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Tablet shutdown around 40% battery


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#21 9008

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Posted 06 January 2013 - 09:57 AM

Please somebody solve this problem I hated my tablet since october

#22 michpan

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Posted 07 January 2013 - 07:57 AM

echo B820 > /sys/devices/i2c-2/2-0034/axp20_reg
(or actually "echo B8A0 ...") and reboot,
and if necessary
echo 0800 > /sys/devices/i2c-2/2-0034/axp20_reg

Don't get it.. Should I type all of them? What does "or actually" mean? And how do I know if the last one is necessary?


Michael

#23 Billcnz

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Posted 07 January 2013 - 01:07 PM

Don't get it.. Should I type all of them? What does "or actually" mean? And how do I know if the last one is necessary?


Michael

Sorry that's not very clear, I copied from another post. It's using the echo and redirect command > to send instructions to the axp20 register. It was originally posted on the Ainol Chinese forum but copied on other forums, have a look here:

http://caveat emptor.com/forums/topic/441-100-battery-problem-solved/

Link above was meant to be to *caveat emptor forum but my post keeps getting changed by the forum bot.

Damn, it changed my edit again! Looks like it doesn't like that other forum that starts with Ainol and ends with Store

Sent from my Novo7Flame using CM10.1 and Tapatalk HD

Edited by Billcnz, 07 January 2013 - 01:31 PM.


#24 Tzul

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Posted 07 January 2013 - 01:59 PM

Don't get it.. Should I type all of them? What does "or actually" mean? And how do I know if the last one is necessary?


Looks like someone copied this post by me, but without the explanation at the end.

Anyway, this is a workaround for older firmwares with the "battery stuck at 100%" problem. It will probably have no effect on newer firmwares with the "shutdown at XX%" problem.

#25 xer0backlash

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Posted 07 January 2013 - 11:59 PM

Hello. I'm need help. My tablet Ainol novo 7 fire does not turn on, even in stock recovery and bootanimation. It happened when I surfed on internet,tablet unexpectedly freezed and I can see bootanimation. She repeated one minute and and after that she freeze and tablet is off. After that I can't turn on him and recover him. Please help.

This might help you: http://www.slatedroi...n-android-logo/

#26 ralleweichs

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Posted 23 January 2013 - 02:32 AM

Hi, everybody! I think I found a workaround to get rid of the shutdown problem.
Problems:
a) the driver has a bug and is not in sync with the chip
B) the magical charging without a power source
c) the combination makes the tablet unreliable (mine shuts down at 33%)
Do this:
1. Uninstall all battery apps or calibration apps; they are useless for our tablets because they all use the buggy driver info to do their calculations.
2. Install the app “battery monitor” by Sim2k from Google Play. Unlike all the others, this app is voltage based and relies on true system values.
3. Use the widget and configure it through the app as follows:
In the main menu go to “battery” and check the “Voltage Based” box, set the “MIN” value to 3400 and the “MAX” value to 4200 (for a start; you can experiment later!)
4. Customize the widget and choose further functions like notifications and (very useful!!!) alerts starting at 15%.
You will easily find out that the %values will be different from the system values – and that is good! You can now forget about the system “calculations”.
With these settings and close examination of the voltage readings from the “battery shell script” I was able to get the following results on my Flame for the last 15-20 minutes before shutdown:
script: 3439 mV = app 13% system 52%
script: 3404 mV = app 10% system 40%
script: 3342 mV = app 3% system 38%
script: 3173 mV = app 1% system 33% and “unexpected” shutdown 10 seconds later.
Remember: this does not solve the problem of the driver bug, it just compensates for its effects and gives us reliable info on power status. And you will hardly experience the “magical charging effect” again.
Have fun!

#27 chepito

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Posted 23 January 2013 - 06:23 AM

thanks Ralleweichs, this is very usefull

#28 xris5

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Posted 23 January 2013 - 03:14 PM

Thanks ralleweich, but only one thing, the fire's battery isn't 5000 mah instead 4200?

#29 ralleweichs

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Posted 23 January 2013 - 03:24 PM

Thanks ralleweich, but only one thing, the fire's battery isn't 5000 mah instead 4200?


Relax! I'm talking about voltage (mV), not capacity (mA). The fire's capacity is 5000mA, its voltage is 3,7V (= 3700 mV).

#30 xris5

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Posted 23 January 2013 - 03:31 PM

Relax! I'm talking about voltage (mV), not capacity (mA). The fire's capacity is 5000mA, its voltage is 3,7V (= 3700 mV).

OK, sorry for mistake

#31 Tzul

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Posted 23 January 2013 - 05:44 PM

Relax! I'm talking about voltage (mV), not capacity (mA). The fire's capacity is 5000mA, its voltage is 3,7V (= 3700 mV).


Actually, mAh is capacity, mA is electric current.
By the way, I hope you are "BeanLaden" in a certain forum, otherwise you stole this tip. ;)

#32 ralleweichs

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Posted 24 January 2013 - 01:42 AM

Actually, mAh is capacity, mA is electric current.
By the way, I hope you are "BeanLaden" in a certain forum, otherwise you stole this tip. ;)

Dear Tzul,
thank you for the correction! Happened in the heat of the moment. Sorry!
But, by the way, don't we all sometimes suffer from split identity? :db: Some of us even make spelling mistakes in their nicknames! ;) ... and some people in the world have problems with "certain" nicknames, so it is sometimes better to use an alternative one.
Yes, it's me! I posted this tip in a "certain" forum, in a "certain" language, but in this "certain" country hardly anyone uses Ainol tablets.
That is why I "spread the word", hoping to help a lot of people on the planet. :angel:
Grüße
Ralf

Edited by ralleweichs, 24 January 2013 - 01:48 AM.


#33 NeB

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Posted 24 January 2013 - 11:25 AM

Many thanks for this, really usefull !!
Wife will stop bitching at me because the tablet shut down while she was playing a hard level on candy crush saga lol

#34 ad23

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Posted 24 January 2013 - 03:21 PM

since my ainol 4.1.1 jb is under fire, it goes out more than 40%, but is beyond the 14%.
I no longer have the rotation of the screen and the volume lower.
I also lost the touch screen to unlocking but prior to this, the problem is elsewhere

#35 entity1

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Posted 25 January 2013 - 10:49 PM

Hi, everybody! I think I found a workaround to get rid of the shutdown problem.
Problems:
a) the driver has a bug and is not in sync with the chip
B) the magical charging without a power source
c) the combination makes the tablet unreliable (mine shuts down at 33%)
Do this:
1. Uninstall all battery apps or calibration apps; they are useless for our tablets because they all use the buggy driver info to do their calculations.
2. Install the app “battery monitor” by Sim2k from Google Play. Unlike all the others, this app is voltage based and relies on true system values.
3. Use the widget and configure it through the app as follows:
In the main menu go to “battery” and check the “Voltage Based” box, set the “MIN” value to 3400 and the “MAX” value to 4200 (for a start; you can experiment later!)
4. Customize the widget and choose further functions like notifications and (very useful!!!) alerts starting at 15%.
You will easily find out that the %values will be different from the system values – and that is good! You can now forget about the system “calculations”.
With these settings and close examination of the voltage readings from the “battery shell script” I was able to get the following results on my Flame for the last 15-20 minutes before shutdown:
script: 3439 mV = app 13% system 52%
script: 3404 mV = app 10% system 40%
script: 3342 mV = app 3% system 38%
script: 3173 mV = app 1% system 33% and “unexpected” shutdown 10 seconds later.
Remember: this does not solve the problem of the driver bug, it just compensates for its effects and gives us reliable info on power status. And you will hardly experience the “magical charging effect” again.
Have fun!



tested this out. followed every instruction, saw my tab's battery at 35% on main bat app (28% on the battery monitor app), kept wifi on, after 20minutes on sleep checked it again and it shutdown and is saying it has no charge. maybe it only works if you don't have wifi on?

#36 ralleweichs

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Posted 26 January 2013 - 05:33 AM

Good morning, everybody!

to entity1:
On my tablet it does not make any difference whether wifi ist turned on or off during sleepmode. The notifications (if activated) will remind you, if your battery runs out of power.
I'm afraid you will have to start changing the MIN/MAX values in the battery app menu in small steps of 30-50 mV. It is also helpful to use the "battery shell script" to check the proper system info on voltage and chip info in contrast to driver info. The best settings for the battery in my device are 3450 MIN and 4150 MAX. I also found out that a range of 700mV between MIN and MAX is best.

I suggest this strategy:
- With the app and the widget installed, fully charge the battery with the tablet completely turned off.
- Restart and check the voltage displayed in the widget and use this as your MAX entry in the app settings.
- The notifications should start around 3.4 - 3.5V.
- Use the tablet until voltage is down to around 3.3V and see whether the app's percentage is lower than 5%. If it is, your are there. If it is not, adjust the MIN setting (50mV up or down) and check the widget info until it shows values below 5%. You do not have too much time for this because the tablet will shutdown soon after voltage has fallen to 3.2V!
- After the next full charge cycle you can check whether the widget shows 50% when voltage has reached 3.7 - 3.8V. Also take into account that there is an offset of 70-80mV between the calculations of the script and the system calculations of the voltage monitored. I always subtract 80mV from the voltage shown in the widget - which brings me rather close to the info I get when I run the script and compare the two readings. Do not expect absolute precision!

To all those who do not get "perfect" results on the first attempt: this is not a solution to the driver problem! I'm just telling you that there is a way to use Sim2K's "Battery Monitor" to get reliable info on battery charge on the tablet's homescreen. I cannot supply individual configuration advice, but I can assure you: if you start "playing around" with the settings (which cannot do any harm to your tablet!!!) you will certainly find the perfect values for the battery in your device. By the way, this is the reason why Sim2K created this app.
Quote: "VOLTAGE BASED (Read Me!): Voltage-based is provided for people with aftermarket/extended batteries that are not reporting true system values. Please be aware that the % value will fluctuate, this is something all lithium-ion batteries do." (Sim2k on Google Play)

I am satisfied with this workaround and have not experienced the problems discussed in this thread on my tablet again.

Have a nice weekend!

Edited by ralleweichs, 28 January 2013 - 02:35 AM.


#37 Tab_Gazer

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Posted 27 January 2013 - 09:42 PM

I tried Battery Monitor on F&L 717 w/ ICS 4.04 (elf 2) and it doesn't really work properly. It will update sometimes. On reboot, for example, or when adapter is plugged in. Got manual task killer on ignore, but didn't seem to kill it anyway. Also alerts didn't seem to work right.

Got the 100% stuck bug and already tried the counter reset once. Bit concerned about using it near 5% because I don't want to get stuck at 0% instead of 100. Also I am unclear on whether this is writing to a chip? Seems like that would have a limited life though might not ever get reached. The way this bug comes back never know.

Currently experimenting with Calibattery also. Has a similar approach.

Edited by Tab_Gazer, 27 January 2013 - 11:02 PM.


#38 Steve8x8

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Posted 28 January 2013 - 07:35 AM

May I just throw in an observation I made last weekend?
With the tablet discharged to about 70%, I connected the charger (Samsung USB, 700mA) and sent the Fire to sleep.
After several hours (30% of 5000mAh = 1500mAh, thus about 6 hours at 700mA should be more than enough even if the % display is non-linear), I disconnected the charger.
The battery of the Fire drained to 48% within a few hours (typical discharge rate was at ~100mA, or 2% per hour else).
Apparently it makes a difference whether the Fire is woken up and sent to sleep without a charger connected?

(Edit: running CM10.1 from mid-December)

Edited by Steve8x8, 28 January 2013 - 07:36 AM.


#39 entity1

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Posted 28 January 2013 - 09:18 AM

@rallewichs - Thanks for trying to help, it means alot. It looks like I still need to get a few more readings to really determine how long my battery life could be.

I guess this is the perks of buying a cheap tablet. My fire most of the time shuts itself down at 30% specially when I am running some apps plus wifi on plus the display brightness at half (the one with the half black half white shade circle thing). I went on a different route this time, I put the display brightness to the minimum and the main battery app was able to go down to 15% (double checked it with sim2k battery monitor, almost had the same numbers) which allowed me to get the notifications that the battery is nearly empty. This is also the first time that I was able to see red color inside the battery instead of the usual blue. Even if I opened wifi and some light apps (mail, facebook, etc) the tablet did not automatically turn itself off, which is curious because that is what it usually does at 30% and below. So I don't know, does the display brightness affect the tablet's reading of battery percentages or no?

#40 Billcnz

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Posted 28 January 2013 - 12:24 PM

May I just throw in an observation I made last weekend?
With the tablet discharged to about 70%, I connected the charger (Samsung USB, 700mA) and sent the Fire to sleep.
After several hours (30% of 5000mAh = 1500mAh, thus about 6 hours at 700mA should be more than enough even if the % display is non-linear), I disconnected the charger.
The battery of the Fire drained to 48% within a few hours (typical discharge rate was at ~100mA, or 2% per hour else).
Apparently it makes a difference whether the Fire is woken up and sent to sleep without a charger connected?

(Edit: running CM10.1 from mid-December)

Try to find a USB charger that is at least 1 amp, more mAh are used charging than discharging as some energy is wasted in heat. Also your charger may have over temp protection and shutdown if it gets too hot. I use a USB charger rated 2.1 amps so it only gets a little warm and can fully charge overnight.

Sent from my Novo 7 Flame running CM10.1 and Tapatalk HD