View Full Version : asus eeepc x101 owners cat /proc/acpi/battery/BAT0

January 23rd, 2013, 12:23 AM
Hopefully not at the wrong place I m looking for some informations about laptop battery of an asus x101 model e.g. a31-x101. that is a 3 cell one.

Mine has given up recently just 30 minutes left :-( after 9 months powerusing
The prices for this type of batt ranges from ~40 - 90 Eur. Thats a lot I thougt
so why not hacking the batt.
I checked cat /proc/acpi/battery/BAT0/info and saw just some 800 mA last full capacity.
So I decided to open the plastic and check the malicious cell. It was a hard work to open the case and keep the batt working. Then I connected a cell-logger with some soldering and found the middle cell more than 400mV difference to the right one. Without load!.
The cell-logger told me the laptop-charging algorithm is not balancing the cells.
So i connected the removed batt to a separate lipo balancer charger.
Still all cells left soldered in the case a retry after balancing told 1670mA last full capacity that was feeled too optimistic due to just some minutes more now without adapter.

Finaly I changed the cells with some i know are good . And bricked the batt. :((

So far still some information is present but no supply, and no charging.
The voltage reading is exactly the one the cell-logger reports.
But the serial number is missing now, and the cycles is set to 0

The net told me lots of stuff about the batt controllers possibilities, but so far i have no idea which one is really inside nor how to make the reset.

May someone post a working batterys info or more if you can generate somehow.

My goal would be to bring the "repaired" batt back to life and then donate half the price of a new batt bucks to a human organization.

here what is left

>cat /proc/acpi/battery/BAT0/info
present: yes
design capacity: 2600 mAh
last full capacity: 1670 mAh
battery technology: rechargeable
design voltage: 10800 mV
design capacity warning: 10 mAh
design capacity low: 5 mAh
cycle count: 0
capacity granularity 1: 26 mAh
capacity granularity 2: 26 mAh
model number: X101
serial number:
battery type: LION
OEM info: ASUS

>cat /proc/acpi/battery/BAT0/state
present: yes
capacity state: ok
charging state: charging
present rate: 0 mA
remaining capacity: 1571 mAh
present voltage: 12192 mV

>acpi -b
Battery 0: Charging, 94%, charging at zero rate - will never fully charge.

tools used and opened cellpack

Cell-logger attached shows number 2 has a low voltage

Here the batt is discharging with the logger attached

Finally this is what is left by now, nice view no charging no discharging in the netbook