Your car’s battery is an essential component to keep your vehicle functioning, so when it stops working, you need to know how to fix it. Although flat car batteries are extremely inconvenient, they are surprisingly easy to revive.

Make the most of your car batteries

In general, car batteries have a lifespan of four to six years. Factors which impact the lifespan of your car battery include what type of vehicle you drive, weather conditions and, of course, driving habits. The battery is one of the most important components of your car because if it is not working, your vehicle will not start. There are many prevention methods you can utilise to minimise the chance of your battery failing at an inconvenient time or place. Alternatively, there are many ways you can revive your batteries if they do stop functioning.


There are several factors which can indicate you may need a new battery. Regularly checking your battery will ensure you are not stuck in a difficult situation where you are unable to start your car. Indicators to look out for include:

Slow engine start up

If you have noticed that your car engine has become sluggish, taking longer to start and making a noise which is out of the ordinary, it could mean you need to replace your battery.

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Warning light

Warning lights in your car are an easy way to identify problems with your vehicle. With regard to your battery, there are two lights which you should acknowledge: the engine light and the battery light. The “check engine” light can illuminate if your battery power is weak. Typically, if the light is constant, then the problem is not urgent, but you should still identify the issue and get it fixed as soon as possible. On the other hand, if your engine light is flashing, this indicates there is a fault which requires immediate attention.

If your battery warning light illuminates, this indicates there is an issue with its voltage level, and your vehicle’s charging system is not working correctly. This could be as a result of a loose or corroded battery cable or a problem with the voltage regulator.

Battery fluid level

Ensuring your battery fluid levels are correct is crucial to maintaining battery life. The liquid within a battery is a mixture of sulfuric acid and electrolyte-infused (distilled) water. This mixture is pivotal to the functioning of modern batteries as the electrolytes allow currents to pass between the electrodes within each cell. More information on how you can check electrolyte levels in your battery can be found here. It is recommended that you check your battery fluid level at least once a month.

Swollen battery case

Excessive heat can cause your battery to swell, damaging it permanently. If you see your battery has swollen, it needs to be replaced immediately.


If you notice pungent, rotten egg smell (sulfur odour) around your battery, it is an indication that your batteries may have leaked. Leaking can lead to corrosion, so it is best to resolve the issue as soon as possible before the damage becomes irreversible.


The most popular solution when it comes to reviving car batteries is jumpstarting. For this method, all you need are some jump leads and a working car (preferably with an engine size similar to your own vehicle) To jump-start effectively, both vehicles must be parked near each other, but not touching, so the cables can easily reach both cars.

The red lead needs to be connected to the positive terminals on each battery. Then, one end of the black lead needs to be connected to the negative terminal on the working battery, and the other end connected to a metal feature away from the dead battery, such as a bolt. To see if your car has negative jump-starting poles, you should refer to your handbook.

Once you have checked that the leads are away from moving parts, the engine of the working car should now be started. After a couple of minutes have passed, you should now attempt to start the car with the dead battery. If the car still doesn’t work, continue jumpstarting the car for a little longer but be cautious of the leads getting too hot (at which point you should switch off the engine).

When the car is running, leave the engine on for a couple of minutes so that the battery is sufficiently charged. You should then remove the jump leads in the reverse order to which you attached them. When doing this, you must make sure they do not touch each other or any metal surfaces.

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Distilled Water

As opposed to tap water, distilled water does not contain unwanted minerals which do not evaporate alongside the water. If you use tap water for your car battery, you increase the risk of minerals such as iron and calcium being left behind. These minerals attract free-flowing electrons and form a compound that is not needed inside the battery. This mineral build up will ultimately decrease the lifespan of your car battery.

Distilled water does not contain any minerals or substances which will negatively impact your battery. Unlike tap water, when distilled water evaporates it will not leave any unnecessary minerals behind. To maximise the longevity of your car battery, distilled water is the best option as it does not affect the chemical processes which occur inside the battery. Remeber, when filling your batteries with water, they should just cover the plates of each cell.

Distilled water can be bought from supermarkets, hardware shops and online retailers. This is one of the cheapest yet most effective solutions you can use to revive your car batteries.

Looking after your car

Regular checks and maintenance of your car batteries is just one way in which you can personally keep your car in working condition. However, seeking professional assistance is always worth the investment, and having a Car Service in Milton Keynes means experienced and trained technicians will thoroughly check your vehicle.

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