PORTABLE INFORMATION PROCESSOR, AND CHARGING DEVICE AND METHOD

摘要

PROBLEM TO BE SOLVED: To make increase of charged capacity in portable use compatible with prevention of deterioration of a battery used on a desk. SOLUTION: When a charging controller 24 starts charging in a built-in battery 10 by connecting external power supply by an AC adapter 14, charged capacity of the built-in battery 10 is set to the first charged voltage in which the charged capacity to be charged is maximized. When using on a desk in which the AC adapter 14 is in the connection state at all times, when the built-in battery 10 detects drop of the capacity by self discharging to start charging, the second charging voltage is set lower than that of the first charging voltage so as to prevent deterioration of the battery.