JP2017130435A - Electrochemical cell - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a button-type electrochemical cell having high reliability and high energy density.SOLUTION: A battery 1 includes: an electrode body 10 including a positive electrode body 11 and a negative electrode body 12; and an exterior body 20 in which the electrode body 10 is housed. The exterior body 20 includes: a first container 21 formed in a bottomed cylindrical shape and including a first circumferential wall section 21b; a second container 25 formed in a bottomed cylindrical shape, including a second circumferential wall section 25b surrounding the first circumferential wall section 21b, and housing the electrode body 10 between the second container and the first container 21; and a fusing member 29 interposed between the first circumferential wall section 21b and the second circumferential wall section 25b and fused to the first circumferential wall section 21b and the second circumferential wall section 25b.SELECTED DRAWING: Figure 2

Description

  The present invention relates to an electrochemical cell.

  Some electrochemical cells such as non-aqueous electrolyte secondary batteries and electric double layer capacitors are formed in a button shape (hereinafter also including a coin shape and a cylinder shape). Button-type electrochemical cells are used as power sources for various devices. As one form of the button-type electrochemical cell, for example, a battery as disclosed in Patent Document 1 has been proposed.

  Patent Document 1 discloses a configuration in which a metal negative electrode case also serving as a negative electrode terminal and a metal positive electrode case also serving as a positive electrode terminal are fitted via an insulating gasket. Specifically, in Patent Document 1, the positive electrode case is fitted to the negative electrode case via an insulating gasket by caulking. In the inner space defined by the positive electrode case and the negative electrode case, the electrode body is included together with the nonaqueous electrolyte.

JP 2002-298803 A

However, when the negative electrode case and the positive electrode case are caulked, the negative electrode case and the positive electrode case may be damaged due to the caulking load acting on each case during the caulking process, and the airtightness inside the battery may be reduced. In addition, if caulking is performed with foreign matter sandwiched between the cases, a gap may be formed between the negative electrode case and the positive electrode case due to the foreign matter, which may reduce the airtightness inside the battery.
Further, when sealing between the cases by caulking, it is necessary to give the negative electrode case and the positive electrode case strong enough to withstand the caulking load in order to mechanically improve the airtightness. For this reason, the thickness of a negative electrode case and a positive electrode case increases, the effective volume which accommodates an electrode body reduces, and an energy density becomes small. Therefore, in the conventional electrochemical cell, there is room for improvement in terms of improving airtightness, improving reliability, and improving energy density.

  Therefore, the present invention provides a button-type electrochemical cell with high reliability and high energy density.

The electrochemical cell of the present invention includes an electrode body including a positive electrode body and a negative electrode body, and an exterior body that accommodates the electrode body, and the exterior body is formed in a bottomed cylindrical shape, and includes a first peripheral wall portion. A second container that is formed in a bottomed cylindrical shape, has a second peripheral wall that surrounds the first peripheral wall, and accommodates the electrode body between the first container, And a fusion member interposed between the first peripheral wall portion and the second peripheral wall portion and fused to the first peripheral wall portion and the second peripheral wall portion.
According to the present invention, the gap between the first container and the second container in which the electrode body is accommodated can be sealed without caulking. At this time, even when there is a flaw in the fusion surface with the fusion member in each peripheral wall portion or when a foreign object is sandwiched between the first peripheral wall portion and the second peripheral wall portion, it melted at the time of fusion. The fusing member can fill the periphery of scratches and foreign matters. Thereby, compared with the structure which forms an exterior body by the crimping process of a 1st container and a 2nd container, the airtightness inside an electrochemical cell can be improved.
In addition, when the exterior body is formed by caulking processing between the first container and the second container, the first container and the second container are provided with a strength sufficient to withstand the caulking of the first container and the second container. It is necessary to ensure a thickness equal to or greater than a predetermined value. According to the present invention, since the space between the first container and the second container is sealed with the fusion member, the exterior body is formed by caulking between the first container and the second container. As compared with the first container, the first container and the second container can be made thinner. Thereby, the volume inside an exterior body can be ensured large, and the energy density of an electrochemical cell can be improved.
Therefore, a button-type electrochemical cell with high reliability and high energy density can be provided.

In the above electrochemical cell, it is desirable that the first container is formed of a metal material, and the second container is formed of a laminate film containing a metal material and a resin material.
According to this invention, since the 2nd container is formed with the laminate film, an electrochemical cell can be reduced in weight compared with the structure in which a 1st container and a 2nd container are formed with a metal material. In addition, since the first peripheral wall portion is formed of a metal material, the second peripheral wall portion surrounding the first peripheral wall portion is heated by a heating unit or the like when the fusion member is fused to the first peripheral wall portion and the second peripheral wall portion. When pressing from the outside, the second peripheral wall can be supported by the first peripheral wall. Therefore, the electrochemical cell can be easily manufactured in a desired outer shape.

In the electrochemical cell, a through hole is formed in a bottom wall portion of the second container, and an electrode terminal that is electrically connected to one of the positive electrode body and the negative electrode body is inserted into the through hole. It is desirable.
According to the present invention, since the electrode terminal that is electrically connected to one of the positive electrode body and the negative electrode body is inserted into the through-hole penetrating the second container, either the positive electrode body or the negative electrode body is attached to the exterior body. It is possible to easily conduct to external lead wires. Therefore, in an electrochemical cell using a laminate film for the exterior body, it is possible to realize a configuration in which the interior and exterior of the exterior body are conducted.

In the above electrochemical cell, the inner peripheral surface of the through hole is preferably covered with an insulating material.
Since the second container is formed of a laminate film, the metal material may be exposed on the inner peripheral surface of the through hole. According to the present invention, since the inner peripheral surface of the through hole is covered with the insulating material, it is possible to prevent the electrode terminal inserted through the through hole from being short-circuited with the metal material constituting the second container. Moreover, it can suppress that the metal material which comprises a 2nd container is exposed outside, and can suppress corrosion of a metal material. Therefore, the reliability of the electrochemical cell can be improved.

In the above electrochemical cell, it is preferable that the electrode terminal includes a flange portion disposed to face an inner surface of the bottom wall portion of the second container.
According to the present invention, the distance of the path from the outside of the exterior body to the inside of the exterior body through the through hole can be increased as compared with the configuration in which the electrode terminal does not include the flange portion. Thereby, the amount of moisture entering the interior of the exterior body through the through hole can be reduced. Therefore, the reliability of the electrochemical cell can be improved.

In the above electrochemical cell, it is desirable that an external terminal member that is electrically connected to the electrode terminal is provided outside the exterior body.
According to the present invention, an external terminal member is formed of a metal material such as SUS that can be easily joined to an external lead wire or the like, so that the electrode terminal is difficult to join such as soldering such as aluminum. Can be formed. Therefore, the material selection of the electrode terminal can be easily performed.

Said electrochemical cell WHEREIN: The said electrode terminal is provided with the axial part extended so that the axial direction of the said 2nd container may be followed in the said exterior body, and any one of the said positive electrode body and the said negative electrode body is provided in the said axial part. It is desirable that one of them is conducted and the electrode body is wound.
According to the present invention, since the shaft portion can be used as the core of the electrode body, the number of parts can be reduced as compared with a configuration using a core separate from the electrode terminal. In addition, since one of the positive electrode body and the negative electrode body is electrically connected to the shaft portion, either the positive electrode body or the negative electrode body can be electrically connected to the electrode terminal without using a separate member. The score can be reduced. Therefore, a low-cost electrochemical cell can be obtained.

In the above electrochemical cell, it is desirable that the first peripheral wall portion includes an inner peripheral wall portion and an outer peripheral wall portion surrounding the inner peripheral wall portion.
According to the present invention, the strength of the first peripheral wall portion can be improved as compared with the case where the first peripheral wall portion is configured by one peripheral wall portion. Thereby, compared with the case where a 1st surrounding wall part is comprised by one surrounding wall part, when fusing a fusion member to a 1st surrounding wall part and a 2nd surrounding wall part, a 2nd surrounding wall part is a 1st surrounding wall. It can be strongly pressed toward the part. Therefore, the fusion member can be more reliably fused to the first peripheral wall portion and the second peripheral wall portion, and the airtightness inside the electrochemical cell can be improved. Further, it is possible to improve work efficiency and yield when the fusion member is fused to the first peripheral wall portion and the second peripheral wall portion.

In the electrochemical cell, the first peripheral wall portion includes a connection portion that connects the inner peripheral wall portion and the outer peripheral wall portion over the entire circumference, and the connection portion has a thickness of the first peripheral wall portion. It is desirable to extend along the direction.
According to the present invention, when an external force in the thickness direction acts on the first peripheral wall portion, the connecting portion can function like a rib, and deformation of the first peripheral wall portion can be suppressed. Therefore, the strength of the first peripheral wall portion with respect to the external force in the thickness direction of the first peripheral wall portion can be improved. Accordingly, when the fusion member is fused to the first peripheral wall portion and the second peripheral wall portion, the second peripheral wall portion can be strongly pressed toward the first peripheral wall portion. Therefore, the fusion member can be more reliably fused to the first peripheral wall portion and the second peripheral wall portion, and the airtightness inside the electrochemical cell can be improved. Further, it is possible to improve work efficiency and yield when the fusion member is fused to the first peripheral wall portion and the second peripheral wall portion.

In the above electrochemical cell, the electrode body is formed by laminating the positive electrode body and the negative electrode body, and the electrode body intersects the lamination direction with respect to the laminated portion of the positive electrode body and the negative electrode body. It is desirable to have a tab protruding in the direction.
According to the present invention, the positive electrode body and the negative electrode body can be easily conducted to the other member via the tab by drawing the tab inside the exterior body. Therefore, the structure inside the exterior body can be prevented from becoming complicated, and a low-cost electrochemical cell can be obtained.

  According to the present invention, a button-type electrochemical cell with high reliability and high energy density can be provided.

1 is a perspective view of a battery according to a first embodiment. It is a disassembled perspective view of the battery which concerns on 1st Embodiment. It is explanatory drawing of the formation method of the positive electrode body which concerns on 1st Embodiment, and is a top view of a positive electrode sheet. It is an enlarged side view in the opening part vicinity of the 2nd container which concerns on 1st Embodiment. It is a perspective view explaining the formation method of the exterior body concerning a 1st embodiment. It is a perspective view of the electrode body which concerns on the 1st modification of 1st Embodiment. It is a perspective view of the electrode body which concerns on the 2nd modification of 1st Embodiment. It is a perspective view of the electrode body which concerns on the 3rd modification of 1st Embodiment. It is a perspective view of the electrode terminal which concerns on the 4th modification of 1st Embodiment. It is a perspective view of the electrode terminal which concerns on the 5th modification of 1st Embodiment. It is a perspective view of the electrode terminal which concerns on the 6th modification of 1st Embodiment. It is a perspective view of the battery which concerns on the 7th modification of 1st Embodiment. It is a perspective view of the 2nd container concerning the 8th modification of a 1st embodiment. It is a perspective view of the battery which concerns on 2nd Embodiment. It is a perspective view of the electrode terminal which concerns on 2nd Embodiment. It is a perspective view of the electrode terminal which concerns on 2nd Embodiment. It is a perspective view of the electrode terminal which concerns on the 1st modification of 2nd Embodiment. It is a perspective view of the electrode terminal which concerns on the 2nd modification of 2nd Embodiment. It is a perspective view of the electrode terminal which concerns on the 3rd modification of 2nd Embodiment. It is a perspective view of the electrode terminal which concerns on the 4th modification of 2nd Embodiment. It is a perspective view of the battery which concerns on the 5th modification of 2nd Embodiment. It is a perspective view of the battery which concerns on 3rd Embodiment. It is a disassembled perspective view of the electrode body which concerns on 3rd Embodiment. It is a perspective view of the battery which concerns on 4th Embodiment. It is a disassembled perspective view of the battery which concerns on 4th Embodiment. It is a perspective view of the battery which concerns on the modification of 4th Embodiment. It is sectional drawing of the 1st container which concerns on 5th Embodiment.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following description, as a button-shaped, coin-shaped or cylinder-shaped electrochemical cell formed in a cylindrical shape, a lithium ion secondary battery (hereinafter simply referred to as “battery”) which is a kind of non-aqueous electrolyte secondary battery. )) As an example.

[First Embodiment]
First, the battery 1 according to the first embodiment will be described.
FIG. 1 is a perspective view of the battery according to the first embodiment. FIG. 2 is an exploded perspective view of the battery according to the first embodiment.
As shown in FIGS. 1 and 2, the battery 1 is a so-called button-type battery, and includes an electrode body 10 including a positive electrode body 11 and a negative electrode body 12, and an exterior body 20 in which the electrode body 10 is accommodated. Mainly prepared.

  As shown in FIG. 2, the electrode body 10 is formed in a columnar shape in which a belt-like positive electrode body 11 and a negative electrode body 12 are overlapped and wound. Specifically, the electrode body 10 has a structure in which a belt-like positive electrode body 11 and a negative electrode body 12 are wound around a winding axis P in a state where they are stacked via a separator (not shown). Any of the positive electrode body 11, the negative electrode body 12, and the separator may be disposed on the outermost periphery of the electrode body 10. The electrode body 10 may include a winding core used for winding the positive electrode body 11 and the negative electrode body 12 on the winding axis P.

  The electrode body 10 includes a positive electrode tab 13 (tab) and a negative electrode tab 14 (tab). Each tab 13, 14 intersects in the stacking direction (direction perpendicular to the winding axis P) from the outer peripheral portion of the positive electrode body 11 and the negative electrode body 12 with respect to the stacked portion of the positive electrode body 11 and the negative electrode body 12 ( In the example shown in the figure, each protrudes on one side of the winding axis P). The positive electrode tab 13 is formed integrally with the positive electrode current collector of the positive electrode body 11 and is electrically connected to the positive electrode body 11. The negative electrode tab 14 is formed integrally with the negative electrode current collector of the negative electrode body 12 and is electrically connected to the negative electrode body 12.

FIG. 3 is an explanatory diagram of the method for forming the positive electrode body according to the first embodiment, and is a plan view of the positive electrode sheet.
As shown in FIG. 3, the positive electrode body 11 is formed by punching out a positive electrode sheet 15 in which a positive electrode 11b containing a positive electrode active material is arranged with a certain width on the surface of a metal foil to be a positive electrode current collector 11a. Is done. At this time, a portion of the positive electrode sheet 15 where the positive electrode 11b is disposed is punched into a band shape, thereby forming the positive electrode body 11 in which the positive electrode 11b is disposed on the surface of the positive electrode current collector 11a. Furthermore, a positive electrode tab 13 that protrudes from the positive electrode body 11 and is electrically connected to the positive electrode current collector 11 a can be formed by punching out the region of the positive electrode sheet 15 where the positive electrode 11 b is not disposed together with the positive electrode body 11. The method for forming the negative electrode body 12 is the same as the method for forming the positive electrode body 11.

  In the present embodiment, each of the tabs 13 and 14 is formed integrally with the current collector. However, the present invention is not limited to this, and the tabs 13 and 14 are formed separately from the current collector and welded to the current collector. May be attached. In this case, the positive electrode tab is preferably formed of a metal material such as aluminum. The negative electrode tab is preferably formed of a metal material such as SUS, nickel, or copper. Further, in this case, it is preferable to attach an insulating tape to the surface of each tab so as to cover the end face of each tab or a flash generated by welding, and to prevent each tab from damaging other members. . When the positive electrode tab and the negative electrode tab are formed separately from the current collector, each tab can be formed of a material thicker than the metal foil that forms the current collector. Thereby, the positive electrode tab and the negative electrode tab are not easily broken, and the reliability is improved.

  As shown in FIG. 2, the exterior body 20 includes a bottomed cylindrical first container 21, a bottomed cylindrical second container 25, and a cylindrical fusion member 29. The first container 21, the second container 25, and the fusion member 29 are arranged so that their central axes are coaxial. Hereinafter, the central axis of the first container 21, the second container 25, and the fusion member 29 is referred to as the central axis O, the direction along the central axis O is referred to as the axial direction, and the direction orthogonal to the central axis O is referred to as the radial direction. The direction around the central axis O is called the circumferential direction. In the following description, in the axial direction, a direction toward the center of the battery 1 may be referred to as an inner side, and a direction away from the center of the battery 1 (a direction toward the first container 21 and the second container 25) may be referred to as an outer side. .

The first container 21 is made of a conductive metal material. As a material for forming the first container 21, for example, SUS, a clad material made of iron and nickel, and the like can be used, and SUS is more preferable in terms of excellent durability.
The first container 21 includes a first bottom wall portion 21a and a first peripheral wall portion 21b. The first container 21 is open on the second container 25 side in the axial direction. The dimension of the first container 21 is such that the electrode body 10 can be disposed on the inner side so that the winding axis P is coaxial with the central axis O. The negative electrode tab 14 is connected to the inner surface of the first container 21 by welding or the like. Thereby, the first container 21 functions as a negative electrode terminal of the battery 1.

  The second container 25 is formed of a laminate film. The laminate film is formed by laminating a metal foil, a resin fusion layer constituting the inner surface of the second container 25, and a resin protective layer constituting the outer surface. The fusing layer is formed using, for example, a thermoplastic resin such as polyolefin polyethylene or polypropylene. The following materials can be appropriately selected as the polyolefin. Examples of the polyolefin include, for example, a high pressure method low density polyethylene (LDPE), a low pressure method high density polyethylene (HDPE), an inflation polypropylene (IPP) film, an unstretched polypropylene (CPP) film, a biaxially stretched polypropylene (OPP) film, and a straight chain. Any material of linear short-chain branched polyethylene (L-LDPE, metallocene catalyst specification) can be used. The protective layer is formed using, for example, the above-described polyolefin, polyester such as polyethylene terephthalate, nylon, or the like. The fusing layer and the protective layer are each bonded to the metal foil by heat fusing or an adhesive via a bonding layer.

The second container 25 includes a second bottom wall portion 25a and a second peripheral wall portion 25b. The second container 25 is formed so that the dimension in the axial direction is equivalent to that of the first container 21. The inner diameter of the second peripheral wall portion 25 b is slightly larger than the outer diameter of the first peripheral wall portion 21 b of the first container 21. The second container 25 is open on the first container 21 side in the axial direction. That is, the second container 25 accommodates the first container 21 with the first container 21 and the openings facing each other in the axial direction. The second peripheral wall portion 25b surrounds the first peripheral wall portion 21b. Between the first container 21 and the second container 25 (i.e., inside the exterior body 20), an accommodating part in which the electrode body 10 is accommodated is a first bottom wall part 21a, a first peripheral wall part 21b, and a second bottom. It is defined by the wall portion 25a.
A through hole 26 is formed in the second bottom wall portion 25 a of the second container 25. The through hole 26 is formed coaxially with the central axis O.

Ring films 31 and 32 formed in an annular shape are disposed on both surfaces of the second bottom wall portion 25a. Each ring film 31 and 32 is formed of an insulating material. As an insulating material for forming the ring films 31 and 32, for example, a thermoplastic resin such as polyethylene or polypropylene can be used.
The first ring film 31 is disposed on the inner surface of the second bottom wall portion 25a. The first ring film 31 is formed with a first film through hole 31 a coaxial with the through hole 26. The 1st ring film 31 has the cyclic | annular wall part 31b extended toward the outer side of an axial direction from the inner periphery. The outer diameter of the wall portion 31 b is equal to the inner diameter of the through hole 26. The wall portion 31 b is located in the through hole 26.
The 1st ring film 31 is heat-sealed with respect to the inner surface of the 2nd bottom wall part 25a, and has coat | covered the circumference | surroundings of the through-hole 26 among the 2nd bottom wall part 25a from the inner side of an axial direction. The wall portion 31 b covers the inner peripheral surface of the through hole 26 in the through hole 26.

  The second ring film 32 is disposed on the outer surface of the second bottom wall portion 25a. The second ring film 32 has a second film through hole 32 a that is coaxial with the through hole 26. The inner diameter of the second film through hole 32a is equal to the inner diameter of the through hole 26, for example. The second ring film 32 is heat-sealed to the outer surface of the second bottom wall portion 25a, and covers the periphery of the through hole 26 in the second bottom wall portion 25a from the outside in the axial direction.

  The second bottom wall 25a is provided with an electrode terminal 40 for connecting the positive electrode body 11 to an external lead wire or the like. That is, the electrode terminal 40 functions as a positive electrode terminal of the battery 1. The electrode terminal 40 is made of a metal material such as aluminum or an aluminum alloy. The electrode terminal 40 includes a flange portion 41 that is disposed to face the inner surface of the second bottom wall portion 25a in the axial direction, and a lead portion 43 that extends outward in the axial direction from the center of the flange portion 41. Yes.

  The flange portion 41 is disposed coaxially with the central axis O. The outer diameter of the flange portion 41 is smaller than the inner diameter of the first peripheral wall portion 21 b of the first container 21. The flange portion 41 is heat-sealed to the second bottom wall portion 25a with the first ring film 31 interposed therebetween. The positive electrode tab 13 is electrically connected to the flange portion 41, and more preferably connected by welding or the like. In addition, for example, ultrasonic welding, laser welding, resistance welding, or the like can be applied to the welding between the flange portion 41 and the positive electrode tab 13. Moreover, in order to assist an electrical connection between the flange part 41 and the positive electrode tab 13, an electroconductive material may be interposed, and in this case, the flange part 41 and the positive electrode tab 13 interpose a conductive paste. May be connected. Here, since the flange portion 41 and the positive electrode tab 13 are electrically connected to each other, a physical method such as caulking or pressing can be applied to the both.

  The lead portion 43 is formed in a cylindrical shape. The lead portion 43 is inserted into the through hole 26 of the second bottom wall portion 25a. The drawer portion 43 is crimped on the outside of the exterior body 20 (see FIG. 1), and the second bottom wall portion 25a and the ring films 31, 32 are sandwiched between the flange portion 41.

  The fusion member 29 is interposed between the first peripheral wall portion 21 b of the first container 21 and the second peripheral wall portion 25 b of the second container 25. The fusion member 29 is made of a thermoplastic resin such as polyethylene or polypropylene. The fusion member 29 may be formed as a single layer or may be formed by laminating a plurality of resin materials. The fusion member 29 is heat-sealed to the first peripheral wall portion 21b and the second peripheral wall portion 25b. Thereby, the inside (housing part) of the exterior body 20 is sealed with respect to the exterior of the exterior body 20.

FIG. 4 is an enlarged side view in the vicinity of the opening of the second container according to the first embodiment.
As shown in FIG. 4, the fusion member 29 is disposed so that a part thereof is located outside the opening edge of the second peripheral wall portion 25 b of the second container 25. At this time, the fusion | melting member 29 may coat | cover the opening end surface of the 2nd surrounding wall part 25b by the fusion | melting at the time of heat sealing | fusion. Thereby, it can prevent that the metal foil which comprises the laminate film which comprises the 2nd container 25, and the 1st container 21 are short-circuited.

Hereinafter, the formation method of the exterior body 20 is demonstrated with reference to FIG.
First, the electrode terminal 40 is assembled to the second container 25. Specifically, the ring films 31 and 32 are heated and melted in a state where the ring films 31 and 32 and the electrode terminals 40 are arranged at predetermined positions. Thereby, the electrode terminal 40 is heat-sealed to the second container 25 via the ring films 31 and 32. Next, the drawing portion 43 is crimped.

  Next, the electrode body 10 is accommodated inside the first container 21, and the second container 25 is assembled to the first container 21. Specifically, in a state where the fusion member 29 is disposed between the first peripheral wall portion 21b and the second peripheral wall portion 25b, the fusion member 29 is heated and melted, so that the fusion member 29 is moved to the first peripheral wall. It is heat-sealed to the part 21b and the second peripheral wall part 25b.

FIG. 5 is a perspective view illustrating a method for forming an exterior body according to the first embodiment.
As shown in FIG. 5, the heat fusion between the first peripheral wall portion 21 b and the second peripheral wall portion 25 b can be performed by pressing a heated object such as metal or ceramics, more preferably a roll-shaped heating roll. 50. Specifically, the fusion member 29 is melted by pressing the heating roll 50 heated to a temperature at which the fusion member 29 can be melted against the second peripheral wall portion 25b from the outside in the radial direction. Thereafter, the fusion member 29 is cooled, so that the fusion member 29 is thermally fused to the first peripheral wall portion 21b and the second peripheral wall portion 25b. At this time, heat fusion can be performed by sequentially or simultaneously pressing a plurality of heated objects. The heating roll 50 is made of a metal material having a high thermal conductivity, and for example, brass or aluminum can be used. A tape of fluorine resin, silicone resin, polyimide resin or the like may be disposed on the surface of the heating roll 50 to prevent the heated second peripheral wall portion 25b from adhering.

  Note that the fusion member 29 may be in a state of being thermally fused to the first container 21 in advance. In this case, after the fusion member 29 is disposed so as to surround the first peripheral wall portion 21b, the heated heating roll 50 is pressed against the fusion member 29, whereby the fusion member 29 is moved to the first peripheral wall portion. It can be heat-sealed to 21b. In addition, the adhesion of the fusion member 29 can be improved by performing degreasing cleaning on the first peripheral wall portion 21b in advance and performing primer treatment on the fusion member 29.

Thus, in this embodiment, the fusion member 29 is provided between the first peripheral wall portion 21b of the bottomed cylindrical first container 21 and the second peripheral wall portion 25b of the bottomed cylindrical second container 25. And the fusion member 29 is fused to the first peripheral wall portion 21b and the second peripheral wall portion 25b.
According to this configuration, the gap between the first container 21 and the second container 25 in which the electrode body 10 is accommodated can be sealed without caulking. At this time, even when there is a scratch on the fusion surface with the fusion member 29 in each of the peripheral wall portions 21b and 25b, or when foreign matter is sandwiched between the first peripheral wall portion 21b and the second peripheral wall portion 25b, The fusing member 29 melted at the time of heat fusing can fill the periphery of scratches and foreign matters. Thereby, compared with the structure which forms an exterior body by the crimping process of a 1st container and a 2nd container, the airtightness inside the battery 1 can be improved.
In addition, when the exterior body is formed by caulking processing between the first container and the second container, the first container and the second container are provided with a strength sufficient to withstand the caulking of the first container and the second container. It is necessary to secure a thickness of a predetermined value or more. According to the present embodiment, since the space between the first container 21 and the second container 25 is sealed by thermal fusion with the fusion member 29, the exterior body is caulked between the first container and the second container. Compared with the structure formed by processing, the first container 21 and the second container 25 can be made thinner. Thereby, the volume inside the exterior body 20 can be ensured large, and the energy density of the battery 1 can be improved.
Therefore, the button-type battery 1 having high reliability and high energy density can be provided.

  Moreover, since the 2nd container 25 is formed with the laminate film, the battery 1 can be reduced in weight compared with the structure in which a 1st container and a 2nd container are formed with a metal material. Moreover, since the first peripheral wall portion 21b is formed of a metal material, the second peripheral portion surrounding the first peripheral wall portion 21b when the fusion member 29 is thermally fused to the first peripheral wall portion 21b and the second peripheral wall portion 25b. When the peripheral wall 25b is pressed from the outside by the heating roll 50, the second peripheral wall 25b can be supported by the first peripheral wall 21b. Therefore, the battery 1 can be easily manufactured in a desired outer shape.

  Further, since the electrode terminal 40 that conducts with the positive electrode body 11 is inserted into the through hole 26 that penetrates the second container 25, the positive electrode body 11 can be easily conducted with respect to a lead wire or the like outside the exterior body 20. Can do. Therefore, in the battery 1 using the laminate film for the exterior body 20 (second container 25), a configuration in which the inside and outside of the exterior body 20 are electrically connected can be realized.

  Further, since the second container 25 is formed of a laminate film, a metal material (metal foil) may be exposed on the inner peripheral surface of the through hole 26. According to the present embodiment, since the inner peripheral surface of the through hole 26 is covered with the first ring film 31 made of an insulating material, the electrode terminal 40 inserted into the through hole 26 is a metal constituting the second container 25. Short circuit with the foil can be prevented. Moreover, it can suppress that the metal foil which comprises the 2nd container 25 is exposed outside, and can suppress corrosion of metal foil. Therefore, the reliability of the battery 1 can be improved. Although the material of the ring films 31 and 32 may be a single material resin, it is more preferable to use a layered material of two or more kinds of resins. In particular, a non-woven olefin resin can be used as one of the layered resins.

  In addition, since the electrode terminal 40 includes the flange portion 41 disposed to face the inner surface of the second bottom wall portion 25a, the through hole is formed from the outside of the exterior body 20 as compared with the configuration in which the electrode terminal does not include the flange portion. The distance of the route leading to the inside of the exterior body 20 through 26 can be increased. Thereby, the amount of moisture entering the interior of the exterior body 20 through the through hole 26 can be reduced. Therefore, the reliability of the battery 1 can be improved.

  In addition, since the electrode body 10 has the tabs 13 and 14, by drawing the tabs 13 and 14 inside the exterior body 20, the positive electrode body 11 and the negative electrode body 12 and other members (for example, the electrode terminal 40 and the like) The first container 21) can be easily conducted through the tabs 13 and 14. Therefore, the structure inside the exterior body 20 can be prevented from becoming complicated, and the battery 1 can be manufactured at low cost.

  In the first embodiment, the negative electrode body 12 and the first container 21 are electrically connected via the negative electrode tab 14, but the present invention is not limited to this. For example, the negative electrode body 12 and the inner surface of the first container 21 may be electrically connected by disposing the negative electrode current collector of the negative electrode body 12 on the outermost periphery of the electrode body 10.

Moreover, in the said 1st Embodiment, although the positive electrode tab 13 and the negative electrode tab 14 protrude from the outer peripheral part of the positive electrode body 11 and the negative electrode body 12, it is not limited to this.
FIG. 6 is a perspective view of an electrode body according to a first modification of the first embodiment. FIG. 7 is a perspective view of an electrode body according to a second modification of the first embodiment.
As shown in FIG. 6, the positive electrode tab 13 and the negative electrode tab 14 may protrude from the inner peripheral portions of the positive electrode body 11 and the negative electrode body 12. Further, as shown in FIG. 7, one of the positive electrode tab 13 and the negative electrode tab 14 (the positive electrode tab 13 in the illustrated example) may protrude from the inner peripheral portion, and the other may protrude from the outer peripheral portion.

In the first embodiment, and in the first and second modifications, the positive electrode tab 13 and the negative electrode tab 14 protrude from the laminated portion of the positive electrode body 11 and the negative electrode body 12 in the same direction. It is not limited to. The positive electrode tab 13 and the negative electrode tab 14 may protrude from the stacked portions of the positive electrode body 11 and the negative electrode body 12 in different directions (for example, one side and the other side in the axial direction of the winding axis P), respectively.
In addition, the positive electrode tab 13 and the negative electrode tab 14 may be bent in any direction after protruding from the laminated portion of the positive electrode body 11 and the negative electrode body 12 along the axial direction of the winding axis P.

  Moreover, you may combine suitably each modification mentioned above. For example, one of the positive electrode tab 13 and the negative electrode tab 14 protrudes from the inner periphery of the positive electrode body 11 and the negative electrode body 12 to one side in the axial direction of the winding shaft P, and is further bent outward in the radial direction. The other may protrude from the outer periphery of the positive electrode body 11 and the negative electrode body 12 to the other side in the axial direction of the winding shaft P, and may be further bent toward the inner side in the radial direction. Further, one of the positive electrode tab 13 and the negative electrode tab 14 protrudes from the inner peripheral portion of the positive electrode body 11 and the negative electrode body 12 to one side in the axial direction of the winding shaft P, and is further bent toward the inner side in the radial direction. The other may protrude from the inner peripheral part of the positive electrode body 11 and the negative electrode body 12 to the other side in the axial direction of the winding shaft P, and may be further bent toward the inner side in the radial direction.

  In this way, the positive electrode tab 13 and the negative electrode tab 14 are bent toward the inner side in the radial direction, so that the positive electrode tab 13 and the negative electrode tab 14 can be wound around the winding axis P without shortening the positive electrode tab 13 and the negative electrode tab 14. It can be easily formed in a shape that does not protrude from the laminated portion of the positive electrode body 11 and the negative electrode body 12 when viewed from the axial direction.

FIG. 8 is a perspective view of an electrode body according to a third modification of the first embodiment.
Moreover, as shown in FIG. 8, each of the positive electrode tab 13 and the negative electrode tab 14 may be subjected to a plurality of diffraction bends. Specifically, the positive electrode tab 13 protrudes from the outer periphery of the positive electrode body 11 and the negative electrode body 12 to one side in the axial direction of the winding axis P. The positive electrode tab 13 is bent toward the inside in the radial direction at the base end portion, and is bent toward the outside in the radial direction at the intermediate portion. The negative electrode tab 14 protrudes from the outer periphery of the positive electrode body 11 and the negative electrode body 12 to the other side in the axial direction of the winding axis P. The negative electrode tab 14 is bent toward the inside in the radial direction at the base end portion, and is bent toward the outside in the radial direction at the intermediate portion in the extending direction.

  Also, a plurality of positive electrode tabs 13 may be formed and connected to each other by welding or the like. The same applies to the negative electrode tab 14.

Moreover, in the said 1st Embodiment, although the extraction part 43 of the electrode terminal 40 is formed in the cylindrical shape, it is not limited to this.
FIG. 9 is a perspective view of an electrode terminal according to a fourth modification of the first embodiment. FIG. 10 is a perspective view of an electrode terminal according to a fifth modification of the first embodiment. FIG. 11 is a perspective view of an electrode terminal according to a sixth modification of the first embodiment.
As shown in FIG. 9, the drawer part 43 may be formed in the column shape. Further, as shown in FIG. 10, the lead-out portion 43 may be formed in a cylindrical shape, and may be formed in a tapered shape in which the inner peripheral surface on the opening side gradually increases in diameter from the inner side to the outer side in the axial direction. . In addition, as shown in FIG. 11, a plurality of slits 44 may be formed in the drawer portion 43.

FIG. 12 is a perspective view of a battery according to a seventh modification of the first embodiment.
Further, as shown in FIG. 12, the battery 1 may include an external terminal member 5. The external terminal member 5 is formed in a long rectangular plate shape from a metal material such as SUS, nickel, or copper plated with nickel. An insertion hole through which the lead-out portion 43 of the electrode terminal 40 is inserted is formed at one end of the external terminal member 5 in the extending direction. The external terminal member 5 is sandwiched between the crimped drawn portion 43 and the second ring film 32 in a state where the drawn portion 43 is inserted through the insertion hole. Further, the external terminal member 5 is curved in a U shape so that the other end portion in the extending direction covers the tip of the lead portion 43, and the other end portion and the lead portion 43 are connected by welding or the like.

According to this configuration, the external terminal member 5 is formed of a metal material such as SUS that can be easily joined to the external lead wire, so that it is difficult to join the electrode terminal 40 by soldering such as aluminum. It can be formed of a material. Here, in the example shown in FIG. 12, the external terminal member 5 is formed in a U-shape, but it may be formed in a flat plate shape or an L-shape, other than being used for soldering with an external lead wire or the like. Alternatively, the battery 1 may be directly joined to the circuit board of the power supply destination device via the external terminal member 5. In addition, the external terminal member 5 can be screwed to a circuit board, a terminal or the like of a device to which power is supplied. Therefore, the material selection of the electrode terminal 40 can be performed easily.
Furthermore, the external terminal member 5 can also be screwed to the electrode terminal 40 and screwed. Thereby, the workability | operativity at the time of battery replacement | exchange with the apparatus using a battery can be improved.

FIG. 13 is a perspective view of a second container according to an eighth modification of the first embodiment.
Further, as shown in FIG. 13, a groove-shaped weakened portion 27 may be formed in the second container 25. In the illustrated example, the weakening portion 27 is formed in an annular shape so as to be coaxial with the central axis O on the outer surface of the second bottom wall portion 25a.
Thus, by providing the weakened portion 27 in the second container 25 formed of the laminate film, when the gas is generated inside the battery 1 and the internal pressure rises, the exterior body 20 is broken at the weakened portion 27. Thus, the internal pressure can be reduced. That is, the weakening part 27 can be functioned as a safety valve.

[Second Embodiment]
Next, the battery 101 according to the second embodiment will be described.
FIG. 14 is a perspective view of a battery according to the second embodiment.
In the first embodiment shown in FIGS. 1 and 2, the battery 1 is formed in a so-called button shape. On the other hand, in the second embodiment shown in FIG. 14, the battery 101 is different from the first embodiment in that it is formed in a so-called cylinder shape. In addition, about the structure similar to 1st Embodiment shown in FIG.1 and FIG.2, the same code | symbol is attached | subjected and detailed description is abbreviate | omitted (same also about the following embodiment).

  As shown in FIG. 14, the first container 121 is formed so that the dimension in the axial direction is larger than that of the second container 25. The second peripheral wall portion 25 b of the second container 25 surrounds the opening end portion of the first peripheral wall portion 121 b of the first container 121. An electrode terminal 140 is provided on the second bottom wall portion 25 a of the second container 25.

15 and 16 are perspective views of electrode terminals according to the second embodiment.
As shown in FIGS. 14 to 16, the electrode terminal 140 includes a flange portion 41, a lead-out portion 43, and a shaft portion 145. The shaft portion 145 is formed in a columnar shape. Between the 1st container 121 and the 2nd container 25 (accommodating part), it extends toward the opposite side to the drawer | drawing-out part 43 from the center of the flange part 41 along the axial direction. Note that the tip surface of the shaft portion 145 (the surface facing the first bottom wall portion 121a in the axial direction) is spaced apart from the first bottom wall portion 121a in the axial direction. Note that the shaft portion 145 may be formed integrally with the flange portion 41 or may be fitted into a hole provided in the flange portion 41. An electrode body 10 (see FIG. 2) is wound around the shaft portion 145. That is, the shaft portion 145 is used as a winding core of the electrode body 10. A positive electrode current collector of the positive electrode body 11 (see FIG. 2) is connected to the shaft portion 145 by welding or the like to be conductive.

  According to this configuration, since the shaft portion 145 can be used as the core of the electrode body 10, the number of parts can be reduced as compared with a configuration using a core separate from the electrode terminal 140. Further, since the positive electrode body 11 is electrically connected to the shaft portion 145, the positive electrode body 11 and the electrode terminal 140 can be electrically connected without using a separate member (for example, the positive electrode tab 13 shown in FIG. 2). Can be reduced. Therefore, the battery 101 can be manufactured at low cost.

In addition, in the said 2nd Embodiment, although the axial part 145 of the electrode terminal 140 is formed in the column shape, it is not limited to this.
FIG. 17 is a perspective view of an electrode terminal according to a first modification of the second embodiment. FIG. 18 is a perspective view of an electrode terminal according to a second modification of the second embodiment. FIG. 19 is a perspective view of an electrode terminal according to a third modification of the second embodiment. FIG. 20 is a perspective view of an electrode terminal according to a fourth modification of the second embodiment.
As shown in FIG. 17, the shaft portion 145 may be formed in a cylindrical shape. According to this configuration, the electrode terminal 140 can be reduced in weight.
Further, as shown in FIG. 18, the shaft portion 145 may be formed in a cylindrical shape and may include at least one slit 146. In the illustrated example, each slit 146 penetrates the shaft portion 145 in the radial direction and extends in the axial direction. According to this configuration, the positive electrode current collector of the positive electrode body 11 can be sandwiched in the slit 146 when the shaft portion 145 is used as the core of the electrode body 10. Therefore, the positive electrode body 11 and the shaft portion 145 can be electrically connected without welding, and the manufacturing cost of the battery 101 can be reduced. Moreover, as shown in FIG. 19, the slit 146 may be formed in the waveform.

  Further, as shown in FIG. 20, a flat portion 145 a extending in a direction orthogonal to a predetermined radial direction may be formed on a part of the outer peripheral surface of the shaft portion 145. By welding the positive electrode current collector of the positive electrode body 11 to the flat surface portion 145a, the positive electrode body 11 and the shaft portion 145 can be more firmly connected. The shaft portion 145 may have a polygonal cross-sectional shape orthogonal to the axial direction.

Moreover, in the said 2nd Embodiment, although the flange part 41 of the electrode terminal 140 is arrange | positioned facing the inner surface of the 2nd bottom wall part 25a of the 2nd container 25, it is not limited to this.
FIG. 21 is a perspective view of a battery according to a fifth modification of the second embodiment.
As shown in FIG. 21, the flange portion 41 may be disposed to face the outer surface of the second bottom wall portion 25 a of the second container 25. In this case, the second ring film 32 (see FIG. 14) is disposed between the flange portion 41 and the second bottom wall portion 25a, and the flange portion 41 and the second bottom wall are interposed via the second ring film 32. The part 25a is heat-sealed.
According to this configuration, when gas is generated inside the battery 101 and the internal pressure rises, the flange portion 41 is separated from the second bottom wall portion 25a and the through hole 26 (see FIG. 2) is opened, so that the internal pressure is increased. Can be reduced. That is, the flange portion 41 can function as a safety valve.

[Third Embodiment]
Next, the battery 201 according to the third embodiment will be described.
FIG. 22 is a perspective view of a battery according to the third embodiment.
In the first embodiment shown in FIGS. 1 and 2, the battery 1 is formed in a so-called button shape. On the other hand, in the third embodiment shown in FIG. 22, the battery 201 is different from the first embodiment in that it is formed in a so-called coin shape.

FIG. 23 is an exploded perspective view of the electrode body according to the third embodiment.
As shown in FIG. 23, the electrode body 210 is configured by laminating a plurality of positive electrode bodies 211 and negative electrode bodies 212 alternately in the axial direction via a separator (not shown).
The positive electrode 211 is formed in a circular shape when viewed from the axial direction. The positive electrode body 211 includes a positive electrode current collector 211a made of a circular metal foil, and a positive electrode 211b disposed on the surface of the positive electrode current collector 211a.
A part of the positive electrode 211 in the circumferential direction is formed with a notch 211c that is notched linearly in a direction orthogonal to a predetermined radial direction. The positive electrode current collector 211a is integrally formed with a positive electrode tab 213 protruding from the notch 211c. The positive electrode tab 213 protrudes outward in the radial direction (direction intersecting the stacking direction) from one circumferential side of the notch 211c. Therefore, the positive electrode tabs 213 overlap in the axial direction.

The negative electrode body 212 is formed in a circular shape when viewed from the axial direction. The negative electrode body 212 includes a negative electrode current collector 212a made of a circular metal foil, and a negative electrode 212b disposed on the surface of the negative electrode current collector 212a.
A part of the negative electrode body 212 in the circumferential direction is formed with a notch 212c that is notched linearly in a direction orthogonal to a predetermined radial direction. The negative electrode current collector 212a is integrally formed with a negative electrode tab 214 protruding from the notch 212c. The negative electrode tab 214 protrudes radially outward from the other circumferential side of the notch 212c. Therefore, the negative electrode tabs 214 overlap in the axial direction. Furthermore, in the electrode body 210, the positive electrode tab 213 and the negative electrode tab 214 are arranged at positions that do not overlap in the axial direction.

  The positive electrode 211b is disposed inside the outer peripheral edge of the negative electrode 212b when viewed from the axial direction. The positive electrode tabs 213 are connected to each other by welding or the like, and are connected to the flange portion 41 (see FIG. 2) of the electrode terminal 40 to be conductive. The negative electrode tabs 214 are connected to each other by welding or the like, and are connected to the first container 21 (see FIG. 22) and are electrically connected.

  Thus, by forming the electrode body 210 by alternately laminating the positive electrode body 211 and the negative electrode body 212 formed in a circular shape, the axial dimension shown in FIG. 22 is sufficiently smaller than the outer diameter. The electrode body 210 can be accommodated in the exterior body 220 of the formed coin-shaped battery 201.

  Note that the electrode body included in the battery 201 is not limited to the form shown in FIG. The electrode body provided in the battery 201 may be formed in a flat plate shape by compressing an electrode body wound in the same manner as the electrode body 10 shown in FIG. 2 in a direction perpendicular to the winding axis. Thereby, the electrode body can be accommodated in the exterior body 220 of the coin-shaped battery 201.

[Fourth Embodiment]
Next, the battery 301 according to the fourth embodiment will be described.
FIG. 24 is a perspective view of a battery according to the fourth embodiment. FIG. 25 is an exploded perspective view of the battery according to the fourth embodiment.

  In the first embodiment shown in FIGS. 1 and 2, ring films 31 and 32 are provided on both surfaces of the second bottom wall portion 25 a of the second container 25. On the other hand, in the fourth embodiment shown in FIGS. 24 and 25, the first embodiment is that the first ring film 331 is disposed only on the inner surface of the second bottom wall portion 25 a of the second container 25. Is different. In the first embodiment, the first ring film 31 has a wall portion 31 b that covers the inner peripheral surface of the through hole 26. On the other hand, in the fourth embodiment, the first ring film 331 is formed flat along the vertical surface of the central axis O, and does not include a wall portion that covers the inner peripheral surface of the through hole 26. Different from one embodiment. Further, in the seventh modified example of the first embodiment, the electrode terminal 40 including the flange portion 41 and the lead portion 43 that are integrally formed, and the external terminal that is provided outside the exterior body 20 and connected to the lead portion 43. And a member 5. On the other hand, in the fourth embodiment, the electrode terminal 340 corresponding to the flange portion 41 described above and the external terminal member 305 provided outside the exterior body 20 and connected to the electrode terminal 340 are provided. It is different from the embodiment.

  As shown in FIGS. 24 and 25, the first ring film 331 has a first film through hole 331 a coaxial with the through hole 26. The inner diameter of the first film through hole 331 a is smaller than the inner diameter of the through hole 26. The first ring film 331 is heat-sealed to the inner surface of the second bottom wall portion 25a, and covers the periphery of the through hole 26 in the second bottom wall portion 25a from the inner side in the axial direction.

  The electrode terminal 340 is made of a metal material such as aluminum or an aluminum alloy. The electrode terminal 340 is formed in a disk shape and is arranged coaxially with the central axis O. The outer diameter of the electrode terminal 340 is smaller than the inner diameter of the first peripheral wall portion 21 b of the first container 21 and larger than the inner diameter of the through hole 26. The electrode terminal 340 is heat-sealed to the second bottom wall portion 25a with the first ring film 331 interposed therebetween. Thereby, the communication inside and outside of the exterior body 20 through the through hole 26 is blocked. The central portion of the electrode terminal 340 is exposed to the outside in the axial direction through the through hole 26 and the first film through hole 331a. The positive electrode tab 13 is electrically connected to the electrode terminal 340 inside the exterior body 20.

  The external terminal member 305 is a long rectangular plate-shaped metal piece formed of a metal material such as aluminum, nickel, or nickel-plated copper. One end portion of the external terminal member 305 is arranged in a face-to-face manner and electrically connected to the central portion of the electrode terminal 340 exposed to the outside in the axial direction. The external terminal member 305 and the electrode terminal 340 are fixed by, for example, ultrasonic welding, laser welding, resistance welding, or the like. The external terminal member 305 is bent at a substantially right angle in the middle part in the longitudinal direction, and extends so as to be separated from the exterior body 20 along the axial direction. The external terminal member 305 is preferably fixed in advance with respect to the electrode terminal 340 when the battery 301 is assembled.

Thus, according to the present embodiment, the external terminal member 305 is formed of a metal material that can be easily joined to the external lead wire such as soldering, so that the electrode terminal 340 can be joined by soldering such as aluminum. It can be formed from difficult materials. Therefore, the material selection of the electrode terminal 340 can be performed easily.
In addition, since the external terminal member 305 extends away from the exterior body 20, the handling property of the battery 301 can be improved.

  In the fourth embodiment, the external terminal member 305 is a metal piece, but is not limited to this. The external terminal member may be a wire-like member such as a copper wire or a copper wire plated with tin. When the external terminal member is a wire-like member, the cross-sectional shape has no directivity, and is difficult to be cut when handled. In particular, if the external terminal member is a coated wire or a stranded wire in which several wires are bundled, it is difficult to be cut during handling when connecting to an external device.

  Further, in the fourth embodiment, the first ring film 331 does not cover the inner peripheral surface of the through hole 26 of the second container 25, but like the first ring film 31 according to the first embodiment, You may have the cyclic | annular wall part which coat | covers the internal peripheral surface of the through-hole 26. FIG. In this case, the wall portion may be configured to protrude from the through hole 26 in a state before the first ring film is melted so that the wall portion covers the inner peripheral surface of the through hole 26. desirable.

Moreover, in the said 4th Embodiment, although the external terminal member 305 is extended so that it may space apart from the exterior body 20 along an axial direction, it is not limited to this.
FIG. 26 is a perspective view of a battery according to a modification of the fourth embodiment.
For example, as shown in FIG. 26, the external terminal member 306 is formed in a rectangular flat plate shape smaller than the first film through-hole 331a, and is arranged in a face-to-face relationship with the center portion of the electrode terminal 340. The electrode terminal 340 may be electrically connected and fixed. The shape of the external terminal member 306 is not limited to the illustrated shape, and may be a rectangular shape or a circular shape with rounded corners. In particular, it is more preferable to form the external terminal member 306 in a circular shape because the possibility of damaging surrounding members due to the corner portion is reduced.
Even in this configuration, since an external lead wire or the like can be joined to the external terminal member 306, the electrode terminal 340 is formed of a material that is difficult to join, such as aluminum, as in the fourth embodiment. can do. Therefore, the material selection of the electrode terminal 340 can be performed easily.

[Fifth Embodiment]
Next, the first container 421 of the battery according to the fifth embodiment will be described.
FIG. 27 is a cross-sectional view passing through the central axis O of the first container according to the fifth embodiment.
As shown in FIG. 27, the first container 421 of the fifth embodiment is different from the first embodiment shown in FIG. 2 in that it has a first peripheral wall portion 421b formed in a plurality of layers (two layers in the embodiment). Is different.

  The first container 421 is made of a conductive metal material. The first container 421 includes a first bottom wall portion 21a and a first peripheral wall portion 421b. The first peripheral wall portion 421b extends along the axial direction from the outer peripheral edge of the first bottom wall portion 21a, is then folded back toward the outside in the radial direction, and again toward the first bottom wall portion 21a along the axial direction. It extends towards. In other words, the first peripheral wall portion 421b forms a storage space in which the electrode body 10 (see FIG. 2) is stored, and has a cylindrical inner peripheral wall portion 421c facing the electrode body 10, and the inner peripheral wall portion 421c radially outward. A cylindrical outer peripheral wall portion 421d surrounding the entire circumference, and an annular connection portion 421e that connects the inner peripheral wall portion 421c and the outer peripheral wall portion 421d over the entire circumference in the circumferential direction. .

  The dimension in the axial direction of the outer peripheral wall part 421d is equal to the dimension in the axial direction of the inner peripheral wall part 421c. The inner peripheral wall portion 421c and the outer peripheral wall portion 421d are arranged with a gap in the radial direction. The fusion member 29 (see FIG. 2) is heat-sealed to the outer peripheral surface of the outer peripheral wall portion 421d. The connection part 421e is provided at the opening edge of the first container 421. The connecting portion 421e extends from the end edge of the inner peripheral wall portion 421c to the end edge of the outer peripheral wall portion 421d. In the illustrated example, the connecting portion 421e is curved so as to swell toward the opening direction of the first container 421 in the axial direction. The central portion in the radial direction of the connecting portion 421e extends along the radial direction (the thickness direction of the first peripheral wall portion 421b). The first container 421 is formed by drawing, for example.

  As described above, in the present embodiment, the first peripheral wall portion 421b includes the inner peripheral wall portion 421c and the outer peripheral wall portion 421d surrounding the inner peripheral wall portion 421c. Therefore, the first peripheral wall portion is constituted by one peripheral wall portion. Compared with the case where it is done, the intensity | strength of the 1st surrounding wall part 421b can be improved. Thereby, compared with the case where the 1st peripheral wall part is constituted by one peripheral wall part, when fusing member 29 to the 1st peripheral wall part 421b and the 2nd peripheral wall part 25b, the 2nd peripheral wall part 25b. Can be strongly pressed toward the first peripheral wall portion 421b. Therefore, the fusion member 29 can be more reliably fused to the first peripheral wall portion 421b and the second peripheral wall portion 25b, and the airtightness inside the battery can be improved. Further, it is possible to improve work efficiency and yield when the fusion member 29 is fused to the first peripheral wall portion 421b and the second peripheral wall portion 25b.

  Moreover, since the radial direction center part of the connection part 421e is extended along the thickness direction (radial direction) of the 1st surrounding wall part 421b, the external force of the thickness direction acted on the 1st surrounding wall part 421b. At this time, the connecting portion 421e can function like a rib to suppress deformation of the first peripheral wall portion 421b. Therefore, the strength of the first peripheral wall portion 421b against the external force in the thickness direction of the first peripheral wall portion 421b can be improved. Accordingly, when the fusion member 29 is fused to the first peripheral wall portion 421b and the second peripheral wall portion 25b, the second peripheral wall portion 25b can be strongly pressed toward the first peripheral wall portion 421b. Therefore, the fusion | melting member 29 can be more reliably fuse | fused with respect to the 1st surrounding wall part 421b and the 2nd surrounding wall part 25b, and the airtightness inside a battery can be improved. Further, it is possible to improve work efficiency and yield when the fusion member 29 is fused to the first peripheral wall portion 421b and the second peripheral wall portion 25b.

  In the illustrated example, a gap is provided between the inner peripheral wall portion 421c and the outer peripheral wall portion 421d. However, the inner peripheral wall portion 421c and the outer peripheral wall portion 421d may be arranged without a gap. In the present embodiment, the inner peripheral wall portion 421c and the outer peripheral wall portion 421d are integrally formed via the connection portion 421e. However, the inner peripheral wall portion and the outer peripheral wall portion are formed separately and stacked. It may be joined in a state.

The present invention is not limited to the above-described embodiment described with reference to the drawings, and various modifications can be considered within the technical scope thereof.
For example, in the above embodiment, the first container 21 is electrically connected to the negative electrode body 12 and the electrode terminal 40 is electrically connected to the positive electrode body 11, but the present invention is not limited to this. The first container may be electrically connected to the positive electrode body 11 and the electrode terminal may be electrically connected to the negative electrode body 12. In this case, it is preferable to form the first container from aluminum, an aluminum alloy, or the like. The electrode terminals are preferably formed of SUS or the like.

  Moreover, in the said embodiment, although the 1st container 21 is formed with the metal material and the 2nd container 25 is formed with the laminate film, it is not limited to this. For example, the first container may be formed of a laminate film and the second container may be formed of a metal material, or both the first container and the second container may be formed of a metal material or a laminate film.

In the above embodiment, a non-aqueous electrolyte secondary battery has been described as an example of a button-shaped electrochemical cell. However, the present invention is not limited to this case, and the electric double layer capacitor, the primary battery, and the like are described above. The configuration can be applied. In addition, when applying a battery as an electrochemical cell, it is possible to occlude or release expensive cations such as Mg ²⁺ and Al ^{3+ in} addition to monovalent cations such as Li ⁺ and Na ⁺ as active materials for positive and negative electrodes. Materials can be used. When configured as the electric double layer capacitor of the present invention, a high energy density can be realized by using a non-aqueous electrolyte as the electrolyte.

  In addition, it is possible to appropriately replace the constituent elements in the above-described embodiments with well-known constituent elements without departing from the spirit of the present invention, and the above-described embodiments and modifications may be appropriately combined. Good.

  DESCRIPTION OF SYMBOLS 1,101,201,301 ... Battery (electrochemical cell) 5,305,306 ... External terminal member 10,210 ... Electrode body 11, 211 ... Positive electrode body 12, 212 ... Negative electrode body 13,213 ... Positive electrode tab (tab) 14, 214 ... negative electrode tab (tab) 20, 220 ... exterior body 21, 121, 421 ... first container 21b, 121b, 421b ... first peripheral wall part 25 ... second container 25a ... second bottom wall part (second container) 25b ... 2nd surrounding wall part 26 ... Through-hole 29 ... Fusion member 40,140 ... Electrode terminal 41 ... Flange part 145 ... Shaft part 340 ... Electrode terminal (flange part) 421c ... Inner peripheral wall part 421d ... Outer side Peripheral wall part 421e ... Connection part

Claims (10)

An electrode body including a positive electrode body and a negative electrode body;
An exterior body in which the electrode body is accommodated;
With
The exterior body is
A first container formed in a bottomed cylindrical shape and having a first peripheral wall;
A second container formed in a bottomed cylindrical shape, having a second peripheral wall part surrounding the first peripheral wall part, and housing the electrode body between the first container;
A fusion member interposed between the first peripheral wall portion and the second peripheral wall portion, and fused to the first peripheral wall portion and the second peripheral wall portion;
Comprising
An electrochemical cell characterized by that. The first container is formed of a metal material,
The second container is formed of a laminate film containing a metal material and a resin material.
The electrochemical cell according to claim 1. A through hole is formed in the bottom wall of the second container,
In the through hole, an electrode terminal electrically connected to either the positive electrode body or the negative electrode body is inserted,
The electrochemical cell according to claim 2. The inner peripheral surface of the through hole is covered with an insulating material,
The electrochemical cell according to claim 3. The electrode terminal includes a flange portion disposed to face an inner surface of the bottom wall portion of the second container.
The electrochemical cell according to claim 3 or 4, characterized by the above. Outside the exterior body, provided with an external terminal member that conducts with the electrode terminal,
The electrochemical cell according to any one of claims 3 to 5, wherein: The electrode terminal includes a shaft portion extending along the axial direction of the second container in the exterior body,
Either one of the positive electrode body and the negative electrode body is conducted to the shaft portion, and the electrode body is wound.
The electrochemical cell according to any one of claims 3 to 6, wherein the electrochemical cell is characterized in that The first peripheral wall portion is
An inner peripheral wall,
An outer peripheral wall surrounding the inner peripheral wall;
Comprising
The electrochemical cell according to any one of claims 1 to 7, characterized in that The first peripheral wall portion includes a connection portion that connects the inner peripheral wall portion and the outer peripheral wall portion over the entire circumference,
The connection portion extends along the thickness direction of the first peripheral wall portion,
The electrochemical cell according to claim 8. The electrode body is formed by laminating the positive electrode body and the negative electrode body,
The electrode body has a tab protruding in a direction intersecting the stacking direction with respect to the stacked portion of the positive electrode body and the negative electrode body,
The electrochemical cell according to any one of claims 1 to 9, wherein the electrochemical cell is characterized.

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