Does the Cold Weather Kill Your Car Battery?

During the colder months, more and more drivers find themselves facing a vehicle that simply will not start. Is the cold weather to blame? The answer is more complicated than it may seem especially for drivers in the south. Learn more about cold weather’s impact on your car battery here.

How Do Car Batteries Work?

Car batteries are cells that store chemical energy and turn it into electrical energy when needed. They rely on a lead-acid chemical reaction that ignites a short burst of energy that turns on your lights, accessories, and engine. Once the car is moving, the energy supplied to the engine comes from the alternator.

Car batteries are charged by the movement of your car driving; if they’re dead, they can also be jump-started by a different car. However, once a battery stops holding a charge within its cells, it’s time to get a new one.

Most car batteries have a lifespan of three to five years, but this can be shortened by extreme weather conditions. If you live somewhere with extreme temperatures, you might have to replace your battery every year.

Why Winter Is Hard on Car Batteries

So, does cold weather kill your car battery? Yes and no. Cold temperatures put severe stress on your battery, which is why the winter season is often a catalyst for car battery replacements. The cold weather has your vehicle facing two challenges at once: power loss with slow chemical reactions and oil/engine troubles.

In the winter, car batteries are forced to work harder to get your engine going. Cold temperatures thicken your engine’s oil, which makes it move more slowly. This increases the amount of power needed by your battery to kickstart important processes. If the amount of charge in your battery is already reduced by the cold weather, you may find yourself with a vehicle that’s unable to start.

In addition, cold temperatures affect the chemical reaction that takes place inside the battery when you turn your car on. The cold makes your battery more sluggish, and it requires more time to successfully ignite.

Finally, the amount of technology you have in your car can take a big toll on the battery’s ability to do its job. Seat warmers, headlights, radio, and electronic device chargers all demand power from the battery to start. This can be overwhelming and cause the battery to fail, especially if it’s older and already struggling to hold a charge.

Since your car’s battery is already working at a disadvantage during the winter months, you won’t be surprised to learn about the things that will almost guarantee your car’s battery dies when it’s a cold morning and you’re trying to hit the road. Here are the top reasons why batteries die and how to prevent them.

dead battery cold weather

Power Loss and Slow Chemical Reactions

Freezing weather drains your battery power by 30-60%. Your battery naturally recharges as you drive—but you must first face the challenge of getting it started. Why does the cold drain battery power?

Most batteries work through an electrochemical reaction, which sends power signals to your terminal ends. This chemical reaction slows down in colder weather, weakening your battery’s power.

Oil and Engine Troubles

In the colder weather, your vehicle’s oil becomes much thicker. Low temperatures also strain internal components, like the radiator, belts, and hoses. Collectively, this slows down your engine causing it to need an extra surge of power to start. Combined with the fact that your battery has less power to offer, this can prevent your engine from turning over.

The Secret to Dead Car Batteries in the Winter

You might find yourself thinking, “It is not too cold why is my battery dying?” This is a common issue for drivers in the south. The freezing winter temperature does put stress on your battery, but this is not often what kills your battery. Ultimately, the true killer of car batteries is the summer’s heat. It causes internal battery corrosion and evaporates the electrolytes that your battery relies on.

Summer damage then leaves your battery unable to fight off the stress of cold weather. For drivers in the south, this means that your car battery faces extensive summer deterioration.

Then, when the weather becomes cold, your battery does not have the structural integrity to manage the added seasonal challenges. If you need help getting to the mechanic for a battery replacement, here is our guide to helping your vehicle start when it is struggling in the cold.

7 Mechanic Tips on Protecting Your Car from the Cold

1. Maintain Your Recommended Oil Change Schedule

Oil changes are essential year-round, but they are especially important during the colder months. The cold weather makes your oil and other engine fluids move more slowly, which requires your vehicle to work harder to operate.

Dirty, contaminated, and depleted engine oil can substantially enhance this stress. Double-check to ensure you are on track with your manufacturer-recommended oil change schedule. If you are close to needing an oil change, it might even be worth getting this service a little early to safeguard your car against wintery weather.

2. Watch Out for Your Battery

While the cold weather does not damage your battery, it can deplete your battery’s charge. Combined with the fact that your vehicle requires an extra surge of power to start due to slow-moving engine oil, battery failure can leave drivers stranded in the winter.

You can prevent battery troubles by ensuring your terminal ends are clean and preserving battery life, when possible. This includes unplugging chargers and turning off your lights when the vehicle is not running. You can also get a battery replacement at the first signs of a dying car battery.

3. Park in the Garage

Naturally, the temperatures get colder after the sun sets making this the most vulnerable time for your vehicle. You can help keep your car protected by parking in an enclosed garage each night.

While most garages are not climate-controlled, they can insulate your car while keeping away the frost—with the added bonus of keeping morning ice off of your windshield. Just be sure to open your overhead garage door before starting your engine to avoid exhaust venting into your home and car.

4. Keep an Eye on Tire Pressure

When the temperatures drop, the air inside your tire compresses. Low tire pressure can lead to a wide range of troubles, including:

  • Decreased fuel efficiency
  • Poor vehicle handling
  • Increased risks of tire sidewall damage
  • Enhanced and uneven tire wear

By ensuring you maintain the recommended pressure (as indicated on your tire information panel), you can help keep your tires protected. You can often even score a free tire pressure refill from a local mechanic shop.

5. Check in on Your Radiator, Belts, and Hoses

One lesser-known risk of cold weather is the damage it can cause to your radiator, belts, and hoses. Radiator fluid is a mixture between antifreeze and water. While antifreeze has an impressive freezing point of -36℉ (hence the name), water has a freezing point of 32℉.

As such, your radiator fluid is susceptible to partial freezing during cold winter nights. This is especially true if your fluid is old, contaminated, or depleted. A radiator fluid flush can help keep your radiator protected. A mechanic will also check its supporting components—including the belts and hoses—for signs of wear.

6. Complete Tire Tread Checks

When the roads accumulate snow and ice, your tires will have to be extra responsive to keep you safe. To keep you and your vehicle protected, you will want to ensure that your tires have at least 2/32 of an inch of tread. You can read our guide to checking tire tread depth here. It is also necessary to keep an eye out for uneven tread wear and signs of rubber rot.

7. Headlight Bulb Checks and Restoration Services

The cold, dark winter days and nights will put your headlights to the test. Double-check to ensure your headlights are bright and functioning properly. You may need a simple bulb replacement if you notice one of your headlights dim or burnt-out.

If your headlights are dim or yellowing, this could be a sign of oxidized lenses. A headlight restoration service can repair this issue to keep you safe on the road during the darkest days of the year.