Current collector

Abstract

A current collector for a battery in an implantable medical device is presented. The current collector comprises a material that includes a first surface and a second surface. A first set of apertures extend from the first surface to the second surface of the material. A second set of apertures extend from the first surface to the second surface of the material. The second set of apertures are off-set from the first set of apertures.

1 . A current collector for a battery in an implantable medical device comprising: 
 a material which includes a first surface and a second surface;    a first set of apertures that extend from the first surface to the second surface of the material; and    a second set of apertures that extend from the first surface to the second surface of the material, the second set of apertures off-set from the first set of apertures.    
   
   
       2 . The current collector of  claim 1 , wherein the offset being about 15 degrees (°) to 80° from the first and the second set of apertures.  
   
   
       3 . The current collector of  claim 2 , wherein a second offset being about 15 to 80° from the second and the third set of apertures.  
   
   
       4 . The current collector of  claim 1  further comprising: 
 a third set of apertures that extend from the first surface to the second surface of the material, the third set of apertures off-set from the second set of apertures.    
   
   
       5 . The current collector of  claim 1 , wherein the third set of apertures substantially aligned with the first set of apertures.  
   
   
       6 . The current collector of  claim 1 , wherein the first set of apertures being one of substantially triangular, circular, rectangular, elliptical, oval, and diamond.  
   
   
       7 . The current collector of  claim 1 , wherein the second set of apertures being one of substantially triangular, circular, rectangular, elliptical, oval, and diamond.  
   
   
       8 . The current collector of  claim 1 , wherein the third set of apertures being one of substantially triangular, circular, rectangular, elliptical, oval, and diamond.  
   
   
       9 . The current collector of  claim 2 , wherein the off-set minimizes variation in grid stiffness along transverse segments of the current collector.  
   
   
       10 . The current collector of  claim 2 , wherein the off-set increases grid stiffness uniformity along transverse segments of the current collector.  
   
   
       11 . The current collector of  claim 1 , wherein the first and the third set of apertures being substantially aligned.  
   
   
       12 . A current collector for a battery in an implantable medical device comprising: 
 a material which includes a first surface and a second surface;    a first set of apertures that extend from the first surface to the second surface of the material;    a second set of apertures that extend from the first surface to the second surface of the material, the second set of apertures off-set from the first set of apertures in a range of about 15° to about 80°; and    a third set of apertures that extend from the first surface to the second surface of the material, the third set of apertures off-set from the second set of apertures in a range of about 15° to about 80°.    
   
   
       13 . A method of forming a current collector for a battery in an implantable medical device comprising: 
 providing a layer of conductive material;    forming a first set of apertures in the conductive material;    forming a second set of apertures in the conductive material, wherein the second set of apertures being off-set from the first set of apertures in a range of about 15° to 80°.    
   
   
       14 . The method of  claim 13 , further comprising: 
 forming a third set of apertures in the conductive material, the third set of apertures off-set from the second set of apertures in a range of about 15° to about 80°.    
   
   
       15 . The method of  claim 13 , wherein the first set of apertures being one of substantially triangular, circular, rectangular, elliptical, oval, and diamond.  
   
   
       16 . The method of  claim 13 , wherein the second set of apertures being one of substantially triangular, circular, rectangular, elliptical, oval, and diamond.  
   
   
       17 . The method of  claim 13 , wherein the third set of apertures being one of substantially triangular, circular, rectangular, elliptical, oval, and diamond.  
   
   
       18 . The method of  claim 13  further comprising: 
 minimizing variation in grid stiffness along transverse segments of the current collector by off-set between the first and second set of apertures.    
   
   
       19 . The method of  claim 13  further comprising: 
 increasing grid stiffness uniformity along transverse segments of the current collector.    
   
   
       20 . The method of  claim 13  further comprising: 
 preventing at least one sharp bend in the current collector.    
   
   
       21 . An electrode assembly for an electrochemical cell, comprising a metallic current collector having major opposing surfaces, wherein said current collector possesses a characteristic variance in stiffness, wherein the variance in stiffness is the ratio of maximum stiffness to minimum stiffness, and said variance in stiffness has a value of between about one and about two.  
   
   
       22 . An assembly according to  claim 21 , wherein the metallic current collector comprises a substantially common thickness dimension and the characteristic variance in stiffness is due to the juxtaposition of a plurality of apertures distributed over at least a portion of said metallic current collector.  
   
   
       23 . An assembly according to  claim 22 , wherein at least some of said plurality of apertures are offset from adjacent apertures so that the stiffness of said metallic current collector being substantially uniform.  
   
   
       24 . An assembly according to  claim 22 , wherein a linear grouping of at least some of said apertures being offset from a horizontal reference plane at between about 15 degrees and 75 degrees.  
   
   
       25 . An assembly according to  claim 21 , further comprising at least one electrically conductive tab member coupled to a portion of the periphery of said metallic current collector.  
   
   
       26 . An assembly according to  claim 21 , wherein the metallic current collector comprises a first thickness dimension a second thickness dimension different from said first thickness dimension such that the characteristic variance in stiffness being due at least in part to different portions of the metallic current collector having either the first or second thickness dimension.  
   
   
       27 . An assembly according to  claim 26 , wherein the first thickness dimension is greater than the second thickness dimension and said first thickness dimension is disposed along a desired coiling region of the metallic current collector.  
   
   
       29 . An assembly according to claim  28 , further comprising a plurality of apertures disposed over at least a portion of the metallic current collector.  
   
   
       30 . An assembly according to  claim 29 , wherein the current collector comprises at least one of the following materials: a copper material, a titanium material, an aluminum material, a tantalum material, a stainless steel material, a nickel material.  
   
   
       31 . An assembly according to  claim 21 , further comprising an alkali metal containing material coupled to the metallic current collector.