Batteries are an investment in both time and money. They are often quite costly for the average person, so ideally, they should last as long as possible. Also, a flat battery at the wrong time could place you in an uncomfortable or dangerous situation.
Whether hot or cold, the temperature can have a significant impact on battery life and battery performance. There are also many safety implications to consider when it comes to temperature.
Before we dive into how temperature affects batteries, we should first establish the basics of what happens inside a battery when it is producing an electrical current.
What happens inside a battery?
A battery converts chemical potential energy to electrical energy. All batteries consist of electrolytes and electrodes (connected to the battery terminals) of differing materials.
An electrolyte is the solution inside the battery.
Depending on the type of battery, it can be a liquid, paste or gel made up of various compounds. Its purpose is to transport positively charged ions between the positive and negative electrodes of the battery and ultimately produce a current.
What happens inside the battery to produce the charge is an electrochemical reaction. Adding heat will speed up the reaction and taking away heat will slow down the reaction. This gives us an indication as to why temperature has such a profound effect on batteries.
The effects of warmer temperatures on batteries
Excessive heat is one of the most common causes of decreased battery life. Because heat speeds up the chemical reaction in the battery, electrical current is also being produced at a faster rate. A short-term increase in battery performance can be observed from this. However, the rate of unwanted chemical reactions will also increase.
This can lead to some damaging effects on the battery’s internal structure, ultimately preventing it from performing as it should.
For a lead-acid battery, the water in the electrolyte solution begins to evaporate much more quickly than it would at a normal operating temperature. Gassing will also occur, where the compounds in the electrolyte will start to convert from liquid to gas. The plates and electrodes will start to corrode, and a film builds up on the electrodes in a process called passivation.
Heat can also warp and bend the internal and external components of the battery, causing it to become structurally unsound. As evaporation and gassing increase, pressure will build up inside the battery. At extreme temperatures, even batteries that are sealed and designed for higher temperatures could leak or explode.
As we can see, at best, prolonged exposure to heat starts to increase the wear and tear on the components of your battery. All of this will ultimately reduce your battery life. At worst, there are serious safety implications to be concerned about.
The effects of colder temperatures on batteries
In colder temperatures, we can expect to see the opposite of what happens to batteries when the weather is hot. Cooler temperatures mean that less heat is going into the chemical reaction inside the battery, so the reactions will occur at a much slower rate.
Because of this, the current that the battery produces will also be reduced (and therefore the capacity of the battery as well). When a battery is chosen, its capacity needs to match the requirements of the motor and the electronics of the vehicle. Unfortunately, during cold weather, the drop in capacity can also mean that the battery no longer meets the requirements of the starter motor.
To make matters worse, motor oil also tends to become thicker (more viscous) in colder weather. This can make it difficult for the engine to turn over, resulting in a need for more than normal current to be drawn to start your vehicle.
Winter driving also tends to put more strain on batteries, as windshield wipers, headlights, and blower fans from car heaters all require a current to operate. These operations increase the amount of current that is drawn from the battery.
When looking at your battery’s specifications, the CCA (Cold Cranking Amps) is the number representing how much current your battery can put out in cold weather. The specifications will also indicate the temperature range to which this number applies. A higher CCA means that your battery is more equipped to handle colder weather. However, even batteries with a high CCA will struggle at very low temperatures.
Older batteries will also struggle more in colder weather, so this is something to bear in mind when heading into the winter months.
The ideal temperatures for batteries
The optimal storage temperature for most batteries is around 25°C to 27°C (around room temperature). However, most batteries have quite a wide operating temperature range.
As a general rule, most quality lead-acid batteries will perform reliably in operating temperatures between -5°C and 50°C These criteria apply to all lead-acid batteries and are valid for conventional, EFB, AGM and GEL technology. Lithium batteries can operate safely between -20°C and 60°C. However, the ideal operating conditions for most batteries will be between 10°C and 30°C.
A crucial point to remember is that heat damage and reduction in performance due to cold weather are not product defects. Rather, they are the result of a battery being used outside of its ideal operating conditions.
If you are ever unsure about whether your battery is being operated or stored at a safe temperature, most battery specifications and operating manuals will have a section on storage and temperature control. Different battery technologies handle heat differently, so it is always important to stay informed on the correct battery maintenance procedure for your battery.
Simple ways to greatly increase the life and performance of your battery:
One of the most important things you can do is to charge your battery regularly. This prevents damage due to sulphation and keeps your battery running optimally. Most battery chargers do not have smart capabilities, meaning that they cannot detect your battery’s state of charge, temperature, and other important conditions.
These chargers will simply charge your battery. However, the other main contributor to decreased battery longevity is overcharging. Ordinary chargers are unable to recognise when the battery has reached the proper capacity, which can cause damage over time.
Battery Power-Zone recommends the range of highly intelligent CTEK chargers, as they are able to detect and respond to your battery’s conditions. You will also be able to monitor your battery’s health and state of charge on the CTEK app, allowing you to take control of your battery maintenance.
In the summer months, there are also some basic preventative measures that can be taken to prevent your engine bay from overheating. This is important because an overheated engine bay will also raise the ambient temperature around your battery.
Periodically checking your engine coolant to make sure that it is topped up will reduce the chances of your engine bay overheating. On hot days, it is always a good idea to park your vehicle in the shade or in undercover parking, when available. Along with that, servicing your car’s cooling system regularly will keep it in tip-top shape.
Topping up your motor oil when necessary is also fundamental, as low oil can cause your engine to overheat.
Additionally, batteries can be insulated against temperature fluctuations. A battery insulation jacket can prevent extreme temperature fluctuations in both hot and cold conditions, taking some of the burdens of controlling your battery’s temperature off you.
It is also important to ensure that unused batteries are stored in a cool, dark place, and to also charge them regularly.
Battery Power-Zone’s general maintenance tips for the longevity of your battery during the colder months
Charging your battery regularly and ensuring that your state of charge is at the ideal point according to your battery’s specifications is one of the simplest ways to reduce the capacity drop seen in colder conditions. A fully charged battery is much less likely to be unable to meet the electrical demands of your vehicle.
Batteries that are not frequently charged are subject to more extreme reactions to a drop in temperature. In fact, batteries with a low state of charge can freeze at a temperature of -1°C. This can lead to the expansion of the water in the battery fluid, causing irreparable damage to the battery cells.
Performing maintenance checks on your battery before going into the winter season will also help you pick up any issues likely to exacerbate cold-weather-related issues, which could prevent an ageing battery from dying due to the cold.
As discussed earlier, insulating your battery with an insulation jacket will also prevent extreme temperature fluctuations.
While all these considerations may seem costly and time-consuming, they are essential in ensuring that you get the most out of your battery. Battery Power-Zone takes the guesswork out of battery maintenance for you with free battery testing, free battery fitments and free call-outs.
With winter fast approaching, you are welcome to browse our contact us page to find your nearest branch. Let us help you keep your battery performing optimally this season.