Stop-Start Car Battery Technology: Clear Up The Confusion

What Is The Stop-Start System?

The name of this particular piece of technology pretty much sums up its function; your engine is cut when your vehicle is at a standstill, and then it starts again when you press on the clutch or ease off the brakes, ready to head off. A pretty simple explanation for a complex system.

Most modern vehicles are equipped with this handy system, to essentially reduce the amount of fuel your engine consumes and decrease your vehicle’s emissions.

How Does This System Work?

With this system, thankfully, you don’t have to put in any extra input, like pressing a button to activate the stop-start technology. There is a computer in your vehicle that monitors your driving and senses when you’re stationary or when you’re in neutral (not in any gear). With this detection, fuel stops being supplied to the engine and the spark plug isn’t fired, so your engine isn’t running whilst you’re idle in traffic, for example.

When you’re ready to set off again, for example, when you engage the clutch or start to move the vehicle forward, the ignition will start up again and the engine will continue running.

Approximately 60% of the vehicles that are sold in Europe currently have either start-stop technology or brake energy recovery technology.

Brake energy recovery technology, also known as a concept called regenerative brakes, is technology that will allow the energy that is usually wasted when a car brakes to be stored and used when the vehicle starts again. Essentially, kinetic energy will be stored in a battery when you stop, and then when the vehicle starts up again, the stored kinetic energy will be transferred to the wheels, thus re-using the energy instead of it being wasted and turned to heat energy.

Now, back to stop-start, it’s estimated that fuel consumption will be decreased by between 5-10%, just from the use of this technology!

One technicality though, a normal lead acid battery cannot run this system, so special batteries are needed: Absorbent Glass Mat (AGM) and Enhanced Flooded Batteries (EFB).

Are Different Batteries Required For This Stop-Start Technology? If So, Why?

For this particular system, the typical lead-acid batteries will not work as efficiently as the two specific batteries specialised for this exact system. These two are the Absorbent Glass Mat (AGM) and Enhanced Flooded Batteries (EFB), which are designed to last for a longer period of time than the normal battery.

When the ‘stop’ part of the system is engaged (engine is off), these batteries possess abundant charge in order to be durable enough to keep the electrical components in the vehicle running, such as the air conditioning, audio system and windscreen wipers.

Furthermore, these batteries must be strong enough to handle the vehicle being started many times (ignition), as opposed to the one start in a non stop-start vehicle. For example, travelling through traffic, or encountering many red lights through your journey will mean you will be stopping and starting numerous times, therefore a much stronger battery will be needed to provide the required energy.

When the time comes to pick an AGM or EFB battery for your stop-start car, it’s recommended to pick a quality one that has good reviews from car manufacturers and drivers, one that has the confidence of both groups.

AGM Advanced Technology – VARTA Silver Dynamic AGM

As more vehicles are being equipped with start-stop technology, it has led to an advancement in battery technology, due to the fact that lead acid batteries do not meet the needs of this specific system.

A particularly popular and recommended AGM battery that is now used in 80% of newly manufactured AGM battery powered stop-start vehicles in Europe, is the VARTA Silver Dynamic AGM. Compared to the life of usual batteries, the VARTA Silver Dynamic AGM has 3 times the cycle life, which will definitely meet the needs of vehicles that require a higher amount of energy.

This battery (VARTA AGM) is factory-made according to OE (Original Equipment) specifications, meaning that it ensures a like-for-like replacement for the original battery in your stop-start vehicle, thus providing identical performance and lifetime. Furthermore, if your vehicle is equipped with an AGM battery, it is recommended that when you replace the battery, you stick to using an AGM one. As mentioned previously, this is due to the fact that conventional batteries are not powerful enough to meet the great energy demand of stop-start in modern vehicles.