Develop Bugs

[Explained] Why your battery level drops immediately after unplugging.

Edit: Changed the title to make the answer easier to find. The battery popup killer mod has nothing to do with why the battery level drops after unplugging, as you will learn when you read the linked article. Now, on to my original post...
Pretty much every ROM for the Epic now incorporates the Battery Full Popup Killer mod at this point, but are we sure there aren't any unintended side effects of it? Is the battery charge state still being recorded to the batterystats.bin file? I know when you delete it through a file manager, or reset the stats through CWM, it does regenerate, but there is a lot more info in that file than just the full and empty charge levels of the battery, so it would be regenerated for the other services that use it.
I've had issues with my battery reporting that it's full, but only showing a charge of anywhere between 94-98%. Now, if my battery were actually defective, and losing capacity faster than normal, the batterystats.bin file should be compensating for that by recording the lower full charge level and adjusting the percent reporting accordingly, but it doesn't seem to be doing that.
So, are we sure the state of the battery is being recorded, even though the popup is being blocked? What else could be causing this issue with so many people reporting that their batteries aren't charging to full?

Questions need to go in the q&a section to keep the development section for pure development. Or as a reply on someones thread/rom. Although I have seen this question raised once before on mammons thread I think. I think the answer was that the battery is not set to charge to 100, and some other technictal details I can't remember. But from a day 1 owner of epic, my phone has never charged above 96-98, it will go to 100, but the second I pull it off charger down to 96-98. Even stock, with no mods to the battery popup notification. And now being on a rom that does have that no pop up notification, so I don't have to get woken up from a vibrating phone, there is no change. I'm sure someone else can give you the more detailed explination though.
Sent from my SPH-D700 using XDA App

I forgot that there was a Q&A thread in the development section, sorry to clutter things up. Thanks for the details, I'll see if I can find the Mammon thread that has the same question in it.

Hopefully this gets moved to the proper section as its a good question. Firon and I did some early work on this mod and I can tell you that we simply aimed at the graphical display and then stopped it from reporting. We didn't alter how it reports %s in anyway. I can also say that this issue is found in a stock epic right out of the box. My feelings are that the actual code for charging the battery is done this way on purpose which is lazy and over cautious imho, maybe they were worried about ruining batteries or even having one explode. Sounds like poor project management in any case.
sent by an Epic4g through the cosmos

OK, after searching through the threads for a little while, I found a very good article dealing with this issue.
http://www.androidpolice.com/2010/1...bump-charging-and-inconsistent-battery-drain/
Basically, the battery is supposed to charge to 100%, and then it stops charging to drop the battery level down to a safe level. It will then periodically charge the battery again to maintain a high (but safe) charge level, but never back to 100%. The batteries used in smartphones today aren't safe to keep at 100%, nor is it good for them (they corrode faster), so the charging system keeps them at a full, but not completely full state during the charging process. The phone will report the battery as being full while plugged in, even though it could be running fully on battery power at that moment and a few percentage points below 100%. It does this to make it easy for regular users to know when their phone is finished charging. It's only when you delve into the details that you start to see that the battery isn't actually fully charged, and start to rip your hair out when trying to figure out why it won't do it.
To sum up the entire article, it's supposed to do that. There isn't anything wrong with your battery, or your phone, it's done to prolong the life of the battery, and so the battery won't explode or catch fire by being held at 100% for too long.

The only time my battery meter reads 100% is when I pop a fresh battery in from my external charger.
Sent from my SPH-D700 using Tapatalk

I should have also added in my last post that bump charging does actually work, but will decrease the life of your battery. The experiment that the author of the linked article concluded that bump charging until the phone actually reads 100% while unplugged increased his battery charge by around 15%. Now, if holding your battery at 100% causes premature corrosion, it only makes sense that holding it at 115% causes corrosion at a greater rate.
If you absolutely must get the most time out of your battery, and are willing to buy a new one later on, go ahead a bump charge the **** out of that battery. The author suggests (and sites battery university as a source) that the best way to go about battery charging is to do several short charges throughout the day, rather than 1 deep charge from 0 to 100%.
Also, the author suggests that you stop obsessing on what the reported charge is telling you, and just use your phone.

Still makes no sense. They could code it to say 100% when its at 95% then so we atleast have the impression that its as full as could be safely. Like I said, over cautious and lazy imho...
sent by an Epic4g through the cosmos

Yeah, I suppose it is, but then it wouldn't be accurately reporting the battery level, which I guess is what Android's goal is. Personally, I'd prefer that if 95% is as much as I'm going to get out of a charge, than Android should just lie to me and tell me it's 100%.

mattallica76 said:
The only time my battery meter reads 100% is when I pop a fresh battery in from my external charger.
Sent from my SPH-D700 using Tapatalk
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same here, was going to say this as well.

yogi2010 said:
same here, was going to say this as well.
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I wonder if that's because the charge process brings the battery to 100% initially, then stops charging. Since the battery is in an external charger, there's nothing to draw power from it, so when it hits 100% and stops charging, it remains at 100% until there's a draw on the power.
I'm curious as to whether or not the user guide for the external charger mentions anything about not leaving your charged battery sit for a certain length of time. Based on the linked article, it's claimed that keeping the battery at 100% is damaging to it.

Migital Warfare said:
I wonder if that's because the charge process brings the battery to 100% initially, then stops charging. Since the battery is in an external charger, there's nothing to draw power from it, so when it hits 100% and stops charging, it remains at 100% until there's a draw on the power.
I'm curious as to whether or not the user guide for the external charger mentions anything about not leaving your charged battery sit for a certain length of time. Based on the linked article, it's claimed that keeping the battery at 100% is damaging to it.
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that's probably true about there not being anything to draw power when it's in the ext. charger. the funny thing is, I will pop in the fresh battery, and it will boot up the phone, and I can even do a several things, and the battery will still be at 100!
I try to take the battery out of the charger as soon as possible once it hits full charge, but I'm not always able to. I don't think there were any instructions wth the charger.... the whole thing was prety minimal: I paid my 12 bucks, or whatever, and never heard from them at all, until 2 weeks later an envelope arrived from China, containing only a charger and 2 batteries, lol.

I have both the Samsung OEM battery charger that they sell in the sprint store, and the cheepo Hong Kong charger that comes with knock off batteries. They both stop charging when the chip in the battery says it's full. Neither one had any documentation. I've seen zero negative effects from leaving any of my 5 oem batteries fully charged for long periods of time. The two knockoff batteries I had both died permenantly after about a month.
Sent from my SPH-D700 using Tapatalk

mattallica76 said:
I have both the Samsung OEM battery charger that they sell in the sprint store, and the cheepo Hong Kong charger that comes with knock off batteries. They both stop charging when the chip in the battery says it's full. Neither one had any documentation. I've seen zero negative effects from leaving any of my 5 oem batteries fully charged for long periods of time. The two knockoff batteries I had both died permenantly after about a month.
Sent from my SPH-D700 using Tapatalk
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dang, i guess i've had better luck with the cheapos.... been running them daily for over 2 months, and can't tell any difference between them and the Samsung battery that came with the phone.

yogi2010 said:
dang, i guess i've had better luck with the cheapos.... been running them daily for over 2 months, and can't tell any difference between them and the Samsung battery that came with the phone.
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When they worked, they worked great. But one day I charged one up and stuck it in my pocket. When I stuck it in my phone, i got nothin. I took it home and put it back in the charger and the indicator light said it was fully charged but it was completely bone dead. Wouldn't take a charge at all. Same thing happened to the other one a couple weeks later. I have yet to have any problems with the oem batteries.

really nice article and it actually makes me feel a lot better. i thought it was attributed to certain ROMs somehow as i feel like i picked the phone up at 100 and it stayed there on some but not others. guess that was all placebo, lol. i think hte best part of the article is right at the end:
If you are someone who can top off your phone on a regular basis, do it. Plug it in when you’re at home. Plug it in when you’re at your desk. As explained by Battery University, "Several partial discharges with frequent recharges are better for lithium-ion than one deep one. Recharging a partially charged lithium-ion does not cause harm because there is no memory."[2]
peace

Thanks for the informative thread

Battery Life Bug - Heads Up

Initially, I was very surprised and pleased by the battery life of this phone. I charged it on Saturday, and my usage since then took it down to about 73% this morning. 32 hours of use and 27% battery drain? I'll take that!
But something weird happened today. About midway through the day, the battery just started to crater. Worse yet, charging didn't do anything! The charging indicator animated, but battery life was still falling precipitously. I used it constantly on the train this morning, so I get why it was at 58% by the time I got to work, but then from 8am to about 2pm, it went down to 30%. Then from 2pm to 3pm while it was "charging", it went down to 18%.
Of course I googled the hell out of this, and came across this thread
And rebooting the phone magically stopped the battery drain, and allowed it to start charging again. So I guess our SGSII's are just like the international ones in that regard. Apparently some ROMs have fixed this, but we're still a little new to benefit from that approach. So, just a heads up: if your battery chart just starts falling into the floor, reboot and all will be well.
Note: this also explains the "Android OS" entry showing up at the top of your battery charts. I was shocked when 2 hours of display only accounted for 22% of my battery usage, while Android OS was 68%. Apparently the suspend mode goes insane sometimes and the process of attempting and failing to sleep the phone sucks the battery dry. I'd say that's pretty ironic, myself.

This happened to me also. I was not even touching my phone while working today and it beeped saying 50% I'm like wtf? So I let it sit still working and it beeped saying it needs to be charged. Crazy but I sure do hope this helps and is fixed soon.
Sent from my hand crippling Epic 4g Touch

happened 2 me couple times, i thought some app was keeping my phone from going to sleep. so i tried spare parts, spare parts doesnt work on stock gingerbread roms on samsung... so i cudnt figure out wat was going wrong... because lets say my battery was at 80%, after i reboot, it would be at 55%, just with a reboot...
i figured something was going wrong in the background, and the battery stats are not reported correctly, your REAL battery percentage shows right when you reboot...
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after i rooted the phone, THIS FREAKING EXACT PROBLEM made me do a factory reset on my phone, which put my phone in a boot loop... after waiting 16+ hours for a stock kernal to come out, i had to brick my device on purpose (so sprint could not even turn it on), and dey gave me a new SGSII... if i didn't brick it, they would have known it was rooted, due to the international splash screen...

trifthen said:
Initially, I was very surprised and pleased by the battery life of this phone. I charged it on Saturday, and my usage since then took it down to about 73% this morning. 32 hours of use and 27% battery drain? I'll take that!
But something weird happened today. About midway through the day, the battery just started to crater. Worse yet, charging didn't do anything! The charging indicator animated, but battery life was still falling precipitously. I used it constantly on the train this morning, so I get why it was at 58% by the time I got to work, but then from 8am to about 2pm, it went down to 30%. Then from 2pm to 3pm while it was "charging", it went down to 18%.
Of course I googled the hell out of this, and came across this thread
And rebooting the phone magically stopped the battery drain, and allowed it to start charging again. So I guess our SGSII's are just like the international ones in that regard. Apparently some ROMs have fixed this, but we're still a little new to benefit from that approach. So, just a heads up: if your battery chart just starts falling into the floor, reboot and all will be well.
Note: this also explains the "Android OS" entry showing up at the top of your battery charts. I was shocked when 2 hours of display only accounted for 22% of my battery usage, while Android OS was 68%. Apparently the suspend mode goes insane sometimes and the process of attempting and failing to sleep the phone sucks the battery dry. I'd say that's pretty ironic, myself.
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Had you installed anything that could have caused this?

Mine was plugged in all night and said 100% then froze this am and dropped to 10% after reboot
Sent from my SPH-D710 using XDA App

i was having the same issue at work eariler today

chrisnosleep said:
Had you installed anything that could have caused this?
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No. I haven't installed anything since yesterday, when it was (supposedly) sipping the battery. It just started going nuts this afternoon. That's why I started looking and found that bug thread for the international SGSII. Apparently there was also a bug in 2.3.3 that would cause some widgets to suck the battery dry within hours, while idle and even in airplane mode. So I guess they're moving in the right direction.

I had a weird issue just now. Battery was at 26 percent. Did a reboot by holding the power button down for 8 seconds or whatever it is. When it booted back up about 30 seconds later i had 10 percent battery.
Sent from my SPH-D710 using XDA App

Today is my first day giving this phone a while, and I've been awestruck by the battery life.
Screen on for a large chunk of the past 12 hours that I've owned it, and I'm still showing about 50 percent. I imagine a battery anticipating 4G usage but me having it turned off all the time gives the phone a real edge, lifewise.
Not looking forward to it cratering like you guys have seen.

HOW CAN YOU GET THIS LIFE AND I CANT?????
I hard reset and started over for everything
Should I take it to sprint store?

like it was some what pointed out alot may be due to the charger....i kept my epic 4g charger and have been using that

imtjnotu said:
like it was some what pointed out alot may be due to the charger....i kept my epic 4g charger and have been using that
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I kept my htc evo one, after hearing about screen sensitivity issues and now this.

I got 23 hours with some heavy use on the first charge. It should only get better with the new kernels.
Transmission sent from a Galaxy S II.

so this is 4 out of 4 samsung devices that do this. both galaxy tablets - 7 and 10.1, droid charge and now this. none of my other android tablets or phones do this. the battery just drops with nothing being used. at -2ma usage it goes from 60% to 20% in seconds or from a reboot.

madsquabbles said:
so this is 4 out of 4 samsung devices that do this. both galaxy tablets - 7 and 10.1, droid charge and now this. none of my other android tablets or phones do this. the battery just drops with nothing being used. at -2ma usage it goes from 60% to 20% in seconds or from a reboot.
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That may be the case, but I know from my Droid Eris, that bugs just happen. It had the infamous "Time without a signal" bug that used like half the battery life per charge. It basically had to be ROMed to work right. And that bug was there for over a year.
It's just sad the phone makers are being so sloppy. It makes Android seem like a POS, when it's really their fault.
Sent from my SPH-D710 using xda premium

Is it normal to lose 27% charge with jjust 40 minutes of screen on time? Phone has been off the charger for maybe 2 hours. Im not getting anywhere near the claims of some people...
Sent from my SPH-D710 using XDA App

Thanks guys for this thread, My first day I went out and had the phone and installed everything and got root and did titanium backup from my EVO 3D, and played some third blade, and got great battery life, but then yesturday went to work and it just tanked 5 hours and down 50% i was shocked, going to pull the battery if that happens to correct that.

This really disappoints me to see the 'Android OS' bug hasn't been fixed by Samsung despite the issue being reported this Spring when the international SGS2 launched. If I remember correctly it's due to the phone not going into 'deep sleep' after it's been unplugged from the charger. Android OS will be listed in the battery stats as the top consumer of battery.. the workaround is to reboot the phone after pulling it off of the charger in the morning.
I hope Samsung stays true to its word and provides steady firmware updates for their recent devices.. NOT to introduce new features but to fix some of these glaring issues (this one first and foremost)

ker0zene said:
Android OS will be listed in the battery stats as the top consumer of battery.. the workaround is to reboot the phone after pulling it off of the charger in the morning.
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I'll have to try that. I know rebooting after the system goes nuts stops the drain, but I didn't realize it wasn't sleeping after being charged. I'll report back.

I experience weird battery draining periods throughout the day as well. I think I'll just try to clear my battery stats later.

[Q] Leaving the phone plugged in for hours at a time?

Quick question, guys.
Will leaving the One X plugged in all night ruin the life of the battery? First thing I do when I get home is plug the thing in (it usually is at <20% charge), and then only take it out in the morning (8, maybe 10 hours after). I am especially concerned as the phone's battery is built in, and replacing it will be a pain.
Thanks for taking time to leave your thoughts.

Oops. Posted this in the general. Moving the thread to Q&A. Apologies for the mix up.

Charger turn off automatically once it is fullly charged
but I will prefer not to leave it on the whole night

Nexus 7 - "Charges" and turns on, but doesn't really charge

Hey everybody, how's it going?
Basically today I was using my Nexus 7 (it has KitKat installed) and it randomly turned off on me. It had a decent amount of battery life too. My heart dropped to my butt since I thought that it was gone for good, I bought it about a month ago and the store (Sam's Club) guarantee expired after two weeks. I did some investigating and all I found was results for when it doesn't turn on and doesn't charge, or if it just doesn't charge or turn on, last two options separately.
My tablet can turn on and it "supposedly" charges, but when I plug in the charger it stays in zero percent even though the charging symbol is there. If I unplug it, the battery symbol tuns red as if it's low on battery. I would see if the battery icon is just 'stuck' and it really is charging, but I don't want to risk letting it die and then not being able to turn it on completely. I tried factory resetting, used another USB cable, I even used another charger (Samsung Galaxy Y). I still got nothing.
Any suggestions?
Edit:
I decided to risk it and use it without the charger. It's working and I'm downloading things from Google Play, even with the battery on 0%. This is really weird....
2nd Edit:
I downloaded a battery life notifier from Google Play, it also says that my battery is on 0%.

Try running a battery calibrator from the play store.
prshosting.org

prsterero said:
Try running a battery calibrator from the play store.
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I decided to take a nap after posting this, now the battery life says that it's charged and I don't even have it plugged. This thing is freaky...
I checked out a battery calibration tool and it needs root. Not sure if I'd like to do that. I rooted my Galaxy Y once and went through a scare, and the process is much easier than on the Nexus 7 from what I've read. Or is there a simple update.zip thingy like for the Galaxy Y?

[Q] Confusion regarding the battery cycles

I recently bought a note 3 and I wanted to ask is it okay if I put it into overnight charge even if the battery is 60-70% ?
Does putting it on a charger over long period of times affect the battery life?

battery has protective circuit that will cut off the current when fully charged, since Li-ion batts are very sensitive to overcharging and discharging bellow spec and will get damaged quickly if done so. However, since there is always some possibility of malfunction I would not leave the batt. at home on the charger and left for 2 weeks vacation, but overnight should be fine, probably many people do so.

pete4k said:
battery has protective circuit that will cut off the current when fully charged, since Li-ion batts are very sensitive to overcharging and discharging bellow spec and will get damaged quickly if done so. However, since there is always some possibility of malfunction I would not leave the batt. at home on the charger and left for 2 weeks vacation, but overnight should be fine, probably many people do so.
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Thank you Pete for such an elaborate reply. In your opinion would it affect the battery if I put the phone over night every night for, let's say, 3-4 months?

I charge nightly so that when I wake up the phone is fully charged. Seriously, if the battery starts to wear out you can simply replace it. It is removable. Not a big deal.

I leave it charging every night
Sent from my SM-N900T using xda app-developers app

Buy an extra battery and swap out when it gets down to 15%. Saves wear and tear on the charging port and keeps away extraneous heat from having the phone itself charging the battery.

muz_grt said:
I recently bought a note 3 and I wanted to ask is it okay if I put it into overnight charge even if the battery is 60-70% ?
Does putting it on a charger over long period of times affect the battery life?
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Imho even if you would charge overnight you wont notice any difference untill your phone is EOL. Even if you would treat your liion battery like a princess it would still die in ~5 years (please correct me if im wrong).
Even though this is only my personal experience and your mileage may differ, but im currently using a HTC HD2 which is still going strong on its first battery. I plug it in almost every night before i go to bed.
Edit: and I must add that really your phone is designed to be used like this. If you only have 70% left and you really need that extra juice the next (few) day(s) because you wont have a charger with you, just plug it in as you go to bed.
If you really go out of your way to rape your battery every day, just buy a new one when its EOL, if you haven't gotten a new device already.
Sent from my Nexus 7 using xda app-developers app