How a Car Battery Works for Standard and Start-Stop Vehicles

Did you know that in Australia alone, the average car emits twice its weight in greenhouse gasses each year? That’s why so many car manufacturers have developed start stop engine systems.

In a start stop system, your car’s engine shuts down when you pull up to a signal and put your foot on the brake. Your lights, radio, and wipers keep working, but your engine shuts off, reducing emissions. Take your foot off the brake, and your engine restarts. That’s great for the environment but rough on your car’s battery.

With the market for start stop vehicles expected to double between 2018 and 2026, drivers need to know the difference between standard car batteries and the batteries used in start stop cars. So let’s take a look.

The Basics: What Are Car Batteries

Batteries are an essential part of every car. No battery (or a dead battery), and your car won’t start. No battery, and your accessories – radio, lights, wipers – won’t work.

Lead Acid Batteries

Lead Acid (wet cell) batteries – the standard in cars – have been around since 1859. Now, without getting too ‘techie,’ here’s how all batteries work. Batteries use a chemical reaction to produce electrical energy. A typical car battery has lead and dioxide plates floating in sulphuric acid. Turning on the ignition starts a chemical reaction, producing electricity.

At rest, a healthy car battery will have 12.65 volts. When the car’s running and the alternator is charging the battery, the voltage will be 13.7 to 14.7 volts. That’s more than enough to start the engine, keep the spark plugs firing, and power any accessories.

Designed for the Job

Starting a car means the battery must put out a big surge of electricity all at once. That reduces the battery’s charge. But once the engine’s running, the battery is brought back -up to full charge reasonably quickly.

Standard lead-acid car batteries are designed knowing that they’ll be asked to pump out lots of current to start the engine a handful of times a day. Quality lead-acid batteries – like those from RB Battery in Thailand – are designed with the heat and humidity of Southeast Asia and Australia in mind. Even in extreme conditions, these batteries will keep doing their job for years.

Start Stop AGM Batteries

Saving fuel and reducing greenhouse gas emissions – the reason car manufacturers developed start stop technology – is a good thing. But not for standard lead-acid batteries.

Asking a regular car battery to start the engine dozens of times a day will quickly wear out the battery. It’s simply not designed to take that kind of abuse. And on top of the need to frequently start the engine, batteries in start stop cars need to keep all the accessories running when the engine is off.

Frequent starting demands and the constant drain of powering the car’s lights, wipers, air conditioning, and stereo is a big ask! And that meant battery manufacturers needed to develop a whole new battery technology. Enter the Absorbed Glass Mat (AGM) battery.

AGM Battery Design

Like its cousin, the lead-acid battery, an AGM battery has positive and negative plates. The big difference is that the electrolyte isn’t sloshing around between the plates.

In an AGM, absorbent, sponge-like glass mats (like fibreglass) are put between the plates. The electrolyte is held in the glass mats. That means that the electrolyte is in much tighter contact with the positive and negative plates. And that’s where the advantages of AGMs come from.

AGMs represent the pinnacle of lead-acid battery design.

What Makes an AGM Different?

First, there’s the fact that AGMs cells are more tightly packed. That means more surface contact. That reduces electrical resistance internally and cuts down on the erosion of the plates. All of that adds up to longer battery life.

All lead-acid batteries emit gasses as the chemical reaction takes place. Vents in a standard car battery allow that gas to escape into the atmosphere. AGMs, on the other hand, give off much less gas.

Because there’s less gas produced and given off, AGMs don’t have vent caps. Instead, the gas is held internally and recombined into the electrolyte. However, AGMs do have a one-way safety valve that protects the battery in the event of overcharging.

What Are the Advantages of AGMs?

AGMs offer a lot of advantages over standard car batteries. Because they are non-venting, they are maintenance-free. That means you don’t have to check – and occasionally top off – the electrolyte.

Their construction, using glass mats between the plates, means they are more rugged. They can stand vibration and impact that would damage a regular lead-acid battery.

With the tighter packing between the cells and the fact that the electrolyte is in closer contact with the plates, other benefits come into play.

AGMs offer more power in a smaller package. Compare an AGM and a standard car battery of equal size, and the AGM will put out 35% more power.

AGMs are excellent in deep-cycle roles – that’s the ability to provide continuous power for a car’s accessories. But they also deliver the high-cranking power needed to start the engine.

Last – and not least – they last longer with much-improved cycle life. That makes them ideal in today’s start stop vehicles!

RB Battery makes a complete line of car batteries designed for the harsh conditions often found in Africa, Asia, and the Middle East. For a complete car battery guide from RB Battery, click here.

Choosing the Right Battery for Your Car

What type of battery is right for your car? Whether your car needs a regular car battery or one designed for start stop, you need a battery designed and built to do a tough job under harsh conditions. In addition, you want a battery that’s affordable, rugged, and proven.

That’s why RB automotive batteries are a top choice for car owners across Africa, Asia, and the Middle East. Contact RB Battery today at their headquarters in Bangkok. They’ll be glad to offer technical support, specific battery recommendations, availability, or more information!