Patent ID: 9444112
Filing Date: 2016-09-13
CPC Classification: H01M,Y02E

Claim Text:
1. A fuel cell monitoring device which monitors a fuel cell comprising one or more unit cells capable of performing electrochemical reaction of reaction gas comprised of fuel gas and oxidizing gas to generate electric power when receiving the reaction gas, the fuel cell monitoring device comprising: a current detection section configured to detect an output current of the fuel cell; a voltage detection section configured to detect an output voltage of each of the unit cells; a signal superposing section configured to superimpose a signal of a different frequency on an output signal of the fuel cell; an impedance calculation section configured to calculate and map an impedance at every frequency on a basis of the output current detected by the current detection section and the output voltage detected by the voltage detection section when the signal superposing section superimposes the signal at every frequency on the output signal of the fuel cell; and a diffusion resistance detection section configured to calculate and map a first diffusion resistance showing diffusion characteristics which vary due to a flooding in the inside of the fuel cell, and the diffusion resistance detection section comprising: the fuel cell monitoring device detects an excess state of water content in a fuel cell on the basis of the calculated first diffusion resistance, such that the fuel cell monitoring device operates in an optimum water content range.