Horrid battery life?Support

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  1. sushifor5

    sushifor5 Well-Known Member

    I have the 3g nexus 7 and live in an area with not the greatest reception, but it is pretty stable. I'm not rooted. I'm only getting 4.5 hours of use on my battery (that's me using the tablet, not sleep) and that seems bad. Is it?

    I have everything turned off that i know how...No auto syncs on, no wifi, no latitude on, no gps, just my att 3g mobile connection and i put it in airplane mode when not using. I mostly surf the web with chrome and rarely stream video with xscope, i use a weather widget with manual updating, eBay app, pure grid calendar. I don't play games.

    When i look at the nexus battery stats, it says screen is using 75%. I keep my screen brightness as low as it can go at all times. When i check gsasm battery monitor, it shows that the app "mobile data" has performed 1168 wakelocks. Of course, i don't even know what that means... Techno dummy here.

    I have read a bit online and can't find anything applicable that i can understand. I've read about deep sleep. Is that a potential problem... Lack of deep sleep? How do i check my tablet's deep sleep pattern?

    I would be very grateful for any advice on how to figure out what is causing my battery problems and how to fix them! TIA!

  2. Kamal Hans

    Kamal Hans Active Member

    Hi, I suspect its the 3g always being on which may be causing the problem.
    I have a wifi only N7 but I think if you were to go to Settings>WiFi & Networks, there would be a tab for Mobile or 3g Network.
    If you touch that , some options should open up-3g always being on/being off when the tab is in sleep etc
    Select the mobile/3G being off when the tab sleeps option - this is what I've done with my wifi settings, viz wifi being off when the tab sleeps.
    Also,in case you do not have/are not using wifi at home, turn the wifi slider button to off so that the tab doesn't keep hunting for a wifi network- that can dplete the battery significantly.
    Plz try these tips & see.
  3. sushifor5

    sushifor5 Well-Known Member

    Well, I always put the tablet in airplane mode when I'm not using it for web stuff and I don't need data and when I'm not using it at all. Isn't that the same thing? I have wifi always turned off since I don't use wifi. Any other suggestions? Thx lots!
  4. El Presidente

    El Presidente Beware The Milky Pirate! Moderator

    The WiFi radio uses much less battery it's 3G counterpart, I'd use WiFi when/if you can.

    Also, dependant on your signal strength, 4.5 hours of screen on time if you're constantly browsing (potentially) sounds about normal.

    If you don't have a great reception, the OS will push more power to the radio in an effort to get a better signal which will obviously impact your battery life negatively. The poor signal might explain why GSAM says mobile data is the biggest battery hog.

    If you were to put airplane mode on and just leave your tablet alone for a couple of hours, what's your battery like?
  5. Kamal Hans

    Kamal Hans Active Member

    I've been getting approx 10 hrs battery life between charges, on my Wifi only N7.
    And I always boot up when I want to use the tab & shut down when I'm done, i/o putting it to sleep, which is what most users seem to do & recommend- its a cultural thing , I guess!
    And I don't use it for listening to music/podcasts i.e, activities where the screen can be off; all of my usage- reading, browsing, watching videos.
    All I've done is turn off auto syncing/ updates/notifications/location finders etc everywhere; manual refresh is fine with me,& I turn off GPS/Bluetooth/wifi (e.g. when I'm reading a book or a very long article etc), when not required.
    While I wholeheartedly agree with El Presidente's comment on wifi being less battery demanding than 3G, I still think that in your specific case, having 3G on all the time may be the culprit; the high number of wakelocks point in that direction
    Try turning it off when you're not using it/when the tab is sleeping/at night when you're sleeping & see.
    Lastly, I cannot recommend the 'Better Battery Stats +' app( avbl in the play store) too highly for identifying activities/apps which are chewing up the battery in the background.
    Try it, you won't regret it.
  6. trankster

    trankster Well-Known Member

    Similar to other comments about the WiFi model, I have had pretty good battery life on my N7. It is comparable to my smartphone and former Samsung Galaxy Tab 10.1 (wifi only). Usually around 50% left after 12-15 hours of use. I receive emails throughout the day, have screen on 2+ hours for reading, email, web browsing. I sometimes stream Pandora to a remote speaker via Bluetooth for over an hour at a time, and have not noticed any unusual drain. The only time I noticed serious battery drain is when I watch a movie. In that case the battery is good for maybe 4 hours of continuous use before it is down to around 10-15%.

    There are several things you can do to save power including keeping your screen brightness low, putting it in Airplane mode when you do not need 3g, wifi or Bluetooth. I use the auto brightness and the Screen Filter app set at 70%. Use a battery status app or check Battery in settings to see what is using the most power. There are some apps that run in the background and drain your battery. You may be able to spot these by checking your battery status. It may be that 3g is the problem. I suggest using a power manager such as Juice Protector or GreenPower (which I use). This has helped extend the battery on my phone which is always on, and often in weak cell zones.
  7. sushifor5

    sushifor5 Well-Known Member

    Thanks for all the input. I don't have wifi, that's not an option. I only use the 3g when doing web stuff, which sometimes is a few hours. When I'm not using web, I'm always in airplane mode, which i assumed shut off mobile 3g connections?

    By screen time, I'm assuming you mean time I'm actually looking at something on screen, like browsing or reading or watching video... My brightness is always set to lowest.

    If I'm not using the tablet, it's in airplane mode just sitting there, and i seem to get 9 or 10 hours out of the battery, haven't yet timed it. I have gsam battery monitor, which showed me the mobile data wakelocks. No apps are showing up as big battery drains, but screen is always about 75%.

    I did install watchdog app and cpu spy yesterday. Can someone explain deep sleep to me? Last night, while i slept, tablet started with full charge, not plugged in, on airplane mode, doing nothing... And when i checked it after getting up today, battery was at 50% and cpu spy said it had been in deep sleep only one hour. Is that bad?

    Thanks much... I'd like to understand the workings of all this better.
  8. Kamal Hans

    Kamal Hans Active Member

    Its indeed bad; 50% depletion while the tab is in sleep mode is totally unacceptable.
    In comparison, my tab dropped only 1 % while it was in sleep overnight.
    Deep sleep means that the tab does not wake up to carry out ANY process whatsoever at any time while it is sleeping;hence, in deep sleep there is very little battery depletion- about a %age point or so,max.
    My suggestions are repeated:-
    1) Go to Settings>3G/Mobile , then touch the 3small vertical squares in the top right corner of the page, click on the advanced tab in the drop down menu & choose never from the options on keeping 3g on during sleep.
    2) For good measures, tonight please manually put 3g off before putting the tab to sleep & then check battery %age depletion the next morning.
    3) For another good measure,go thru the settings of each app which is not a system app & turn off notifications & background sync.
    4) Ensure that you have location services off.
    5) Plz do consider installing Better Battery Stats + app to check which apps are responsible for the wakelocks & partial wakelocks to identify the culprits- I was astonished how many apps were using partial wakelocks for location etc while the tab was in the sleep mode , after I installed BBS+.unchecking the relevant settings made a significant diff.
    Plz consider trying the above mentioned steps.
    sushifor5 likes this.
  9. sushifor5

    sushifor5 Well-Known Member

    Will do those suggestions, thanks. Oops, i just looked and i don't have the settings option you described for 3g. If i knew how to take a screen shot, I'd try to show you what mine look like... My settings menu for Wireless and Networks has wifi, Bluetooth, data usage and more. Under data usage is my 3g info and the menu in it doesn't have any options for turning off during sleep.

    I thought the nexus 7 is advertised for 9 hours of web surfing. Is that correct? Wouldn't that be screen time? Is 9 hours possible?
  10. jhsrennie

    jhsrennie Well-Known Member

    I don't use the tablet for web surfing for long periods, but if I'm using Currents I find the battery drops between 10 and 15% per hour, so 9 hours web surfing seems plausible. That's via Wi-Fi and with the screen brightness set low though not ridiculously low. I don't know if 3G is hungrier on battery than Wi-Fi.
  11. Kamal Hans

    Kamal Hans Active Member

    Will do those suggestions, thanks. Oops, i just looked and i don't have the settings option you described for 3g. If i knew how to take a screen shot, I'd try to show you what mine look like... My settings menu for Wireless and Networks has wifi, Bluetooth, data usage and more.
    Tap Wireless and Networks, you will see Mobile Networks; under Mobile Networks you would be able to find the setting to turn off the 3G,while your tab sleeps.
    I thought the nexus 7 is advertised for 9 hours of web surfing. Is that correct? Wouldn't that be screen time? Is 9 hours possible?
    Oh yes!
    If you read thru a prev post of mine, I used to shut down) not put it to sleep) my N7 after use & boot it up when I wanted to use it.
    Hence, the screen used to be on all my usage time, given that my usage pattern consisted of activities which required the screen to be on - i.e, reading/browsing/ you tube etc.
    And I used to get around 10 hrs between charges.
  12. El Presidente

    El Presidente Beware The Milky Pirate! Moderator

    You might want to try turning location services and Google Now off, they're both known to be battery hogs too.
  13. Kamal Hans

    Kamal Hans Active Member

    The BBS+ app is great for identifying all such apps which keep waking up the tab even when it is supposed to be sleeping.
    Disabling such hidden/background processes makes a huge diff to battery life.
  14. sushifor5

    sushifor5 Well-Known Member

    Yes, both have been off since i got it, as i don't use them... I've turned off everything i can find to control... always open to more suggestions, though. Thx!
  15. sushifor5

    sushifor5 Well-Known Member

  16. sushifor5

    sushifor5 Well-Known Member

    That's interesting... I sometimes use currents, i have it set on no auto updating in background, is there another way to curb its battery consumption?
  17. sushifor5

    sushifor5 Well-Known Member

    The good news is that cpu spy shows my tablet has been going into deep sleep all the hours i have it dormant (and in airplane mode) while I'm sleeping. I'm assuming that's a good thing.

    My nexus had been 17 hours on battery now and has 63% battery left, but I've only been using it for 60 minutes (web use). Rest of time it was "asleep." Stat says screen using 86% of battery.

    All other stats look good, no battery hogging apps seen. Mobile data, eBay and phandroid have highest number of wakelocks (400ish each), and those are the things I've been using... 3g, eBay and this forum app.
  18. Tethered

    Tethered New Member

    I have the Wi-Fi only N7, and the battery life tends to depend on what I use it for and who's using it. It will live up to its promise of 9 hours and then some if I do almost nothing with it, but continuous web surfing (without watching videos or listening to music), and the battery life does drop significantly. I'll be past 50% after nearly three hours. Yet when I hand it over to someone else to do the same (including watching videos and music), it will last longer. I don't get it.

    Right now it's at 39% after 6 hours and 45 minutes of use on battery. It's dropping down 2% every few minutes of being idle. I wonder if this is normal.
  19. El Presidente

    El Presidente Beware The Milky Pirate! Moderator

    2% every few minutes isn't normal. I can take mine of charge, not touch it for 8 hours and I'll have only lost 5-6%.

    Is your WiFi signal poor? You might have a rogue app running in the background, chewing through battery. Install something like GSAM Battery monitor, let it run for a bit and see what's eating in to your battery life.
  20. Tethered

    Tethered New Member

    I did just that today, used my tablet for a few hours (I spent the majority of the time web surfing, and it got to 6 hours and 11 minutes with 29% left). When I check the battery usage stats, the screen is always what's using most of its power at 67%.

    Here's a screenshot of the app monitoring my use:
  21. Tethered

    Tethered New Member

    ^^^ Whoops, disregard the screenshot in the last post, I downloaded the wrong app. Here are the stats with the GSM battery monitor:

    I don't appear to have any rogue apps (in fact I have few apps that aren't preinstalled), and as you can see it's the screen itself using up most of my battery. I always have Bluetooth turned off when I'm not actively using it, I keep the screen dimmed at the near lowest setting, and I don't do anything intensive beyond surfing the web on two different browsers. I don't know what else is going on.
  22. El Presidente

    El Presidente Beware The Milky Pirate! Moderator

    It looks as though you've used it quite heavily there, what happens if you let GSAM run whilst the tablet is idle for a while.
  23. Tethered

    Tethered New Member

    It's pretty much the screen that seems to be the culprit, it barely uses up any power when it's idle.

  24. bob60626

    bob60626 Well-Known Member

    Fwiw, while I also use airplane mode often, the Sam Lu 2x Battery app is useful when I have data on my 4 g 7.0+. I didn't like it on my phone so much.
  25. sushifor5

    sushifor5 Well-Known Member

    My screen also is what shows up as eating most of my battery, at 75% consumption, and I always keep my screen on lowest setting. I don't get it, but then I don't get technology, lol.

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