Does a Car Battery Drain Faster in Cold?

Naomi O'Colman

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Does a Car Battery Drain Faster in Cold?

Does a Car Battery Drain Faster in Cold?

Winter can be tough on your car batteries; battery fluid might freeze, the engine will be tough to start, and your car’s battery will likely drain faster. In frigid weather, even the most costly fully charged battery will not be able to work at its optimum. But this begs the question: does a car battery drain faster in cold?

In a nutshell, batteries “drain” faster in the cold because:

  • Engine oil thickens, making it much harder to start the engine.
  • Due to slower chemical reactions, capacity and effectiveness are reduced.
  • In the winter, more electronics are utilized, putting pressure on the battery.

Does a Car Battery Drain Faster in Cold?

It may come as a shock, but the drain is not the right way to describe what you’re going through with your car. Yes, your battery will deplete during startup because the most demanding use of a battery is cranking, which can increase by 2 times in cold weather.

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Because of the three factors described above, batteries drain faster in the cold. Let’s take a closer look:

Engine oil becomes denser

When it’s chilly outside, engine oil thickens, especially if it’s straight-weight oil that doesn’t have distinct viscosity grades for cold and hot temperatures. This can make it more difficult to start the engine, causing the starter motor to consume more current and consuming even more battery capacity at the initiation.

Chemical reactions that are slower

The battery will not be able to generate enough current to meet the demand if it is cold. To complicate things, your capacity will be reduced as well; this will be particularly painful if the battery was already old and was losing capacity due to aging. When a battery drains, its voltage drops faster than when it is warm, and it continues to drop with lower temperatures, giving the impression that the battery is “draining.” In reality, energy does not go anywhere; it’s just that your car can’t use voltage below a certain point.


The electronics you use in the cold are most likely the thing that “drains” your battery. Because chilly weather and early sunsets need the usage of a heater, headlights, and other such devices more frequently. Your charging system may struggle to keep up unless you have a high-performance alternator. This can be amplified if your automobile battery is already outdated and in need of replacement.

Temperature and battery performance

When a connection is created between a battery’s positive and negative terminals, an electric current is generated. When the terminals are linked, a chemical reaction occurs, generating electrons to supply the battery’s current. Because chemical processes take longer when the ambient temperature is lower, a battery that is operated at a low temp generates less current than one that is used at a higher temperature.

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Cold batteries quickly deplete to the point where they can no longer produce enough current to meet demand. If the battery is re-warmed, it will resume regular operation.

How To Keep Your Battery From Dying In The Winter

Here are some tips that will keep your battery from dying in the winter:

  • Keep in a cool place: Hot batteries don’t hold a charge as effectively as room temperature or cold ones do. It’s a good idea to keep unused batteries in a cool place.
  • Have a backup battery: Cold batteries deplete faster than warm batteries, so keep a warm battery on hand if you’re using a cold one.
  • Use a battery blanket: Simply plug it in, wrap it around your battery, and wake up to a smooth start the next day.
  • Place your vehicle in the garage or out of the wind:  To help protect your battery, park it in a garage overnight. If you don’t have access to a garage, park the car’s front end downwind.
  • Give it a boost: A completely charged battery will not freeze until it reaches -76°F, however, a fully depleted battery may begin to freeze at 32°F.
  • Drive for at least ten minutes: To keep your battery charged, you should drive for at least 10 minutes. When you start your automobile, it uses around 5 to 10% of its capacity, which will not be refilled after a short trip, causing the alternator to fail prematurely.