you can do to your car battery is to refill it with electrolyte fluids. In doing so, you will extend the life of your car battery which will help you refrain from buying a new one. If your car battery is often low, then it means that the fluids are leaking which is something you want to avoid.

Car battery corrosion

If you see this, you need to get your battery checked

>>> Related: Dispose of your car fluids properly

What causes car batteries to leak?

Cause #1: Age

Car battery manufacturers dictate a specific shelf life for their products to tell consumers when to replace their batteries. Once you go past the shelf life of your battery, then it will not function like a new one and will start leaking acids which can be dangerous.

On average, car batteries can last for around three to five years, or around 60,000 km to 100,000 km. Some batteries might need to be changed earlier especially if you drive a lot and have installed more accessories that need electrical power. As such, follow the specified shelf life from the manufacturer to avoid leakage.

Cause #2: Overcharging

You can extend the life of your car battery by charging it. However, overcharging can cause more serious damage which will cause you to buy a new one. If you leave your battery charging for a long time even at low amperage, it can cause gases to buildup which will result in leakage.

Charging your car battery will usually take around four to 24 hours, depending on the amperage you configured on your car battery charger. Going past the said times will result in overcharging which is something we would like to avoid. If you are unfamiliar with charging your batteries, you can visit your local auto shop and they will do it for you.

Cause #3: Battery Cracks

There are various reasons why a car battery cracks. Some of which include excessive shaking from driving through rough roads. This is why it is recommended that you go slow when driving through uneven roads especially if your car has a bad suspension.

Another common reason is extreme temperature. Both extreme cold and hot weather can damage your battery resulting in cracks. Your car battery fluids can freeze in cold weather which causes expansion. Meanwhile, your car battery parts can expand in hot weather. As such, you should store your car in a well-conditioned parking space.

Car battery corrosion

Try not to run your car with a leaking battery

What to do when a battery leaks

There are two things you can do when your car battery leaks. You can either clean it or replace it with a new one. If you decide to clean it, you will need a mixture of water and baking soda, a terminal cleaner, a battery protector, gloves, and goggles for safety reasons.

Brushing a car battery terminal

Any type of car battery cleaner will do

Pour in your mixture to the terminal sides and let it sit for at least 30 seconds. You should hear a fizzing sound which means that the mixture is working. Rinse the mixture with water and remove the terminals starting with the negative side to avoid a short. Brush off the terminals using the terminal cleaner.

Before connecting the terminals, clean the battery off with any clothing. Again, connect the negative terminal last for safety measures. If your car battery leaks again and causes corrosion for the second time, we recommend you replace the battery to prevent more damage from occurring.

Cleaning a car battery

Always keep your battery clean to avoid unwanted buildups

>>> Related: Battery terminal: How to clean & Replacement cost

FAQs about car battery leaking

Q: Is it safe to drive with a leaking battery?

No, leaking acids from the battery are harmful to you, the car, and the environment.

Q: How long should I charge my battery?

You should charge your car battery for around four to 24 hours, depending on the amperage.

Q: How much is a car battery in the Philippines?

Prices can vary from Php 3,000 to Php 7,000, depending on the battery.

Q: How long do car batteries last?

On average, car batteries will last for around three to five years, depending on how much the battery is used.

Q: What happens if I make contact with battery acid?

Making contact with battery acid will irritate your skin. If it reached your eyes, you can go blind from it.

Here at Philkotse.com, we value your interest in the automotive industry. Visit our website to find out more.

Rex Sanchez

Rex Sanchez


Rex Sanchez grew up in Saudi Arabia where he saw and got into the automotive scene. He started his career for an aviation company in the said region, writing about turbines and rotors which are later distributed for educational purposes. And now, he joined Philkotse.com as a staff writer. Currently, he is the youngest on the team and is more than ready to grow in the field.

Facebook: https://www.facebook.com/rexsanchez09

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