[WORKAROUND][SamPWND] Charge to 100% Snapdragon Root

[nm1557]

I was able to find a workaround for the battery percentage:

1. FIRST Get your battery capacity!!!
$ adb shell cat /sys/class/power_supply/battery/batt_capacity_max
800

2. Calculate your 100%
800 * 1.2 = 960

3a. Charge battery fully (UI will say 80%):
Use your new 100% value in place of my 960!!
adb shell
$ su
# echo 960 > /sys/class/power_supply/battery/batt_capacity_max

3b. To revert back (and see actual %):
put your old value in place of my 800 here
adb shell
$ su
# echo 800 > /sys/class/power_supply/battery/batt_capacity_max

Warning:

1. This is not persistent across reboots (but could be implemented as such)
2. This does not change the fact that your battery meter will say 80%
3. This confuses your phone into thinking the 80% limit is higher than it actually is
4. This could be harmful to your battery life, battery condition, and battery operation
5. The Control Chip on the battery itself should prevent any unnecessary charging from occurring
6. I'm just a guy on the internet, don't mess with your phone unless your are willing to pay for any mistakes.

How this works:

1. The Kernel reads the battery percentage from /sys/class/power_supply/battery/capacity
2. We make the maximum battery capacity increase by 20% /sys/class/power_supply/battery/batt_capacity_max (the commands above)
3. Kernel reads the battery percentage from /sys/class/power_supply/battery/capacity again and its now 20% lower because of capacity calculations (percentage = used capacity / batt_capacity_max)
4. Kernel lets the charging continue to 80% which is in actuality 100%

FAQ

1. Does this work?
   
   Yes this works. The explanation is above. Succinctly, these commands trick your kernel into thinking the 80% limit is at 100% of the battery.​
2. Shouldn't we be adding 25% to reach 100% of the battery?
   
   While this is correct, I tested a few percentages and noted that 20% increase will reach 99% battery on my phone. This does not mean it will for everyone. PLEASE BE COGNIZANT OF OVERCHARGING​
3. This isn't working for me, why do the values change?
   
   You must be a superuser in the terminal for these commands to stick. They do not stick across reboots.​
4. This still doesn't work, wah wah wah. I wan't 100%...
   
   I am trying to help the community. If you don't want help you can keep the 80% charge. Multiple people have said it works. If you don't want to try it don't. Blindly saying it doesn't work is only poisoning the well.​

Video Guide:

Setting Battery Maximum Past 80%
https://youtu.be/dEdmIDEKYtA

Setting Battery Maximum Back to Original
https://youtu.be/TDirEoSsSkk

 

[Rally517]

But does it actually go to 100?

 

[nm1557]

If you do step 3b after you charge to 80% it will change to say 100%.

Steps 1,2,3a will bring you to 100% charge physically; almost as if the battery meter was designed to go 0-80

Note: this charges to your battery maximum (regardless of what percentage it says)

 

[fever308]

If you do step 3b after you charge to 80% it will change to say 100%.

Steps 1,2,3a will bring you to 100% charge physically; almost as if the battery meter was designed to go 0-80

Note: this charges to your battery maximum (regardless of what percentage it says)

interesting, anyway to keep it persistent?

 

[peachpuff]

2. Calculate your 100%
800 * 1.2 = 960

That's 96%, multiply it by 25 to get 100%.
Hmm the original file says 948 though, strange.

 

[nm1557]

That's 96%, multiply it by 25 to get 100%.
Hmm the original file says 948 though, strange.

Yours may be different. It's based off your battery stats. And it should only be 20% increase.

 

[nm1557]

interesting, anyway to keep it persistent?

Write a shell script that runs on start.

This is a verbose way to do this, I am looking into a better way to get around the kernel.

 

[peachpuff]

And it should only be 20% increase.

Yes but you're multiplying 20% of 80 which is incorrect, that only gives you 96% not 100%.
If you subtract 20% from 1000 you get 800, but when you add 20% to 800 its 960, get it?

 

[nm1557]

Yes but you're multiplying 20% of 80 which is incorrect, that only gives you 96% not 100%.
If you subtract 20% from 1000 you get 800, but when you add 20% to 800 its 960, get it?

That's the thing, The 800 value has nothing to do with percentage. It's variable across devices and its coincidence thats its 800.

 

[Rally517]

So is it really 100 or just the image of it

 

[nm1557]

So is it really 100 or just the image of it

It really is 100%.

 

[Rally517]

Hmmm. Have you battery life changed in any way? Just got me excited

 

[TyPhyter]

i bit the bullet on this and went for it. everything seems to be fine so far. my max_batt_capacity value was 885, so 100% would be 1062, however, i backed it off to 1000, just to be safe. will update after tomorrow.

 

[MrBriggs]

If A is the number we want the phone to charge the battery to, and the phone stops charging at 80% of A, the number we need to set A to is A * 1.25 , not A * 1.2

So, if the original number is 800, we need to set it to 1000, since the phone will calculate 80% of 1000 to allow it to be charged until 800.

Does that make sense?

 

[tommyg562000]

So you are effectively increasing the battery capacity of an s8 by 600 mah and s8+ by 700 mah? Am I understanding this thread correctly? If so this seems like a huge problem waiting to happen.

 

[TyPhyter]

So you are effectively increasing the battery capacity of an s8 by 600 mah and s8+ by 700 mah? Am I understanding this thread correctly? If so this seems like a huge problem waiting to happen.

no, this is a work around after using the SAMpwned root method, which caps the battery life at 80% of max.

 

[progro420]

Lol I have a feeling we are gonna see some batteries exploding again, lol

Sent from my SM-G955U using Tapatalk

 

[tvm2487]

I'm still on the stock rom and unrooted and the stock valve in the batt_capacity_max file is 990

 

[elliwigy]

great find! i figured it had something to do with that file but wasnt sure how it was calculated as mine says 1000 but others was different lol..

but our idea was if this was in fact the case that you create an init.d script that runs on each boot that will automagically correct it each time you reboot the phone

---------- Post added at 07:35 AM ---------- Previous post was at 07:34 AM ----------

to add, this is also why we releaeed it as is, we figured someone in the community would figure it out!

thanks again!

---------- Post added at 08:26 AM ---------- Previous post was at 07:35 AM ----------

actually, changing that file instantly changes back to its original setting for me

 

[MrBriggs]

One thing that I didn't get.

Okay, the phone will think the maximum is 1000 and will try to charge the battery up to 800, which is the real target. Great.

The screenshot, though, shows the indicator on the notification bar close to 100%, in the rooted phone.

So, the routine that checks the phone charge and limits it to 80% is independent from the check embedded on the indicator charge, right? Otherwise the indicator would never reach 100% even on the rooted phone, and even though the battery was actually 100% charged.