I have the very same problem with kernel 2.6.38.2 from kernel.org. Funnily the wrong percentage given by upower seems to be reported when the real one is > 50%.
$ upower --dump Device: /org/freedesktop/UPower/devices/line_power_AC native-path: /sys/devices/LNXSYSTM:00/device:00/PNP0A08:00/device:02/PNP0C09:00/ACPI0003:00/power_supply/AC power supply: yes updated: Thu May 26 11:17:43 2011 (320 seconds ago) has history: no has statistics: no line-power online: no Device: /org/freedesktop/UPower/devices/battery_BAT0 native-path: /sys/devices/LNXSYSTM:00/device:00/PNP0A08:00/device:02/PNP0C09:00/PNP0C0A:00/power_supply/BAT0 vendor: SANYO model: 42T4710 serial: 8352 power supply: yes updated: Thu May 26 11:22:48 2011 (15 seconds ago) has history: yes has statistics: yes battery present: yes rechargeable: yes state: discharging energy: 89.3217 Wh energy-empty: 0 Wh energy-full: 924.408 Wh energy-full-design: 103.496 Wh energy-rate: 24.2646 W voltage: 12.521 V time to empty: 3.7 hours percentage: 9.66258% capacity: 89.393% technology: lithium-ion History (charge): 1306401768 9.663 discharging 1306401738 9.691 discharging 1306401708 9.721 discharging 1306401678 9.750 discharging History (rate): 1306401770 24.265 discharging 1306401739 25.153 discharging 1306401710 24.742 discharging 1306401679 25.019 discharging Daemon: daemon-version: 0.9.10 can-suspend: yes can-hibernate yes on-battery: yes on-low-battery: yes lid-is-closed: no lid-is-present: yes is-docked: no $ acpi -V Battery 0: Discharging, 99%, 03:27:25 remaining Battery 0: design capacity 9324 mAh, last full capacity 8328 mAh = 89% Adapter 0: off-line Thermal 0: ok, 47.0 degrees C Thermal 0: trip point 0 switches to mode critical at temperature 98.0 degrees C Thermal 0: trip point 1 switches to mode passive at temperature 127.5 degrees C Cooling 0: LCD 4 of 15 Cooling 1: Processor 0 of 7 Cooling 2: Processor 0 of 7 Cooling 3: Processor 0 of 7 Cooling 4: Processor 0 of 7 Cooling 5: Processor 0 of 7 Cooling 6: Processor 0 of 7 Cooling 7: Processor 0 of 7 Cooling 8: Processor 0 of 7 $ cat /sys/class/power_supply/BAT0/charge_now 8088000 $ cat /sys/class/power_supply/BAT0/charge_full 8328000 -- To UNSUBSCRIBE, email to debian-bugs-dist-requ...@lists.debian.org with a subject of "unsubscribe". Trouble? Contact listmas...@lists.debian.org