One of my friend’s laptop battery becomes dead, and after that, he often asks me whether using this dead battery do any harm to his laptop or not?
I researched bad laptop batteries and their effect on the laptop, and after doing a complete analysis, I am writing this article to inform you of everything regarding this.
So, Can a Bad Battery Damage Laptop?
No! a bad laptop battery doesn’t damage your laptop immediately & initially, it does not affect the laptop’s performance. But over time, this battery can shorten your computer’s and other hardware’s lifespan.
Many experts advise that if your laptop’s battery becomes dead, you must replace that battery.
After getting the short answer, I know that you still have many queries in your mind; to clarify your queries, I have discussed 11 major questions regarding bad laptop batteries and their effects on laptop performance. So, keep reading this article till the end.
Table of Contents
What are the Signs of a Bad Laptop Battery?
Many peoples are confused about whether their laptop’s battery is in good condition or if it has become bad. Here I have explained a few signs in which you can understand whether your laptop battery is in good condition or not-

- AGE: Generally, laptop batteries become problematic after 1 to 2 years. If your laptop is 1- 2 years old and facing battery issues, then it is the perfect time to replace the laptop battery.
- Using Time: On average, a laptop battery last between 4 to 6 hours, and if you notice that your battery is dying sooner than it is used to, then it is a sign that your laptop battery is dying slowly.
- Power Issues: If you face unexpected power issues, it is a sign that your laptop’s battery has become faulty.
- Slow Charging: If your laptop is charging very slowly compared to its last time, it is a warning sign for your battery.
- Overheating: All laptops are designed to cool themselves during use and dispel excess heat. If you notice that your computer is hot, then your battery is likely working too hard and unable to cool itself.
These are some of the signs which could silently tell you that your laptop battery is dying day by day.
Does A Bad Laptop Battery Affect the Performance?
Usually, a Bad laptop battery doesn’t affect the laptop’s overall performance; instead, it can shorten the lifespan of your laptop’s hardware.
One of my friends has been using a laptop whose battery has died for the last ten months, and he is constantly running his computer by plugging the laptop charger. Still, he doesn’t face any issues regarding the laptop’s performance.
But, I suggest to him that if he doesn’t replace his battery, it can shorten the lifespan of his laptop’s hardware.
Another disadvantage is that you can only use the laptop as long as it is plugged in. Your laptop will shut down when you travel from room to room or building to building. In simple terms, you have to use your laptop as a desktop.
What Happens If You Don’t Replace your Bad Laptop Battery?
There are many disadvantages of using a bad laptop battery, and I have explained all the problems below that you can face by using a bad laptop battery-

If you are using a battery that is very low at a critical level, doesn’t charge well, discharges so quickly, or damages, then it can potentially ruin the hardware in your device.
The hardware has to draw a specific amount of current (amps) from the battery. The hardware will overheat because the fans do not have enough power to cool the hardware. The heat will cause massive damage to the hardware over time.
Another major issue that could happen is a hardware power surge. When the battery is critical (or faulty), a power surge could occur due to the hardware attempting to draw more current than the battery can supply. This can sometimes cause irreparable damage to the hardware.
Due to this, I have seen several hard- disk and CPU failures. The hard disk was partially corrupted, as the lack of current caused a power surge, which caused the disk heads to jump and scratch the disks.
Therefore, many experts recommend that if your laptop’s battery becomes faulty or damaged and the dust cover is built into the battery, you should stop using the computer and replace the battery ASAP because you are only asking for a massive hardware failure by using it.
Also Read: Windows 11 & Battery Issues (11 Things You Need to Know)
If a Laptop Battery is Dead, how long can You use the laptop Plugged into AC?
If the laptop battery is dead, you can run them forever on the charger with a not functioning battery; it will not harm your laptop. It would be like a desktop where you can run it as long as it is plugged into an outlet.
But, don’t remove the battery because you have no place to store energy without a battery, so your power supply will need to keep up with any instantaneous load.
However, you should not plug your laptop into AC; if your laptop’s battery becomes dead and it is giving you the problems like-
- Battery Swells: This will eventually require the physical removal of the swollen battery.
- Battery Shorts: The battery system overtaxes the AC power brick- resulting in the laptop failing to run correctly. Your computer appears to be dead. Physical disconnection of the battery & removal may fix this issue.
- An Increasingly more Common Problem: Some laptops need some battery power to be present as the included power brick is insufficient to cold start the laptop. Usually, the computer will power on and show the power on a logo but will fail to complete the start-up sequence & instead power off. It may happen intermittently at first. In this case, either replace the power brick with a beefier one or replace the battery.
Can a Bad Laptop Battery Damage the Charger?
Yes! A bad laptop battery may damage the charger because the chargers are usually switch-mode power supplies that regulate voltage and current going into the battery.
You can think of it like this: if a water bottle has a hole in it and the faucet can turn itself off when the bottle is full, could that damage the faucet? It can occur under certain circumstances, but those aren’t super common.
Usually, switch-mode power supplies are generally very intelligently controlled, whereas current mode controllers are within the circuit to regulate how much current passes. In other words, if your charger is continuously pumping energy into a bad battery, it should be able to tell itself to either cut power or limit current draw.
So, in simple words, the short answer is yes, it can damage the charger if the safety features (feedback loops, current-mode control) arent included in the charger.
In that case, you probably won’t want to use that charger in the first place. Keep an eye on your batteries either way; those things can be dangerous in extreme cases.
Will having a Bad Battery in Your Laptop Damage the Power Supply?
No! a dead or bad laptop battery never damages the power supply; it is very unlikely that the dead battery will affect the power supply as when they die, they tend to go open circuit, not short circuit.
So, if your laptop’s battery goes wrong and you are not facing any power supply issues, you can continue with what you are doing.
Can a Bad Laptop Battery Cause (Blue & Black) Screen Problems?
If you are facing screen problems, it is not due to your bad laptop battery because the screen takes less energy than the CPU, and if your laptop’s battery dies, then your laptop screen would turn off entirely instead of causing problems.
But, if your laptop’s screen appears blue, you might have the BSOD (Blue Screen of Death) issue; this issue sometimes arises due to a bad laptop battery or other faulty hardware (RAM, Harddisk).
However, if you are facing the black screen issue, it is not because of your regular battery but your laptop’s CMOS battery. A dead CMOS battery can cause the BIOS to lose its settings, so a black screen is likely.
Will a Bad Battery Keep a Laptop from Turning On?
Yes! a damaged laptop battery can sometimes interfere with the laptop’s starting process, which can cause the laptop’s turning-on issue.
However, a dead battery can often cause power issues even if using a charger as power. In this case, you should open the unit and you need to unplug the affected battery.
Does Bad Battery Make Laptop Slow?
The majority of the time, a bad laptop battery doesn’t slow down your computer, but it can shorten the lifespan of your hardware. But fewer times, it might get slower if you are using your laptop at a critical level or running out of battery.
Another thing you need to know is that some computers intentionally slow down when running on battery power to conserve that power itself. The laptop’s processor or CPU shifts to a slower speed, and processors use less power when they run slower.
Can a Bad Laptop Battery Cause Overheating?
Yes! Sometimes a bad laptop battery can cause overheating issues, but it can also appear because of your CPU.
Sometimes your laptop typically gets hot because the processor produces more heat than the cooling system can dissipate.
So, before deciding about your heating issues, you should check your laptop’s processor & its cooling.
Final Thoughts
So, based on all these things, it has to be said that a bad laptop battery never damages your laptop; instead, it can damage the charger, cause BSOD issues, and bring heating issues. So, it is better to replace the damaged laptop battery.
I hope this article is helpful for you and if you want to know more about laptop batteries, PC components, and other technology-related things, then keep following this blog.
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