There are few things worse than discovering your car battery is dead on an ice cold morning. A number of factors can conspire to slowly wear down your car battery during the cold winter months. While the physical properties of your battery are affected by cold weather, you might be surprised to learn that your driving habits play a crucial role in keeping your battery charged.
According to Battery Council International:
When the outside temperature is 80 F, a fully-charged battery has 100 percent of its power available to start the car.
When the temperature drops to 32 F, a fully-charged battery has two-thirds of its power available.
At 0 F, that same fully-charged battery has only 40 percent of its power available to start the vehicle.
Your car's alternator is responsible for charging the battery. For your battery to receive a full charge, it requires current from the alternator for a prolonged period, preferably at a warm temperature. When driving during the cold season, we use the defroster for the windshield, the heater to warm us up, and since the days are shorter, we use our headlights more often. All of these accessories divert current away from the battery, leaving a deficit after each trip.
Most of us spend less time driving during the winter, and the trips we do make tend to be shorter. These short trips do not give the battery time to warm up, making it unable to store much of the charge sent from the alternator.
There are a few things you can do to prevent battery failure during the winter. If you have a garage, keep your car in it at night to protect against the cold. Keep your battery terminals tight to their posts, and free of corrosion. Limit your use of accessories when driving. If your battery struggles to turn over the motor, bring the battery into a warm location and put it on a charger overnight.
It might not be your battery's fault. If you notice your headlights seem to dim and brighten occasionally, your alternator might be on its way out. The only way to be sure is to test it. If, however, your car is slow to start, but everything seems normal once it's running, your battery is the most likely culprit. Change it before you find yourself stranded in a cold parking lot on a winter night.
