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Charging a lithium battery to 80% only?

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Re: Charging a lithium battery to 80% only?

#181

Post by prima-facie »

JohnKemeny wrote: post #153
The_Colonel wrote: post #137

Samsung phones have a good feature which limit charging to 85%. The only thing it's missing is the easy "I want full charge today" button, you need to go deep into settings to toggle this. The other minor annoyance is that subjectively the battery charged to 100% seems to make a bigger difference than the reported 15% indicates - it seems like 30% or even more. Maybe some battery recalibration issue. But it doesn't b…

You (or at least I) can add a quick toggle button called Protect Battery. This makes it as easy to toggle as all the other options like wifi, bluetooth, etc.

This is brilliant, thank you!

Re: Charging a lithium battery to 80% only?

#182

Post by eqvinox »

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?

The percentage is irrelevant, what matters is the charge termination voltage, which AFAIK is lower on all electric cars because you care about battery longevity. I.e. if the same cells were in a laptop, your car showing 100% might only be 80% in the laptop, and it's all good.

(What the actual charge termination voltage [and cell type] is, I sadly don't know and don't know where to find…)

Re: Charging a lithium battery to 80% only?

#183

Post by Libcat99 »

tjoff wrote: post #178
vladvasiliu wrote: post #131

Earlier quoted context omitted.

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…

But that 20% that makes all the difference will only make a difference when the phone is new. Otherwise the opposite is true. Refraining to charge fully makes all the difference and saves you from a tough spot. Which in turn is why (was a bigger problem before) the sentiment that it doesn't matter how good/bad battery life I have as long as it lasts me a day. Well, if you do a complete cycle every day a year old phon…

This used to be an easy problem to fix, by replacing the battery.

Shame that seems to be harder and harder to find on new phones.

Re: Charging a lithium battery to 80% only?

#184

Post by matsemann »

bayindirh wrote: post #148
matsemann wrote: post #142

Earlier quoted context omitted.

> 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.

I've had smart charging in other laptops for ages as well. I'm not saying Apple isn't doing good, I'm just disputing the "Apple is on another league" sentiment, when it's mostly based on a lack of knowledge of what's happening outside the Apple ecosystem.

Re: Charging a lithium battery to 80% only?

#185

Post by MilaM »

This seems to be good advice for single cells. But what about packs with cells wired in series and parallel? My understanding is, that packs always come with a battery management system (BMS) that will balance the cell voltages and therefore compensate for slight variations between cells that can manifest during use and charging. This seems to be necessary for both performance and longevity of the pack. Now the question is, do these BMSs work properly if you never or rarely charge your pack to 100%? I tend to charge packs to 100% to give the BMS a chance to do the balancing and then keep it off a charger for as long as possible. Not sure if my thinking is correct though. Maybe someone with more knowledge could chime in.

Re: Charging a lithium battery to 80% only?

#186

Post by deely3 »

sherry-sherry wrote: post #95
JBiserkov wrote: post #90

Earlier quoted context omitted.

And that's without power saving mode? Impressive! Have you configured anything like "disable background network activity"? Do you force close the apps?

>Do you force close the apps? Don't do this unless an app is unresponsive/not working correctly. It will just make apps slower to restart, using more power than it would if left to suspend/un-suspend as it's meant to.

Issues is: how can I know is app working correctly? I have 15 apps "in memory", my phone started lagging, what should I do?

Re: Charging a lithium battery to 80% only?

#187

Post by bayindirh »

matsemann wrote: post #184
bayindirh wrote: post #148

Earlier quoted context omitted.

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.

I've had smart charging in other laptops for ages as well. I'm not saying Apple isn't doing good, I'm just disputing the "Apple is on another league" sentiment, when it's mostly based on a lack of knowledge of what's happening outside the Apple ecosystem.

Well, I didn't witness on any other current generation device, at least yet. I'm not a fanboy. I'll be happy if others are doing this in some form, esp. if it's independent of the OS itself.

Re: Charging a lithium battery to 80% only?

#188

Post by vultour »

onetimeuse92304 wrote: post #112
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…

Some more responsible device manufacturers are doing this. For example, the industrial equipment I worked with charges batteries much more sustainably, also by charging it with less current. Remember, there are multiple factors when it comes to batteries degrading. Voltage (how far the battery is charged) is one of them, but so is the charging current (how fast ) and also the temperature during and outside of chargin…

I don't understand the obsession with fast charging. I can probably count the number of times I needed to charge my phone instantly on one hand. The other day I bought a MagSafe charger because my new phone doesn't fit properly on my old wireless charger, turns out it doesn't support the "legacy" 5W power bricks. Now it's sitting unused in the drawer because I don't want to charge with more than 5 watts.

Re: Charging a lithium battery to 80% only?

#189

Post by usrusr »

onetimeuse92304 wrote: post #112
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…

Some more responsible device manufacturers are doing this. For example, the industrial equipment I worked with charges batteries much more sustainably, also by charging it with less current. Remember, there are multiple factors when it comes to batteries degrading. Voltage (how far the battery is charged) is one of them, but so is the charging current (how fast ) and also the temperature during and outside of chargin…

And even voltage is just a rough proxy for the actual state of ions in the anode-cathode dance.

When voltage goes down with temperature, the charge state does not change. But drawing a certain amount of joules will be very different because at lower temperature you'll need more coulombs for the same amount of joules, aka VAh.

And at nontrivial discharge throughput, observed voltage will drop to much lower values than what a snapshot of the current ion-dance state would look like at steady state. This is the "smartphone SoC must not try performance bursts as it used to" scenario.

Re: Charging a lithium battery to 80% only?

#190

Post by dalore »

bayindirh wrote: post #147
pkolaczk wrote: post #136

Earlier quoted context omitted.

> 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 c…

> Why not?

I find running on battery, lots of things are throttled or disabled. CPU is slower for example. That's probably a good reason for why not.

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