Method and apparatus for recovering performance of fuel cell stack

Abstract

A method for recovering performance of a fuel cell stack includes 1) a first pulse operation process including i) generating a hydrogen pumping reaction in a cathode by applying a current to the cathode after a supply of air to the cathode stops and ii) maintaining an OCV (open circuit voltage) by again supplying air to the cathode after the hydrogen pumping is performed, 2) a pole substitution process of substituting a pole of the fuel cell stack, and 3) a second pulse operation process including iii) generating the hydrogen pumping reaction in the cathode after the pole substitution, and iv) maintaining the CCV (open circuit voltage) by supplying air to the cathode after the pole substitution after the hydrogen pumping is performed.

What is claimed is: 
     
         1 . An apparatus for recovering performance of a fuel cell stack, comprising:
 a fuel cell stack having a solid polymer electrolyte membrane between an anode and a cathode;   a supply gas flow change mechanism for changing a flow of hydrogen and air supplied to the fuel cell stack;   a current flow change mechanism for changing a pole of the fuel cell stack;   a gas cut off mechanism for cutting off a flow of air to the cathode.   
     
     
         2 . The apparatus according to  claim 1 , wherein the supply gas flow change mechanism is a 3-way valve. 
     
     
         3 . The apparatus according to  claim 1 , wherein the current flow change mechanism is a contact type relay. 
     
     
         4 . The apparatus according to  claim 1 , wherein the supply gas flow change mechanism and the current flow change mechanism are automatically operated while interlocked with each other.