What does a car battery do and how does it work?
What does a car battery do?
Car batteries aren't an optional extra - you'd be left at a standstill without one!
Starting - when you put your key in the ignition and give it that first half-turn to wake it up, your car battery is making that possible. You can run your air vents, turn on the interior lights, check the dashboard lights or listen to the radio without having to turn the engine on thanks to your battery. Be careful if you do any of this for an extended period of time without the engine running, as you'll soon run out of charge!
Lighting - your interior lights, indicators and of course rear and main headlights run straight off the battery. This means you can still see (and be seen) while parked up with the engine switched off. Alongside the lights, car batteries also power the other electrical items you can fit to your car or plug into the 12V power outlet, including Sat-Navs, phone chargers, DVD players and even mini fridges for those camping trips!
Ignition - batteries provide electricity to the spark plugs or heating elements, the bits that light the fuel in your engine and make it run.
How do car batteries work?
Just like normal batteries, car batteries use a chemical reaction to generate the electricity needed to run the lights or start the engine. When the key is half-turned in the ignition, a chemical reaction takes place, with electricity released to the car's systems from the battery. Over time, the battery will lose its charge, but luckily the reaction can be reversed, allowing energy to be stored in the battery ready for the next time the engine needs to be started. This is known as 'charging' the battery.