How Long Can A Car Battery Sit Unused?

Will your car battery still work if you leave your car in the driveway for a few months? Maybe. WeBuyJunkCarsFast explains what can go wrong if you leave your car battery alone for a few months, and what you can do to preserve it instead.

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There’s countless reasons why someone might stop driving a vehicle — moving to a transit-friendly environment, working from home, or getting a newer car that is more reliable, as a few examples.

In such circumstances, you may be compelled to just let your vehicle sit unused. But did you know that leaving your car without starting it can cause your car battery to fail?

Luckily there are ways for you to prevent your car battery from dying when not using your car. Read on to discover why your car battery may be dying, how often you should start your car, and what to do when your battery fails.

How Long Can You Leave a Car Without Starting It?

Generally, you’ve got about two weeks before your car battery goes bad from sitting too long. Of course, the exact time will depend on different factors.

For example, a brand new battery may be able to sit for roughly 3 months without any lasting damage. However, an older battery is more susceptible to “going flat” after sitting for a few days if it's not in good condition.

Sitting batteries begin to lose their charge and you might find yourself jumpstarting a dead battery instead of jumping into bed after a long vacation!

As our cars get more technologically advanced, they are built with more gadgets and computer technology than previous makes and models.

The newest models are manufactured to have technology constantly monitoring your car’s systems. All of these systems draw their power from your car battery. Without regular use, the battery doesn’t have a chance to recharge.

How To Keep A Car Battery From Dying When Not in Use

The simplest thing you can do to keep your car battery from dying is to make sure you start it at least once a week and drive for at least 10 miles before turning it back off. Start your car and take it for a quick 10-15 minute spin at least once a week.

If you know your car is going to be left idle for an extended period of time and you won’t have any access to it, it’s best to disconnect the battery completely.

If you store a detached battery properly, it has a chance to last up to half a year. It will still need charging, but not nearly as often when it’s still attached to your vehicle. Delivering a charge once every four months should be enough to keep the battery viable.

Here are some easy methods on how to prevent car battery drain when not in use:

  • Once a Week Drives – taking short, approximately 15 minute drives once a week will keep your battery from going flat from disuse.
  • Trickle Charger – small portable units you can use to place a small amount of charge back into your car battery.
  • Unplug Your Dashcam – a dashcam can continuously drain your battery, so unplugging it can help preserve your car’s battery.
  • Turn Your Lights Off – most cars will automatically turn off your lights when you leave your vehicle or make a noise if you haven’t turned them off. Make sure you turn your lights off to ensure battery preservation.

What Causes Car Batteries to Fail?

  • Time - Father Time is undefeated and car batteries are no exception to that. Eventually your battery will no longer hold any charge, typically within three to five years of use. Batteries that sit unused are even less likely to start your car up.
  • Corrosion - A natural part of your batteries life cycle that can be quite a thorn in your side if you don’t keep track of it.
  • Cold Weather - Even mildly cold weather impacts your car battery. At 32 degrees, your battery is 35% weaker and at 0 degrees it plummets to 60% weaker than normal.

There are other scenarios that impact your car battery’s performance, like bad alternators, broken fuses, or headlights that are left on.

Ultimately, the best practice is to prepare yourself to deal with a dead battery. Jumper cables, portable jumpstart units, etc. all serve the purpose of cranking up that battery that may have sat for one too many weeks.

Now, if you’ve got yourself a hybrid vehicle, then a dead battery may present a more difficult scenario.

Hybrid batteries face many of the same issues batteries in full-combustion engine vehicles do when left idle for long periods of time. They differ, however, in that replacement hybrid batteries can cost thousands of dollars.

But what do you do when your car and its battery finally bite the big one?

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What Can You Do With A Car With A Damaged Battery?

In the event that you find yourself having let your battery sit and it’s now completely dead, no sweat.

Contact us here at WeBuyJunkCarsFast and let us do exactly what it says in our name. Our customer service representatives will kick back a quote for your vehicle within 90 seconds.

Should you like the offer, we can then connect you to one of our local partners. They can retrieve the vehicle, absolutely free of charge, while also putting the quoted amount directly into your hands.

We remove the hassle of removing your dead vehicle, making your life a little easier!

How Often Should I Start My Car To Keep The Battery Charged?

Start your car once a week and take it on a short, 15 minute drive in order to preserve the integrity of the battery.

Why Does My Car Battery Die After Sitting For A Few Days?

If your car battery is dying after only sitting for a few days then the battery likely has an issue that has compromised its efficiency. Check for corrosion, but age may just be the biggest factor and you’ll need to get a new battery.

What Happens If I Don’t Start My Car For A Month?

If you don’t start your car for a month, you risk letting your battery suffer from being unused. To avoid that, start your car and drive it for 15 minutes once a week, just to keep all of the fluids from going stale and the charge from depleting.

Can You Let A Car Sit For 6 Months?

You can, however it’s not in your best interest. Over those 6 months, your battery will lose its charge, pests may move into your vehicle, and Mother Nature will have her way with your car.

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