Electrode With Interconnection Design for Miniature Electrochemical Cells and Methods of Making

Abstract

Miniature electrodes and electrochemical cells are disclosed. Such electrodes are made from forming an electrode mixture onto a current collector and distal end of a feedthrough pin such that the current collector and distal end of the feedthrough pin is encapsulated. The methods and electrode assemblies disclosed herein allow such electrode assemblies to be made free from the step of directly attaching a formed electrode to a feedthrough pin and thus simplifying assembly and decreasing size.

1 . A method of making an electrode assembly for an electrochemical cell comprising the steps of:
 attaching a current collector to a distal portion of a feedthrough pin; and   forming a solid electrode electrically coupled to the current collector and the feedthrough pin, the solid electrode encapsulating the current collector and the distal portion of the feedthrough pin.   
     
     
         2 . The method of  claim 1  wherein the solid electrode is formed by compressing an electrode material onto the feedthrough pin and the attached current collector. 
     
     
         3 . The method of  claim 1  wherein the step of attaching a current collector to a feedthrough pin includes welding the current collector to the feedthrough pin. 
     
     
         4 . The method of  claim 1  further comprising the steps of attaching a feedthrough to the feedthrough pin distal from the current collector, fitting a housing cover onto the feedthrough and fitting a feedthrough insulator adjacent to the housing cover and the feedthrough. 
     
     
         5 . The method of  claim 1  wherein the electrode material comprises a mixture of silver vanadium oxide and carbon mono-fluoride. 
     
     
         6 . The method of  claim 1  wherein the step of forming an electrode includes compressing the electrode material with synchronized bidirectional pressing forces. 
     
     
         7 . The method of  claim 1  wherein the current collector has a planar shape. 
     
     
         8 . The method of  claim 5  wherein the bidirectional pressing forces are perpendicular to an axis of the feedthrough pin. 
     
     
         9 . The method of  claim 7  wherein the current collector has a planar shape having major and minor surfaces and the planar current collector is oriented such that the bidirectional pressing forces are applied to the major surfaces of the planar current collector. 
     
     
         10 . The method of  claim 1  wherein the step of pressing the electrode material includes pressing the electrode material within a mold. 
     
     
         11 . An electrode assembly comprising:
 a current collector attached to a distal portion of a feedthrough pin; and   an electrode comprising electrode material encapsulating the attached current collector and the distal portion of the feedthrough pin.   
     
     
         12 . The electrode assembly of  claim 11  wherein the electrode material comprises silver vanadium oxide and carbon mono-fluoride. 
     
     
         13 . The electrode assembly of  claim 11  wherein the current collector is welded to the distal portion of the feedthrough pin. 
     
     
         14 . The electrode assembly of  claim 11  further comprising a feedthrough attached to the feedthrough pin distal from the current collector. 
     
     
         15 . The electrode assembly of  claim 13  further comprising a cover fitted onto the feedthrough. 
     
     
         16 . The electrode assembly of  claim 14  further comprising a feedthrough insulator disposed between the feedthrough and the electrode. 
     
     
         17 . The electrode assembly of  claim 10  wherein the electrode is a cathode. 
     
     
         18 . A method comprising the steps of:
 assembling an electrode assembly comprising the steps of   attaching a current collector to a distal portion of a feedthrough pin and forming a solid first electrode electrically coupled to the current collector and feedthrough pin from a first electrode material coupled to the feedthrough pin and the attached current collector and encapsulating the current collector; and   inserting the electrode assembly into a housing, the housing containing a second electrode electrically coupled to the housing and the housing configured to electrically insulate the first electrode from the housing and the second electrode.   
     
     
         19 . An electrochemical cell comprising:
 a housing;   an electrode assembly partially within the housing, the electrode assembly comprising a current collector attached to a distal portion of a feedthrough pin and a first electrode comprising a first electrode material encapsulating the attached current collector and the distal portion of the feedthrough pin, a proximate portion of the feedthrough pin extending from the housing; and   a second electrode within the housing and electrically coupled to the housing, the first electrode electrically insulated from the housing and the second electrode.   
     
     
         20 . The electrochemical cell of  claim 19  further comprising an electrolyte. 
     
     
         21 . The electrochemical cell of  claim 19  wherein the first electrode is substantially in the form of a cylinder.