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How Long Can a Car Battery Sit Unused? What Factors Into It?
Pete Ortiz
Last updated:
A car battery is an essential component of every vehicle, and it represents the heart of the car. If you ever wondered how long can a car battery sit unused, we’ve got the answer. If unused, a car battery will usually not last longer than two weeks. That happens because the battery doesn’t have time to recharge when you’re not using your car.
In this article, we will talk about the importance of car batteries, their storage, and other crucial things you should pay attention to when it comes to car batteries.
What causes a car battery to fail?
There are a couple of different reasons that can cause your car battery to fail, other than leaving it unused. Check out the most frequent ones below.
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1. Time
Like any other battery, car batteries can wear out and stop working. Their usual lifespan is anywhere from 3 to 5 years. Also, time affects batteries when they are unused. The longer the battery is unused, the less it will function. As we mentioned earlier, if a car battery is unused, it cannot last longer than two weeks. That’s something you should consider if you want to prolong your car battery lifespan.
2. Corrosion
Another common reason for car battery failure is corrosion at the connectors. If they are gunked up, the alternator in your car might not recharge your battery as it’s supposed to, which will lead to the battery dying. If you notice any signs of green/blue growths at the battery terminals, it means your batteries have corroded. If corrosion has just begun and there’s not much of it, you should be able to wipe it with a dry rag. If that doesn’t work, you can try cleaning it off with a stiff wire brush.
3. Weather
Car batteries do not react well to cold weather, so that could be another reason causing your car battery to fail. If you live in colder areas, you cannot do much about this issue. Keeping your car in the garage or a closed area might help, but the battery can still fail. For these situations, it’s always good to have a replacement battery nearby, just in case something happens. It would be helpful to keep an eye on symptoms of malfunctioning in the battery.
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4. Human errors
As you probably know, errors that we make can significantly impact battery failures. If you forget to turn off the headlights or charge too many devices inside a car, all of those situations we all occasionally do can damage our car batteries. Always ensure that everything is shut down and give your battery a break to last for years.
5. Electronic drain
One of the most common electronic issues that can cause a car battery to die is the alternator. Of course, that doesn’t apply to suitable alternators, but if your alternator is malfunctioning, your battery will most likely die quickly. That’s because the battery needs the alternator to recharge.
So, if the alternator is not doing its job, you can say goodbye to your vehicle battery. Another frequent electrical issue can be a broken fuse. If you suspect anything weird is happening to your car that’s electric-wise, it’s best to visit a mechanic to check what’s happening.
How to store a car battery?
You should store a vehicle battery at a full charge to prevent deterioration and possible damage. That will help it hold the charge better and reduce wear in the battery. If you have a car battery you will not use for some time, you should adequately store it until the next time you need it. Ensure that there is no damage to the battery, and clean any corrosion.
You should store it in a well-ventilated, dry area. Avoid places that can get too hot or cold, making the battery discharge faster than usual. Once you store it, don’t forget to check it once in a while and recharge it if it’s under around 70%.
The best way to prevent the car battery from going flat is to recharge it when needed. You can turn on your car once a week for 5 to 10 minutes to ensure that the battery will get charged enough.
If you cannot charge the battery weekly by turning on the vehicle, it would be best to completely disconnect it from the car and store it in a secure area. It will also need occasional charging, but it can last for about 6 months. There are great trickle chargers that can help you get a small amount of charge to the battery, too.
What to do if your battery is dead?
If your battery is dead, you can try to jump-start your vehicle. That can get the car going if the battery and the vehicle are in good condition. Unfortunately, if that doesn’t work, that means it’s time to buy a new car battery. We already mentioned that bad alternators could cause battery failure, so it’s always good to check the condition of your vehicle at a trusted mechanic.
Of course, try to keep your battery in shape to have a longer lifespan.
How to replace a car battery?
Replacing a car battery is not a difficult job, but there are some steps you will need to follow. Below you can find a mini-guide for how to replace a car battery.
Image Credit: BruceEmmerling, Pixabay
1. Remove cables
When deciding to replace your car battery, the first step is to remove the cables. Loosen up the positive cables first, followed by the negative, or ground cables.
2. Remove the screws and battery
Once you remove the cables, you should remove the screws and the battery. For this step, it’s best to wear protective rubber gloves. Keep the battery screws as you need to reuse them.
3. Inspect the tray
The tray under the battery is also prone to corrosion and can get dirty. You should inspect it and clean it if needed. That will help your new battery to function without issues.
4. Position the new battery
Take the new battery and put it in its place. Ensure that it’s turned the correct way and that it’s firmly set where it needs to be.
5. Replace screws
To keep the battery secured and in place, you should replace the screws and tighten them to keep everything together.
Reconnect cables using the same principle you did to remove them. You can always check a manual if you’re unsure about which cable you should connect first.
Old batteries contain particles that can be harmful to the environment. You should never throw away an old car battery into a regular trash can. Instead, look for recycling centers that accept old vehicle batteries.
If you’re not handy, you can always reach out to a professional mechanic to replace the battery for you.
We hope that this article has helped you find out more about how long a car battery can sit unused and other essential information about car batteries every car owner should know. If you store your battery and do not plan to use it, follow all the needed rules and guidelines to preserve it and prolong its lifespan.
Pete has been working in the trades since high school, where he first developed a passion for woodworking. Over the years, he has developed a keen interest in a wide variety of DIY projects around the home. Fascinated by all sort of tools, Pete loves reading and writing about all the latest gadgets and accessories that hit the market. His other interests include astronomy, hiking, and fishing.
As the founder of House Grail, Pete's primary goal is to help consumers make educated decisions about DIY projects at home, in the garage, and in the garden.
