Poor battery life aargh

[emmellar]

My battery life is terrible!  Not running any background apps and Bluetooth off.  This is a 32 GB with 3g.  Any thoughts welcome but I think I have a dud on my hands



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[LeoRex]

Almost looks like a junk battery... 

Sent from my SCH-I200

[bjs229]

Almost looks like a junk battery... 

Sent from my SCH-I200

Did you get 8 hours of use before you started charging? How bright do you have your screen set at? Did you just notice a change in battery life under the same conditions of use? How many hours of  your use are you getting from a full charge compared to what you are saying is poor?

Why do you say it almost looks like a junk battery? There are a lot of variables that are or could be in play before its narrowed down to a hardware issue.


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[matt]

Looks like you got only 2 1/2 hours of actual use (screen on). Most of the drain was the wifi and mobile staying on while the tablet was supposedly asleep. I don't have the 3g but in settings, wifi, menu, advanced, you can set the wifi to turn off when asleep. As far as the awake spikes while the screen was off, turn off auto sync in currents, locale, weather etc. On google play is a program called 'wakelock detector' to help track those down. Look at the partial wakelocks (screen off activity).

[bjs229]

I am a little confused with the numbers. You have 38% left but it is charging. It says you had 8 plus hours of use and 2 plus of it was the screen being on. How much actual percentage of battery was used while you were using it for games and whatever. Like Matt suggested. Be careful of apps syncing in the background and take more control of things running while the machine is asleep. Live wallpapers, daydream and such. I disable NFC as well. Is your screen brightness turned all the way up?

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[matt]

The 39 % charge is because when the tablet got to near 0% it shut down or was turned off. Then it was charged to 39, booted, and the screen shot taken. Notice the vertical spike on the charging graph, when asleep that would have been a gradual rise.

I believe the 2 hours and 29 minutes on the second screen capture was his actual use. Plenty of battery posts on this site, tracking these suckers can get aggravating.

[bjs229]

My head spins when trying to figure out these battery equations.

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[LeoRex]

I suspect a dead battery because of the battery getting so killed while the 7 is sleeping...  as if the battery isn't charging fully or misreporting it's status. 

It could also be a very poor Wi-Fi connection...  a good strong WiFi will sip juice, but if the signal is weak, it visits the signal.

Try this:  charge it fully, put it in airport mode, and leave it with the screen of...  if the battery doesn't bleed, it's your 7's WiFi...  if it still kills it, there is some other source

Sent from my SCH-I200

[emmellar]

Thanks for all the comments.  Yep matt is right about the 38% thing.

No auto sync on anything and I am running things stripped back I.e. no current, no daydream, basically nothing that runs in background - I'm a bit OCD in that respect!  I have since posting installed wake lock, turned off 3g and left it in sleep.  Below is result.  Not sure what it tells me except why is mobile signal still shown?



I will try WiFi off in sleep now and see what drain down is like.



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[bjs229]

Did this just start to occur ? Hate to mention the word hard reset but sometimes these battery issues call for one.

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[emmellar]

I got it second hand last week.  Six weeks old and as new.  However who knows how it was initially charged and discharged...

What do you mean by hard reset?  I have flashed various ROMS to see if that would help and have done quite a few factory resets through clockwordmod recovery bootloader...is that the same thing?

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[emmellar]

Have discovered that turning mobile data off does NOT turn off the actual cell signal.  Which is why the signal bar is continuously on in the last set of screenshots.  However if I turn on airplane mode and then WiFi back on this kills the cell signal while still letting me browse in the house!  Not exactly slick and shouldn't need such intervention but let's see what that will yield battery consumption wise before I turn WiFi off also.



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[matt]

Not really seeing why the tablet was waking when the screen was off. Do you have your apps set to auto-update in play? Notifications for email, messages, google voice? The router may need some config if it is constantly reconnecting.

[emmellar]

Getting somewhere.  See screenshot below.  This is after switching into airplane mode, turning wifi off when asleep and thgen putting to sleep for the last hour.  Play update was always off and dont have voice or messaging apps installed.  All mail syncs turned off.



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[matt]

I think you've done it. There's an app called battery widget reborn several on this site recommended. You can set a 'night mode' that turns off background sync and all the radios. It allows mine to consistently fast charge and gives some useful battery info. I'm buying it when the demo runs out.