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Charging a lithium battery to 80% only?

electronics.stackexchange.com

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Re: Charging a lithium battery to 80% only?

#141

Post by watwut »

belltaco wrote: post #14

I wish they would label it so that it shows 100% charge when it's actually charged 80%, and then give an option to 'overcharge' a configurable amount till 125% (the current 100%). That way it will make people aware that they are reducing the battery life by overcharging, and be picky when they overcharge. But this won't happen because reduced battery life is a big direct and indirect(by reducing performance like Appl…

Another reason is that batteries are ... small. Too small. If it charged to 80% from the get go, then your phone is already effectively living on reduced battery, it is already kinda broken because battery runs out too quickly.

Re: Charging a lithium battery to 80% only?

#142

Post by matsemann »

bayindirh wrote: post #124
rekoil wrote: post #116

Earlier quoted context omitted.

> by reducing performance like Apple does with old iPhones What Apple did was clock down the CPU of iPhones with degraded batteries in order to reduce peak load which would otherwise result in crashes that would have made the device borderline unusable below some charge percentage. Yes, they should have shipped the feature off by default and with a toggle, but the feature itself was amazing as it let already old phon…

Apple's know-how in battery management is always a couple of generations ahead of its closest competitor. My 2008 MacBook Pro was able to detect battery problems one year before they started to manifest physically. They did it by adding another controller and an independent firmware to the battery itself, but there was no better tech at that time. M powered MacBooks added auto hold-off (discharge to 80%, keep it ther…

> Apple's know-how in battery management is always a couple of generations ahead of its closest competitor.

> M powered MacBooks added (...)

Things that Lenovo laptops have had for a generation?

Re: Charging a lithium battery to 80% only?

#143

Post by lopis »

artimaeis wrote: post #16
Arainach wrote: post #3

I've given up trying. If a device is willing to lie to me and only charge to 80% while saying it's charged, great, but all of this "try to stay in a range" logic flies in the face of reality. Every device I use besides my cell phone, Nintendo Switch, and Nintendo 3DS has atrocious power drain when not in use. OS does not matter. Windows laptop, Linux laptop, ChromeOS laptop, Android Tablet, Amazon Tablet, you name it…

I just picked up my 2017 iPad Pro. It was last charged Nov 15. Been sitting by the bed mostly unused since. Currently at 80% charge. I haven’t experienced what you’re describing on an Apple device since they switched the laptops away from Intel chips. In my experience, the OS does matter. I can’t believe how bad the rest of the industry is at this. Amazon’s Kindle line is incredible at this IME, but those are pretty…

An android device in standby in airplane mode will last a week in a single charge easily, in my experience. But if you have radio on, yeah, 2 days tops.

Re: Charging a lithium battery to 80% only?

#144

Post by hyperific »

hyperific wrote: post #66
incongruity wrote: post #44

Earlier quoted context omitted.

How is that all that damaging? I’m sure those batteries are recycled in basically all cases and yes, I’d expect battery replacement does indeed forestall replacement for many phones.

The most common processes for recycling lithium ion and lithium polymer batteries are not environmentally friendly. They consume a lot of water and energy and produce toxic byproducts the require further processing and energy to be rendered safe. https://pubs.acs.org/doi/10.1021/acsenergylett.1c02602

byproducts that require

Re: Charging a lithium battery to 80% only?

#145

Post by Reason077 »

vladvasiliu wrote: post #131
tjoff wrote: post #74

Earlier quoted context omitted.

You are right but I disagree. Yes, devices do not charge batteries to 100% as that is directly damaging. And they don't discharge to 0% for the same reason. So they charge to something slightly less. But that slightly less is for all intents and purposes the only definition of 100% we, as end users, have. It's like saying that your CPU is actually only running at 70% clock frequency but overclocking it to 100% would…

While I agree with your general take and hate that my iphone can't be capped to 80% [0], and love that my otherwise crappy hp laptop can be capped to something like 85% (and reports both cap and max capacity), I don't agree with your final take. To take the phone example, mine usually ends the day around 85%. I just don't use it too often. But I sometimes absolutely do and would trade months of battery life for not b…

Of course. All we're asking for is an optional "limit charge to 80%" feature. And, just like macOS has, you can have a very easily accessible "charge to full now" option for those times when you know you're going to need a full charge.

Don't forget, "100%" isn't really 100% any more after a year or two of charging to 100% all the time. You've probably lost 20% or so of your battery's capacity and it will be charging slower due to increased internal resistance.

> "Where does this 80% come from? Would it be even better if I stopped charging at 60%?"

Yes, but only marginally better since there's diminishing returns. 80% is generally considered to be the sweet spot that best balances practicality with battery health.

Re: Charging a lithium battery to 80% only?

#146

Post by KleerKut »

dheera wrote: post #46
p1necone wrote: post #21

Earlier quoted context omitted.

I'm pretty sure most (all?) manufacturers already do (the first part of) this. 100% can't be the point at which the battery literally stops taking new charge - if you did that they'd catch fire all the time. It's just that the manufacturers idea of what "100%" should be generally skews more towards the immediate battery life end of the tradeoff, whereas some users prefer to have "100%" closer to the maximizing long t…

> I know my android phone will let you cap max charge at an arbitrary level Yeah I used to have old Pixel phones as Home Assistant clients on my walls until they all started bulging one by one and I had to treat them as a fire hazard. I now use Samsung tablets, ironically, that have a cap at 80% feature and they seem to be doing fine.

Are those cells 4.4v? Samsung makes great cells, and if you only charge them to 4.2V or less they should last quite a while. When charging to 100% means different things in different cases for the same battery technology then things get murky.

Re: Charging a lithium battery to 80% only?

#147

Post by bayindirh »

pkolaczk wrote: post #136
bayindirh wrote: post #124

Earlier quoted context omitted.

Apple's know-how in battery management is always a couple of generations ahead of its closest competitor. My 2008 MacBook Pro was able to detect battery problems one year before they started to manifest physically. They did it by adding another controller and an independent firmware to the battery itself, but there was no better tech at that time. M powered MacBooks added auto hold-off (discharge to 80%, keep it ther…

> discharge to 80%, keep it there Where? AFAIK this is a feature you need a third party app like Aldente for. The OS does not offer any way to control battery charging level. Yes, it tries to be smart and guess when you need full charge and sometimes decides to charge to only 80% but that doesnt work for all users except the ones with very regular routines and there is no manual control.

I meant the automatic one. My charge cycles are not very predictable, but periodically my Mac says that It'll hold-off charge, and uses battery until 80%, then uses power adapter. Then charges the battery fully later in the day if I'm connected.

Sometimes it flat out refuses the charge. Then I disconnect and use the battery until 30% or so. Then charge when convenient (clarification: It'd possibly charge if I hit a certain percentage, but I always disconnected voluntarily, to give a good use to battery. I lasts a day. Why not?).

My MacBook Air M1 has 165 cycles in 3 years, at 90% of design capacity. I think this is a very solid management of the battery for a computer used every day literally.

My MacBook Pro is at ~85% after 8 years. I don't remember total cycles now.

Re: Charging a lithium battery to 80% only?

#148

Post by bayindirh »

matsemann wrote: post #142
bayindirh wrote: post #124

Earlier quoted context omitted.

Apple's know-how in battery management is always a couple of generations ahead of its closest competitor. My 2008 MacBook Pro was able to detect battery problems one year before they started to manifest physically. They did it by adding another controller and an independent firmware to the battery itself, but there was no better tech at that time. M powered MacBooks added auto hold-off (discharge to 80%, keep it ther…

> Apple's know-how in battery management is always a couple of generations ahead of its closest competitor. > M powered MacBooks added (...) Things that Lenovo laptops have had for a generation?

IBM Thinkpads have "cap charge at n%" setting since 1999 or something, but it's not smart. You set it.

It was also present in HP and Dell's business notebooks for quite some time, but again, it's not smart. Just a pre-defined percentage.

Apple manages maximum charge capacity automatically depending on the way you use your computer.

Re: Charging a lithium battery to 80% only?

#149

Post by ra »

nortlov wrote: post #77
ra wrote: post #69

We just got a Tesla model Y. When we picked it up, they told us to charge it up to 100% at least once per week. Is there something different about these batteries?

Some models (RWD?) are equipped with LFP (lithium iron phosphate) batteries. Tesla recommends setting a charge limit of 100% and, as you mentioned, charging up to 100% at least once per week. https://www.reddit.com/r/electricvehicles/comments/10ji8yk/l...

Yes - ours is RWD.

Re: Charging a lithium battery to 80% only?

#150

Post by TerrifiedMouse »

Reason077 wrote: post #135
rekoil wrote: post #116

Earlier quoted context omitted.

> by reducing performance like Apple does with old iPhones What Apple did was clock down the CPU of iPhones with degraded batteries in order to reduce peak load which would otherwise result in crashes that would have made the device borderline unusable below some charge percentage. Yes, they should have shipped the feature off by default and with a toggle, but the feature itself was amazing as it let already old phon…

> "What Apple did was clock down the CPU of iPhones with degraded batteries in order to reduce peak load" It wasn't what Apple was doing that was the problem, it was the fact that they were initially quite secretive about it! People just started noticing their phones slowing down without explanation. Now days iOS tells if your battery no longer supports peak performance, which is the right thing to do. > "Yes, they s…

I wonder how many products have components that downgrade under specific situations and they never explicitly tell the customer - and most customers don’t ask because it’s “complicated tech” they don’t want to know about it.
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