How long does a car battery last?

If you’re evaluating your car’s maintenance requirements and wondering, “How long does a car battery last?” you might be surprised to find a range of answers.

Car batteries can last anywhere from three to 20 years. This is because the life of a car battery depends on several factors, including your car’s engine type (hybrid and electric cars use different batteries from pure-fuel ones), how you drive your car, how well you care for and maintain it, and certain environmental factors.

Let’s dive into these points in a bit more detail.

How long does a fuel-engine car’s battery last?

Batteries for diesel and petrol engine cars usually last three to five years, subject to maintenance and other factors.

When you buy a car, the manufacturer’s warranty may only offer full coverage for a limited period of time (it’s worth checking how long beforehand). If you purchase a new car battery from a supplier, they’ll usually offer a warranty ranging from one to five years.

How long does a battery last in an electric car?

Electric vehicles (EVs) haven’t been on the roads long enough for us to know for sure how long their batteries will last. However, recent data indicates that EV batteries are set to last longer than expected, possibly over 20 years.

Most EV manufacturers in the UK offer battery warranties of eight to 10 years or 100,000 miles, whichever comes first. Research by Geotab, a Canadian multinational that supplies telematics hardware and software for motor use, revealed that EV batteries degrade by around 1.8% annually on average. Top-performing EVs boast a degradation of just 1% per year.

The general consensus is that EV batteries don’t need replacing until they drop to 70% of their original capacity or lower. This means, assuming an average degradation rate of 1.8% per year, that the 20-year (or more) projection is likely spot on.

6 Main factors affecting car battery life

Understanding the factors impacting your car battery’s lifespan can help you estimate how long it’ll last and take steps to keep it in good shape. Here’s what you need to know:

• Material and size: Car batteries are manufactured from different materials, such as:
  
  
  • Lead-acid batteries are some of the most common types used in cars. They’re recyclable and relatively inexpensive, offer reliable performance, and store a considerable amount of energy. These batteries usually last three to five years.
    
    
  • Lithium-ion batteries, used mainly in EVs and in some hybrid cars, have an expected lifespan of around eight to 20 years.
    
    
• Climate and temperature: Car batteries work best in moderate climates. Temperatures that are too hot can cause car batteries to drain and damage them in the long term. On the other hand, extremely cold weather conditions slow batteries’ electrochemical reactions, reducing their power output and putting strain on them.
  
  
• How the car is driven: For internal combustion engine (ICE) cars (i.e., petrol and diesel engines), frequent short trips can hurt the battery’s lifespan. This is because ICE car batteries recharge themselves as you drive thanks to an alternator. Starting the car takes up a fair bit of power, but short trips don’t let the car run long enough for the battery to recharge fully.
  
  
• Maintenance and care: Regular maintenance practices, including cleaning the battery terminals and getting the battery serviced annually, can help it last longer.
  
  
• Storage and charge: Leaving a car idle for a prolonged period of time isn’t good for it.
  
  In an EV’s case, doing so can particularly hurt its battery’s lifespan. Similarly, regularly using fast charging, or letting the battery drain to 0% and charging it to 100%, can wear it down eventually. While doing any of these actions on occasion won’t seriously impact your car’s battery health, they can collectively harm it over time.
  
  
• Age: How long your car battery will last largely depends on how old it is. If you’ve had your car for a while, or have bought a second-hand one with an old battery, it likely won’t have as long a life as the battery of a new car.

How do I know when my car needs a new battery?

Your car’s battery could be giving you trouble for different reasons, such as cold weather, leakage, or corrosion. The cause and severity of the problem really determine the kind of work you’ll need, such as a DIY fix, servicing from a mechanic, or a full-on battery replacement.

Here are some signs that indicate problems with a car’s battery:

• Battery warning light: Many modern cars have this light on the dashboard. It’s one of the most obvious indicators that the battery isn’t working optimally.
• Problems with starting your car: If your car takes longer to start up than usual, your battery might be giving out. And if there’s a fast, clicking sound when you try to start the engine, but there’s no ignition, the battery could be dead or on its last legs.
• Dim headlights: If you suspect your car battery might be weakening, one of the simplest ways to check is to turn your headlights on while the engine is off. If the headlights aren’t at their usual strength, your battery likely isn’t performing as it should.
• Corrosion on the battery terminals: If you open your car’s hood and find a white or blueish, powder-like build-up around your battery terminals, it could be corrosion. This can harm electrical flow. Corrosion can occur for several reasons, including general wear and tear, or leakage from overfilling the battery with fluid.

If you suspect that your car’s battery might need to be serviced or replaced, it’s best to consult a mechanic as soon as possible.

Best practices for keeping your car battery in good shape

Looking to get the most out of your car battery? Here are some tips to help extend its lifespan.

For diesel or petrol engine cars

• Be mindful of how you drive the car: Since your battery recharges as the car is driven, it’s best to avoid only making short trips, as doing so won’t give the alternator enough time to charge the battery. If you can manage it, it’s good practice to fit in a long drive (two hours or more) every few weeks.
• Keep an eye on the battery fluid: Car batteries include a liquid electrolyte mix (usually water and sulfuric acid) between the positive and negative terminals. The liquid allows electric particles to travel between these terminals. However, it evaporates over time, so it’s important to replenish it. Additionally, overfilling the battery with fluid can dilute the electrolyte mix, so be careful of doing so.
• Avoid using the battery power when your car is off: When your car’s engine is off, using features that require power, such as the AC/heater or radio, will drain the battery without recharging it.
• Keep the battery terminals clean: If grime, dust, or corrosion accumulates, you can do a safe DIY cleaning or get it professionally cleaned.
• Get the car battery serviced: It’s generally best to get your battery checked, and potentially serviced, at least once a year.
• Protect your car from extreme temperatures. While you don’t typically need to worry about extreme heat in the UK (except for the odd heat wave), extreme cold can be bad for both EV and combustion engine car batteries. So in the colder months, try to keep your car parked in the garage for protection. Learn more about ways to protect your car from cold weather.

For electric vehicles

EV batteries are more integral to the car’s performance and far more expensive to replace, meaning it’s that much more important to take care of them. Here are some of the best practices to follow:

• Avoid full charge and full depletion: Letting your car battery hit 0% or charging it to 100% can hurt its lifespan. In general, most car manufacturers recommend keeping your EV battery charged between 20 and 80%.
  Long trips are typically the only time when you might need to charge the battery fully. In these cases, too, though, it’s better for the battery’s health to keep it between 20 and 80%, and stop to charge it along the way.
• Avoid fast charging: Also known as rapid charging or supercharging, fast charging can be convenient in a pinch, but it’s not good for your battery’s overall health. So unless you’re on a tight schedule and need to charge your car immediately, it’s best to stick with normal charging speeds.
• Try to use your EV regularly: Just like with petrol or diesel engine cars, leaving an EV idle for too long isn’t good for its battery. So it’s good to take it out regularly if you can.

Summary: How long does a car battery last?

There’s no set answer for how long a car’s battery will last. Its lifespan depends on various factors, including the materials it’s made from, how you drive the car, your local climate, and regular maintenance.

In general, you can expect a petrol or diesel engine car’s battery to last around three to five years. Your car battery should last four years or more if you take care of it by getting it serviced annually, keeping it clean, and avoiding too many short trips.

Although EVs haven’t been on the road long enough for anyone to be sure about their battery’s lifespan, recent data seems promising. At the very least, your EV’s battery should be covered for the first 100,000 miles or eight to 10 years by a warranty. After that, with a bit of luck and the right care, you might get another 10 years or more out of it.

Battery failures aren’t the only problem that cars can run into. Howden Insurance offers comprehensive, personalised car cover, keeping you covered for theft, vandalism, fire, natural disasters and more. Contact us for a quote today.

Also read:

• How to charge a car battery
• Car insurance for non-UK residents: What to know
• Your guide to low-mileage car insurance
• CAR INSURANCE GUIDES