Method for producing electrode tab having thickness difference, and rechargeable battery comprising same

Abstract

A method for producing an electrode tab according to an embodiment of the present invention may comprise: a step of preparing a thin plate of a strip shape having a first thickness; a step of forming an adhesion part by compressing the thin plate from one end thereof to a second thickness; and a step of forming, from the other end of the thin plate to the adhesion part, a lead tab part formed to have the first thickness, by releasing the compression applied to the adhesion part.

What is claimed is: 
     
         1 . A rechargeable battery comprising:
 an electrode assembly for charging and discharging a current;   a pouch case for receiving the electrode assembly; and   an electrode tab electrically connected to the electrode assembly,   wherein the electrode tab comprises:
 an adhesion part connected to the electrode assembly; and 
 a lead tab that is thicker than the adhesion part, 
   wherein the adhesion part and the lead tab are integrally formed from a same continuous material having a portion compressed at the adhesion part to cause the lead tab to be thicker than the adhesion part.   
     
     
         2 . The rechargeable battery of  claim 1 , wherein
 a curved part between the adhesion part and the lead tab.   
     
     
         3 . The rechargeable battery of  claim 1 , wherein
 the adhesion part is formed by inserting a thin plate into an adhesion roll and compressing the thin plate from one end thereof in a length direction.   
     
     
         4 . The rechargeable battery of  claim 1 , wherein
 the adhesion part is formed by inserting a thin plate into an adhesion roll and compressing in a width direction of the thin plate.   
     
     
         5 . The rechargeable battery of  claim 1 , wherein
 the adhesion part is formed by providing a thin plate to a press die and compressing with a press punch.   
     
     
         6 . The rechargeable battery of  claim 1 , wherein
 a thickness of the adhesion part is in a range of 1/1.1 to 1/10 of a thickness of the lead tab.   
     
     
         7 . The rechargeable battery of  claim 1 , wherein
 a connecting length of the adhesion part in the electrode assembly is less than a length of the electrode assembly.   
     
     
         8 . The rechargeable battery of  claim 1 , wherein
 a length of the adhesion part is greater than a length of the lead tab.   
     
     
         9 . The rechargeable battery of  claim 1 , wherein
 a length of the adhesion part is in a range of ½ to 5 times a length of the lead tab.   
     
     
         10 . The rechargeable battery of  claim 1 , wherein
 a width of the lead tab is different from a width of the adhesion part.   
     
     
         11 . The rechargeable battery of  claim 1 , wherein
 the electrode assembly includes an uncoated region in which an active material is not coated, and the adhesion part is connected to the uncoated region.   
     
     
         12 . The rechargeable battery of  claim 1 , wherein
 the electrode tab comprises a plurality of electrode tabs, and the electrode assembly includes a plurality of uncoated regions to which the plurality of electrode tabs are connected.   
     
     
         13 . The rechargeable battery of  claim 1 , wherein
 the electrode tab and a current collector of the electrode assembly comprise a same material.   
     
     
         14 . The rechargeable battery of  claim 13 , wherein
 the electrode tab comprises aluminum or copper.   
     
     
         15 . The rechargeable battery of  claim 1 , wherein
 the lead tab protrudes outside the pouch case, and   a protection tape is wound on a portion of the lead tab contacting the pouch case.