Choosing a car battery always involves a few important questions that you should know the answers to, before you finalise the purchase. Type, dimensions, starting current (CCA) or battery capacity are just a few of them. Here’s a guide to choosing and buying the right battery for your car.

Battery is the heart of an engine and a car. It is thanks to the battery that we can go on a long journey even when the temperatures are terribly low. It also provides power for the radio or heated seats. Battery wear is a natural process of a battery going flat that leads to battery replacement. But choosing the right battery is no longer easy or obvious.

In the guide below, we will answer questions such as: how to choose appropriate battery for your car, or what criteria to follow – electrical and technical parameters, size, terminal connection or battery type.

If you don’t have the soul of a mechanic in you, technical issues don’t interest you or you don’t feel like analysing catalogues with different names and types of batteries, entrust the matter of battery selection to a specialist at once. You will find qualified and comprehensive assistance in the Motointegrator garage network. 

Which battery is best for your car – where to find information?

You should start your search from checking the manual of your car. There you will find specified parameters, such as type, size or capacity and cranking amperage, which will allow proper selection of a battery. Experience and knowledge of specialists advise that it is not worth using batteries which do not comply with recommendations of car manufacturer.  

Battery type: maintenance, acid, gel, AGM…

Lead-acid batteries are the basic type of battery. They are characterised by a good ratio of quality, durability and price. Standard (maintainable) batteries used to be popular – they required filling in and/or topping up of electrolyte. However, technological progress caused that they were replaced by maintenance-free batteries, having a window to check the state of charge. They work well in most popular cars.

Other types of batteries are GEL and AGM. In GEL batteries, electrolyte is in the form of gel, and their application is limited mainly to powersport vehicles or motorcycles. Low weight, high shock resistance with not too high starting current is important there. AGM on the other, hand have special fibre separators that absorb the electrolyte. They are often characterised by higher capacity and starting current.

EFB (Enhanced Flooded Battery), AFB (Advanced Flooded Battery) or ECM (Enhanced Cycling Mat) – marking depends on manufacturer, but ideology remains the same. These are batteries with extended life, suited to more frequent engine cranking and powering electrical systems. They are developed for cars equipped with Start&Stop systems.

Which type to choose?

We recommend you choose proven batteries from renowned brands. This way, we minimize the risk of incorrect selection of batteries to the type of installation you have. Battery manufacturers and car producers are unanimous – battery type should not be changed in relation to factory recommendations.

Battery voltage – 12 V

Fortunately, this problem is practically negligible. All passenger cars found on the road are compatible with 12 V (twelve volt) installation. Cars from several decades ago had 6 volt systems, while all trucks run on 24 volts. So, we reassure you – accidentally buying a battery that has a voltage other than 12 volts is improbable.

Battery capacity – how many ampere-hours (Ah)?

This is one of the two most important battery values. It literally defines its current capacity. The general rule is: the more electric receivers in the car (modern electrical systems), the higher battery capacity must be. However, it will be a mistake to buy a battery with the highest available capacity.

You should choose such an amp-hour capacity as suggested by car manufacturer. Why? Because it is strictly connected with possibilities of an alternator, and also with type of engine or having Start&Stop system and with character of vehicle use. A battery that is too “large” may be constantly undercharged because the alternator cannot provide proper charging. A battery that is too ‘small’, on the other hand, may not provide power for all the devices such as the radio, seat heating, electric windows or a GPS system.

Some experts advise that a battery with at most 10% more capacity than the factory capacity can be fitted. The Audi catalogue for the 2.0TFSI engine, on the other hand, lists capacities from 56 Ah to as much as 72 Ah. Much depends also on how the vehicle is used – if these are mainly short journeys and the prevailing climate is rather cold, a change to a larger battery is not recommended. The alternator will not have time to recharge it.

Battery cranking current – how many amperes (A)?

The second most important battery parameter is cranking current, which is a value defining one-time, short-term current output that a battery is able to generate. It is current delivered to starter, which task is to rotate the crankshaft of engine. As a general rule, the greater the capacity or power of the engine, the greater the resistance and therefore the greater the cranking current required. Petrol engines require less current, while diesel engines require more, it also depends on the type of starter used and the presence of the Start&Stop system.

When determining this parameter, it is therefore worth following the manufacturer’s recommendations. Value of cranking current is connected with physical dimensions of battery, but also with its price. Another problem concerns the fact that increased starting current, translates into higher chance of discharging battery with installation fitted to “smaller” battery.

Hold-down ramp and battery size

Physical dimensions of battery should be precisely matched. In many cars, the battery is located under the hood, sometimes under the seats, sometimes in the boot, but always the battery space has a specific size and way of fitting. Therefore, before buying it is necessary to verify what dimension is given by manufacturer.
It is also worth to check how battery is assembled on a car. Most often it is assembled with a metal clamp, from above. But sometimes it is a clip on the hold-down ramp, that is on the bottom plate of the battery. This is indicated by a mark, for example B13.

Shape and terminal position

When talking about the size of the battery, one cannot forget to mention the position of its terminals. Before choosing, you should verify whether you need “right positive” or “left positive”. Sometimes the same battery is available in both versions, and having chosen incorrectly, car electric wires simply won’t reach proper places.
Important parameter is also shape of terminals. Vast majority of cars have round terminals, Asian cars may have round terminals with small diameters, other cars have side screw terminals, and tin screw terminals.

Where to find a good battery?

Summarizing, size does matter when it comes to batteries, but bigger and stronger does not mean better. Choose your battery carefully and according to vehicle manufacturer’s recommendations. These recommendations can be found in your car instruction manual. Choose from renowned manufacturers, and get your knowledge from reliable sources. Buy your battery from a reputable source to avoid long-stored batteries with poor performance.
A wide and reliable selection of car batteries, together with comprehensive assistance of a qualified specialist, as well as with high quality replacement service, can be found in Inter Cars branches or at shop.