JP5470603B2 - Sealed battery - Google Patents

Description

  The present invention relates to a sealed battery.

In recent years, sealed batteries have been used for various applications, and particularly large sealed batteries have been used for applications such as electric vehicle power supplies and power storage.
Various improvements are required for such a large sealed battery. In particular, in the structure of the electrode terminal and the connection between the electrode terminal and the external wiring, reduction in internal resistance, reduction in manufacturing cost, weight reduction, reliability of electrical connection between the electrode terminal and external wiring, and the like are required.
Thus, a secondary battery has been proposed that can reduce internal resistance by firmly connecting a rivet terminal and a current collector connector (see, for example, Patent Document 1).

JP 2004-14173 A

However, in the conventional battery, since the current collector connection body connected to the power generation element inside the battery and the electrode terminal connected to the external wiring are separate members, contact resistance is generated at the contact portion of the different members, and the internal resistance is reduced. Increasing.
In addition, in the conventional battery, since a female screw structure or the like is directly formed on the electrode terminal to bring the electrode terminal into contact with the external wiring, it is necessary to use a metal lump as a raw material for the electrode terminal, which increases the manufacturing cost. And led to an increase in battery weight.
In addition, in the conventional battery, when the electrode terminal and the external wiring are brought into contact with each other and the contact state is maintained by the tightening force by the bolt-nut structure, the high temperature stability or durability of resin or rubber is included in the tightening structure. In this case, when the battery heats up and the temperature rises, or when the battery is used for a long time, the bolts and nuts that contact the electrode terminal and external wiring loosen and the electrode terminal There is a risk that the contact resistance between the wiring and the external wiring increases.
The present invention has been made in view of such circumstances, and provides a sealed battery that can be manufactured at a reduced manufacturing cost and has a small internal resistance.

  The present invention includes a positive electrode connecting terminal and a negative electrode connecting terminal which are respectively bonded to the lid member via an insulating member, a separator, and a positive electrode and a negative electrode which are arranged via the separator, in a case where the lid member is bonded. The positive electrode and the negative electrode are connected to the positive electrode connection terminal and the negative electrode connection terminal, respectively, and the positive electrode connection terminal and the negative electrode connection terminal pass through the lid member, respectively, and the lid member Each of the cases has a plate-like external connection part that partitions the outside and the inside of the case, and the external connection part is joined to a screw member that penetrates a part of the case. Provided is a sealed battery having a screw part that can be fastened to either side and a caulking part that is joined to the external connection part by a caulking structure.

According to the present invention, since the connection from the power generation element inside the battery to the connection of the external wiring outside the battery can be performed with one member, the internal resistance of the battery can be reduced.
Further, since the screw members are joined to the external connection portions of the positive electrode connection terminal and the negative electrode connection terminal by caulking structures, respectively, metal plates processed into the positive electrode connection terminal and the negative electrode connection terminal can be used, which can reduce the manufacturing cost. it can.
In addition, according to the present invention, since all of the bolts or nuts corresponding to the positive electrode connection terminal or the negative electrode connection terminal, the external wiring, the screw portion of the screw member, and the screw portion can be used, the temperature rises, etc. Thus, loosening of the bolt and nut can be prevented.
Further, according to the present invention, since the positive electrode connection terminal and the negative electrode connection terminal each have an external connection part that partitions the battery outside and the battery inside, the lid member, the external connection part of the positive electrode connection terminal, and the external connection part of the negative electrode connection terminal, Can be eliminated, and the weight and cost can be reduced.

(A) is a schematic perspective view which shows the structure of the sealed battery of one Embodiment of this invention, (b) is the schematic sectional drawing, (c) is the range A enclosed with the dotted line of (b), or FIG. It is explanatory drawing which shows the structure of the electric power generation element contained in the sealed battery of one Embodiment of this invention. (A) is a schematic perspective view which shows the structure before joining with the external connection part of the screw member contained in the sealed battery of one Embodiment of this invention, (b) is the schematic side view, (c ) Is a schematic cross-sectional view taken along the dotted line AA shown in (b), (d) is a schematic cross-sectional view taken along the dotted line BB shown in (b), and (e) is another embodiment of the present invention. It is a schematic sectional drawing of the screw member contained in the sealed battery of a form. (A) is a schematic perspective view which shows the structure before joining with the external connection part of the screw member contained in the sealed battery of one Embodiment of this invention, (b) is the schematic side view, (c ) And (d) are schematic cross-sectional views taken along the dotted line AA shown in (b), (e) is a schematic cross-sectional view taken along the dotted line BB shown in (b), and (f) is the present invention. It is a schematic sectional drawing of the screw member contained in the sealed battery of other embodiment. (A) is a schematic plan view which shows the external connection metal plate contained in the sealed battery of one Embodiment of this invention, (b) contacts the external connection metal plate, a positive electrode connection terminal, or a negative electrode connection terminal. It is a schematic sectional drawing which shows the state fixed so. (A) And (b) is explanatory drawing which shows the method of joining the screw member and the positive electrode connection terminal or negative electrode connection terminal which are contained in the sealed battery of one Embodiment of this invention by a crimping structure.

  The sealed battery of the present invention is disposed in a case where a lid member is joined, with a positive electrode connection terminal and a negative electrode connection terminal respectively joined to the lid member via an insulating member, a separator, and the separator. A positive electrode and a negative electrode; and an electrolyte solution, wherein the positive electrode and the negative electrode are connected to the positive electrode connection terminal and the negative electrode connection terminal, respectively, the positive electrode connection terminal and the negative electrode connection terminal penetrate the lid member, and Each of the cases has a plate-like external connection part that partitions the outside and the inside of the case joined to the lid member, and the external connection part is joined to a screw member that penetrates a part thereof, and the screw member is a nut. And a screw part that can be fastened to either one of the bolts and a caulking part that is joined to the external connection part by a caulking structure.

A sealed battery is a battery having a sealed structure.
The case is a case that accommodates the positive electrode, the negative electrode, the separator, and the electrolyte, and is joined to the lid member.
The lid member is a member that can be joined to the case and seal the battery.

The positive electrode connection terminal is a connection terminal that can be connected to the positive electrode inside the battery and can be connected to external wiring outside the battery.
The negative electrode connection terminal is a connection terminal that can be connected to the negative electrode inside the battery and can be connected to external wiring outside the battery.
The electrolytic solution is an electrolytic solution that fills the inside of the battery and can cause a battery reaction with the positive electrode and the negative electrode.
The screw member is a member for connecting and fixing any one of the positive electrode connection terminal and the negative electrode connection terminal and the external wiring.
In the present invention, a “bolt” is a part having a male screw structure or a part having a male screw structure. Further, the “nut” is said to have a part having a female screw structure or a female screw structure. “Screw” refers to “bolt”, “nut”, or both.

In the sealed battery according to the aspect of the invention, it is preferable that the screw member further includes a flange portion having a first surface facing the outside and a second surface facing the inside.
According to such a structure, when the said screw member and the said external connection part are joined by a crimping structure, the plastic deformation of a screw part can be prevented.

In the sealed battery of the present invention, it is preferable that the screw portion has a male screw structure and is provided on the first surface, and the crimping portion is provided on the second surface.
According to such a configuration, the caulking portion can be passed through the external connection portion, and the caulking portion and the external connection portion can be joined by the caulking structure, and the screw portion is fastened with the external nut, The external connection portion and the external wiring can be fixed so as to contact each other.

In the sealed battery of the present invention, the screw portion is a portion having a female screw structure provided in the screw member, the flange portion is provided at one end of the screw member, and the crimping portion is It is preferable to be provided at the other end of the screw member.
According to such a configuration, the caulking portion can be passed through the external connection portion, and the caulking portion and the external connection portion can be joined by the caulking structure, and the screw portion is fastened with the external bolt, The external connection portion and the external wiring can be fixed so as to contact each other.

In the sealed battery according to the aspect of the invention, it is preferable that the screw member has a convex portion on the second surface, and the external connection portion has a shape plastically deformed so as to be in contact with an outer peripheral portion of the flange portion. .
According to such a configuration, the external connection portion can have a shape corresponding to the shape of the convex portion, and when the screw member and the corresponding nut or bolt are fastened together, the screw member can be prevented from rotating together. Can do.

In the sealed battery according to the aspect of the invention, it is preferable that the first surface is a surface on the same surface as the outer surface facing the outside of the external connection portion or a surface closer to the inside than the outer surface.
According to such a configuration, the external connection portion can be easily brought into contact with the external wiring, the number of parts can be reduced, and the manufacturing cost can be reduced.

The sealed battery of the present invention preferably further includes a resin member that covers a boundary portion between the external connection portion and the crimping portion.
With such a configuration, a slight gap between the external connection portion and the caulking portion can be closed, and the sealing performance can be improved.

The sealed battery of the present invention further includes an external connection metal plate which is an external wiring electrically connected to the external connection portion and has an opening, and the external connection metal plate passes the bolt through the opening and the screw. Preferably, the external connection metal plate has a matte nickel plating layer on the surface thereof, and is fixed to come into contact with the external connection portion by tightening a portion and a corresponding nut or bolt.
With such a configuration, the external connection portion and the external connection metal plate can be brought into contact with each other. In addition, when the external connection metal plate has a matte nickel plating layer on the surface, the external connection metal plate and the positive electrode are used when a metal that may be deteriorated in the connection surface is used for the positive electrode connection terminal or the negative electrode connection terminal. It is possible to suppress the occurrence of contact failure or increase in contact resistance at the interface with the connection terminal or the negative electrode connection terminal.

In the sealed battery of the present invention, the positive electrode has a positive electrode active material layer containing lithium, the negative electrode has a negative electrode active material layer containing graphite, and the electrolytic solution uses a lithium salt solute as an organic solvent. A dissolved solution is preferred.
With this configuration, the sealed battery of the present invention can be a lithium ion secondary battery.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings. The configurations shown in the drawings and the following description are merely examples, and the scope of the present invention is not limited to those shown in the drawings and the following description.

Diagram 1 of the sealed type battery is like schematic perspective view showing the configuration of a sealed battery according to one embodiment of the present invention. FIG. 2 is an explanatory view showing the configuration of the power generation element, and FIGS. 3 and 4 are schematic perspective views showing the configuration before joining to the external connection portion of the screw member included in the sealed battery of one embodiment of the present invention. It is a figure. FIG. 5 is a schematic plan view showing an external connection metal plate included in the sealed battery according to the embodiment of the present invention.

  The sealed battery 20 according to the present embodiment includes a positive electrode connection terminal 3 and a negative electrode connection terminal 4 respectively bonded to the lid member 2 via the insulating member 10 inside the case 1 to which the lid member 2 is bonded, a separator 24, A positive electrode 21 and a negative electrode 22 arranged via a separator 24, and an electrolyte solution are provided. The positive electrode 21 and the negative electrode 22 are connected to the positive electrode connection terminal 3 and the negative electrode connection terminal 4, respectively, and the positive electrode connection terminal 3 and the negative electrode connection terminal 4 have plate-like external connection portions 8 that respectively penetrate the lid member 2 and separate the outside and the inside of the case 1 joined to the lid member 2, and the external connection portion 8 is a part of this. The threaded member 6 is joined to the threaded member 6 that passes therethrough, and the threaded member 6 can be fastened to one of the nut and the bolt, and the crimped part 32 joined to the external connection part 8 by a caulking structure. Characterized in that it has.

The screw member 6 included in the sealed battery 20 of the present embodiment may further include a flange portion 33 having a first surface 37 facing the outside and a second surface 38 facing the inside.
Further, the sealed battery 20 of the present embodiment may further include a resin member 15 that covers a boundary portion between the external connection portion 8 and the caulking portion 32.
The sealed battery 20 of the present embodiment may further include an external connection metal plate 45 that is an external wiring that is electrically connected to the external connection portion 8 and that has an opening 46.
Hereinafter, the sealed battery of this embodiment will be described.

1. Sealed battery The sealed battery 20 of the present embodiment is a battery having a sealed structure, such as a lithium ion secondary battery, a nickel / hydrogen secondary battery, or a nickel / cadmium secondary battery.

2. Power Generation Element The power generation element 12 includes a positive electrode 21 and a negative electrode 22 arranged with a separator 24 interposed therebetween. The power generation element 12 may include positive electrodes 21 and negative electrodes 22 that are alternately arranged via separators 24. The power generation element 12 may have a stack structure as shown in FIG. 2 or may have a wound structure. The positive electrode 21 may have a structure in which the positive electrode active material layer 25 is formed on the positive electrode current collector 27. The negative electrode 22 may have a structure in which the negative electrode active material layer 26 is formed on the negative electrode current collector 28.
The power generation element 12 performs a battery reaction together with the electrolyte filled in the case. By this battery reaction, the sealed battery of this embodiment can be discharged and charged.

  The positive electrode 21 and the negative electrode 22 may be plural. In this case, a plurality of positive electrodes 21 and a plurality of negative electrodes 22 may be alternately arranged via separators 24 as shown in FIG. In this case, the positive electrode current collectors 27 of the plurality of positive electrodes 21 can be bundled and joined to the positive electrode connection terminal 3 at the end where the positive electrode active material layer 25 is not formed. The negative electrode current collectors 28 of the plurality of negative electrodes 22 can be bundled and joined to the negative electrode connection terminal 4 at the end where the negative electrode active material layer 26 is not formed.

The positive electrode current collector 27 is not particularly limited as long as it has electrical conductivity and can have the positive electrode active material layer 25 on the surface. For example, the positive electrode current collector 27 is a metal foil. Aluminum foil is preferable. Further, the positive electrode current collector 27 may have a sheet shape, and the positive electrode active material layer 25 may be formed on both surfaces of the positive electrode current collector 27.
The positive electrode active material layer 25 can be formed on the positive electrode current collector 27 by a coating method by adding a conductive agent, a binder or the like to the positive electrode active material. For example, in the case of a lithium secondary battery, the positive electrode active material is LiCoO ₂ , LiNiO ₂ , LiMn ₂ O ₄ or LiFePO ₄ .

Although it will not specifically limit if the negative electrode collector 28 has electrical conductivity and can provide the negative electrode active material layer 26 on the surface, For example, it is metal foil. Copper foil is preferred. The negative electrode current collector 28 may be in the form of a sheet, and the negative electrode active material layer 26 may be formed on both surfaces of the negative electrode current collector 28.
The negative electrode active material layer 26 can be formed on the negative electrode current collector 28 by adding a conductive agent, a binder, or the like to the negative electrode active material and applying it. For example, in the case of a lithium secondary battery, the negative electrode active material is graphite.
The material of the separator 24 is, for example, a polyolefin microporous film.
In addition, for example, when the sealed battery 20 is a lithium ion secondary battery, the electrolyte solution is obtained by dissolving lithium salt solutes such as LiCF ₃ SO ₃ , LiAsF ₆ , LiClO ₄ , LiBF ₄ , and LiPF ₆ as an electrolyte in an organic solvent. A solution can be used.

3. Case Case 1 is a case having a power generation element 12, a positive electrode connection terminal 3, a negative electrode connection terminal 4, and an electrolytic solution therein, and is not particularly limited as long as it is joined to the lid member 2.
The material of the case 1 is not particularly limited as long as it is a material that does not greatly deform even if the power generation element 12, the positive electrode connection terminal 3, the negative electrode connection terminal 4, and the electrolytic solution are accommodated therein. Stainless steel, hard plastic, etc.

4). Lid member The lid member 2 is not particularly limited as long as it is joined to the case 1 so that the electrolyte does not leak, and is joined to the positive electrode connection terminal 3 and the negative electrode connection terminal 4 via the insulating member 10.
A method for joining the lid member 2 and the case 1 is not particularly limited, and for example, joining by laser welding, resistance welding, ultrasonic welding, an adhesive, or the like.
The material of the lid member 2 is not particularly limited as long as it is a material that does not greatly deform even when the lid member 2 and the case 1 are joined, and examples thereof include stainless steel, iron, and hard plastic.

5. Positive connection terminal and negative connection terminal The positive connection terminal 3 is connected to the positive electrode 21 inside the battery, penetrates the lid member 2 and is joined to the lid member 2 via the insulating member 10. Further, the negative electrode connection terminal 4 is connected to the negative electrode 22 inside the battery, penetrates the lid member 2, and is joined to the lid member 2 via the insulating member 10.
With this configuration, each of the positive electrode connection terminal 3 and the negative electrode connection terminal 4 can have a portion connected to the power generation element and a portion connected to the external wiring as a single member, and the electric resistance inside the battery such as contact resistance Can be small. Moreover, since the path | route from the electric power generation element 12 to external wiring can be shortened, the electrical resistance inside a battery can be made small. Furthermore, the number of parts in the connection terminal portion of the battery can be reduced, and the manufacturing cost can be reduced.

Further, the positive electrode connection terminal 3 and the negative electrode connection terminal 4 partition the outside and the inside of the case 1 joined to the lid member 2 and have an outer side surface 17 facing the outside and an inner side surface 18 facing the inside. External connection portions 8.
With this configuration, the positive electrode connection terminal 3 and the negative electrode connection terminal 4 can be formed by processing metal plates, and the manufacturing cost of the connection terminals can be reduced. Further, the battery can be reduced in weight. Furthermore, the overlapping part between the lid member 2 that partitions the inside of the battery and the outside of the battery and the external connection portion 8 of the positive electrode connection terminal 3 or the external connection portion 8 of the negative electrode connection terminal 4 can be eliminated, thereby reducing the manufacturing cost and reducing the battery weight. Can be achieved.

Moreover, the external connection part 8 is joined to the screw member 6 that penetrates a part thereof by a caulking structure.
With this configuration, the external connection portion 8 and the external connection metal plate 45 can be adhered and fixed by the screw member 6 and the corresponding bolt or nut. The external connection portion 8 may be plastically deformed in accordance with the shape of the screw member 6 even if it is not plastically deformed at the portion to be joined to the screw member 6, but it is preferable that the external connection portion 8 is plastically deformed. Since the external connection portion 8 is plastically deformed according to the shape of the screw member 6, the contact area between the external connection portion 8 and the screw member 6 can be increased. This can improve the sealing performance of the battery, and can further prevent the screw member 6 from rotating together when the screw portion 31 of the screw member 6 and the corresponding bolt or nut are fastened together. it can.

Further, the positive electrode connecting terminal 3 and the negative electrode connecting terminal 4 have a positive electrode connecting portion 13 connected to the positive electrode 21 and a negative electrode connecting portion 14 connected to the negative electrode 22, respectively.
Although the shape of the positive electrode connection part 13 and the negative electrode connection part 14 is not specifically limited, For example, it can be set as the shape which bent the short side of the strip-shaped metal plate to the U shape. As a result, the positive electrode 21 or the negative electrode 22 can be connected to both sides of the opposing portion of the U-shaped metal plate. In this case, the length of the long side of the positive electrode connecting portion or the negative electrode connecting portion can be set to 5 to 10 cm, for example.

  The material of the positive electrode connection terminal 3 or the negative electrode connection terminal 4 is not particularly limited as long as it has electrical conductivity and has a strength that does not greatly deform even when the power generation element 12 is connected and accommodated in the case 1. The terminal 3 or the negative electrode connection terminal 4 is obtained by processing a metal plate, preferably the positive electrode connection terminal 3 is obtained by processing an aluminum plate, and the negative electrode connection terminal 4 is obtained by processing a copper plate. Further, the positive electrode connection terminal 3 or the negative electrode connection terminal 4 can be formed without pressing a plurality of metal plates by performing press working or the like on one metal plate.

  Moreover, since the external connection part 8 has the outer side surface 17, it can be made to contact the external connection metal plate 45 by the outer side surface 17. FIG. As a result, the power generation element 12 and the external wiring can be electrically connected via the positive electrode connection terminal 3 and the negative electrode connection terminal 4. As a result, the power generation element 12 can be discharged and charged.

  Moreover, the external connection part 8 can be made into the shape which one side swelled, for example, the shape like the track | truck of a sports field, and the shape which rounded the front-end | tip part of the teardrop shape. In this case, the screw member 6 can be joined to the circular center portion of the circular portion of the external connection portion 8. Further, in this case, the external connection metal plate 45 can have a portion having substantially the same radius of curvature as the circular portion of the external connection portion, and can have an opening 46 at the center of the circle. By setting it as such a structure, the contact area of the external connection part 8 and the external connection metal plate 45 can fully be ensured. In addition, the probability of leakage current flowing between the external connection metal plate 45 and the case 1 or the lid member 2 can be reduced. Moreover, the external connection part 8 and the external connection metal plate 45 can be brought into closer contact. Furthermore, when fixing the external connection part 8 and the external connection metal plate 45 with a nut or bolt corresponding to the screw part 31 of the screw member 6, it is possible to prevent the external connection part 8 from rotating with the rotation of the nut or bolt. it can. This can prevent breakage of the insulating member 10, separation of the joined portion of the insulating member 10 and the lid member 2, and separation of the insulating member 10 from the positive electrode connection terminal 3 or the negative electrode connection terminal 4, and leakage of the electrolyte solution Can be prevented.

  Further, the outer side surface 17 of the external connection portion 8 is provided at a height at which the plate member does not contact the lid member 2 and the case 1 when the outer side surface 17 is brought into contact with a plate member sufficiently wider than the lid member 2 and the case 1. May be. With this configuration, it is possible to prevent leakage current between the external connection metal plate 45 and the lid member 2 or the case 1.

6). Insulating Member The insulating member 10 joins the lid member 2 to the positive electrode connection terminal 3 or the negative electrode connection terminal 4 penetrating the lid member 2. With this configuration, the lid member 2 and the positive electrode connection terminal 3 or the negative electrode connection terminal 4 can be insulated, and leakage current can be prevented from flowing. Further, the gap between the positive electrode connection terminal 3 or the negative electrode connection terminal 4 and the lid member 2 can be closed, and leakage of the electrolyte can be prevented.
The insulating member 10 can join the positive electrode connecting terminal 3 or the negative electrode connecting terminal 4 and the lid member 2 so that the electrolyte does not leak and electrically insulate them, and has resistance to the electrolyte, The positive electrode connection terminal 3 or the negative electrode connection terminal 4 and the lid member 2 are not particularly limited as long as they can be bonded sufficiently strongly. For example, polyphenylene sulfide (PPS) resin and aramid resin.

  Although the formation method of the insulating member 10 is not specifically limited, For example, it can form by injection molding. Further, before the insulating member 10 is formed, the positive electrode connecting terminal 3, the negative electrode connecting terminal 4, and the portion of the lid member 2 that contacts the insulating member 10 can be surface-treated, for example, with a basic aqueous solution. Thereby, joining with the insulating member 10 can be strengthened, and the sealing performance of the battery can be improved. Further, when the threaded portion 31 of the screw member 6 and the bolt or nut corresponding thereto are fastened, a force is applied to the insulating member 10 at the interface between the insulating member 10 and the lid member 2, the positive electrode connection terminal 3 or the negative electrode connection terminal 4. It is possible to prevent peeling and loss of sealing performance.

7). Screw member The screw member 6 penetrates the external connection portion 8 and is joined to the external connection portion 8 by a caulking structure. Further, the screw member 6 includes a screw portion 31 that can be fastened with either a nut outside the battery or a bolt outside the battery, and a crimping portion 32 that is joined to the external connection portion 8.
By having this configuration, the screw member 6 having the screw portion 31 can be fixed to the external connection portion 8. Further, the external connection metal plate 45 is brought into contact with the external connection portion 8, and the external connection metal plate 45 and the external connection portion 8 are connected by tightening the screw portion 31 of the screw member 6 with the corresponding bolt or nut. It can be closely attached and fixed.

  Further, the screw member 6 may have a flange portion 33 having a first surface 37 on the battery outer side and a second surface 38 on the battery inner side. With this configuration, when the caulking portion 32 of the screw member 6 and the external connection portion 8 are joined by the caulking structure, a force can be applied to the first surface 37 of the flange portion 33. As a result, the crimping portion 32 and the external connection portion 8 can be easily joined, and plastic deformation of the screw portion 31 can be prevented.

The screw portion 31 may have a male screw structure and may be provided on the first surface 37, and the crimping portion 32 may be provided on the second surface 38.
The screw member 6 in which the screw portion 31 has a male screw structure is shaped, for example, as shown in the schematic perspective view of FIG. 3 (a) and the schematic side view of FIG. 3 (b) before joining to the external connection portion 8. It may have a cross section as shown in FIG. Further, the screw member 6 may have a cross section as shown in FIG.
By having such a configuration, the threaded portion 31 of the external thread structure can be fastened with a nut outside the battery. Further, the caulking portion 32 can be plastically deformed and joined to the external connection portion 8 by caulking the bolt head or the flange portion 33 and the caulking portion 32 in a raw rivet state.

The screw portion 31 may be a portion having a female screw structure provided in the screw member 6, the flange portion 33 is provided at one end of the screw member 6, and the crimping portion 32 is the other end of the screw member 6. It may be provided at the end.
The screw member 6 in which the screw portion 31 has a female screw structure is shaped, for example, as shown in the schematic perspective view of FIG. 4A and the schematic side view of FIG. And may have a cross section as shown in FIG. 4 (c) or FIG. 4 (d). Further, the screw member 6 may have a cross section as shown in FIG. When the screw member has a cross section as shown in FIGS. 4C and 4F, the caulking portion 32 is covered with the resin member 15 or the like in order to prevent leakage of the electrolyte inside the battery. It is preferable to prevent leakage.

6 (a) and 6 (b) show the process of joining the screw member 6 having the caulking portion 32 in the raw rivet state, the screw portion 31 of the male screw structure and the flange portion 33, and the external connection portion 8 by the caulking structure. It is explanatory drawing. First, for example, as shown in FIG. 6A, the caulking portion 32 of the screw member 6 is fitted into the through hole of the external connection portion 8, and the mold 40 is disposed under the caulking portion 32. Next, as shown in FIG. 6B, the pressing member 41 is pressed against the flange portion 33, and the caulking portion 32 of the screw member 6 is plastically deformed and crimped by the mold 40 and the pressing member 41. At this time, the external connection portion 8 can be plastically deformed so as to be in close contact with the screw member 6 at the same time. Further, a force may be applied between the mold 40 and the pressing member 41 until the first surface 37 of the flange portion 33 is on the same surface as the outer surface 17 of the external connection portion 8 or on the inner side of the battery from the outer surface 17. it can.
In addition, the through-hole which the external connection part 8 before joining with the screw member 6 may have a radius substantially the same as the radius of the outer periphery of the crimping part 32. FIG.
In FIG. 6, the screw member 6 having the male threaded structure 31 has been described. However, the screw member 6 and the external connection section 8 are similarly crimped in the threaded member 6 having the female threaded structure 31. Can be joined.

  Moreover, although the screw member 6 having the flange portion 33 has been described with reference to FIG. 6, the screw member 6 not having the flange portion 33 can be similarly joined to the external connection portion 8 by a caulking structure. However, in this case, in order to caulk the caulking portion 32, it is necessary to apply a force to the head of the screw portion 31 having the male screw structure or one end of the screw portion 31 having the female screw structure. It is necessary to crimp the internal thread structure with a force that does not break. For example, the plastic deformation of the male screw structure or the female screw structure can be prevented by making the caulking portion 32 easier to plastically deform.

The shape of the caulking portion 32 in the raw rivet state is not particularly limited as long as it can be joined to the external connection portion 8 by caulking the caulking portion 32, but may be, for example, a cylindrical shape. By using a cylindrical shape, the caulking portion 32 can be relatively easily plastically deformed. Further, the entire outer peripheral portion can be brought into close contact with the outer peripheral portion after plastic deformation, and leakage of the electrolytic solution can be prevented.
Moreover, the shape of the crimping | crimped part 32 after joining with the external connection part 8 may have the shape expanded, for example to the mouth shape of a trumpet. Moreover, the external connection part 8 may have a shape which closely_contact | adheres to the outer peripheral part of the part expanded in the mouth shape of the trumpet at this time.

  Although the material of the screw member 6 will not be specifically limited if it can have the thread part 31 and the crimp part 32, For example, they are a metal and also steel. Further, by using a metal member for the screw member 6, the screw portion 31, the bolt or nut corresponding to the screw portion 31, the positive electrode connection terminal 3 or the negative electrode connection terminal 4, and the external connection metal plate 45 are all metallic. It can be. As a result, even when the temperature of the battery rises, the bolts and nuts can be prevented from loosening, and the contact resistance between the positive connection terminal 3 or the negative connection terminal 4 and the external connection metal plate 45 increases. Can be prevented.

The screw member 6 may have a convex portion 35 on the second surface 38, and the external connection portion 8 may have a shape plastically deformed so as to contact the outer peripheral portion of the flange portion 33. The screw member 6 may have a convex portion on the outer peripheral portion of the flange portion 33. Moreover, the convex part may be plural.
For example, the protrusions 35 may be provided as shown in FIGS. 3B and 3D, and the protrusions 35 may be provided as shown in FIGS. 4B and 4E. Moreover, although not shown in figure, you may have a some convex part in the outer peripheral part of the flange part 33. FIG.
With this configuration, the external connection portion 8 is plastically deformed along both the portion where the convex portion is formed and the portion where the convex portion is not formed. Therefore, the contact interface between the screw member 6 and the external connection portion 8 is uneven. can do. That is, the screw member 6 and the external connection portion 8 can be bitten at this portion. Thus, the screw member 6 can be prevented from rotating when the screw portion 31 is tightened with the corresponding bolt or nut. In addition, a sufficient tightening torque can be applied to the bolt and nut, and the external connection portion 8 and the external connection metal plate 45 can be sufficiently adhered to each other.

The first surface 37 of the flange portion 33 may be on the same surface as the outer surface 17 of the external connection portion 8 or on the inner side of the battery than the outer surface 17 of the external connection portion 8. That is, the flange portion 33 may be embedded in the external connection portion 8.
With this configuration, it is possible to eliminate a convex portion other than the screw portion 31 having a male screw structure on the outer surface 17 of the external connection portion 8. Thus, when the bolt is passed through the opening 46 of the external connection metal plate 45 and the external connection metal plate 45 and the external connection portion 8 are fixed by the screw portion 31 and the corresponding bolt or nut, the external connection metal plate The contact area between 45 and the external connection portion 8 can be widened, and the number of components required for this fixing can be reduced.

8). Resin Member The resin member 15 may be provided so as to cover a boundary portion between the external connection portion 8 and the caulking portion 32.
With this configuration, it is possible to prevent the electrolytic solution from leaking from a slight gap between the crimping portion 32 and the external connection portion 8.
The resin member 15 is not particularly limited as long as the electrolytic solution does not leak from a slight gap between the caulking portion 32 and the external connection portion 8 and has resistance to the electrolytic solution. For example, polyphenylene sulfide (PPS) resin and aramid resin.
Although the formation method of the resin member 15 is not specifically limited, For example, you may fix using an anchor effect and may form by injection molding. Further, before the resin member 15 is formed, portions of the external connection portion 8 and the caulking portion 32 that are in contact with the resin member 15 can be subjected to surface treatment, for example, treatment with a basic aqueous solution. As a result, the bonding with the resin member 15 can be made stronger.

9. External Connection Metal Plate The external connection metal plate 45 is an external wiring that is electrically connected to the external connection portion 8 and has an opening 46. The external connection metal plate 45 is fixed so as to contact the external connection portion 8 by passing a bolt through the opening 46 and tightening the screw portion 31 and the corresponding nut or bolt.
For example, the external connection metal plate 45 can have a shape as shown in FIG. Further, for example, as shown in FIG. 5B, the external connection portion 8 and the external connection metal can be obtained by passing the opening 46 through the screw portion 31 of the male screw structure of the screw member 6 and fastening the nut 48 and the screw portion 31 together. The plate 45 can be crimped.
With this configuration, the positive electrode connection terminal 3 or the negative electrode connection terminal 4 and the external wiring can be easily and closely contacted. Moreover, since it can contact with a volt | bolt and a nut, it can also remove easily. Further, even when different types of metals are used for the positive electrode connection terminal 3, the negative electrode connection terminal 4, and the external connection metal plate 45, they can be reliably brought into contact with each other. For example, when the positive electrode connection terminal 3 or the negative electrode connection terminal 4 made of different types of metal is joined to the external wiring by welding, there are problems such as difficulty in welding, welding, and peeling of the weld surface depending on the type of the metal. May occur. Further, welding to copper or aluminum generally used for battery connection terminals is difficult and has low reliability. Such a problem can be avoided by contacting with bolts and nuts.

  The material of the external connection metal plate 45 is not particularly limited, and examples thereof include aluminum, copper, and steel.

Further, the external connection metal plate 45 may have a matte nickel plating layer on the surface.
As a result, it is possible to prevent the contact resistance between the external connection metal plate 45 and the external connection portion 8 from increasing.
In general, in a battery, various metals such as aluminum and copper are used for connection terminals. For this reason, there are many cases where different types of metal interfaces exist in the portion connected to the external wiring. At the interface between the different types of metals, the contact resistance may increase due to the characteristics of the two metals. As a measure for reducing the contact resistance generated at the interface between the external wiring and the connection terminal, it is common to perform gold plating, silver plating or nickel plating on the external wiring. However, since gold plating is expensive, it leads to an increase in manufacturing cost. Silver plating is expensive and oxidatively deteriorates, leading to an increase in manufacturing cost and low stability. Nickel plating has the characteristics of being inexpensive and highly stable. Furthermore, the matte nickel plating can have a smaller contact resistance than the bright nickel plating.
Therefore, by forming a matte nickel plating layer on the external connection metal plate 45, it was possible to suppress an increase in contact resistance when copper or aluminum was used for the connection terminals.

    1: Case 2: Lid member 3: Positive electrode connection terminal 4: Negative electrode connection terminal 6: Screw member 8: External connection part 10: Insulating member 12: Power generation element 13: Positive electrode connection part 14: Negative electrode connection part 15: Resin member 17: Outside surface 18: Inside surface 20: Sealed battery 21: Positive electrode 22: Negative electrode 24: Separator 25: Positive electrode active material layer 26: Negative electrode active material layer 27: Positive electrode current collector 28: Negative electrode current collector 31: Screw part 32: Caulking portion 33: Flange portion 35: Convex portion 37: First surface 38: Second surface 40: Mold 41: Pressing member 45: External connection metal plate 46: Opening 48: Nut

Claims (9)

In the case where the lid member is joined, a positive electrode connecting terminal and a negative electrode connecting terminal joined to the lid member via an insulating member, a separator, a positive electrode and a negative electrode arranged via the separator, an electrolyte solution, With
The positive electrode and the negative electrode are connected to the positive electrode connection terminal and the negative electrode connection terminal, respectively.
The positive electrode connection terminal and the negative electrode connection terminal each have a plate-like external connection portion that penetrates the lid member and partitions the outside and the inside of the case joined to the lid member,
The external connection part is joined to a screw member that penetrates a part of the external connection part,
The sealed battery according to claim 1, wherein the screw member includes a screw part that can be fastened to any one of a nut and a bolt, and a caulking part that is joined to the external connection part by a caulking structure.   The battery according to claim 1, wherein the screw member further includes a flange portion having a first surface facing the outside and a second surface facing the inside. The screw portion has a male screw structure and is provided on the first surface;
The battery according to claim 2, wherein the crimping portion is provided on the second surface. The screw portion is a portion having a female screw structure provided in the screw member,
The flange portion is provided at one end of the screw member,
The battery according to claim 2, wherein the crimping portion is provided at the other end of the screw member. The screw member has a convex portion on the second surface,
The battery according to claim 2, wherein the external connection portion has a shape plastically deformed so as to come into contact with an outer peripheral portion of the flange portion.   The battery according to any one of claims 2 to 5, wherein the first surface is a surface on the same surface as the outer surface facing the outside of the external connection portion or a surface closer to the inside than the outer surface. .   The battery according to claim 1, further comprising a resin member that covers a boundary portion between the external connection portion and the caulking portion. An external connection metal plate electrically connected to the external connection portion and having an opening;
The external connection metal plate is fixed so as to contact the external connection portion by passing a bolt through the opening and tightening the screw portion and a corresponding nut or bolt.
The battery according to claim 1, wherein the external connection metal plate has a matte nickel plating layer on the surface. The positive electrode has a positive electrode active material layer containing lithium,
The negative electrode has a negative electrode active material layer containing graphite,
The battery according to claim 1, wherein the electrolytic solution is a solution in which a lithium salt solute is dissolved in an organic solvent.

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