Which battery for my car?

The car battery actually only has one job, why all the different versions?

Sure, the car battery starts the car. It quickly emits a lot of current, which can be measured: the cold start power in CCA or the cold test current is the current that a starter battery can deliver for a short time, the capacity in ampere hours x (Ah) is the amount of current that a battery can deliver over time.

It is charged by the alternator while driving. Ideally, current output (= discharging) and current consumption (= charging) are in balance.

However, this is not the only task. In cars that are driven a lot on short journeys, for example, and have a lot of electronic equipment, the alternator can reach its limits. Then the battery has to take over the energy supply.

Modern cars also switch off the engine when they stop, e.g. at red lights. The battery is then responsible for ensuring that the lights and radio stay on and the air conditioning continues to cool or heat.

It also has to start the engine much more often in vehicles with a start-stop system. On the other hand, these cars also recover energy, i.e. electricity, when braking and use it to charge the battery or to supply power. This power generation is called recuperation.

The battery has therefore gained significantly more tasks. And there are different approaches to managing them. So when you need a new battery, all of this plays a role.

Helpful questions when choosing a car battery

• How much equipment does your vehicle have?
• What does the battery have to do while driving?
• Do you drive extremely short distances?
• Does your alternator even have time to charge the battery before it has to supply power again?
• Does your car start several times during a journey because it has a start-stop function?

In the next few paragraphs, we will take a closer look at which battery makes sense and when.

For well-equipped vehicles: intAct Premium-Power, our high-end lead-acid series

Electric windows, air conditioning and heated seats are no longer an exception in new cars. Here, the battery not only has to start the engine, but also has work to do while driving. More power has to be supplied. If you are often on the road in city traffic or the car is sometimes left standing for longer periods, the intAct Premium Power, our high-end battery, is our clear recommendation for cars with a high level of comfort and without a start-stop function.

The space for the battery in the car is limited. To accommodate more power in the same space, there are numerous improvements inside this battery. The special alloy and grid shape can also handle small amounts of charge. This ensures that it lasts longer than the intAct Start-Power, even in critical supply situations.

Advantages

Like the intAct Start-Power, it has a double lid with a labyrinth for increased leakage protection and so that any gas produced is not lost but condensed. 
All types in this series are approved for a charging voltage of 14.8 V and higher, as supplied by modern alternators.
Minimal self-discharge when not in use.

to our intAct Premium-Power batteries

How big can the car battery be?

You don't have much choice here. The battery must fit in the space provided and this is limited. If it's too big or much too small, even the best battery won't do you any good. Specifically, it's about the length, width or depth and height of the battery, always in that order and usually in millimeters.

There is now an ETN number, but even this is not unique and is only valid in the EU. In Japan there is the JIS and in the US there are numerous different battery sizes.

You have several options to ensure that your new battery fits:

• Take the number from the old battery.
• Measure it yourself - the easiest way is with these instructions.
• Look in your car manual. 
• Check the technical data of your old battery model with the manufacturer.
• Enter the KBA number from your vehicle registration document in our battery finder and have the right batteries conveniently displayed.

Does a more powerful battery make sense? And how much power do you really need?

Basically, a newly installed battery is designed for your car. Over time, however, it loses performance and ages. Until it fails. If you determine your new battery based on the old battery dimensions or the KBA number, in most cases you will receive several suggestions for your vehicle. The vehicle handbook also usually suggests a range of performance values.

Accordingly, battery manufacturers have different battery models that offer more or less capacity (ampere hours, Ah) or cold test current (A) in the same space.

The capacity required by your vehicle depends on the engine displacement and the equipment. The larger the displacement, the more power is required when starting, and even more for diesel engines. If your car is equipped with electric seat, steering wheel or mirror adjustments, a navigation system or seat heating, the battery must provide even more power on a permanent basis.

So which power should you choose?

• By no means lower than required.
• The same capacity is perfectly okay.
• A higher capacity can make sense if your battery reached its limits from the start, or if you have retrofitted things that consume power.

Tip: If you maintain and charge your battery regularly, it will not lose power as quickly. A battery that is constantly overloaded ages more quickly. Even a larger capacity won't help.