Anode constructions for nonsymmetric capacitors

Abstract

A capacitor of the type having a cathode and an anode and an electrolyte disposed between the cathode and the anode, the capacitor comprising a cathode, an electrolytic anode comprising a stack of metal sheets, the sheets being coated with a metal oxide, wherein the metal sheets are electrically connected in parallel by one or more electrically conductive elements in electrical contact with the sheets, and an electrolyte in contact with the cathode and the metal oxide on the sheets.

What is claimed is:  
     
         1 . A capacitor of the type having a cathode and an anode and an electrolyte disposed between the cathode and the anode, the capacitor comprising 
 a cathode,    an electrolytic anode comprising a stack of metal sheets, the sheets being coated with a metal oxide, wherein the metal sheets are electrically connected in parallel by one or more electrically conductive elements in electrical contact with the sheets, and    an electrolyte in contact with the cathode and the metal oxide on the sheets.    
     
     
         2 . The capacitor of  claim 1  wherein the sheets are rectangular, and the stack is a parallelepiped.  
     
     
         3 . The capacitor of  claim 1  wherein the cathode is an electrochemical cathode comprising a metal current collector coated with a finely divided material.  
     
     
         4 . The capacitor of  claim 1  or  3  wherein openings are formed through the stack of sheets to facilitate communication between the electrolyte and the metal oxide at locations within the interior of the stack of sheets.  
     
     
         5 . The capacitor of  claim 1  or  3  wherein the sheets are separate elements electrically connected at their edges.  
     
     
         6 . The capacitor of  claim 1  or  3  wherein the sheets are a continuous, fan-folded sheet, with each fold forming one sheet in the stack.  
     
     
         7 . The capacitor of  claim 3  wherein the finely divided material comprises carbon particles and the capacitance of the electrochemical cathode is provided by a double layer effect.  
     
     
         8 . The capacitor of  claim 3  wherein the finely divided material comprises a conducting metal oxide and the capacitance of the electrochemical cathode is provided by an oxidation reduction reaction.  
     
     
         9 . The capacitor of  claim 3  wherein the electrolyte is substantially nonaqueous.  
     
     
         10 . A capacitor of the type having a cathode and an anode and an electrolyte disposed between the cathode and the anode, the capacitor comprising 
 an electrochemical cathode comprising a metal layer coated with a finely divided material,    an electrolytic anode winding comprising at least one oxide-coated metal layer wound into a winding, and    an electrolyte in contact with the cathode and the metal oxide in the anode winding.    
     
     
         11 . The capacitor of  claim 10  wherein the cathode is adjacent the anode winding, so that the cathode extends generally in a plane normal to the axis about which the anode is wound.  
     
     
         12 . The capacitor of  claim 11  wherein there are a plurality of cathodes and a plurality of anode windings and the cathodes are interleaved between the anode windings.  
     
     
         13 . The capacitor of  claim 11  wherein there are a plurality of anode windings arranged in an anode layer and wherein the cathode comprises at least one layer forming a cathode layer positioned generally parallel to the anode layer and normal to the axis about which the anode windings are wound.  
     
     
         14 . The capacitor of  claim 13  wherein there are a plurality of interleaved anode and cathode layers.  
     
     
         15 . The capacitor of  claim 10  wherein the anode windings are circular or oval in cross section.  
     
     
         16 . The capacitor of  claim 10  wherein the finely divided material comprises carbon particles and the capacitance of the electrochemical cathode is provided by a double layer effect.  
     
     
         17 . The capacitor of  claim 10  wherein the finely divided material comprises a conducting metal oxide and the capacitance of the electrochemical cathode is provided by an oxidation reduction reaction.  
     
     
         18 . The capacitor of  claim 10  wherein the electrolyte is substantially nonaqueous.  
     
     
         19 . A capacitor of the type having a cathode and an anode and an electrolyte disposed between the cathode and the anode, the capacitor comprising 
 a cathode,    an electrolytic anode winding comprising a plurality of oxide-coated metal layers wound about an axis, wherein the metal layers are electrically connected in parallel by one or more electrically conductive elements in electrical contact with the layers, and    an electrolyte in contact with the cathode and the metal oxide on the layers.    
     
     
         20 . The capacitor of  claim 20  wherein there are at least three oxide-coated layers wound to form the anode winding.  
     
     
         21 . A capacitor of the type having a cathode and an anode and an electrolyte, the capacitor comprising 
 an electrolytic anode comprising a plurality of oxide-coated metal layers arranged one layer over another layer, and    an electrochemical cathode comprising at least one metal layer coated with a finely divided material, wherein the coated layer of the cathode is arranged substantially parallel to the plurality of anode layers,    wherein the layers of the anode each include a multiplicity of tiny holes extending substantially all the way through the layer to provide paths for conductive ions to flow between the cathode layer and the anode layers.    
     
     
         22 . The capacitor of  claim 21  wherein the layers of the anode and cathode are wound into a winding.  
     
     
         23 . The capacitor of  claim 21  wherein the layers of the anode and cathode are stacked in a stack.  
     
     
         24 . The capacitor of  claim 21  further comprising spacer layers separating the anode layers from the cathode layers.  
     
     
         25 . The capacitor of claims  19  or  21  wherein the electrolyte is substantially nonaqueous.