What is a car battery

Don’t let your battery inconvenience your Holiday Plans

Car batteries can fail at the most inconvenient of timesCentury-Heavy-Duty

Battery failure is one of the leading causes of starting trouble, whether because of lights being left on, a charging system problem or other causes. Or in some cases the battery has met its life expectancy.

What is a car battery?

Your vehicle battery's main role is to provide starting power for the engine.

It also supplies power to accessories such as lights, fans, radio and electronic components when the engine is not running.

Batteries produce their power through a chemical reaction which is released when a load such as a globe, starter motor or electric fan is connected to the battery.  Electrical current is generated when two different metals are placed separately in a liquid capable of conducting electricity.

How does a battery work?

When you turn the key to start the vehicle a lot of things happen, the first thing that will happen is that the battery in your car will start to lose voltage.

The reason for this is that the battery is concentrating on turning the starter motor to make the vehicle start. Once the vehicle starts then the alternator charges the battery back-up. So the battery will constantly drain and recharge every single time you start and drive your vehicle.

The next thing that will happen is that the starter motors gears will try and engage with the flywheel or ring gear of the engine. To make an engine start it must be turned at speed; this will allow fuel and air to be drawn into the cylinders, compress it and make the vehicle start.

In simple terms the battery provides the power, the starter motor turns the ring gear on the flywheel which turns the engine, add a bit of fuel, air and spark and the engine should start.

So think about how many times you start your car every week, the above is happening on a regular basis. 

Over time these components will eventually wear out, reasons that can speed up your battery wearing out are:

  • Charge Rates  - If your battery is not charging properly it may reduce the battery life
  • Excessive Vibration  - Excessive vibrations going through the battery may reduce the battery life this may be caused by a loose hold down clamp
  • High Loads – leaving lights on, having multiple sources drawing power from the battery will lessen the life
  • Electrical System Faults – Faults within the electrical system can cause the battery not to recharge fully
  • Loose or dirty Terminals – By not getting a clean connection a loose or dirty terminal could also cause battery issues
  • Stop/Start Motoring  - by traveling a short distance this may not be enough time for your battery to charge up
  • Sulphation – A sulphated battery is one which has been left standing in a discharged condition or undercharged to the point lead sulphate has and can cause impeded and loss of capacity.

It all starts with the battery so it’s important that the car battery is inspected and tested on a regular basis this can be done at anyone of our stores for no charge.

Your local Kmart Tyre & Auto Service store will:

  • Test your battery to assess its current condition
  • Check and top up the battery electrolyte level
  • Ensure the battery terminal & leads are in good condition
  • Check the alternator charge rate
  • Advise you of any required maintenance

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