Your Frozen Car Battery Questions Answered

Learn about why car batteries freeze and how to prevent them from doing it in the future.

It’s bad enough when your car or truck doesn’t start. But when you discover your battery is frozen solid—now that’s brutal. 

When your battery freezes, you’ll usually need to replace it. And a frozen battery is not covered under the manufacturer’s warranty.

Car batteries contain a mixture of sulfuric acid and distilled water. When this liquid inside the battery freezes, it can break the electrical connections inside and bend the lead plates.

This lowers the battery’s output, often far enough that it is useless.

Blain’s Farm & Fleet is here to answer any questions you may have about dealing with a frozen car battery.

What causes a frozen battery?

When your battery gets low on charge, it can freeze. Your battery can get low on charge for a number of reasons.

You could have a draw or short in your electrical system that’s draining your battery. Your alternator might not be working right and not keeping it charged. Or your battery could just be old and not holding a charge as well as it used to.

No matter what the reason, low voltage is bad news if there’s cold weather.

The reference chart below shows how a battery is more likely to freeze when it’s low on charge and at a certain freezing point.

Will my frozen battery still work after I thaw it out?

Probably not. If it does, it will be weaker, and it won’t last long. A frozen battery can be thawed and charged back up, but this won’t always work.

It’s best to replace a battery that’s been frozen. You risk the battery dying and leaving you stranded if you try to use it again.

Safe is much better than sorry with batteries.

How can I avoid a frozen battery?

Check your battery

One way to avoid a frozen battery is to check it often. You might need to charge your battery once in a while.

If you do find that it could use a charge, your local Blain’s Farm & Fleet has a wide selection of battery chargers. Learn how to find the right one on our blog.

Have a professional help

Also, make sure you have your electrical systems checked by a professional automotive technician at least twice per year.

This will help prevent a bad alternator or a short or draw from causing your battery to die. Get your systems checked once before winter and once in the spring.

Replace your battery regularly

The final way to avoid getting stuck with a frozen battery is to replace it every five years.

Blain’s Farm & Fleet offers battery installation service in our Automotive Service Centers. We are happy to help you take the best care of your car or truck.

For more tips on caring for you vehicle, visit our Automotive Blog.