Calibrating the HP Laptop Battery This document pertains to HP Notebook PCs with Windows 7 and Vista. Calibrating the laptop battery Calibrating the battery means recharging the battery to its maximum capacity and resetting the battery gauge to display the level of charge accurately. The Windows system tray battery meter may not correctly display the battery charge level when a notebook is new or has not been used for a long period of time. If the battery gauge becomes inaccurate, use one of the methods below to calibrate the battery gauge reading. Calibrate the battery while PC is in use A calibration cycle requires that the battery be completely charged and then completely discharged. During the calibration cycle, the power management properties must be disabled to allow the battery to completely discharge.