How temperature effects your battery.

The primary function of the modern automotive battery is well known. But because these types of batteries are often hidden in fixed positions, they regularly get forgotten about and neglected. However, like most things in a car, batteries still require proper installation and maintenance to ensure that it continues to perform its vital function, and the life of the battery is maximised.

One vital variable that is often overlooked when installing and maintaining a battery is the ambient temperature of its location. This is an important variable because the temperature has a significant effect on the chemical reactions that are occurring in the battery. And although it might be a suitable temperature at the time of installation, foresight and management of extreme heat and cold can help prevent stress on the battery.

Many people believe that cold weather is what kills a battery but what is often disregarded is the effect that heat can have on a battery. In fact, it is heat that can cause the most damage to batteries, it isn’t until it becomes cold that the effects of that damage are evident.

In cars, this is becoming more prevalent due to the usable space in an engine bay continuing to be compacted to make way for more complex systems. This reduction in space reduces airflow and on hot days greatly accelerates the chemical reaction. This causes advanced Positive grid Corrosion of the internal cells, creating greater internal resistance, essentially reduces the design battery’s life.

It is important to note that Positive Grid Corrosion is a natural part of the battery’s life and is factored into the design life of the battery. It is only when left in extreme heat that this accelerated. In fact, batteries that are left in ambient temperature over 40oC can reduce its life by up to 50%.

So why do batteries fail in the winter? If we remember Positive Grid Corrosion creates greater internal resistance. In winter, the liquids in a battery become thicker, which creates a slower chemical reaction, with additional resistance, it makes it even more difficult for power to be delivered. Similar to heat when it gets hotter, as it gets colder, the reaction becomes less, at 10oC the reaction is slowed down by 50%, and at 0oC it is 25%.

So although the battery seems to be performing perfectly in the summer heat, it isn’t until winter that the damage becomes symptomatic. Think of it as an injury you sustained when you were young. It is fine through your prime years, but as you get older, it is begins to resurface and become a problem.

To avoid damaging your battery in the summer, keep your car shaded as much as possible and ensure that you have a suitable and high-quality battery. Premium batteries, especially those with warranties of more than 3 years, go through a more stringent quality control process that selects only the purest materials to be included in the product. These batteries are more resistant and designed to withstand heat.

Unfortunately, if damage has been done to the battery, it can be challenging to overcome the problems indefinitely. However, you can help the battery by ensuring in winter the battery is protected from the elements as much as possible and that its CCA rating matches or exceeds that of the manufacturers recommended CCA rating. In addition, it is essential to get your battery before tested before winter to evaluate whether it will be able to perform during winter.

ABIA thank Sealed Performance Batteries (SPB) an ABIA Member company for this article.

Find Your Local Supplier


Australian Battery Industry Association

Contact Us

ABN: 20 050 106 806

Frequently Asked Questions