Patent ID: 7323090

Claim:
A bipolar, zero-gap type electrolytic cell for use in a filter press type electrolyzer having a plurality of bipolar electrolytic cells and a plurality of anodic ion exchange membranes each arranged between adjacent bipolar electrolytic cells, comprising: an anode chamber; an anode provided in the anode chamber, said anode being formed of an anode base material comprising one of a titanium expanded metal and a titanium wire netting with an open area percentage of 25% to 75%, said anode, after being applied with a catalyst on the anode base material, having a maximum height difference of 5 μm to 50 μm between irregularities on a surface thereof and a thickness of 0.7 mm to 2.0 mm; a cathode chamber arranged back to back with the anode chamber; and a cathode having at least two layers stacked in the cathode chamber, said layers including a conductive cushion mat layer and a layer of a hydrogen generating cathode, said hydrogen generating cathode layer being adjacent to the cushion mat layer and arranged in an area for contact with the anodic ion exchange membrane.