Windows 10 Stop Charging When Power >80%, Start When <=40

[Lakis01]

Hey everyone,

to prolong battery life I would like a tool, program, way to have my laptop stop charging, when the battery is at 80% (or more?!) of its capacity. To then wait for it to drop to 40% and only then start charging again. This obviously can only be a temporary tweak (e.g. when the laptop is plugged in overnight) as I would need the notebook to be (almost) fully charged at times.

Any ideas?

Thanks!

Markus

 

[Neemobeer]

Newer laptops should actually stop charging when they are full so this would be moot.

 

[Lakis01]

OK, so how do I do that? To have it only start charging at 40% again and not 98%.

 

[Neemobeer]

There is no way to do that I know of. Unplugging the charger is about the only way.

 

[nmsuk]

Newer batteries don't need saving as the old ones did. I'd just let the laptop decide when it wants to charge

 

[Lakis01]

But the laptop always decides to charge, if the battery isn't full, am I wrong?
For one there is Lenovo Power Management, which is good for me as I have a Lenovo LapTop. This takes care of the dont-charge-above-80% thing.
Here someone wrote a script on Ubuntu, shouldn't that be possible on Windows as well? How can I limit battery charging to 80% capacity?

 

[BIGBEARJEDI]

I believe you're operating under old information. How old is that Lenovo laptop you have? Modern laptops, as mentioned above have newer technology lithium-ion battery technology. Older laptops, prior to 2009, often have 1st or 2nd gen lithium batteries which had the top-off problem you are referring to. Many of those batteries were not lithion-ion, they were lithium-MOS or selenium-lithium hybrids. In any case, they were more susceptible to the 40%-80% recharge window you refer to. Most were actually 20%-80% or 15%-85% in fact. Not many battery technologies used the 40%-80% window you mentioned. Newer 3rd gen lithium or lithium-ion-OH batteries don't suffer from this problem or from memory effect issues nearly as much as they did say 10 years ago. That's the reason that no one has written a script in windows to limit an 80% max charging limit. If you're laptop was built prior to 2009 and is 6 years old or older, that battery in their if it's the same one the laptop came with from the factory, is long gone charge-wise anyway and should have been replaced in the first 2 years.

<<<BIGBEARJEDI>>>

 

[Lakis01]

First of all thank you for that extensive information BIGBEARJEDI!
No it is a rather new LapTop; I think it was introduced two years ago. So from the information you and Neemobeer provided I conclude, there is no significantly healthier power interval anymore.
But limiting recharge cycles should still matter, right?
I am not very skilled on the computer, but what I have in mind would be a script (a GUI even better) to let the battery percentage drop all the way to 20, 15% whatever is best (however small the difference for overall battery life may be) and only then start charging all the way to 100% (and not stop at 21, 16%) or whatever threshold is best. Again I have zero knowledge on this, so I believe you guys that it doesn't make a lot of a difference anymore, but since that would be for cases where it is plugged in overnight and I am not using it during that time anyway, why not go for the optimum.

 

[BIGBEARJEDI]

You're welcome. And thanks for your responses back. I believe what we're telling you is that with the newer battery and charging circuit technology in modern laptops such as the one you have no longer require this. You can request people to write a script file for you, or pay someone to write it; but it's not going to help significantly. A question I have for you is that if you google this problem, and it sounds like you have, why is there no software company selling a script or app to do this for windows computers?? Not including the one you found for Linux OS-based computers. Again, my answer is that since it's not necessary no programmers or programming companies are going to spend time writing and testing a commercial solution for this if no one is going to buy it once they find out it's not needed.

There are some of us older guys here who might want to write you a windows script for a laptop built prior to 2009 that uses the older battery technologies and maybe some one of us will respond to your request that has the programming knowledge to write such a script, possibly in php or perl or C++. If they do, you can volunteer to test it out and see if it works on a newer laptop for them and see if it provides any kind of benefit for you.

BBJ

 

[Neemobeer]

There is no way to control this purely with software, on laptops that can do this, they have proprietary hardware and drivers that control this.

 

[Lakis01]

@BBJ: Let's suppose one 20-100% Recharge Cycle is still way healthier than 40 98%-100% cycles even for today's LapTops. There would be several reasons for still no software (paid or free) being available.
A) "Proprietary hardware and drivers" as Neemobeer mentioned is something I didn't even consider, since I thought the resulting script would be quite simple.
B) Even an admin user on windows doesn't have the system permissions are physical ability necessary to "cut power" with the LapTop plugged in.
C) It may be a possible leak for viruses.
D) I guess it is safe to say, that windows is rather targeted at the non-geek consumer market and those products often put simplicity over functionality in order for users to not inadvertently cripple their PC. That would be consistent with the fact, that Linux scripts are available.

The truth obviously is, that I don't know, but leaving the LapTop plugged in all night with it charging 98-100% over and over again just "feels" way unhealthier to me than one 20%-100% (or 80%) charge as mentioned above.

 

[Neemobeer]

I did look at the post for Linux, and that actually required a driver installed.

 

[Lakis01]

+e) We all agree that this would have been useful five years ago or so. So one should be able to find such software in the depth of the internet, but I can't. So I guess A-D were culpable then.

I don't want to be annoying, I just don't like the thought of wasting my battery while the LapTop is working night shifts. Especially when there should be an elegant solution available i.m.o.

 

[BIGBEARJEDI]

I might suggest that instead of subjecting your battery to 365 charge cycles per year, that you REMOVE the battery from the laptop completely, and recharge it only once a month which is only 12 recharge cycles a year vs 365 cycles. I'm sure you'll agree that this will extend the life of your battery significantly more than the software recharge cycle you are hoping to find.

The only time you might deviate from this 12 cycle per year procedure would be if you knew you were going to take the laptop with you for 1 day or more, and so reinsert the battery the night before your trip and run and overnight charge cycle. You could repeat the overnight charging cycle for however many nights you are gone from your home. Such as 7 days of Vacation. If you'll did this once a year, as most people don't travel with their laptops more than that such as daily business use it if you are a University student using in classes. Library, etc.

This puts you at 19 uses of your battery per year vs. The 365 uses you now use. Still way better IMO.

lastly, and hopefully you know this, you should be replacing your Laptop battery at least once every 2 years; no longer! No batteries on the market last longer than this even the $250 factory replacement batteries you buy directly from the OEM laptop manufacturer's websites.
If your Current battery in your laptop is older than 2 yrs., your much sought after scheduled power saver program will not extend your battery life on a battery that's already being used beyond it's end-of-life design period anyway. You might get an extra few months of service, but that's not much, so you'll be replacing your batteries every 2-3 Yrs. for the remaining life of that laptop no matter what you do.

Best,
BBJ

Sent from my VS986 using Windows Forums mobile app

 

[Lakis01]

Hey thanks for the tip! I think I'll actually do that, the only inconvenience would be that I'm not mobile within my house anymore while the battery is removed.

Would there be any software with permissions to bypass the battery, while it's in the notebook? That would be cool, so I could have it run on battery for the few minutes I'm going downstairs.

 

[Neemobeer]

There is no generic software to bypass a battery, the answer would be the same as the charging, proprietary hardware plus a driver to control it.

 

[Lakis01]

Hey I think I've found a workaround. How about a usb controlled power switch? It should be possible to translate 90% battery to switching it off and 30% to turning it on, right?
After thinking about I've decided not to remove the battery whenever I don't need it, putting in additional RAM was an ordeal in itself and I'd have to reset the time & date each time. The letter point can largely be ignored, but I just don't want to put in and out countless screws each time, thanks anyway.

 

[Advo]

The problem with having the battery at 100% is that it ages WAY faster than if it is kept at 80% or (ideally) 40%.
The battery of my Alienware notebook was almost useless after 2 years and completely dead a few months after.
If it had been possible to keep it at 80% or below, it would have lasted years longer.

 

[Josephur]

You should leave it be, the charging circuitry in your laptop is smart enough to charge a battery efficiently and safely. Also batteries are cheap so really it's not worth trying to muck with. Because batteries actually charge on an angled curve and your charging circuit knows how to deal with this properly it's most likely 90%+ efficient at doing so in an optimal manner to charge quickly and preserve battery life. Good battery charging requires understanding of the charge/discharge curve as well as temperatures. (chart not 100% relevant but hopefully lets you know what maths your charging circuit calculates)

 

[Advo]

You should leave it be, the charging circuitry in your laptop is smart enough to charge a battery efficiently and safely. Also batteries are cheap so really it's not worth trying to muck with. Because batteries actually charge on an angled curve and your charging circuit knows how to deal with this properly it's most likely 90%+ efficient at doing so in an optimal manner to charge quickly and preserve battery life. Good battery charging requires understanding of the charge/discharge curve as well as temperatures. (chart not 100% relevant but hopefully lets you know what maths your charging circuit calculates)

I don't care about how the laptop charges the battery. I hardly cycle the battery at all, I use it mostly as a desktop replacement.
The problem is that if the battery is maintained at a high rate of charge, it ages very fast and at the 35 degrees Celsius or so it is exposed to in the laptop will lose in excess of 25% capacity per year, just from sitting there, even if it is not cycled at all. This is called "calendar aging".

If I could keep it at 50%, it would lose much less capacity due to calendar aging.
Samsung used to offer the functionality of charging only to 80%. It was called "desktop mode". Dell apparently has something similar. This would roughly halve the speed of calendar aging, extending the useful life of a laptop battery from 2 years to 4 years.

Unfortunately, my HP notebook doesn't offer this function. I've been considering trying out a low-powered power supply (e.g. 30 Watts) in the hope that the notebook will react to the voltage drop by disabling the charging function (Alienware notebooks do that).