Electric storage device

Abstract

An electric storage device is provided having a structure that can reliably produce the sealing effect between a case and a sealing member. The electric storage device of the present invention includes an electrode assembly; a case that includes a defining wall and houses the electrode assembly; a sealing member that is arranged on the defining wall; and a conductive member that is electrically connected to the electrode assembly, the conductive member being supported by the sealing member, wherein at least a portion of the defining wall where the sealing member is arranged is made of an aluminum-based metallic material; and the sealing member is made of a material that is softer than the material for the at least a portion of the defining wall where the sealing member is arranged.

1 . An electric storage device comprising:
 an electrode assembly;   a case that includes a defining wall and houses the electrode assembly;   a sealing member that is arranged on the defining wall; and   a conductive member that is electrically connected to the electrode assembly, the conductive member being supported by the sealing member,   wherein at least a portion of the defining wall where the sealing member is arranged comprises an aluminum-based metallic material; and   the sealing member comprises a material that is softer than the material for the at least a portion of the defining wall where the sealing member is arranged.   
     
     
         2 . The electric storage device according to  claim 1 , wherein
 the sealing member comprises an engineering plastic.   
     
     
         3 . The electric storage device according to  claim 2 , wherein
 the sealing member comprises polyphenylene sulfide (PPS) resin and elastomer.   
     
     
         4 . The electric storage device according to  claim 3 , wherein
 the elastomer is contained in an amount of 2 to 20% by weight.   
     
     
         5 . The electric storage device according to  claim 1 , wherein
 the sealing member has a Rockwell hardness (R scale) of 55 to 120.   
     
     
         6 . The electric storage device according to  claim 1 , wherein the sealing member is arranged on an outer surface of the defining wall, the device further comprising:
 a terminal retainer arranged on the outer surface of the defining wall; and   an external terminal that is supported by the terminal retainer,   wherein the conductive member is an auxiliary terminal that passes through the defining wall and is electrically connected to the external terminal.   
     
     
         7 . The electric storage device according to  claim 1 , wherein the sealing member is arranged on an outer surface of the defining wall, the device further comprising:
 an external terminal that is supported, together with the conductive member, by the sealing member,   wherein the conductive member is an auxiliary terminal that passes through the defining wall and is electrically connected to the external terminal.   
     
     
         8 . The electric storage device according to  claim 1 , wherein
 the sealing member is arranged on an outer surface of the defining wall; and   the conductive member is an external terminal that passes through the defining wall.   
     
     
         9 . The electric storage device according to  claim 6 , wherein
 the auxiliary terminal includes a body and an insertion part that is formed continuously with the body;   the sealing member includes a surrounding circumferential outer wall part and a recess inside the outer wall part; and   the outer wall part is formed to be high enough for the recess to entirely or substantially entirely receive the body of the auxiliary terminal.   
     
     
         10 . The electric storage device according to  claim 9 , wherein
 a space is provided between the outer wall part of the sealing member and the body of the auxiliary terminal.   
     
     
         11 . The electric storage device according to  claim 7 , wherein
 the auxiliary terminal includes a body and an insertion part that is formed continuously with the body;   the external terminal includes a head and a shaft projecting from a first surface of the head;   the sealing member includes a surrounding circumferential outer wall part and a recess inside the outer wall part; and   the outer wall part is formed to be high enough for the recess to entirely or substantially entirely receive the body of the auxiliary terminal and the head of the external terminal.   
     
     
         12 . The electric storage device according to  claim 11 , wherein
 spaces are provided between the outer wall part of the sealing member and the body of the auxiliary terminal and between the outer wall part of the sealing member and the head of the external terminal.   
     
     
         13 . The electric storage device according to  claim 8 , wherein
 the external terminal includes a head and a shaft projecting from a first surface of the head;   the sealing member includes a surrounding circumferential outer wall part and a recess inside the outer wall part; and   the outer wall part is formed to be high enough for the recess to entirely or substantially entirely receive the head of the external terminal.   
     
     
         14 . The electric storage device according to  claim 13 , wherein
 a space is provided between the outer wall part of the sealing member and the head of the external terminal.   
     
     
         15 . The electric storage device according to  claim 9 , further comprising:
 a current collector that electrically connects the electrode assembly to the auxiliary terminal, the current collector having a through-hole and being housed in the case together with the electrode assembly, wherein   the defining wall of the case has a through-hole at least in a portion thereof;   the sealing member has a through-hole formed in a bottom surface of the recess, and an annular projection that projects around the through-hole to be inserted through the through-hole of the case;   the insertion part of the auxiliary terminal includes a crimping part that is crimped in a state where the crimping part has been inserted through the through-hole of the sealing member and the through-hole of the current collector; and   the crimping part has a hollow portion having a length that does not reach a position of an inner surface of the case.   
     
     
         16 . The electric storage device according to  claim 11 , further comprising:
 a current collector that electrically connects the electrode assembly to the external terminal, the current collector having a through-hole and being housed in the case together with the electrode assembly, wherein   the defining wall of the case has a through-hole at least in a portion thereof;   the sealing member has a through-hole formed in a bottom surface of the recess, and an annular projection that projects around the through-hole to be inserted through the through-hole of the case;   the external terminal includes a crimping part that projects from a second surface of the head and is crimped in a state where the crimping part has been inserted through the through-hole of the sealing member and the through-hole of the current collector; and   the crimping part has a hollow portion having a length that does not reach a position of an inner surface of the case.   
     
     
         17 . The electric storage device according to  claim 1 , wherein
 the conductive member is crimped in such a manner that the sealing member is pressed against the defining wall.   
     
     
         18 . A method of manufacturing an electric storage device, the device comprising:
 an electrode assembly;   a case that includes a defining wall and houses the electrode assembly;   a sealing member that is arranged on the defining wall; and   a conductive member that is electrically connected to the electrode assembly, the conductive member being supported by the sealing member,   wherein at least a portion of the defining wall where the sealing member is arranged comprises an aluminum-based metallic material; and   the sealing member comprises a material that is softer than the material for the at least a portion of the defining wall where the sealing member is arranged, the method comprising:   crimping the conductive member in such a manner that the sealing member is pressed against the defining wall.