How long do car batteries last?
Batteries are the heart of every car, providing the power that keeps the engine ticking over. As much as we’d love them to last forever, they have a finite lifespan, and you might find yourself in need of a replacement at some point.
In this article, we take a look at some of the frequently asked questions surrounding the lifespan of car batteries so that you know what to expect and when it might be time to invest in a new one.
So, how long does a car battery last?
This question doesn’t have an easy answer, but it’s generally recognised that most car batteries last between 3 and 5 years.
There are several factors that can affect a car battery lifespan including temperature extremes, taking regular short trips, long periods of inactivity, vibrations from rough journeys and the number of electronic devices like sat navs and smartphones that join you on your drives.
All of these have the potential to put an additional strain on your battery and disrupt the chemical reaction inside that generates a charge.
How long can a car battery last without the engine on?
This will vary from one vehicle to another and depends on factors like vehicle type, battery type, battery age and temperature conditions.
It’s also influenced by the level of power that continues to be drained from your battery when your engine has been turned off (which is known as the ‘parasitic drain’). Most cars experience a parasitic drain of 20-50mA when they’re parked and not in use.
As an example, let’s assume that you have a fully charged 70Ah starter battery installed in your car and your parasitic drain is about 50mA. This would give you roughly 60 days of discharge before the battery is completely flat (10.5V).
How long does an electric car battery last?
Electric car batteries are a little different from fuel car batteries as electric cars rely heavily on their batteries to take you from one place to another, while fuel cars rely on petrol or diesel.
Just like batteries in smartphones and computers, an electric car battery is made of lithium-ion which means they can degrade over time. Other factors such as extreme cold or hot temperatures, overcharging or using the battery’s minimum capacity can also impact the lifespan of the battery.
Having said that, an electric car battery will still be providing at least 70 per cent of its capacity even after 200,000, suggesting that they should last for 10 years on average.
What happens when a battery degrades?
When a battery degrades, it becomes unable to supply enough capacity for its intended application and/or the cranking current to turn over an engine. The main causes of degradation in lead-acid batteries are corrosion, active material loss (where the active lead on the plates depletes) and sulphation.
While all of these processes occur naturally as part of the chemistry within lead-acid batteries, they’re often amplified by service-related issues – which is what ultimately leads to a reduced lifespan for your battery (these issues include things like deep cycling, overcharging, over-discharging and poor storage practices).
What are the weak car battery warning signs?
There are a few signs to watch out for if you think your car battery might be heading towards the end of its life. First is the most obvious one: the battery warning light on your dashboard. If that’s illuminated, then your car’s detected an issue of some kind and it’s time to get it checked.
If your engine struggles to start – particularly if it’s not a cold day, where the weather could be affecting your battery – then this could indicate a potential problem or a weakening battery.
Finally, if you’re able to start your car but your electronic systems and features seem to struggle then this could be linked to battery weakness. The best way to check this is to switch your headlights on after you’ve just got the engine going and check the quality of your beams. Overly dim headlights can be a sign that your battery is on the way out.
Common car battery problems
Here are some of the common car battery problems that drivers face. For further advice on car battery issues, check out our expert advice on car battery problems.
- Sulfation is caused when the battery is deprived of full charge
- Corrosion or damage to the positive and negative terminals
- Broken internal connection due to corrosion
- Low fluid level
How to change your car battery?
Changing a car battery is usually a very mechanical job. Therefore, it’s best to get your battery changed by a specialist. Here at Halfords, we offer a wide variety of battery-related products and services.
Products
- Car batteries: We stock batteries from leading brands including Yuasa. Simply enter your vehicle registration number online to find the best options for your car.
- Battery chargers: Our battery chargers like Halfords Automatic Battery Chargers will help to get your battery back up to full charge again.
- Jump leads and jump starters: Our range of jump leads and jump starters is ideal if you need a helping hand to get your car started.
Services
- Free Battery Health Check: One of our expert technicians will thoroughly check your battery’s key health indicators in this free check.
- Car Battery Fitting Service: Our car battery fitting service is available at Halfords stores and autocentres nationwide. Just choose the battery you want online and then select your preferred fitting option during the checkout process.
- Mobile fitting service: Our mobile technicians can come directly to your home or workplace and carry out battery diagnostics and battery replacements, as well as a range of other services. Simply book an appointment online and choose a date that suits you.
How do car battery warranties work?
All car batteries sold by Halfords come with a 3-year, 4-year or 5-year warranty and the specific length for your chosen battery will be printed on a label on the battery itself.
Battery guarantees cover any manufacturing defects that arise within the guarantee period and aren’t transferable between vehicles.
In the unlikely event that you experience a problem with a battery you purchase from Halfords, simply follow the below steps:
- Return the battery to us along with proof of purchase (unfortunately we’re unable to offer a replacement battery without a dated proof of purchase).
- We’ll then carry out a complete health check on the battery, which will indicate if there’s a fault (the results of this check are final).
- If the battery is found to be faulty, we’ll be happy to replace it for you.
Our warranties don’t cover any problems that aren’t the result of a manufacturing defect. This includes the following:
- Sulphation (this can occur when your car isn’t driven for extended periods).
- Deep cycling (this can occur when your car’s engine is started frequently or electrical components are left on for extended periods between journeys).
- Overcharging (this is usually caused by a fault in the vehicle’s charging system).
- Physical damage.
- Incorrect application (when the incorrect battery type has been used).
- Wear and tear caused by misuse.