Car Battery Lifespans Explained

Your car’s battery is essential for getting from A to Z, and it generally runs so smoothly that it’s easy to forget about this part of your vehicle altogether.

However, if you have had your battery for a while, or if you have recently purchased a second-hand car, you may be wondering how much life is left in it.

How long does a car battery last? It’s generally around three to five years, and the reason this answer is so broad is that it depends on the type of battery, the way you operate your car and the conditions it is kept in.

Find out what shortens battery life, how age and climate play a role, and how to spot the warning signs of a battery that needs replacing before you end up stranded.

What shortens the life of a car battery?

Heat is one of the biggest factors that determines how long a battery lasts. Your car battery relies on a chemical reaction to help make your car run efficiently. Adding high temperatures to that environment can cause the battery to become less effective over time, and this can also cause internal corrosion. Once a battery loses its capacity, it cannot be fully restored. Therefore, long, hot Australian summers put every car battery’s lifespan at risk.

Your driving habits are also important. Each time you start your car, it drains your battery, and while short trips might be easy on other parts of your vehicle, they don’t give the alternator enough time to recharge the battery after each start.

Another factor is leaving a car unused for weeks, which slowly drains the battery’s charge.

Letting your battery go flat also takes its toll. This can happen when headlights or accessories are left on by mistake, or when an electrical fault keeps drawing power after the car is switched off. Sometimes, you might not even notice an interior light left on, but if it keeps happening to the point where your car won’t start, it’s not good for your battery.

The following may also shorten your battery life:

• A faulty alternator might cause a battery to be overcharged or undercharged.
• Loose or corroded terminals interfere with battery performance.
• A poorly fitted battery vibrates and suffers damage over time.

Is it true that a car battery has a fixed lifespan?

Car batteries are generally reliable and usable within a particular window of time. There is no single, defining number for how long they last; rather, it’s a range. Their lifespan is often 3-5 years and the exact number within this range depends on how and where the car is used, and the quality of the battery to begin with.

Two similar batteries can have quite different lifespans. For example, one may be fitted to a car that spends a lot of time in a hot driveway and only does short trips to the shops and back. In this case, it may only last for three years. The same battery in a car that is driven regularly and kept out of direct sunlight in a garage might last five years or more.

Your battery’s age only tells part of the story about its lifespan. A three-year-old battery in tough conditions may already be on borrowed time, while a well-looked-after one of the same age can work really well.

Rather than waiting for a firm expiry date, it’s great to keep an eye on how your car battery is performing. A battery health check from the NRMA gives you an idea of its condition and how much life is likely left.

How long does a car battery last?

It’s likely that you’ll have your car battery for between three and five years. As your car uses it to start the engine or power the dashboard lights, the battery slowly loses the ability to hold a full charge. This builds up over time until there is not enough charge to power the engine.

Here are some signs that your battery might need some attention:

• Your engine may turn over slowly when you start your car.
• The headlights may start to dim or flicker.
• A clicking sound as you turn the key (or hit the push-to-start).
• A battery warning light on the dashboard.
• Using a jump start more than once (this hints that the battery is on its way out).

Batteries may also fail unexpectedly, often during harsh weather or when an extra demand exacerbates an existing weakness like internal degradation.

If your battery is more than three years old or you think it is showing signs of being close to the end of its life, it is worth having it tested before it leaves you stranded. Don’t forget that you can book a free battery health check if you are an NRMA member.

How long do car batteries last in Australia?

Australian car batteries last as long as any other batteries in theory, but climate can be a factor in their lifespan. Being left in the sun somewhere hot can shave months off your car battery's lifespan, which is why parking in a garage or in the shade is recommended when possible.

If you’re in parts of the country that get very cold like the Snowy Mountains, be aware that this can also affect your battery life if your vehicle is left outside in near or below-zero temperatures.

The NRMA replaces car batteries across NSW and the ACT, at home, work or wherever you happen to be.

Does cold weather affect car batteries?

Definitely, however, cold only reveals car battery damage at the worst possible moment. Unlike heat, which can shorten a battery’s lifespan, cold weather tends to expose weaknesses that are already there.

In cold conditions, the chemical reactions inside a battery slow down, delivering less power just as the engine needs more to turn. The resulting thicker and colder engine oil also adds to the effort. Therefore, a battery that worked fine all summer can struggle on the first frosty morning. You might have noticed how your car is a bit slower to start during winter, often because the chemical reaction is slower.

When there’s a weakness in your battery’s capacity, especially during warmer months, a cold snap often makes it obvious as the charge is reduced. Batteries carry a cold cranking amps rating (CCA) to show how much starting power they can deliver in low temperatures.

If your battery is a few years old heading into winter, running a car battery health test can save you from ending up with a car that won’t start on a freezing morning. The good news is that an NRMA Patrol can come to you, and you can even book ahead (just call 1300 726 751).

Read more about how cold weather affects your car battery.

How long does a mobile car battery replacement take?

A mobile battery replacement takes about 20 minutes once the problem is diagnosed. Once your friendly NRMA Patrol arrives, testing the battery takes under ten minutes, and if a replacement is required, it is usually done within twenty to thirty minutes. Most cars are back on the road with one callout, with a warranty to cover you if anything goes wrong.

Some cars may require a system reprogramming or reset after a battery replacement, but your NRMA specialist will let you know. 

Some cars need extra care as the batteries might be under a seat, in the boot or behind panels that need more time to reach. This can add a few extra minutes to the replacement time. 

With the NRMA, you can book a time online that suits you, or call for help if you have broken down and need to get moving again. Our services even include removing and recycling your old battery. 

Stay a step ahead of a flat car battery

A battery that fails without warning can ruin your whole day, but a little attention and planning go a long way. Finding out your battery age and having it tested once it passes three years will help you avoid the frustration of a car that suddenly won’t start.

If you are a member of the NRMA, you can request a free battery health check any time. If not, joining brings peace of mind and reliable battery replacement and checks anywhere in NSW or the ACT. You can sign up on the spot if you’re stuck and need a hand with your car battery.

Book a car battery check online or call 1300 571 746 to arrange a check or replacement for your vehicle.