What is the meaning of energy_full and energy_full_design?

asked 2014-06-16 15:18:21 +0200

rcasta74
11 ●1 ●2 ●3

After last update [1.0.7.16] I started to experiencing an issue like the one described in https://together.jolla.com/question/40196/immediate-battery-level-drop-from-more-than-half-charged-to-empty/

I wanted to check the battery level from console and I found strange values (with battery fully charged):

[nemo@Jolla ~]$ cat /sys/class/power_supply/battery/status
Full
[nemo@Jolla ~]$ cat /sys/class/power_supply/battery/energy_full_design 
7980000
[nemo@Jolla ~]$ cat /sys/class/power_supply/battery/energy_full
7225320
[nemo@Jolla ~]$ cat /sys/class/power_supply/battery/energy_now 
7980000

I was thinking that energy_full_design is the max level of battery when is out of factory and energy_full the real max level that decrease with the life of the battery itself, but in this case I cannot understand why the value of energy_now is so higher than energy_full and still identical to energy_full_design after 6 month of use.

Moreover using upower command to get information about battery, the output is as follow:

[nemo@Jolla ~]$ upower -i /org/freedesktop/UPower/devices/battery_battery
  native-path:          battery
  power supply:         yes
  updated:              Mon 16 Jun 2014 02:07:44 PM CEST (3 seconds ago)
  has history:          yes
  has statistics:       yes
  battery
    present:             yes
    rechargeable:        yes
    state:               fully-charged
    energy:              7.98 Wh
    energy-empty:        0 Wh
    energy-full:         7.98 Wh
    energy-full-design:  7.98 Wh
    energy-rate:         0.496531 W
    voltage:             4.3072 V
    percentage:          100%
    temperature:         30.7 degrees C
    capacity:            90.4857%
    technology:          lithium-ion

energy-full value was 7.22076 Wh when it started charging

Maybe are the values reported under /sys/class/power_supply/battery/ wrong? Or am I missing some information to correctly read them?