Car battery myths

There are countless myths about car batteries so we’re here to sort the facts from the old wives’ tales.

  1. After leaving the lights on and consequently flattening the battery, you can recharge it by going for a drive.
    This is a myth. Doing this will only ‘surface’ charge the battery and doing this continuously will result in a shortened battery life and could void your battery warranty.
  2. If you won’t be driving your car for a few weeks you should disconnect the battery.
    This is false — not only will disconnecting the battery not prolong its life it can also cause systems which require constant power, such as alarms, steering, transmission and electronics, to stop working even when the battery is reconnected.
  3. Cars that aren’t driven regularly will get flat batteries.
    This is true. Batteries naturally slowly leak power, so over time the battery will gradually lose charge and go flat if not regularly boosted from driving.
  4. A flat battery can affect fuel economy.
    This is true, as a car’s alternator will automatically try to recharge a flat battery. Due to this added load, the car will burn through fuel faster.
  5. Batteries last longer in warmer climates.
    This is false, as hot climates drain car batteries due to water loss and heat distortion. There are, however heat shields, and maintenance-free batteries available which combat this problem.
  6. Batteries have a set lifespan.
    This is false, as how long a battery lasts depends on how often the car is used, the climate, proper installation as well as car and battery maintenance. There are however battery warranties available to ensure the battery lasts for a suitable time period.

For more battery myth busting visit the RACQ website.