Battery monitor's alarm doesn't work with eeepc.
I'm not an expert but read something about problems with mintes remaining that should be fixed using percentages instead.

This little script works great:

if ! grep -q on-line /proc/acpi/ac_adapter/AC0/state ; then
    BAT_DIR=/proc/acpi/battery/BAT0
    FULL_BAT=`grep 'last full capacity' ${BAT_DIR}/info | awk '{ print $4 }'`
    CUR_BAT=`grep 'remaining capacity' ${BAT_DIR}/state | awk '{ print $3 }'`
    AVG=`expr $(expr ${CUR_BAT} \* 100) / ${FULL_BAT}`

    if [ "$AVG" -le "20" ]; then
        echo "Battery warning... "$AVG &
    fi
fi

I'll try to guess how to addapt something similar to lxde's battery monitor.

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