Galaxy S II horrible battery life


Recommended Posts

Do yourself a favor before you get all worried about battery...

I just recently picked up an SGS2 LTE from Rogers. And I'm running stock and I have fantastic battery.

First and foremost, you should drain the battery right until it turns off. Leave it off and charge it fully before turning it back on again.

After that your battery is calibrated and you'll find it may not drain as quickly. Set your display to 30% and then auto (This screen is incredibly nice and shouldn't have an issue seeing it at that setting).

I'm a very heavy user. My WiFi is always on because I have WiFi at home, at work and anywhere else I go for the most part. I text a ton, browse constantly and play games randomly throughout the day. Sometimes I have a conversation on Skype. Talk on the phone for 15-30 minutes through the day. As an example I wake up at 6pm take the phone off the charger. I finish work at 7am and I go home to sleep. My phone is sitting anywhere between 25-30% after a full days use!

So, I let it die completely, charged it till 100, and underclocked the CPU to 1.0ghz. Also set a completely black wallpaper. Phone has been on for almost 2 hours and it's still at 100%. lol. Still no service yet, unfortunately. Takes 5 minutes for me to activate a customer line and almost a month for them to activate an employee line. Man. Really liking the phone so far, though.

You tried Siyahkernel?

I haven't, but I'll keep it bookmarked for future reference. I'm using the default unnamed kernel, which is based off of Entropy's. Seems to be working OK for now. Actually, I don't think Siyakernel is compatible with the AT&T version. "Only european i9100 models are supported".

You joking right? Siyah with stock clocks and undervolt is one of the best for battery life - beat out by phenomenal extreme which could be unstable due to its one glove fits all UV'ing.. There were some figures on XDA but I cba looking for them as I'm running ICS atm

You joking right? Siyah with stock clocks and undervolt is one of the best for battery life - beat out by phenomenal extreme which could be unstable due to its one glove fits all UV'ing.. There were some figures on XDA but I cba looking for them as I'm running ICS atm

Nope I ain't joking. I've tried them all, believe me, and for myself, Siyah drained too much for my liking. Love SpeedMod, just wish it supported Voodoo Louder as that is its only fault IMO. Siyah does support Voodoo, so I guess it comes down to preference also.

I installed betterbatterystats to see if there were any wakelock issues, let the phone sleep for about 20 minutes, and it found a partial wakelock by google services which was at 8%. Is that something to worry about?

Is your phone going in to a deep sleep while idle/not in use? Download CPU Spy and it will tell you.

VillainRom 3.0 + SpeedMod kernel K2-19. I get easily 2 days out of it. 3 days when I'm not using it heavely.

And i'm using a LiveWallpaper by the way ...

And of course i'm testing Cyanogen 9 Experimental (Android 4.0.3) for some days, but always roll back to VillainRom for stability until we get the source code from Samsung.

I installed betterbatterystats to see if there were any wakelock issues, let the phone sleep for about 20 minutes, and it found a partial wakelock by google services which was at 8%. Is that something to worry about?

Go into Market settings and turn OFF 'google admob ads', might not be root cause, but this is one that is known.

Is your phone going in to a deep sleep while idle/not in use? Download CPU Spy and it will tell you.

Ah, thanks. Yep, Deep Sleep is working fine. I guess there's no need for worry.

VillainRom 3.0 + SpeedMod kernel K2-19. I get easily 2 days out of it. 3 days when I'm not using it heavely.

And i'm using a LiveWallpaper by the way ...

And of course i'm testing Cyanogen 9 Experimental (Android 4.0.3) for some days, but always roll back to VillainRom for stability until we get the source code from Samsung.

Interesting. By the way, I used the method of rooting without tripping the flash counter. If I want to test other kernels, how can I do that? Do I use mobile odin lite?

Thanks for all the helpful tips, everyone.

If I want to test other kernels, how can I do that? Do I use mobile odin lite?

Thanks for all the helpful tips, everyone.

Easiest way is to grab the CWM zip of kernel, put onto SDCard, and flash from Clockwork Mod Recovery, which you should have if your rooted anyway ;)

Not nessesary, but I like to run the 'kernel cleaning script' beforehand (up to version 1.72 I think), also run from recovery and nice to keep on SDCard if your flashing various kernels :)

Easiest way is to grab the CWM zip of kernel, put onto SDCard, and flash from Clockwork Mod Recovery, which you should have if your rooted anyway ;)

Not nessesary, but I like to run the 'kernel cleaning script' beforehand (up to version 1.72 I think), also run from recovery and nice to keep on SDCard if your flashing various kernels :)

Yeah, I have CWM. So basically I just put the kernel onto the SD card and install it from CWM, and then install the new rom? Seems easy enough.

Also, if you have WiFi, don't bother connecting phone to PC for all this file moving. Grab 'Airdroid' from market, its free, fast, and allows you to simply transfer kernels/roms/files etc to phone from your browser on PC, makes things a lot easier ;) Only time I need a cable to PC for SG II is when I need to use Odin for emergencies, and that's rare lol!

Oh and before you do anything....

BACK UP YOUR EFS!!!

I have ten backups of this, online and offline, and on various devices, overkill yeah, but I learned the hard way I'm afraid, with my phone going back to Sammy, so if you havent already done so, please do it :)

Also, if you have WiFi, don't bother connecting phone to PC for all this file moving. Grab 'Airdroid' from market, its free, fast, and allows you to simply transfer kernels/roms/files etc to phone from your browser on PC, makes things a lot easier ;) Only time I need a cable to PC for SG II is when I need to use Odin for emergencies, and that's rare lol!

Wow, how did I not know about this app. Thanks!!

Got the GS II with CM7 ...

battery goes like this (after about 6 or so months of usage)

Screen (100) = baterry dies within 3-4h (gaming and internet)

Screen (25% - lowest) = up to 8h or so (an entire day)

Light usage but some gaming for short periods of time (low screen) about a day

Deep sleep light usage (about 1% drain over 4-8h or so)

overall I have noticed that the screen just trashes the battery like it is going out of stile otherwise the phone is quite nice ...

mind you, to have the same intensity and usage as an iPhone, the S II falls short by 1/3 and that is with 2.3 OS, have not tried and 4.0

(the bluetooth is off as with the GPS, low CPU freq 200Mhz, high 1.2 (default), never put in airplane mode but always make sure it goes into deep sleep (if not find out why))

This topic is now closed to further replies.
  • Recently Browsing   0 members

    • No registered users viewing this page.
  • Posts

    • Because of what they have done to VMware I will never buy anything Broadcom again.
    • AMD releases hotfix for driver install issues on Windows 10 PCs by Taras Buria Earlier this week, AMD released an important graphics driver update. Version 26.6.2 brought AMD FSR 4.1 support to the previous-gen Radeon lineup, the RX 7000 series, giving users better upscaling tech that was previously locked to the newest GPUs. However, the driver turned out to be a little buggy, with users reporting installation issues on systems still running Windows 10. AMD quickly acknowledged the bug and today released a hotfix to resolve the problem. The AMD 26.6.3 Hotfix update is now available for download from the official website. Given that it is a hotfix release, it has only one change in its release notes: AMD announced the update on its official X account and added that a WHQL driver update with the necessary fixes would be released next week. Meanwhile, users can apply the hotfix or roll back to the previous driver using the official AMD Cleanup Utility. You can download AMD Software: Adrenalin Edition 26.6.3 Hotfix Preview Driver from the official website here. It is compatible with all currently supported graphics cards and 64-bit Windows 10 and 11. Full release notes are available on the same page.
    • With Microsoft now listening to its core audience and acting upon received feedback, fans can finally expect a much better version of Windows 11 than what was available five years ago. Here is to five more years, Windows 11! I guess we all need a good laugh now and again...
    • Amazon Prime Day 2026 deal sees Samsung Odyssey 49" 240Hz QD-OLED monitor at lowest price by Sayan Sen Earlier today we covered a very good deal on JBL's BAR 800 Dolby Atmos soundbar system as the unit is available for just $600 as part of Amazon Prime Day 2026 deals. That's not all though as there are many more discounts to choose from. If you are looking for a high-end monitor, Samsung's 49 inch G9 QD-OLED gaming monitor is a solid deal too as it's currently just $855 (purchase link under the specs table down below). It is a super-ultrawide (32:9) 1440p curved gaming monitor and as such should offer a very immersive experience. The G93SC is a 49-inch QD-OLED (Quantum Dot OLED) screen and that means it should have excellent contrast as well as color reproduction. Brightness is a bit lacking though so if you are looking to set it up in a relatively bright room, you may be better off with something else. Speaking of external light and brightness, the major difference on the G93SC vs the newer G93SD is that the latter comes with Samsung's "Glare Free" technology to reduce glare while the C model packs a glossy finish. The technical specifications of the Samsung G93SC are given in the table below: Specification Value Panel Type OLED Screen Shape Curved Screen Curvature 1800R Resolution DQHD (5120 × 1440) Aspect Ratio 32:9 Brightness (Typical) 250 cd/m² Brightness (Minimum) 200 cd/m² Contrast Ratio 1,000,000:1 HDR Support VESA DisplayHDR True Black 400 HDR10+ HDR10+ Gaming Response Time 0.03 ms (GTG) Refresh Rate Up to 240 Hz Viewing Angle 178° Horizontal / 178° Vertical Color Support 1 Billion Colors Color Gamut 99% DCI-P3 (CIE1976) Adaptive Sync FreeSync Premium Pro / G-SYNC Compatible DisplayPort 1 × DisplayPort 1.4 HDMI 1 × HDMI 2.1 Micro HDMI 1 × Micro HDMI 2.1 USB Hub 3 × USB 3.0 Speakers Built-in Speaker Output 5W × 2 Channels Operating Temperature 10°C – 40°C Operating Humidity 10–80% (Non-condensing) Stand Type Height Adjustable Stand (HAS) Height Adjustment 120.0 ± 5.0 mm Tilt -2° (±2°) to 15° (±2°) Wall Mount 100 × 100 mm (VESA) Included HDMI Cable HDMI-to-Micro HDMI Cable Included DisplayPort Cable Yes Get it at the link below: Samsung 49" Odyssey G93SC Series Curved Gaming Monitor, QD-OLED: $854.99 (Sold and Shipped by Amazon US with Prime) Prime subscription can be cancelled within three business days at no cost. Good to know This Amazon deal is U.S. specific, and not available in other regions unless specified. We only use first-party seller links (at the time of article publishing); ensure that you purchase from a first-party seller link only. Check out Today's Deals on Amazon | or our recent tech deals. Become a Prime member (for Students or SNAP) via Neowin Get Prime Access - Prime for half price (for qualifying Medicaid, EBT, SNAP) Subscribe to Prime Video, Audible Plus, Music Unlimited or Kindle Unlimited via Neowin As an Amazon Associate, we earn from qualifying purchases.
    • Actually Windows 11 is the GUI from Windows 10 X slapped onto Windows 10. Hence the many performance issues and initial limitations of the UI, like all the restrictions on the task bar placement and features. You could not even right click on the Taskbar and bring up task manager when it first shipped. Windows 10X was truly a new OS from the ground up. Basically a lightweight OS that ran containers for various app types. Win32 got its own container. Performance was not good and OEM’s pushed back on it, but wanted a new OS to push Pc sales. Hence Windows 11. https://en.wikipedia.org/wiki/Windows_10X
  • Recent Achievements

    • Dedicated
      Scoobystu earned a badge
      Dedicated
    • First Post
      Tom Schmidt earned a badge
      First Post
    • One Month Later
      D0nn13 earned a badge
      One Month Later
    • Rookie
      +ChiefOfNeo went up a rank
      Rookie
    • One Year In
      Tom Schmidt earned a badge
      One Year In
  • Popular Contributors

    1. 1
      +primortal
      461
    2. 2
      +Edouard
      177
    3. 3
      PsYcHoKiLLa
      123
    4. 4
      Michael Scrip
      82
    5. 5
      Xenon
      76
  • Tell a friend

    Love Neowin? Tell a friend!