Re: how to control battery charge level on a laptop

[RVP <rvp%SDF.ORG@localhost>]

On Wed, 22 Oct 2025, Henry wrote:

>  1) design capacity is said to be 5.376Ah, but written directly on the
> battery is 7.7V, 41Wh (=~5.324Ah) and nominal 5350mAh.  While small, the
> battery is being overcharged to 5.376Ah (101%).  Is there a way to
> correct the design capacity to 5.324Ah, and force the machine to keep
> the charge no higher than 5.324Ah?

You can't change the design capacity. `last full cap' will decrease as the
battery ages.

>  2) the CritMax and WarnMax entries are blank.  Is there a way to
> inform the machine of these parameters, and issue a warning and stop
> charging the machine until the issue is resolved?

You can, at least, be informed when your thresholds (low, high) are reached.
See: https://www.unitedbsd.com/d/401-help-me-understand-a-thing-or-two/30
and envsys.conf(5).

>  3) the WarnMin and CritMin for charge are 12.091% and 7.068%.  What
> actions are taken, if any, when these levels are reached?

Messages are logged to syslog. See: /etc/powerd/scripts/sensor_battery

-RVP