yashsingh1/xdaforums huggingface dataset:
[Galaxy S II General] simonk83:
How long was the screen on for during that time? Try turning brightness down to 0 (I've done that, still looks fine, unless you're outside).

(I wish those signatures were disabled by default in the XDA app :()
[Galaxy S II General] m.stark:
Had my device for 5 days. No idea how many charge cycles, about one to two a day.

I've consistently gotten between 5.5-6 hours of use out of the device on each charge. Before you're alarmed by this, let me tell you I was constantly using the device during this time (it's my first smartphone, I'm still feeling blissful and can't keep my hands off it).

With constantly I mean that I had tTorrent running with 1-2 downloads on either wi-fi of 3G (got unlimited data, no fair use policy), Skype on, TweetDeck updating every 15 minutes and either playing Angry Birds, surfing, listening to music on Spotify, or watching a movie.

My display is usually set between 0-25% brightness and usually ended up being 80-90% of battery usage.

Last night I let the device kill itself peacefully and charged it to 100% this morning.

Currently at 34%, with 10.5 hours of what I consider "light" use. Display has been on for about 2 hours, I've been installing/uninstalling many apps, light surfing, downloading 1 movie, constantly activating the device to check on battery status and tweaking various settings. GPS off. The jump in battery % occurred after I turned the device off, took the battery out, waited 20 seconds, inserted it again and restarted the device, can anyone explain why?

Makes it look like I'll get about 15 hours of estimated life (with 3 hours of display on), with heavily inconsistent use and waking the device every few minutes to check on TweetDeck/whatsapp.

Battery Usage:

Display 35%

Android OS 34% (anyone knows why this is so high? it seems to be using CPU even while the phone is idle)

Maps 12% (why is maps using so much when I never even touch it?)

After some tweaks the battery drain while the phone was idling dropped quite a bit (mainly turning off all contact sync, but leaving gmail sync on and disabling facebook & twitter sync, since I'm using TweetDeck).

Sorry for the messy post, wanted to try to report with as much detail as possible.

I will let the device kill itself again before I charge it and, if anyone is interested, I'll give another detailed report on my next usage cycle.

My device is not rooted, I think I want to wait until there's one that's not got "insecure" in it's name before I try that.

Overall I am very satisfied with the battery life, but I'm not seeing my device lasting 24 hours even with light use, like some people claim theirs do.

If anyone wants me to perform any sort of battery life tests feel free to tell me and I'll see if I can do it.
[Galaxy S II General] simonk83:
Here you go: http://xdaforums.com/showthread.php?p=13608358
[Galaxy S II General] m.stark:
Ah, thanks a lot! Hoping they'll issue a fix within a few days then, once they do I can't help but feel battery life of this device has ridiculous potential :D
[Galaxy S II General] simonk83:
I hope so too, but I very much doubt it. Looking at the Google Code opened issues, it seems to have been going on since last year :( I'm hoping 2.3.4 fixes it, but others have reported it hasn't, so probably not :D
[Galaxy S II General] NIK516:
dam this sucks
[Galaxy S II General] Beards:
As I mentioned previously, I have been doing the 10 charge and empty routines which I always do on my new phones.

Here's the table taken from this morning:-
[Galaxy S II General] DocRambone:
I have the same android os issue, only solution that gives some fix: disable background data.

Its a serious android issue with gingerbread.
[Galaxy S II General] Beards:
It can be a little extreme but... turn it off if you don't want auto notifications.

However, you may use more power in having to keep re-establishing the connection.

Really, it depends on how often a connection is needed. Manual sync every hour would warrant leaving internet always on, but every 6 hours it can probably be left off.

I find the major battery killer is being in an area with a very weak 3G signal. It causes the phone to switch between 2G & 3G constantly so the phone has to work harder and use more battery to maintain good reception (True of all phones).

The Answer? - Switch to 2g (GSM Only) when you are in that situation.

LaptopMag blogged a small print on Background Data here.
[Galaxy S II General] StickyGeko:
my os is 13% screen 38% - what app doe you guys use to check the battery/temp ?
[Galaxy S II General] DocRambone:
Its not a weak signal issue, the "android os" is a bug in ginger, affect many handsets. Maybe a security issue?, seems the com.android.providers.security process is active all the time
[Galaxy S II General] Beards:
I use Battery Status Bar.

Mine is configured to show in the Notification window:-

Level

Health

Volts

Temp

Plugged In At
[Galaxy S II General] Beards:
Doc, that may be true but I said "I find". :)
[Galaxy S II General] NIK516:
76% android os usage, absolutely tragic.
[Galaxy S II General] jonrwg:
WOW.. that is way too high :eek:
[Galaxy S II General] Leggenda:
Android OS Usage is the addition between some application used...

In my cases, in this moment Android OS Usage is to 24% (in the details, about 34 minutes)... In fact this morning I used 9 min 48 s of Music, 9 min 12 s of Internet, bug of the Wi-Fi sharing ( 8 min 39 s) and Android System is on 5 min 0 s...

The addition of this use is, in fact, about 34 minutes... ABOUT!

Ps. all the times that i wrote in black are the "Total CPU" utilization in the details of those application.
[Galaxy S II General] vimto25:
yeah i dont think its much to worry about tbh
[Galaxy S II General] Leggenda:
I don't understand... :D
[Galaxy S II General] elpapo:
That was a poor battery history. :(
[Galaxy S II General] Beards:
What exactly are you calling poor here?

The screen capture showed 1d 10h 31m 23s on battery and still 20% left.
[Galaxy S II General] JexL:
Should get in the habit of mentioning our screen display times as well not just how long battery lasts.i personally get around 3 hours of screen time each charge.
[Galaxy S II General] StickyGeko:
A better day fire me... I did cheat a little with a small charge this morning b4 wrkn....screen time 4hr
[Galaxy S II General] dk206:
I always get 7% Android os and 4% Android system

Swyped from my GT-I9100 using XDA App
[Galaxy S II General] dan13l:
Oddly enough, after stellar battery life yesterday, today has been pretty sucky.

25% left, 11h 34m on battery.

25% display (2h 21m).

25% android os (CPU total 1h 19m).

22% voice calls (53 minutes).

10% Android system.

5% wifi sharing.

Wifi sharing has never been turned on, so that's an odd one. Also 25% android os seems a bit high compared to yesterday (when I was using the camera a lot and almost managed 24 hours battery).

Methinks there are one or two teething problems with the current firmware that will hopefully get resolved (either by Samsung, or those clever rom developer dudes).
[Galaxy S II General] RyanZA:
The wifi sharing bug seems to affect battery life fairly badly. If you see wifi sharing in the list, your battery life is going to be pretty bad. I think it has something to do with Kies wifi sync.

It's very likely a bug in the firmware, nobody knows why/how yet afaik.
[Galaxy S II General] DiamondGar:
I think there is potential for epic battery life with this device if there is some serious rom development. Im hoping for a solid CM7 implementation, but a MCR rom by paul would be a good start i think as im sure he will find some things to optimise.

A custom kernel with setcpu could also be really benificial hopefully.

Hopefully some of the issues may be fixed by an update to 2.3.4 in near future too.
[Galaxy S II General] dan13l:
I've never done anything with Kies, so we can probably rule that out. I was just reading the wifi sharing problem thread actually. Definitely some sort of bug.
[Galaxy S II General] rockky:
I think this has broken the S2 deal for me. Same with me. I'm a heavy poweruser. Use charged like a lap top in afternoon ....need it fully charged after that.

I've used 3 different chargers....same thing...it actually loses charge.

No No Sumsung...not GOING to 'terminate apps so it charges correctly'. That's why I bought a dual core big processing device. Fairly incredulous.
[Galaxy S II General] rwc3b:
Dumb question but how do I turn off the "awake" state?
[Galaxy S II General] RogerPodacter:
that my friend is a bug in 2.3.3. many models are seeing that issue. when screen goes off that SHOULD show as not awake, but because of this bug it doesnt always happen and instead you end up with the device showing as awake for long periods of time. my nexus one has the same bug:(
[Galaxy S II General] RogerPodacter:
for what it's worth, we did some really serious enhancements to the nexus one battery driver and got the improvements into the cyan repo source. now that samsung released the source code for the SGS2, i browsed the code and it seems like there may be some cool changes that could be done. check my signature link for the project we did on the n1.

one thing i noticed is that the SGS2 charge current seems to be dictated by code, and set to 650mA. normally this is left to be whatever the battery will allow. but this driver seems to hard code it at 650mA, not sure why, but that is low enough where you could pull more power than 650mA even while plugged into AC outlet, pulling more juice than the charger can supply.

cant wait to get this device, make some code fiddles and see what happens. hope i wont blow my face off.
[Galaxy S II General] rwc3b:
Thanks. I had no idea. I guess nothing I could do but wait til the next update, eh? Wonderful.
[Galaxy S II General] dk206:
It would be really really helpful if you would tell us what firmware you guys are on. The ones who claim they have shoddy battery life.
[Galaxy S II General] NIK516:
This a screen shot of my version

http://imageshack.us/photo/my-images/806/sc20110510100520.jpg/
[Galaxy S II General] intruda119:
It just took me an hour to kill the battery from 1%. After watching YouTube for 40mins, browsing the web and playing some games it finally died. I'm having great battery life with my sgs2.

Started the day around 50% and after extreme heavy use it finally died(7am-9:30pm). Anyone having problems need to check the apps there running.

After not having any problems either users devices are defective or user error.
[Galaxy S II General] NIK516:
Thats great that your having good battery life and rubbing it in our faces, maybe when you have a problem ill reply by telling you : Nothing wrong with my phone so i guess you should learn to use yours properly.

And if you read though the post you would notice that this is in part a OS issue, not a setup issue.

But thanks for the helpful worlds, ill be sure to give you a thanks.
[Galaxy S II General] cmd512:
Battery life here has been pretty impressive compared to the SGS. Granted, this is after:

1) Rooting + removing a sh*t-ton of Samsung/other bloatware.

2) I have 4 (2 push/2 pull) Email accounts (hotmail, yahoo, gmail, and work Lotus Notes Traveler) checking at 1 hour intervals. Keep in mind, any E-mail set to push real time will SUCK up your battery... setting it to push at hourly intervals makes a huge difference.

Just ran into this bug tonight after going into the study after dinner only to find the SGSII's screen bright and lit up. That's when I realized the screen/system would not go to sleep if screen timeout is set to anything at 1 minute or higher. Screen/system would timeout normally with any setting under 1 minute. That meant it was bug huntin' time.

At a 1 minute timeout setting, the screen would dim as if it was ready to go to sleep... but the second the minute hand on the clock moved, screen lit up again. So, my first hunch was to check all 3rd party apps that had some sort of clock counter. Sure enough, if I shut off the service to my alarm clock (I use Alarm Klock from the market, free app and works flawlessly on my SGS Froyo 2.2.1), the screen would timeout normally with any timeout setting (15s ~ 10 minutes). The second Alarm Klock was enabled, screen would stay lit with a screen timeout setting of 1 minute or higher.

So, I believe Google did something VERY different with Gingerbread's handling of idle state timer calls. As I proved tonight with Alarm Klock, there are apps that function perfectly under 2.2.1, but with Gingerbread, will constantly reset the idle state timer and keep your phone from going to sleep. So, keep an eye out for those!
[Galaxy S II General] JJEgan:
Must admit my initial battery life was excellent then after flashing three times and rooting it falling off a cliff .

But judged by SGS 1 that is to be expected .

jje
[Galaxy S II General] Bajaj_86:
Hi,

I'm a newbie in this Android World. I just got my SGSII yesterday and last night is my first charge of the phone.

Charged while playing it.

I unpluged the phone from my laptop charger at 7AM, and by lunch time the battrey had drained to 10%. Is this normal??

I used the phone mainly for:

~ Gmail (Push immediately)

~ Gtalk

~ Play around with the phone (i.e. Installing apps)

Do you think this is normal??

Thanks Guys for your help
[Galaxy S II General] SuperTheMando:
Hey um... I was wondering if I could get a tl;dr?

This thread is very very long, and I'd like to keep up with it, but if someone could catch me up on what's happened so far I'd be forever grateful!

Just ordered my SGSII of Handtec. :)
[Galaxy S II General] hazem77:
My battery does not last half a day!!! i only have wetaher widget on and using Juice ultimate!!
[Galaxy S II General] skibax84:
force to keep the 3G connection

I noticed that - the phone is trying to force to keep the 3G connection, when the coverage is very weak, ( the GSM mode would give 100%), I expect that it may have an impact on battery life. Has anyone noticed something similar and what do you think about this?
[Galaxy S II General] Beards:
The first couple of charges is never going to represent the real battery performance and as such should be dismissed.

However, I don't recommend using the phone for long periods whilst charging as it places too much strain on the battery (it is the same for all batteries i.e. Laptops).

The best method if time allows is for the first several charges run the battery completely down until the phone switches off and then fully charge.

This will then bed the battery in and you should start to see a good battery performance as time goes by.

Once the battery is bedded in I normally top the battery up at around 60% to 70%, then once a month I run the battery completely back down to 0% to keep the battery in tip-top condition.
[Galaxy S II General] bilboa1:
7AM to 12 thats 5 hours.

Sync + play around with the phone and 10% in 5hours (2% per hour) i'd say thats pretty good lol.
[Galaxy S II General] kumarshah:
I believe he is saying it drained to 10%, so that's 90% drain in 5 hours.
[Galaxy S II General] bilboa1:
then its pretty bad

:D
[Galaxy S II General] Bajaj_86:
I think I'll take all the advice and report back after I got 10 Charged on the battery. However, I normally charged the battery at 5% - 7%...

Thanks for the input guys, really appreciated.
[Galaxy S II General] dk206:
Read again. 10% in 5 hours. Meaning battery depleted only 2% every hour. Now he is sitting at 90%

Swyped from my GT-I9100 using XDA App
[Galaxy S II General] David Horn:
You guys do realise that by completely discharging the device multiple times you are irreparably damaging the battery? It's not surprising that your battery life is now shocking if you drained the battery to empty 10 times in a row.

I doubt that you'll teach the phone anything about the battery characteristics either; it's exceptionally unlikely that it predicts the remaining battery life based solely on voltage between full and empty.

Your only hope is that the battery controller (inside the battery) will cut off power to the device in an attempt to protect itself from further damage. But it wouldn't surprise me if you have significantly shortened the life of your battery, and now receive very peculiar indications of battery level.

This is not to deny the importance of making sure the phone receives a full charge on first use - THIS is what is used to calibrate most modern batteries.
[Galaxy S II General] Mittaa:
I do not think its a good idea to run battery completely down ...

And you sure your recommendation are correct?

Simple Guidelines for Charging Lithium-based Batteries (from batteryuniversity.com)

- A portable device should be turned off while charging. This allows the battery to reach the threshold voltage unhindered and reflects the correct saturation current responsible to terminate the charge. A parasitic load confuses the charger.

- Charge at a moderate temperature. Do not charge below freezing.

- Lithium-ion does not need to be fully charged; a partial charge is better.

- Chargers use different methods for “ready” indication. The light signal may not always indicate a full charge.

- Discontinue using charger and/or battery if the battery gets excessively warm.

- Before prolonged storage, apply some charge to bring the pack to about half charge.

- Over-discharged batteries can be “boosted” to life again. Discard pack if the voltage does not rise to a normal level within a minute while on boost.

http://batteryuniversity.com/learn/article/charging_lithium_ion_batteries

http://batteryuniversity.com/learn/article/how_to_prolong_lithium_based_batteries
[Galaxy S II General] bilboa1:
actually you should go to "empty" then full again a couple of times to calibrate.

it doesnt calibrate "the battery", that term is over used. it calibrate the data about the battery. That's different.

The batteries will be more healthy if they are not kept at low voltage (aka empty or nearly empty).

Please note that i wrote "empty" with quotes. By this first "empty" I mean until the battery gets <10%. You can let it auto shutdown the phone too, but dont try to go further with the drain. The auto shutdown happens to avoid going to low in voltage and damaging the battery, in fact. Still I wouldn't do that too often. Neither good for the battery's health, neither necessary.

This is also a common misconception, due to the old nicad-type batteries that would last longer when discharged completely. li-po li-on etc batteries are different and if they got under their minimum cell voltage they just die or/and will discharge a lot quicker in the future (aka you damaged it).

In general, after the calibration procedure is done, just use your phone normally and charge it whenever you feel like it. As long as its not 24/7 in charge or going empty all the time you'll be just fine.
[Galaxy S II General] Beards:
Have a read of this.

Although it talkes of Notebook Batteries the principle is still the same.

They are Lion.
[Galaxy S II General] dk206:
I agree with above. You're NOT meant to totally and completely deplete your lithium battery to zero all the time. You should do this once for battery caliberation. No more. And should try to keep it above 10% until you get home and charge. Its not good for battery life and battery life span

Swyped from my GT-I9100 using XDA App
[Galaxy S II General] Sticks02:
I don't think some people here have taken a course at Battery University...:(

Just discharge it ONCE when you get it, fresh from the box. Then use it as normal, recharge whenever, etc. No need to let it die at 0% every few days for 'calibration'...
[Galaxy S II General] JexL:
Got 3.5 hours of screen time once again. used over a 11 hour span
[Galaxy S II General] jonrwg:
Why on earth wifi sharing running in background?
[Galaxy S II General] bilboa1:
On Mars it works just fine.
[Galaxy S II General] jonrwg:
LOL.. But it taking up my CPU about 35%. :cool:
[Galaxy S II General] dz@:
As I am an old school believer I has been "irreparably damaging the battery" of my HTC Touch HD for more than 2 years :) Mostly I charge it once it has run out of battery completely and switched off.

So far I have same stable usage time as in early days.
[Galaxy S II General] aonanodad:
NOT a good idea to run a lithium battery down completely with the hope of "calibrating" the charge/discharge circuitry or software. It will shorten the life of your battery for no benefit at all - the cycling will not calibrate anything.

WHAT IS a good idea is to charge the battery as often as possible. LI-Ion batteries will last much longer if kept topped up. If you have spare chargers at home, in the office, or in your car, it is good to plug the phone in whenever possible.

However, LI-Ion batteries have a "shelf-life" whether they are used or not. Samsung batteries are among the best available (assuming Samsung is not buying these batteries from some cheaper Chinese source), but still the batteries will probably not last more than 3-5 years no matter how well they are cared for or how much or how little they are used. Not sure any SGS2 early adopters will be using their phones that long anyway.

Replacement batteries are not too expensive, so the convenience of charging infrequently might be worth the price of new batteries.
[Galaxy S II General] sasifilb:
I read a lot here and still cant get a descent answer.

How long the battery last? no rooting, no hacking, no major changes, not a nerd and considering to buy this. All the impression i get from this forum is people trying to manipulate their phone to survive.

Can it really survive to last a day or more without any changes. i m a normal user, social media, you tube, maybe some live TV streaming for 10 minutes or 30 minutes a day. and lots f whatsapp texting.

What matters really to me, i own an old Nokia n95, how will the change in battery be to me. do i have to hold a charger when i walk to work or home, or a battery of a Samsung can last 24 hours with a normal not so smart user?

P.s your reply matters, becoz i m so scared from all these posts that i might consider an IPHONE lol not sure, how much that battery last.

Also, does anybody know if there is any video calling working on this thing, i skype a lot and that s the reason i might consider the suiciding Chinese company. else if somebody can suggest something similar to Skype and stable on SGS2

thank you :)
[Galaxy S II General] windowlicker:
You need to ask yourself first of all: is battery life the most important thing to you? If yes, then I don't think you should buy a big smartphone with millions of features and a huge touchscreen, because no such device will have incredibly awesome battery life. You will have to charge the device every day, especially if you have Facebook/Twitter clients polling the web for updates every 5 minutes, live TV streaming, IM services and chatting. These features will tear through the battery.

The iPhone isn't any better. The iPhone lasts a long time on standby as long as you close down apps in the "multitasking" list and disable push services and such. Facebook for example is a huge battery drain on the iPhone, just like it is on Android.

EDIT: Sorry, I don't actually own the S2 yet, but just thought I'd chime in anyway... :)
[Galaxy S II General] cmd512:
Good question, I certainly don't have mobile AP running or anything. No reason why that service should be running.
[Galaxy S II General] leventbb:
iphone 4 is not better than SGS2, i own sgs2 and my wife has i4. we both charge almost once every 24 hours.

I have not touched (ie root, flash etc) my SGS2 since the purchase and not feeling unhappy because of the battery.

There are some no-brainers such as keeping wifi off when you do not need it and stay on GSM in a poor coverage area..

Whatsapp and facebook are huge drains on the battery, without those two I think my battery would easily pass 24 hour barrier.
[Galaxy S II General] jonrwg:
Same. Out of sudden my watchdog alert me that wifi sharing is using up more than 30%. And I was at a mall that time without wifi around? :confused:

But it stay constantly at 3% even-though I frozen it and it still running in background. :eek: Die hard service.. LOL