[ltp] battery balancing on Ivy Bridge & later

Tamas Papp linux-thinkpad@linux-thinkpad.org
Tue, 25 Feb 2014 11:07:46 +0100


Hi Peter,

Since you are here to comment on software issues, I would like to ask
about battery balancing, ie the ability to discharge two batteries (main
and ultrabay) in a more or less balanced fashion on Ivy Bridge and later
laptops.

As far as I know, this used to work before Ivy Bridge [1], but the ACPI
functionality is not available on my T430s any more (see [2]).
Consequently, my T430s discharges the ultrabay battery first, down to 0%
(!), and only then start using the main battery. I believe that this is
bad for the ultrabay battery in the long run.

A solution would be very nice --- I am sure that if the developer of eg
[3] got a bit of help from the Lenovo SW people this could be
incorporated very easily.

Best,

Tamas

[1] www.thinkwiki.org/wiki/Tp_smapi
[2] https://github.com/teleshoes/tpacpi-bat/issues/29
[3] https://github.com/teleshoes/tpacpi-bat