JP5213030B2 - Sealed battery manufacturing method and sealed battery - Google Patents

Description

The present invention provides a lead body together with an insulating material at a lower end portion of an output terminal that is inserted into a through-hole of the lid with an insulating packing interposed between the output terminal and the lid, and projecting to the lower side of the lid. The present invention relates to a sealed battery manufacturing method and a sealed battery in which a current collecting lead extending from an electrode body in a battery can is connected to the lead body.

  Examples of the sealed battery include those shown in Patent Documents 1 to 3. In the sealed battery described in Patent Document 1, an output terminal is inserted into a through hole formed in a cover that closes the opening of the battery can with an insulating packing interposed therebetween, and the lower side of the cover (FIG. 2 of Patent Document 1). In this case, a lead body is attached to the lower end portion of the output terminal protruding upward) together with a film-like insulating material, and a current collecting lead extending from the electrode body in the battery can is connected to the lead body.

  Even in the sealed battery described in Patent Document 2, the output terminal is inserted into the through-hole of the lid with the insulating packing interposed, and the lead body together with the insulating material is placed at the lower end of the output terminal protruding below the lid. It is manufactured by attaching and connecting the current collecting lead of the electrode body in the battery can to the lead body. In the sealed battery described in Patent Document 3, the output terminal is inserted through the through-hole of the lid with the insulating member in which the insulating packing and the insulating material are integrated, and protrudes below the lid. The lead body integrated with the current collecting lead of the electrode body in the battery can is attached to the lower end portion of the battery can.

JP-A-8-250104 (FIG. 2) JP-A-8-329911 (FIG. 3) JP 2002-164025 A (FIG. 1-2)

  In all of the sealed batteries of Patent Documents 1 to 3, the insulating material and the lead body are produced as separate parts. For this reason, when manufacturing the battery, it is necessary to handle the insulating material and the lead body as separate components, which makes it troublesome to manage such components.

  In the sealed battery described in Patent Document 1, there is a possibility that the lead body rotates around the output terminal, and in this case, the lead body may contact the inner surface of the battery can and short-circuit. On the other hand, in the sealed battery described in Patent Document 2, a stopper for preventing the rotation of the lead body is provided at the edge of the insulating material (see FIG. 9 of Patent Document 2), but the stopper is provided. Accordingly, the width of the insulating material (the vertical width in FIG. 9 of Patent Document 2) is increased. This makes it difficult to reduce the thickness of the battery.

  Even in the sealed battery described in Patent Document 3, as shown in FIG. 2C of Patent Document 3, the right end of the support wall provided on the insulating material is the leading edge of the lead body (FIG. 2C of Patent Document 3). ) Is in contact with the lower side. This prevents rotation of the lead body. However, in order to receive the lead body at the support wall portion, the support wall portion needs to be strong, and therefore the front and rear width of the support wall portion needs to be increased to some extent. . Along with this, the front-rear width of the insulating material is increased, and it is difficult to reduce the thickness of the battery.

An object of the present invention is to reduce the labor of component management between an insulating material and a lead body, and can reliably prevent the lead body from coming into contact with the inner surface of the battery can and the like, and reduce the thickness of the battery. It is another object of the present invention to provide a sealed battery manufacturing method and a sealed battery .

  In the present invention, a through hole 25 for inserting the output terminal 12 is formed in the lid 3 that closes the opening upper surface of the horizontally long battery can 1, and the insulating packing 10 is provided between the output terminal 12 and the lid 3. The output terminal 12 is inserted into the through-hole 25 of the lid 3 in the interposed state, and the left and right horizontally elongated lead bodies 13 are attached to the lower end portion of the output terminal 12 protruding to the lower side of the lid 3 together with the resin insulating material 11. A method for manufacturing a sealed battery in which the current collector lead 9 extending from the electrode body 2 accommodated in the battery can 1 is connected to the lead body 13 is an object. The lead body 13 is formed with an insertion hole 27 through which the lower end portion of the output terminal 12 is inserted, and the insulating material 11 is integrally formed with the lead body 13. In the inner space of the mold 35 for integrally molding the insulating material 11 on the lead body 13, an engagement pin 39 that engages with the insertion hole 27 of the lead body 13 and a pair of front and rear that sandwich the lead body 13 from the front and rear. Nipping pins 41 and 41 are arranged. Then, the insertion hole 29 of the lead body 13 is engaged with the engagement pin 39 and the lead body 13 is fitted between the pair of holding pins 41 and 41 so that the lead body 13 is mounted in the inner space of the mold 35. After that, molten resin is injected into the inner space of the mold 35 to cover the insulating material 11 on the front, rear, left and right and the upper surface of the lead body 13.

An engaging protrusion 26 protrudes from the lower surface of the lid 3. When the insulating material 11 is integrally formed with the lead body 13, the engaging portion 30 with which the engaging protrusion 26 engages can be formed on the upper surface of the insulating material 11.
In addition, when the insulating material 11 is integrally formed on the lead body 13, an identification portion 31 for identifying the upper and lower sides of the insulating material 11 can be formed on the lower surface of the insulating material 11.

Further, the sealed battery according to the present invention is inserted in a battery can 1 having a horizontally long open upper surface, a lid 3 that closes the open upper surface of the battery can 1, and a through hole 25 provided in the lid 3. An output terminal 12 to be fixed, an insulating packing 10 interposed between the lid 3 and the output terminal 12, and a horizontally long lead body 13 attached to a lower end portion of the output terminal 12 protruding below the lid 3. Is provided. A current collecting lead 9 extending from the electrode body 2 accommodated in the battery can 1 is connected to the lead body 13. The lead body 13 is formed with an insertion hole 27 through which the lower end portion of the output terminal 12 is inserted. The lead body 13 is integrally formed with the insulating material 11 covering the upper surface and the left and right side surfaces of the lead body 13. It is characterized by being.

  In the present invention, since the lead body 13 and the insulating material 11 are integrated, the number of parts in manufacturing the battery can be reduced as compared with the case where the lead body 13 and the insulating material 11 are separated. It is possible to reduce the time and labor of parts management at the time of manufacturing the battery. Further, for example, even if the lead body 13 rotates around the output terminal 12, the lead body 13 contacts the inner surface of the battery can 1 and is short-circuited by the insulating material 11 that rotates integrally with the lead body 13. Is reliably prevented.

  An engagement pin 39 that engages with the insertion hole 27 of the lead body 13 and a pair of sandwiching pins that sandwich the lead body 13 from the front and rear in an internal space of a mold 35 for integrally molding the insulating material 11 on the lead body 13. Since 41 and 41 are provided, the sliding movement of the lead body 13 in the lateral direction is restricted by the engagement of the engagement pin 39 and the insertion hole 27 of the lead body 13 in the mold 35. In addition, the rotation of the lead body 13 around the engaging pin 39 is restricted by the pinching pins 41 and 41. That is, the lead body 13 is reliably positioned in the mold 35 by the engagement pin 39 and the front and rear clamping pins 41 and 41. This prevents the lead body 13 from moving in the mold 35 so that the lead body 13 contacts the front, back, left and right inner surfaces of the inner space of the mold 35 and the insulating material 11 is not molded at the contact location. it can. That is, the front, rear, left and right of the lead body 13 can be reliably covered with the insulating material 11.

  In addition, since only two clamping pins 41 and 41 are in contact with the front and rear, left and right inner surfaces of the lead body 13, two locations on the front and rear, left and right inner surfaces of the lead body 13 that are not covered with the insulating material 11 due to the positioning are provided. Can only be suppressed. That is, the exposed portions of the lead body 13 can be minimized at the front, rear, left and right of the lead body 13, and the front, rear, left and right of the lead body 13 can be more reliably prevented from coming into contact with the inner surface of the battery can 1 and the like.

  The insulating material 11 only needs to cover the lead body 13, and does not aim to prevent the lead body 13 from rotating, so that strength is not required. Therefore, the front and rear, left and right thicknesses of the insulating material 11 can be reduced, and the front and rear, left and right widths of the integrally formed body of the insulating material 11 and the lead body 13 can be reduced. Moreover, for example, when the insulating material 11 and the lead body 13 are formed as separate single bodies and these are assembled, the lead body 13 is fitted into the recess formed in the lower surface of the insulating material 11. It is necessary to provide a gap between the inner surface of the concave portion of the insulating material 11 and the lead body 13 in consideration of manufacturing errors. In the present invention, it is not necessary to provide the gap by integrally forming the insulating material 11 and the lead body 13, and this also makes it possible to reduce the width of the integrally formed body of the insulating material 11 and the lead body 13. Accordingly, the width of the front, rear, left and right of the battery can be reduced by that amount, and the battery can be made thinner.

  When the engaging portion 30 is formed on the upper surface of the insulating material 11, the engaging protrusion 26 of the lid 3 is engaged with the engaging portion 30 of the insulating material 11, so that the integrally formed body of the insulating material 11 and the lead body 13 is output. It is possible to prevent the terminal 12 from rotating around the shaft, and accordingly, the integrally formed body of the insulating material 11 and the lead body 13 is prevented from interfering with other members.

  If the identification part 31 is provided on the lower surface of the insulating material 11, the upper and lower sides of the integrally formed body of the lead body 13 and the insulating material 11 can be properly aligned in a parts feeder or the like based on the identification part 31. Thus, for example, when the battery is assembled by an automatic assembly machine, the integrally formed body of the lead body 13 and the insulating material 11 can be attached to the lower end portion of the output terminal 12 without making a mistake in the upper and lower sides.

  As shown in FIG. 2, the sealed battery according to the present invention includes a bottomed cylindrical battery can 1 having a horizontally long opening on the upper surface, an electrode body 2 accommodated in the battery can 1, and a non-aqueous electrolyte. And a horizontally long lid 3 that closes and seals the upper surface of the opening of the battery can 1, and an insulator 5 that is disposed inside the lid 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 lid 3.

  The electrode body 2 is produced, for example, by spirally winding a strip-shaped separator between a strip-shaped positive electrode and a strip-shaped negative electrode, and is flat in the wound state. In the positive electrode, a positive electrode active material layer containing a positive electrode active material such as lithium cobaltate is formed on both sides of a belt-like positive electrode current collector, and a thin plate-like positive electrode current collector lead 8 is derived from the positive electrode current collector. The

In the negative electrode, negative electrode active material layers containing a negative electrode active material such as graphite are formed on both front and back surfaces of a strip-shaped negative electrode current collector, and a thin plate-like negative electrode current collector lead 9 is led out from the negative electrode current collector. The separator is made of a microporous thin film such as polyethylene resin. The non-aqueous electrolyte was prepared by dissolving LiPF ₆ in a solvent obtained by mixing ethylene carbonate and methyl ethyl carbonate.

  The battery can 1 is a deep drawn product of aluminum or aluminum alloy plate. The lid 3 is a press-molded product made of aluminum or an aluminum alloy plate, and the outer peripheral edge of the lid 3 is seam welded to the opening peripheral edge of the battery can 1 with a laser beam such as a YAG laser. In the center of the lid 3, a negative electrode terminal (output terminal) 12 is attached in a penetrating manner via an upper insulating packing 10 and a lower insulating material 11. A lead body 13 made of a horizontally long rectangular nickel plate or the like is fixed to the lower end of the negative electrode terminal 12 on the inner surface of the lid 3. The insulating packing 10 and the insulating material 11 are made of an insulating resin such as polypropylene.

  Near the right end of the lid 3 in the lateral direction, a liquid injection hole 14 for injecting an electrolyte that is circular in plan view is formed in a vertically penetrating manner, and a nonaqueous electrolyte is injected into the battery case 6 from the liquid injection hole 14. After that, the sealing plug 15 is engaged with the liquid injection hole 14 and welded to the lid 3. The lead body 13 extends from the negative electrode terminal 12 toward the opposite side of the liquid injection hole 14.

  As shown in FIGS. 1 and 4, the negative electrode terminal 12 includes a flat rectangular head portion 17 and a columnar shaft portion 18 extending downward from the center of the lower surface of the head portion 17. The insulating packing 10 includes a flat rectangular head 20 that receives the head 17 of the negative terminal 12, and a cylindrical tube that extends downward from the center of the lower surface of the head 20 and passes through the shaft portion 18 of the negative terminal 12. Part 21. On the upper surface of the head 20 of the insulating packing 10, a recess 22 is provided in which the head 17 of the negative electrode terminal 12 is engaged. On the upper surface side in the center of the lid 3, a recess 24 is provided in which the head 20 of the insulating packing 10 is engaged. A through hole 25 that is circular in plan view is provided in the center of the recess 24. The shaft portion 18 of the negative electrode terminal 12 is inserted into the through hole 25 with the cylindrical portion 21 of the insulating packing 10 interposed between the negative electrode terminal 12 and the lid 3.

  The lead body 13 is integrally formed with the insulating material 11, and the upper surface of the lead body 13 and the front, rear, left and right side surfaces are covered with the insulating material 11. As a result, the lead body 13 is insulated from the lid 3. The lower surface of the lead body 13 is exposed from the insulating material 11 and the negative electrode current collecting lead 9 is welded. The lead body 13 is formed with an insertion hole 27 that is circular in plan view, and the insertion hole 27 has a lower end portion of the shaft portion 18 of the negative electrode terminal 12 protruding downward from the cylindrical portion 21 of the insulating packing 10. Is inserted. Note that the lead body 13 is formed in a corner-cut shape by cutting off four corners.

  The insulating material 11 is provided with a through hole 29 that is circular in a plan view with which the lower end portion of the cylindrical portion 21 of the insulating packing 10 is engaged. On the upper surface of the insulating material 11, there is formed an engagement recess (engagement portion) 30 that is circular in plan view with which the protrusion 26 provided on the lower surface of the lid 3 is engaged. Then, the protrusion 26 of the lid 3 is engaged with the engaging recess 30 of the insulating material 11, so that the integrally molded body of the insulating material 11 and the lead body 13 with respect to the lid 3 is prevented from rotating. Identification protrusions (identification portions) 31 and 31 for identifying the upper and lower sides of the insulating material 11 are provided on the left and right sides of the lower surface of the insulating material 11, respectively. On the lower surface side of the head 20 of the insulating packing 10, a recess 32 for saving resin is formed.

  As shown in FIG. 2, the positive electrode current collector lead 8 is welded to the space between the insulating material 11 and the liquid injection hole 14 on the back surface of the lid 3. Thus, the positive electrode current collecting lead 8 is electrically connected to the lid 3 and the battery can 1. A cleaving vent 33 is formed near the left end of the lid 3 in the left-right direction, and the cleaving vent 33 is cleaved to release the battery internal pressure when the battery internal pressure rises abnormally.

  A mold for integrally molding (insert molding) the insulating material 11 on the lead body 13 will be described with reference to FIGS. In the lower mold 36 of the mold 35, as shown in FIGS. 5 and 6, a circular hole with which the insertion hole 27 of the lead body 13 is engaged on the side closer to one end in the left-right direction of the lower surface 38 of the horizontally long inner space. A columnar engagement pin 39 protrudes upward. The upper end portion of the engagement pin 39 is formed in a tapered shape. Also, a pair of front and rear clamping pins 41 and 41 for sandwiching the lead body 13 from both front and rear sides are provided near the other end in the left and right direction on both sides 40 and 40 in the front and rear (up and down in FIG. 5) of the internal space of the lower die 36. It protrudes. Each pin 41 extends in the vertical direction along the inner surface of the internal space of the lower die 36 and is formed in a semicircular shape in cross section. As shown in FIG. 7, the upper part of each pin 41 is cut out in an inclined shape. On both the left and right sides of the lower surface 38 of the inner space of the lower mold 36, recesses 42 and 42 for forming the identification protrusions 31 and 31 of the insulating material 11 are respectively formed.

  An annular protrusion 47 is formed on the inner surface 46 of the upper mold 45 of the mold 35 to engage with the upper end of the engagement pin 39 of the lower mold 36 to form the through hole 29 of the insulating material 11. . A cylindrical projection 49 for forming the engagement recess 30 of the insulating material 11 is formed on the inner surface 46 of the upper mold 45. On the inner surface 46 of the upper mold 45, a protrusion 51 having an opening 50 a of the gate 50 disposed at the lower end bulges toward the inner space side of the mold 35. Molten resin is injected from the opening 50 a of the gate 50 into the internal space of the mold 35.

  When the insulating material 11 is formed integrally with the lead body 13, the insertion hole 27 of the lead body 13 is engaged with the engagement pin 39 of the lower die 36, and the lead body 13 is held between the front and rear clamping pins 41 and 41. Fit between. Thus, the lead body 13 is positioned in the internal space of the upper mold 45 by the engagement pin 39 and the front and rear holding pins 41 and 41. After the lead body 13 is mounted in the inner space of the mold 35, the upper mold 45 is mounted on the lower mold 36 and molten resin is injected from the gate 50 into the inner space of the mold 35. As a result, as shown in FIG. Note that the annular protrusion 47 restricts the floating of the lead body 13 in the mold 35.

  When assembling the battery, the cylindrical portion 21 of the insulating packing 10 is inserted into the through hole 25 of the lid 3, and the shaft portion 18 of the negative electrode terminal 12 is inserted into the cylindrical portion 21 of the insulating packing 10. Further, the lower end portion of the cylindrical portion 21 of the insulating packing 10 is inserted into the through hole 29 of the insulating material 11, and the lower end portion of the shaft portion 18 of the negative electrode terminal 12 is inserted into the insertion hole 27 of the lead body 13. In this state, the negative electrode terminal 12 is caulked and the lower end portion of the shaft portion 18 of the negative electrode terminal 12 is spread outward, and the negative electrode terminal 12, the insulating packing 10, the insulating material 11, and the lead body 13 are integrated with the lid 3. Each of the molded bodies is fixed.

  Next, after the electrode body 2 and the insulator 5 are accommodated in the battery can 1, the negative electrode current collector lead 9 is spot welded to the lower surface of the lead body 13 not covered with the insulating material 11, and the positive electrode is connected to the lower surface of the lid 3. The current collecting lead 8 is spot welded. Thereafter, the lid 3 is seam welded to the periphery of the opening of the battery can 1, and the inside of the battery can 1 is vacuum-reduced to inject a non-aqueous electrolyte from the liquid injection hole 14. After the injection of the non-aqueous electrolyte is completed, the sealing plug 15 is engaged with the liquid injection hole 14 and laser welded to the peripheral portion of the liquid injection hole 14 of the lid 3. Thus, the battery shown in FIG. 2 is formed.

  In the insulating material 11 after molding, non-insulating portions 52 and 52 are respectively formed in front and rear corresponding to the contact between the both pinching pins 41 and 41 and the lead body 13, and as shown in FIG. The side surfaces of the lead body 13 are exposed at the portions 52 and 52, but there is a distance between the side surface of the lead body 13 and the inner surface of the battery can 1, so the side surfaces of the lead body 13 exposed at the non-insulating portions 52 and 52 are However, it does not contact the inner surface of the battery can 1.

  Thus, since the lead body 13 and the insulating material 11 are integrated, the number of parts at the time of manufacture of a battery can be reduced rather than the case where the lead body 13 and the insulating material 11 are made into a different body. For example, even if the lead body 13 rotates about the negative electrode terminal 12, the lead body 13 contacts the inner surface of the battery can 1 and is short-circuited by the insulating material 11 that rotates integrally with the lead body 13. Is reliably prevented.

  An engagement pin 39 that engages with the insertion hole 27 of the lead body 13 and a pair of sandwiching pins that sandwich the lead body 13 from the front and rear in an internal space of a mold 35 for integrally molding the insulating material 11 on the lead body 13. Since 41 and 41 are provided, the sliding movement of the lead body 13 in the lateral direction is restricted by the engagement of the engagement pin 39 and the insertion hole 27 of the lead body 13 in the mold 35. In addition, the rotation of the lead body 13 around the engaging pin 39 is restricted by the pinching pins 41 and 41. That is, the lead body 13 is reliably positioned in the mold 35 by the engagement pin 39 and the front and rear clamping pins 41 and 41.

  In addition, since only two clamping pins 41 and 41 are in contact with the front, rear, left, and right inner surfaces of the lead body 13, the non-insulating portions 52 that are not covered with the insulating material 11 along with the positioning on the front, rear, left, and right inner surfaces of the lead body 13. -52 can be suppressed to only two places. That is, the exposed portions of the lead body 13 can be minimized at the front, rear, left and right of the lead body 13, and the front, rear, left and right of the lead body 13 can be more reliably prevented from coming into contact with the inner surface of the battery can 1 and the like.

  In the lower mold 36 of the mold 35, each clamping pin 41 may be arranged away from the inner surface of the inner space of the lower mold 36. The pin 41 may be formed in a triangle, a quadrangle, or the like in the cross section. The identification protrusions 31 of the insulating material 11 may be omitted. The output terminal 12 may be a positive electrode, and the battery can 1 and the lid 3 may be a negative electrode.

It is a vertical front view which shows the principal part of the sealed battery which concerns on this invention. It is a vertical front view of the sealed battery which concerns on this invention. It is the sectional view on the AA line of FIG. It is a disassembled perspective view of the cover part of a sealed battery. It is a cross-sectional top view which shows the state which mounted | wore the lead | metal | die body with the metal mold | die for insulation materials. FIG. 6 is a sectional view taken along line B-B in FIG. 5. It is CC sectional view taken on the line of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Battery can 2 Electrode body 3 Cover | cover 9 Negative electrode current collection lead 10 Insulation packing 11 Insulation material 12 Negative electrode terminal 13 Lead body 25 Through hole 26 Engagement protrusion 27 Insertion hole 30 Engagement recessed part 31 Identification protrusion 35 Mold 39 Engagement pin 41 pinching pin

Claims (4)

A through hole for inserting the output terminal is formed in the lid that closes the upper open surface of the left and right horizontally long battery cans, and the output terminal is inserted with an insulating packing interposed between the output terminal and the lid. At the lower end of the output terminal that is inserted through the through-hole and protrudes to the lower side of the lid, a horizontally long lead body is attached together with a resin insulating material,
In the method of manufacturing a sealed battery, the current collector lead connecting from the electrode body accommodated in the battery can is connected to the lead body,
The lead body is formed with an insertion hole through which the lower end of the output terminal is inserted, and the insulating material is integrally formed with the lead body,
An engagement pin that engages with the insertion hole of the lead body and a pair of front and rear clamping pins that sandwich the lead body from the front and rear are disposed in the inner space of the mold for integrally molding the insulating material on the lead body. And
After engaging the insertion hole of the lead body with the engagement pin, fitting the lead body between the pair of clamping pins, and mounting the lead body in the internal space of the mold, A method of manufacturing a sealed battery, wherein molten resin is injected into the inner space of the mold, and the insulating material is coated on front, rear, left, right, and upper surfaces of the lead body. An engaging protrusion protrudes from the lower surface of the lid,
The method for manufacturing a sealed battery according to claim 1, wherein when the insulating material is integrally formed on the lead body, an engaging portion that engages with the engaging protrusion is formed on an upper surface of the insulating material.   The method for manufacturing a sealed battery according to claim 1 or 2, wherein when the insulating material is integrally formed on the lead body, an identification portion for identifying the upper and lower sides of the insulating material is formed on the lower surface of the insulating material. A battery can having left and right horizontally open upper surfaces;
A lid for closing the upper surface of the opening of the battery can;
An output terminal fixed in a state of being inserted into a through hole provided in the lid;
Insulating packing interposed between the lid and the output terminal;
Left and right laterally long lead bodies attached to the lower end portion of the output terminal protruding to the lower side of the lid;
With
A current collecting lead extending from the electrode body accommodated in the battery can is connected to the lead body,
The lead body has an insertion hole through which the lower end of the output terminal is inserted,
A sealed battery, wherein the lead body is integrally formed with an insulating material covering an upper surface and left and right side surfaces of the lead body.

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