Electric double layer capacitor and method of forming the same

Abstract

A unitary-formed electrode structure serving as both a collector and a polarization electrode includes an electrically conductive base serving as the collector, and a polarization electrode that includes a multiplicity of separate polarization particles dispersed throughout the base and exposed in at least a part of a surface of the base.

What is claimed is:  
     
         1 . A method of forming a unitary-formed electrode structure serving as both a collector and a polarization electrode, said method comprising the single step of: 
 mixing a polarization electrode material into at least a part of a surface region of a base material having an electrical conductivity, so that at least said polarization electrode material is partially shown on said surface region of said base material.    
     
     
         2 . The method as claimed in  claim 1 , further comprising the single step of: 
 removing a surface part of said base material to increase an area of said shown polarization electrode material from said surface region of said base material.    
     
     
         3 . The method as claimed in  claim 2 , wherein said surface part of said base material is removed by a plasma irradiation.  
     
     
         4 . The method as claimed in  claim 2 , wherein said surface part of said base material is removed by a heat treatment.  
     
     
         5 . The method as claimed in  claim 2 , wherein said surface part of said base material is removed by an ozone irradiation.  
     
     
         6 . The method as claimed in  claim 2 , wherein said surface part of said base material is removed by making said surface part of said base material into contact with an organic solvent.  
     
     
         7 . The method as claimed in  claim 2 , wherein said base material is sheet-shaped and said surface part to be removed is one side of said sheet.  
     
     
         8 . A method of forming an electric double layer capacitor, said method comprising the steps of: 
 mixing a polarization electrode material into at least a part of a surface region of a base material having an electrical conductivity for serving as said collector, so that at least said polarization electrode material is partially shown on said surface region of said base material;    removing a surface part of said base material to increase an area of said shown polarization electrode material from said surface region of said base material, thereby forming at least a pair of unitary-formed electrode structures serving as both a collector and a polarization electrode;    permeating an electrolyte into said unitary-formed electrode structures; and    placing said unitary-formed electrode structures to sandwich a separator.    
     
     
         9 . The method as claimed in  claim 8 , wherein said unitary-formed electrode structures are placed so that surface-removed sides of said unitary-formed electrode structures are in contact with said separator.  
     
     
         10 . The method as claimed in  claim 8 , wherein said surface part of said base material is removed by a plasma irradiation.  
     
     
         11 . The method as claimed in  claim 8 , wherein said surface part of said base material is removed by a heat treatment.  
     
     
         12 . The method as claimed in  claim 8 , wherein said surface part of said base material is removed by an ozone irradiation.  
     
     
         13 . The method as claimed in  claim 8 , wherein said surface part of said base material is removed by making said surface part of said base material into contact with an organic solvent.  
     
     
         14 . The method as claimed in  claim 8 , wherein said base material is sheet-shaped and said surface part to be removed is one side of said sheet.  
     
     
         15 . The method as claimed in  claim 8 , wherein said separator is placed in opening of said gasket for placing said unitary-formed electrode structures to sandwich said separator before said gasket is adhered with said unitary-formed electrode structures.  
     
     
         16 . The method as claimed in claim  31 , wherein said gasket is adhered with said unitary-formed electrode structures by a curing process.