How Long Can a Car Battery Sit Unused?

Your car battery is essential for getting your car started, which means it’s integral to your day if you rely on yours to get anywhere – be it commuting to work or doing the school run. This year, more than ever, people have been finding that their cars won’t start due to a flat battery. It’s both frustrating and inconvenient.

checking car battery

This month, to help you understand your car battery better, we’ll talk you through how long they can sit unused, what their lifespan is and how you can look after your battery so that it doesn’t go flat. Here’s our expert advice from Auto Exhausts & Tyres:

How long can a car battery sit unused?

This is a common question for many people, especially during times when we’re not using cars as much to travel. A lot can depend on what condition your car battery is in. If you know your car battery is relatively new and has been kept in good condition, it can probably sit unused for about two weeks before it goes flat.

If you’ve left your car unused for over two weeks, it’s quite likely you’ll need professional assistance. Keep in mind also that if your battery has died, your brakes might also have suffered some corrosion if they’ve been wet for an extended period without use.

How long does a car battery last?

Once again, there are many things which can impact this. Typically, however, you can reasonably expect a car battery to last about 5 years. This is the average, so you might get more or less from your battery, it all depends on how much you use your car, how often you have maintenance and checks on it, how well your electrical system works and the conditions you subject the car to. 

How can I prevent my car battery from going flat?

A battery can go flat for a number of reasons, usually because it hasn’t been used for two weeks or because you’ve accidentally left something electrical running for long periods without the engine being on – think headlights or radio. Here are some easy things to do to keep your battery from going flat:

  • Use your car once a week – short, 15-minute journeys help to add a little charge back to the battery, simply sitting with the engine on won’t do the trick.
  • Get a trickle charger – this is a small unit which you can use to put a small amount of charge back into your car battery, just make sure you get the right type of charger for your vehicle.
  • Make sure you don’t leave a dashcam plugged in – this can drain your car battery if you’re not using your car on a regular basis
  • Make sure you turn your lights off when not driving – most cars now make a noise if you open your car door with the lights still on, helping you to avoid this.


A great way to find out whether your battery is in good health is to have it tested by a professional mechanic. At Auto Exhausts & Tyres, we offer battery testing as well as replacement batteries if yours is on its last legs. So whether you’ve got an old vehicle or you just haven’t been driving as much during the pandemic, we’re on hand to help you with your car battery in Lincoln.

Simply contact us today and we’ll help to get you booked in for battery testing or for fitting a new battery.