car battery replacment

Car Battery Guide - Types and Sizes

If you’ve ever turned your ignition key and had that sinking feeling as your car ignition gets progressively slower and slower, you’ll know just how important your car battery is. Keeping it charged and ready to go is vital – without a good battery, you’re going nowhere. But what kind of battery do you need? And what size?

What does a battery do?

A car battery is the heart of your vehicle. It supplies an electrical current to the starter, which turns the engine over to get it running. It also powers all of the electrical components on your vehicle, from the lights, electric windows and the heated seats to your onboard infotainment centre and onboard vehicle computers. With so much being asked of your car battery (even when the car is turned off), it’s essential that part of your regular car maintenance checklist includes ensuring that the battery is in good condition.

If you have to replace it, you need to know which size battery you need, and what type is best for your car. However, not all batteries are the same, and you need to consider not just the size, but a variety of factors including the location and type of the terminals, the number of cells a battery has, the voltage it produces, and the cold cranking amperage or CCA.

You’ll also need to know what Amp/hour rating you need for your vehicle. This is the amount of amps a battery can deliver in one hour, which determines how much power it can both store and deliver on-demand. However, it’s worth noting that not all manufacturers use the same system, which makes things a little confusing, to say the least!

Battery sizes

The size of a battery does not necessarily just refer to its dimensions but also takes into account the position of the terminals, and which type is recommended for your vehicle. The sizes are indicated by specific letters and numbers, based on engine type, make, and model. Side terminal post batteries are usually numbered as 70, 74, 75, and 78. Recessed top terminal post batteries are used in some European cars such as BMW and Mercedes. They’re commonly referred to as ‘international style’ batteries and are numbered 41, 42, 47, 48, and 49.

Finally, the most common type of battery size is the standard top post battery, used extensively in Japanese, European and American cars. Look out for the group size numbers 24, 24F, 25, 34, 35, 51, 51R, 52, 58, 58R, 59, and 65.

Car battery types

There are several different types of battery, but the most common version you’ll find on vehicles is the Wet Cell Battery Type or "Flooded Battery". These batteries are one of the oldest battery designs and are made up of lead plates that sit in an electrolyte solution made up of acid and distilled water. They’re simple, cheap, and easily replaced, but they will need regular maintaining. If they run dry or leak then it can cause problems.

An alternative is a Dry Cell battery. They still contain liquid but are sealed so that they won’t leak or spill. They’re maintenance-free but more expensive than traditional wet cell batteries.

More exotic types of batteries include Absorbed Glass Mat or AGM batteries that use fibre-glass between the plates to absorb the acid, and Lead-Acid Gel Cell batteries, also known as sealed lead-acid batteries. These use different compounds to suspend the acid into a gel or fibre-glass format, stopping them from leaking or spilling. They’re expensive, but they do last longer.

How long does a battery last?

The lifespan of the average battery is around three years, but a variety of factors can affect that number, especially temperature. The hotter the ambient temperature, the faster the electrolytes in the battery evaporate the water in a wet cell design. A dry battery is a dead battery. So if that battery light comes on, don’t ignore it!

At Al-Futtaim FastFit, our technicians can carry out car battery checks quickly and easily. They’ll make sure your car battery voltage is at the correct level, and that it’s in tip-top condition. And if it’s looking a little worse for wear, not holding a charge properly, or you’re having difficulties starting, they’ll carry out a car battery replacement for you.

Your battery is the beating heart of your vehicle. Trust Al-Futtaim FastFit to look after it for you, so you can keep moving!