Why car batteries fail when it freezes (and how to prevent this) – Jalopnik

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The concept of a battery is not new and in fact may be more than a few thousand years old. However, it was a French physicist named Gaston Planté, who in the mid-19th century^e century was the first to incorporate the ingredients still used in many batteries today: sulfuric acid and lead. Standard 12-volt car batteries consist of six cells, each responsible for converting chemical reactions into usable electricity. Simply put, when lead plates in the cells combine with sulfuric acid, ions are released, which produce the power you use to start your vehicle. However, just because many batteries use the same technology does not mean they are all the same. Consumer Reports says these are the best car batteries.

Although generally a very reliable energy source, the chemical processes in a car battery do not work well at low temperatures. This is because cold weather inhibits the reactions in the cells needed to generate electricity. These ions, which need to move to generate electricity, suddenly have trouble navigating a thick chemical sludge in the cells. This causes a reduction in both capacity and power, potentially causing you to get stuck. Fortunately, there are ways to fix this problem, which will reduce the likelihood of starting your car and hearing that dreaded clicking sound from a starter starved for energy.

Another way to combat the chill under the hood, and one of your favorite cold weather car mods, is an engine block heater. There are several options, from blankets and magnetic heating pads to dipstick elements and more advanced inline coolant heaters, depending on your vehicle and budget. Increasing the engine temperature is useful, even if it does not directly affect the battery itself, because a warm engine requires less energy from the battery to start.

Another way to maintain your battery’s performance in the winter is to drive it regularly (especially if you can’t park it in a garage). If you don’t drive for days at a time, the cold can discharge your battery over time. The exact amount depends on many factors, but ultimately, without the ability to recharge over a long drive, there won’t be enough energy to run the engine on those frozen mornings.

Another thing to keep an eye on is the use of accessories, such as devices plugged into your car’s wall socket or aftermarket stereos. These can be useful when charging a smartphone or tablet, for example, but should only be plugged into the socket while driving. In some cases, energy from the battery continues to flow to these accessories after the engine is turned off. While this won’t immediately put a significant strain on your battery, it can take its toll over time, causing your battery to no longer be able to provide enough energy for winter starting.