Will a laptop battery deteriorate sooner if plugged in most of the time?

Read just a post on the forum about laptop batteries to get destroyed very quickly if plugged in at 100% to AC all the time.

It reminded me about an article I read a while back when I wondered about laptops’ battery life.

Here it is:


There’s no way to “overcharge” these batteries. When you get to 100% charge and leave your laptop plugged in, the charger will stop charging the battery. The laptop will just run directly off the power cable. After the battery discharges a bit, the charger will kick into gear again and top the battery off. There’s no risk of damaging the battery by charging it over its capacity.

Ultimately, it’s not clear which is worse for a battery. Leaving the battery at 100% capacity will decrease its lifespan, but running it through repeated discharge and recharge cycles will also decrease its lifespan. Basically, whatever you do, your battery will wear down and lose capacity. That’s just how batteries work. The real question is what makes it die more slowly.

I have also come across a variety of oftentimes contradictory recommendations on the subject.

Personally I have my laptop plugged in almost all the time when at home but I am willing to learn new ways of taking care of my laptops battery for it to last as long as possible.

What are your thoughts, experiences, practices, etc on this?

If it’s plugged in most of the time you might want to limit it’s charging capacity to 80%. That’s about the only suggesting I have.


I leave them plugged in unless I need to run it on battery. My T480s is three years old with the original battery, and still charges up to 93% of it’s designed maximum charge. I see zero need to leap through hoops to get a few extra months of total lifespan. Complete charge/discharge cycles is all that really matters. Same experience with multiple T430 batteries. Only one took a dive and it was not genuine Lenovo, it was third party. So anecdotally I would say don’t concern yourself with this endless argument and simply use your laptop as intended


I have specifically set my battery charging parameters for 40-90%. So it won’t charge until 39 and then only up to 90. Now I leave it plugged in a lot more since I don’t need to worry as much if I plug it in at 51% an hour later it’s still 51%

A few years ago, I stopped charging my cell phone over night and I noticed a huge improvement in battery life longevity. After reading about it and learning how lithium ion batteries and chargers work, it was very interesting.

Hey! I also have a t480s!! Why don’t you use the battery parameters if you don’t mind me asking. . .

Its simple to answer.

Do, what the Manufacturer says. And i mean exactly the Manufacturer.

If you have a Notebook from Lenovo for example, the Manufacturer of the Battery isnt Lenovo. It would be another Company. Because they didnt produce the Cells by self. On old Thinkpads for example, its 99% Samsung or Panasonic (18650).

And in they Specssheets, its exactly written that for the BEST use/longlife ratio, they recommend not to load over 60-70%. Because Li-on technology degrades quickly if loaded to 100% everytime. And a 18650 Li-on for example, discharge from 4.2V to 3.2-3.7 VERY QUICKLY in usage. And from 3.7-3.2 to 2.7-2.5 the most Cells delivers the longest time power, without to wear out quickly (naturally, there are exceptions, like how many Amps the systems pulls)

Lenovo have for they Thinkpads a software for example, where it is possible to set a Chargelimit. On linux there are open source tools wich can do that.

For my self, i have my batteries everytime charged to 70% only. Yes, you loose runtime, but in exchange, the lifetime is much longer. For this reason, i simply carry a extra battery with me (if i really need more runtimes as 3hours)

I have Batteries for my X250, W540 and t420 Thinkpads, they now over 7 Years old. And they are still like new.


The information I have suggests that you don’t want to go over 80% (70% is also a good number) and not under 20% (30% is also good). This limits the wear and tear noticeably on li-ion style batteries (applies to cars too!) If you have a tool for automatically limiting it to this, or at least notifying you, go for it!

Of course, battery removal, then running off the wall power (and popping the battery in for an occasional charge to 70-80%) works really well too…

1 Like

Yup - exactly. This is where I got it initially for my Thinkpad T480s. Some newer laptops have this feature built into their firmware because so many people would just “leave them plugged in” and it’s really bad for your battery. Most older laptops do not have the setting, so you need to be much more diligent about it, unless there are some tools added which can do the same thing.

There’s no leaping through hoops. In “Advanced Power Settings” in Plasma for instance on my T480s lets me set the parameters. - I choose 40/90 because that was the settings specified when I used the Lenovo App they built for my computer (on Windows).

When it comes to charging and battery life it comes down to what type of battery you have. Not every device has the same kind of battery. And if you want to really learn about batteries this is probably the best site IMO:

1 Like

Simply runtime is more important to me than longevity of the battery. That and there have been, and always will be an argument about whether or not charge limits increase the longevity or if they give the illusion of helping by artificially limiting the total charge cycles. Decrease in capacity is a function of cycle count and age, this is unavoidable whether you use charge limits or not, and the questionable advantages of using charge limits are a direct hindrance for my usage, especially in the age of integral batteries.

1 Like

I think a 10% yearly battery degradation is to be expected no matter how you take care of it.
If this machine is going to stay 99.99% of the time plugged in, I see no downside of letting it charge only up to 60-80%. I have mine set at 50% and I have great results. Letting it fully charge should reduce the life of the battery considerably. However what kills the battery even faster is heat. Make sure to have good airflow, and maybe use undervolting to keep the CPU cool.

1 Like

How did you get the charge limit settings in KDE? Do you have another package installed that gives you this? I don’t have this on my KDE install.

Edit: This is a Lenovo thing built in?

I’m a battery researcher and most of the points on this thread are correct. I just want to get my 2 cents in.
Not all solutions work for all batteries as they use different chemistries even though they are all Lithium-ion.
There are three main ways batteries degrade: 1) Cycling 2) Calendar aging 3) High temperature. And these rates are different for different batteries.

  1. Cycling: Charging your battery and discharging. As mentioned earlier in the thread by @freebird54, you want to keep them between 20-80% for the longest battery life. This is because batteries degrade more at higher and lower SOCs (state of charge). Even better is if you can disable quick charge. Batteries degrade faster when charging at higher currents (which is what quick charge is).
  2. Calendar aging: This happens when you are storing the battery i.e. not using it. Again the same principle. Avoid lower and higher SOCs. For example, if you always keep your laptop plugged in, a SOC of 50% is ideal. You can push it to 80% if you need more capacity when on battery. This is the reason why in many manuals it is recommended that when removing your battery for storage you do so at 50%.
  3. Battery Temperature: As my advisor says, batteries are like humans in the sense that they are comfortable in temperature ranges humans are comfortable in. Avoid low temperatures and high temperatures. As @nate mentioned above, undervolting to keep the CPU cool is a good place to start to keep temperatures low. Also using a cooling pad, cleaning the vents on your laptop, using laptops on flat surfaces which allow decent airflow to keep temperatures low is recommended.

These are just general principles most Lithium-ion batteries will follow. Results might vary based on battery chemistry. Batteries are getting better with regards to life so newer batteries using newer technology might last longer.

Hope this is helpful. Please message me if you have any questions or want clarifications.

edit: As suggested by @mcury it is recommended to do a full charge-discharge, once a month or so (more frequently or less frequently is also fine). What this does is calibrate the battery capacity so the SOC what you see on your screen i.e. the charge % is accurate.


I heard someone saying that it’s good to give a full cycle in the battery with an interval of 15 days…
From 0% to 100%, then keep it from 40% to 80%…
I have doing this with my phone (galaxy s10), and so far my battery seems like new, around 30 hours uptime…
I bought around 2 years ago


I assume it has to do with my firmware? I didn’t install anything specific I’m aware of. . .

1 Like

Yes, not all laptops support this. I know Lenovo does (because I use Lenovo :grin:); I have no idea what (if any) other platforms might support it.

I don’t see any settings on this ideapad 3i which just has Windows on it though. I checked the UEFI Bios and it’s pretty basic.

I have no idea what Windows has for power management settings, sorry.

I had to download the Lenovo advantage software I think? I’ll look when I get home.

I have that on Windows currently on this ideapad 3i so i was just wondering. I’m going to look at it on the Thinkbook that i bought. I bought the ideapad on a whim for one of my kids.