Develop Bugs

Battery abruptly drops from 40% to zero

Hello, I'm having issues with what I think is battery readout miscalibration on the HTC One M9.
The battery life is relatively short (several hours) and it consistently exhibits the following behavior. At 60-70% it reboots but then continues to work, and then at 40-50% it dies and displays "0%" battery message when trying to boot.
For charging I am using either a Tronsmart Quick Charge 2.0 wall charger or a 1500mAh power bank that provides 5v 2A.
As soon as I plug the phone in for charging, it tells me the battery level is where it was before shutting down, e.g. 40-50%.
I am attaching a picture where the phone shut down because of dead battery, and continued to go on for a while (before dying again at 40%). You can see it dying its second death in the far right, at 40-50%.
I am running Vodafone UK Marshmallow RUU, but the same issue happens with CM13 and Android Revolution HD.
I believe it to be related to the fact that the pmi8994 battery controller incorrectly reads what actually is close to 0% battery as being 40% or higher, and as such also reading 100% when the actual battery is less than that.
I have tried following these steps in the M8 forum, but I don't see a visible result. But I am open to other suggestions on how to reset this power management controller.
http://forum.xda-developers.com/showthread.php?t=2765663&nocache=1
I also have a last_kmesg file from /data/system/dropbox/ but I do not understand the underlying reasons for reboot, only that it is related to battery. If you could figure it out I have attached the kernel log.
Since the behavior is always consistent, I strongly incline to believe the problem is in software (or firmware, to be more exact) and not that the battery is dying. What is your opinion and what debugging steps should I follow? Maybe the battery reset procedure changed since the M8? How can I check that it actually worked?

What i find wierd is the wifi stays on while the entire system is off..
Have you tried completely resetting back to stock and start over?
I was going to suggest running the battery flat flat and recharging it (if you have a magnet place it on the cable to steady the flow from the charger as you don't know if that could be dropping or spiking) but it might never charge again if the software is the issue.. Don't forget the battery is eeprom controlled and can easily be the cause.
Beamed in by telepathy.

Yes, wifi always on is very strange although I hadn't noticed that detail.
I haven't tried completely reflashing a stock RUU, since I am S-ON and unlocked bootloader. I have only flashed back and forth custom ROMs like CM13 and Android Revolution, and now restored my TWRP backup of the stock Vodafone ROM.
What do you mean the battery is EEPROM controlled? Is there any image in HTC update.zip which rewrites the battery controller (PMI 8994) firmware?
My plan would be to let the battery completely drain today and tomorrow, and then pick it up again on Sunday, relock bootloader and apply a new RUU on the phone. How does that sound?
BTW, my CID is VODAP001, what would be the best RUU to flash?

You would have to go through the reset to stock procedure. You can find it in flippys thread in the general section.
Beamed in by telepathy.

I have went completely through the procedure you described (left the phone discharged for a few days, then reset to stock).
Still no improvement. It also started to reboot while charging, which it didn't do before.

It looks like the battery had simply gone bad.
I had it replaced and now it works fine.

[Q] SM-P600 weird (battery?) issue

This past week, I purchased a 2014 Note 10.1 off Craigslist. I did check it out before buying it, and the device is in pristine condition, including the screen. It booted fine, and I went partway through the setup (the guy had factory reset it) before closing the deal. It is the wifi-only model, 3G RAM, 8-core Exynos version. It's white if that matters.
Anyways, a while later when playing with it some more, completing setup, etc, it just died on me. I wasn't home, and didn't have a place to charge it until I got home, but just figured that despite the device having said the battery was 99% charged, the guy keeping it unused for a long time might have thrown off the battery calibration. My understanding is that a Li-ion battery has one or more cells, plus circuitry that protects against overcharging and undervoltage conditions, as well as tracking the current charge state. With lengthy non-usage, the circuitry's idea of the current charge can get out of sync with reality, so I figured a few charge-discharge cycles would get it back in shape.
However, the situation after I got home turned out to be a little more complex. If I plug in the device to a power source with enough current (like the charger it came with, or my 2.1A USB outlet by my bed), it will run just fine while plugged in. However, upon unplugging, it would die quickly. Naturally, I assumed the battery was probably shot, so resigned myself to spending $50 on one. This is where it started to get a little weird. It seemed that when I booted into either fastboot or Odin mode, it would stay on much longer than normal, while unplugged. I'm talking hours, rather than between several seconds and several minutes while booted into the OS proper.
This lead me to believe that perhaps it wasn't my battery itself, but rather a glitch in the OS that was causing it to shut down. When I say shut down, I mean an immediate full-off state, not a nice shutdown or one preceded by low battery warnings. It just clicks off like a light that's been turned off. However, trying several different firmwares, including a couple custom ones, has not yielded any improvement. The issue remains.
The device was stock 5.1.1 when I bought it. I tried flashing KitKat (various images downloaded from SamMobile), but for some reason, it would still say it was running 5.1.1. I tried xKat, as in this thread. That results in 4.4.2 with the associated customizations, but the shutdown issue remains. I tried CyanogenMod 13, as instructed here. It works fine, notwithstanding the same issue. In between the stock firmwares (pushed to the device with Odin) and the custom ones, I would do a full wipe through TWRP.
I've popped the back off, disconnected the battery, waited a bit, and reconnected it.
Now my question: does anyone have any idea what's going on? If it's a dying battery, then why does the device say it's got a nearly full charge, and why no low battery warnings? Why would Odin mode or recovery (TWRP now) seem to keep the device powered up so much longer? Sure, they draw less power, but hundreds of times less power? I doubt it. If it's some hardware issue with the chipset/motherboard/etc, then why does it only manifest when running on battery, or a low-current USB connection? If it's an issue with Android itself, then why does nobody else seem to have this issue (googling revealed nothing that matched my symptoms), and why did several different versions exhibit the exact same problem?
I really don't want to spend money on a new battery and wait a few weeks for shipping if there's something else I'm missing that could get my device functional for free and a lot faster.

My tablet had a similar issue, in that when you would get to the 15% mark, I had maybe 3-5 minutes before it would get to 0% and abruptly turn off. I used the battery calibrator app for rooted devices, followed the instructions, and now all is good again. For me, I noticed a variance from what the OS was reporting and twrp was showing in between flashing. For what its worth, I'm on the KitKat bootloader, and haven't used an official Samsung firmware since KitKat. Oddly enough, the battery calibration having been off survived through lollipop and into marshmallow. Hopefully you can get your tablet back on track.
Sent from my SM-P600 using XDA Premium HD app

Thanks for your reply.
siralsmooth said:
My tablet had a similar issue, in that when you would get to the 15% mark, I had maybe 3-5 minutes before it would get to 0% and abruptly turn off.
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Click to collapse
That's a bit different from my issue. Even when the device reports full charge, if I unplug it, it usually dies within seconds, and always within 2-3 minutes.
siralsmooth said:
I used the battery calibrator app for rooted devices, followed the instructions, and now all is good again.
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Click to collapse
I don't think that's going to make a difference for me. From what I was reading, all it does is delete the batterystats.bin file (hence the root requirement), which doesn't have anything to do with calibration for most devices. It just contains the stats for how much battery drain various things have caused, during this 'running on battery power' session. It's also reset every time the device is charged. Read here for more info.
Furthermore, even if this were not the case, I'd conclude that wiping the system partition (indeed, all partitions except recovery) would have cleared this data.
Still, that said, it's conceivable (though exceedingly unlikely) that some of these calibration apps might do something else, such as talk to the battery circuitry at a low level. Since I've got nothing to lose, I will probably give a few of them a shot. Do you happen to know which one it was that you tried?
siralsmooth said:
For me, I noticed a variance from what the OS was reporting and twrp was showing in between flashing.
Click to expand...
Click to collapse
In my case, the values seemed to track pretty closely, and with numerous freshly-flashed versions exhibiting the same issue, I'm pretty sure at this point it's not a software glitch. I've resigned myself to ordering a new battery. I just wish I was certain that it would fix the issue.
siralsmooth said:
For what its worth, I'm on the KitKat bootloader, and haven't used an official Samsung firmware since KitKat. Oddly enough, the battery calibration having been off survived through lollipop and into marshmallow. Hopefully you can get your tablet back on track.
Click to expand...
Click to collapse
My understanding is that the bootloader doesn't change with flashing. I might be wrong though; is there a way to check the version?

Just a heads up. I ordered a new battery, which arrived yesterday. It seems to have completely solved the issues I was having.
My guess is that Android itself monitors the battery more diligently, and takes a more conservative approach to preserving battery life by shutting down when the voltage drops too low, while recovery mode would just let it run down completely flat (not good for Li-ion cells).
It's a moot point now, because it all seems good.

Bad Battery?

I know. I've seen the threads for battery drain and such, but I don't think there's a problem with "drain" so much, as perhaps a bad battery altogether.
I'm using my old M8 for my daughter, but after RUU, and setting up latest TWRP and all, then trying to install a custom ROM whether Stock or AOSP, when I boot into recovery, it goes from 100% within the ROM, to show 80% in recovery.
If off the charger, there does appear to have some battery drain, but I chalk that up to normal first usage.
However, it then shuts off @ 30%, but when I put it on the charger, it says @ 60%.
I've done the calibration method (hold all buttons for 2 minutes) trick, but there appears to be no help for the erratic battery readings.
Does anyone know if my suspicion is correct?
I'm on Sprint's last RUU.

mcwups1 said:
Does anyone know if my suspicion is correct?
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Ive seen so many posts now that refer to the exact thing you mention. Phones turning off at 20-30%. Its claimed that this is due to a faulty battery and a replacement has fixed it. I do not have this problem, however, I did get a replacement 12 months ago.

That's what I'm afraid of.
Did you replace it yourself, or have a tech do it?

mcwups1 said:
That's what I'm afraid of.
Did you replace it yourself, or have a tech do it?
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Click to collapse
I replaced mine just Yesterday, with both speakers, chraging portero AND buttons, its not that hard AND not easy, you Will nerd a razor blade, AND see a few videos first, one thing to have in mind Is that i put a m9 battery on my m8, AND the phone works, but the phone doesnt recognize the aditional 240mamps,. AND the battery temp always shows 25C, but besides that everything is ok, waiting for the battery yo settle.

HTC 10 while completely shut down lost 35% battery level in 1 day

While waiting for a replacement SIM card for my HTC 10, I had fully charged it then powered it off. The next day, I wanted to check something on the phone, so I powered it up. The battery level wasn't 100% or in the 90's... it was a shocking 65%.
I've owned 4 different Android cellphones prior to this one. None of them ever exhibited this kind of power drop while shut down. Most lose just a couple of percentage points when in standby. Clearly something is wrong with this phone...
Does anyone know if there's any kind of parasitic drain on the battery of the HTC 10 even while completely off? It's running Oreo. Either this, or the battery is somehow worn out enough that it can't even hold a charge when sitting idle. Any ideas?

Hi, maybe your battery is not so healthy anymore.
Still you can try this:
''Power off phone.
Plug phone into HTC charger and charge for two minutes or more
While charging, hold down volume up+volume down+power button and continue holding
Phone will turn on and off repeatedly every 15 seconds or so while continuing to hold all three buttons
Keep this going for 2 minutes, then release buttons when phone is ON
Now, let phone charge fully normally (with phone either on or off--doesn't matter) and battery level reporting, charging and battery life should be normalized.''
Supposedly it's the recommended procedure by HTC.

^ Yes, I'm very familiar with that procedure and had done it several times. And then was fully charged after that. And by the way, I said 1 day but it was actually 12 hours later, which is even worse!
I conducted another experiment... with the phone battery level at 77%, I first put it in Airplane mode and then shut it down completely. Well, about 18 hours later, guess what? Battery level showed 76% upon boot up! Remarkable. If the phone is SHUT DOWN, I can't understand how there would be any possible parasitic drain difference between normal mode and airplane mode. There should be NOTHING running. Or, instead of parasitic, this may just be happenstance of what cells inside the battery itself were taxed. I'll have to try this again from 100% charge, just to be sure.

battery
cytherian said:
^ Yes, I'm very familiar with that procedure and had done it several times. And then was fully charged after that. And by the way, I said 1 day but it was actually 12 hours later, which is even worse!
I conducted another experiment... with the phone battery level at 77%, I first put it in Airplane mode and then shut it down completely. Well, about 18 hours later, guess what? Battery level showed 76% upon boot up! Remarkable. If the phone is SHUT DOWN, I can't understand how there would be any possible parasitic drain difference between normal mode and airplane mode. There should be NOTHING running. Or, instead of parasitic, this may just be happenstance of what cells inside the battery itself were taxed. I'll have to try this again from 100% charge, just to be sure.
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Click to collapse
I have what may be a similar problem , I charge phone to 100% let it sit , it drops to 43% when I pick it up it reboot and continues to reboot, boot recovery now it shows 1%, plugin phone boot up and it shows 43%.

pbazw said:
I have what may be a similar problem , I charge phone to 100% let it sit , it drops to 43% when I pick it up it reboot and continues to reboot, boot recovery now it shows 1%, plugin phone boot up and it shows 43%.
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Click to collapse
I think that when you charge it to 100%, it's not really 100%. The phone may be displaying that figure, but the battery isn't fully charged. And if your battery has suffered deep discharge a number of times, it could have a very diminished mAh capacity at this point. This is why the phone continues to reboot. The operating system starts and it thinks there's enough power to start up, but the battery is actually down to 1%, so the battery protection circuitry kicks in and forces a shut down. The operating system doesn't register this as a normal shutdown, so it goes into reboot mode. And thus, pattern keeps repeating until you plug in the phone to a power source.

Well, I did another test. I charged the phone up to 100%, put it in airplane mode, and then shut it down. A little over 12 hours later, I turned it on and battery level showed 98%. That was curious. Did airplane mode really make a difference? Didn't make sense... until I decided to reboot the phone, just to be sure. And guess what it showed after that? 61%. So my theory was right -- there is no parasitic drain really. It's the battery having some kind of problem. I rebooted again... 59%. Rebooted again 59%. Then I held down all 3 buttons for 5 cycles and rebooted. 59%. So that is actual.
When I charged up the phone, I had done the 3 button hold-down a couple of times and recharged until rebooting stayed in the upper 90 percent. So, the phone most definitely should have been fully charged. This battery is damaged... and given what I learned from the previous owner, who simply never let it drop down below 50% (always recharged when between 50~60%), and pristine external condition, this is just a prime example of the substandard battery and/or battery management firmware.

cytherian said:
Well, I did another test. I charged the phone up to 100%, put it in airplane mode, and then shut it down. A little over 12 hours later, I turned it on and battery level showed 98%. That was curious. Did airplane mode really make a difference? Didn't make sense... until I decided to reboot the phone, just to be sure. And guess what it showed after that? 61%. So my theory was right -- there is no parasitic drain really. It's the battery having some kind of problem. I rebooted again... 59%. Rebooted again 59%. Then I held down all 3 buttons for 5 cycles and rebooted. 59%. So that is actual.
When I charged up the phone, I had done the 3 button hold-down a couple of times and recharged until rebooting stayed in the upper 90 percent. So, the phone most definitely should have been fully charged. This battery is damaged... and given what I learned from the previous owner, who simply never let it drop down below 50% (always recharged when between 50~60%), and pristine external condition, this is just a prime example of the substandard battery and/or battery management firmware.
Click to expand...
Click to collapse
I experienced something like that last week, where I left it in airplane mode for like 8 hours. I went out did things, came back later and it was litterly being reported at the same thing. Like 68%. It was really weird. Then I had started using the device for like an hour. And it only dropped like 1 or 2%. It was the exact opposite of what we are used to seeing. I was doing youtube, playing a game. Not normal. Then finally the drainage started up again.
Today the device dropped pretty quick to around 35% so I plugged it in to charge. Came back like 15 minutes later and it was reported around 69%. I thought that was way too quick for 15 minutes. Granted it was a quick charge 2 charger, but still, I've never seen that quick of a charge on the 10 or my V20.
I'm really at a loss what to think as far as calibration, what the battery is telling us. I'm thinking of unlocking, throwing on Leedroid and Elemental kernel. I just don't have the time to go through all that yet. Glad I have my backup phones.
My 10 is also like yours in pristine condition. Granted I didn't ask how the seller how tye used the battery before me, but I also never researched problems with the 10 before buying. I was under the assumption since I've been an HTC customer from the M7 and M8, that the 10 would also have a good battery. Same or maybe better than my V20. Especially since they both use the 820 chipset. I guess I'm paying for my ignorance now.

gustav30 said:
My 10 is also like yours in pristine condition. Granted I didn't ask how the seller how tye used the battery before me, but I also never researched problems with the 10 before buying. I was under the assumption since I've been an HTC customer from the M7 and M8, that the 10 would also have a good battery. Same or maybe better than my V20. Especially since they both use the 820 chipset. I guess I'm paying for my ignorance now.
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Click to collapse
Same as you... great value from HTC phones up until the HTC 10 (having skipped the M9).
I'm in a pre-return mode right now with the seller. She has given me the OK to do a return. But I'm going to see if she might welcome the opportunity to do a partial refund. Because if she takes back the phone I don't know if she's going to try reselling it or give it to a family member to deal with. It's a hassle selling a phone that has problems. My thought is, if I can work out a good price (like half the cost of a typical charge--got two quotes for $140 and $150), I'll go ahead and try to do the battery change myself. But then... I'm a little unsure about jumping down that rabbit hole. It may work fine, but I usually keep a new (to me) phone for at least 2 years. If I'm having battery trouble 12 months from now, I'll be pretty PO'ed at myself. I've already wasted too much time on this debacle.
The other option is going with a Google Pixel. I'm frustrated, because I missed that recent Woot! deal on the Google Pixel that ran a few days ago. They all sold off in less than a day. Refurbished Pixel phones with 32Gb ($200) and 128Gb ($244) sizes. I'd have sprung for the 128Gb. But the Pixel isn't free of issues. There's a dreaded screen burn-in that happens on some models. Unpredictable. And when it does, it's a PITA to replace the screen, almost as bad as the HTC 10.
Lastly... I might just say screw-it and stick with my M8 for the next couple of years, until 5G phones with solid electrolyte lithium batteries are available. Phone companies are starting to do customers a disservice with this "sealed in" battery fiasco. Next thing you know, they'll be revoking the Micro SD memory card slot, like Apple.

cytherian said:
Same as you... great value from HTC phones up until the HTC 10 (having skipped the M9).
I'm in a pre-return mode right now with the seller. She has given me the OK to do a return. But I'm going to see if she might welcome the opportunity to do a partial refund. Because if she takes back the phone I don't know if she's going to try reselling it or give it to a family member to deal with. It's a hassle selling a phone that has problems. My thought is, if I can work out a good price (like half the cost of a typical charge--got two quotes for $140 and $150), I'll go ahead and try to do the battery change myself. But then... I'm a little unsure about jumping down that rabbit hole. It may work fine, but I usually keep a new (to me) phone for at least 2 years. If I'm having battery trouble 12 months from now, I'll be pretty PO'ed at myself. I've already wasted too much time on this debacle.
The other option is going with a Google Pixel. I'm frustrated, because I missed that recent Woot! deal on the Google Pixel that ran a few days ago. They all sold off in less than a day. Refurbished Pixel phones with 32Gb ($200) and 128Gb ($244) sizes. I'd have sprung for the 128Gb. But the Pixel isn't free of issues. There's a dreaded screen burn-in that happens on some models. Unpredictable. And when it does, it's a PITA to replace the screen, almost as bad as the HTC 10.
Lastly... I might just say screw-it and stick with my M8 for the next couple of years, until 5G phones with solid electrolyte lithium batteries are available. Phone companies are starting to do customers a disservice with this "sealed in" battery fiasco. Next thing you know, they'll be revoking the Micro SD memory card slot, like Apple.
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Click to collapse
Yeah, I'm thinking to hold on to the device. Thought same that I'd try to sell it, but a hassle. Plus I'm still not convinced its hardware yet. I still kind of feel like its something to do with latest Oreo firmware. Possibly Nougat as well. I'm starting to research downgrading via S-on to Nougat or Marshmallow and just leave it that way if the battery returns somewhat normal. While its a pain to do downgrade, its something I'd consider when I have more time. However, if this was my only device, or main device, then I'd probably cut my losses with it.
Tell you one thing, certainly makes me appreciate the M8 much more than i did!

gustav30 said:
Yeah, I'm thinking to hold on to the device. Thought same that I'd try to sell it, but a hassle. Plus I'm still not convinced its hardware yet. I still kind of feel like its something to do with latest Oreo firmware. Possibly Nougat as well. I'm starting to research downgrading via S-on to Nougat or Marshmallow and just leave it that way if the battery returns somewhat normal. While its a pain to do downgrade, its something I'd consider when I have more time. However, if this was my only device, or main device, then I'd probably cut my losses with it.
Tell you one thing, certainly makes me appreciate the M8 much more than i did!
Click to expand...
Click to collapse
Marshmallow has been a decent version of the Android O/S. You can really spruce it up nicely with different themes. I recently revised the theme on my M8 and it's super. It's just a very dependable phone. And when you get used to that, it's a shock to run into the mess of other phones. Pretty stunned to see all the troubles that the Pixel encountered. Apparently the Pixel-2 has some pretty serious challenges as well, like screen burn-in. I'd never even thought of rolling an HTC 10 back to Marshmallow. Is that really possible? It may not be necessary... as it could all come down to the kernel Go S-OFF and load up a replacement like ElementalX.
So I did a complete factory reset on the phone as I prepped it for returning to the seller. What a pain in the butt... having to wait for the initialization. Took over an hour to complete. Anyway, I made the mistake after initialization and before configuring an account to do the 3-button power cycle. Apparently that wipes all preparation cache, so it had to go through it yet again. After that, I did the cycling 3 times from 99% and it dropped only 1% each time. Baffling. I rebooted several times after that, expecting to see a repeat of that 35~40% drop. Stayed in the high 90's. So with that mystical "recovery" I ran the HTC battery test... and it did just as poorly as before. Definitely something out of whack between the O/S and battery.
I really wish there was a definitive explanation for this. If battery replacement was guaranteed to eliminate it, then I'd feel more comfortable going with a battery change. Would just hate to get burned 12 months later, finding the same issue repeat.

cytherian said:
I'd never even thought of rolling an HTC 10 back to Marshmallow. Is that really possible? It may not be necessary... as it could all come down to the kernel. Go S-OFF and load up ElementalX.
Click to expand...
Click to collapse
You can, also flash a kernel..... WITHOUT being s-off, s-off has never been needed to change kernel. Please elaborate and stop giving false info.
Thank you.

cytherian said:
Marshmallow has been a decent version of the Android O/S. You can really spruce it up nicely with different themes. I recently revised the theme on my M8 and it's super. It's just a very dependable phone. And when you get used to that, it's a shock to run into the mess of other phones. Pretty stunned to see all the troubles that the Pixel encountered. Apparently the Pixel-2 has some pretty serious challenges as well, like screen burn-in. I'd never even thought of rolling an HTC 10 back to Marshmallow. Is that really possible? It may not be necessary... as it could all come down to the kernel. Go S-OFF and load up ElementalX.
So I did a complete factory reset on the phone as I prepped it for returning to the seller. What a pain in the butt... having to wait for the initialization. Took over an hour to complete. Anyway, I made the mistake after initialization and before configuring an account to do the 3-button power cycle. Apparently that wipes all preparation cache, so it had to go through it yet again. After that, I did the cycling 3 times from 99% and it dropped only 1% each time. Baffling. I rebooted several times after that, expecting to see a repeat of that 35~40% drop. Stayed in the high 90's. So with that mystical "recovery" I ran the HTC battery test... and it did just as poorly as before. Definitely something out of whack between the O/S and battery.
I really wish there was a definitive explanation for this. If battery replacement was guaranteed to eliminate it, then I'd feel more comfortable going with a battery change. Would just hate to get burned 12 months later, finding the same issue repeat.
Click to expand...
Click to collapse
Looks like you can downgrade to Nougat or Marshmallow based on this thread here. Can do it remaining S-On.
https://forum.xda-developers.com/htc-10/how-to/how-to-rollback-oreo-to-marshmallow-s-t3787101
Sent from my HTC 10 using Tapatalk

Mr Hofs said:
You can, also flash a kernel..... WITHOUT being s-off, s-off has never been needed to change kernel. Please elaborate and stop giving false info.
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Click to collapse
It wasn't my intention to give false info. I had the impression from what I'd read that making changes at that level required it. But you've obviously got a tremendous amount of experience so I'll revise my understanding. Thank you.

Any real solution for typical HTC battery problem, shutdown at 40%/30%/20%?

Hi,
I bought M8 because I liked good old M7 so much.
So that phone and it's battery are quite new, about a two months old. But I'm bit pissed because there's that same damn battery problem that we have with M7. Phone shutdowns suddenly with random % while batt is below 40% or below 30%.
After that when I restart the phone it shows there's only 2% left. So something with batt calibration is badly wrong.
I've read about it and internet is full of complains and questions but there's no working solution.
So my question is, have anybody found why it's doing that and is there any solution/fix that REALLY works? Or is everybody just living with that fact that HTC only allows to use 60% of phone's battery?
Now it's bit frustrating to use the phone because SOT is at most 2.5h even with light use and if gaming.. well you got the point.
Phone is fully unlocked and rooted with newest twrp. I have had stock MM rom, RR oreo rom, XenonHD oreo rom, ICE 8.2.2 MM rom and now I'll have AOKP nougat rom but same thing with all roms with couple weeks test period so it's not rom depending.
I have searched this forum, other forums etc and tried to find solution.
I have tested official two minutes power+up+down and also that alternative "at least six restarts with power+up+down and then use it empty" - method without any help.
I have tried wiping caches and I have flashed rom/did factory reset while batt is 100%.
I have drained the phone from 100% to as low as it goes(and shutdowns) and then charged back to 100% with phone on and also with phone off.
I have also tried that while it shows it's 100% wait till it drops to 99%, then shutdown the phone and charge again to 100% (because while I plug charger again it shows something between 90% and 99% while shutdown).
I also tried some batt calibration tool from market even I don't believe on them and read that google worker story about these calibrations.
But about that question, any solution? Any help? Anything else to try? It's very good phone and pity there's that problem in such a good phone. But I just don't believe it's faulty battery because it's so common problem.

Flashing a ROM with the default wipe (data, cache, Dalvik) will normally wipe battery stats and recalibrate the battery meter, in my experience. Then reset the high/low flags by charging to 100%, then drain to close to shutdown (10-20%) and that should be it. Intentionally draining to shutdown is not advised nor necessary. But in your case, may be unavoidable as it may be shutting down even as you try to get "close".
The button combo (power+vol up+vol down) to recalibrate the meter doesn't hurt either. But it looks like you've tried all these things, to no avail.
Make sure your firmware is up to date (MM). But I'm guessing that is already the case, as you probably wouldn't able to flash or run the ROMs mentioned, with outdated firmware.
Only other thing I can think, is to flash stock RUU (if your version has one) to return to full "factory" baseline and start over again (then TWRP, ROM of your choice, etc.). But I don't suspect this will help much over what you've already tried. More of a "doesn't hurt to try" suggestion, as long as you have to time/energy to do so.

Thanks for your reply. Stock rom is MM so I think firmware etc should be fine.
And yes, think I've tried almost "everything" but now after I've tested few weeks I noticed something. It seems it's maybe somehow kernel thing. Not sure but if I use stock MM rom batt works just fine. If I use Revolution HD 53.1 MM rom with stock base(?) kernel, batt works quite fine. But right after I flash elementalX to those or use some other MM/Nougat/Oreo rom with other than stock base kernel batt shut down randomly below 40% and shows wrong %. Weird. I think I just stick with Revolution HD and stock kernel since it seems to work and is much better than stock rom.

Mine sometimes shutdown @60
I jst got another one 2days ago
So I sud be expecting same problem?
I noticed this problem after I flashed RR ROM last December, maybe I sud nt use custom ROM @All on this new one
But I am in love wit lineage 16 ROM
Advice pls

I had the same problem over a year ago. Phone would randomly die once the battery went below 30%. I tried every piece of battery recalibration voodoo posted on this and other sites –including ones that were supposedly official HTC recommended ones.
Nothing worked.
In the end, I bought a replacement battery off eBay and fitted it. I think it was about £17 and I haven't had any random shutdowns since. My battery can run right down to 1% now without the phone switching off. I think, at the end of the day, a new battery is the only solution
BTW –the battery I bought looked OEM. Same markings, holograms, etc. But was a fraction of a mm thicker than the old one, so that it was quite a squeeze fitting the phone back together again and I've still got a slight ridge around the edge of the screen where it's not quite sitting flush with the backplate. But, given the HTC One M8 isn't designed to be taken apart in the first place and I pretty much mangled the speaker covers trying to persuade them to come off, using a hot air gun, that's just one more minor cosmetic detail. My phone may look like it's done a couple of rounds with Mike Tyson now. But for £17 it's been given a new lease of life and [hopefully] I'll get another couple of years out of it.