It’s bad enough when your car or truck doesn’t start, but when you find out your battery is frozen solid, now that’s brutal. When your battery freezes, it usually needs to be replaced. Also a frozen battery is not covered under the manufacturer’s warranty. When the liquid inside the battery freezes, it can break the electrical connections inside and bend the plates. This lowers the battery’s output, often far enough that the battery is useless.
What Causes a Frozen Battery?
When your battery gets low on charge, it can freeze. Whether you have a draw or short in your electrical system that’s draining your battery, your alternator isn’t working right and keeping it charged, or if your battery is just old and not holding a charge as well as it used to, low voltage is bad news if it’s cold outside.
The reference chart below shows how a battery is more likely to freeze when it’s low on charge.
|% of Full Charge||12-volt Battery Voltage||6-Volt Battery Voltage||Freezing Point|
|100%||12.78 V||6.39 V||-92.0 °F|
|92%||12.66 V||6.33 V||-71.3 °F|
|85%||12.57 V||6.28 V||-62.0 °F|
|62%||12.27 V||6.13 V||-16.0 °F|
|40%||11.97 V||5.98 V||+5.0 °F|
|20%||11.67 V||5.84 V||+19.0 °F|
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 to Avoid a Frozen Battery
One way to avoid a frozen battery is to check your battery often. If you do find that it could use a charge, your local Blain’s Farm & Fleet has a wide selection of battery chargers, and our Automotive Blog will help you find the right one.
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.
The final way to avoid getting stuck with a frozen battery is to replace your battery 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.