Are there any good ways to extend battery life besides the obvious stuff (no WiFi, GPS, screen brightness, etc.)? I just converted from my iPhone 4 to a Nexus S and battery life is pretty miserable - I can make it through a day but I have to plug in as soon as I get home. If I could stretch that 12 hours to 18 or so it'd be perfect. My iPhone could do 24-36 no problem, so I feel like 18 should be reasonable.
You can try different kernels for your firmware. The custom ones (good ones) normally consume less battery.
You can try to calibrate your battery, as well.
That is if you're rooted. If you're not there's not that much you can do. Install Current Widget from the market and let it be in standby for around 1 hour with WiFi and that stuff off, and check how many mA it's draining.
Other than that, turn auto sync off, and don't let everything send out push notifications (news readers, Facebook etc.) and if you're using a weather widget check that it's not updating every 30 mins or something.
BazookaAce, but having a smatphone like this without being rooted it's a waste of gadget...IMO.
Yeah, I'm rooted and running brainmaster's MIUI ROM. I do have syncing turned on for everything, I'll try messing with that since I certainly don't need FB or Twitter updates every 30 seconds.
just dont use any of battery saver tools. it doesnt work. wipe battery stat if ur phone rooted.
I have a similar problem. I am running an XT860 and am barely getting 12 hours and that's with an extended battery! I have read that keeping the software on your phone up to date usually improves the battery life.
What kind of droid do you have?
Root your phone, install cyanogen or miui.
Download setcpu app.
In setcpu, set it so your phone uses 500-600 mhz of processor speed when the screen is off.
That alone should help your battery life by at least 25%.
Not so sure setCPU is the end all solution here. I have this as well and I have mine actually down to 245mhz when in screen off mode, yet my battery life still is horrible. I have screen brightness pretty low and only gmail is setup to autosync, and checking the stats gmail does not use much of the battery.
I think it also has a lot to do with how good of a signal you get in your area. If your phone is constantly cycling through to get a signal that will eat up your battery as well and is pretty much out of your control.
Dropping the speed with the battery life sucks hd2 setcpu that does not taste at all
Related
Does the next update (2.1) somehow include a way to improve battery? I'm guessing no, wouldn't you need to replace the battery itself?
There may be battery performance improvements in the next update. My battery life is actually stellar. I set Timescape to update every 3 hrs and have brightness at about 75%. Off the charger at about 7am and at midnight that night I'm usually at around 40%. That's plenty good enough for me.
xperianewbie said:
Does the next update (2.1) somehow include a way to improve battery? I'm guessing no, wouldn't you need to replace the battery itself?
Click to expand...
Click to collapse
I dunno about the update and battery life but, Its 100% to 20% in 25-27 hours for me which i think is awesome as my usage is high.
Try setting the updates of your apps lower, check the Batt usage history from the settings menu to see what sucks the juice more.
If you want more battery life then you'll have to sacrifice some updates, which according to me ruins the entire purpose of having such a high-end smart Android device. Just use the phone the way you like it, have the charger with you always
Whatever phone you choose i think you are going to have this issue since batt usage depends solely upon the way you use your phone. In 2.1 live wallpapers suck more juice so you'll be advised to turn it off its either functionality or performance, the decision is yours
According to me any phone u buy will have same battery life or there is 70% Probability to have worst battery life. X10 has one the best battery life amongst all smartphones
Sent from my X10a using XDA App
sam_a200 said:
I dunno about the update and battery life but, Its 100% to 20% in 25-27 hours for me which i think is awesome as my usage is high.
Try setting the updates of your apps lower, check the Batt usage history from the settings menu to see what sucks the juice more.
If you want more battery life then you'll have to sacrifice some updates, which according to me ruins the entire purpose of having such a high-end smart Android device. Just use the phone the way you like it, have the charger with you always
Whatever phone you choose i think you are going to have this issue since batt usage depends solely upon the way you use your phone. In 2.1 live wallpapers suck more juice so you'll be advised to turn it off its either functionality or performance, the decision is yours
Click to expand...
Click to collapse
Hmm... could it be just me? My battery went from 100% to 53% from just staying locked over night (around 9 hours). I checked what's been eating it and it said "Cell Standby" and "Display". My brightness is on the lowest possible and Wi-Fi and Bluetooth is constantly off. I'll check that Timescape stuff and try to get the App Killer from the Market... (if my device even had a market!).
nah this device is ****ed up ...
sony homepage says that standby time is around 450 hours .... (more then 17 days!)
i dont have timescape on autoupdate - the only thing i do is gmail push and i get 1 and maybe 1/2 day(s) of standy time (depends if i make 1 call or not )
the update should increase it a lot i think
btw if some1 has a 2nd phone please try this:
charge it fully and then turn it off completely ... after 17 days turn it on ... my bet is it wont turn on coz the akku is totally empty...
I have no Wi-Fi at my hotel and I don't have a data plan. How on earth does it drain this much battery. I'm gonna go turn off every app and try another night just on standby.
Have a read of these...
X10 Power Usage
Battery life improvment thread
Battery Life Guide - Worth a read if you are having issues.
Jesus, what a difference a tweak makes. (Battery)
xperianewbie said:
Hmm... could it be just me? My battery went from 100% to 53% from just staying locked over night (around 9 hours).
Click to expand...
Click to collapse
Good question for you actually, how long have you had the phone? my first 4-5 charges were appauling but it quickly got better and now i could not be happier. more often than not getting 7am - 11pm the next day (whats that, 40 hours or so?) out of one charge, with plenty of go left.
Mine is running RB##26 firmware, rooted and a chunk of apps deleted though.
When i first got mine it was a bit poo, remember for the first 5 or so charges to let the battery go down pretty low and it will improve battery life.
Get runcpu and you're golden.
Sent from my X10a using XDA App
Sounds like you're running 014 firmware - I had the exact same problem until I updated to 020. The whole battery usage profile changed and one hour of standby only uses up 1-2%.
yeah, the 020 u/g makes a difference. I've rooted and overclocked mine, heavy usage on 3g can drain the battery in c12 hours but more than adequate for general usage
I'm a big user. Even with my G1, I was happy with a day's use. Anyone who thinks they're gonna get days of use without a charge is kidding themselves. A smart phone with a big screen us gonna suck juice regardless of what you do. As many an XDA user will tell you, keep your charger or at least the cable with you wherever you are. With FW026 it did help a little, but if you need life from your battery you really do need to sacrifice some of your widgets or updates.
MrZ
Today my battery have gone to 10% in about 10/11 hours, i'm using sip and wireless are active all day, even when it are on standby, installed some apps and played some games, some calls, its good enough, sometimes i get 2 days, depends on what you do, you can do some tricks...
I really like this phone but the battery drain is terrible. I have that verizon extended battery in it(2750mah) but even with that the phone will lose about 10% battery in about 1 1/2 hours during non-use and roughly double that if im browsing the web.
I have Battery Doctor and Juice Defender running at all times and disable anything i dont need to have running. Also, for some reason Battery Doctor does not display my current battery status accurately so i use a basic battery stat widget to know exactly how much battery is left.
Does anyone have any recommendations on what i should do? Apps i should use/not use? Oh and i do keep display brightness down and have done a full cycle charge.
Thanks!
voxigenboy said:
I really like this phone but the battery drain is terrible. I have that verizon extended battery in it(2750mah) but even with that the phone will lose about 10% battery in about 1 1/2 hours during non-use and roughly double that if im browsing the web.
I have Battery Doctor and Juice Defender running at all times and disable anything i dont need to have running. Also, for some reason Battery Doctor does not display my current battery status accurately so i use a basic battery stat widget to know exactly how much battery is left.
Does anyone have any recommendations on what i should do? Apps i should use/not use? Oh and i do keep display brightness down and have done a full cycle charge.
Thanks!
Click to expand...
Click to collapse
I don't know if this would help/is recommended, but I decided to bump charge mine once. It seemed to help me out, but opinion seems to be split on whether it's good for the phone or not. I also use only friends and calender widgets, and about 4 toggles (airplane mode, gps, wifi, mobile). I generally turn off mobile network where wifi is available. I have been off the charger since 8 am and am at 83% with light use (a few texts, a little facebook, etc). I do use Watchdog lite (to watch for misbehaving apps) and autorun manager (to tweak what runs on startup). I should probably also mention that I have the stock battery.
Turn off 3g manual in settings.
Make the Radio do 3G Only.
Put the phone volume half way.
No vibrate when receiving a text and audio play after the text.
No vibrate feed back when touching the home,menu,back and search button Which can be found in settings>sounds>haptic feedback. Uncheck it
-Monky_1
I have a stock battery.
I use the battery monitor widget to keep an eye on battery use and rogue apps. If I go over 50mA at idle, there's something that's running when it shouldn't.
I also have wifi sleep mode after 15 minutes of idle. And I keep blutooth and gps off. Also LTE only since i have excellent coverage here.
And i use Tasker to turn on airplane mode overnight (turns off all radios) and also silence all alarms, lights, vibration...
I get through about a day and a half of normal use no problem. Once cm7 is out i imagine i will get 2 or more days no problem, as it tends to idle at less than 10mA which would be a dramatic overnight difference.
Hi,
For those of you that have Battery Monitor Widget installed, what kind of average usage are you seeing with the phone idle, screen off?
On my old Desire it'd sit at something around low double digits, 10mA or so idle with the screen off...
On my new shiny SGSII it's at about 180mA odd, which may explain why I struggle to get a days usage out of it. I've tried different ROMs (stock rooted, lite'ning, currently on villain 2.4.2) and different modems (currently KG6) and have used Ti to freeze all of the samsung bloatware without any improvement...
What kinds of values are others seeing?
Thanks
Jon
in idle , i get average of 50-60mA .. but after 3,4 hours of idle , i can get it as low as 9-10mA .. running on sensation rom 1.4 .. in normal use , it will hike from 100+ma to 400mA ..
it's actually a bit higher than my last desire HD. which in idle can get as low as 4-5 mA .. i guess that's all depend on the kernel ..
seeing at your idle usage about 180mA, that's definitely have something wrong somewhere. gotta find what apps draining the battery
Just did a test while I was down the gym - with mobile data off, but streaming music to a bluetooth headset, it was down to 60-80mA. Turn it back on and it's gone back up again...
Gtalk is frozen, Latitude isn't signed in... Nothing obvious shows up in Better Battyer Stats.. Other than removing apps one by one, any bright ideas as to how to work out which is the culprit?
I think i read that HTC phones actuality give true mah battery rates where on the S2 it is only get`s estimated.
I fully charged it last night, and left it alone overnight. Perfect signal (local picocell about 10 ft away), pretty much everything disabled, all user apps, samsung stuff frozen - only google apps unfrozen. Background data disabled, bluetooth, gps, wifi off.
After a few minutes, after a short while at 60mA odd it sat idling at about 9mA pretty much all night - used about 8% overnight. I re-enabled background sync, now sat on my desk at work with a reasonable 3G signal it's sat at about 60mA.
Time to start unfreezing apps and see what's draining it!
=jon= said:
Time to start unfreezing apps and see what's draining it!
Click to expand...
Click to collapse
Install 'Better Battery Stats' for that.
Regards.
ithehappy said:
Install 'Better Battery Stats' for that.
Regards.
Click to expand...
Click to collapse
It's installed - I get a lot of events/0 and suspend listed in process, and not that many wakelocks listed...
I've just frozen the samsung email client (exchange) and the associated processes, and my usage has dropped from 60-100mA at idle to under 20 - looks like this may be the culprit!
Going to try unfreezing it and seeing if it goes back up again...
I gave up trying to freeze / unfreeze stuff - too much hassle.
So - did a factory reset this morning, so back to a totally fresh villain install. I even removed my 32G sd card in case that was causing issues..
Disabled automatic app re-installing, and have been slowly setting things back up while watching the juice usage.
Currently with touchwiz and all of the samsung crap frozen, no widgets running, my 2 gmail accounts and exchange activesync configured, and it's idling at about 50-60mA.
It's going to be a pretty drawn out process working out what's causing the drain
Update and FIX!
My phone is no longer draining massive amount of batt life when idle (3-5% after 7 hours of idle), android system usage is now down to 5-15% instead of 78-97% from before.
My fixes.
1. Turn off data syncing
2. Turn off wifi while on the road (so wifi doesn't constantly look for signals).
3. Clear memory
Yes, att installs a lot of bloatware that constantly update for changes.
If killing those services AND disabling data syncing doesn't help your problem, then you have a kernel problem (like myself).
If this is the case, do the following:
1. Take phone back to att and get a replacement
OR
2. Re-flash your android with the STOCK kernel found here
http://forum.xda-developers.com/showthread.php?t=1286432
OR
3. Reflash with cognition x2 (reported to solve a member's problem, I didn't try this myself).
NOTE** This will root your phone, you will NOT get the exclamation mark during boot up, but kernel counter may be at "1" after this process.
Re-flashing my phone AND applying the three tricks I mentioned above worked for me..finally my phone is no longer crippled with crappy battery life and recharging is A LOT faster now.
I must be going crazy but this sg2 is killing me. I got it from Att yesterday and the battery life has been pretty HORRIBLE. (First time android user btw).
The phone will eat up 10% of my batter life after only 90 mins of idle. I checked the battery usage and Android OS is at around 78%!!! How do I fix this problem? I downloaded OS monitor and didn't really see anything that uses a lot of CPU, except for certain files syncing from time to time (but 2-3% usage usually).
Checked with battery spy and apparently the majority of the time, the phone was hovering around 200mhz 70% of the time and not deep sleep.
It's sad to have only 1.5 hours of display time with a battery of 45% left (7 hours total time)...coming from an Iphone 3gs, this is just unacceptable. I almost flashed to the 2.3.5 firmware but noticed it's NOT compatible with ATT's version of SG2.
I see people who have a total time of 2 days AND a screen time with 3 hours with 30% battery left. I wish I can get half that!
Running on 2.3.4, can't be the infamous drainage bug right? Thought that only happens with the 2.3.3s
Wifi on, application sync on, GPS off, brightness at 25%, using live wallpaper (the windmill). No active apps on. Downloaded aim, epocrates, battery monitor, cpu spy, and os monitor..rest of the apps are stock.
Update
According to my CPU spy
For the past hour that the phone was in idle
2:20mins at 1200mhz
4:52mins at 1000mhz
8:33 at 800mhz
1:28 at 500mhz
10:11 at 200mhz
33:36 in deep sleep
Currently Android CPU usage is @ 97%, display time of 7mins(2%)
2h 30mins since last charge (97% charge)..current power is 79%. Did nothing but idling and checking battery life.
So...that's 30 mins out of the hour in which my idling cellphone was hacking the pentagon....
Also the cellphone is a tiny bit warm to the touch (not cold)
I have 35% battery life remaining and have been unplugged for nearly 11 hours. This is significantly better than what I was getting with a Thunderbolt on Verizon, where I was needing to charge after about six hours of use. 11 hours and 35% remaining isn't the best in the world, but it's only been two days. The phone needs a few days to charge and discharge to determine true battery stats and will probably get better.
Being that this is your first Android battery life will not seem great but let it settle in for a few days it should get better.
Sent from my SAMSUNG-SGH-I777 using xda premium
Used Nexus S, LG Thrill, Samsung Focus, Infuse, This is the best Android phone for battery. I have 40% left with normal use (emails, calls, music, read news) at the end of the day. Huraaaaa
Singuy1234 said:
I must be going crazy but this sg2 is killing me. I got it from Att yesterday and the battery life has been pretty HORRIBLE. (First time android user btw).
The phone will eat up 10% of my batter life after only 90 mins of idle. I checked the battery usage and Android OS is at around 78%!!! How do I fix this problem? I downloaded OS monitor and didn't really see anything that uses a lot of CPU, except for certain files syncing from time to time (but 2-3% usage usually).
Checked with battery spy and apparently the majority of the time, the phone was hovering around 200mhz 70% of the time and not deep sleep.
It's sad to have only 1.5 hours of display time with a battery of 45% left (7 hours total time)...coming from an Iphone 3gs, this is just unacceptable. I almost flashed to the 2.3.5 firmware but noticed it's NOT compatible with ATT's version of SG2.
I see people who have a total time of 2 days AND a screen time with 3 hours with 30% battery left. I wish I can get half that!
Running on 2.3.4, can't be the infamous drainage bug right? Thought that only happens with the 2.3.3s
Click to expand...
Click to collapse
If you only got the phone yesterday, its way to early to make any judgments on battery life. Battery needs at least 3-5 days to settle in and build consistent battery stats.
Also, what are you settings? Auto Brightness, Bluetooth, GPS, auto syn(exchange emal, gmail, facebook, etc). If your not using these, they should be OFF. It's easy to manually refresh email, etc.
I've seen some people reporting very high Android OS(over 50%) but still getting solid battery life.
I'm at 1hr display time, heavy texting. 72% left, been unplugged for 12hrs
no people what this guy is talking about is the android os bug. i have it too. hopefully an upgrade or different rom will fix it. my phone has been unplugged 11 hours with only 1 1/2 hour display but android os has ran for 52 minutes and now im at 32% battery life. once this bug gets worked out the battery life will be amazing.
I don't think that there is an android OS bug. My android OS shows as being 42% with 13hrs of moderate use and I am still at 67% battery remaining. This is by far the best battery use I have ever experienced on an android device! My cappy would not even come close to this performance and this is on stock ROM and kernel.
Sent from my SAMSUNG-SGH-I777 using xda premium
I'm very happy with mine, this was the first total drain on a new battery so I know it will only get better.
Total time: 18hr 25min
Display time: 4hr 48min
I think it's the system os, not the hardware. There were a few times when the battery didn't discharge itself at 7%/hour (had it idle for 3 hours and it went down like 2%).
And yes, everything is turned off except the sync app data and wifi. There's no option to turn off 4g btw. It's just weird how sometimes it's in this mode of power drainage, and then sometimes it doesn't drain much..but most of the time, it's draining.
I seriously doubt the phone can only run 2.5 hours worth of heavy usage or 12 hours of standby (it should last days!). If this is "normal" for android, then maybe I should have a visit back to att and exchange for an iphone (and I really don't to!)
Sledutah said:
I'm very happy with mine, this was the first total drain on a new battery so I know it will only get better.
Total time: 18hr 25min
Display time: 4hr 48min
Click to expand...
Click to collapse
that is freakin incredible. i am gonna try a restore or something im down to 28% life. 1:40 display android os 1 hour.
can you please post the cpu total time in android os so i have an idea
VFO said:
I don't think that there is an android OS bug. My android OS shows as being 42% with 13hrs of moderate use and I am still at 67% battery remaining. This is by far the best battery use I have ever experienced on an android device! My cappy would not even come close to this performance and this is on stock ROM and kernel.
Sent from my SAMSUNG-SGH-I777 using xda premium
Click to expand...
Click to collapse
can you please post the cpu total time in android os so i have an idea
VFO said:
I don't think that there is an android OS bug. My android OS shows as being 42% with 13hrs of moderate use and I am still at 67% battery remaining. This is by far the best battery use I have ever experienced on an android device! My cappy would not even come close to this performance and this is on stock ROM and kernel.
Sent from my SAMSUNG-SGH-I777 using xda premium
Click to expand...
Click to collapse
I agree - as I said in the Android OS drain thread, even in "good" situations, Android OS displays way high on our systems. I think it's a reporting bug.
I dropped 2% in 5.5 hours completely idle (sitting on my shelf) last night - Android OS was at over 60%. It seems that so far for me, the higher it is, the better my battery life is.
I drop around 15-20% in 9 hours of being mostly idle at my desk at work - it's a weak-signal location so the radio eats much more battery.
One thing is that unlike first-generation GalaxyS devices and interim ones like the Infuse, the GS2 has a coulomb-counter type of battery gauge. This type of gauge sometimes needs to be calibrated with multiple charge/discharge cycles or it will misreport battery state of charge. (However, when calibrated, it's much more accurate.)
Edit: I do have some power management tweaks in the kernel I'm running, but they don't make that much off a difference except in some high-drain corner cases in my experience. I'll be releasing it sometime later this week depending on how well these antibiotics do their job.
Do i need to install a battery app to see the percentage? or we have a way?
Install this app:
http://forum.xda-developers.com/showthread.php?p=15869868#post15869868
If you see "DataTracker-FD" or "Fast Dormancy" as the top wake lock, go into dialer
dial *#*#9900#*#*
disable Fast Dormancy (FD).
By default, the Samsung Galaxy S II has Fast Dormancy support enabled. One of the goals of Fast Dormancy is to increase the battery life of a device, by limiting the amount of signaling between the phone and the cell network. But, when Fast Dormancy it is not enabled in the network and is enabled on the phone it ironically works the other way around, and actually drains more battery than before.
Click to expand...
Click to collapse
That applies to the I9100.
As far as I can tell, the I777 has FD disabled by default. (This may change once I9100 ROM ports start showing up)
Okay, charged my battery to 97%(I got a beep saying it's fully charged). Idled for the past 2 hours and 22 mins. Battery is at 86%.
According to the battery, my screen account for 2%, and the android system accounts for 97%.
This is a stock phone guys, I have no apps installed!
Entropy512 said:
One thing is that unlike first-generation GalaxyS devices and interim ones like the Infuse, the GS2 has a coulomb-counter type of battery gauge. This type of gauge sometimes needs to be calibrated with multiple charge/discharge cycles or it will misreport battery state of charge. (However, when calibrated, it's much more accurate.)
Click to expand...
Click to collapse
How do you calibrate it?
sweetboy02125 said:
Do i need to install a battery app to see the percentage? or we have a way?
Click to expand...
Click to collapse
Settings > About phone > Battery usage
WillEat4F00d said:
How do you calibrate it?
Settings > About phone > Battery usage
Click to expand...
Click to collapse
I'm talking about live battery display. I installed no lock and have no lock screen to see how many % left.
sweetboy02125 said:
I'm talking about live battery display. I installed no lock and have no lock screen to see how many % left.
Click to expand...
Click to collapse
Just search up "battery indicator" in the Market and you'll get a few to choose from.
I too got mine yesterday and started tinkering around with installing apps and such to test out all functions before I rooted it and move onto cm7 most likely. The 1 things I noticed was that the battery was NOT completely full when it was first turned on at the store so once it got a little lower after playing with it I charged it up overnight. Today the battery was WAY BETTER and was not dead yet. I have been using it NON STOP today, rebooting it, testing it, trying to root it, rebooting some more, some time using tango to test it out, watched a Netflix movie, pretty much taking full advantage of it all day. I finally decided to charge it up and use my Captivate a bit. I didn't keep track of usage and times today but I KNOW it lasted a WAY LONGER time with all I was doing with it than my Cappy. Tomorrow I will check more out possibly before putting on a rom.
So LOOOONNNNGGGG STORY short make sure you charge it up once you get it before messing with it too much and then it will LAST LONGER.
Sent from My KickAss Captivated CM7 OC'd 1.5Ghz/Undervolted
After two nights of completely draining then recharging the battery to full, the battery has gotten significantly better. I'm trying to drain it again before I go to bed tonight but I don't think I'll make it.
I played the entirety of Toy Story 3 on max brightness, and only burned 20% of the battery!
I get about 7 hours of battery everyday through medium usage and my battery drains quite a lot when I am revising and listening to music. I have a 1900 battery instead of the stock 1650 and it does improve battery life but is there anything else I can do? I find it a bit stupid that my battery drains so much when I'm just listening to music!
I am running CM9.
Whats the signal strength like in your area? Aside from the screen (put screen brightness down), 3g seems to drain my battery most in weak signal areas, where the signal bars are continuously on 1 or 0. I put my 3g / data off and my phone can easily go hours before any drop in battery percentage, I got 4 days battery life with 3g off using it sparingly or wifi when i could to check my emails. Only other thing i did was calls and texts, but that was just as a test.
But i like to keep data on, and gps, all the time. I often get 4 hours screen time and approx 24 hours battery life with my 2000mAh Samsung battery.
Aside from that, last time i checked cm9 was a battery drain, may have moved on a bit.
the only real way you can save battery "during use" is with some restraint. Ie turn brightness down if screen is on, listen at lower volumes if it's playing music. The more voltage it's using the faster it drains. So less brightness or volume output = less power used.
7 hours is around the average use for battery life savy users around here. Even with the extended battery I'd say your right about on the money for battery use (based on what I assume you do and don't know at this stage). But there is certainly room for improvement .
Now before I go on, you probably won't notice any significant difference to battery life during use from these steps. My only hope is that in-between use it'll save more power, and squeeze out a bit more usage time for you.
First/easiest thing would be go to check if it's sleeping properly. Just don't use it for say an hour, then go to the battery monitor in settings. Check the screen on and awake times, they should be almost idenical. If there are several awake records in between screen on's, then you have a problem.
If you use sounds like unlock sounds etc, go turn them all off.. this was/pretty sure still is an issue in CM9 (causes audio_out1 to continuously wake up the phone from deep sleep and drains the battery like a mofo). Also getting rid of facebook (if it's installed) will help.. it loves waking the phone for no obvious reason.. even with every form of sync, background data, and mobile data in general turned off .
^^ you don't have to do that step but I'm pretty confident you'd have to anyway, so it's just easier to do it straight up. Then you can look for other problems.
Next, install "better battery stats". If you like to support developers, you can quickly buy it off the market. Otherwise it's free here if you search for the official thread.
Reboot your phone, then leave you phone for an hour or two, then check out whats happening in better battery stats. I'm not going to pretend I unerstand what half of the stuff it bangs on about is, but I digress. Select "since charged" and then check each different tabs of data (partial wakelocks, kernel wakelocks etc). You are really just looking for anything that stands out as a red bar basically. small amounts aren't a real worry/bound to happen. If it's bigger than say 1cm long, it's probably an issue. Then it's up to you to find out what the app/process is doing the damage . So either google or the better battery stats thread will be your friend at that stage. It was obvious what is was for me cause it said facebook but you might have a different experience.
Hope that helps. But the only way that's going to make a real dent would be trying to use it less.. lol.
Oh and if possible, turning on airplane mode would save a bit of battery in use. And of course the obvious ones like turn of wifi, gps, bluetooth, data, auto sync, soft key backlight and anything else you can turn off
Just do it what i say .. Download the full version of app. called juice defender from play store..install it and then see the magic by yourself ..i have been using the same ..it almost double up the battery backup through its advance settings.
Sent from my GT-I9100 using xda premium