Why car batteries die in cold weather

If you’ve experienced that sinking feeling of turning your key in the ignition only for nothing to happen, you won’t be surprised to learn that flat batteries are one of the main reasons for car breakdown calls in the UK - and this problem is particularly common when cold weather strikes. But have you ever wondered why your car sometimes seems more reluctant to start on cold days?

In this blog, we look at why falling temperatures impact on your vehicle’s battery - and the steps you can take to ensure you’re not caught out this chilly season.

The effect of cold weather

The majority of car batteries hold their charge using a liquid electrolyte solution - and this solution is affected by temperature. Although it takes extremely low temperatures to cause the battery to freeze, cold conditions can reduce the electrolyte solution’s ability to transfer full power. This is why you’re more likely to have trouble starting your car when temperatures tumble.

The way you use your car during cold weather can also impact on the battery. For example, because of the bad weather and shorter days, people tend to use their lights more at this time of year, as well as other systems that drain power such as heaters and windscreen wipers and washers. All of this puts added strain on your vehicle’s battery.

Cars also tend to be used less during spells of icy weather and over the Christmas holiday period when many people are off work. Because batteries gradually lose their charge when they’re not being used, this can make them more prone to fail.

Signs that you have a flat battery

So, how do you know if your car has a flat battery? If you don’t hear anything when you turn the ignition key, or you notice a faint whining noise but the starter motor doesn’t kick in, the chances are you have a flat battery. There are other warning signs too. For example, the ignition lights on your dashboard may not come on, or you might not be able to unlock your vehicle via remote central locking.

It’s important to be aware that there are other problems that cause similar effects, such as a faulty alternator or starter motor. If you have a relatively new battery and it keeps going flat, the alternator is probably to blame. Flickering dashboard lights also point to this issue. Meanwhile, a sign that your starter motor has gone is a clicking sound when you turn the key in the ignition.

If you’re not sure what’s causing the problem, you’ll need to arrange to have your car checked over by a technician.

How to fix a flat

Flat batteries always seem to happen at the worst possible times. If you’re in a rush to get somewhere and you discover that your car’s not cooperating, you may be able to jump start it. However, to do this you’ll need access to another vehicle and some jump cables.

For a more long-term solution if your battery is old or damaged, you may benefit from investing in a new one. We offer a full car battery replacement service. You can purchase a battery online and book an appointment to have it fitted at your local Kwik Fit centre.

Steps to protect your battery during cold weather

Fortunately, there are steps you can take to protect your car battery when cold weather strikes. For example, if you have access to a garage, make sure you park your vehicle in it to shield it from the weather.

If you use your car to make short trips on a regular basis, it’s generally a good idea to charge your battery at least once a week during cold snaps. This is especially important if the battery is over three years old.

To conserve battery power, make sure you switch all power loads off before you turn your engine off at the end of a journey. This includes your lights, wiper blades, radio and heater. Also, before journeys, ensure that all these things are switched off before you turn your ignition on. In general, try to avoid using heaters, heated screens and heated seats when you don’t need to. Bear in mind that some in-car sat navs and MP3 and DVD players can drain your battery if you fail to disconnect them, so this is another thing to pay attention to. It’s also important to make sure that you don’t leave any interior lights on in your car. This includes in the boot.

In case the worst should happen and you do get a flat, you may want to consider investing in a car battery booster. This is a rechargeable device that you can clip onto your battery to get it working again. This handy piece of kit doesn’t require you to use jump leads and it works more quickly than a conventional car battery charger.

Make sure you get your battery checked on a regular basis too, especially if it’s over three years old. As they age, batteries tend to become weaker and they can be particularly badly affected by the cold. If you notice that your battery isn’t holding its charge effectively, it’s probably time to get a new one.

By understanding why your battery is more likely to fail in the cold and taking steps to prevent this, you should be able to avoid getting an inconvenient flat. If you’re concerned about the charging capability of your vehicle’s battery, don’t leave it until your car won’t start. Call into your nearest Kwik Fit centre instead and our experts will carry out a free check.