Find out how good/bad your battery is

[somline]

Since this thread has gone quite large I'll try to give you a short introduction of some interesting findings we made.

Please use Dr.Battery for all this and post everything regarding Dr.Battery in the support thread: Dr. Battery.

This thread now is for technical background findings and discussions about the secrets of the battery and the chip inside.

1. Get current condition of your battery.
To find out how much capacity your battery can hold you have to read two "files".
Use internalz (latest version), ssh or terminal and navigate to:
/sys/devices/w1_bus_master1/32-<something>

Easiest way (for linux "beginners") is internalz from jason.
If you don't know how to navigate in internalz puzzlegal is telling you here.
and read the two files:
getfull40
getage

getfull40 gives you the original capacity of your battery when it was new
getage gives you the percentage of the capacity your battery can hold now.

your capacity = getfull40 * getage / 100

The result of the formula could also be read in getcapacity (not exactly the same value and not true for huge batteries > 2000mAh)
From the manual:
"Batteries are typically considered worn-out when the full capacity reaches 80% of the rated capacity"

2. Your webOS device suddenly drops from 20% to 0% and shuts down or the device still runs 1-2 hours at 0%
This is the result of a "lying" battery.
In the battery is a chip with a logic and memory which is telling the phone how much "juice" is left in the battery.
If this memory is outdated the battery is thinking about still having power while it has not.
Batteries are loosing capacity over the used time. The logic in the battery chip is monitoring charge circles and adjusting its info.
Over the time and for some other reasons this info may not reflect the actual capacity.
The solution is to update the info within the battery chip (recalibrating).
To do so (and some linux knowledge) you can try my script here or adjust the "AGE" value by hand here.

3. You are using a (Seidio innocell) 1350mAh battery but you don't feel a difference to the original one
You should check the full40 value as described in point 1. It should around 1350.
Some (most?) (seidio) 1350mAh batteries are in fact 1150mAh. Last proof here.
In the thread you will find at least 8 members with a fake seidio.
If this does not convince you look at the customer ratings here or at amazon.
Here is how you should exchange your Seidio
Please go to this poll an share your results.

4. You've read don't use the batteries from a centro
I read that too.
The centro battery is communicating with the webOS kernel in the same way as the original one.
I don't see a reason to not use them.

5. You have a 2600mAh Battery but getcapcity is reading 600mAh
For some unknown reasons the values for getcapacity for the huge batteries may lie.
UPDATE: Seems to be an integer overflow in the getcapacity function of the kernel and to be only cosmetically with no impact on battery life.
But getfull40 and age should give you (almost) correct values.
And you get long battery life from them ;-)

6. Where does this info comes from?
I had problems with my battery and started searching the logfile /var/log/messages, finding infos in the filesystem /sys/devices and finally searched in the kernel sources.
Then we found out what chip is used inside the battery and got the manual of the chip.
With that information we played around with changing the info stored in the battery. As of today no palm or battery was harmed ;-)

Thanks to all members involved especially the once running dangerous commands in there devices only trusting my words ;-)

7. Member sipple31 has collected some helpful commands
Please remember that you are using this at your own risk. Patching the battery is dangerous. If you'r not sure what to do fell free to ask in this thread.
[CODE] -=( Battery cheat sheet )=-
**Use at your own risk**
Compiled by sipple31 for PreCentral.net
All of the work is thanks to Somline.
-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
## to disable the Pre's overcharge feature, add this line to powerd.conf:
/var/preferences/com.palm.power/powerd.conf
[battery]
disable_overcharge_check = true

## commands to set mAh to 2300:
2300:
cd /sys/devices/w1*/32-*
echo 0x6a1c > setreg
echo 0x6bc0 > setreg
reboot

## commands to set mAh to 2050:
2050:
cd /sys/devices/w1*/32-*
echo 0x6a19 > setreg
echo 0x6ba0 > setreg
reboot

## commands to set mAh to 1400:
1400:
cd /sys/devices/w1*/32-*
echo 0x6a11 > setreg
echo 0x6b80 > setreg
reboot[/CODE]
If my writing hurts your eyes it's probably because I'm not native english speaking.

[david7598]

mine is 1155.395

[beastlyschriefer]

mine reads 97.656625 does that mean my batt is <bad>?lol

[ProParkour]

getfull40- 1183.125, getage-100.00000.

I have a perfect battery. How delightful

[jyaden24]

getfull40:
1183.125
getage: x
88.28125
_______

104447.7539 / 100 = 1044.477539

????

[ProParkour]

Originally Posted by jyaden24

getfull40:
1183.125
getage: x
88.28125
_______

104447.7539 / 100 = 1044.477539

????

If the question marks mean that you have no clue what the number means than I can give you a nice guess to what it means.

A stock battery can hold up to 1150mAh. Your battery holds 1044mAh.

[R_E]

questions, where does the getfull40 number come from. number 2 can modifying these numbers cause you pre to attempt to charge the battery differently?

Also, just quick tip, you can access these files perfectly well with Internalz

[somline]

I think these numbers are coming direct from the battery itself. These are special files created by the kernel and readonly. I'm still investigating how you can reset/recalibrate this data.
If someone knows something about it, please post here.

EDIT: We know now, that this info is coming from the chip inside the battery (see post #101)

[R_E]

my getfull40 reads exactly 1150.0 while others seem to be different from stock numbers. This strikes me as weird because the ones posted above 1150 (1183.125) appears to be a number possible tested and calibrated to in the factory. Given how unlikely a tested capacity would turn out to be exactly 1150, one of the numbers is weird. either mine or the 1183.125 one. Can anyone else post their getfull40 numbers?

[jyaden24]

Originally Posted by beastlyschriefer

mine reads 97.656625 does that mean my batt is <bad>?lol

hahaha...thats made me laff after finding out what it means. That's a low number, I wonder if it is <bad>? :P

[Goingbended]

100%
1183.125
nice

[THL]

656,264 after 8 months. Who would have known... Glad, exchanging batteries is an easy task.

[somline]

Originally Posted by THL

656,264 after 8 months. Who would have known... Glad, exchanging batteries is an easy task.

Did we got bad batteries? Yours almost as bad as mine.
And agree, we don't have to send the phone to "apple" for an exchange

[GuyFromNam]

Originally Posted by beastlyschriefer

mine reads 97.656625 does that mean my batt is f'd?lol

Am I oversimplifying this or is getage simply the capacity percentage your battery is still capable of?

[somline]

No you'r not. It's the capacity percentage.
But I just wanted to show you the formula used by webOS.

[cdbillups]

GetAge = 98.43750
GetFull40 = 1150.00

98.43750 * 1150.00 / 100 = 1132.03125

[pastorrich1]

Intersting info. Somebody could probably make a fairly simple app or modification to an app like battery monitor to report this info easily.

Been using this Pre since Feb. and my capacity is at 90%.

All lithium ion batteries have "X" number of charge cycles. One full cycle is full depletion to full charge. Since lithium ion batteries don't establish a memory cycle, four separate 25% charges equals one full cycle (or any combination adding up to 100%). So as you run through the charge cycles the battery loses capacity. It is similar to filling a cup with concrete slowly over time. The portion filled with concrete is no longer availabe for holding liquid. This happens until there is no more capacity in the battery to hold a charge.

The rate of capacity loss is not a fixed rate. Many factors contribute, but temperature is likely the greatest. Keeping your battery in the 40-70% charged state and slightly above freezing temperatures will give it the longest life, keeping it at 100% charged and at room temperature or hotter will give it the shortest life.

You can learn quite a bit about lithium ion batteries at batteryuniversity.com.

[Joescan09]

Mine is 1081

[Workerb33]

why isn't this included in the Battery Gauge app already?

[GuyFromNam]

Wow, just popped in my spare that I got off a broken screen Pre I once bought on ebay:
100.00000