How to Deal With A Top-Leaking Car Battery

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Car batteries store electricity using a potent corrosive and highly toxic chemical mixture that contains sulfuric acid. For these reasons, a leaking car battery should only be handled with proper protective gear and exceptional caution.

The best course of action is to remove and replace the leaking battery with a fresh one. However, there are a number of steps to follow to ensure you can remove and dispose of the leaking battery safely. Here is a brief guide on how to deal with a top-leaking battery.

Signs of a Car Battery Leaking

Man in Black Jacket and Cargo Pants Standing Beside Red Car

There are many telltale signs of a leaky battery, but they tend to fall into a few common categories.  The following are the most common leak indicators:

1. Cracks

If you see any visible cracks in the battery casing, the battery is already leaking. Check for any fluid that you see near or around the cracks to confirm that the case is compromised.

2. Bubbling

These are typically seen around the cell caps of the battery. The plastic will not be bubbling so much, as there are bubbles of liquid collecting around cell caps. Bubbling liquid usually means the seal or seals on a battery are the source of the leak, and the case may not be cracked or warped yet.

3. Warping/Bulging

Inspect your battery to make sure it’s still retained the shape of its sides. If it’s warped or bulging anywhere, the battery is already leaking or will soon start leaking. The case will crack or the seals will break, and then toxic, corrosive liquid will begin leaking out.

Also Read: Why Do Car Batteries Corrode

Common Causes Of A Leaking Car Battery

Determining the cause of your leaking car battery is an important part of any diagnostic. Sometimes car owners discover their battery is leaking even after they’ve replaced it. It is very important to know what caused the previous battery to leak when that occurs.

To help with that process, here are the most common causes of a leaking car battery:

1. Age

Car batteries are designed to last for a long time but they don’t last forever. On average, most car batteries last about three to five years. However, there are a number of factors that affect how long it lasts.

Fundamentally, leaking is often a sign your battery is worn out and needs replacement. If you see a leak, your battery is not long for this world.

2. Overcharging

Using a battery charger that doesn’t have a “smart charging” feature can cause your battery to continue charging after it’s full. When the battery overcharges, the liquid inside begins to expand, causing broken seals and cracked casings.

It is rare for a battery to overcharge with modern charging technology, but there is always the possibility that the charger could malfunction. A leak on a newer battery can be a good indicator of overcharging.

3. Extreme Weather

When the temperature drops low enough, the liquid contents of your car battery can freeze. As it does, it will expand and cause the case to bulge. This can damage the seals and even crack the top or sides of the case.

Next stop: leaking car battery. This particular problem only occurs in freezing climates, but it can cause leaks even in temperate climates during a cold snap.

So far, you’ve identified a leak, possibly found the cause, and know your battery needs to be removed and disposed of safely. Let’s discuss some tips on safety and safe recycling/disposal.

Also Read: Car Battery Voltage Too High

Step By Step Guide On What To Do With A Leaking Car Battery

If possible, it’s always best to have a trusted auto repair technician remove a leaking battery and replace it with a new one. When that isn’t an option, you should know how to remove the old battery, install the new one and safely dispose of the leaking battery. Here are the steps to take:

  1. Find a maintenance manual or directions for your make and model vehicle. Look for the section on batteries and watch the videos/look at the diagrams for how to safely remove your car battery.
  2. Use protective work gloves to lift the battery out once you have followed the safe removal directions for your car.
  3. Keep the battery level (it can leak or spill) and set it down on a catch pan or some other material that can handle the corrosive battery contents. 
  4. Use your maintenance manual to install the new car battery.
  5. Take the leaking battery to a local recycling center or auto shop. There may be a fee at some auto shops for recycling services.

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All in all, a top leaking car battery is easy to identify, find the cause, remove and replace by yourself. That being said, it is never a bad idea to let professionals handle any repair or replacement that involves highly toxic and corrosive materials. That’s best for everyone involved and well worth the minor additional cost.

Do you have more questions about your car? Check out our other posts below:

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