JP2017084575A - battery - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a battery which is excellent in electrical connection between a protrusion of an electrode connection member and a hole inner peripheral surface of an external terminal member (small contact resistance).SOLUTION: A hole inner peripheral surface 37d (47d) of an external terminal member 37 (47) constituting a terminal through-hole 37b (47b) has a pointed pat 37k (47k) formed in a pointed shape toward radially inside of the terminal through-hole 37b (47b). At least the tip 37n (47n) of the pointed shape 37k (47k) is in contact with the inside of a protrusion 32 (42) while being inserted into the inside of the protrusion 32 (42) from the outer peripheral surface 32h (42h) of the protrusion 32 (42) of an electrode connection member 35 (45).SELECTED DRAWING: Figure 6

Description

  The present invention relates to a battery.

  Patent Document 1 discloses an electrode body having a positive electrode and a negative electrode, a battery case that accommodates the electrode body, an electrode body connection portion that is located in the battery case and is connected to the electrode body, and an outside of the battery case. A metal electrode connecting member (internal terminal) having a columnar protruding portion that protrudes into the terminal, and an external terminal member positioned outside the battery case, through which the protruding portion of the electrode connecting member is inserted A battery including a metal external terminal member having a hole is disclosed. In this battery, the external terminal member and the electrode connecting member are fixed to the battery case in a state where the protruding portion is inserted into the terminal through hole and the protruding portion is crimped and deformed.

JP 2009-37817 A

  Furthermore, in the battery of Patent Document 1, a plurality of vertical grooves (dents) are formed on the inner peripheral surface of the external terminal member constituting the terminal through hole. Then, the projecting portion of the electrode connecting member is caulked and deformed (specifically, the portion of the projecting portion located in the terminal through hole is expanded in diameter), so that the electrode connection is formed in the longitudinal groove of the terminal through hole. It has been proposed that the outer peripheral surface of the protruding portion of the member is deformed and bitten. By doing so, the external terminal member and the electrode connection member are firmly joined, and the contact resistance between the protruding portion of the electrode connection member and the inner peripheral surface of the hole of the external terminal member is stabilized.

  However, in the method disclosed in Patent Document 1, it is possible to sufficiently (appropriately) bite the outer peripheral surface of the protruding portion of the electrode connecting member into the vertical groove on the inner peripheral surface of the terminal through hole. was difficult. For this reason, it is difficult to improve the electrical connection (reducing contact resistance) between the protruding portion of the electrode connecting member and the inner peripheral surface of the hole of the external terminal member.

  Further, even if the outer peripheral surface of the protruding portion of the electrode connecting member is deformed into the vertical groove on the inner peripheral surface of the terminal through hole, the protruding portion of the electrode connecting member and the hole of the external terminal member In some cases, the electrical connection with the peripheral surface cannot be improved (contact resistance is reduced). Specifically, since the metal electrode connection member is exposed to the atmosphere, an oxide film (thin-film metal oxide) is formed on the outer peripheral surface of the protrusion (the outer peripheral surface is formed of the oxide film). There are). In such a case, even if the outer peripheral surface of the projecting portion of the electrode connecting member is deformed into the vertical groove on the inner peripheral surface of the terminal through hole, the projecting portion of the electrode connecting member and the external terminal The hole inner peripheral surface of the member comes into contact with the oxide film. When the electrical resistance of the oxide film was large, the electrical connection between the protruding portion of the electrode connecting member and the inner peripheral surface of the hole of the external terminal member could not be improved (contact resistance was reduced).

  The present invention has been made in view of the current situation, and provides a battery with good electrical connection (low contact resistance) between the protruding portion of the electrode connecting member and the inner peripheral surface of the hole of the external terminal member. The purpose is to do.

  One aspect of the present invention includes an electrode body having a positive electrode and a negative electrode, a battery case that houses the electrode body, an electrode body connection portion that is located in the battery case and is connected to the electrode body, and the battery case A metal electrode connecting member having a columnar protruding portion that protrudes to the outside, and an external terminal member positioned outside the battery case, the terminal through hole through which the protruding portion of the electrode connecting member is inserted An external terminal member made of metal, and the external terminal member and the electrode connecting member are connected to the battery case in a state where the protruding portion is inserted into the terminal through-hole and the protruding portion is deformed by caulking. In the battery fixed to the terminal, the inner peripheral surface of the external terminal member constituting the terminal through hole has a pointed shape (V-shaped cross section) that is pointed toward the radially inner side of the terminal through hole. The cusp At least the tip part (the part located radially inside) of the part enters the inside of the projecting part from the outer peripheral surface of the projecting part (the state of being stuck), and the inside of the projecting part (of the projecting part) Among them, the battery is in contact with a portion located radially inward from the outer peripheral surface.

  In the battery described above, the inner circumferential surface of the terminal through hole (through hole through which the protruding portion of the electrode connecting member is inserted) of the external terminal member is directed radially inward (center side) of the terminal through hole. It has a pointed portion having a pointed shape (V-shaped cross section). Further, at least the tip portion (a portion located radially inside) of the pointed portion enters the inside of the projecting portion from the outer peripheral surface of the projecting portion (the state of being stuck), and the inside of the projecting portion (projecting) Of the portion is in contact with a portion located radially inside the outer peripheral surface.

  Thereby, the protrusion part of an electrode connection member and the internal peripheral surface of a hole of an external terminal member can be connected reliably (the stable connection state of both can be ensured), and the protrusion part of an electrode connection member and the exterior The electrical connection between the terminal member and the inner circumferential surface of the hole can be improved (contact resistance can be reduced).

  In particular, even in the case where an oxide film (thin film-like metal oxide) is formed on the outer peripheral surface of the protruding portion of the electrode connecting member (the outer peripheral surface is formed of an oxide film), in the battery described above, the external terminal member At least the tip of the pointed portion on the inner peripheral surface of the hole (part located on the inner side in the radial direction) breaks through the oxide film and enters the inside of the protruding portion from the outer peripheral surface of the protruding portion. Accordingly, at least the tip of the pointed portion on the inner peripheral surface of the hole of the external terminal member is in contact with the metal portion (non-oxidized metal portion) located on the radial inner side of the oxide film in the protruding portion. It becomes. For this reason, electrical connection between the electrode connecting member (protruding portion) and the external terminal member (hole inner peripheral surface) can be improved (contact resistance can be reduced).

  In the battery described above, the electrode connection member and the external terminal member are at least one electrode connection member and an external terminal member of a positive electrode and a negative electrode. That is, (1) when the electrode connection member and the external terminal member are only a positive electrode connection member and a positive electrode external terminal member, (2) the electrode connection member and the external terminal member are a negative electrode connection member and a negative electrode external terminal. Either of the members, or (3) the electrode connection member and the external terminal member are both a positive electrode connection member and a positive electrode external terminal member, and a negative electrode connection member and a negative electrode external terminal member.

  Further, the electrode body having a positive electrode and a negative electrode, a battery case that accommodates the electrode body, an electrode body connection portion that is located in the battery case and is connected to the electrode body, and the case through hole of the battery case A metal electrode connection member having a columnar protrusion protruding outside the battery case, and an external terminal member positioned outside the battery case, the terminal through which the protrusion of the electrode connection member is inserted An external terminal member made of metal having a through-hole, and the external terminal member and the electrode connecting member are inserted into the terminal through-hole and the protruding portion is caulked and deformed. In the method of manufacturing a battery fixed to the battery case, a caulking process for caulking and deforming the projecting portion while the projecting portion projecting from the case through hole is inserted into the terminal through hole. The hole inner peripheral surface of the external terminal member constituting the terminal through hole has a pointed portion that has a pointed shape (V-shaped cross section) toward the radially inner side of the terminal through hole. The caulking step expands the diameter of a portion of the protruding portion located in the terminal through hole, so that at least the tip portion (the portion located on the radially inner side) of the pointed portion is A method of manufacturing a battery including a step of expanding the diameter of the protrusion by entering (piercing) the protrusion from the outer peripheral surface of the protrusion and contacting the inside of the protrusion (a portion located radially inward of the outer peripheral surface). Is preferred.

  According to the above manufacturing method, the above-described battery (the battery which is one embodiment of the present invention) can be manufactured. Therefore, according to the manufacturing method described above, it is possible to manufacture a battery having good electrical connection (low contact resistance) between the protruding portion of the electrode connecting member and the inner peripheral surface of the hole of the external terminal member.

It is sectional drawing of the battery concerning embodiment. It is an enlarged view of the B section and C section of FIG. It is a disassembled perspective view of the battery case cover with a terminal concerning an embodiment. It is a perspective view of the external terminal member concerning an embodiment. It is FF sectional drawing of FIG. It is the G section enlarged view of FIG. It is a flowchart (main routine) which shows the flow of the manufacturing method of the battery concerning embodiment. It is another flowchart (subroutine) which shows the flow of the manufacturing method of the battery concerning embodiment. It is a figure explaining the 1st crimping process which crimps the protrusion front-end | tip part of a protrusion part. It is another figure explaining the 1st crimping process which crimps the protrusion front-end | tip part of a protrusion part. It is a figure explaining the 2nd crimping process which expands the diameter of the protrusion insertion part of a protrusion part. It is the elements on larger scale of the external terminal member concerning a modification.

(Embodiment)
Next, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a cross-sectional view of a battery 1 according to this embodiment. FIG. 2 is an enlarged view of a portion B and a portion C in FIG. In addition, about the member different from B part among the members in C part, the code | symbol is written in parenthesis in FIG. FIG. 3 is an exploded perspective view of a part of the terminal-equipped battery case lid 15 according to the present embodiment.

  As shown in FIG. 1, the battery 1 according to this embodiment is a lithium ion secondary battery including a battery case 10 and an electrode body 50 accommodated in the battery case 10. The battery case 10 includes a rectangular box-shaped battery case main body 11 having an opening 11d and a lid 13 that closes the opening 11d of the battery case main body 11. The battery case main body 11 and the lid 13 are integrated by welding all around. In the present embodiment, as will be described later, the battery case lid 15 with terminals is formed by assembling the lid 13 and other members.

  The electrode body 50 has an oval cross section, and is a flat type wound by winding a sheet-like separator 57 between a sheet-like positive electrode plate 55 and a sheet-like negative electrode plate 56. Is the body. The electrode body 50 is positioned at one end portion (left end portion in FIG. 1) in the axial direction (left and right direction in FIG. 1), and a positive electrode winding portion 55b in which only a part of the positive electrode plate 55 is spirally overlapped; It is located at the other end (right end in FIG. 1), and has a negative electrode winding part 56b in which only a part of the negative electrode plate 56 overlaps in a spiral shape. A positive electrode mixture layer containing a positive electrode active material is formed on the positive electrode plate 55 at a portion excluding the positive electrode winding part 55b. Similarly, in the negative electrode plate 56, a negative electrode mixture layer containing a negative electrode active material is formed in a portion excluding the negative electrode winding part 56b.

  The battery case lid 15 with a terminal includes a lid body 13, a first insulating member 80, a positive electrode terminal member 30, a negative electrode terminal member 40, and a second insulating member 70. Among these, the lid body 13 has an elongated flat plate shape, and circular through holes (case through holes) 13h and 13k penetrating the lid body 13 at both ends in the longitudinal direction (left and right direction in FIG. 1). Is formed. In addition, a safety valve 13j is provided at the center of the lid 13 in the longitudinal direction. A liquid injection port 13n for injecting an electrolyte (not shown) into the battery case body 11 is formed between the safety valve 13j and the through hole 13k. The liquid injection port 13n is sealed with a liquid injection stopper 13m.

  The positive electrode terminal member 30 includes a positive electrode connection member 35 (electrode connection member), a positive electrode external terminal member 37 (external terminal member), and a positive electrode fastening member 39 (see FIGS. 1 to 3). Among these, the positive electrode connection member 35 is made of metal (specifically, aluminum), is connected to the positive electrode winding portion 55 b of the electrode body 50, and extends to the outside of the battery case 10 through the through hole 13 h of the lid body 13. I'm out. The positive electrode external terminal member 37 is made of metal (specifically, aluminum), is located above the lid 13 (outside of the battery case 10), and is electrically connected to the positive electrode connection member 35 outside the battery case 10. doing. The positive electrode fastening member 39 is a bolt made of metal, is located outside the battery case 10, and fastens the positive electrode external terminal member 37 and a bus bar (not shown).

  The negative electrode terminal member 40 includes a negative electrode connection member 45 (electrode connection member), a negative electrode external terminal member 47 (external terminal member), and a negative electrode fastening member 49 (see FIGS. 1 to 3). Among these, the negative electrode connection member 45 is made of metal (specifically, copper), is connected to the negative electrode winding portion 56 b of the electrode body 50, and extends to the outside of the battery case 10 through the through hole 13 k of the lid body 13. I'm out. The negative electrode external terminal member 47 is made of metal (specifically, copper), is located above the lid 13 (outside of the battery case 10), and is electrically connected to the negative electrode connection member 45 outside the battery case 10. doing. The negative electrode fastening member 49 is a bolt made of metal, is located outside the battery case 10 and fastens the negative electrode external terminal member 47 and a bus bar (not shown).

  The positive electrode external terminal member 37 (negative electrode external terminal member 47) is made of a metal plate and has a substantially Z shape in side view (see FIGS. 1, 3, and 4). The positive external terminal member 37 is made of an aluminum plate, and the negative external terminal member 47 is made of a copper plate. The positive external terminal member 37 (negative external terminal member 47) includes a pressing part 37f (pressing part 47f), a separating part 37g (separating part 47g), and a pressing part 37f (pressing part 47f) and a separating part 37g (separating part). 47g) and a connecting portion 37h (connecting portion 47h). Among these, the pressing part 37f (pressing part 47f) has a flat plate shape, and is pressed by the protruding tip part 33 (projecting tip part 43) of the projecting part 32 (projecting part 42) described later, whereby the first insulating member 80 is pressed. It is a site | part which presses.

  The separation part 37g (separation part 47g) is a flat plate-like part that is located above the lid 13 and is spaced apart from the pressing part 37f (pressing part 47f) and extends in parallel with the pressing part 37f (pressing part 47f). . A through hole 37b (through hole 47b) (corresponding to a terminal through hole) is formed in the pressing part 37f (pressing part 47f), and the through hole 37b (through hole 47b) includes The protrusion 32 (protrusion 42) of the positive electrode connection member 35 (negative electrode connection member 45) is inserted (see FIG. 2). Further, a through-hole 37c (through-hole 47c) penetrating therethrough is also formed in the separation part 37g (separation part 47g).

  The positive electrode fastening member 39 (negative electrode fastening member 49) is a metal bolt and has a rectangular plate-shaped head portion 39b (head portion 49b) and a columnar shaft portion 39c (shaft portion 49c). (See FIGS. 1 and 3). A portion on the tip side of the shaft portion 39c (shaft portion 49c) is a screw portion 39d (screw portion 49d). The shaft portion 39c (shaft portion 49c) of the positive electrode fastening member 39 (negative electrode fastening member 49) is inserted through the through hole 37c (through hole 47c) of the positive electrode external terminal member 37 (negative electrode external terminal member 47).

  The second insulating member 70 is made of a resin that is electrically insulating and elastically deformable, and includes a first interposition part 71, an insulating side wall part 73, and an insulating insertion part 75 (see FIGS. 2 and 3). ). Among these, the 1st interposition part 71 comprises flat plate shape, and has the circular through-hole 71b which penetrates the protrusion part 32 (protrusion part 42) of the positive electrode terminal member 30 (negative electrode terminal member 40) in the center part. ing. The first interposition part 71 is compressed in the axial direction (direction along the axis AX), and the upper surface 31f (upper surface 41f) of the pedestal portion 31 (pedestal portion 41) of the positive electrode terminal member 30 (negative electrode terminal member 40). ) And the lower surface 13b of the lid body 13.

  The insulating side wall 73 is a square annular side wall located on the periphery of the first interposition part 71. The insulating side wall 73 surrounds the outer peripheral side 31g (outer peripheral side 41g) of the pedestal 31 (pedestal 41). The insulating insertion part 75 has a cylindrical shape protruding from the upper surface 71 f of the first interposition part 71. The insulating insertion portion 75 surrounds the lower portion of the protruding portion 32 (the protruding portion 42) of the positive electrode connecting member 35 (the negative electrode connecting member 45), and is in the through hole 13h (through hole 13k) of the lid body 13. And compressed in the axial direction (direction along the axis AX). The second insulating member 70 electrically insulates the positive electrode connecting member 35 (negative electrode connecting member 45) and the lid 13 and seals between the positive electrode connecting member 35 (negative electrode connecting member 45) and the lid 13. It has stopped.

  The first insulating member 80 is made of a resin that has electrical insulation and is elastically deformable, and is disposed in contact with the upper surface 13p (front surface) of the lid 13 (see FIGS. 2 and 3). The first insulating member 80 is interposed between the lid 13 and the positive external terminal member 37 (negative external terminal member 47) to electrically insulate both. The first insulating member 80 includes a head arrangement portion 81 where a head portion 39b of the positive electrode fastening member 39 (a head portion 49b of the negative electrode fastening member 49) is arranged, and a pressing portion 37f (a negative electrode external portion) of the positive electrode external terminal member 37. A portion (referred to as an insulating force receiving portion 83) that is pressed by the pressing portion 47 f) of the terminal member 47 and comes into contact with the upper surface 13 p (front surface) of the lid body 13 is provided. Among these, the insulating force receiving portion 83 has a plate shape. The insulating force receiving portion 83 of the first insulating member 80 is formed with a through-hole 80b (insulating through-hole) that penetrates itself. The protruding portion 32 of the positive electrode terminal member 30 (the protruding portion 42 of the negative electrode terminal member 40) is inserted into the through hole 80b.

  The positive electrode connecting member 35 includes a pedestal portion 31, a protruding portion 32, and an electrode body connecting portion 34 (see FIGS. 1 to 3). Among these, the pedestal portion 31 has a rectangular plate shape and is located inside the battery case 10. The electrode body connecting portion 34 is located in the battery case 10 and extends from the pedestal portion 31 to the bottom surface 11b side of the battery case main body portion 11, and is connected to the positive electrode winding portion 55b of the electrode body 50. The protruding portion 32 is a cylindrical portion extending from the upper surface 31 f of the pedestal portion 31, and the through hole 70 b of the second insulating member 70, the through hole 13 h (lid through hole) of the lid body 13, and the through hole of the first insulating member 80. 80b (insulating through hole) and the through hole 37b (terminal through hole) of the positive electrode external terminal member 37 are inserted to protrude outside the battery case 10 (see FIG. 2).

  As shown in FIG. 9, the protruding tip portion 33, which is the tip portion of the protruding portion 32, has a cylindrical shape before being deformed by caulking. The protruding tip 33 is pushed and expanded in a direction from the inner peripheral surface 33g of the protruding tip 33 toward the outer peripheral surface 33h when a caulking load F is applied from one side (upper side in FIG. 9) to itself (see FIG. 9). The positive electrode external terminal member 37 is pressed in the load direction of the caulking load F (downward in FIG. 9). As a result, the second insulating member 70, the lid body 13, the first insulating member 80, and the positive electrode external terminal member 37 are narrowed between the protruding tip portion 33 and the pedestal portion 31, and the second insulating member 70 and the lid The body 13, the first insulating member 80, and the positive external terminal member 37 are fastened.

  Therefore, in the battery 1 according to the present embodiment, the protruding portion 32 of the positive electrode connection member 35 includes the through hole 70 b of the second insulating member 70, the through hole 13 h (lid through hole) of the lid body 13, and the first insulating member 80. The positive external terminal member 37 and the positive electrode connecting member are inserted into the through hole 80b (insulating through hole) and the through hole 37b (terminal through hole) of the positive electrode external terminal member 37 and the protruding portion 32 is deformed by caulking. 35, the second insulating member 70, and the first insulating member 80 are fixed to the battery case 10 (specifically, the lid 13).

  The negative electrode connection member 45 includes a pedestal portion 41, a protruding portion 42, and an electrode body connection portion 44 (see FIGS. 1 to 3). Among these, the pedestal portion 41 has a rectangular plate shape and is located inside the battery case main body portion 11. The electrode body connection portion 44 is located in the battery case 10 and is connected to the negative electrode winding portion 56 b of the electrode body 50 in a form extending from the pedestal portion 41 to the bottom surface 11 b side of the battery case main body portion 11. The protruding portion 42 is a cylindrical portion extending from the upper surface 41 f of the pedestal portion 41, and the through hole 70 b of the second insulating member 70, the through hole 13 k (lid through hole) of the lid body 13, and the through hole of the first insulating member 80. 80b (insulating through-hole) and the through-hole 47b (terminal through-hole) of the negative electrode external terminal member 47 are inserted to protrude outside the battery case 10 (see FIG. 2).

  As shown in FIG. 9, the protruding tip portion 43, which is the tip portion of the protruding portion 42, has a cylindrical shape before being deformed by caulking. The protruding tip portion 43 is pushed and expanded in a direction from the inner peripheral surface 43g of the protruding tip portion 43 to the outer peripheral surface 43h when a caulking load F is applied from one side (upper side in FIG. 9) to itself (see FIG. 9). In addition to being deformed so as to increase in diameter, the negative external terminal member 47 is pressed in the load direction of the caulking load F (downward in FIG. 9). As a result, the second insulating member 70, the lid body 13, the first insulating member 80, and the negative electrode external terminal member 47 are narrowed between the protruding tip portion 43 and the pedestal portion 41, and the second insulating member 70 and the lid The body 13, the first insulating member 80, and the negative external terminal member 47 are fastened.

  Therefore, in the battery 1 according to the present embodiment, the protruding portion 42 of the negative electrode connection member 45 has the through hole 70 b of the second insulating member 70, the through hole 13 h (lid through hole) of the lid body 13, and the first insulating member 80. The negative external terminal member 47 and the negative electrode connecting member are inserted into the through hole 80b (insulating through hole) and the through hole 37b (terminal through hole) of the negative external terminal member 47 and the protruding portion 42 is deformed by caulking. 45, the second insulating member 70, and the first insulating member 80 are fixed to the battery case 10 (specifically, the lid 13).

  Furthermore, in the battery 1 according to the present embodiment, as shown in FIG. 5, the inner peripheral surface 37 d of the positive external terminal member 37 constituting the through hole 37 b (terminal through hole) of the positive external terminal member 37 is a through hole. It has a pointed portion 37k having a pointed shape (V-shaped cross section) toward the radially inner side (center side) of 37b. Furthermore, as shown in FIG. 6, which is an enlarged view of the G part in FIG. 2, at least the tip part 37 n (site located radially inside) of the pointed part 37 k is the protrusion 32 of the positive electrode connecting member 35. In a state where the protrusion 32 has entered the protruding portion 32 from the outer peripheral surface 32h (a pierced state), the inner metal 32k of the protruding portion 32 (a portion located radially inward of the outer peripheral surface 32h) is in contact.

  Thereby, the protrusion part 32 of the positive electrode connection member 35 and the hole inner peripheral surface 37d of the positive electrode external terminal member 37 can be reliably connected (a stable connection state of both can be ensured), and the positive electrode connection member The electrical connection between the projecting portion 32 of 35 and the hole inner peripheral surface 37d of the positive electrode external terminal member 37 can be improved (contact resistance is reduced).

  By the way, since the positive electrode connecting member 35 is made of aluminum, as shown in FIG. 6, an oxide film 32j (specifically, an aluminum oxide film) is formed on the outer peripheral surface 32h of the protrusion 32 of the positive electrode connecting member 35. It is formed (the outer peripheral surface 32h is formed by the oxide film 32j). For this reason, the protrusion 32 of the positive electrode connection member 35 and the hole inner periphery of the positive electrode external terminal member 37 are simply brought into contact with the protrusion 32 of the positive electrode connection member 35 and the hole inner peripheral surface 37 d of the positive electrode external terminal member 37. The surface 37d comes into contact with the oxide film 32j. Since the electrical resistance of the oxide film 32j is large, the electrical connection between the two is improved only by bringing the protrusion 32 of the positive electrode connection member 35 into contact with the inner peripheral surface 37d of the positive electrode external terminal member 37 (contact resistance). Cannot be reduced).

  On the other hand, in the battery 1 according to the present embodiment, at least the tip portion 37n of the pointed portion 37k of the inner peripheral surface 37d of the positive electrode external terminal member 37 breaks through the oxide film 32j, and the positive electrode connection member 35 It is in a state of entering the inside of the protruding portion 32 from the outer peripheral surface 32h of the protruding portion 32 (a state of being stuck). Accordingly, at least the tip portion 37n of the pointed portion 37k of the hole inner peripheral surface 37d of the positive electrode external terminal member 37 has an internal metal 32k (oxidized) positioned radially inward of the oxide film 32j of the protruding portion 32. In contact with a part made of no aluminum). Thereby, the electrical connection between the positive electrode connection member 35 (protrusion part 32) and the positive electrode external terminal member 37 (hole inner peripheral surface 37d) can be made favorable (contact resistance is reduced).

  Further, in the battery 1 according to the present embodiment, as indicated by the reference numerals in parentheses in FIG. 5, the hole inner peripheral surface 47 d constituting the through hole 47 b (terminal through hole) of the negative electrode external terminal member 47 has the through hole 47 b. It has the pointed part 47k which makes the shape (cross-sectional V shape) sharpened toward the radial direction inner side (center side). Further, as indicated by reference numerals in parentheses in FIG. 6, at least the tip portion 47n (a portion located on the radially inner side) of the pointed portion 47k extends from the outer peripheral surface 42h of the protruding portion 42 of the negative electrode connecting member 45. In a state of entering the projecting portion 42 (a state of being pierced), the projecting portion 42 is in contact with the inner metal 42k (specifically, copper).

  Thereby, like the positive electrode side mentioned above, the protrusion part 42 of the negative electrode connection member 45 and the hole inner peripheral surface 47d of the negative electrode external terminal member 47 can be reliably connected (to ensure a stable connection state of both). The electrical connection between the protrusion 42 of the negative electrode connection member 45 and the hole inner peripheral surface 47d of the negative electrode external terminal member 47 can be improved (contact resistance can be reduced).

  In the present embodiment, a pointed portion 37k (pointed portion 47k) is formed over the entire circumference of the hole inner peripheral surface 37d of the positive electrode external terminal member 37 (hole inner peripheral surface 47d of the negative electrode external terminal member 47). Yes. More specifically, the hole inner peripheral surface 37d of the positive electrode external terminal member 37 (hole inner peripheral surface 47d of the negative electrode external terminal member 47) has an annular pointed portion 37k (pointed portion 47k) having a V-shaped cross section. ).

  Further, as shown in FIG. 5, the apex (vertex) 37m of the pointed portion 37k is located above the thickness center CT of the pressing portion 37f of the positive electrode external terminal member 37 (on the protruding tip 33 side of the protruding portion 32). doing. The apex (vertex) 47m of the pointed portion 47k is also located above the thickness center CT of the pressing portion 47f of the negative electrode external terminal member 47 (on the protruding tip portion 43 side of the protruding portion 42).

Next, a method for manufacturing the battery 1 of the present embodiment will be described.
As shown in FIG. 7, the battery case lid 15 with a terminal is produced in step S1. Specifically, first, an elongated flat plate-like lid 13 is prepared (see FIG. 3). At this time, the liquid injection port 13n of the lid 13 is not sealed by the liquid injection stopper 13m (the liquid injection stopper 13m is not attached). In addition, a positive electrode connection member 35, a positive electrode external terminal member 37, and a positive electrode fastening member 39 are prepared. Also, a negative electrode connecting member 45, a negative electrode external terminal member 47, and a negative electrode fastening member 49 are prepared. Further, two first insulating members 80 and two second insulating members 70 are prepared. At this time, the protruding tip portion 33 of the positive electrode connecting member 35 and the protruding tip portion 43 of the negative electrode connecting member 45 are in a cylindrical shape because they are before being crimped (see FIG. 9).

  Next, these members are assembled. Specifically, first, as shown in FIG. 8, in step S <b> 11 (positive first side caulking step), the protrusion 32 of the positive electrode connection member 35 is moved from its tip side (projection tip 33 side) to the first. 2. Insert the through hole 70b of the insulating member 70, the through hole 13h of the lid 13, the through hole 80b of the first insulating member 80, and the through hole 37b of the positive external terminal member 37 in this order (see FIG. 9). Prior to this, the head portion 39b of the positive electrode fastening member 39 is arranged in the head arrangement portion 81 of the first insulating member 80, and the shaft portion 39c of the positive electrode fastening member 39 is attached to the positive electrode external terminal member 37. It is inserted through the through hole 37c.

  Thereafter, in this state, the projecting tip portion 33 of the projecting portion 32 is crimped, and the positive external terminal member 37 is pressed downward (to the pedestal portion 31 side). Specifically, as shown in FIG. 9, by applying a caulking load F from one side (upper side in FIG. 9) to the cylindrical protruding tip 33, the protruding tip 33 is made to have an inner peripheral surface 33 g. Then, it is deformed into a disk shape while being crushed in the load direction (downward in FIG. 9) so as to be expanded (increase in diameter) in the direction from 33 to the outer peripheral surface 33h. Thereby, the positive electrode external terminal member 37 is pressed in the load direction of the caulking load F (downward in FIG. 9) by the deformed protruding tip portion 33. Thereby, as shown in FIG. 10, the second insulating member 70, the lid body 13, the first insulating member 80, and the positive electrode external terminal member 37 are narrowed between the protruding tip portion 33 and the pedestal portion 31, The second insulating member 70, the lid body 13, the first insulating member 80, and the positive external terminal member 37 are brought into a fastened state.

  Next, the process proceeds to step S12 (second positive side caulking step), and a portion (referred to as a projecting insertion portion 32b) of the projecting portion 32 located in the through hole 37b (terminal through hole) of the positive external terminal member 37 is expanded. Let the diameter. Specifically, as shown in FIG. 11, a cylindrical punch 21 having a tip part 21 b having a truncated cone shape whose diameter is reduced toward the tip side (lower side in FIG. 11) is formed from above the protruding part 32. It is driven into the projecting insertion portion 32b downward. In addition, as shown in FIG. 10, the protrusion insertion part 32b before driving the punch 21 is a solid cylindrical shape.

  More specifically, the punch 21 is driven toward the concave portion 33b located at the center of the protruding tip portion 33 of the protruding portion 32 with the central axis of the punch aligned with the central axis (axis line AX) of the protruding portion 32. Then, the punch 21 is driven into the protruding insertion portion 32b so as to expand the recess 33b. In the present embodiment, the tip 21c of the punch 21 reaches the lower surface 37j of the pressing portion 37f of the positive electrode external terminal member 37 in the axial direction of the protrusion 32 (the direction in which the axis AX extends, the vertical direction in FIG. 11). The punch 21 is driven in (until the punch 21 penetrates the protruding insertion portion 32b in the axial direction).

  Thereby, the diameter of the projecting insertion portion 32b of the projecting portion 32 is increased, and the outer peripheral surface 32h of the projecting portion 32 (specifically, the outer peripheral surface of the projecting insertion portion 32b) is expanded (moved radially outward). As a result, at least the distal end portion 37n of the pointed portion 37k of the positive electrode external terminal member 37 adjacent to the outer side in the radial direction of the protruding insertion portion 32b has an outer peripheral surface 32h (specifically, the protruding insertion portion 32b). From the outer peripheral surface) into the inside of the protrusion 32 (piercing). More specifically, as shown in FIG. 6, the tip portion 37 n of the pointed portion 37 k breaks through the oxide film 32 j of the protruding portion 32 and protrudes from the outer peripheral surface 32 h of the protruding portion 32 of the positive electrode connecting member 35. It will be in the state of getting inside (stabbed state).

  Accordingly, at least the tip portion 37n of the pointed portion 37k of the hole inner peripheral surface 37d of the positive electrode external terminal member 37 has an internal metal 32k (oxidized) positioned radially inward of the oxide film 32j of the protruding portion 32. It comes into contact with a part made of no aluminum. Thereby, the electrical connection between the positive electrode connection member 35 (protrusion part 32) and the positive electrode external terminal member 37 (hole inner peripheral surface 37d) can be made favorable (contact resistance is reduced). Thereafter, the punch 21 is removed from the protrusion 32.

  In the present embodiment, the pointed portion 37k is formed over the entire inner peripheral surface 37d of the positive electrode external terminal member 37. More specifically, the hole inner peripheral surface 37d of the positive electrode external terminal member 37 is formed by an annular pointed portion 37k having a V-shaped cross section. For this reason, even when the protrusion part 32 of the positive electrode connection member 35 and the hole inner peripheral surface 37d (through hole 37b) of the positive electrode external terminal member 37 are misaligned (the center axes of each other are misaligned), The distal end portion 37n can surely enter (pierce) the inside of the protruding portion 32. The same applies to the negative electrode side described later.

  By the way, the tip 21b of the punch 21 has a truncated cone shape whose diameter is reduced toward the tip (lower side in FIG. 11). For this reason, in step S12 (positive electrode side second caulking step), the portion located on the upper side of the protruding insertion portion 32b is enlarged radially outward. Accordingly, the tip portion 37n of the pointed portion 37k is positioned on the protruding portion 32 as the apex portion 37m of the pointed portion 37k is located on the upper side of the pressing portion 37f (hole inner peripheral surface 37d) of the positive electrode external terminal member 37. It is possible to penetrate deeply into the inside (pierce), and to improve the electrical connection between the positive electrode connecting member 35 (projecting portion 32) and the positive electrode external terminal member 37 (inner peripheral surface 37d) (reducing contact resistance). Be possible).

  On the other hand, in this embodiment, as shown in FIG. 5, the apex portion 37m of the pointed portion 37k is located above the thickness center CT of the pressing portion 37f of the positive electrode external terminal member 37 (the protruding tip portion 33 of the protruding portion 32). Side). For this reason, the tip part 37n of the pointed part 37k can be deeply penetrated (pierced) into the protrusion 32, and the positive electrode connection member 35 (protrusion 32) and the positive electrode external terminal member 37 (hole inner peripheral surface 37d). ) Can be improved (contact resistance can be reduced). The same applies to the negative electrode side described later.

Further, the negative electrode side (the negative electrode connecting member 45, the negative electrode external terminal member 47, and the negative electrode fastening member 49) is also assembled in the same manner as the positive electrode side described above.
Specifically, in step S13 (negative electrode first caulking step), the projecting portion 42 of the negative electrode connecting member 45 is connected to the through hole 70b of the second insulating member 70 and the lid from its distal end side (projecting distal end portion 43 side). The through hole 13k of the body 13, the through hole 80b of the first insulating member 80, and the through hole 47b of the negative electrode external terminal member 47 are inserted in this order (see FIG. 9). Prior to this, the head portion 49b of the negative electrode fastening member 49 is arranged in the head arrangement portion 81 of the first insulating member 80, and the shaft portion 49c of the negative electrode fastening member 49 is arranged in the negative electrode external terminal member 47. It is inserted through the through hole 47c.

  Thereafter, in this state, the projecting tip portion 43 of the projecting portion 42 is crimped, and the negative external terminal member 47 is pressed downward (to the pedestal portion 41 side). Specifically, by applying a caulking load F from one side (upper side in FIG. 9) to the cylindrical protruding tip portion 43, the protruding tip portion 43 is directed from the inner peripheral surface 43g toward the outer peripheral surface 43h. It is deformed into a disk shape while being crushed in the load direction (downward in FIG. 9) so as to be expanded (expanded in diameter). Thereby, the negative external terminal member 47 is pressed in the load direction of the caulking load F (downward in FIG. 9) by the deformed protruding tip portion 43. Thereby, as shown in FIG. 10, the second insulating member 70, the lid body 13, the first insulating member 80, and the negative electrode external terminal member 47 are narrowed between the protruding tip portion 43 and the pedestal portion 41, The second insulating member 70, the lid body 13, the first insulating member 80, and the negative electrode external terminal member 47 are in a fastened state.

  Next, it progresses to step S14 (negative electrode side 2nd crimping process), and the site | part located in the through-hole 47b (terminal through-hole) of the negative electrode external terminal member 47 among the protrusion parts 42 similarly to above-mentioned step S12. The diameter of the projecting insertion portion 42b is increased. Specifically, as shown in FIG. 11, the columnar punch 21 is driven into the protruding insertion portion 42b from the upper side to the lower side of the protruding portion 42, as in step S12 described above. In addition, as shown in FIG. 10, the protrusion insertion part 42b before driving the punch 21 is a solid cylindrical shape.

  Thereby, the diameter of the protruding insertion portion 42b of the protruding portion 42 is increased, and the outer peripheral surface 42h of the protruding portion 42 (specifically, the outer peripheral surface of the protruding insertion portion 42b) is increased in diameter (moved radially outward). Accordingly, at least the tip portion 47n of the pointed portion 47k of the negative electrode external terminal member 47 adjacent to the radially outer side of the protruding insertion portion 42b has an outer peripheral surface 42h (specifically, the protruding insertion portion 42b). From the outer peripheral surface) into the inside of the protruding portion 42 (piercing). More specifically, as shown in FIG. 6, the tip portion 47 n of the pointed portion 47 k breaks through the oxide film 42 j of the protruding portion 42 and protrudes from the outer peripheral surface 42 h of the protruding portion 42 of the negative electrode connecting member 45. It will be in the state of getting inside (stabbed state).

  Therefore, at least the tip portion 47n of the pointed portion 47k of the hole inner peripheral surface 47d of the negative electrode external terminal member 47 has an inner metal 42k (oxidized) positioned radially inward of the oxide film 42j of the protruding portion 42. It will be in the state which touched the part which does not have copper. Thereby, the electrical connection between the negative electrode connection member 45 (protrusion part 42) and the negative electrode external terminal member 47 (hole inner peripheral surface 47d) can be made favorable (contact resistance is reduced). Thereafter, the punch 21 is removed from the protrusion 42. Thereby, the battery case cover 15 with a terminal is completed.

  Next, returning to the main routine of FIG. 7, in step S2 (electrode body manufacturing process), the electrode body 50 is manufactured. Specifically, the sheet-like separator 57 is interposed between the sheet-like positive electrode plate 55 and the sheet-like negative electrode plate 56, and these are wound to form the flat wound electrode body 50. However, the positive electrode plate 55 and the negative electrode plate 56 are arranged so that the positive electrode winding portion 55b of the positive electrode plate 55 and the negative electrode winding portion 56b of the negative electrode plate 56 are located on opposite sides in the width direction (left-right direction in FIG. 1). And the separator 57 is wound.

  Next, the process proceeds to step S <b> 3 (welding process), and the electrode body connection portion 34 of the positive electrode connection member 35 is welded to the positive electrode winding portion 55 b of the electrode body 50. Further, the electrode body connection portion 44 of the negative electrode connection member 45 is welded to the negative electrode winding portion 56 b of the electrode body 50. Thus, the positive electrode terminal member 30 and the positive electrode plate 55 are electrically connected, the negative electrode terminal member 40 and the negative electrode plate 56 are electrically connected, and the terminal-attached battery case lid 15 and the electrode body 50 are connected. Integrate.

Next, the process proceeds to step S4 (accommodating step), and the electrode body 50 is accommodated inside the battery case main body 11, while the lid 11 closes the opening 11d of the battery case main body 11 (see FIG. 1). In this state, the lid 13 and the battery case main body 11 are joined together by welding all around.
Then, it progresses to step S5 (injection process), inject | pours electrolyte solution (not shown) in the inside of the battery case main body part 11 through the injection hole 13n of the cover body 13, and this electrolyte solution is put in the inside of the electrode body 50. Impregnate. Next, the liquid inlet 13n of the lid 13 is sealed with a liquid stopper 13m. Then, the battery 1 (refer FIG. 1) of this embodiment is completed by performing a predetermined process.

  In this embodiment, step S11 (positive first caulking process) and step S12 (positive second caulking process), and step S13 (negative first caulking process) and step S14 (negative second caulking process). Step) corresponds to the “caulking step”. Among these, step S12 (positive electrode second caulking step) and step S14 (negative electrode second caulking step) correspond to the “diameter expanding step”.

(Deformation)
Next, modifications of the present invention will be described. This modified embodiment is different from the embodiment only in the pointed portion on the inner peripheral surface of the hole of the positive electrode external terminal member and the pointed portion on the inner peripheral surface of the hole of the negative electrode external terminal member, and the others are the same. .

In the embodiment, the pointed portion 37k (over the entire circumference of the hole inner peripheral surface 37d constituting the through hole 37b of the positive electrode external terminal member 37 (hole inner peripheral surface 47d constituting the through hole 47b of the negative electrode external terminal member 47). A pointed portion 47k) was provided.
On the other hand, in this modified embodiment, as shown in FIG. 12, a hole inner peripheral surface 137d constituting the through hole 137b of the positive electrode external terminal member 137 (a hole inner peripheral surface forming the through hole 147b of the negative electrode external terminal member 147). 147d) is provided with a first pointed portion 137k1 and a second pointed portion 137k2 (first pointed portion 147k1 and second pointed portion 147k2) spaced apart in the circumferential direction.

  More specifically, as shown in FIG. 12, the positive electrode external terminal member 137 (the negative electrode external terminal member 147 is viewed in plan, passes through the center of the through hole 137b (through hole 147b), and passes through the through hole 137b (through hole 147b). ) Is divided into two, when any center line CL is drawn, both of the hole inner peripheral surface 137d (hole inner peripheral surface 147d) divided into two by the center line CL, A first cusp portion 137k1 (147k1) and a second cusp portion 137k2 (147k2) are provided so that at least a part of the first cusp portion 137k1 (147k1) or the second cusp portion 137k2 (147k2) exists. It has been.

  By providing the pointed portion at such a position, the tip end portion of the pointed portion can surely enter (pierce) the inside of the protruding portion 32 (the protruding portion 42). Specifically, even when the protrusion 32 of the positive electrode connection member 35 and the hole inner peripheral surface 137d (through hole 137b) of the positive electrode external terminal member 137 are misaligned in step S12 (the center axes of the positive electrode connection member 35 are misaligned). The tip of the first cusp 137k1 (147k1) or the second cusp 137k2 (147k2) can surely enter (pierce) the protrusion 32.

  In FIG. 12, when the center line CL that divides the through hole 137b (through hole 147b) into two in the vertical direction is drawn as the center line CL, the hole inner peripheral surface 137d (hole Two ranges of the inner peripheral surface 147d) are indicated by D and E. In this example, the first pointed portion 137k1 (147k1) exists in the range E, and the second pointed portion 137k2 (147k2) exists in the range D.

  In the above, the present invention has been described with reference to the embodiments and modifications. However, the present invention is not limited to the above-described embodiments and the like, and can be applied with appropriate modifications without departing from the gist thereof. Not too long.

  For example, in the embodiment, step S12 (positive electrode second caulking step) is performed after step S11 (positive electrode first caulking step), but step S12 (positive electrode first caulking step) is performed before step S11 (positive electrode first caulking step). You may make it perform a 2nd crimping process. Moreover, you may make it perform step S11 (positive electrode 1st crimping process) and step S12 (positive electrode 2nd crimping process) simultaneously. The same applies to step S13 (negative electrode first caulking step) and step S14 (negative electrode second caulking step).

  In the embodiment, the present invention is applied to both the positive electrode connecting member 35 and the positive electrode external terminal member 37 and the negative electrode connecting member 45 and the negative electrode external terminal member 47. That is, the pointed portion 37k is provided on the inner peripheral surface 37d of the positive electrode external terminal member 37, and the pointed portion 47k is also provided on the inner peripheral surface 47d of the negative electrode external terminal member 47. And at least the tip part 37n (47n) of the pointed part 37k (47k) enters the inside of the protruding part 32 of the positive electrode connecting member 35 (the protruding part 42 of the negative electrode connecting member 45) (a state where it is pierced). It was.

  However, the present invention may be applied to any one of the positive electrode connection member 35, the positive electrode external terminal member 37, the negative electrode connection member 45, and the negative electrode external terminal member 47. For example, it may be applied only to the positive electrode connection member 35 and the positive electrode external terminal member 37. That is, the pointed portion 37k is provided only on the hole inner peripheral surface 37d of the positive electrode external terminal member 37, and at least the tip portion 37n of the pointed portion 37k enters the inside of the protruding portion 32 of the positive electrode connecting member 35 ( It may be in a state of being pierced).

DESCRIPTION OF SYMBOLS 1 Battery 10 Battery case 11 Battery case main-body part 13 Cover body 13h, 13k Through-hole (lid through-hole)
15 Battery Case Cover with Terminal 21 Punch 32, 42 Protruding Part 32b, 42b Protruding Insertion Part 32h, 42h Peripheral Surface 32j, 42j Oxide Film 33, 43 Protruding Tip 34, 44 Electrode Body Connecting Part 35 Positive Electrode Connecting Member ( Electrode connection member)
37, 137 Positive external terminal member (external terminal member)
37b, 47b, 137b, 147b Through hole (terminal through hole)
37d, 47d, 137d, 147d Hole inner peripheral surface 37k, 47k Pointed portion 37n, 47n Pointed end portion 45 Negative electrode connecting member (electrode connecting member)
47,147 Negative external terminal member (external terminal member)
50 Electrode body 55 Positive electrode 56 Negative electrode 57 Separator 70 Second insulating member 80 First insulating member 137k1, 147k1 First pointed portion 137k2, 147k2 Second pointed portion

Claims (1)

An electrode body having a positive electrode and a negative electrode;
A battery case that houses the electrode body;
A metal electrode connecting member having an electrode body connecting portion located in the battery case and connected to the electrode body, and a columnar protruding portion protruding to the outside of the battery case;
An external terminal member located outside the battery case, and a metal external terminal member having a terminal through-hole through which the protruding portion of the electrode connection member is inserted, and
In the battery in which the external terminal member and the electrode connecting member are fixed to the battery case in a state where the protrusion is inserted into the terminal through hole and the protrusion is caulked and deformed,
The hole inner peripheral surface of the external terminal member constituting the terminal through hole has a pointed portion that has a pointed shape toward the radially inner side of the terminal through hole,
The battery which is contacting the inside of the said protrusion part in the state which at least the front-end | tip part among the said pointed parts entered the inside of the said protrusion part from the outer peripheral surface of the said protrusion part.

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