JP2013105678A - Sealed battery and method for manufacturing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sealed battery and a method for manufacturing the same for facilitating manufacturing processes.SOLUTION: A tentative encapsulation member 60 of a battery 10 is constituted of: a cylindrical member 61 which is an elastic body including a body part 62 at the shaft center part of which a communication hole 65 is opened, the outer diameter of which is formed approximately the same as an inner diameter of a liquid injection hole 32b, and flange parts 63, 64 which are arranged on both ends in the shaft center direction of the body part 62, the outer diameter of which is formed as larger than the inner diameter of the liquid injection hole 32b, and project from the body part 62 to the outside of the radial direction; and a rod-like member 66 which is formed with larger diameter than the inner diameter of the communication hole 65 and one end of which is inserted into the communication hole 65, and a method for manufacturing the battery 10 includes: a tentative encapsulation process of tentatively encapsulating the liquid injection hole 32b by the tentative encapsulation member 60 at a state that the rod-like member 66 is inserted into the communication hole 65; a communication process of communicating the inside and the outside of a battery housing with each other by extracting the rod-like member 66 from the communication hole 65; and an encapsulation process of encapsulating the liquid injection hole 32b by an encapsulation member 71.

Description

  The present invention relates to a sealed battery and a method for manufacturing the same, and particularly to a technique for sealing a liquid injection hole of a battery container.

  Conventionally, in a sealed battery such as a lithium ion secondary battery or a nickel hydride secondary battery, a charging / discharging element (a positive electrode, a negative electrode, a separator, etc.) is accommodated in a battery container, and an injection solution is injected after an electrolyte is injected. A structure for sealing is known.

  In the process of manufacturing the sealed battery as described above, first, an electrolytic solution is injected into the battery container through the injection hole, and then the temporary sealing film (first sealing film) is placed around the injection hole. The liquid injection hole is temporarily sealed by welding. In this state, after initial charging and activating the battery, a hole is formed in the temporary sealing film to form a gas vent passage that communicates the inside and outside of the battery container. Excess gas is discharged to the outside. Furthermore, in order to seal the battery so that the internal electrolyte does not leak, the injection hole of the battery container is sealed with a sealing film (second sealing film) (see, for example, Patent Document 1).

JP 2009-181906 A

  However, in the technique described in Patent Document 1, the step of opening a hole in the temporary sealing film and the step of sealing the hole opened in the temporary sealing film with the sealing film are separate steps, and each is continuous. Therefore, the manufacturing process of the sealed battery is complicated. In other words, each process requires a separate process (for example, a punch for making a hole in the temporary sealing film, a sealing film for sealing the temporary sealing film, etc.), and thus the manufacturing process is necessary. It was a complicated factor.

  In view of the above situation, the present invention provides a sealed battery and a method for manufacturing the same, which can simplify the manufacturing process.

  The problem to be solved by the present invention is as described above. Next, means for solving the problem will be described.

  That is, in claim 1, a battery container having a liquid injection hole for injecting an electrolytic solution, a temporary sealing member for temporarily sealing the liquid injection hole, and a seal for sealing the liquid injection hole. A temporary sealing member, wherein the temporary sealing member has a communication hole formed in an axial center portion thereof, and an outer diameter thereof is larger than an inner diameter of the liquid injection hole. A cylindrical member that is an elastic body, and a rod-shaped member that is formed to have a diameter larger than the inner diameter of the communication hole and that can be inserted into the communication hole, and the rod-shaped member is inserted into the communication hole. In addition, the cylindrical member is inserted into the liquid injection hole, the temporary sealing member is elastically deformed to temporarily seal the liquid injection hole, and the rod-shaped member is pulled from the communication hole. By disconnecting, the inside and outside of the battery container are in communication with each other, and the liquid injection hole is sealed with the sealing member. A sealing step of, is provided with a.

  According to a second aspect of the present invention, the cylindrical member includes a main body portion having a communication hole formed in an axial center portion thereof and having an outer diameter larger than an inner diameter of the liquid injection hole, and an axial direction of the main body portion. And a flange portion that has an outer diameter larger than the inner diameter of the liquid injection hole and protrudes radially outward from the main body portion.

  In Claim 3, the said rod-shaped member is a product made from resin.

  A fourth aspect of the present invention is a sealed battery manufactured by the method for manufacturing a sealed battery according to any one of the first to third aspects.

  According to the present invention, the manufacturing process can be simplified in manufacturing a sealed battery.

1 is a front sectional view showing a schematic configuration of a sealed battery according to an embodiment. Sectional drawing which showed the vicinity of the injection hole of a sealed battery similarly. The flowchart which concerns on the manufacturing method of a sealed battery similarly. Sectional drawing which showed the initial state in the vicinity of a liquid injection hole similarly. Sectional drawing which showed the state before temporary sealing in the vicinity of a liquid injection hole similarly. Sectional drawing which showed the state currently temporarily sealed in the vicinity of the liquid injection hole. Sectional drawing which showed the state which made the inside and the exterior connect similarly in the vicinity of a liquid injection hole.

Next, embodiments of the invention will be described.
It should be noted that the technical scope of the present invention is not limited to the following examples, but broadly covers the entire scope of the technical idea that the present invention truly intends, as will be apparent from the matters described in the present specification and drawings. It extends.

[Battery 10]
With reference to FIG. 1, a schematic configuration of a battery 10 which is an embodiment of the battery according to the present invention will be described. The battery 10 of this embodiment is a sealed lithium ion secondary battery. The target to which the present invention is applied is not limited to the lithium ion secondary battery, but can be applied to other sealed batteries such as a nickel hydrogen secondary battery.

  The battery 10 includes a power generation element 20, an exterior 30 that is a battery container that houses the power generation element 20, external terminals 40 and 40 that protrude outward from the exterior 30, and the external terminals 40 and the exterior 30. And insulating members 50 and 51 interposed therebetween.

  The power generation element 20 is obtained by impregnating an electrolytic solution into an electrode body formed by laminating or winding a positive electrode, a negative electrode, and a separator. When the battery 10 is charged / discharged, a chemical reaction occurs in the power generation element 20 (strictly speaking, ion movement occurs between the positive electrode and the negative electrode via the electrolytic solution), thereby generating a current flow.

The exterior 30 that is a battery container is a prismatic can having a storage portion 31 and a lid portion 32. The storage unit 31 is a bottomed rectangular tube-shaped member that is open on one side, and stores the power generation element 20 therein. The lid portion 32 is a flat member having a shape corresponding to the opening surface of the storage portion 31 and is joined to the storage portion 31 in a state where the opening surface of the storage portion 31 is closed. As will be described later, in the lid portion 32, a liquid injection hole 32b for injecting an electrolytic solution is opened between locations where the external terminals 40 and 40 are inserted.
In addition, although the battery 10 of the present embodiment is configured as a prismatic battery in which the exterior 30 is formed in a bottomed rectangular tube shape, the present invention is not limited to this, and for example, the exterior 30 has a bottomed cylindrical shape. It is also possible to apply to the cylindrical battery formed in the above.

The external terminals 40 and 40 are arranged in a state where a part of the external terminals 40 protrudes outward from the battery 10 from the outer surface of the lid portion 32. The external terminals 40 and 40 are electrically connected to the positive electrode or the negative electrode of the power generation element 20 via current collecting terminals 45 and 45. The external terminals 40 and 40 and the current collecting terminals 45 and 45 function as an energization path for taking out the electric power stored in the power generation element 20 to the outside or taking in electric power from the outside into the power generation element 20.
The current collecting terminals 45 and 45 are connected to the positive electrode plate and the negative electrode plate of the power generation element 20. As a material for the current collecting terminals 45 and 45, for example, aluminum can be used on the positive electrode side and copper on the negative electrode side.

  Each external terminal 40 is fixed in an insulated state with respect to the lid portion 32 with insulating members 50 and 51 interposed therebetween by fitting a fixing member 35 on the outer peripheral surface portion thereof. The material of the insulating members 50 and 51 is preferably a material having excellent high-temperature creep characteristics, that is, a material having long-term creep resistance against the cooling cycle of the battery 10, such as PFA (perfluoroalkoxyethylene).

  The external terminals 40 and 40 are threaded by screw rolling at portions protruding outward of the battery 10 to form bolt portions. When the battery 10 is actually used, a bus bar, a connection terminal of an external device, and the like are fastened and fixed to the external terminals 40 and 40 using the bolt portion. When fastening and fixing, since external torque is applied to the external terminals 40 and 40 and external force is applied in the axial direction by screw fastening, a high-strength material such as iron is adopted as the material of the external terminals 40 and 40. It is preferable.

[Liquid injection hole 32b]
Next, with reference to FIG. 2, a configuration in the vicinity of the liquid injection hole 32b of the battery 10 according to the present embodiment will be described. The liquid injection hole 32b is formed so as to be opened between the external terminals 40 and 40 in the lid portion 32 as described above. The liquid injection hole 32 b is a through hole having a predetermined inner diameter, and penetrates the lid portion 32 in the thickness direction of the lid portion 32. The liquid injection hole 32b is used to inject an electrolytic solution into the exterior 30 in which the power generation element 20 is accommodated in advance. On the upper side of the liquid injection hole 32b, a first large diameter part 32a whose inner diameter is formed larger than the liquid injection hole 32b, and a second large diameter whose inner diameter is formed larger than the first large diameter part 32a. The portion 32c is formed in stages. The second large diameter portion 32c is disposed above the first large diameter portion 32a.

The liquid injection hole 32b includes a cylindrical member 61 that is a constituent member of the temporary sealing member 60 (see FIGS. 4 to 6) that temporarily seals the liquid injection hole 32b, and a seal that seals the liquid injection hole 32b. A stop member 71 is attached.
As shown in FIGS. 4 to 6, the temporary sealing member 60 includes a cylindrical member 61 that is an elastic body (for example, a rubber body) and a rod-shaped member 66.

The cylindrical member 61 is an elastic body including a main body 62 and flanges 63 and 64, and is configured to be elastically deformable.
The main body 62 has a communication hole 65 formed in the axial center portion of the cylindrical member 61, and has an outer diameter slightly larger than the inner diameter of the liquid injection hole 32b. A tapered surface 65 a that increases in diameter toward the upper side is formed in the upper portion of the communication hole 65. The flange portions 63 and 64 are disposed at both end portions in the axial direction of the main body portion 62, and the outer diameter thereof is formed larger than the inner diameter of the liquid injection hole 32 b, so that the outer peripheral surface of the main body portion 62 is radially outward. And projecting. As shown in FIG. 2, the upper flange portion 63 has a slightly smaller diameter and a smaller vertical width than the first large diameter portion 32a. That is, the flange part 63 is formed in a size that can be completely accommodated in the first large diameter part 32a.

  The rod-shaped member 66 is formed to have a diameter larger than the inner diameter of the communication hole 65, and a lower end portion which is one end portion thereof can be inserted into the communication hole 65 as shown in FIGS. The insertion side end (lower end) 66a of the rod-shaped member 66 is formed to have a reduced diameter as it goes to the tip. In the present embodiment, the rod-like member 66 is formed as a resin member.

  The sealing member 71 is a metal plate-like member, and is formed so as to have substantially the same diameter as the inner diameter of the second large-diameter portion 32c and the vertical width thereof is substantially the same as that of the second large-diameter portion 32c. Is done. That is, the sealing member 71 is formed in a size that can be completely accommodated in the second large diameter portion 32c. In this embodiment, when sealing the injection hole 32b with the sealing member 71, it is welded to the cover part 32 in the peripheral part of the sealing member 71, as shown in FIG. However, the mode of sealing the liquid injection hole 32b is not limited to the configuration of the present embodiment, and may be configured to be sealed using another fastening jig or the like.

[Method for Manufacturing Battery 10]
Next, a method for manufacturing the battery 10 will be described with reference to FIGS. In addition, each process in the manufacturing method of the battery 10 described below accommodates the power generation element 20 in the storage portion 31, closes the opening of the storage portion 31 with the lid portion 32, and stores the storage portion 31 and the lid portion 32. It is a process performed after joining.

  Before performing the following steps, the insertion-side end portion 66a of the rod-shaped member 66 is inserted into the communication hole 65 in the tubular member 61 as indicated by an arrow A in FIG. At this time, as shown in FIG. 5, the tapered surface 65a and the insertion-side end portion 66a of the cylindrical member 61 are formed in a tapered shape, so that the contact area between them increases. For this reason, between the cylindrical member 61 and the rod-shaped member 66 (communication hole 65) can be obstruct | occluded with high airtightness. In this manner, the temporary sealing member 60 is configured by inserting the rod-shaped member 66 into the communication hole 65 of the cylindrical member 61.

  In step S01 shown in FIG. 3, an electrolytic solution is injected into the exterior 30 through the injection hole 32b. Specifically, the electrolyte solution is filled into the exterior 30 through the liquid injection hole 32b formed in the lid portion 32, and the electrolyte solution is infiltrated into the power generation element 20 that is an electrode body.

  After a predetermined amount of electrolytic solution has been injected into the exterior 30, in step S02 shown in FIG. 3, the temporary member 66 is inserted into the communication hole 65 as shown by the arrow B in FIG. The sealing member 60 is moved downward to be close to the lid portion 32 and inserted into the liquid injection hole 32b. Then, as shown in FIG. 6, the outer periphery of the main body 62 is elastically deformed (reduced in diameter) to close the liquid injection hole 32 b, and the liquid injection hole 32 b is formed by the temporary sealing member 60 by the elastic force of the main body 62. Temporary sealing (temporary sealing step). At this time, the flange portion 63 is in contact with the first large diameter portion 32 a, thereby preventing the temporary sealing member 60 from falling into the exterior 30.

  In the present embodiment, the rod-shaped member 66 is inserted into the communication hole 65 and then the temporary sealing member 60 is inserted into the liquid injection hole 32b. However, the cylindrical member 61 is first inserted into the liquid injection hole 32b. It is also possible to adopt a configuration in which the rod-shaped member 66 is inserted into the communication hole 65 after the insertion. In this case, even when the rod-shaped member 66 is inserted into the communication hole 65, the temporary sealing member 60 can be prevented from falling off by the flange portion 63 coming into contact with the first large diameter portion 32a.

  Thereafter, in step S03 shown in FIG. 3, the activation process of the battery 10 is performed by repeating the initial charge and discharge cycles. At this time, surplus gas is generated inside the exterior 30 which is a battery container by the activation process. However, since the liquid injection hole 32 b is temporarily sealed with the temporary sealing member 60 as described above, excess gas does not flow out of the exterior 30. At this time, as described above, the space between the tubular member 61 and the rod-shaped member 66 (communication hole 65) is closed with high airtightness, so that excess gas may flow out of the exterior 30 through the communication hole 65. Absent. Further, the flange portion 64 abuts against the lower surface of the lid portion 32, thereby preventing the temporary sealing member 60 from coming off due to the internal pressure of the exterior 30.

  Thereafter, in step S04 shown in FIG. 3, the rod-shaped member 66 is pulled out from the communication hole 65 as indicated by an arrow C in FIG. 6. Thereby, the exterior 30 and the lid part 32 which are battery containers are communicated with each other via the communication hole 65 (communication process). Thereby, the surplus gas in the exterior 30 generated in the activation process is discharged to the outside as indicated by a broken line arrow G in FIG.

  Thereafter, in step S05 shown in FIG. 3, as shown by an arrow D in FIG. 7, the sealing member 71 is moved downward and accommodated in the second large diameter portion 32c. And as shown in FIG. 2, it welds to the cover part 32 in the peripheral part of the sealing member 71, and seals the liquid injection hole 32b (sealing process). In this way, the sealed battery 10 is completed with the exterior 30 sealed.

  As described above, in the method for manufacturing the battery 10 according to the present embodiment, the temporary sealing member 60 is formed with the communication hole 65 at the axial center and the outer diameter of the temporary sealing member 60 being substantially the same as the inner diameter of the liquid injection hole 32b. A main body portion 62, and flange portions 63 and 64 that are formed at both ends in the axial direction of the main body portion 62 to have an outer diameter larger than the inner diameter of the liquid injection hole 32b and project outward in the radial direction. A cylindrical member 61 that is an elastic body, and a rod-shaped member 66 that has a diameter larger than the inner diameter of the communication hole 65 and that can be inserted into the communication hole 65 at one end thereof.

  And the manufacturing method of the battery 10 inserts the rod-shaped member 66 in the communicating hole 65, temporarily seals the liquid injection hole 32b with the temporary sealing member 60, and the rod-shaped member 66 from the communicating hole 65. By pulling out, a communication process for allowing the inside and the outside of the battery container to communicate with each other and a sealing process for sealing the liquid injection hole 32b with the sealing member 71 are provided.

  According to the manufacturing method of the battery 10 according to the present embodiment, the cylindrical member 61 that is an elastic body in the temporary sealing member 60 is elastically deformed to close the liquid injection hole 32b and temporarily seal the liquid injection hole 32b. Therefore, the operation for temporarily sealing the liquid injection hole 32b can be simplified as compared with the prior art. And the inside of the exterior | packing 30 and the cover part 32 which are battery containers can be connected by only pulling out the rod-shaped member 66 from the communicating hole 65. FIG. In other words, it is not necessary to remove the cylindrical member 61 that closes the liquid injection hole 32b with a strong frictional force due to the elastic deformation of the main body 62. That is, the process in the manufacturing method of the battery 10 can be simplified.

  In addition, since the rod-shaped member 66 in the present embodiment is formed as a resin member, it is possible to prevent the occurrence of metallic foreign matters in the temporary sealing process.

10 Battery 30 Exterior (battery container)
32 Lid portion 32b Injection hole 60 Temporary sealing member 61 Cylindrical member 62 Body portion 63 Flange portion 64 Flange portion 65 Communication hole 66 Rod-shaped member 71 Sealing member

Claims (4)

A sealed type comprising: a battery container having a liquid injection hole for injecting an electrolytic solution; a temporary sealing member for temporarily sealing the liquid injection hole; and a sealing member for sealing the liquid injection hole. A battery manufacturing method comprising:
The temporary sealing member includes a cylindrical member that is an elastic body having a communication hole opened in an axial center portion thereof and an outer diameter larger than the inner diameter of the liquid injection hole, and a larger diameter than the inner diameter of the communication hole. A rod-shaped member that is formed in a diameter and can be inserted into one end of the communication hole,
A temporary sealing step of inserting the rod-shaped member into the communication hole, inserting the cylindrical member into the liquid injection hole, and elastically deforming the temporary sealing member to temporarily seal the liquid injection hole; ,
A communication step of connecting the inside and the outside of the battery container by pulling out the rod-shaped member from the communication hole;
And a sealing step of sealing the liquid injection hole with the sealing member.   The cylindrical member is disposed at a main body portion in which a communication hole is opened at an axial center portion thereof and an outer diameter thereof is larger than an inner diameter of the liquid injection hole, and at both end portions in the axial direction of the main body portion. 2. The sealed battery according to claim 1, further comprising a flange portion having an outer diameter larger than an inner diameter of the liquid injection hole and projecting radially outward from the main body portion. Production method.   The method for manufacturing a sealed battery according to claim 1, wherein the rod-shaped member is made of a resin.   A sealed battery manufactured by the method for manufacturing a sealed battery according to any one of claims 1 to 3.

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