CELL ABNORMALITY DETECTING DEVICE FOR FUEL BATTERY, FUEL BATTERY DEVICE, AND CELL ABNORMALITY DETECTING METHOD FOR FUEL BATTERY

摘要

PROBLEM TO BE SOLVED: To accurately detect abnormality of a fuel battery cell even when polarity inversion states of fuel battery cells occur at the same time in plural cell groups.SOLUTION: A cell abnormality detecting device 50 for a fuel battery has: an alternating current applying unit 52 for applying alternating current to a cell group 18; a measuring unit 54 for measuring impedance of the cell group 18 when the alternating current is applied; a calculating unit 56 for calculating the upper limit value of cell impedance on the basis of cell group impedance measured by the measuring unit 54, an impedance increasing rate at a cell in which a cell abnormality occurs, cell impedance per cell under normal potential, a predetermined number of abnormality occurring cells and the number of cells constituting the cell group 18; and a determining unit 58 for comparing the upper limit value of the cell impedance and the average cell impedance obtained by dividing the cell group impedance by the cell number to determine occurrence or non-occurrence of abnormality of the fuel battery cell 24.