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What battery for my car?

Ellie Dyer- Brown, 7 months ago

3 min read

  • Advice
  • Maintenance
Mechanic inspecting car battery

WhoCanFIxMyCar looks at the different types of car battery that are available

There’s no doubt that car batteries are important - after all, you wouldn’t be able to drive anywhere without one - which is why you should always select the best battery for your vehicle. 

How do you know what car battery you need? Well, each car is slightly different and has slightly different needs, so any battery you choose will need to meet these individual requirements.

Contents:

What car battery do I need?

How long do car batteries last?

Signs your battery is faulty

How long to leave a car running to charge the battery

Why does my battery keep dying?

Frequently asked questions


What car battery do I need?

There are a number of different types of battery available.

  • 12 volt lead-acid batteries are the most common type found in traditional internal combustion engine cars

  • Premium calcium batteries can offer over 30% more starting power, but they’re also expensive, so you only need to consider calcium if your car is more powerful than average

  • Most electric vehicles use Lithium ion (Li-io) batteries

  • Hybrid vehicles often have nickel-metal hydride batteries

  • Enhanced Cyclic Mat (ECM) batteries are usually used in entry-level start/stop vehicles

  • Larger and more demanding stop/start vehicles tend to use Absorbent Glass Mat (AGM) batteries

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How long do car batteries last?

There are no hard and fast rules when it comes to the average lifespan of a car battery, although, in general, they tend to last between three to five years.

The best way to make your battery last for years is to take good care of it. Find out how in this video by our partners at Varta.

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Signs your battery is faulty

Not all batteries will give you advance warning that they are about to fail, but generally there are a number of tell-tale signs that your car battery could be on the way out.

Battery warning light

The first and most obvious one is the battery warning light on your dashboard. If that lights up, then it’s time to get it checked over by professional. It might be nothing but it’s always advisable to ask the experts at the earliest opportunity.

Car struggles to start

If your car struggles to start, especially if it’s not cold, then this could be a sign of a problem with your battery. Many garages will offer you a free battery health check where they will be able to advise on the condition of your battery and next steps.

Headlights are very dim

Another sign that there might be an issue is your headlights all of a sudden become very dim, even when the engine is on. When your battery is low, it can often supply sufficient power for things such as the radio but struggles with greater drains on its power such as headlights.

Car starts but then stops straightaway

This is definitely up there as one of the most frustrating things that can happen, especially on a cold and frosty morning. The battery has enough power to start the car but not enough for it to be left idling.  


How long to leave a car running to charge the battery

When you’re trying to recharge your battery after using jump leads, simply allowing it to idle on the driveway isn’t enough. Instead you should aim to drive continuously for at least 30 minutes to ensure the battery has charged enough.


Why does my battery keep dying?

Cold weather

Cold weather is the number one reason why car batteries fail. As soon as the temperature plummets, so does the performance of your car battery, in some instances by as much as 60 per cent. If your car battery is struggling anyway, this can often be the last straw and you will be looking at a replacement if you can’t bring it to life – even after a recharge or a jump start.

Lack of use

The longer you go between drives, the less likely your car is to start up. Car batteries are charged by the alternator, which only works if the car is running. If you’ve not been driving your car on a regular basis, for whatever reason, this will reduce the charge held within the battery, potentially creating issues when it comes to starting.

One of the best ways of combating this age old problem is by investing in a battery charger. 

Corrosion

One of the other main causes of car battery failure is corrosion. The simplest way to check is to lift the bonnet and check the battery terminals. If you see either a blue or green deposit (or alternatively a white powder like substance) on the connections, that’s a sign that your battery has been slightly damaged by corrosion and this could be affecting your car's ability to charge. 

Don’t worry, this is quite normal and can be rectified either by using a cloth to wipe away the deposits, or if this doesn’t work, using a stiff wire brush to gently remove the corrosion.


Frequently asked questions

What does mAh mean on a battery?

A. It stands for milliampere hour and is a measurement of energy stored in a battery. However, for more powerful batteries such as those used in cars, you’ll be looking at Ah (ampere hours) instead.

What does Ah mean on a battery?

As mentioned above, Ah stands for Ampere hours. To put it simply, Ah refers to the number of Amps you can get out of a battery when it is operating continuously for an hour. Essentially, it’s a measurement that tells you how long a battery will last when performing a particular task.

What is an AGM battery?

First developed in the 1980s for military use, Absorbent Glass Mat batteries offer a high-level of performance that is suited to modern cars which often contain complex electrical systems. This is particularly true when it comes to stop/start vehicles. 

Traditional Lithium-ion starter batteries aren’t equipped to handle the strain of continuously charging and discharging which is associated with start/stop vehicles.


If you think your car's battery is on the way out, WhoCanFixMyCar can help you find a reliable local mechanic who will fit a new battery and get you back on the road in no time.

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