How to take care of your car battery

Safety and care of your battery

How long should my car battery last? 

This depends on:

  • proper installation
  • the climate in which the car operates
  • how regularly the car is driven
  • how regularly the battery and car are maintained

All AA batteries are guaranteed for the term of the warranty providing you properly maintain your battery and regularly use your vehicle. Read our battery terms & conditions.

Why it's important to check your car battery? 

Your car battery may look good on the outside, but what’s going on inside it can be a different story.  If you battery is feeling a sluggish start or you can see any visible wear, this can indicate you may need a new battery. We recommend having your battery checked and tested by a professional.

Always remember to turn off all lights before you leave your car.

Check your electrical connections

Make sure battery terminals and cable connections are clean and tight to enable proper current flow. Corrosion at the battery terminals can prevent a car from starting by adding electrical resistance, so it is important to clean the terminals periodically using water and a wire brush. Ensure you wear the correct protective gear (gloves and eye protection) as the white powder (lead sulphate) is toxic if inhaled, ingested or comes into contact with your skin.

Keep batteries clean and dry

A dirty battery surface can lead to a discharge and corrosion. It is important to avoid spilling oil or grease onto the top of the battery.

Keep your battery charged

Under-charged or under-used batteries will slowly go flat over time which will reduce the life of your battery. This happens most often in watercraft through the winter months or vehicles left unused for long periods of time. It's important to keep a battery fully charged to ensure maximum life.

How do I charge my car battery? 

Follow our tips on how to use a car battery charger:

  • If your battery has obvious wear, we recommend getting a new battery. 
  • We recommend getting advice from your local AA Battery Specialist or AA Service centre for the correct charger and charging process for your vehicle.
  • Follow the manufacturer instructions. Even if you’ve charged a battery before, we recommend following the instructions again to keep everyone safe.

Once the charger is connected it can take up to 24 hours to fully charge a flat battery.

Check out our AA Service Centre for Battery Chargers.

Handle with care

For your own safety we recommend you have  your battery checked and tested by a professional.

  • Do not place metallic objects on top of the battery as this may cause the battery to short

  • Keep flames and sparks away from batteries as they contain hydrogen gas and may catch fire or explode

  • Batteries contain sulphuric acid so make sure no part of your body or anything damageable comes into contact with the acid. If this happens, use large amounts of water to neutralise and flush acid away

  • Batteries are heavy so use correct lifting procedures and if the battery has one, use the carry handle to move the battery

  • Keep children away from batteries

When to replace your car battery

Many times the first hint of a battery problem shows up during the starting process.

If the car battery is too weak to provide a sufficient voltage to the starter, you'll hear a distinctive clicking sound and the engine won't crank over. This clicking indicates that the battery is not fully charged.

AA Battery Service can perform a battery test to determine if the battery needs to be replaced. Sometimes a faulty alternator will be the culprit, but other times the test will reveal a weak battery not capable of holding a charge. This means the battery must be replaced.

What does CCA mean? 

CCA stands for Cold Cranking Amps and is the recognised industry standard for rating a battery's cranking performance. The number of plates was once used as the measure for rating batteries, however CCA is now the industry standard.

What is Amp Hour (Ah) rating? 

The Amp Hour (Ah) rating is a way of describing a battery's capacity. It describes the capacity of a battery based on a discharge period of 20 hours.

Why do some car batteries need to be registered? 

Some vehicles are equipped with Battery Management Systems (BMS) which require new batteries to be registered with the system. In most instances, AA Batteries technicians will perform this registration on applicable vehicles.

What should I do if my battery is diagnosed as flat (discharged)?  

Normal driving will not restore the battery to a reliable level of charge. Instead, it should be recharged using a suitable multistage battery charger – and allow up to 48 hours for a flat battery to recharge.

What is sulphation? 

Sulphation is the chemical reaction between the sulphuric acid and the lead plates within a battery. When a battery discharges, ‘sulphate’ crystals form on the plates, which reduces the battery’s capacity. Batteries kept in a poor state of charge will form ‘hard’ sulphation – this causes permanent damage and can void your warranty. To reduce sulphation, fully recharge the battery as soon as possible.

Winter battery care

No one likes getting up on a cold frosty morning, least of all your car. Starting your car in the cold may cause it to suffer from hard starting and excessive cranking which has a huge effect on the motor and electrical system.

The best way to avoid your car not starting in the morning is to:

  • Keep your car in the garage. 
    This will protect it from the cold. Starting will be a lot easier, putting less strain on the battery.
  • Make sure the battery is not loose.
    Vibration can cause damage to battery case and plates. Ensure terminals are cleaned regularly during every major service.
  • Ensure your battery water level is always topped up.
    If you have a 'Standard' or 'Low Maintenance' battery, you should remove the filter caps and check the water level every month. Make sure it is topped up with distilled water to just above the plates. Mop up any spillage.
  • Listen for early warning sounds.
    One of the most common signs of a weak battery is slow cranking when you start the car. If this happens contact a battery specialist.
  • Check the age of your battery.
    Older car batteries are less likely to start your car in the winter. If your battery is more than three years old it may need replacing.