There is no difference in the battery performance when using this computer. The designed battery capacity is shown less, however, the discharge period is not affected.
During the system startup with the AC adapter plugged, if you set and remove the battery, the battery capacity indicates 17.20Wh. However, if the PC is restarted, it indicates 15.50Wh.
Page 155 of the Instruction Manual [Battery Pack] -> [Output voltage and capacity] must be corrected as follows:
Wrong: 11.1V, 550mAh
Correct: 11.1V, 1550mAh