You may be concerned about how long your car battery can last without driving if you’re going to leave it parked for a long time.
Occasionally, we leave the car for a long time, such as abroad. We might also park our cars for a long time without using them if we have more than one. Whatever the reason, you probably know the battery won’t last forever. So, how long can a car battery last without driving?
If you’ve parked your car for a long time with the battery connected, it can drain completely in under two months, depending on the type of battery, its capacity, and other factors. Generally, better quality, newer, and higher-capacity batteries will last longer, whereas cheaper, older, and lower-capacity batteries won’t last as long and will drain quicker.
Importantly, I’ve also covered ways to make your battery last longer if you need to park your car for a long time and what to do when you’re ready to drive again.
How Long Does a Car Battery Lasts
A car battery converts chemical energy into electrical energy while the engine powers various accessories.
While not running, the battery cannot charge itself, so the charge gradually decreases. How long it takes to go from fully charged to being dead depends on the type of battery, its quality, its capacity, how old or weak it is, etc.
| Factor | Description |
|---|---|
| Quality | Better-quality batteries tend to last longer. |
| Capacity | Higher-capacity batteries have a longer lifespan. |
| Age | Older batteries tend to have a shorter lifespan. |
| Temperature | High temperatures can reduce battery lifespan. |
| Parasitic Drain | Electrical systems that draw power from the battery when the car is turned off can shorten the lifespan. |
Generally, better quality, newer, and higher-capacity batteries will last longer, whereas cheaper, older, and lower-capacity batteries won’t last as long and will drain quicker.
However, also beware of what’s called a “parasitic drain.” That’s when the car’s electrical system continues to draw power from the battery, even while the car is turned off.
Continue reading to learn about ways to help you make your car battery last longer when not driving.
How to Make a Car Battery Last Longer
Using a car regularly is the best way to make a car battery last long.
You should at least drive it for up to half an hour every week. If you can’t do that, the battery will not likely last long before draining completely.
To make a car battery last long without driving it, you can do three things to a parked car:
- Disengage the car’s security system if keeping the battery connected.
- Disconnect or completely remove the battery.
- Attach a battery maintainer to prevent the battery from discharging.
- Start the engine at least once a week and let it run for 10-30 minutes each time.
| Method | Description |
|---|---|
| Disengage the car’s security system | Turn off the security system to prevent quick battery drainage. |
| Disconnect or remove the battery | Disconnecting or removing the battery altogether can prevent battery drain. |
| Attach a battery maintainer | Use a battery maintainer to add a little charge to the battery at intervals to prevent it from discharging. |
| Start the engine | Starting the engine once a week can help the battery regain lost charge. |
Disengaging the Security System
Leaving the security system on can cause the battery to drain quickly.
You won’t benefit from the security protection by turning it off, but if you want the battery to last long, you’ll have to make this compromise. This should not be a problem if your car remains in your locked garage.
Disconnecting the Battery
You can either disconnect the battery or completely remove it from the car.
One option is to disconnect the cable altogether. Disconnect it first from the battery’s negative (ground) terminal, which is the black wire, then from the positive terminal. This will prevent battery drain, while the sequence will help avoid the risk of short-circuiting.
If you intend to leave the car parked for a long time, it’s better to completely remove the battery from the car. Keep the battery in a dry and well-ventilated environment. The temperature should ideally be within the range of 40-60°F (4-15°C).
In either case (only disconnected or completely removed), the battery will still drain over time but at a much slower rate. You may still need to recharge it when you get back.
Attaching a Battery Maintainer
Attaching a battery maintainer is a way to prolong the charge in a car battery without disconnecting, disengaging, or removing anything.
A battery maintainer adds a little charge to the battery at intervals to prevent it from discharging. But you can only make this arrangement if you can access an AC outlet nearby.
The battery maintainer will periodically check the charge and, if necessary, will top up it to maintain it, hence the name. Unlike a traditional battery charger, it doesn’t overcharge the battery, so it’s generally safe.
However, I recommend disconnecting accessories like clocks, alarms, and radios to prevent the battery from discharging quickly.
Starting the Engine
If you can at least start the car once a week, even if you don’t want to drive it, then this is another option.
As I advised earlier, try to run the engine for at least 10 to 30 minutes at around 1000 RPM while parked. Please keep it in neutral gear. This will help the battery regain lost charge.
If you don’t like the idea of consuming fuel or are low on gas, choose one of the other three options instead.
When You’re Ready to Drive Again
Checking the Battery’s Condition
If you’ve returned to drive your car after leaving it parked for a long time, you’ll need to check the battery’s condition first.
Remove the cover over the battery to expose its terminals and test the voltage across them using a voltmeter or multimeter. Connect the red probe to the battery’s positive terminal and the black probe to its negative terminal. If the voltage is at least within the range of 12.4-12.7 volts, then you’re in luck, as the battery is good to go.
| Step | Description |
|---|---|
| Remove the cover | Remove the cover over the battery to expose its terminals. |
| Test the voltage | Test the voltage across the terminals using a voltmeter or multimeter. |
| Check the voltage | Check if the voltage is within the range of 12.4-12.7 volts. |
| Recharge the battery | If the battery is dead, recharge it at home or jump-start it and drive to allow the alternator to recharge it. |
| Clean the terminals | Ensure the battery’s terminals are clean and corrosion-free before reconnecting the cable. |
Recharging a Dead Battery
If you have a dead battery because you left it connected in a parked car for a long time, you might want to know how to recharge it quickly.
Read our articles on how to do that, such as: How Long Does it Take to Change a Car Battery? You may need to charge it at home or jump-start it, then drive it to allow the alternator to recharge the battery.
Also, ensure the battery’s terminals are clean and corrosion-free before reconnecting the cable.
References
Battery maintainer. https://www.goo-net.com/pit/shop/0208665/blog/323569
Tony Hunter. How to Rebuild the Big-Block Chevrolet. CarTech. 2009. Retrieved from https://www.google.com.pk/books/edition/How_to_Rebuild_the_Big_Block_Chevrolet/5wUlgzIoWgcC?hl=en&gbpv=0
Video References
DIY Pinto. https://www.youtube.com/watch?v=d_PandQznIs
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