yashsingh1/xdaforums huggingface dataset:
[Galaxy Tab 10.1 Q&A, Help & Troubleshooting] pellegj:
Update!

Been 8,5 hours since i took it off the charger. It's been used for 7,5 of that, about 4,5 hours of playing, and transferring about 10GB over WIFI. BT has been on all the time and screen have been on for 7,5 hours. 17% left, and i also tried shutting it down and starting it up again, it still said 17%. So i guess/hope my problems are gone for now.

Gonna let run out of juice and then charge it again and try with pershoots kernel once more.
[Galaxy Tab 10.1 Q&A, Help & Troubleshooting] jzen:
Well...

1.Flashed stock 3.1 rom

2.Flashed doc's slim 6.5 rom

3.charged to 100%

4.flashed pershoot's 1.4ghz kernel

After these steps my tablet is back to normal and runing smoother than ever! Getting great battery life now about 5%-10% per hour drain depending on wifi switch. Been gaming, emailing and browsing for the last 2 hours and only down to 85% :D!

Update: Pershoot just release his reworked kernel, downloading it right now, will flash and then I will report back!
[Galaxy Tab 10.1 Q&A, Help & Troubleshooting] wlighter:
u running on 1.4ghz on demand?
[Galaxy Tab 10.1 Q&A, Help & Troubleshooting] jfcooley:
I dont post much, but ive tried everything in this thread and cant fix this issue. It was fine until i rooted and flashed a ROM.

Frustrated beyond belief.
[Galaxy Tab 10.1 Q&A, Help & Troubleshooting] ivarson_swe:
This trick helped me too. Looking at 10% drop an hour. My only concern is that my p7500 drops from 100 to 99 percent as soon as I pull the the charger. How long does your devices keep showing full charge?
[Galaxy Tab 10.1 Q&A, Help & Troubleshooting] jfcooley:
Not certain but I believe this is normal. My Evo 3D does the same.
[Galaxy Tab 10.1 Q&A, Help & Troubleshooting] Vlad_z:
dropping from 100 to 99 the moment you disconnect charger is fine.

With moderate brightness 10-20% you looking for 10-14% charge consumption per hour.
[Galaxy Tab 10.1 Q&A, Help & Troubleshooting] jzen:
Yep once I unplug my tab its at 99% and stays that way all day unless I use it. sometimes even after listing to music on my break (hour) its still at 99% (screen off of course).

Last night I flashed Pershoot's new reworked kernel, I have it running ondemand 215mhz - 1.4ghz, when screens off it runs at 215mhz, using set on boot also with no issues thus far.

After 8 hours being idle, 1 hour of music listing, 20 min playing dead space, recording 720p video for a half hour and playing with movie maker for another half hour I still have 75% battery left over :D not too shabby!
[Galaxy Tab 10.1 Q&A, Help & Troubleshooting] Vlad_z:
I want to give you guys updates on my findings regarding fuel gauge chip Samsung is using in our tabs.

It's MAX17042. I spend lots of time looking for datasheet but cannot find it. I found some very similar chip but still not exact. It looks like this chip was specially designed for Samsung by Maxim. So any further knowledge was derived from looking at various drivers for different Samsung devices.

Ok, looks like max17042 is utilizing combination of coulomb-counter with impedance tracking algorithm. What does it practically mean?

There is "quick start"/"quick charge estimate" software function but it's not accessible without special cable or kernel software change. If someone wants to try this I can elaborate on that more.

What can we do without any special thingy?

Tab needs to be at rest (turned off) for at least an hour when its empty and then when it charged back. This will let chip to make 2 open circuit voltage measurements.

How to make sure that tab is discharged enough for calibration to take the place? If capacity is off big time then gauge may report SOC 30% but in the fact battery is in 70%, so chip will not execute calibration procedure.

The most sure way to check this is in terminal, execute this command:

cat /sys/class/power_supply/battery/voltage_now

or through adb:

adb shell cat /sys/class/power_supply/battery/voltage_now

your good discharged start point should be anything below 3700 (3.7V). If your tab is telling that you have 0% capacity but voltage is more then 3700 then keep rebooting tab (this will refresh counter for a moment) or just boot in CWM and let tab run/sit there for some time.

Then charge it with power adapter to 100%, you can check voltage at this point - should be around 4100, usually you should be good.

Then shutdown tab for another hour or two.

That's it. You should be good now unless you are still using certain custom kernels.

PS: I have heard cases when SOC miscalculation occurred on totally stock devices, well, I have no explanation for that, but with custom kernels which allow to charge through USB cable - there is a code path to write wrong data into remaining capacity counter stored in the fuel gauge chip.

After it happens and even when you are back on stock kernel then it will take some time for the chip to slowly correct itself or you need to force recalibration outlined above.

Btw, resent custom kernel (from pershoot) does not include charging by USB functionality. Well, there is nothing wrong with that idea. It just Samsung implementation of charging algorithm is not good if such function will be allowed.
[Galaxy Tab 10.1 Q&A, Help & Troubleshooting] wlighter:
Use an app call Baterry Monitor Widget.
[Galaxy Tab 10.1 Q&A, Help & Troubleshooting] Vlad_z:
Yes, you can use apps for checking voltage - if they work, because some of them don't (like CurrentWidget). Those apps literally do the same:

cat /sys/class/power_supply/battery/voltage_now
[Galaxy Tab 10.1 Q&A, Help & Troubleshooting] wlighter:
lolz.. problem with currentwidget is the report is in V instead of mV. Its useless for our purpose...
[Galaxy Tab 10.1 Q&A, Help & Troubleshooting] jfcooley:
OK I'm trying to understand how to do this. I have a question or two.

I tried the terminal command and got not found. I don't know if it matters but ATM I'm using bonsai. I'm dl'ing stock right now.

Tried batter monitor widget and noticed that my GT box says 7,000 mAh battery, but battery widget says 1500 mAh.

So, now I'm more confused than when I started. Can someone set me straight?
[Galaxy Tab 10.1 Q&A, Help & Troubleshooting] Vlad_z:
yes, it matters, means you are using different kernel and I don't now what battery monitor doing in the background (I can disassemble it and take a look but it would take a time)

post result of this command:

ls -l /sys/class/power_supply/battery
[Galaxy Tab 10.1 Q&A, Help & Troubleshooting] jfcooley:
Thanks for replying, but I have the stock installed now. Going to try terminal in a few minutes.

Your command yielded this.

127|app_109@android:/ #ls -l sys/class/power_supply/battery

lrwxrwxrwx root root 2011-08-18 17:26 battery -> ../../devices/platform/p3-battery/power_supply/battery

Edit again: original command works. I didn't notice the space after "cat" . Sorry, clearly I'm a newb with the terminal.
[Galaxy Tab 10.1 Q&A, Help & Troubleshooting] jfcooley:
Followed this procedure last night. Fired up this morning and have been browsing/reading news for an hour or two. Battery drain seems to be back to normal, around 79% as I type this.

Thanks earned and given. This issue has annoyed me since it occurred. I can trace it back to installing a custom ROM. Will be staying on stock rooted for time being.

Thank you again.
[Galaxy Tab 10.1 Q&A, Help & Troubleshooting] pokey9000:
This is the same battery monitor used on the Nook Color. Periodically the Nook would do a dump of some registers holding the battery state, and on boot the file was loaded into the device. More here.
[Galaxy Tab 10.1 Q&A, Help & Troubleshooting] pellegj:
For what it's worth, my tab is now fine from this problem after calibration. I'm on BroodComp ROM with pershoots kernel for the 7500.
[Galaxy Tab 10.1 Q&A, Help & Troubleshooting] galaxy_lighthouse:
ok looks like I've got the same problem on the p7510. Can anyone post me a guide or link to "how do I flash the kernel"? Would be very grateful as I have no idea how to do it the right way.

thx
[Galaxy Tab 10.1 Q&A, Help & Troubleshooting] wlighter:
Just flash with CWM like u were flashing a rom. Wipe cache and dalvik first.
[Galaxy Tab 10.1 Q&A, Help & Troubleshooting] verusevo:
Is there really no other way todo this. Is soooo EFFing frustrating. My battey goes from 100 to zero in MINUTES not hours. I cant just sit here rebooting my tab 1000 times until the battery finally dips below 40%. Ive already tried this method once and i dont know what i did wrong but it didnt work. There relly has to be a better option than me wasting about 8 hours of my life just tryingto calubrate a friggin battery
[Galaxy Tab 10.1 Q&A, Help & Troubleshooting] nikzDHD:
What kernel are you on? After following this method my battery is back to normality.
[Galaxy Tab 10.1 Q&A, Help & Troubleshooting] Vlad_z:
instead 1000 times rebooting you may just boot once onto recovery and let tab stay in it...

I mention this way of discharging in previous post.
[Galaxy Tab 10.1 Q&A, Help & Troubleshooting] novasam:
After much research I guess this is a known issue with flash ROMs on Android in General, just that Samsung's fuel chip added a little extra wrench to the whole mix. I hope my rambling is helpful to someone out there, and it will add to the possible fixes to try out.

Yesterday morning I ran into the battery drain issue on my Samsung Galaxy Tab 10.1 I purchased early July. I had my Tab off and charging overnight, as I usually do. When I powered it on and unplugged it, I had a low battery within a few minutes of browsing the internet. I was using Starburst_TW_8.9.11 rom, with the overclocking. I right away noticed that when I turned it off and tried to charge my tab it was still 100%. So I figured it was an issues with the software.

So I tried flashing back to stock, and a unrooted ROM, which is not much fun after being rooted. I then found an updated TW ROM from Task650 http://xdaforums.com/showthread.php?t=1227800&page=9

Then after searching the XDA site as I usually do (the main reason I almost never post questions in forums) and finding this thread I tried the calibration method, that got me more then 30 minutes of use of my tab, I was able to watch the movie StarTrak and do an hour of browsing, but still dead in the software, and even after a reboot it would power down, even though it was still only 60% dead.

On top of Vlad_z's method I also had to make sure I did a factory reset, and delete cache and everything. I then went ahead and restored most of my Apps without any issues so far. I know this is pretty much a given when flashing ROMs on Androids to make sure the new ROM you are using is clean from the previous ROMs settings. Looks like my issue was a combination of flashing multiple ROMs in a week and the wacked fuel chip.

I left my tab off overnight, and powered it back on this morning to find I can now see the remaining 60% of the battery, I'll update later today or tomorrow if I'm able to drain it down to crtically low levels and charge it back up without issues.

I also want to thank all the Devs for all the resources they provided as well as Vlad_z's and everyone on this thread for their post. Without this site I would have probably still had this issue, one day in stock, but would have to deal with Samsung's support (which is not the greatest my buzing Samsung TV and blueray player are a testiment to that). :P
[Galaxy Tab 10.1 Q&A, Help & Troubleshooting] verusevo:
ok im giving this another shot. I just realized alot of you are sayinf that i should flash back to the stock rom before i do the calibration. im presently on the stage where im leaving it off for an hour before recharging the battery. But my tab is currently running the starburst Rom with the pershoot kernel that seems to be the main culprit in all this. So my question is, Is it necesary for me to flash to stock before i charge the tab and do the battery calibration. Would it be ok if after the (1 hour) but before charging to 100% i run the tab in CWM and flash the stock ROM then charge it fully and leave it off for 5 hours?

also do i hae to stay on stock until this is all figured out?
[Galaxy Tab 10.1 Q&A, Help & Troubleshooting] Vlad_z:
running for 1 hour in cwm maybe not enough. I did not check current consumption in cwm.

In order to start calibration you have to be sure voltage is below 3.7V.

PS: latest pershoot kernel seems not to have such problem. Just don't overclock.
[Galaxy Tab 10.1 Q&A, Help & Troubleshooting] madsquabbles:
doesn't work for me. i've always been on stock kernel. this is also a problem with my 7in gt, so it's seems to be a samsung specific problem as i've never had this on any other android tablet.
[Galaxy Tab 10.1 Q&A, Help & Troubleshooting] novasam:
Quick Update

After draining the battery as low as I could, and recharging I haven't had to recharge in over a day now. I have watched serveral movies and TV shows, it is down to 20%. I would have to agree, don't overclock unless you accept the risk involved. Not that I'm sure it is the cause, sounds more like a bug in the chip and driver.
[Galaxy Tab 10.1 Q&A, Help & Troubleshooting] verusevo:
not sure what to do now. i've done the battery calibration two days in a row now. while the battery has improved drastically its not at ll like it was. my battery lasts about a day now but it's regardless of whether I'm using the tab or not. Yesterday I did nothing but read an ebook using the Nook all all day at different intervals and that drained the battery by days end. Today I opened the browser and watched a flash video online. I put the tab face down without finishing but when I came back to it about 7 hours later the tab was at 25% down from 100 when I started. I I don't know if the browser andscreen were on the whole time but even if they were I don't see why a static screen would use 70% of my battery in that time. Instead of the 10% an hour most people say it should drain at mine seems to be doing 15/20% if I'm actually using the tab. I seriously hope my battery isn't permanently fried as that would really poss me off. I don't want to have to charge my tab as often as I charge my cellphone. Simply because ididnt have to before flashing whatever corrupted rom/kernel started this whole mess.
[Galaxy Tab 10.1 Q&A, Help & Troubleshooting] UKseagull:
Nothing to loose by installing BetterBatteryStats from the market, just to see if it highlights anything.
[Galaxy Tab 10.1 Q&A, Help & Troubleshooting] jfcooley:
Just want to chime in since its been a few days since fixing my battery issue.

I can't provide proof, but my feeling isn't that its the hardware causing this. I can trace back my issue to either flashing pershoots Kernel with starburst, or bonsai. Prior to the switch I had no issues. Unfortunately I went from that flashed kernel to bonsai within a few hours, so really no way of telling.

one thing I do know is that I did a full factory reset, and full wipes, but I didn't wipe battery stats.

I thought about trying to replicate since I know the fix in this thread works. After thinking about it a little longer, decided against the aggravation. Few things have irritated me more than this issue.

Since the fix I've flashed only stock roms, but have used pershoot kernel without issues. Have been overclocked to 1.2 with no issues.

Just thought I'd offer this up in hopes it will track down what causes this.
[Galaxy Tab 10.1 Q&A, Help & Troubleshooting] FallenSB:
I took a backup of my tab right before I installed anything new. If I restore to that backup should i then be at stock everything?

Newb Question I know ^^
[Galaxy Tab 10.1 Q&A, Help & Troubleshooting] 5thElement:
Like Ive been saying, stay away from ROMs made by hobbyist here. This is a major issue and is not hardware related. It kernal and ROM that are causing the issue. I cant emphasis how much more stable and reliable the stock rom is.
[Galaxy Tab 10.1 Q&A, Help & Troubleshooting] slack04:
Hey, can we get that photo of the GT10 microSD slot you found now?
[Galaxy Tab 10.1 Q&A, Help & Troubleshooting] nakedninja42:
Whats your point on being here, xda is all about hobbyists...

Is it your hobby to provide false information that you can not backup with proof?
[Galaxy Tab 10.1 Q&A, Help & Troubleshooting] pershoot:
Stop spreading rumours. You know nothing of max17042 to comment further on this topic.

Stock is so reliable, that you want to eagerly fix that volume issue and status bar color, or is that a feature? Samsung pulling the tw update for sluggish performance and battery issues, guess that's a feature too?

You're losing credibility by the day.
[Galaxy Tab 10.1 Q&A, Help & Troubleshooting] raudis4:
my battery drain seems to be much better now. Now I just need to some help with the volume on this thing. Seems so soft at times.
[Galaxy Tab 10.1 Q&A, Help & Troubleshooting] pinghsien422:
I've got my tab to discharge below 3.7V, and has been sitting there turned off for more than an hour now. Question: Should I turn it on before I start recharging to 100%? Can I turn it on while it is charging? Or should I just charge it to 100% while it stays turned off? Or does this not matter at all? Also, after I charge it to 100%, should I turn it on at least once and then turn it off for an hour? Or can I just leave it off for an hour before turning it on? I am just looking for detailed instruction so I don't screw this up and having to redo all over again.

1. Discharge to < 3.7V.

2. Turn off tab for an hour.

3. Turn on the tab (?)

4. Plug the tab in and charge.

5. Turn on the tab (?)

6. Wait until tab reaches 100%.

7. Turn on the tab (?)

8. Turn (or Leave) the tab off for an hour.

9. Turn on the tab and DONE.

Thanks
[Galaxy Tab 10.1 Q&A, Help & Troubleshooting] Evan2ac:
I got this issue when I flashed Task650 ROM. Had my battery drain overnight twice in one week. I switched back to stock ROM and never had an issue since. Luckily my battery and battery calibrator was not damaged.

This is a software issue related to aftermarket ROMs and kernels that can seriously screw up your battery and battery calibrator.
[Galaxy Tab 10.1 Q&A, Help & Troubleshooting] pershoot:
i call bull**** once again.

learn how to manage your background processes, and that won't happen.

let me remind you, it is frowned upon to post under another alias, when your primary one has ben banned, not once, but twice.

you are skating on thin ice, and are deemed quite lucky i have not reported you at this point.

cease this holier then thou, stock is the holygrail attitude, or i will have no choice. contribute something positive not negative. i hope you are old enough to understand that.
[Galaxy Tab 10.1 Q&A, Help & Troubleshooting] Evan2ac:
Please stop attacking me. I am posting MY experience. I made SURE all background processes were killed every night and I even check CPU usage to make sure there wasnt a process stuck eating CPU cycles. It is now two weeks since I flashed back to stock ROM and I have never experienced the battery drain issue since Task650 ROM and I am thankful my battery isnt screwed up like others here.

This is MY experience and if you dont like to hear it well then this is just tough. You cant sensor information just because it dosnt adhear to your liking. Background apps are not the problem here.

Do I know what is causing the problem ? No. What I do know is that aftermarket ROMs/kernels are causing the issue as I have experience.

This is a SERIOUS issue which screw up your battery as people are finding out now.

As I said before I am giving my experience so that people can make a decision. If its worth the risk of damaging your battery then go ahead and flash all the ROMs you want. Until this issue is investigated and fully resolved I believe there should be a warning about flashing ROMs other than stock ROM from Samsung.
[Galaxy Tab 10.1 Q&A, Help & Troubleshooting] pershoot:
please stop attacking everyone on this forum. this is the most serious offense anyone can do.

i will continue this as long as you continue your negative attitude and outlook on these forums.

i am going to pick apart every nook and cranny of every one of your posts. start proving your words, instead of speculating. something not working right? help! instead of saying, stay away.

contribute something positive, and this wont happen.

show your true identity; oh wait, you can't. you've been banned twice. wonder why. androidforums.. banned too. wonder why..

are you ready?
[Galaxy Tab 10.1 Q&A, Help & Troubleshooting] pinghsien422:
Please chill out guys, there's no need to be fighting. Evan2ac is just in posting his experience. I don't believe it is a criticism aimed towards anyone specific, so there's no need to feel defensive.

Being a software engineer myself I know how difficult it is to write a bug-free piece of code, and I'm thankful that all of you developers at xda putting all the effort to pick up samsung's slack and making fixes and improvements to the stock ROM. However, I do realize it is not impossible to introduce new bugs in the process.

I too, after trying out numerous ROMs and kernels, I settled for Starburst ROM with pershoot kernel in the end, after which I started noticing quick battery drain. This does not necessarily mean the after-market ROMs and kernels are bad. It could be due to a combination of old data, plus the flashing process, plus the new ROM/kernel that causes this. No one knows for certain unless they know all the stock ROM/kernel code, state of the device during flashing, hardware drivers, and the custom ROM/kernel code inside out.

We're not here to debate whether after-market ROMs are good or bad or whether one should use them or not, we're just here to share our experiences, and also seeking support that's all.

EDIT: BTW, can someone help me with my question in the previous page please? ;)
[Galaxy Tab 10.1 Q&A, Help & Troubleshooting] pershoot:
evan2ac is posting under a false alias. his real alias is 5thelement (i gather; not sure if there are other numerous aliases out there), who has been banned from here twice. his current alias has been banned from androidforums.

there is a difference between posting about an experience and helping, or posting about an experience, shoving it down someone's throat, and expect that everyone follow lead; mock others for thinking and experiencing differently.

the former is what this community should be about. otherwise, we gain nothing and we don't move forward.
[Galaxy Tab 10.1 Q&A, Help & Troubleshooting] pinghsien422:
You sure about that tho? I did read the previous posts by 5thelement and I agree with you that he should be banned. However I'm not totally certain evan2ac is 5thelement. His first post was simply stating that he started getting the battery drain issue after flashing custom ROM, which I did too. I think it is natural for any non-tech savvy people to quickly jump to conclusion that custom ROM is the culprit to blame. (Which is in fact a possibility, but not certainty.)

So, now can someone now help me with my question in the previous page? :p
[Galaxy Tab 10.1 Q&A, Help & Troubleshooting] pershoot:
check his first post in the dev forum and then a followup in the general, and posts therafter and compare the wording/flow/grammar. they are quite similar.

then a quick cross reference on the other forums; they all gel together.

everyone who flashes anything agrees to certain terms (whether written or unwritten). there is always potential for some bug, however small or big that may come up. it is the nature of the technology. flashing and then turning around and being a (vocal) critic without being constructive, holds things down and turns things in to a regression, so to speak.
[Galaxy Tab 10.1 Q&A, Help & Troubleshooting] pkoper:
Cheeky developers smuggling those pesky battery drainage scripts into the roms.... how dare they... :-)
[Galaxy Tab 10.1 Q&A, Help & Troubleshooting] Vlad_z:
For fg chip to calibrate itself current should be small enough so change of voltage would be less then 2mV per minute or something like that. I don't remember exact number.

So, to be on safe side, if you have it off for 1 hour when battery voltage is low 3.7V. I would say, charge it as is - when it is off and then keep it for one more hour when it's done charging unplugged.