Nissan Motor Company Limited

Nobuo Matsuba

Kazuo Sato

Takahiro Fujii

Kazuo Saito

Masashi Sato

Ryoichi Shimoi

Susumu Maeshima

Hitoshi Igarashi

Kenji Yonekura

Susumu Maejima

A fuel cell system has a plurality of fuel cells stacked in one or more groups of fuel cells. Each fuel cell includes a fuel electrode supplied with fuel gas at a fuel gas supply pressure, an oxidizing electrode supplied with oxidizing gas at an oxidizing gas supply pressure, and an electrolyte membrane disposed between the fuel electrode and the oxidizing electrode. A pressure-difference control unit generates a pressure difference across the membrane such that the fuel gas supply pressure is greater than the oxidizing gas supply pressure in each fuel cell, a cell-voltage measuring device measures a cell voltage for each fuel cell or each group of fuel cells in the fuel cell stack, and a leakage determination unit determines the presence or absence of a leaking cell based on the behavior of the cell voltage of each fuel cell while the pressure difference is increased with time.

Fuel cell system

Growing community of inventors

Ebina, Japan

Nobuo Matsuba