BATTERY STATE DETECTION METHOD AND DEVICE, AND OPERATION EXPRESSION DERIVATION METHOD

PROBLEM TO BE SOLVED: To provide a battery state detection device or the like capable of estimating accurately a physical quantity such as a dischargeable capacity measured until the voltage of a secondary battery is lowered to a required voltage for an electric load. SOLUTION: This battery state detection device 100 for detecting the state of the secondary battery 200 for feeding an external apparatus 300 includes a memory 60 for storing characteristic data for specifying a discharge characteristic of the secondary battery 200 showing a discharge state until the voltage of the secondary battery 200 is lowered to a voltage value necessary for the external apparatus 300, and an operation processing part 50 for estimating the dischargeable capacity or a dischargeable time of the secondary battery 200 based on the characteristic data stored in the memory 60. COPYRIGHT: (C)2009,JPO&INPIT