Electrode and current collector for electrochemical capacitor having double electric layer and double electric layer electrochemical capacitor formed therewith

Abstract

An electrode and a DEL capacitor formed therewith. The electrode will typically be a polarizable electrode, and may be formed of an activated carbon material having a substantially zero ash percentage and a low percentage of transition metals. In constructing a DEL capacitor employing such an electrode, a non-polarizable electrode formed from a lead dioxide/lead sulfate compound is preferably also used. The DEL capacitor may utilize an acid-based electrolyte, such as an aqueous sulfuric acid electrolyte. Consequently, the present invention also includes a current collector that preferably comprises a base material formed from a lead or a lead compound and a protective coating material that is resistant to an acid-based electrolyte. Preferably, the protective coating material is formed from a polymer base and a conductive dope that may thereafter be applied to the current collector base material by a variety of methods.

1 . An electrode for use in an electrochemical capacitor, said electrode consisting essentially of:
 an active material comprising an activated carbon obtained from the carbonization and subsequent activation of a furane tar and/or a furane resin; and   a binder consisting of a fluorine-containing polymer;   wherein said binder is present in said electrode in an amount of between about 0.5 and about 5.0 weight percent.   
   
   
       2 . The electrode of  claim 1 , wherein said electrode is polarizable. 
   
   
       3 . The electrode of  claim 1 , wherein said binder includes a fluoroplastic emulsion. 
   
   
       4 . The electrode of  claim 1 , wherein the specific capacitance of said electrode is between about 900 and about 1,000 F/g in a sulfuric acid electrolyte. 
   
   
       5 . The electrode of  claim 1 , wherein said activated carbon includes a concentration of less than 500 parts per million of transition metals. 
   
   
       6 . The electrode of  claim 1 , wherein said activated carbon is no greater than 100 micrometers. 
   
   
       7 . The electrode of  claim 1 , wherein said binder includes a fluorinated polyolefin. 
   
   
       8 . An electrode for use in an electrochemical capacitor, said electrode consisting essentially of:
 an active material comprising an activated carbon obtained from the carbonization and subsequent activation of a furane tar and/or a furane resin; and   a binder consisting of a fluorine-containing polymer;   wherein said binder is present in said electrode in an amount of between about 0.5 and about 5.0 weight percent, the electrode is polarizable.   
   
   
       9 . The electrode of  claim 8 , wherein said binder includes a fluoroplastic emulsion. 
   
   
       10 . The electrode of  claim 8 , wherein the specific capacitance of said electrode is between about 900 and about 1,000 F/g in a sulfuric acid electrolyte. 
   
   
       11 . The electrode of  claim 8 , wherein said activated carbon includes a concentration of less than 500 parts per million of transition metals. 
   
   
       12 . The electrode of  claim 8 , wherein said activated carbon is no greater than 100 micrometers. 
   
   
       13 . The electrode of  claim 8 , wherein said binder includes a fluorinated polyolefin.