Patent ID: 8715474

Claim:
A gas sensor element comprising: a solid electrolyte layer having proton conductivity; a first cell; and a second cell, wherein: the solid electrolyte layer having proton conductivity is commonly used by the first cell and the second cell, the first cell comprises a first anode and a first cathode, the first anode is formed on one surface of the solid electrolyte layer and is exposed to a target detection gas containing hydrogen atoms, the first cathode is formed on the other surface of the solid electrolyte layer, and the second cell comprises a second anode, a second cathode, and a shield layer impermeable to gas, the second anode is formed on one surface of the solid electrolyte layer, the second cathode is formed on the other surface of the solid electrolyte layer, and the second anode of the second cell is covered with the shield layer, the gas sensor element further comprises a diffusion layer and a target detection gas chamber, the target detection gas chamber communicates with an external space through the diffusion layer, the target detection gas in the external space is introduced into the inside of the target detection gas chamber through the diffusion layer, at least the first anode of the first cell is arranged in the inside of the target detection gas chamber so that the first anode of the first cell is exposed to the target detection gas, the gas sensor element further comprises a spacer and a heater layer, the spacer is formed between the solid electrolyte and the heater layer so that the spacer, the diffusion layer, the solid electrolyte and the heater layer form the target detection gas chamber, and wherein the second anode is covered with a part of the spacer which is used as the shield layer.