Fuel cell system

A fuel cell system comprising:

• a fuel cell,
• an oxidant gas supplier configured to supply oxygen-containing oxidant gas to a cathode of the fuel cell,
• a fuel gas supplier configured to supply hydrogen-containing fuel gas to an anode of the fuel cell,
• an oxygen partial pressure estimator configured to estimate an oxygen partial pressure of the cathode of the fuel cell,
• a hydrogen partial pressure estimator configured to estimate a hydrogen partial pressure of the anode of the fuel cell, and
• a controller,
• wherein the fuel cell includes one or more unit fuel cells;
• wherein the one or more unit fuel cells include a membrane electrode assembly;
• wherein the membrane electrode assembly includes an anode including an anode catalyst layer, an electrolyte membrane, and a cathode including a cathode catalyst layer in this order;
• wherein the electrolyte membrane includes a catalyst dispersion portion in the electrolyte membrane, which is arranged in parallel with the anode catalyst layer and the cathode catalyst layer in a layered manner;
• wherein the catalyst dispersion portion contains a catalyst;
• wherein the controller calculates a target hydrogen partial pressure by the following equation (1):
• Target hydrogen partial pressure=[2×Oxygen permeation coefficient in electrolyte membrane thickness direction×{Distance from the anode catalyst layer to the catalyst dispersion portion÷(Electrolyte membrane thickness−Distance from the anode catalyst layer to the catalyst dispersion portion)}×Oxygen partial pressure]÷Hydrogen permeation coefficient in the electrolyte membrane thickness direction;
• Equation (1):
• and
• wherein the controller controls the hydrogen partial pressure of the anode to the target hydrogen partial pressure.