Re2: [ltp] battery balancing on Ivy Bridge laptops

Tamas Papp linux-thinkpad@linux-thinkpad.org
Sun, 30 Jun 2013 20:13:50 +0200


On Wed, May 08 2013, pseelig@rumbero.es wrote:

> On 05/08/2013 03:17 PM, Tamas Papp wrote:
>> Now the only thing I need is some way to achieve battery balancing, even
>> manually.
>
> Judging by the short functionality summary shown on the entry page at
> https://github.com/teleshoes/tpacpi-bat, i guess this could be achieved
> without bothering with tlp:
>
> <inhibit>    1 for inhibit charge, 0 for stop inhibiting charge
> <discharge>  1 for force discharge, 0 for stop forcing discharge
> <acbreak>    1 for stop forcing when AC is detached, 0 for do not
>
> I was about to include a battery switch feature based on tpacpi-bat in
> the ultrabay-battery script, but having a closer look at tpacpi-bat
> exposed this unfortunate drawback:
>
> # Limitations/Known Issues:
> # 1) you cant force discharge on battery, so balancing is still impossible
>
> So i fear we are out of luck here, unless someone verifies that it
> doesn't apply once a secondary UltraBay battery is involved. Could you
> try that manually, Tamas?

Hi Paul (sorry for the late reply),

I just checked with the latest tpacpi-bat, and the UltraBay does not
help, picking which battery to discharge is still impossible.

For now, I ended up implementing a small script that gets run by cron
and displays a message when the ultrabay battery goes below 30%, so I
can remove it manually.  That appears to be the only way to prevent it
from discharging first to some insanely low level (near 3-5%).

Best,

Tamas