Sealed battery and method for manufacturing the same

Abstract

A sealed battery includes a metal case which functions as a connection terminal of one polarity and an electrode post which is mounted to the case in an insulated manner and functions as a connection terminal of the other polarity. A sealing section with electrical insulation properties is disposed between the electrode post formed from a hollow cylinder with one closed end and an electrode post through-hole provided in the case. A compression deformation section is produced by deforming the closed end of the electrode post radially outward, for compressing and sealing the sealing section, and for securing the electrode post to the case.

What is claimed is:  
     
         1 . A sealed battery comprising: 
 a metal case which functions as a connection terminal of one polarity, an electrode post through-hole being provided in the case;    an electrode plate assembly housed in the case;    an electrode post which is mounted to the case in an insulated manner and functions as a connection terminal of the other polarity, the electrode post being formed from a hollow cylinder with one closed end;    a sealing section with electrical insulation properties, being disposed between the electrode post and the electrode post through-hole; and    a compression deformation section produced by deforming the closed end of the electrode post radially outward, for compressing and sealing the sealing section, and for securing the electrode post.    
     
     
         2 . The sealed battery according to  claim 1 , wherein 
 the compression deformation section of the electrode post is formed by applying pressure in an axial direction to the closed end of the electrode post in a state where a hollow interior of the electrode post is subjected to fluid pressure.    
     
     
         3 . The sealed battery according to  claim 1 , wherein 
 the electrode post is brought into contact with a collector that is joined to an end face of one polarity of the electrode plate assembly, and an end wall of the compression deformation section of the electrode post is welded to the collector from a position outside the case, through a hollow interior of the electrode post.    
     
     
         4 . The sealed battery according to  claim 3 , wherein 
 the end wall of the compression deformation section and the collector are joined by any of laser beam welding and electron beam welding.    
     
     
         5 . The sealed battery according to  claim 1 , wherein 
 the sealing section comprises an O-ring which is sandwiched in a compressed state between an outside surface of the case and the electrode post, a backup section that regulates the position of the inner and outer peripheries of the O-ring, and an insulating spacer which is disposed between the through-hole and the electrode post, and between the compression deformation section of the electrode post and the inside surface of the case.    
     
     
         6 . The sealed battery according to  claim 1 , wherein 
 a collar that extends radially outwards is provided at the opposite end of the electrode post, and at least one side edge of the collar runs parallel to the edge of the prismatic case.    
     
     
         7 . The sealed battery according to  claim 6 , wherein 
 both side edges of the collar run parallel to the long side surface of the case.    
     
     
         8 . The sealed battery according to  claim 6 , wherein 
 a protrusion that corresponds with the electrode post is formed on the opposite side surface from the side surface of the case of another sealed battery, the surface on which the electrode post is disposed, and at least one side edge of the protrusion and one side edge of the collar are aligned in terms of their relative positions on the protrusion side surface and the electrode post side surface respectively.    
     
     
         9 . The sealed battery according to  claim 6 , wherein 
 a connection plate section that can be elastically displaced in the axial direction of the electrode post is provided on the collar.    
     
     
         10 . A method for manufacturing a sealed battery, comprising: 
 inserting a hollow cylindrical electrode post with one closed end into an electrode post through-hole provided in a lid of a case, with the closed end inserted first and with a sealing section that displays electrical insulation properties and sealing properties disposed between the lid and the electrode post;    compressing the sealing section by subjecting the closed end of the electrode post to an outward expansion in the radial direction and a compression deformation in the axial direction to seal the sealing section, and securing the electrode post to the lid;    housing an electrode plate assembly inside the case;    joining the lid to the case;    joining one end wall of the electrode post to the end face of one polarity of the electrode plate assembly through a hollow interior of the electrode post; and    joining the end face of the other polarity of the electrode plate assembly to the bottom wall of the case.    
     
     
         11 . The method for manufacturing a sealed battery according to  claim 10 , wherein 
 the compression deformation of the electrode post is conducted by applying pressure in the axial direction to the closed end of the electrode post in a state where the hollow interior is subjected to fluid pressure.