One of the most essential parts of your car is its battery. If you look under the hood of your vehicle, you'll find an automotive battery sitting quietly among the many other components in there. They do their work quietly through their lifespan of at least a couple of years, so you don't have to replace them often.

Usually, these batteries are designed to deliver a strong electrical current but only for short periods at a time. The battery does most of its work when you activate the ignition to start the car. When the engine’s already on, the battery then focuses on powering the electrical systems in the car.

However, some car models actually start and stop their engines automatically many times during a journey. These cars have what's known as a 'start-stop system'. With this system, there is a higher demand placed on the car battery, which could reduce its lifespan dramatically.

So this begs the question: does a start-stop car need a different kind of battery? And if so, why can’t we just use regular car batteries for them?

How Do Car Batteries Work?

A car battery is a simple piece of equipment that enables the first spark (literally!) that starts the combustion process and gets your engine going. Once it's started, you can begin your journey and drive that car to wherever you need to go.

Like most batteries, an automotive battery is a device that turns chemical energy into electricity. Inside the battery, there's a lead-acid chemical reaction that takes place which generates electricity that flows throughout the car’s electrical systems.

Automotive batteries are widely known as the 'SLI' type, which stands for 'starting, lighting, and engine'. What this means is that your battery serves three specific purposes, most notably starting the engine as mentioned before. Once the car is already running, the battery provides power for the car's engine, its lights and all the accessories as well.

While you're driving your car, another part called the alternator provides energy back to the battery to keep it charged up.

These batteries are highly-reliable for normal cars, but they will not last long if used in a car with a start-stop system.

What Are Start-Stop Cars?

'Start-stop cars' are equipped with a system that automatically shuts the car engine down whenever it comes to a halt. As the driver accelerates to move again, the vehicle will instantly restart its engine. This system avoids idling the engine and in doing so, saves fuel and reduces emissions.

As the name suggests, a start-stop car's engine will start and stop many times in a single journey. This repetitive process puts a massive burden on a standard car battery and significantly reduce its lifespan. This is simply because a standard car battery is simply not designed to deliver electric charges so as often as needed by a start-stop car.

Thankfully, automotive battery manufacturers have designed other kinds of batteries that are able to keep up with this demand.

What Types of Batteries Are There for a Start-Stop Car?

Two types of car batteries can handle the demands of a start-stop car: the Enhanced Cyclic Mat (ECM) and Absorbent Glass Mat (AGM) types of batteries.

The ECM battery is known by many names including the Advanced Flooded Battery (AFB) and Enhanced Flooded Battery (EFB). No matter what name you use, it's a basic battery that's suitable for use in start-stop cars. This is because the battery is much more durable and allows the vehicle to use more of the battery's capacity without losing its performance. This kind of battery also provides a more consistent flow of power. It can recharge much faster, perfect for a start-stop system that will need to use that power more frequently.

The AGM battery, on the other hand, is much more sophisticated. Inside this battery, acid is absorbed into fibreglass materials, and not just flowing around like they do in regular batteries. This feature is important because just like the ECM type, it means the AGM battery can handle the high demands of a start-stop system while maintaining its long lifespan.

Maintaining Your Car Battery

No matter what vehicle you drive, it's essential to get the correct automotive battery for your car. It's equally important to take the proper steps to ensure the health of the battery and maximize its lifespan. 

Making the most of your car battery's lifespan is easy. First, make sure that it's secure in its place under the hood. Next, always make sure you turn off all lights when you exit the vehicle to avoid draining its power. If you don't use the car daily, be sure to take it for a long drive once in a while, just so the battery has a chance to recharge completely. 

Last but not least, be sure to test your battery from time to time. Whenever you take your car to the workshop for whatever reason, be sure to ask them to check the battery as well. A battery test is usually very quick and very cheap to do (if they charge you at all). By doing this, you'll be able to pre-emptively replace the battery instead of waiting until you’re stranded somewhere looking for a replacement.