All you need to know about car batteries

Bradley Jando | Thursday 2nd September 2021 12:06pm

Car Battery with Jump Start Leads Connected to Terminals

Your car battery is the lifeforce of your vehicle. Itís what powers your car and keeps it moving, which means the last thing that you want is for your battery to die - and for you to be left stranded.

By being well acquainted with your car battery and how it works, you can give it the care and support that it needs - helping to make sure that your car wonít break down when you need it most. Here are some things that you need to know about your car battery that will help you in the long run.

How car batteries work

So, you know that your car battery is what powers the engine, but itís not as simple as it sounds. While youíre turning the key in your car to start the engine, your car battery is converting chemical energy into electrical energy, which is how your car delivers the power needed to keep everything running. Your battery not only provides the energy that your car needs to start, but it also stabilises the voltage to ensure that your engine keeps running.

This important part of your car typically lasts between 3 to 5 years, but this can depend on exposure to certain environments, as well as your driving habits. But having an ill-performing car battery can ultimately harm your carís charging system or starter. When you have a weaker battery, it tends to rely on other parts of your car, putting potential stress on the charging system, starter motor or starter solenoid.

This can lead these parts to break down, as additional voltage goes through them to make up for the lack of power from your car battery. This can result in needing to replace these components with little to no prior warning. By ensuring that you have regular battery checks, you can help to prevent any unnecessary damage to these parts of your car.

How do I know that I need a car battery replacement?

If youíre trying to figure out when you might need a new car battery, there are a variety of signs to look out for - but here are some of the most common symptoms that you might be able to spot if your battery is starting to die.

The engine is taking longer to start

If it takes your engine longer than usual to start, and this is starting to become a frequent occurrence, it might be worth checking out your battery. If the components inside your car battery are wearing out, it will take longer for it to create a charge for the starter.

Start-stop not functioning

Vehicles with start-stop systems that temporarily turn the engine off when coming to a stop and then restarting again when the accelerator is pressed, rely heavily on the car battery. If you notice that your vehicle isn't switching off and restarting automatically like it used to, this could be a tell tale sign that the battery is starting to struggle and may need replacing.

A bad smell

If thereís a bad, rotten egg type smell that appears when you open the hood of your car, it might be that your battery has experienced some damage or that it might be leaking gas. If this occurs, itís crucial that you get your car checked as soon as possible and get it replaced if needed.

The check engine light is on

While some of us might ignore the check engine light when it appears on our dashboard, one of the many things that it is designed to tell us about might be that your battery is running out of power. 

Alternatively, if your check engine light is flickering on and off it might be that your battery isnít receiving enough electricity. If you spot either of these indicators, you should take your car to be checked.

Dim lights

Your car battery doesnít just power the engine, but itís also responsible for your carís electronics, including lights, radio and your dashboard computer amongst others. If youíre noticing that the electronics in your car are struggling to run at their best performance, it might be that your battery is losing its charge and canít power all of these things at once.

The battery case has changed shape

Your battery case can become misshapen when it is exposed to extreme environments, including high heats and very low cold temperatures. This can impact the lifespan of your battery as the case will swell and crack. If itís not its typical rectangle shape, itís likely that it isnít working properly.

Corrosion on your connectors

Nowadays, cars use sealed batteries and are maintenance free so this is unlikely to occur, but if you notice that the metal parts of your battery are covered with a white ashy substance, your battery has a corrosion issue. If the terminals, which are the positive and negative connections at the very top of your battery, have been corroded, itís likely you will have trouble starting your car due to voltage problems.

Your battery is old

If you canít remember the last time your battery was replaced, chances are that youíve had it for a while. Donít forget that for the best performance, you need to ensure that your battery is checked every 3 years as they typically only last between 3 -5 years!

Kwik Fit Car Battery Services

Here at Kwik Fit, we offer a variety of services to ensure that your car battery is in the best condition possible at all times. Whether you need a car battery fitting, car battery replacement or simply a free car battery check, you can get in touch by visiting your local Kwik Fit centre - or you can book online.

Any facts, figures and prices shown in our blog articles are correct at time of publication.

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