JP2009295418A5 - - Google Patents

Description

Sealed battery manufacturing method and sealed battery

The present invention allows a shaft provided on the lower surface side of the head of the output terminal to be inserted into a through hole formed in a sealing plate that closes the upper surface of the opening of the battery can with an insulating packing interposed therebetween, and below the sealing plate. An output terminal is arranged by placing a pressing plate on the side through an insulating material, inserting the shaft portion of the output terminal into the insertion hole between the insulating material and the pressing plate, and caulking the output terminal with a compressive force in the vertical direction. Further, the present invention relates to a method for manufacturing a sealed battery in which an insulating packing, an insulating material, and a pressing plate are fixed to a sealing plate.
The present invention also provides a bottomed cylindrical battery can having a horizontally long opening on the upper surface, an electrode body and a non-aqueous electrolyte accommodated in the battery can, and the upper surface of the opening of the battery can is closed and sealed. The present invention relates to a sealed battery comprising a horizontally long sealing plate and a synthetic resin insulator disposed inside the sealing plate, wherein the sealing plate is welded to the opening periphery of the battery can by a laser.

  Examples of the sealed battery include those shown in Patent Documents 1 and 2, and the output terminal 15 is caulked as shown in FIG. 7, for example. First, the shaft portion 23 of the output terminal 15 is inserted into the through hole 14 of the sealing plate 3 with the insulating packing 12 interposed, and the shaft portion 23 of the output terminal 15 is inserted into the insertion hole of the insulating material 13 and the holding plate 16. 32 and 33 are inserted. In FIG. 7, the top and bottom are reversed in accordance with the actual caulking work.

  In this state, the punch 40 for applying a compressive force in the vertical direction to the output terminal 15 is lowered to push the lower end surface 23a of the output terminal 15 downward, and the mountain-shaped bulging portion 40a of the punch 40 is The output terminal 15 is engaged with a recess 25 that is recessed in the lower end surface 23 a of the output terminal 15.

  As a result, at the lower end portion 23 c of the output terminal 15, a portion 41 that protrudes below the insertion hole 33 (upper side in FIG. 7) of the holding plate 16 extends outward in the radial direction of the insertion hole 33. The insulating packing 12, the pressing plate 16, the insulating material 13, and the sealing plate 3 are sandwiched between the expanded projecting portion 41 of the output terminal 15 and the head portion (not shown) of the output terminal 15, thereby insulating the output terminal 15. The packing 12, the pressing plate 16, and the insulating material 13 are fixed to the sealing plate 3.

Japanese Patent Laying-Open No. 2005-129488 (FIG. 1) JP 2003-045407 A (FIG. 1)

  In the caulking process, when the protruding portion 41 of the output terminal 15 is spread outward in the radial direction, the shaft portion 23 portion of the output terminal 15 which is the upper side (lower side in FIG. 7) of the protruding portion 41 is Then, it is bent and deformed in the axial direction of the output terminal 15. For this reason, a gap S is generated between the shaft portion 23 of the output terminal 15 and the inner surface of the insertion hole 33 of the pressing plate 16 and between the output terminal 15 and the insulating packing 12, and accordingly, the output terminal 15 is insulated from the output terminal 15. The sealing performance with the packing 12 is insufficient. As a result, the electrolyte in the battery may leak out of the battery through the gap S.

  Further, in the punch 40, the mountain-shaped bulge portion 40a must be formed, and the shape of the punch 40 is complicated by that amount, and it takes time and money to manufacture the punch 40. become.

  The present invention has been made in order to solve the problems of the above-described method for manufacturing a sealed battery, and provides a method for manufacturing a sealed battery that can maintain high sealing performance between an output terminal and a sealing plate. The purpose is to provide. In addition, an object of the present invention is to provide a method for manufacturing a sealed battery in which a caulking punch can be formed into a simple shape.

In the present invention, a cylindrical shaft portion 23 provided on the lower surface side of the head 21 of the output terminal 15 is interposed in an insulating packing 12 in a circular through hole 14 formed in the sealing plate 3 that closes the upper surface of the opening of the battery can 1. The presser plate 16 is disposed below the sealing plate 3 with the insulating material 13 interposed therebetween, and the shaft of the output terminal 15 is inserted into the insertion holes 32 and 33 between the insulating material 13 and the presser plate 16. A sealed battery formed by fixing the output terminal 15, the insulating packing 12, the insulating material 13, and the pressing plate 16 to the sealing plate 3 by inserting the portion 23 and caulking the output terminal 15 with a compressive force in the vertical direction. For manufacturing methods. With the lower end portion 23c of the shaft portion 23 of the output terminal 15 protruding below the presser plate 16, the lower end portion 23c of the shaft portion 23 of the output terminal 15 is compressed by the vertical compression force, and the upper and lower intermediate portions thereof are the shaft. The lower end portion 23c of the shaft portion 23 of the output terminal 15 is squeezed up and down so as to swell outward in the radial direction of the portion 23, and protrudes outward in the radial direction of the insertion hole 33 of the pressing plate 16 By pressing the pressing plate 16 against the sealing plate 3 through the insulating material 13 at the protruding portion 37, the insulating packing 12, the sealing plate 3, the insulating material 13, and the pressing plate 16 are connected to the protruding portion 37 of the output terminal 15. It is characterized by being sandwiched between the head 21.
The output terminal 15 here includes a negative terminal and a positive terminal.

  In a free state before caulking, a recess 25 is formed in the center of the lower end surface 23a of the shaft portion 23 of the output terminal 15, and an outer peripheral edge 23b of the lower end surface 23a of the shaft portion 23 of the output terminal 15 is circular in the radial direction. The punch 36 that is curved in an arc shape and applies a compressive force in the vertical direction to the output terminal 15 has a flat pressing surface 36 a that presses against the lower end surface 23 a of the shaft portion 23 of the output terminal 15. Is pressed against the lower end surface 23a of the shaft portion 23 of the output terminal 15 in the free state before caulking and the outer peripheral edge 23b of the lower end surface 23a, so that the outer peripheral edge 23b of the lower end surface 23a is The lower end portion 23c of the shaft portion 23 of the output terminal 15 may be crushed up and down by being pushed toward the shaft center side of the shaft portion 23 of the output terminal 15 so as to slide on the pressing surface 36a.

The present invention covers a bottomed cylindrical battery can 1 having a horizontally long opening on its upper surface, an electrode body 2 and a non-aqueous electrolyte accommodated in the battery can 1, and the upper surface of the opening of the battery can 1. The sealing plate 3 is provided with a horizontally long sealing plate 3 that is sealed with a plastic resin insulator 5 disposed inside the sealing plate 3, and the sealing plate 3 is welded to the periphery of the opening of the battery can 1 by a laser. Sealed battery. The sealing plate 3 is formed by a cleavage vent 9, a through hole 14, and a liquid injection hole 10 for injecting the non-aqueous electrolyte, and the liquid injection hole 10 is closed with a sealing plug 11. Yes. A negative electrode terminal 15 is inserted through the through-hole 14 with an insulating packing 12 interposed therebetween, and an insulating material 13 and a pressing plate 16 are arranged on the lower side of the sealing plate 3 so as to overlap each other. The plate 16 is electrically connected to the negative electrode terminal 15 by contacting the lower end of the negative electrode terminal 15. The lower end portion of the shaft portion of the negative electrode terminal 15 is bent at the upper and lower intermediate portions, and a protruding portion 37 is formed on the outer side in the radial direction of the insertion hole 33 below the insertion hole 33 of the pressing plate 16. The insulating packing 12, the sealing plate 3, the insulating material 13, and the pressing plate 16 are integrated from the protruding portion 37 of the negative electrode terminal 15.

The negative electrode terminal 15 includes a horizontally elongated flat rectangular head portion 21, a step portion 22 projecting downward at the center of the lower surface of the head portion 21, and a lower surface side of the head portion 21 via the step portion 22. It has a columnar shaft portion 23 extending downward, and a columnar concave portion 25 that is recessed and formed in the center of the lower end surface 23a of the shaft portion 23 in a free state before caulking.
The thickness of the peripheral wall of the concave portion 25 is preferably thinner than the thickness of other portions.

  In the manufacturing method of the sealed battery according to the present invention, the upper and lower middles of the lower end portion 23c of the shaft portion 23 of the output terminal 15 swell outward in the radial direction of the shaft portion 23 so that the shaft portion 23 of the output terminal 15 Since the lower end part 23c is crushed up and down, the shaft part 23 part of the output terminal 15 other than the lower end part 23c also tends to bulge outward in the radial direction. The shaft portion 23 of the output terminal 15 is strongly pressed against the inner surface side of the insertion hole 33 of the pressing plate 16 and the insertion hole 32 of the insulating material 13, and the inner surface of the through hole 14 of the sealing plate 3 through the insulating packing 12. Strongly pressed against.

  As a result, the sealing performance between the output terminal 15 and the through hole 14 of the sealing plate 3 can be reliably obtained, and the sealing performance between the output terminal 15 and the pressing plate 16 and the insertion hole of the insulating material 13 can also be obtained. . Thus, it is possible to reliably prevent the electrolyte in the battery can 1 from leaking out of the battery through the output terminal 15 and the through hole 14 of the sealing plate 3.

  The portion 37 that protrudes outward in the radial direction of the insertion hole 33 of the pressing plate 16 presses the pressing plate 16 against the sealing plate 3 through the insulating material 13, so that the pressing plate 16 and the insulating material 13 are reliably attached to the sealing plate 3. Fixed.

  When the concave portion 25 is formed in the center of the lower end surface 23a of the shaft portion 23 of the output terminal 15, the lower end portion 23c of the shaft portion 23 of the output terminal 15 can be easily crushed by the vertical compression force. In addition, since the pressing surface 36a of the punch 36 that applies a compressive force in the vertical direction to the output terminal 15 is formed in a flat shape, the shape of the punch 36 is simplified correspondingly, and the labor and cost of manufacturing the punch 36 are reduced. Can be reduced. Since the outer peripheral edge 23b of the lower end surface 23a of the shaft portion 23 of the output terminal 15 is curved in an arc shape in the radial direction, the outer peripheral edge 23b slides on the pressing surface 36a of the punch 36 along the curve. Then, the output terminal 15 is pushed toward the axial center side of the shaft portion 23. Thus, the lower end portion 23c of the shaft portion 23 can be crushed in a state where the upper and lower middle portions of the lower end portion 23c of the shaft portion 23 of the output terminal 15 are surely expanded outward in the radial direction of the shaft portion 23. it can.

  As shown in FIG. 3, the sealed battery according to the present invention includes a bottomed cylindrical battery can 1 having a horizontally long opening on an upper surface, an electrode body 2 accommodated in the battery can 1, and a nonaqueous electrolyte. And a horizontally long sealing plate 3 that closes and seals the upper surface of the opening of the battery can 1, and a synthetic resin insulator 5 disposed inside the sealing plate 3. The battery can 1 has a left-right width dimension of 34 mm, a vertical height dimension of 46 mm, and a front-rear thickness dimension of 4 mm. A battery case 6 is formed by the battery can 1 and the sealing plate 3.

  The battery can 1 is formed by deep drawing a plate made of aluminum or an alloy thereof, and the sealing plate 3 is formed by pressing a plate such as an aluminum alloy. Then, the sealing plate 3 is seam welded to the opening periphery of the battery can 1 by a laser. The insulator 5 is disposed on the lower side of the sealing plate 3. The electrode body 2 is formed by winding a strip-shaped positive electrode and a strip-shaped negative electrode in a spiral shape with a strip-shaped separator interposed therebetween, and is formed in a flat shape as a whole.

  A cleavage vent 9 is formed on the left side of the sealing plate 3. The cleavage vent 9 is cleaved when the battery internal pressure abnormally rises to release the battery internal pressure. A liquid injection hole 10 for injecting a non-aqueous electrolyte into the battery case 6 is formed on the right side of the sealing plate 3, and the liquid injection hole 10 after the injection of the non-aqueous electrolyte is closed with a sealing plug 11. It is peeled off and sealed by laser.

  As shown in FIGS. 1 and 2, a circular through hole 14 is formed in a vertically penetrating manner at the center in the left-right direction of the sealing plate 3, and a negative electrode terminal (output terminal) 15 is provided in the through hole 14. The insulating packing 12 is inserted therethrough. On the lower side of the sealing plate 3, an insulating material 13 and a pressing plate 16 are arranged one above the other. The pressing plate 16 is electrically connected to the negative electrode terminal 15 by contacting the lower end portion of the negative electrode terminal 15. The insulating packing 12 and the insulating material 13 are made of a synthetic resin molded product having an insulating property such as polypropylene, and the pressing plate 16 is made of a nickel plate that is horizontally long. The negative electrode terminal 15 is insulated from the sealing plate 3 by the insulating packing 12.

  The insulating material 13 extends from the negative electrode terminal 15 side toward the cleavage vent 9 side, and the pressing plate 16 extends in the lateral direction along the sealing plate 3 from the negative electrode terminal 15 side toward the cleavage vent 9 side. . That is, the insulating material 13 is interposed between the pressing plate 16 and the sealing plate 3, and the pressing plate 16 is insulated from the sealing plate 3 by the insulating material 13. The negative terminal 15, the insulating packing 12, the insulating material 13, and the pressing plate 16 are integrally fixed to the sealing plate 3 by caulking the negative terminal 15 in the vertical direction.

  The lower end of the negative electrode current collector lead 18 shown in FIG. 3 is connected to the negative electrode of the electrode body 2, and the upper end of the negative electrode current collector lead 18 is welded to the lower surface of the holding plate 16. The lower end of the positive electrode current collecting lead 19 is connected to the positive electrode of the electrode body 2, and the upper end of the positive electrode current collecting lead 19 is in the space between the negative electrode terminal 15 and the liquid injection hole 10 on the lower surface of the sealing plate 3. Welded. Thus, the negative electrode terminal 15 has the same potential as the negative electrode of the electrode body 2, and the sealing plate 3 and the battery can 1 have the same potential as the positive electrode of the electrode body 2.

  As shown in FIGS. 2 and 4, the negative electrode terminal 15 includes a horizontally long flat rectangular head portion 21 exposed on the upper surface of the insulating packing 12, and a step portion 22 that protrudes downward at the center of the lower surface of the head portion 21. And a cylindrical shaft portion 23 extending downward from the lower surface side of the head portion 21 through the stepped portion 22, and a recess in the center of the lower end surface 23a of the shaft portion 23 in a free state before caulking. It has the cylindrical-shaped recessed part 25 (FIG. 4) formed. The negative electrode terminal 15 is made of an iron material or the like whose surface is plated with copper nickel. As shown in FIG. 4, the outer peripheral edge 23 b of the lower end surface 23 a of the shaft portion 23 of the negative electrode terminal 15 is curved in an arc shape in the radial direction.

  The lower end portion 23c of the shaft portion 23 of the negative electrode terminal 15 whose thickness of the peripheral wall is reduced by forming the concave portion 25 is obtained by assembling the negative electrode terminal 15, the insulating packing 12, the insulating material 13, and the pressing plate 16 to the sealing plate 3. At this time, as shown in FIG. 5, the presser plate 16 is positioned substantially outward (upper side in FIG. 5).

  As shown in FIGS. 2 and 4, the insulating packing 12 includes a horizontally long flange portion 27 received by a recess 26 provided at the center of the upper surface of the sealing plate 3 and an insertion hole 30 through which the shaft portion 23 of the negative electrode terminal 15 is inserted. And a cylindrical tube portion 28 provided with the. A receiving seat 29 for receiving the head portion 21 of the negative electrode terminal 15 is formed on the upper surface of the flange portion 27 of the insulating packing 12. The upper portion of the insertion hole 30 of the insulating packing 12 extends to the center of the seat 29 of the flange portion 27. The diameter of the upper part of the insertion hole 30 is large, and the step part 22 of the negative electrode terminal 15 engages with the upper part of the insertion hole 30 (state of FIG. 2). The through hole 14 of the sealing plate 3 is provided at the center of the lower surface of the recess 26.

  A circular insertion hole 32 through which the shaft portion 23 of the negative electrode terminal 15 and the lower end portion of the cylindrical portion 28 of the insulating packing 12 are inserted is formed in the insulating material 13, and the shaft portion 23 of the negative electrode terminal 15 is formed in the holding plate 16. A circular insertion hole 33 to be inserted is formed.

  The negative electrode terminal 15, the insulating packing 12, the insulating material 13, and the pressing plate 16 are caulked and fixed to the sealing plate 3 using a die 35 and a punch 36 for compressing the negative electrode terminal 15 shown in FIG. . That is, first, the head of the negative electrode terminal 15 is placed on the flat upper surface of the die 35 with the top of the negative electrode terminal 15 reversed (state of FIG. 5). In this state, the shaft portion 23 of the negative electrode terminal 15 is inserted into the insertion hole 30 of the insulating packing 12, and the cylindrical portion 28 of the insulating packing 12 is inserted into the through hole 14 of the sealing plate 3.

  Next, the cylindrical portion 28 of the insulating packing 12 and the shaft portion 23 of the negative electrode terminal 15 projecting outward (upward in FIG. 5) of the sealing plate 3 are inserted into the insertion hole 32 of the insulating material 13 and the insulation thereof is performed. The shaft portion 23 of the negative electrode terminal 15 protruding outward of the material 13 is inserted into the insertion hole 33 of the pressing plate 16. At this time, the lower end portion 23 c of the shaft portion 23 of the negative electrode terminal 15 protrudes outward of the pressing plate 16.

  When the punch 36 is lowered in this state, the flat pressing surface 36 a of the punch 36 comes into contact with the lower end surface 23 a (see FIG. 4) of the shaft portion 23 of the negative electrode terminal 15. By lowering the punch 36 as it is, the pressing surface 36 a of the punch 36 also presses against the outer peripheral edge 23 b at the lower end of the shaft portion 23 of the negative electrode terminal 15, and the curved outer peripheral edge 23 b becomes the pressing surface 36 a of the punch 36. Is pushed into the axial center side of the shaft portion 23. Thus, as shown in FIG. 6A, the lower end 23c of the shaft portion 23 of the negative electrode terminal 15 is curved so that the upper and lower intermediate portions swell outward, and as shown in FIG. It bends at the upper and lower middle part and is crushed up and down.

  As a result, the crushed lower end portion 23c of the negative electrode terminal 15 protrudes outwardly in the radial direction of the insertion hole 33 below the insertion hole 33 of the pressing plate 16, as shown in FIGS. The pressing plate 16 is pressed against the sealing plate 3 by the protruding portion 37. As a result, the insulating packing 12, the sealing plate 3, the insulating material 13, and the pressing plate 16 are sandwiched between the protruding portion of the negative electrode terminal 15 and the head 21, and the negative electrode terminal 15, the insulating packing 12, and the insulating material 13 are The pressing plate 16 and the sealing plate 3 are integrated.

  Further, due to the compressive force in the vertical direction by the punch 36, the shaft portion 23 of the negative electrode terminal 15 is slightly contracted in the vertical direction while slightly expanding outward in the radial direction. Thus, the outer peripheral side surface of the shaft portion 23 pushes the cylindrical portion 28 of the insulating packing 12 toward the inner surface side of the through hole 14 of the sealing plate 3, and the shaft portion 23 of the negative electrode terminal 15, the cylindrical portion 28 of the insulating packing 12, and The inner surface of the through hole 14 of the sealing plate 3 and the cylindrical portion 28 of the insulating packing 12 are firmly attached. That is, the space between the shaft portion 23 of the negative electrode terminal 15 and the inner surface of the through hole 14 of the sealing plate 3 is reliably sealed by the insulating packing 12.

  When assembling the battery, after the electrode body 2 and the insulator 5 are accommodated in the battery can 1, the sealing plate 3 in which the negative electrode terminal 15, the insulating packing 12, the insulating plate 13, and the pressing plate 16 are caulked and fixed is used. On the other hand, the negative electrode current collecting lead 18 of the electrode body 2 is welded to the holding plate 16, and the positive electrode current collecting lead 19 of the electrode body 2 is welded to the sealing plate 3. Next, after the sealing plate 3 is seam welded to the periphery of the opening of the battery can 1, the inside of the battery can 1 is vacuumed and the nonaqueous electrolyte is injected from the liquid injection hole 10.

  After completion of the injection of the non-aqueous electrolyte, the sealing plug 11 is press-fitted into the liquid injection hole 10, and the sealing plug 11 is laser welded to the peripheral edge of the liquid injection hole 10 of the sealing plate 3 (state of FIG. 3). Thus, the liquid injection hole 10 is sealed with the sealing plug 11 to complete the sealed battery of the present invention.

  In this way, the lower end portion 23c of the shaft portion 23 of the negative electrode terminal 15 is crushed up and down so that the upper and lower middle of the lower end portion 23c of the shaft portion 23 of the negative electrode terminal 15 swells outward in the radial direction of the shaft portion 23. Therefore, in that case, the shaft portion 23 portion of the negative electrode terminal 15 other than the lower end portion 23c also tends to bulge outward in the radial direction. Therefore, the shaft portion 23 of the negative electrode terminal 15 is strongly pressed against the inner surface side of the insertion hole 33 of the holding plate 16 and the insertion hole 32 of the insulating material 13, and the through hole 14 of the sealing plate 3 is interposed via the insulating packing 12. Strongly pressed against the inner surface.

  Thereby, the sealing performance between the negative electrode terminal 15 and the through hole 14 of the sealing plate 3 can be reliably obtained, and the sealing performance between the negative electrode terminal 15 and the pressing plate 16 and the insertion hole of the insulating material 13 can also be obtained. . As a result, it is possible to reliably prevent the electrolyte in the battery can 1 from leaking out of the battery through the space between the negative electrode terminal 15 and the through hole 14 of the sealing plate 3.

It is an expanded sectional view of an important section of a sealed type battery concerning the present invention. It is the sectional view on the AA line of FIG. It is a vertical front view of a sealed battery. It is a disassembled perspective view of the principal part of a sealed battery. It is a longitudinal cross-sectional view which shows the crimping process of a negative electrode terminal. (A) is the longitudinal cross-sectional view which shows completion of the caulking process of a negative electrode terminal, (b) is completion of the caulking process of a negative electrode terminal. It is a longitudinal cross-sectional view which shows the crimping process of the conventional negative electrode terminal.

DESCRIPTION OF SYMBOLS 1 Battery can 3 Sealing plate 12 Insulation packing 13 Insulation material 14 Through-hole 15 Negative electrode terminal 16 Press plate 21 Head 23 Shaft part 23a Lower end surface 23b Outer peripheral edge 23c Lower end part 25 Recess 32 * 33 Insertion hole 36 Punch 36a Pressing surface 37 Extrusion portion

Claims (5)

The cylindrical plate provided on the lower surface side of the head of the output terminal is inserted into the circular through hole formed in the sealing plate that closes the upper surface of the opening of the battery can with the insulating packing interposed therebetween, and the sealing plate A pressing plate is arranged on the lower side through an insulating material, and the shaft portion of the output terminal is inserted into the insertion hole between the insulating material and the pressing plate, and the output terminal is caulked with a compressive force in the vertical direction. In the manufacturing method of the sealed battery formed by fixing the output terminal, the insulating packing, the insulating material, and the pressing plate to the sealing plate,
With the lower end portion of the shaft portion of the output terminal protruding below the holding plate, the lower end portion of the shaft portion of the output terminal is compressed by the vertical compression force, and the middle of the shaft portion is the diameter of the shaft portion. Squeezed up and down so as to swell outward in the direction, the lower end portion of the squeezed shaft portion of the output terminal protrudes outward in the radial direction of the insertion hole of the pressing plate, and the pressing plate at the protruding portion Is pressed against the sealing plate through the insulating material, so that the insulating packing, the sealing plate, the insulating material, and the pressing plate are sandwiched between the protruding portion of the output terminal and the head. A method for producing a sealed battery, which is characterized. A concave portion is formed in the center of the lower end surface of the shaft portion of the output terminal in a free state before caulking, and the outer peripheral edge of the lower end surface of the shaft portion of the output terminal is curved in an arc shape in the radial direction. ,
The punch that applies a compressive force in the vertical direction to the output terminal has a flat pressing surface that presses against the lower end surface of the shaft portion of the output terminal, and the pressing surface of the punch is in a free state before caulking. By pressing against the lower end surface of the shaft portion of the output terminal and the outer peripheral edge of the lower end surface, the outer peripheral edge of the lower end surface is pushed toward the shaft center side of the shaft portion so as to slide on the pressing surface of the punch. The method for manufacturing a sealed battery according to claim 1, wherein a lower end portion of the shaft portion of the output terminal is crushed up and down. A bottomed cylindrical battery can having a horizontally long opening on the upper surface, an electrode body and a non-aqueous electrolyte housed in the battery can, and a horizontally long sealing plate that closes and seals the upper surface of the opening of the battery can And a sealed battery in which the sealing plate is welded to the periphery of the opening of the battery can by a laser.
The sealing plate is formed with a cleavage vent, a through hole, and a liquid injection hole for injecting the non-aqueous electrolyte, and the liquid injection hole is closed with a sealing plug,
In the through hole, a negative electrode terminal is inserted with an insulating packing interposed therebetween, and an insulating material and a pressing plate are arranged vertically on the lower side of the sealing plate, and the pressing plate is connected to the negative electrode terminal Is in contact with the negative terminal by contacting the lower end of the
A lower end portion of the shaft portion of the negative electrode terminal is bent at an upper and lower intermediate portion to form a protruding portion on the outer side in the radial direction of the insertion hole below the insertion hole of the pressing plate, and from the protruding portion of the negative electrode terminal. The sealed battery, wherein the insulating packing, the sealing plate, the insulating material, and the pressing plate are integrated. The negative electrode terminal has a horizontally long flat rectangular head, a step protruding downward at the center of the lower surface of the head, and extends downward from the lower surface of the head via the step. 4. The sealed battery according to claim 3, further comprising: a cylindrical shaft portion to be formed; and a cylindrical recess recessed in the center of the lower end surface of the shaft portion in a free state before caulking. The sealed battery according to claim 4, wherein the thickness of the peripheral wall of the recess is thinner than the thickness of the other part.