A Guide to Replacing Your Car Battery

 

Whether you're driving a rugged 4x4, a reliable daily, or a high-performance ride, knowing how to replace a car battery is essential to avoid getting stranded. In fact, dead batteries were responsible for 43% of roadside breakdowns in 2021 — making this simple maintenance task more important than ever.

In this guide, we’ll cover how to tell if your battery’s on the way out, how to choose the right one, how to replace it, and what to do with your old battery.

How Long Does a Car Battery Last?

In Australia, most car batteries last between 3 and 5 years, though this depends on how and where you drive. Short trips can wear them out faster, while extreme heat or cold also shortens their lifespan. Regular maintenance helps, as does avoiding unnecessary electrical load from aftermarket accessories. If your battery is over four years old, it’s worth getting it tested or replaced before it fails unexpectedly.

How To Know When a Car Battery Needs To Be Replaced

Common symptoms of a failing battery include a slow engine crank, where the engine takes longer to start, or dimming lights, such as headlights or interior lights fading, especially while idling. 

Many cars also have a battery warning light on the dashboard to signal an issue. If your battery is over 3-5 years old, it may be time to test or replace it. Other signs include electrical issues like inconsistent power to windows, radio, or A/C, and visible corrosion or swelling on the battery case or terminals, which indicate a serious problem.

Which Is the Right Battery for My Car

To choose the right battery for your vehicle, start by checking your owner’s manual or using a battery fitment guide to find the correct size, terminal type, and specifications. 

Pay close attention to the Cold Cranking Amps (CCA) and Reserve Capacity (RC), especially if you’re in a colder climate or running a high-performance setup. 

For long-lasting performance and reliability, we recommend the trusted Century brand batteries. Most importantly, always ensure the battery you choose is suited to your vehicle’s make, model, and engine type.

Understanding Car Battery Ratings and Numbers

CCA (Cold Cranking Amps) - Indicates how well the battery can start your car in cold weather
RC (Reserve Capacity) - Measures how long the battery can run essentials if the alternator fails
AH (Amp Hours) - Common in deep-cycle or dual-purpose batteries, shows overall energy storage
Date Code - Tells you when the battery was made — aim for fresh stock less than 6 months old

How Much Does a Car Battery Cost?

On average, you can expect to pay between $100 and $200 for passenger vehicles, while 4WDs and performance cars may require batteries in the $200 to $300+ range. It’s always worth investing in a reliable, high-quality brand with solid warranty coverage. At Superspares, we stock a wide selection of premium 12v car batteries with fast delivery across Australia.

How to Change a Car Battery

Replacing a car battery is a straightforward DIY job with the right tools and some basic safety steps. Here’s how:

Materials and Tools:

• New car battery (matched to your vehicle)
• Wrench or socket set
• Battery terminal cleaner
• Terminal protection spray
• Safety gloves and goggles

Steps:

1. Park Safely and Power Down

Turn off the engine, switch off all electrical accessories (like lights and radio), and remove the key from the ignition. Make sure your car is parked on flat ground with the handbrake on. If your car has an automatic transmission, set it to "Park"; if it's manual, leave it in gear. 

Safety first — always.

2. Locate the Battery

Pop the bonnet and look for the battery. In most cars, it’s on one side of the engine bay, but some models hide it under a plastic cover or stash it in the boot or under a rear seat. If you're unsure, your owner’s manual will show you exactly where to look. If there’s a cover, gently unclip or unscrew it.

3. Disconnect the Terminals

Always remove the negative (-) terminal first — this reduces the risk of shorting anything out. Use your wrench or socket set to loosen the clamp and wiggle it off. If it’s stuck, try gently twisting the clamp back and forth — don’t force it with a screwdriver, as that can crack it. 

Once off, do the same for the positive (+) terminal.

4. Remove the Battery

Remove the hold-down bracket securing the battery in place. These can be a bit fiddly, especially in tight engine bays. Once loose, lift the battery straight up and out using both hands — it’s heavier than it looks. Try not to tilt it, especially if you’re handling an older lead-acid battery that might leak.

5. Inspect and Clean the Battery Tray and Terminals

Before dropping in the new battery, take a moment to clean the area. Look for rust or white powdery corrosion. A wire brush or terminal cleaner will do the job. If there’s heavy corrosion, mix a small amount of baking soda with water and scrub carefully, then dry the area completely. This helps ensure a solid connection.

6. Install the New Battery

Place the new battery into the tray in the same direction as the old one — terminals in the correct position is crucial. Some people get caught out by reversing the orientation. Secure the hold-down bracket tightly so the battery doesn’t move while driving.

7. Reconnect the Terminals

This time, connect the positive (+) terminal first, then the negative (-). Tighten the clamps just enough to hold firm — overtightening can damage the terminals or strip the bolt threads. If the clamps don’t seem to grip well, double-check for dirt or corrosion you may have missed.

8. Test the System

Start the car and check that all systems are working — headlights, radio, A/C, and the instrument cluster. Make sure the battery warning light on the dash isn’t lit. If the car hesitates to start or the warning light stays on, double-check your connections.

How Do I Dispose of My Old Battery?

Never throw a car battery in the bin — it contains lead and acid that are hazardous to the environment. If you're unsure where to dispose of car batteries, the best option is to return them to a local auto parts store or certified battery recycling centre. Many retailers, including Superspares partners, accept used batteries for proper disposal. In some cases, you might even receive a small discount or credit for recycling your old battery.

Why Recycle? The Benefits of Doing It Right

• Protects the environment – Prevents hazardous waste entering landfill
• Recovers valuable materials – Lead, plastic, and acid can be reused
• Supports sustainability – Helps reduce the demand for raw materials
• Keeps local communities safe – Prevents contamination in waterways and soil

Stay Ahead of Battery Trouble with Superspares

Dead batteries are one of the most common (and frustrating) reasons for being stranded. Staying on top of replacement timelines and recognising the signs of battery wear can save you time, money, and stress.

Check your battery regularly, replace it with the right one, and recycle the old one responsibly. Superspares is your trusted auto parts online store, offering quality products, expert advice, and fast delivery across Australia.