Water electrolysis system

Abstract

A water electrolysis system having: a membrane-electrode assembly; a first separator in contact with a hydrogen electrode of the membrane-electrode assembly; a hydrogen flow passage provided between the first separator and the hydrogen electrode; a second separator in contact with an oxygen electrode of the membrane-electrode assembly; an oxygen flow passage provided between the second separator and the oxygen electrode; and a cooling device that cools the hydrogen electrode such that a temperature of the hydrogen electrode becomes lower than a temperature of the oxygen electrode.

What is claimed is: 
     
         1 . A water electrolysis system comprising:
 a membrane-electrode assembly;
 a first separator in contact with a hydrogen electrode of the membrane-electrode assembly; 
 a hydrogen flow passage provided between the first separator and the hydrogen electrode; 
 a second separator in contact with an oxygen electrode of the membrane-electrode assembly; 
 an oxygen flow passage provided between the second separator and the oxygen electrode; and 
 a cooling device that cools the hydrogen electrode such that a temperature of the hydrogen electrode becomes lower than a temperature of the oxygen electrode. 
   
     
     
         2 . The water electrolysis system according to  claim 1 , further comprising a water supply device that supplies water to the oxygen flow passage, wherein the cooling device supplies a cooling liquid at a lower temperature than the water in the oxygen flow passage to the hydrogen flow passage. 
     
     
         3 . The water electrolysis system according to  claim 1 , further comprising a frame body made of resin that is sandwiched between the first separator and the second separator and provided along a peripheral edge of the membrane-electrode assembly, wherein the cooling device cools a joint portion between the membrane-electrode assembly and the frame body.