| 摘要 |
PROBLEM TO BE SOLVED: To correctly detect a parameter for detecting a battery remaining capacity in a battery pack in which secondary batteries are housed. SOLUTION: The battery pack is equipped with a charge discharge frequency measuring part 131 measuring charge discharge frequencies based on integrated value of charging current to the secondary battery and a deterioration ratio output part 132 calculating deterioration ratio showing a degree of deterioration of the secondary batteries based on the charge discharge frequency measured with the charge discharge frequency measuring part 131. The charge discharge frequency measuring part 131, for example, repeatedly integrates detected values of charge discharge to a prescribed threshold value and counts up the charge discharge frequencies every time when the integrated values reach the threshold value. Thereby, even when charge and discharge are repeated little by little in a relatively narrow voltage range, the charge discharge frequencies can correctly be counted, and calculating accuracy of the deterioration ratio is enhanced. COPYRIGHT: (C)2007,JPO&INPIT |
