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Show your car battery a little summer loving by charging when it’s hot

21 August 2025

It’s summer, it’s hot, it’s not a season when you have to worry about your car battery. Not like in the cold winter. Right?

Wrong! It might sound strange, but in reality, winters are kinder to your car battery than summers. Hotter temperatures actually wear out your battery more quickly. A hot battery has a higher rate of chemical reactions, quicker evaporation of electrolyte and faster internal corrosion.

A battery works by using chemical reactions to create and store energy. In cold weather, these reactions slow down, which helps the battery last longer by reducing energy loss and wear.

A battery at 27°C will discharge an extra 33% faster than a battery at 18°C. If your car is idle for a few weeks, the losses mount up and the risk of a non-starter increases, potentially building towards a completely failed battery and a costly new replacement.

A major battery supplier in the USA found an average battery life expectancy of 51 months in the cold northern states such as Montana, Minnesota and Maine. In the hot southern states such as Florida, Texas and Louisiana that average battery life expectancy is just 30 months.

Summer brings other demands onto car batteries too. There’s the added load from air conditioning. And there’s the high stakes big summer road trips to think about. Nobody wants their vacation to come to a halt either at home before setting off or by being stranded far away with a flat battery.

The good news is that help is at hand. A little preparation goes a long way and that’s why we recommend regularly connecting your car battery to a charger, even when you think that you don’t need to.

When you connect a CTEK charger such as the CS ONE, it automatically checks your battery and gives it a smart top-up if needed. It also features temperature compensation that adjusts the charging based on the surrounding temperature. In hotter weather the charger lowers the voltage to stop the battery from overheating or releasing gas, helping to protect its health and extend its life.

And for those trips away from home, however far you are going, take a portable booster with you. CTEK’s CS FREE is a portable adaptive booster that can start a dead battery in only 15 minutes. And it can charge up your phone, tablet or laptop too.

And as the longer days, sunshine and long road trips draw to a close, and autumn and winter come into view the more you looked after your car battery in the summer then the more your battery is prepared for the different challenges of colder weather.

Keep your cool this summer by keeping your car battery conditioned and charged with a little regular and simple TLC from your CTEK charger.

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