100% battery show as 71%

I have two potent batteries in my laptop

The power settings presents it like this Battery 1: 100%, Battery 2: 100% Total Battery 71%.

How should I understand these percentages? I didn't crop just to show the gs app shows the same percentage.

upower reports the following on Battery 1

 native-path: BAT0 vendor: SANYO model: 00HW022 serial: 2206 power supply: yes updated: sat 22 jan 2022 12:44:14 (34 seconds ago) has history: yes has statistics: yes battery present: yes rechargeable: yes state: fully-charged warning-level: none energy: 18,89 Wh energy-empty: 0 Wh energy-full: 25,83 Wh energy-full-design: 23,51 Wh energy-rate: 2,53 W voltage: 12,721 V percentage: 99% capacity: 100% technology: lithium-polymer icon-name: 'battery-full-charged-symbolic' History (charge): 1642851854 99,000 fully-charged

On battery 2

 native-path: BAT1 vendor: SMP model: 01AV406 serial: 1111 power supply: yes updated: lör 22 jan 2022 12:50:14 (12 seconds ago) has history: yes has statistics: yes battery present: yes rechargeable: yes state: fully-charged warning-level: none energy: 14,76 Wh energy-empty: 0 Wh energy-full: 21,18 Wh energy-full-design: 26,06 Wh energy-rate: 1,092 W voltage: 12,637 V percentage: 100% capacity: 68,8795% technology: lithium-polymer icon-name: 'battery-full-charged-symbolic'

It does seem to be related to battery wear, energy/energy-full is 73% on BAT0, 70% on BAT1.

1 Answer

As @matigo suspected it is showing the percentage of the design charge capacity specification provided by the battery.

I find this odd because when my battery is at (now) 70% I imagine I should be able to charge it back to 100%.