Why Does My Car Battery Die in Winter?

There is absolutely nothing worse than climbing into a cold, frozen car and discovering that the battery has died. For many people who have had the inconvenience of having this happen, it seems to be much more common in winter. There is a good reason as to why your car battery is more likely to die in winter.

To understand why this happens, a basic knowledge of car batteries is required. First, car batteries are made up of a plastic case that houses several leaf plates which are submerged in a mixture of water and sulfuric acid. A 12 volt car battery has six pairs of lead plates, each producing 2.1 volts.

When this battery is charged, it is able to hold this charge through a chemical reaction between the electrolyte solution (water and sulfuric acid) and lead plates. Over time, this reaction causes lead sulfate to build up on the lead plates, reducing the batteries ability to hold a full charge.

Heat and cold are bad for lead batteries. In the summertime heat, the reaction between lead and sulfuric acid which produces the lead surface increases due to the water in the electrolyte solution evaporating, making the sulfuric acid more concentrated. As winter arrives and freezing temperatures come, an already stressed battery is now further depleted, as cold temperatures slow the batteries chemical reactions. This often leads to a battery failing to have the voltage required to start your vehicle.

As part of regular automotive maintenance, a cars battery can be tested to determine what charge it is able to hold. This gives an indication of the likelihood of a battery failing, and not producing the voltage required to start your vehicle. Often the best option is to replace the failing battery with a new one.

Gary’s Automotive is able to provide battery service, as well as other auto repair. Come have your battery tested, to make sure it serves you well this Winter.