Pouch and secondary battery comprising the same

Abstract

Disclosed is a pouch including a first sealing portion wherein an upper sheet and a lower sheet are sealed, and a second sealing portion present in a partial or entire region of the first sealing portion. The pouch further includes a second sealing portion present in a partial or entire region of the first sealing portion, thus efficiently preventing permeation of external moisture and leakage of electrolyte solution through the first sealing portion and enabling fabrication of batteries with improved capacitance maintenance and resistance increase.

1 . A pouch comprising:
 a first sealing portion wherein an upper sheet and a lower sheet are sealed; and   a second sealing portion present in a partial or entire region of the first sealing portion.   
     
     
         2 . The pouch according to  claim 1 , wherein the second sealing portion is formed of an aluminum metal foil tape or an aluminum metal foil tape having at least one surface coated with an electrical insulator. 
     
     
         3 . The pouch according to  claim 2 , wherein the electrical insulator is selected from polyolefin polymers, polyester polymers and nylons. 
     
     
         4 . The pouch according to  claim 1 , wherein the second sealing portion has a thickness of 0.1 to 400 μm. 
     
     
         5 . The pouch according to  claim 1 , wherein the second sealing portion is present in a region where the electrode taps are not located. 
     
     
         6 . The pouch according to  claim 5 , wherein the electrode taps are arranged in identical directions. 
     
     
         7 . The pouch according to  claim 5 , wherein the electrode taps are arranged in different directions. 
     
     
         8 . The pouch according to  claim 1 , wherein when the second sealing portion is formed in a partial region of the first sealing portion, the second sealing portion extends from the end of the first sealing portion. 
     
     
         9 . The pouch according to  claim 1 , wherein the upper sheet and the lower sheet constituting the second sealing portion include an inner layer, a metal layer and an outer layer laminated in this order. 
     
     
         10 . A secondary battery using the pouch according to  claim 1 . 
     
     
         11 . The secondary battery according to  claim 10 , wherein the secondary battery is a lithium secondary battery.