A dead car battery is something we all faced during the extended period of homebound COVID-19. A spike in lead acid battery prices soon after the SOPs lifted was because most car batteries died during that time without driving. Batteries are the beginning bud of a smooth functioning car, but have you ever thought about how long a car battery lasts without driving?
Typically, a car battery lasts for nearly 14 to 30 days (2 to 4 weeks) without you needing to power and start the car. However, the time varies according to battery condition, type, and other factors. It is better to start the vehicle once weekly to keep it charged when not in use.
Want to learn more about what kills a battery fast? And how to prevent your car battery from getting flat when not driving? Then read on, as this article covers all the nuts and bolts related to it.
Now, let’s tear into the details!
What Kills A Car Battery?
Nothing turns out to be more annoying than a dead car battery at the time of need. when it comes to the rapid draining of a car battery, you will find multiple factors (from corrosion buildup to a bad alternator). Following are some key factors that can kill a car battery.
- Faulty Charging
One prime factor that leads to a flat battery within no time is faulting charging. It happens due to an incorrectly working alternator.
The alternator fails to recharge the battery properly due to a worn-out tensioner.
It is the worst factor as this suddenly leads to a haywire battery without any warning sign.
- Parasitic Draining
Another factor that actively contributes to killing your car battery is the parasitic drain. Even though your car is off, the battery powers components like a security alarm, computer, sensors, clock, radio, etc.
As a result, the battery is constantly draining but not getting recharged.
- Bad Diode Alternator
We know that diodes are the central hub in alternators that convert AC into DC on which the car battery and other electrical components run.
If there is a burnt-out or bad diode alternator, it also results in rapid depletion of the battery and easy drain.
This ultimately kills the car battery.
- No Drives
Soon after we start a car, the alternator and diodes function together to recharge and replenish the car battery.
If you won’t drive the car for a long time or provide it with power, it will result in a dead car battery within no time.
- Temperature Extremity
Batteries are designed to work at an optimal temperature range in which electrochemical reactions and conversions can take place efficiently.
However, sulfate crystals start to build up at temperatures extremity like -10°C or 100°C. These crystals remain on the battery plates, thus preventing the battery from getting completely charged.
Moreover, the battery faces issues like evaporation, easy corrosion, and overcharging at high temperatures.
Similarly, at low temperatures, it has reduced capacity, thicker transmission & engine oil, an increase in load, and a significant reduction in the rate of charging.
All these factors impede electrochemical conversion. In this way, it damages the battery and decreases its lifespan.
- Loose Battery Terminals
With time, the strong battery acid reacts with battery cables, resulting in corrosion.
These corroded cables drain the battery rapidly and prevent it from getting charged.
- Human Error
This is something we all have done at least once in our life. Mostly after a hectic grind of the day or on busy schedules, we forget to close the trunk, turn off the headlights, or leave some internal component on.
As a result, the car battery remains functional the entire night and ultimately drains.
All these factors ultimately result in a dead car battery before time.
Will My Vehicle’s Battery Die If I Don’t Drive It For A Week?
If you have a new car battery, it won’t die if you keep it sitting for a week or ten days. If in case it dies, it means there is some problem with your new car battery that you need to figure out.
However, if your car battery is old and in bad condition, it can die after sitting for a week without a recharge.
The reason is that although you aren’t using the car, various internal electrical components lead to parasitic draw of current and charging (I mentioned earlier).
As a result, the battery is constantly draining. On the other hand, since you aren’t using the car, there is no external agent to replenish the loss.
All this ultimately results in a dead car battery.
Tips: Starting the car and powering the engine for nearly 15 to 20 minutes at least once or twice a week is a sound way to increase battery life. This helps the alternator keep the battery topped up and extend its lifespan.
How Do You Understand That Your Car Battery Is Dying?
Have you also not started the car for weeks and now feel worried about your car battery health? Want to know if it is in good condition or soon about to die?
Here are the most obvious tell-tale signs to help you understand whether your car battery is about to die.
- Sluggish Cranks
If your battery cranks slowly at normal temperature, it alludes to some problems with the battery.
The battery is probably draining and is soon going to die.
Similarly, if your engine cranks at normal speed but the engine fails to start, it signifies the same problem.
- Not Starting On Ignition
If your car does start when you turn the ignition key, it also means that you have a dead or nearly flat battery that needs replacement.
However, a temporary fix is to jump-start the car.
- Flickering Or No Headlights At All
Another sign of a dead car battery is a flickering headlight, a dim one, or no light in the headlights.
So, if you start the car and the headlights dim or have no light, your car battery is probably dead.
- Swollen Battery Case
A swollen, bloated battery is the most obvious indicator of a worn-out battery that needs urgent replacement. It happens when excessive hydrogen gas builds up in the battery.
Hydrogen gas is released from the battery during the charging process.
So, when you don’t charge a battery, the gas accumulates within, leading to a draining battery with a bloated, shapeless battery case.
- Corroded Terminals And Leaking Fluid
Lastly, if you observe corroded battery terminals and some oily fluid leaking from the car, your battery is in bad condition.
The terminal wires react with the battery acid and electrolyte; as a result, they get corroded and result in voltage issues.
Similarly, if you find any (rotten egg) smell coming from your car, your battery is leaking hydrogen sulfide gas and about to die.
Experts’ Recommendation: It is better to keep an eye on the voltmeter of the battery and give it an energy boost before its value drops down the limit.
How Long Should A Car Battery Last Without Driving?
It is mentioned earlier that a good-conditioned car battery can last two weeks without driving. After this, it will also deteriorate and become flat.
On the other hand, an old battery can stand for ten days or even less.
Most people think a battery is used only when the car is turned on. But that is not the truth and you have already known the reason behind this experimental logic.
Note: The alternator and diodes are forced to work even harder to power these components without getting charged.
Ultimately, the battery runs short of power, gets damaged, and dies.
About New Car Battery Last Without Driving
How long should a new car battery last without driving? A new, fully charged car battery should last 2 to 3 weeks without driving. After this, the battery starts to deteriorate slowly, and after almost 8 to 10 weeks, it completely runs out of power.
Thus, you won’t be able to start the engine and fall for the mechanic’s help.
Things To Do: If you are going for a vacation or aren’t aiming to use the car for any reason, be wise enough to remove the car battery. It will increase the battery life and prevent it from getting damaged without serving you for a reasonable time.
How Many Times Can A Car Battery Be Recharged?
How often you should recharge a car battery depends on the battery type.
However, a rule of thumb is that a battery can undergo 500 to 1500 charging cycles before dying. However, each charge needs to recover some of the charging capability.
- An electric car battery can undergo 1500 to 2000 cycles of charge.
- You can recharge Lead acid batteries at least 1000 times.
- Nickel Hydrogen Battery can be recharged more than 20,000 times with 85% efficiency.
- Deep Cycle batteries undergo around 200 to 300 charging cycles.
- Lithium Ion batteries can undergo 300 to 500 cycles of recharge.
- SLA batteries have 50 to 500 charging cycles.
How Often Should I Start My Car To Keep The Battery Charged?
It is advised to start your car once a week at least to keep the battery charged and thus prevent it from dying.
Moreover, allowing the engine to run for 15 to 30 minutes is a sounder option. It will give the engine the necessary boost to charge the battery and prevent it from getting damaged via the parasitic drain.
Warning: Don’t overcharge the battery. Else the electrolytes get hot and result in excessive gas production.
How To Keep A Car Battery From Dying When Not In Use? Or How do I Stop My Car Battery From Draining?
Now that we are well up with what makes a car battery dead while sitting, let’s find some ways to keep our car battery from dying.
- Remove The Car Battery And Store It Properly
If you aren’t aiming to have a drive soon, the best way to prevent your battery from draining is to remove it and store it in a dry place. Keep it somewhere with a temperature between 40 to 60 degrees Celsius.
- Disconnect The Negative Terminal Of The Battery
When the car isn’t in operation, the key off drain (parasitic drain) is the prime source of utilizing battery energy.
So, if you want to avoid getting into the hassle of removing the battery from the car, here comes another viable option. Open the circuit by disconnecting the negative terminal of the vehicle. As a result, the electrons won’t be able to flow, leading to no electrochemical conversion.
Now you must be thinking, why not disconnect the positive terminal?
While disconnecting the positive terminal, there is a high risk of electric slip, leading to damage to other electrical components of the vehicle.
- Disconnect The Security System Of The Car
You can also disconnect the security system of the car.
So forth, all the electric systems that drain the energy will be disconnected.
- Buy A Battery Maintainer
Another feasible option to go for is to buy a battery maintainer.
The battery maintainer charges your battery whenever it drops below the level, but it doesn’t overcharge. It automatically turns off soon after the battery becomes fully charged.
Technical tips: Make sure to buy a battery maintainer of the same voltage as that of your car battery.
When To Change A Car Battery?
No car battery lasts forever.
Like mobile phones, the car battery also deteriorates with every charge.
Generally, a car battery lasts for three years. After this lifespan, it’s better to get your battery changed.
Nevertheless, some batteries can last for 4 to 5 years too. However, their operation and safety guarantee could be more reliable.
Here are some signs to keep an eye out for and find the right time to give a new battery push to your car.
- An oddly shaped, swollen battery
- Batteries with fluid leaking out of them
- Illuminated battery light
- Slow engine crack
These signs stipulate that the car battery is on its last leg. It would be best if you get your car battery changed.
Q.1 Will a car battery recharge itself overnight?
A car battery can’t recharge itself overnight. No matter how maintained and healthy a battery is, it can never charge itself without any external source. It always needs an external powering agent to get recharged. Mostly, the alternator performs this vital role.
Q.2 Can you revive a dying car battery?
You can revive a dying car battery and bring it back into function.
A few known ways to fix and recharge a nearly flat battery are:
- Epsom salt method
- Chainsaw method
- Booster pack
- Hard Hand Cranking method
- Hot Ash method
- ASPIRIN solution
Q.3 Can a car battery die if not driven for three days?
If your battery is very old, it can deteriorate if not driven for three days. It’s better to check your multimeter to find out why your car battery drained so early.
Note: If you use a lead acid battery, there are chances of rapid oxidation that can lead to quick draining of the battery.
Q.4 Is the car battery dead after sitting for five days?
In most cases, NO!
We already discussed the dying time of an unused car battery is 2 to 4 weeks. However, if your car battery died after sitting for only five days, here are some possible reasons:
- Poor conditioned battery
- Parasitic draining
- Connections are corroded
- Temperature extremes
- The Dome of headlights left on
Q.5 Can a car battery go bad after one year?
Car batteries have a finite time of 3 to 5 years, after which it drains and dies.
However, if the battery isn’t used and maintained properly, it can go bad within one year.
Mostly it is because of the casual drains and no recharge by the alternator.
Q.6 How much is a new car battery?
The cost of a new battery car depends solely on the type and model you opt for.
A traditional car battery can cost you around $60 to $120.
On the other hand, premium batteries lie between $90 to $200, and sometimes even more. However, batteries for hybrid cars are costly (costing more than $1000).
In the long run, a car battery lasts 2 to 4 weeks without driving. A new, completely charged battery takes 2 to 3 months to become fully flat.
But ultimately, the battery type, model, health, and external weather conditions decide how long it lasts without driving.
However, if you have any newer experiences to share over the point of discussion, feel free to share us—happy driving with a sound car battery condition.