HTC One M9 battery is dying...dead


New member
Aug 29, 2013
I purchased two brand new in box Not refurbished HTC One M9 (T-Mobile) from Amazon in May of 2017. My carrier is Simple Mobile which is a MVNO of T-Mobile. One phone is for my use and the other for my son. My previous device was a HTC One M7.

Right out of the box the battery performance was a bit disappointing. My M7 could last a whole day but the M9 lasts about 4-5 hours max on moderate usage which is mostly browsing, calls, text, whatsapp.

Within three months the battery went from last 4-5 hours to only 2 hours. Basically, any time the battery indicator reaches 40% it powers down.

This gets progressively worse and worse. At this moment, eight months after initial purchase, the phone will power down when it reaches 82% power. This translates into about 20 minutes of usages per full charge.

I have contacted HTC by email twice since the phone is still supposedly under the original 1 year warranty, but no response from HTC. However when I go to one of those IMEI checker and typed mine in, it shows the warranty period is over, and was over BEFORE I even made the purchase.

While I have been struggling with this, my son's phone - identical model, identical carrier, seems to run fine. He gets about six hours out of it, so the theory is my particular device may be defective. Then last week, out of the blue, he told me his phone shuts down suddenly at 30% for no reason, and on powering back up it shows 4% battery. So it seems his phone is having the early stage of the same issue, only it's not as bad as mine, YET.

I have the stock phone, that came with Android version 7.0, security patch level 2-1-2017, software number 4.27.531.6.

I have done a few things so far to get some clarity of the problem.

(1) I have tried charging it with the phone on vs phone off, didn't make a difference.
(2) I have rebooted to safe mode, and it appears the battery drain (which runs about 1+% a minute with no active usage) is the same.
(3) I have tried the battery recaliberation steps by powering off then holding the volume up + down + power buttons for two minutes plus and that didn't seem to make any difference, although the instructions said to turn off "fast boot" which on my phone under Power settings > Battery I do not have such an option.
(3) I have wiped the partition cache when the battery was fully charged at 100%, and after the partition charge the phone reboots to 73%. Not sure I understand what happened here, unless the actual process to wipe the partition cache drained 27% of the battery. I then recharged it to 100%, and the problem persists. Super quick drain, and shuts down once reached 80%, Basically, once it reaches 80% battery level, it shuts down, if you then plug in the charger, the battery says 0%.

I contemplated ordering a new M9 battery, but looking at the youtube video on the process, I am not at all confident that I can do it without damaging the phone itself.

I have to admit, I have not been careful to always use the OEM HTC charger and cable. I have been using HTC for a long time, and have the older charger from S1, M7, M8, various charging cables from an assortment of power banks, and didn't think twice about always charging with original cable and charger. Also, I typically leave the phone charging overnight when I go to bed. My car has a few USB ports and at times I would plug that into my car's USB port to charge if battery level is low. I have a few receptacles in the office with those USB sockets, and again I plug in to charge, not even sure what output amps and voltages of those are. I never had to charge while driving or in the office for older HTC phones as they last the whole day, the M9 I was charging in mid day and more and more. Looking at the charger I used the most it says the output is 5V 1.8A. I know my son uses the OEM charger most of the time.

The questions I have are:
(A) Does this seem like a software issue or hardware issue? Could my charging it with non M9 chargers damaged something?
(B) Is it a waste of time to continue to pursue with HTC a warranty claim to try and get my phone (and possibly my son's phone if it continues to degrade) serviced?
(C) Should I try to swap out a new battery? By myself or by a local phone repair shop? I am fairly handy but the process involved prying teasing loose some glued on parts that just doesn't seem it was designed to be serviced.

Thanks in advance for any comment.