1. I was wondering how to check the current charged percentage of battery on my Lenovo T400?

  2. I forgot which program I used to control the battery to stop charging at 60% and start charging at 40%.

    Now I want to adjust the thresholds. So I wonder how to do that?


1: In general, the directory /proc/acpi/battery/ should have a host of information about your battery. So cat /proc/acpi/battery/info should bring up original manufacturing information and cat /proc/acpi/battery/state should bring up current information, including the charging status.

More specifically, since you have a Lenovo, I think these commands might work as well (maybe these will work and the above ones won't):

cat /sys/devices/platform/smapi/BAT0/state
cat /sys/devices/platform/smapi/BAT0/remaining_percent
cat /sys/devices/platform/smapi/BAT0/remaining_running_time
cat /sys/devices/platform/smapi/BAT0/remaining_charging_time
cat /sys/devices/platform/smapi/BAT0/remaining_capacity

2: I think this is what you're after:

Set starting charge at 40%:

echo 40 > /sys/devices/platform/smapi/BAT0/start_charge_thresh

Set stopping charge at 70%:

echo 70 > /sys/devices/platform/smapi/BAT0/stop_charge_thresh

Display charging thresholds:

cat /sys/devices/platform/smapi/BAT0/*_charge_thresh

There's a whole host more features, commands and information here.

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  • Thanks! My system does not have directory smapi under /sys/devices/platform/smapi. It does not have the files supposed to be under smapi, such as remaining_percent, remaining_charging_time, start_charge_thresh. – Tim Aug 27 '11 at 2:40
  • And I take it you don't have /proc/acpi/battery as well? – Kris Harper Aug 27 '11 at 3:45
  • I have /proc/acpi/battery/BAT0/ . But I cannot find in the three files alarm, info and state the information about how much percentage has been charged. – Tim Aug 27 '11 at 3:49
  • Is there anything in the /BAT0 directory? – Kris Harper Aug 27 '11 at 4:26
  • There are three files alarm, info and state. – Tim Aug 27 '11 at 11:36

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