Why do car batteries die in the winter?

car battery being tested

How do you keep a car battery from going flat in cold weather?        

Winter 2021 has taught us many things across the country, and one is taking care of the car battery. It can be a distraught time when the car won’t start, regardless of what day or time it is, but winter may be the worse time to realize your car battery is dead. 

A car battery does not like cold weather and the colder the temperature gets, the weaker the car battery will get, even a fully charged battery isn’t at 100% in cold weather. A half-charged battery can freeze at a temperature of ten below zero. So, can you winterize your battery? The following 5 steps are recommended by experts in the far north where winter is longer and colder than it is here in Missouri: .

  • Get your car battery checked: Before winter arrives, almost any auto parts store or repair shop will do a free battery check. This takes less than 30 minutes of your time, which is a lot less than when your car battery completely dies and you’re late for work waiting on a tow truck.
  • Drive daily for minimum 10 minutes: One way to prevent car battery problems is to drive the car every day, no less than 10 minutes. This will keep the cold temperature at bay as the engine warms up.  
  • Park your car inside: Parking your car inside the garage will protect it from the direct wind and freezing temperature. Where can you park to help protect your car battery? 
    • In a garage
    • In a parking garage with constant traffic
    • Close to heated equipment
    • Close to a warm building
    • Indirect sunlight
    • Any place that is warmer than in the shade or directs outdoors
  • Wrap a blanket around the car battery: The plastic case around a car battery provides some thermal protection along with the internal design and the material structure. Believe it or not, there are electric blankets specifically for a car battery. These corrosion-resistant heat blankets can be a lifesaver for any car battery and are available in stores and online. 
  • Charge with bigger than a trickle charger: It is essential to keep your car charged,” but when the temperatures are below zero, a trickle charger isn’t going to be enough. Can you leave a trickle charger on all winter?

There are trickle chargers that can be left on indefinitely, typically on a car that is stored. So, yes, you can leave a trickle charger on all winter, that is what they are for, if the car battery is in storage. It is recommended to check on the car battery and charger daily to make sure nothing is getting too hot. 

How do you warm up a car battery in cold weather?

Freezing cold weather is not good on a car battery, so preparing for winter before it arrives is always best for your home and your car. When the cold weather arrives though, what is the best process for the car battery when you start your car in the cold? 

  • Minimize the electrical drain: Ideally, when you park your car, make sure everything is turned off like the headlights, blower motor, radio, etc., and make sure all the doors are closed. 
  • Turn the key and hold for 10 seconds: After 10 seconds if the dashboard lights up, the car battery is charged. If you don’t get any response like lights or sounds, your car battery is not charging and needs a jump or replacement. 
  • Allow the car battery to recover: If the car doesn’t start after twenty seconds of trying, top and wait 2 minutes then try again. If the car battery still isn’t making any contact, it is time to call for a jump. 
  • Check the owner’s manual: Almost every car owner’s manual has a chapter on cold-starting the engine. 
  • For cars 1985 and older: Your car is carbureted so while the car is still parked, push on the gas pedal once and release. That push dispenses gas into the intake and gives the carburetor something to work with, easing the strain on the car battery.  

Is a car battery any good after it freezes?

Maybe, maybe not. You can thaw a frozen battery out and it will probably charge back up. However, it may start your car and it may not, or if it does start your car this time, it may not the next time.  The safest thing to do is get a new car battery installed. Go to a reputable auto parts store or retail store, or use your own mechanic, where you know these are people that know your car battery with fitting for your specific car. 

Mechanic testing failed car battery

How can you tell if your car battery needs replacing?

There are a few symptoms that are an indicator it is time for a new car battery without negative experience of it not starting one morning: 

  • Slow to Crank
  • Check Engine Light
  • Low Battery Fluid
  • Battery Case is Bloated or Swollen
  • Battery is Leaking
  • The Battery Is Older than 3 years 

As with a frozen battery, the same advice holds. Be on the safe side and get a new car battery if your current car battery is exhibiting any of these things. Call (636) 937-0797 today for your car battery jump needs in Festus, MO.