Develop Bugs

[Q] Phone uses 2% battery every 15 minutes

My phone seems to be using 2% battery every 15 minutes on standby, worse when its on.
When I check what is running, it says Android OS 50%...... what can I do? I usually charge my phone three times a day.
Sent from my Galaxy Nexus using xda premium

I use a variety of apps to check what is going on with my phone.
Watchdog - monitors apps for excessive cpu usage
Cpu spy - see how long your phone stays at each frequency, but more importantly in deep sleep.
Battery monitor widget - monitors battery usage
System tuner pro - get detailed analysis of a recorded system usage.
Also, when in battery usage, I click android os to see how long it has kept your phone awake. Have you made any changes to your phone? Installed a custom ROM?
Sent from my Galaxy Nexus using xda premium

Also...give it a few days of charge-ups. It really does make a difference.
FWIW, with moderate use, my Droid Charge 4G does about 10-15% every hour. So I don't even think 8%/hr is that bad... :/

no changes to the phone, its all stock. Any benefits moving to a custom ROM on the nexus?
I've had the phone for two weeks, battery has deteriorated. Now charge it three times a day.
Sent from my Galaxy Nexus using xda premium

Crazy CS said:
no changes to the phone, its all stock. Any benefits moving to a custom ROM on the nexus?
I've had the phone for two weeks, battery has deteriorated. Now charge it three times a day.
Sent from my Galaxy Nexus using xda premium
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You probably never calibrated it properly to begin with. Charge to 100% > unplug > wipe batterystats.bin > let the battery drain completely until the phone powers off. Then charge it continuously over night and in the morning unplug and let the phone drain completely until it powers off.
I am a pretty heavy user as I text literally every 2 minutes all day (girlfriend ) and I manage to get 20-25 hours easily.
I also drain my battery out completely every day for good measure
Charging in between screws up your calibration, try not to charge unless you are below 15%. And do not disconnect it until it is fully charged (98-100%).
Note: I've also noticed wifi saves you a lot more battery juice than being on 3G/4G, so keep your wifi active if you are in range

KiNG OMaR said:
I also drain my battery out completely every day for good measure
Charging in between screws up your calibration, try not to charge unless you are below 15%. And do not disconnect it until it is fully charged (98-100%).
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This is just not accurate for Lithium Ion batteries, which have no cell memory and gain more from frequent shallow charges than deep charges.

krohnjw said:
This is just not accurate for Lithium Ion batteries, which have no cell memory and gain more from frequent shallow charges than deep charges.
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Not to mention draining a Li-ion past 5% can shorten the life of the battery.
Further Li-ion's have a lifespan measured in cycles. You get about 500 cycles on a typical Li-ion. A cycle is a drain and charge. If you use 50% of the charge and then recharge to 100% you only use half a cycle. By needlessly draining the battery you are using up limited cycles reducing the life span of the battery.
While I'm sure android's calibration needs to know the upper and lower boundaries of a charge I'm certain it would be smart enough to handle charges when the battery isn't completely drained. Most battery calibrations work this way. Every once in a while you need to charge to 100% drain to 5% and recharge without using to 100%

Wheres battery stats.bin located?
Sent from my Galaxy Nexus using xda premium

Crazy CS said:
Wheres battery stats.bin located?
Sent from my Galaxy Nexus using xda premium
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Clockwork Recovery -> Advanced.
.. file is in /data/system i believe

its probably a bad app working with ICS.
Use watchdog and it will tell you.
Check your widgets that they aren't constantly refreshing.

Battery drops 6% when unplugged.

I currently run MIUI on my Evo, and I'm having a problem. My phone will say its fully charged and all, with the green LED saying so, but when I unplug the phone, my battery level drops down to 94% immediatly. What is this? I bought a brand new battery and I still got this problem. Anyone who can I can do?
Sent from my HTC EVO 4G using XDA

You either need to calibrate your battery (app off the market). Or try using a SBC kernel, which properly charges your battery to its full capacity. Make sure its an aosp kernel like mason, or taimat.

Lol sane experience on morning
wanam v10.6 siyah v3.0.1

Definitely needs calibration.Just search for how to properly do it on the forums.I personally use battery calibration from the app store.Charge the battery to 100%,then use the app.Unplug through phone and use the phone all the way until it dies on its on.Then plug it in without turning it on and wait until its fully charged.Turn on and use it once more until it dies.Charge again to 100% then after that you should be good to go.Hope this helps ya.
Sent from my SAMSUNG-SGH-I717 using XDA Premium App

A non-sbc kernel will charge to 100%, then begin to discharge to about 90%, then cycle back up... Depending when you pull the plug, in reality it could be anywhere inbetween that range, so 100 is not a true 100... Calibrating the battery by deleting the bin file doesn't produce any long term results..
A manual way to mimic a full charge would be to charge to 100 percent, unplug, plug back in for a bit and repeat about 10 times, and it should give you a decent charge.
That's a manual way of doing what a SBC kernel does automatically for you

Hey,
Like they said get the SBC, and calibrate your battery, and that should fix it.
I assume at night you are plugging it in till the morning, and this is your issue because in the middle of your sleep it is reaching full and stopping its charge. so by the time you unplug it drops down to how much it discharged.
Charging with your phone off solves this to

Let your phone completely drain till it turns off. Charge the phone while its off till you see the green "charged" light. Unplug usb, wait for green light to disappear and plug usb back in, phone will still charge. Repeat process about ten times. On the tenth time boot into recovery and wipe batt stats, then reboot phone.
Sent from my PC36100 using XDA

Flashed the SBC, and properly calibrated my battery. I'm still at 100% battery level after an hour!
Sent from my HTC EVO 4G using XDA

Good to see that worked for ya. I'd +1 the SBC kernel if you hadn't found that it has been working for you. I've been using Mason's 14 with ICS for a few weeks now and i've found that with the screen off, the battery sits at 100% for quite a while. I haven't used the battery calibrator and maybe i should see how that helps. Does it show significant results or is it mostly a gimmick?

dougfalk said:
Good to see that worked for ya. I'd +1 the SBC kernel if you hadn't found that it has been working for you. I've been using Mason's 14 with ICS for a few weeks now and i've found that with the screen off, the battery sits at 100% for quite a while. I haven't used the battery calibrator and maybe i should see how that helps. Does it show significant results or is it mostly a gimmick?
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Im not sure what everyone on here thinks it does, but calibrating the battery is strictly for stats. It will not lengthen the battery life or keep it from draining down from 100% faster. All it will do is assure that your battery stats, aka estimated time you have left on your battery, are more accurate.
---------- Post added at 05:25 PM ---------- Previous post was at 05:15 PM ----------
msr4 said:
Flashed the SBC, and properly calibrated my battery. I'm still at 100% battery level after an hour!
Sent from my HTC EVO 4G using XDA
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good luck. I tried sbc and it was working well for about two weeks, then my battery suddenly started draining super fast. Rumor has it that SBC will in time ruin your battery, which it seemed to possibly be doing to mine. Got rid of SBC, flashed back to build28, ran vipermod script and undervolted -75mV and im magically back to normal.
My findings are that if I just run the stock kernel with build 28, I get the best battery life. As soon as I started trying mason kernel, tiamat kernel, or even faux kernel on build 31, my battery drained too fast for my liking. Thus far I have reached 40 hours on my battery on build 28, with vipermod, stock kernel!

I just got brand new batteries, i have not calibrated nor wiped battery stats after flashing. I do have Mason's kernel and am under-volted by -50. I also have an app called battery xl it helps control what is running when you may not be aware or forget. My battery stays at 100% for over 2hours with minimal use. The only thing i heard is that you have to use the battery down to 10% and then charge while phone is off.Do this about 4 to 5 times and that conditions it(when it's brand new) and it will help your battery last longer before needing a replacement.
Just my .02

Several people have reported bad experiences with the SBC kernels, but there are many more (myself included) that have had absolutely no issues with them and I have used several iterations of the SBC since it was first released for the Evo.
At this point, for me, the benefits more than outweigh the risks. If you do have a problem, buy a new battery. They are pretty darn cheap these days.

Fully Charged Phone - Shouldn't it be 97%?

I noticed my GN charges until 100% or "fully charged" (battery widget that spells it out). Shouldn't it be 97% or 98% max when charging to prevent damaging and preserve longevity of the battery? Or is this some new thing with 4.04 that it'll tell you 100% when it's really 97%? I do notice it drops down to 99% really quickly.
I'm stock on 4.04 and I'm using the provided USB cable and charger plug.
Thanks.

I take it you came from a Nexus S before? I was surprised too but I believe it cuts off the charging to prevent overdose of electricity. No worries on it mate.

It will charge to 100% of what ever value you set or as default comes.. Like you can see on the screenshot
Galaxy Nexus AOKP m5 Franco kernel m3

^^this^^

msedek said:
It will charge to 100% of what ever value you set or as default comes.. Like you can see on the screenshot
Galaxy Nexus AOKP m5 Franco kernel m3
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Not everyone uses that.
The way the battery works is it charges to full, then takes itself off the charger until it goes down to say 95% and then at that point it goes back on the charger until it's at 100% again, so on and so forth.

Using custom ROM?
Maybe you need to calibrate the battery after you flash new ROM

vdnuouo said:
Using custom ROM?
Maybe you need to calibrate the battery after you flash new ROM
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Wiping batstats does nothing.

so basically it is safe to just leave it plugged in all the time then, the phone by default is DEFINITELY stopping charge at 100%, Correct?
because i know 2 facts about lithium batteries which i learnt today....never leave it permanently charging. and never let it drain fully all the time (the 40-80% charge rule).
im just worried that if i leave it plugged in it'll continue charging even when its at 100...
Do you know if - with that different kernel/ROM - whether you can set it so that you can leave it plugged in - and it won't charge past say....96%. And when it reaches that limit, it lets the battery drain back to say 40%. Before charging again - any software that will let you do this?

schueyisking said:
so basically it is safe to just leave it plugged in all the time then, the phone by default is DEFINITELY stopping charge at 100%, Correct?
because i know 2 facts about lithium batteries which i learnt today....never leave it permanently charging. and never let it drain fully all the time (the 40-80% charge rule).
im just worried that if i leave it plugged in it'll continue charging even when its at 100...
Do you know if - with that different kernel/ROM - whether you can set it so that you can leave it plugged in - and it won't charge past say....96%. And when it reaches that limit, it lets the battery drain back to say 40%. Before charging again - any software that will let you do this?
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Is how phone even on the charger that long..? Something like over night won't kill your battery. The software is supposed to tell the battery when to take itself off of the charger and when to go back. You can use a kernel that will let your battery ONLY charge to a certain percentage.
Sent from my HTC One X using xda premium

You do know todays chargers have technology in them to prevent this right? They have for a while, overcharging is mostly a thing of the past, unless you buy cheap, flea market chargers.

in Recovery Mode there is an option called "battery ststus calibration" (something like this which I cant remember) . actually any percentage of battery use can be "calibrated" into 100%, the number is not important.

Okay, as long as charging up to 100% isn't damaging my batteries.
I did come from a Nexus S, and I always thought that when it stopped charging at 97% that was a good thing to prevent damage to the battery. So naturally, when I see it's going to 100% every night, I imagine it's damaging my battery.
Thanks all.

qwsdert4 said:
in Recovery Mode there is an option called "battery ststus calibration" (something like this which I cant remember) . actually any percentage of battery use can be "calibrated" into 100%, the number is not important.
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You cannot calibrate your battery. You can condition batteries. Wiping battery stats and so called calibrations apps do absolutely nothing.
Sent From My Sprint Galaxy Nexus via XDA Premium

onthecouchagain said:
Okay, as long as charging up to 100% isn't damaging my batteries.
I did come from a Nexus S, and I always thought that when it stopped charging at 97% that was a good thing to prevent damage to the battery. So naturally, when I see it's going to 100% every night, I imagine it's damaging my battery.
Thanks all.
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I think "Battery Life Xtender" feature in some ROMs caters exactly to ur requirements. see this thread http://forum.xda-developers.com/showthread.php?t=1257497(just for example) and find some ROM in GN android development section

onthecouchagain said:
Okay, as long as charging up to 100% isn't damaging my batteries.
I did come from a Nexus S, and I always thought that when it stopped charging at 97% that was a good thing to prevent damage to the battery. So naturally, when I see it's going to 100% every night, I imagine it's damaging my battery.
Thanks all.
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That's just because that's how the nexus s battery driver was written. The galaxy nexus driver isn't written with the 95% recharge limit. Its OK though there's no danger whatsoever leaving the phone charging overnight.

i mean, the feature is included in some of the GN roms
Sent from my Galaxy Nexus

Yeah I know some devs added it in, but its nor in the stock rom from Google.

[Q] Questions about battery life.

-Does keeping the phone plugged in via USB (when battery is at 100%) decrease battery life?
-Approximately how long should the battery last if the phone idles? If the screen is on 24/7?
-Are these batteries any good compared to the stock one?

IamaznX said:
-Does keeping the phone plugged in via USB (when battery is at 100%) decrease battery life?
-Approximately how long should the battery last if the phone idles? If the screen is on 24/7?
-Are these batteries any good compared to the stock one?
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Click to collapse
1.) Plugging in the phone while charged does decrease the battery life as you can only charge a battery for lets say 1000 cycles or so.
2.) Battery life depends on how long you use your phone, your ROM so I couldn't say. But my phone with the screen on lasts about 8 hours (SGH-T989)
3.) Check the reviews, it has five stars so I would assume that the battery is pretty good.

nivekx9 said:
1.) Plugging in the phone while charged does decrease the battery life as you can only charge a battery for lets say 1000 cycles or so.
2.) Battery life depends on how long you use your phone, your ROM so I couldn't say. But my phone with the screen on lasts about 8 hours (SGH-T989)
3.) Check the reviews, it has five stars so I would assume that the battery is pretty good.
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Is losing about 30% battery life overnight (about 7 hours) with the screen off normal?

IamaznX said:
Is losing about 30% battery life overnight (about 7 hours) with the screen off normal?
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Ehh I wouldn't think so...unless something is waking it up every now and then like a app or something...I normally loose about 10% if that if I let it sit over night
Sent from my SAMSUNG-SGH-T989 using xda premium

IamaznX said:
Is losing about 30% battery life overnight (about 7 hours) with the screen off normal?
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Not at all. I would use a battery monitor app to see what's draining the battery because that's very excessive drainage.
I can't imagine how much it drains when you're actually using it...

what rom/kernel are you using?

I agree with what others here have said, but just to add a little something, I heard that for the best battery "life" its best to try and keep it between 20% to 90%. Don't quote me, I heard it on one of those YouTube tech channels, I wonder if that is true. I always thought that it was best to completely kill the battery and then fully charge it.
Sent from my SAMSUNG-SGH-T989 using xda app-developers app

inocent3 said:
I agree with what others here have said, but just to add a little something, I heard that for the best battery "life" its best to try and keep it between 20% to 90%. Don't quote me, I heard it on one of those YouTube tech channels, I wonder if that is true. I always thought that it was best to completely kill the battery and then fully charge it.
Sent from my SAMSUNG-SGH-T989 using xda app-developers app
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That's for a new battery. Only for a couple full cycles. Else it's best to charge when you hit 15-20 and charge uninterrupted to 100.
Sent from my SGH-T989

App that will let me set max battery charge percentage?

Hey everyone. I am coming from my Nexus S to a new Galaxy S3 on CM10.1, and I was wondering if there was an app for the S3 that would allow me to set the maximum for battery charging. NSTools for the Nexus S allowed me to do this, and I would usually set the max to 97 or 98 percent. The setting under NSTools was called Battery Life Extender, I believe.
Is there anything that can accomplish this same task for the S3? I don't like having my phone charge all the way to 100% every single night.

No there isn't and letting it charge to "100%" isn't going to do it any harm. If you remember all the talks on the NS forum, the battery doesn't really charge to 100% unless you bump charge.

CrackerTeg said:
No there isn't and letting it charge to "100%" isn't going to do it any harm. If you remember all the talks on the NS forum, the battery doesn't really charge to 100% unless you bump charge.
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Ah, okay. So 100% on the battery counter doesn't literally mean that the battery is being charged to its absolute maximum capacity? Does the software still kick in and stop the phone from overdrawing charge once it's full?

Yup. If it did it for our old crespos, it definitely does it for this beast.

above 4.2v is bad
This app you asked about is very important. Charging a battery more than 4.2 volts dramatically shortens its recharge cycle numbers. I measured my battery volts, found that 4.2 volts is achieved around 85%.
An app that would prevent charging over 80% will be great.
Thnks