Water electrolysis apparatus

A water electrolysis apparatus equipped with an anode separator and a cathode separator that are stacked with an electrolyte membrane sandwiched therebetween, an anode current collector interposed between the anode separator and the electrolyte membrane, and a cathode current collector interposed between the electrolyte membrane and the cathode separator, the water electrolysis apparatus being configured to generate hydrogen by electrolysis of water on a side of the cathode current collector, and further comprising:

• a hydrogen communication hole, which is formed to penetrate in a stacking direction through the anode separator, the electrolyte membrane, and the cathode separator, and allows the hydrogen to flow therethrough;
• and
• a communication hole body disposed between the anode current collector and the hydrogen communication hole;
• wherein,
• the communication hole body has an inside member facing toward the hydrogen communication hole, and an outside member disposed between the inside member and the anode current collector wherein the inside member is formed of a material which is gas impermeable or exhibits a smaller gas permeability than a gas permeability of a porous material;
• on a side of the outside member that faces toward the inside member, there are provided an accommodating chamber, which is interposed between the outside member and the inside member, and accommodates a seal member that seals the hydrogen communication hole and a side of the anode current collector, and an opposing surface that faces toward the inside member without the seal member being interposed therebetween;
• the inside member includes a through hole, which is formed in the inside member in a manner so that an opening on one end thereof faces toward the opposing surface, and an opening on another end thereof faces toward the hydrogen communication hole;
• the opening on the one end of the through hole is distanced from the accommodating chamber;
• and
• the accommodating chamber and the hydrogen communication hole communicate via the through hole and a gap between the opposing surface of the outside member and the inside member.