Develop Bugs

Found possible proper battery Calibration for mango Update beta

After updating my HTC HD7 to mango update Beta, i found the battery draining faster than Nodo. With Nodo a proper HTC soft reset could do the trick sometimes but the soft reset does not seem to calibrate the battery. On HTC website its stated that "Perform a soft (normal) reset to clear all active program memory and shut down all active programs. This is useful when your phone is running slower than normal, or a program is not performing properly....". Nowhere in the htc website says soft reset calibrates battery, what it actually does is fresh boot up of OS
here is what i found out after days of experimenting
the battery indicator is inaccurate because mango changed the core OS
to a new one probably screwing up the battery indicator too. if u expereince unusual short battery life while during usage, or in standby with push and radios oN. The battery indicator is overestimating and showing 100% when it could probably be 50 % or some other value. Hence the reason why the battery is being used up faster because its not showing the real charge. Imagine u take a container and fill up to to 50% only and some kind of indicator show that its 100%. indicator tries to catch up with the false reading as the battery drops in usage hence giving the scenario of battery draining faster than usual. So the solution is not to charge it repeatedly to 100% because the charge indicator will still show as inaccurate since the circuitry cuts of charging at 100% indicator and shuts down at 0% with the false reading range. Many references recommend to charge the battery overnight for 8 hours or so., or leave it to trickle charge ect This is wrong because this works only for fresh new batteries that are not "primed"
I let the phone drain fully until it cannot turn on and charged to 50% and it noticed it seem to last longer or just as good as NoDO. thinking that something is amiss or altered here, i then let it go to
1 % Then charged it back to 100%. U should notice that full charging will take longer than usual. Around 2 hours ++.
1) Fully drain the battery till the phone shuts off
2) Charge the battery to 50%
3) run down the battery to 1%
4) Fully charge it to 100%
5) repeat the procedures 3) and 4) a few times for the next few days whenever its possible and follow the same routine every time u charge
Here is a diagram explaining how i came to the conclusion. Report back if the battery life has improved for u
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My phone doesn't shut off when it's fully charged you may want to explain that one better
Sent from my arrive using XDA Windows Phone 7 App

kwajr said:
My phone doesn't shut off when it's fully charged you may want to explain that one better
Sent from my arrive using XDA Windows Phone 7 App
Click to expand...
Click to collapse
Why does it need to shut off?

I also found that the battery seemed to drain pretty quick. But this sounds logical. I'll test you method and report back.

Some where r all over the place , its stated that many devices using lithium ion have battery indicator problems .
Maybe this s the problem.

What did you edit in your op
Magpir said:
Why does it need to shut off?
Click to expand...
Click to collapse
Sent from my arrive using XDA Windows Phone 7 App

anyone have improved battery life in this method??

I suggest to read this or this and this before you exercise this procedure. Here are the main points:
- A Li ion battery loses about 20% capacity per year if fully charged at typical average temps of 25C. It only loses 4% if charged to 50% (all of this highly temperature dependent).
- Li ion batteries have no memory effect (holding less charge)
- completely draining a Li ion battery is bad (if you let it sit in this state you may end up with a dead battery)
- shallow discharges are best (let the battery drain to 15-20%, then recharge)
in summary, the more you stress the battery by charging/discharging the sooner it will see its end of life. The best is to keep it at values of 50-60% charge. Of course this is not always practical (trips etc), just try not to always push it to 100% if possible.
if you think the OS/battery indicator interprets the battery level incorrectly, that is a whole different story of course and would be a major flaw (and could be manufacturer dependent). I did not see any difference between NoDo and Mango on mine.

My method is not deep discharging the battery. Its to calibrate the indicator as seems that the os is controlling the indicator

Also do note that one yr phone comes new, ita battery is charged to 40% only.

Basically there's a sensor in your phone that is used by your phone to tell how full/empty the battery is.
This sensor doesn't actually know how full your battery is, all it knows is how much power is coming from your battery at the time. The problem it has is that all batteries are slightly different, and their capacity goes down over time and usage (a three year old battery will not be able to hold as much charge as a brand new battery).
Your phone keeps a record of the maximum power it's ever had from the battery, as well as knowing the minimum power that it can safely work with before it has to turn itself off. It uses the difference between those two numbers, and the current power at any time to calculate how much percentage of your battery you have left at that time. So with a new battery, the phone might be telling you that the battery is fully charged because it's charged to the highest level the phone's ever seen, but if you leave it charging a bit longer then it might charge more, and then the phone can recalibrate itself and use this new value as the most it's ever seen.
You should only need to do this "over-charging" with a brand new phone/battery, after that the phone know the maximum values, and can more accurately tell you when it's full.

The correct way is to charge it from 1% always once its calibrated.

derausgewanderte said:
I suggest to read this or this and this before you exercise this procedure. Here are the main points:
- A Li ion battery loses about 20% capacity per year if fully charged at typical average temps of 25C. It only loses 4% if charged to 50% (all of this highly temperature dependent).
- Li ion batteries have no memory effect (holding less charge)
- completely draining a Li ion battery is bad (if you let it sit in this state you may end up with a dead battery)
- shallow discharges are best (let the battery drain to 15-20%, then recharge)
in summary, the more you stress the battery by charging/discharging the sooner it will see its end of life. The best is to keep it at values of 50-60% charge. Of course this is not always practical (trips etc), just try not to always push it to 100% if possible.
if you think the OS/battery indicator interprets the battery level incorrectly, that is a whole different story of course and would be a major flaw (and could be manufacturer dependent). I did not see any difference between NoDo and Mango on mine.
Click to expand...
Click to collapse
What this guy said. I haven't seen a big change in battery performance either, at least on really intensive tasks like web browsing (at least on my phone). Other than that it seems to discharge a lot slower. On the other hand, I'm wondering if all feedback I'm sending back to Microsoft is having some impact. Perhaps I'll turn those off to see how it performs.

ScottSUmmers said:
What this guy said. I haven't seen a big change in battery performance either, at least on really intensive tasks like web browsing (at least on my phone). Other than that it seems to discharge a lot slower. On the other hand, I'm wondering if all feedback I'm sending back to Microsoft is having some impact. Perhaps I'll turn those off to see how it performs.
Click to expand...
Click to collapse
the battery performance is
dependent on the battery capacity.
Calibration helps to maximize the phone battery capacity without the indicator shutting it off prematurely.
imagine yr car has a petrol indicator which is wrong and it shuts off yr car because it thinks that the petrol is used up
but u still find that there is a good amount of petrol left but the car is not using them because of the indicator which shuts down the car prematurely

Magpir said:
the battery performance is
dependent on the battery capacity.
Calibration helps to maximize the phone battery capacity without the indicator shutting it off prematurely.
imagine yr car has a petrol indicator which is wrong and it shuts off yr car because it thinks that the petrol is used up
but u still find that there is a good amount of petrol left but the car is not using them because of the indicator which shuts down the car prematurely
Click to expand...
Click to collapse
Again, if you assume the Mango OS interprets the battery circuit wrong (controller IC built into battery), then something is utterly wrong of course and needs to be addressed. I have not seen many people here having problems with battery life that would be alarming. This should also be manufacturer dependent as the battery status is first interpreted by the phone's hardware before it goes to the OS....
my two cents...

derausgewanderte said:
Again, if you assume the Mango OS interprets the battery circuit wrong (controller IC built into battery), then something is utterly wrong of course and needs to be addressed. I have not seen many people here having problems with battery life that would be alarming. This should also be manufacturer dependent as the battery status is first interpreted by the phone's hardware before it goes to the OS....
my two cents...
Click to expand...
Click to collapse
there are in fact alarming battery problems in wp7 phones.
do a quick google.

Magpir said:
the battery performance is
dependent on the battery capacity.
Calibration helps to maximize the phone battery capacity without the indicator shutting it off prematurely.
imagine yr car has a petrol indicator which is wrong and it shuts off yr car because it thinks that the petrol is used up
but u still find that there is a good amount of petrol left but the car is not using them because of the indicator which shuts down the car prematurely
Click to expand...
Click to collapse
No I understand what you're saying, and I've done calibrations before. However, I was just quoting derausgewanderte as a warning that letting it discharge to 0% will decrease the life of your battery faster. If it's of no concern to you by all means.

Yes my method did not advocate draining to 0% multiple times. Only once as regular calibration routine

Magpir said:
Yes my method did not advocate draining to 0% muryople times. Only once as regular calibration routine
Click to expand...
Click to collapse
1% - 0%: how would you be able to tell the difference if your argument is that the indicator reading is wrong?

derausgewanderte said:
1% - 0%: how would you be able to tell the difference if your argument is that the indicator reading is wrong?
Click to expand...
Click to collapse
scroll up and read my first post.

doze at night

My doze doesn't seem to be activating at night. Moto display turned off. I'm losing about 10% while sleeping which seems like a lot considering my s8 plus lost about half that with always on display on...

I'm also losing about 7% per hour and getting about 3hrs screen time per charge. I noticed a decrease in efficiency possibly after buying and using the Incipio wireless charging battery moto mod.

You can't judge battery drain from 100-90% once it goes below 88% that is when you get true readings. If you unplug your phone at the high 90's the charging algorithm could have had it at 92% and over those hours it just equalized itself.
I.E. I had my phone at 99% charge on the charger for an hour or two while using. The phone will still show 99% but the battery isn't getting a trickle to stay at 99% it will not get power and drop to roughly 91-93% depending on kernel then charge back up to help battery longevity but the system will still show 99% to not make the average user freak out over their battery level dropping while charged. There was a in depth post about this years ago on this site. Too lazy to search and post, but it is a simple search.
Edit: here you go, found it. It's a great read.
https://forum.xda-developers.com/showthread.php?t=871051

It is a good read but not really what I am talking about. I never leave my phone on my charger at night. I charge to 100% before I go to sleep and sometimes I use for hour or two before bed. So the drain I am experiencing can't really be related to a false reading due to changing currents after a long time on the charger. Sometimes it's down to 70-80% by time I go to sleep and I am still losing that amount in drain. Dozing doesn't appear in my charts at all at night so it appears the phone is never truly dozing... But hey, I'm not a genius about all this, I just know it's not dozing and my cycles in gsam suck for an 835 processor phone even taking into account the smaller battery.

My buddy just made a good point... If I am sleeping with the battery mod connected, even if it's not "charging" maybe the connection makes the phone"think" it's charging and not doze? I'll have to test that tonight.

Chrisy8s said:
My buddy just made a good point... If I am sleeping with the battery mod connected, even if it's not "charging" maybe the connection makes the phone"think" it's charging and not doze? I'll have to test that tonight.
Click to expand...
Click to collapse
That makes sense and I was just going off the image showing 100-92 drain. I wouldn't have a mod on if you're not using it, it can cause drain.

Excessive battery drain immediately after unplugging from charger?

So I've noticed some weird battery behavior on my Pixel 2 XL and was wondering if anyone else has noticed this.
I normally like to ;et the battery drain down into 5% or so before plugging it in and letting it charge through to 100%. I started noticing that a full charge would take me nearly 2 hours fully charge. A couple of times last week, I had to step out and the phone was charged approximately 95%. I unplugged the charger and walked to my car (about 5-6 minutes to get to the car) and when I looked at my phone, charge had dropped to 88%. Over the next few days I noticed this kind of excessive drain immediately after unplugging the charger. Aside from this, I still achieve 24+ hrs of battery life on a single charge so I am not sure that it is a HUGE issue, but one I felt shouldn't be happening nonetheless. Last night the same happened - unplugged around 95% and i literally saw the battery indicator go to 93%, 91%, 88% and then stop at 87% in about a minute. I immediately called Google support, shared my screen, and after speaking with the person on the phone - i was told I should definitely RMA, which i did..so I have a replacement coming.
I don't use always on display or always listening and I am extremely good at clearing open apps before I put the screen to sleep. I have noticed this at home, on my wifi as i always need a charge later in the day when I'm home from work. Also, I use the OEM charging wire and brick.
Anyone else notice this ?

I have not noticed battery drain fast after unplugging at full charge level. I would say you probably should RMA the device. Also it is not good to let lithium-ion batteries go down to low levels a lot like that, it will degrade the battery faster. The less you let the battery go down to low levels, the more charge cycles you will have, which means long battery life over time.

raidflex said:
I have not noticed battery drain fast after unplugging at full charge level. I would say you probably should RMA the device. Also it is not good to let lithium-ion batteries go down to low levels a lot like that, it will degrade the battery faster. The less you let the battery go down to low levels, the more charge cycles you will have, which means long battery life over time.
Click to expand...
Click to collapse
I definitely did RMA, it was a painless process.
And I always thought that maximizing the charge of the phone (letting it get low, then charging up) would actually keep the battery healthier as it would reduce the # of times I charged it. Am i way off base with my logic for that?!

Going into my third week with my 2 XL and I haven't seen anything abnormal regarding battery drain.
I do practice the method of unplugging at 85% and plugging back in around 15% (per Accubattery's reco, and other reading done online)....
There's no proof that it helps as suggested, and while I realize that only allows me access to 70% of the battery's charge potential, I'm rarely, if ever, away from a plug for more than half a day.
This theory worked well in my 6P until it got the intermittent BLOD... My battery health was around 84% (via Accubattery) after 17 months of pretty heavy use.
Again, not sure it is solid fact or not, but you could always try it for a month and see if there is any noticeable difference in battery drain.

Thank you for that insight! I will absolutely do some research. You're battery health after 17 months is really impressive. I just switched from a Nexus 6p that was definitely showing signs of wear after 2 years of fairly standard use. I hadn't used accubattery, but I will download it on my new replacement and monitor results.
I will say though, that aside from that slight blip i noticed - the battery (andOS optimization i'm assuming) is amazing. I get through a day plus easily. So, anything I can do to keep that consistent or squeeze more time out of it is a no brainer.
Az Biker said:
Going into my third week with my 2 XL and I haven't seen anything abnormal regarding battery drain.
I do practice the method of unplugging at 85% and plugging back in around 15% (per Accubattery's reco, and other reading done online)....
There's no proof that it helps as suggested, and while I realize that only allows me access to 70% of the battery's charge potential, I'm rarely, if ever, away from a plug for more than half a day.
This theory worked well in my 6P until it got the intermittent BLOD... My battery health was around 84% (via Accubattery) after 17 months of pretty heavy use.
Again, not sure it is solid fact or not, but you could always try it for a month and see if there is any noticeable difference in battery drain.
Click to expand...
Click to collapse

AceKingNYC said:
I definitely did RMA, it was a painless process.
And I always thought that maximizing the charge of the phone (letting it get low, then charging up) would actually keep the battery healthier as it would reduce the # of times I charged it. Am i way off base with my logic for that?!
Click to expand...
Click to collapse
Lithium-ion batteries work on charge cycles and are happier between 50-85% charge levels. You cannot really "overcharge" the battery because the phone will stop charging at 100% and just trickle charge to keep the battery at this level. But unplugging it after full charge defiantly wont hurt. If you keep the battery at higher levels I would't be surprised that you would get 1500+ charge cycl.es out of the phone before any real degradation which should easily get you years of good battery life. I find the battery life on the XL to be awesome and it lasts me throughout the day with still 40% battery life left and that is with pretty heavy usage.

Is this battery behavior normal?

I've noticed that my 2 XL battery drains very fast after full charge, but then settles to acceptable drain rates from about 90%. I'd say it takes less than an hour to drop from 100 to 90% without basically any use. Often I can't even hit 100% when charging. More like 99/98% max. If it does charge to 100%, it stays there for a couple minutes tops, even if just on standby. Which leads me to my next issue...
This prompted me to calibrate my battery which seemed to help somewhat, but I found that I cannot monitor the charge rate when charging while the device is turned off. What is shown is just what "looks like" a full battery charged icon at all times, and the screen does not dim at any point during charge. It actually seems that the phone is frozen during charging when turned off, and needs a very long power button press to turn the phone on. I actually have two Pixel 2 XLs in front of me and they both do this! Is this a known issue?
In general I am getting 5-6 hours screen-on time per charge which seems about right from what I've read. But that initial fast drain and "freezing" while charging when turned off is puzzling. Any common experiences or insight?

nobaddreams said:
I've noticed that my 2 XL battery drains very fast after full charge, but then settles to acceptable drain rates from about 90%. I'd say it takes less than an hour to drop from 100 to 90% without basically any use. Often I can't even hit 100% when charging. More like 99/98% max. If it does charge to 100%, it stays there for a couple minutes tops, even if just on standby. Which leads me to my next issue...
This prompted me to calibrate my battery which seemed to help somewhat, but I found that I cannot monitor the charge rate when charging while the device is turned off. What is shown is just what "looks like" a full battery charged icon at all times, and the screen does not dim at any point during charge. It actually seems that the phone is frozen during charging when turned off, and needs a very long power button press to turn the phone on. I actually have two Pixel 2 XLs in front of me and they both do this! Is this a known issue?
In general I am getting 5-6 hours screen-on time per charge which seems about right from what I've read. But that initial fast drain and "freezing" while charging when turned off is puzzling. Any common experiences or insight?
Click to expand...
Click to collapse
It may be that the battery is not fully charged when the phone is telling you it is 100%. When using Accubattery to manually benchmark the battery, I found that my phones were still taking a low charge current (as measured by AB) for 45 minutes to sometimes even one hour after the phone was reading 100%. AB will register 100% when the phone's charging circuit cuts off to zero (and notify you). Using AB for a while will also give you a very close approximation of the remaining capacity of your battery relative to a new battery. When my 2XL was new, I was getting just over 100% (~103%). A year later, it is in the high 90's.

Thanks for the tip on Accubattery. I am going to give that a try for a while. So have you been charging up to 100% regularly in spite of what's recommended by this app?

nobaddreams said:
Thanks for the tip on Accubattery. I am going to give that a try for a while. So have you been charging up to 100% regularly in spite of what's recommended by this app?
Click to expand...
Click to collapse
Yes, I turn the 80% alarm crap off and leave it on the charger all night. It is fully charged before I go to bed but I leave it on the charger all night. I use AB for bench marking my battery's capacity and it's real good at that... if you start from when AB says your battery is full. You will see it converge to a % capacity after only 2-3 full discharges. I'm just guessing but I think you are not completely filling the battery to it's full capacity. At least using AB for a while will a) provide you with your battery's true capacity wrt a new battery, and b) will rule out you not charging up fully as your mystery 100-90% quick-drop. Please do report back. :good:

Battery hold from 11% to 0%

Hi all,
occasionally I see my 7 months old Pixel 3a XL can't hold battery power from 11% down. Switches off very fast, abnormally fast. Then if I power it and start it then keeps on restarting until battery level is higher than 5-6%
I use the original charger only. Sometimes it appears, some it does not and I can see it discharges as expected.
I try to keep my battery within 40-100% full and discharge it very rarely to 0%.
Anyone facing those abnormalities? Can't think of connected events - updates, etc ....
Cheers
p.s. after last night happening again, charged the phone from 0% to 86% (phone was off during charge), turned on on 86% and left over night on the shelf. Usually drains 2-3%, this morning it dropped from 86% to 62%. All connections off, nothing unusual shown in the battery usage stats...

TodNex said:
Hi all,
occasionally I see my 7 months old Pixel 3a XL can't hold battery power from 11% down. Switches off very fast, abnormally fast. Then if I power it and start it then keeps on restarting until battery level is higher than 5-6%
I use the original charger only. Sometimes it appears, some it does not and I can see it discharges as expected.
I try to keep my battery within 40-100% full and discharge it very rarely to 0%.
Anyone facing those abnormalities? Can't think of connected events - updates, etc ....
Cheers
p.s. after last night happening again, charged the phone from 0% to 86% (phone was off during charge), turned on on 86% and left over night on the shelf. Usually drains 2-3%, this morning it dropped from 86% to 62%. All connections off, nothing unusual shown in the battery usage stats...
Click to expand...
Click to collapse
That's pretty weird
My 3a xl (about the same age as yours) doesn't use more than 10% max when left overnight. Are you using AOD or anything?
Sent from my Pixel 3a XL using XDA Labs

@Skittles9823 nothing beside stock Android and apps that I've used forever. Strange is that it's occasional - also occassional is initial drain from 100% to 92%.
Maybe its time to flash it - nothing suspicious is shown in batt stats
I use the fast charger that came with it. Not sure how it affects battery life long term. I try to keep it 100% to 40% usually and not charge it if not necessary..

TodNex said:
@Skittles9823
I use the fast charger that came with it. Not sure how it affects battery life long term. I try to keep it 100% to 40% usually and not charge it if not necessary..
Click to expand...
Click to collapse
I think popular wisdom is that both fast charging and in particular charging to 100% are not kind to the battery's longivety. Divided opinion about the effect of discharging to low percentages. Personally I charge to between 70 and 80% unless I know I'm going to need more capacity. 3a XL has a bigish battery, which helps. I recharge most nights but only to 70-80%. End of day I usually end up between high 40's and low 30's charge.
I manually set all apps I don't actually need to run in background to 'restricted' background use.

I charge mine up to a 100% often, when using it heavy.. I never heard of charging a battery to 100% being bad for it, unless you believe everything that is told or should I say sold to you.. Sounds like a faulty battery. If still under the 1 yr usual warranty I would have it replaced. I have drained mine down to less than 20% and still never experience any issue that OP state.

doubledragon5 said:
I never heard of charging a battery to 100% being bad for it
Click to expand...
Click to collapse
Some research references in here
https://accubattery.zendesk.com/hc/en-us/articles/210224725-Charging-research-and-methodology
https://accubattery.zendesk.com/hc/...-Cycle-Life-Modeling-of-Lithium-Ion-Batteries
Also Apple have actually introduced a feature to stop/postpone 100% charging when the phone thinks it's not required. Would be good if we had similar/more control for Android.
https://support.apple.com/en-us/HT210512

WibblyW said:
Some research references in here
https://accubattery.zendesk.com/hc/en-us/articles/210224725-Charging-research-and-methodology
https://accubattery.zendesk.com/hc/...-Cycle-Life-Modeling-of-Lithium-Ion-Batteries
Also Apple have actually introduced a feature to stop/postpone 100% charging when the phone thinks it's not required. Would be good if we had similar/more control for Android.
https://support.apple.com/en-us/HT210512
Click to expand...
Click to collapse
I'm still not sold on the idea that charging a battery to 100% is bad.. But thanks for those links.

doubledragon5 said:
I'm still not sold on the idea that charging a battery to 100% is bad.. But thanks for those links.
Click to expand...
Click to collapse
It's actually true. Lithium Ion batters degrade over time, the speed of which, depends on the amount of battery cycles they go through (0-100% and vice versa). Others have done the research and the math and found that generally a 20% to 80% and vice versa charge seems to be the best for longevity.
Personally I charge to 100 but try to charge my phone when it gets to 20-30%.
Sent from my Pixel 3a XL using XDA Labs

doubledragon5 said:
I'm still not sold on the idea that charging a battery to 100% is bad.. But thanks for those links.
Click to expand...
Click to collapse
Evidence and research is there. Of course you don't have to believe it. It's your phone, your battery, your money

WibblyW said:
Evidence and research is there. Of course you don't have to believe it. It's your phone, your battery, your money
Click to expand...
Click to collapse
So very true my phone my money. In all my years of using cell phones, I think I have actually replaced a battery once because it went bad.

Thank you all for the links and the inputs!
One more symptom - when is very low like this morning - 1% and put it in charger - phone shuts off.
I will keep the battery in 40-80% for the future and limit the drain below 40%. I tried to charge it slow with USB - took me like 6-7 hours...
How long it takes you from zero to 100% with the stock charger - looks very fast to me - 0% to 67% in 35 mins
I personally tried to research and could not find what is worse for these batteries - number of cycles (obvious less when used below 40%) or the low capacity usage ?

TodNex said:
Thank you all for the links and the inputs!
One more symptom - when is very low like this morning - 1% and put it in charger - phone shuts off.
I will keep the battery in 40-80% for the future and limit the drain below 40%. I tried to charge it slow with USB - took me like 6-7 hours...
How long it takes you from zero to 100% with the stock charger - looks very fast to me - 0% to 67% in 35 mins
I personally tried to research and could not find what is worse for these batteries - number of cycles (obvious less when used below 40%) or the low capacity usage ?
Click to expand...
Click to collapse
The included charger is a fast charger, good for headlining how fast it charges, not so great for the battery. I just use a 'standard' (Anker) USB charger.
Jury's out on if deeper discharge is bad, but it's the number of complete cycles (0-100% counting as 1). So 40 - 80% is 0.4 of a full cycle, and you're not stressing the battery so much by taking it to 100%. Many folk here replace their phones frequently enough not to be bothered by all this - if they sell it when 20% of the battery capacity's gone, that's fine.

I've observed the behaviour and few things made me question myself...one time I can see 13% battery and palying Youtube just shutdown the phone. Put it into charger and started showing 4% as initial charge.
There was another time when using Viber video shutdown in 23% but can be overheat or software bug.
I try to keep it these days above 40% charge but still use the supplied charger till I buy new slower one.

TodNex said:
I've observed the behaviour and few things made me question myself...one time I can see 13% battery and palying Youtube just shutdown the phone. Put it into charger and started showing 4% as initial charge.
There was another time when using Viber video shutdown in 23% but can be overheat or software bug.
I try to keep it these days above 40% charge but still use the supplied charger till I buy new slower one.
Click to expand...
Click to collapse
The good news is that this phone seems to be pretty easy to repair and a battery replacement could very well be a good option for you, especially since you wouldn't be compromising any water resistance or anything