Car batteries: After the summer heat comes the deadly freeze

• 40 percent of car breakdowns are caused by battery failure
• Heat shortens the life-span of car batteries
• Battery replacement should be carried out by a workshop

When temperatures start drop bringing cold winter weather, it is time to take your car to the workshop and get it ready for the season. While changing tyres, testing lights and refilling fluids are standard procedures, the battery is often overlooked – yet the continuous operation of windshield heaters, rear window defrosters, headlights and wipers puts it under a constant strain. According to the RAC the second most common cause of vehicle breakdown in the United Kingdom is a flat or dead battery, second only to a punctured tyre. The only way to ensure your batter will make it through the winter is to have it professionally checked by a workshop.

Batteries age in summer and fail in winter
Winter’s cold weather often proves too harsh for a weak battery to survive – especially when preceded by an extraordinary long and hot summer as this year was. Heat dramatically shortens the life-span of a battery, so by the time winter comes, older batteries are close to their limit. “Many drivers think that cold weather does damage to the battery, but it is the heat that is the start of its downfall,” explains Dr. Christian Rosenkranz, Vice President Engineering at Johnson Controls Power Solutions. An outside temperature of +20°C is optimal for a car battery. This summer the temperature often climbed over +30°C.

High temperatures lead to self-discharge of the battery and cause its electrochemical parts to age more quickly. “These effects may not cause the battery to fail immediately, but they can jump-start the deterioration,” says Rosenkranz. Whilst this development remains unnoticed throughout summer and autumn, the problems start to show in winter, when more energy is needed to start the engine. For this reason, the battery should be checked regularly throughout the whole year.