| 摘要 |
PROBLEM TO BE SOLVED: To provide a battery pack system which safely and surely performs a secondary battery life end decision at low cost. SOLUTION: A unit cell 111 for comparison determination of which, internal resistance always rises quickly, and deterioration always starts at first compared with other cells, is prepared. The internal resistance of the unit cell for comparison determination is monitored for every cell, and the internal resistance of other cells is monitored for every block for detecting voltage of the like, and the cell life end decision is carried out by comparing both internal resistances. |
