Why is Battery wear level constantly changing?

[Bill_Bright]

When I say "drain to zero", I mean "drain to 3.0V" or "drain to 2.8V" or whatever the heck the manufacturer thought was a safe cutoff voltage. No one actually goes to 0V

Right. At least they don't intentionally. I suspect it was shortly after the very first lithium based batteries were developed that they discovered discharging them to 0V could permanent damage the cell. So they quickly developed the necessary internal device to stop discharge once it reaches a certain level - and I think 2.8V is pretty most common.

However, while output is terminated, the chemical process still continues and, like all batteries, they will continue to discharge, even if sitting on a shelf - though at single-digit µA rates. If left long enough, they will eventually reach 0V. For this reason, it would not be wise to run a battery down, then pull that battery and put it on the shelf. It is best to charge it up a bit (50% seems to be a common consensus), if the device is to be unused for awhile.

The point really is about semantics. 0% charge does not really mean 0V. However, if 0% charge is indicated, a multimeter may very well show 0V, but that is because output has been terminated.

 

[dragontamer5788]

To this moment nobody was able to provide a clear explanation on how calibration actually works and why it’s still necessary, everyone said that “it just is”. I am sorry if that annoys you but that doesn’t count.

Lets assume 2.8V is the cutoff for some hypothetical battery. When you drain to 2.8V, the battery's circuits will shut off for safety reasons. Lets call the 2.8V event a 0% charge.

From there, you plug the battery into the wall. The coulomb counter counts 40 Watt-hrs into the cell. Your coulomb counter now knows that 40W-hrs were put "into" the cell. It then multiplies the 40W-hrs with efficiency (maybe 90%), and thus knows that 36W-hrs are expected to come out. That's calibration, you have an accurate count of what was pumped in, as well as having an accurate expectation of what will happen as you use the battery. Lets call 40W-hrs 100% charge (or 36W-hrs actually in the battery).

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Now lets say the next month happens: you use 10 W-hrs, then charge up 5 W-hrs, then use 8 W-hrs, then charge 10 W-hrs. What's the charge? (Lets say the 90% efficiency thing was already factored in: for simplicity's sake). Well... its more complicated than just counting it up! Not only is the 90% efficiency thing going on, but that efficiency varies with temperature and usage. As such, this coulomb-counting method gets less-and-less accurate the longer you go without a calibration event.

So after +40W-hrs -10W-hrs + 5W-hrs - 8W-hrs + 10W-hrs, you'd expect 37W-hrs remaining. But in fact, maybe your 90% efficiency estimation was off (and the battery was in fact: 92% efficient), so you're "really" at 37.5W-hrs or so. This difference between "reality" and "calculated" continues to diverge until your next calibration event. Or maybe, your battery was in fact 88% efficient, so you have less battery than you expect.

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Could you calibrate off of the top? Sure you can. As a Li-ion battery reaches the full-side of its charge, its voltage goes up to 4.2V or so (a 100% event, so to speak). So how much charge is remaining once you're at 100%? Well... maybe your battery has been worn out in the past month, and can only hold 32W-hrs now. Without actually discharging back down to 2.8V, you'll never know.

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Without a "discharge to 2.8V" event, you don't know how many Watt-hrs are "in the battery". Especially because the charge-level varies upon temperature, time, manufacturing, and usage. (Discharging at 1A changes the characteristics more than discharging at 0.5A).

 

[Vya Domus]

Well... its more complicated than just counting it up! Not only is the 90% efficiency thing going on, but that efficiency varies with temperature and usage. As such, this coulomb-counting method gets less-and-less accurate the longer you go without a calibration event.

So it’s not that useful like I said, I am sure you’ve used your phone for weeks without calibrating it once and it still behaved like you’d expect it to. The charging circuits are accurate enough for that to not be a big problem.

 

[dragontamer5788]

So it’s not that useful like I said, I am sure you’ve used your phone for weeks without calibrating it once and it still behaved like you’d expect it to. The charging circuits are accurate enough for that to not be a big problem.

I actually calibrate my phone's battery on a regular basis to keep the charge count more accurate. And yeah, the phone sometimes drops down to 15% and then stays at 15% for hours when its poorly calibrated. Strange behavior at first sight, but once you understand how these things work, its not so mysterious. Those coulomb chargers really are guessing-and-checking.

Anyway, enough of theory. The proper answer directly from Lenovo themselves: https://support.lenovo.com/us/en/so...y-gauge-reset-using-energy-management-ideapad

Lenovo has a specific page on the Ideapad for how to calibrate your battery monitor / coulomb charger. It depends on the software that was installed on your laptop. But in both cases, all it does is make your Ideapad drain from 100% to 5%, and then recharges your laptop after that. These coulomb counters are in the battery itself, not really part of the "laptop" per se. So you can do a 100% to 5% charge yourself and it'd probably calibrate just fine. (But feel free to use the software to automatically "spend battery" at 2am while you sleep or something).

 

[Bill_Bright]

And I explained why calibration used to be done and how it’s pointless now, quite thoroughly I’d say in my last comment. You just ignored everything and defaulted to telling me to just google it and copy pasted a bunch of stuff you found.

And you just expect everyone to accept what you say because you said it - yet you are the one calling others arrogant.

and copy pasted a bunch of stuff you found.

Oh, you mean all that supporting evidence I provided to support what I said? Do you even know how to use Google to research and verify your "alternative facts"?

You should write to Samsung and tell them they don't know what they are talking about either: How To Calibrate Your Battery? | Samsung Hong Kong
For sure, you need to tell them to remove that feature from their BIOS menu too because obviously, Samsung knows nothing about Li-Ion batteries either, right?

I actually calibrate my phone's battery on a regular basis to keep the charge count more accurate.

Right. A quick Google search shows how. Battery calibration on Android: How to do it? | Technobezz or How to Calibrate the Battery of Android Phones for Accurate Power Readings (online-tech-tips.com)

or How to Calibrate an iPhone Battery in 6 Easy Steps (makeuseof.com) and How To Calibrate iPhone Battery | (appledystopia.com)

 

[Vya Domus]

A quick Google search shows how.

Funny that you also get this in the results if you look up "phone battery calibration" : https://www.makeuseof.com/tag/battery-calibration-for-android/

 

[Bill_Bright]

Okay. You win. One link to rule them all.

I'm outta here.

 

[dragontamer5788]

Funny that you also get this in the results if you look up "phone battery calibration" : https://www.makeuseof.com/tag/battery-calibration-for-android/

Battery calibration is a simple task; we covered how to calibrate an iPhone battery. It's basically a full cycle of recharging.

First, drain your phone's battery completely. Don't charge it at any point while it's draining. Let the phone keep working till it shuts itself off.

Once the phone has shut itself off, restart it so it shuts off again. Even though the battery was at 0 percent, it has a few reserves left. Now, while the phone is off, charge it to 100 percent. It's safe to use quick chargers for this, but make sure you hit 100 percent.

Your link doesn't even contradict anything we've said in this topic.

 

[Vya Domus]

Your link doesn't even contradict anything we've said in this topic.

It wasn't meant to. What all of you said more or less is that battery calibration is 110% without doubt absolutely necessary and you need to do it all the time and that the battery will go bonkers if you don't do it. Which are vague and unverifiable claims to begin with to be honest and that article simply talks about why that's not the case. But you are free to interpret it whichever way you want.

Still no conclusive evidence that calibration is actually necessary though, I am sorry but there just isn't any.

I'm outta here.

Shouldn't have even started this.

 

[dragontamer5788]

What all of you said more or less is that battery calibration is 110% without doubt absolutely necessary and you need to do it all the time and that the battery will go bonkers if you don't do it

Holy strawman batman.

 

[Vya Domus]

Well, my exaggeration is overcompensating for the weakness of those claims.

 

[dragontamer5788]

Well, my exaggeration is overcompensating for the weakness of those claims.

I'm trying to help the original poster of this topic figure out why his Lenovo Battery performs as follows.

Within the first 2 months battery wear reading from Hwinfo was always 0%.
After a bit of time went to like 5% and since then constantly changing between 2% to 5%.

What are you planning to contribute in this topic, exactly? From the description in the very first post of this topic, it sounds like a miscalibrated coulomb counter. Do you think anything else could have happened here? If so, why?

 

[Vya Domus]

I said what I believed was happening in my very first post, then I got dragged in all this. Not much else I can add.

 

[dragontamer5788]

I said what I believed was happening in my very first post, then I got dragged in all this. Not much else I can add.

Battery calibration is not a thing anymore it also has nothing to do with the wear level.

As far as I know "wear level" is simply a measure of how much voltage the battery provides compared to the nominal value. Basically as time passes by that voltage is supposed to drop, however it can still vary based on temperature and such.

As you can see from the typical Li-ion voltage curves, there's no way in hell to tell if you're at 80% charge or 20% charge from the voltage curve. In fact, temperature has a higher-effect on voltage in that zone than state-of-charge. Voltage-curves are damn near useless, except for determining the extremes: 100% or 0%. (That's why all calibration-processes ask you to go to "near 0%" or 5% or whatever, and back up to 100%)

Your assumptions about "reading the voltage provides vs a nominal value" is obsolete, and only applies to Alkaline and Lead-Acid batteries IIRC. Damn near everything is Lithium-ion or Lithium-polymer these days, with a similar "flat curve" for the bulk of the charge zone. That's why we use coulomb counters primarily to measure state-of-charge.

 

[Vya Domus]

As a lithium ion battery loses it's maximum charging capacity the maximum voltage drops as well, hence you can infer the wear level of the battery. That's how most batteries "die", they just don't output enough voltage anymore as they hit 70-80% of their initial capacity.

 

[R-T-B]

It wasn't meant to. What all of you said more or less is that battery calibration is 110% without doubt absolutely necessary and you need to do it all the time and that the battery will go bonkers if you don't do it.

Who the heck said that?

We said it can offer benefits. This is a bit dramatic.

As a lithium ion battery loses it's maximum charging capacity the maximum voltage drops as well, hence you can infer the wear level of the battery.

The chart... it's right above you.

 

[WatEagle]

I'm trying to help the original poster of this topic figure out why his Lenovo Battery performs as follows.



What are you planning to contribute in this topic, exactly? From the description in the very first post of this topic, it sounds like a miscalibrated coulomb counter. Do you think anything else could have happened here? If so, why?

i'll try to see if draining almost to 0 and then going with a full charge will solve this... In the past wear level was about 1.2% and doing this solved the issue

 

[elghinnarisa]

How to calibrate the battery using OneKey Optimizer - Windows - ideapad - Lenovo Support US

support.lenovo.com

Lenovos directions for battery calibration. I recall being through them before because my lenovo laptop (legion y520) had battery issues, which turned out not to be related to anything fixable without warranty/RMA claim but thats another story.

Even then, im not sure I would care with such a small wear level reading. I don't think I ever had a battery that was 100% to the spec of the battery, always a few % off, which (depending on application/device) showed up was wear or capacity reduction.

 

[WatEagle]

How to calibrate the battery using OneKey Optimizer - Windows - ideapad - Lenovo Support US

support.lenovo.com

Lenovos directions for battery calibration. I recall being through them before because my lenovo laptop (legion y520) had battery issues, which turned out not to be related to anything fixable without warranty/RMA claim but thats another story.

Even then, im not sure I would care with such a small wear level reading. I don't think I ever had a battery that was 100% to the spec of the battery, always a few % off, which (depending on application/device) showed up was wear or capacity reduction.

sadly I can only use Lenovo Vantage software. One Key optimizer isn't available for my specific laptop and Lenovo Energy Managment is installed but not usable like they show on the site

Just for your info...there is a software utility called BatteryCare which takes care of cycling of your battery automatically..

I've just installed it and it shows the same wear level as HwInfo, but says 0/30 discharge cycles and no calibrations done so far

 

[Bill_Bright]

I said what I believed was happening in my very first post, then I got dragged in all this. Not much else I can add.

Oh bullfeathers! This is just more of your twisted nonsense and yet another one of your misrepresentations (to put it nicely) of what others have been explaining to and showing you.

You were not dragged into anything. You jumped in with your first post when you declared calibration is "not a thing". You attacked with puerile personal insults when you didn't agree. You have ignored the fact that no one else in this thread supports your claim that calibration is "not a thing". And you summarily dismissed all the evidence presented to you, calling it "a bunch of stuff" that was just cut and pasted from Google!

You post one link and pretend it makes all others null and void when it is clear you didn't even read, or didn't understand your own link! Your link clearly explains how to calibrate smartphone batteries and further explains how battery calibration, "lets the chip calibrate its readings with the battery's charge cycle". In other words, it is about ensuring accurate "monitoring" by the device's monitoring and battery status features - exactly what everyone (but you) have been saying all along - including what I said in my first post.

You repeatedly misrepresent (love the "strawman" comment! ) what others have said. Nobody was talking about memory effect. Nobody (but you) said calibration is not useful. And nobody said anything about 110% necessities or batteries going bonkers.

So, once again, according to you, everyone else is wrong, all the supporting and corroborating evidence we presented is wrong. Even your own link must be wrong. But you are right.

 

[Vya Domus]

Dude, stop.

 

[Bill_Bright]

No more BS and I assure you, I will remain gone.

 

[Vya Domus]

BS ? Incredible, still acting like a arrogant 14 year old.

I had enough of your nonsensical rants, off to the ignore list you go.

 

[Bill_Bright]

I had enough of your nonsensical rants, off to the ignore list you go.

Wonderful! Thank you.