JP2021170493A - Electrochemical cell and electronic equipment - Google Patents

Abstract

To enhance a degree of freedom in shape of an electrode body and thus to improve a volumetric efficiency.SOLUTION: An electrochemical cell 10 comprises: an electrode body 11; and an outer package 13 formed by a laminate film 12 and accommodating the electrode body therein. The outer package comprises: a housing part 50 for housing the electrode body therein; and an encapsulation part 51 where certain parts of the laminate film are bonded while being overlapped with each other to encapsulate the inside of the housing part. The electrode body at least comprises: a first extending part 11a that extends in a first direction L1 in a plan view seen from a battery axis O-direction; and a second extending part 11b that extends in a second direction L2 crossing the first direction. The housing part comprises: a top wall 55 and a bottom wall opposed to each other in the battery axis direction while interposing the electrode body therebetween; and a peripheral wall 57 folded along an outer shape of the electrode body and surrounding the electrode body from the outside over the whole periphery. The encapsulation part is formed to be folded along the outer shape of the electrode body and to further surround the peripheral wall from the outside.SELECTED DRAWING: Figure 2

Description

The present invention relates to electrochemical cells and electronic devices.

Conventionally, electrochemical cells such as lithium ion secondary batteries and electrochemical capacitors have been widely used as a power source for small devices such as smartphones, wearable devices, and hearing aids. In this type of electrochemical cell, as an exterior body for accommodating an electrode body inside, for example, a metal case is known as shown in Patent Document 1 below.
Specifically, the exterior body is provided with a bottomed cylindrical case body and a sealing case that seals the opening of the case body by crimping or the like via a gasket, and has a coin shape, a button shape, etc. as a whole. It is formed.

However, in recent years, so-called laminate-type electrochemical cells (see, for example, Patent Document 2), which form an exterior body using a laminate film in order to improve the degree of freedom in shape, are suitable for various electronic devices. It is beginning to be used.

International Publication No. 02/13305 JP-A-2002-141030

In general, a laminated type electrochemical cell has a structure in which a laminated film is heat-welded in a state where an electrode body having a positive electrode, a negative electrode, and a separator is housed inside together with an electrolytic solution or the like to seal and seal the inside. It is said that. Therefore, the portion of the laminated film that internally accommodates the electrode body and the electrolytic solution functions as an accommodating portion, and the portion that is heat-welded so as to surround the accommodating portion functions as a welded portion. That is, the exterior body formed by the laminated film is mainly composed of the accommodating portion and the welding portion.

By the way, in order to maintain the airtightness in the accommodating portion, it is necessary to form the welded portion with a sufficient welding width (welding allowance). However, since the welded portion is a portion that is not related to the accommodation of the electrode body, it is a factor that lowers the volumetric efficiency. The volumetric efficiency refers to the ratio of the volume occupied by the electrode body to the total volume of the electrochemical cell, that is, "partial volume of the electrode / total volume of the battery".

In particular, laminated-type electrochemical cells have traditionally been formed in a so-called square shape such as a rectangular shape in a plan view, but in recent years, it is known that the outer shape is formed in a shape other than the square shape. Has been done.
The reason is that, for example, in a small portable electronic device such as a smartphone, it is often required to install a specific functional module such as a camera mechanism at a predetermined position in the housing. Therefore, the remaining empty space in the housing is limited, and the space shape of the empty space itself is likely to be restricted. Under such circumstances, when the electrochemical cell is square, it is difficult to make sufficient effective use of the empty space. For this reason, it is required to form the electrochemical cell in an outer shape other than the square shape in response to the empty space.

The electrochemical cells formed in an outer shape other than the square shape as described above can become mainstream in the future as electronic devices are further miniaturized, thinned, and multifunctional, and the volumetric efficiency is improved. It is required to let.

The present invention has been made in consideration of such circumstances, and an object of the present invention is to provide a laminate-type electrochemical cell and an electronic device having a high degree of freedom in the shape of an electrode body and capable of improving volumetric efficiency. To provide.

(1) The electrochemical cell according to the present invention is formed of an electrode body having a positive electrode and a negative electrode, and a laminated film having a metal layer and a resin layer covering both surfaces of the metal layer, and the electrode body is inside. The exterior body is provided with an exterior body for accommodating the electrode body, and the accommodating portion for accommodating the electrode body and the laminated films are joined to each other in a state of being overlapped with each other to seal the inside of the accommodating portion. The electrode body includes a portion, and the electrode body extends in a first extending portion extending in the first direction and extending in a second direction intersecting the first direction and the first extending portion in a plan view from the battery axis direction. The accommodating portion is provided with at least a second extending portion connected to the electrode body, and the accommodating portion follows the outer shape of the electrode body with the top wall portion and the bottom wall portion facing the battery axis direction with the electrode body interposed therebetween. It is provided with a peripheral wall portion that surrounds the electrode body from the outside over the entire circumference, and the sealing portion is bent according to the outer shape of the electrode body, and the peripheral wall portion is further bent from the outside. It is characterized in that it is formed so as to surround it.

According to the electrochemical cell according to the present invention, since the exterior body is formed by using a laminated film having a metal layer and a resin layer, the sealing portion is formed by joining the laminated films to each other by, for example, heat welding. It can be configured with high sealing property (adhesion). In addition, since the sealing portion is bent, it is possible to effectively prevent disturbances such as dust and moisture from entering the accommodating portion from the outside through between the laminated films. Therefore, it is possible to obtain an electrochemical cell with stable operation reliability. Further, since the exterior body is formed by using a thin laminated film, the thickness of the peripheral wall portion and the sealing portion itself can be reduced. Therefore, it is easy to reduce the diameter of the electrochemical cell.

In particular, since the electrode body is configured to include at least a first extension portion and a second extension portion that intersect each other, for example, an L-shape, a T-shape, or an E-shape in a plan view from the battery axis direction. It can be an outer shape such as a character shape. Therefore, it is possible to form an outer shape other than the square shape (rectangular shape in a plan view, etc.) that has been generally formed in the past, and for example, the outer shape can be made to correspond to the space where the installation is planned. .. Therefore, the degree of freedom in the shape of the electrode body can be increased, and an easy-to-use electrochemical cell that can flexibly meet the demands of various electronic devices can be obtained.
Moreover, since the sealing portion where the laminated films are joined is bent according to the outer shape of the electrode body, the size of the entire electrochemical cell can be reduced without changing the size of the accommodating portion for accommodating the electrode body. Can be done. Therefore, the volume ratio occupied by the electrode body to the volume of the entire vapor chemistry cell can be improved, and the volume efficiency can be improved.

(2) The sealing portion may be formed so as to surround the peripheral wall portion from the outside over the entire circumference.

In this case, for example, at the time of manufacturing, two laminated films are laminated in the battery axis direction with an electrode body in between, and then the two laminated films are joined to each other by heat welding or the like to form a sealing portion. can do. Then, by bending the sealing portion according to the outer shape of the electrode body with a molding die or the like, the sealing portion can be formed so as to surround the peripheral wall portion from the outside over the entire circumference. As described above, since the exterior body can be formed by using the two laminated films, it is easy to improve the manufacturing efficiency of the electrochemical cell.

(3) The sealing portion may come into contact with the peripheral wall portion from the outside.

In this case, since the sealing portion is brought into contact with the peripheral wall portion from the outside, the sealing portion can be arranged on the outside of the peripheral wall portion without leaving a gap between the sealing portion and the peripheral wall portion. Therefore, since the gap can be omitted, the diameter of the entire electrochemical cell can be further reduced, which can lead to further improvement in volumetric efficiency.

(4) The top wall portion or the bottom wall portion is provided with a positive electrode plate that is electrically connected to the positive electrode and is exposed to the outside, and is electrically connected to the negative electrode. A negative electrode plate exposed to the outside may be provided at the same time.

In this case, since the positive electrode plate and the negative electrode plate can function as external connection terminals, it is not necessary to provide external connection terminals so as to project outward from the sealing portion, for example. As a result, it is possible to further reduce the size of the electrochemical cell, and it is easy to improve the assembling property when, for example, the electrochemical cell is assembled in an electronic device.

(5) The electronic device according to the present invention includes the electrochemical cell, a housing case for accommodating the electrochemical cell inside, and a functional module arranged in the housing case. Is arranged by utilizing the space defined between the first extension portion and the second extension portion that intersect each other.

According to the electronic device according to the present invention, since the functional module can be arranged by using the space defined between the first extension portion and the second extension portion, the function module can be efficiently functioned in the housing case. In addition to being able to arrange modules and electrochemical cells, it is possible to secure a large proportion of the electrochemical cells in the limited installation space inside the housing case. Therefore, it is possible to obtain an electronic device with improved battery performance without changing the size of the entire electronic device.

According to the present invention, it is possible to obtain a laminate-type electrochemical cell and an electronic device having a high degree of freedom in the shape of the electrode body and capable of improving volumetric efficiency.

It is a top view which shows the embodiment of the portable information terminal (electronic device) which concerns on this invention. It is a perspective view of the secondary battery (electrochemical cell) shown in FIG. It is a vertical sectional view of the secondary battery along the line AA shown in FIG. It is a vertical sectional view of the secondary battery which enlarged the part surrounded by the virtual circle B shown in FIG. FIG. 3 is an enlarged partial cross-sectional view of the electrode body shown in FIG. It is a figure which shows one step in the manufacturing process of the secondary battery shown in FIG. 2, and is the perspective view of the premolded battery which was housed so as to wrap the electrode body by using one laminated film. It is a perspective view of the molding die. FIG. 5 is a perspective view showing a state in which the pre-molding battery shown in FIG. 6 is set in the first mold and the punch portion after the punch portion is inserted into the inside of the first mold shown in FIG. 7. FIG. 8 is a cross-sectional view showing a state in which the sealing portion of the premolding battery is sandwiched and fixed between the first mold and the second mold after the state shown in FIG. 8, and is a cross-sectional view taken along the line CC shown in FIG. It is a cross-sectional view along. It is sectional drawing which shows the state which starts to raise a punch part after the state shown in FIG. FIG. 10 is a cross-sectional view showing a state in which the sealing portion is bent and molded by using the molded portion of the punch portion after the state shown in FIG. FIG. 11 is a cross-sectional view showing a state in which the post-molding battery in which the sealing portion is bent and molded is taken out from the molding die after the state shown in FIG. It is sectional drawing which shows the state which set the battery after molding in the die for drawing molding after the state shown in FIG. FIG. 3 is a cross-sectional view showing a state in which the sealing portion of the battery is drawn and molded after the state shown in FIG. It is a perspective view which shows the modification of the secondary battery which concerns on this invention. It is a perspective view which shows another modification of the secondary battery which concerns on this invention. It is a perspective view which shows the further modification of the secondary battery which concerns on this invention. It is a perspective view of the molding die used in manufacturing the secondary battery shown in FIG.

Hereinafter, embodiments of the electrochemical cell and electronic device according to the present invention will be described with reference to the drawings.
In the present embodiment, as the electrochemical cell, a lithium ion secondary battery (hereinafter, simply referred to as a secondary battery), which is a kind of non-aqueous electrolyte secondary battery, will be described as an example. Further, as an electronic device, a mobile information terminal such as a smartphone will be described as an example.

(Mobile information terminal)
As shown in FIG. 1, the portable information terminal 1 of the present embodiment includes a casing (housing case according to the present invention) 2 having a touch panel (not shown) operated by a fingertip.
Note that FIG. 1 is a plan view of the casing 2 as viewed from the back surface side. Further, in the present embodiment, the two directions orthogonal to each other in the thickness direction of the casing 2 in the plan view of the casing 2 are referred to as the first direction L1 and the second direction L2.

The casing 2 is formed in a rectangular shape in a plan view in which the length along the first direction L1 is longer than the length along the second direction L2, and is formed in a thin bottomed cylinder shape. A cover glass (not shown) is integrally combined on the front side of the casing 2 to seal the inside of the casing 2.
Inside the casing 2, a plurality of control boards including a main board and a sub board 3 (not shown) are incorporated. For example, on the main board, a CPU that comprehensively controls the mobile information terminal 1 and a plurality of electronic components for executing various operations are mounted. A touch panel (not shown) and a liquid crystal display panel such as an LCD (Liquid Crystal Display) are arranged so as to overlap between the main substrate and the cover glass. This makes it possible to operate the touch panel with a fingertip through the cover glass in response to various information displayed on the liquid crystal display panel.

Further, inside the casing 2, a plurality of functional modules that exert various functions as the portable information terminal 1 are mounted, and a secondary battery 10 is housed in the casing 2. One of the functional modules is, for example, a back camera module 4 arranged on the back surface side of the casing 2.
The back camera module 4 mainly includes a camera substrate 5 and a camera unit 6 arranged so as to be exposed to the outside through a camera window 2a formed on the back surface side of the casing 2.

The back camera module 4 is mainly arranged at the corner of the casing 2 in consideration of the usage mode as the portable information terminal 1. In the illustrated example, the camera unit 6 is a so-called twin-lens camera (dual camera) in which two camera units 6 are arranged so as to be arranged along the first direction L1. However, the number of camera units 6 may be one, or three or more may be provided.

The secondary battery 10 is formed in an L-shape in a plan view, and the occupied area is secured as much as possible inside the casing 2 while avoiding interference with the back camera module 4 and other components. Have been placed.
Hereinafter, the secondary battery 10 will be described in detail.

(Secondary battery)
As shown in FIGS. 2 to 5, the secondary battery 10 of the present embodiment includes a plurality of electrodes stacked on each other along the battery axis O direction, that is, an electrode body 11 having a positive electrode 20 and a negative electrode 30. It is formed of a laminated film 12, and mainly includes an exterior body 13 that houses the electrode body 11 inside. In each drawing, the electrode body 11 is shown in a simplified manner as appropriate.

In the present embodiment, the battery shaft O direction is the thickness direction of the casing 2. Therefore, the secondary battery 10 is configured such that the positive electrode 20 and the negative electrode 30 are laminated in the thickness direction of the casing 2. Further, in explaining the configuration of the secondary battery 10, the direction from the front surface side to the back surface side of the casing 2 along the battery shaft O is referred to as an upward direction, and the opposite direction is referred to as a downward direction.

As shown in FIG. 5, the electrode body 11 is a so-called laminated electrode in which the positive electrode 20 and the negative electrode 30 are laminated in the battery axis O direction with the separator 40 interposed therebetween. However, the present invention is not limited to this case, and a so-called pellet type electrode body may be provided in which the positive electrode 20 and the negative electrode 30 are provided on both sides of the separator 40. In drawings other than FIG. 5, the positive electrode 20 and the negative electrode 30 are not shown with the separator 40.

As shown in FIG. 2, the electrode body 11 is orthogonal to the first extending portion 11a extending along the first direction L1 and the first direction L1 in a plan view from the battery axis O direction. It extends along the intersecting second direction L2 and includes a second extension portion 11b that is connected to the first extension portion 11a and is formed in an L-shape in a plan view.
In the second direction L2, the direction in which the second extension portion 11b extends from the first extension portion 11a is referred to as the front, and the opposite side is referred to as the rear.

Therefore, the first extension portion 11a extends along the longitudinal direction of the casing 2, and the second extension portion 11b extends along the lateral direction (width direction) of the casing 2 (see FIG. 1). Further, the electrode body 11 is formed so that the length along the first direction L1 is longer than the length along the second direction L2, corresponding to the outer shape of the casing 2. Therefore, of the side wall surfaces of the electrode body 11, the rear wall surface 11c facing the rear side corresponds to the longest side wall surface.

The electrode body 11 is formed so that the length of the first extension portion 11a along the second direction L2 and the length of the second extension portion 11b along the first direction L1 are different. The length is not limited to the case, and may be formed so as to have the same length.

As described above, since the electrode body 11 is externally formed in an L-shape in a plan view, the positive electrode 20, the negative electrode 30 and the separator 40 constituting the electrode body 11 are also formed in an L-shape in a plan view, respectively. ing.
However, the positive electrode 20 is formed so as to have an outer size smaller than that of the negative electrode 30. Further, the separator 40 is formed so as to have an outer size larger than that of, for example, the positive electrode 20 from the viewpoint of preventing a short circuit or the like. The separator 40 may be formed in the shape of a sheet having an L-shape in a plan view, or may be formed in a bag shape in an L-shape in a plan view in which the positive electrode 20 is confined inside.

As shown in FIG. 5, the positive electrode electrode 20 is formed on both sides of a positive electrode current collector (positive electrode current collector foil) 21 formed of a metal material such as aluminum or stainless steel in a thin sheet shape and a positive electrode current collector 21. It is formed in the form of a single sheet provided with a positive electrode active material layer 22 formed by coating or the like. The positive electrode current collector 21 is formed into an L-shape in a plan view by, for example, punching. The positive electrode active material layer 22 contains a positive electrode active material, a conductive auxiliary agent, a binder, a thickener, and the like, and is formed of, for example, a composite metal oxide such as lithium cobalt oxide and lithium nickel oxide.

Examples of the conductive auxiliary agent include carbon blacks, carbon materials, metal fine powders and the like. Examples of the binder include resin materials such as polyvinylidene fluoride (PVDF), styrene butadiene rubber (SBR) and polytetrafluoroethylene (PTFE). Examples of the thickener include a resin material such as carboxymethyl cellulose (CMC).

The negative electrode electrode 30 is formed by coating on both sides of a negative electrode current collector (negative electrode current collector foil) 31 formed of a thin sheet of metal material such as copper, nickel, and stainless steel, and the negative electrode current collector 31. It is formed in the form of a single sheet including the formed negative electrode active material layer 32. The negative electrode current collector 31 is formed into an L-shape in a plan view by, for example, punching. The negative electrode active material layer 32 contains a negative electrode active material, a conductive auxiliary agent, a binder, a thickener, and the like, and is formed of a carbon material such as graphite.

Examples of the conductive auxiliary agent include carbon blacks, carbon materials, metal fine powders and the like. Examples of the binder include resin materials such as polyvinylidene fluoride (PVDF), styrene butadiene rubber (SBR) and polytetrafluoroethylene (PTFE). Examples of the thickener include a resin material such as carboxymethyl cellulose (CMC).

The separator 40 is formed of, for example, a resin porous film made of polyolefin, a non-woven fabric made of glass, a non-woven fabric made of resin, a laminate of cellulose fibers, or the like, and allows lithium ions to pass through ion permeation holes (not shown). The separator 40 is formed in an L-shape in a plan view, and when formed in a sheet shape as described above, the separator 40 is arranged in the entire interlayer layer between the positive electrode 20 and the negative electrode 30, so that the positive electrode 20 is formed. Is insulated from the negative electrode 30 and the negative electrode 30.

The electrode body 11 is configured such that the positive electrode 20 and the negative electrode 30 configured as described above are alternately laminated in the battery axis O direction with the separator 40 sandwiched between them. At this time, the electrode body 11 is configured so that the positive electrode 20 is located at the top and the negative electrode 30 is located at the bottom.

The positive electrode current collector 21 of each positive electrode 20 stacked in the battery shaft O direction is, for example, an extension portion (not shown) extending in a band shape so that a part thereof protrudes to the outside of the electrode body 11. Each of the extending portions of each of these positive electrode electrodes 20 is bundled into one. A positive electrode terminal tab 23 made of aluminum or the like is connected to the extending portion bundled into one.
As shown in FIG. 3, the positive electrode terminal tab 23 is arranged so as to be located above the positive electrode electrode 20 located at the uppermost stage, for example, by being folded back at a connecting portion with the extending portion. The positive electrode active material layer 22 is not formed on the positive electrode terminal tab 23.

Similarly, the negative electrode current collector 31 of each negative electrode 30 stacked in the battery axis O direction is, for example, an extension portion (not shown) extending in a band shape so that a part thereof protrudes to the outside of the electrode body 11. .. Each of the extending portions of each of these negative electrode electrodes 30 is bundled into one. A negative electrode terminal tab 33 made of nickel or the like is connected to the extending portion bundled into one.
As shown in FIG. 3, the negative electrode terminal tab 33 is arranged so as to be located above the positive electrode 20 located at the uppermost stage, for example, by being folded back at a connecting portion with the extending portion.
Therefore, in the present embodiment, the positive electrode terminal tab 23 and the negative electrode terminal tab 33 are arranged on the upper surface side of the electrode body 11.

Specifically, as shown in FIG. 2, the positive electrode terminal tab 23 and the negative electrode terminal tab 33 are arranged so as to be arranged at intervals in the first direction L1 on the upper surface of the second extending portion 11b on the front end side. Has been done. However, the positions of the positive electrode terminal tab 23 and the negative electrode terminal tab 33 are not limited to this case, and may be appropriately changed, for example, by arranging them on the upper surface side of the first extension portion 11a.

The exterior body 13 is formed by using one laminated film 12.
As shown in FIG. 4, the laminated film 12 has a metal layer 12a, an inner resin layer 12b and an outer resin layer 12c that cover both sides of the metal layer 12a. The inner resin layer 12b and the outer resin layer 12c are closely bonded to both surfaces of the metal layer 12a via a bonding layer (not shown), for example, by heat fusion or adhesion.
In each drawing other than FIG. 4, the metal layer 12a, the inner resin layer 12b, and the outer resin layer 12c are not shown as appropriate.

The metal layer 12a is made of a metal material suitable for blocking outside air and water vapor, such as stainless steel and aluminum.
The inner resin layer 12b is formed by using a thermoplastic resin such as polyolefin polyethylene or polypropylene. Examples of the polyolefin include high-pressure low-density polyethylene (LDPE), low-pressure high-density polyethylene (HDPE), inflation polypropylene (IPP) film, unstretched polypropylene (CPP) film, biaxially stretched polypropylene (OPP) film, and linear chain. Any material of short-chain branched polyethylene (L-LDPE, metallocene catalyst specification) can be used. In particular, a propylene propylene resin is preferable.
The outer resin layer 12c is formed by using, for example, the above-mentioned polyolefin, polyester such as polyethylene terephthalate, nylon, or the like.

As shown in FIGS. 2 to 4, the exterior body 13 is joined to each other in a state where the accommodating portion 50 accommodating the electrode body 11 and the laminated films 12 are overlapped with each other to seal the inside of the accommodating portion 50. It is provided with a sealing portion 51. As a result, the exterior body 13 accommodates the above-mentioned electrode body 11 in a sealed state inside the accommodating portion 50. Further, the inside of the accommodating portion 50 is filled with an electrolyte solution (electrolyte solution) (not shown).

The accommodating portion 50 is bent according to the outer shape of the electrode body 11 with the top wall portion 55 and the bottom wall portion 56 facing the battery axis O direction with the electrode body 11 sandwiched therein, and the electrode body 11 is stretched over the entire circumference. It is provided with a peripheral wall portion 57 that surrounds the battery from the outside.

The sealing portion 51 is bent from the bottom wall portion 56 side toward the top wall portion 55 side (upward) according to the outer shape of the electrode body 11, and further surrounds the peripheral wall portion 57 from the outside of the battery. Moreover, it is in contact with the peripheral wall portion 57 from the outside of the battery.

In the present embodiment, the sealing portion 51 does not form the peripheral wall portion 57 over the entire circumference, but surrounds the peripheral wall portion 57 from the outside of the battery except for a part of the peripheral wall portion 57. Specifically, the sealing portion 51 surrounds the peripheral wall portion 57 from the outside of the battery except for the rear wall portion 57a located on the rear side. The rear wall portion 57a surrounds the rear wall surface 11c of the electrode body 11 from the outside of the battery (see FIG. 2).

The exterior body 13 including the accommodating portion 50 and the sealing portion 51 will be described in detail below.
As described above, the exterior body 13 is formed by using one laminated film 12. Specifically, one laminated film 12 wraps the electrode body 11 from above and below by being folded so as to be folded 180 degrees along the rear wall surface 11c. Then, the laminated films 12 that are doubly laminated in the vertical direction on the outside of the electrode body 11 are joined by heat welding or the like to form a sealing portion 51, and the sealing portion 51 is bent further upward. The exterior body 13 is formed. This will be described again later.

In the present embodiment, the portion of one laminated film 12 that mainly covers the electrode body 11 from above is referred to as an upper laminate film 12A, and the portion that mainly covers the electrode body 11 from below is referred to as a lower laminate film 12B. ..

The upper laminated film 12A has an L-shaped top wall portion 60 in a plan view that covers the electrode body 11 from above, and a peripheral wall portion that extends downward from the outer peripheral edge portion of the top wall portion 60 and surrounds the electrode body 11 from the outside of the battery. It is provided with 61 and a first sealing portion 62 that is folded upward from the lower end portion of the peripheral wall portion 61 and surrounds a portion excluding the rear wall portion 57a from the outside of the battery.

The lower laminated film 12B extends upward from the bottom wall portion 65 having an L-shape in a plan view covering the electrode body 11 from below and the outer peripheral edge portion of the bottom wall portion 65, and the first sealing portion 62 is a battery. It is provided with a second sealing portion 66 that further surrounds from the outside.

Then, the top wall portion 60 and the peripheral wall portion 61 in the upper laminated film 12A function as the top wall portion 55 and the peripheral wall portion 57 as the accommodating portion 50, respectively. Further, the bottom wall portion 65 of the lower laminated film 12B functions as the bottom wall portion 56 as the accommodating portion 50. Further, the first sealing portion 62 in the upper laminated film 12A and the second sealing portion 66 in the lower laminated film 12B function as the sealing portion 51.

The first sealing portion 62 and the second sealing portion 66 that function as the sealing portion 51 are integrally joined to each other, thereby sealing the inside of the accommodating portion 50 in a sealed state.
Specifically, the inner resin layer 12b in the first sealing portion 62 and the inner resin layer 12b in the second sealing portion 66 are integrally joined by, for example, ultrasonic welding or heat welding. However, the joining method is not limited to ultrasonic welding or heat welding, and for example, high-frequency welding or bonding using an adhesive may be used.

In the present embodiment, the height position of the upper end portion of the sealing portion 51 is the same as the height position of the top wall portion 55 in the accommodating portion 50. As a result, the sealing portion 51 is formed without protruding upward from the top wall portion 55.
However, the present invention is not limited to this case, and for example, the height position of the upper end portion of the sealing portion 51 may be formed so as to be located above or below the top wall portion 55.

In particular, the first sealing portion 62 and the second sealing portion 66 are integrally joined to each other and then bent and molded by the molding die 80 described later, and subsequently reduced in diameter by the drawing die 90 described later. It is formed by drawing and molding so as to do so.
As a result, the sealing portion 51 composed of the first sealing portion 62 and the second sealing portion 66 is in close contact with the outer peripheral surface of the peripheral wall portion 57 in a close contact state pressed from the outside of the battery. ..

Further, as shown in FIGS. 2 and 3, the secondary battery 10 of the present embodiment includes a first electrode plate 70 and a second electrode plate 71, a first electrode terminal plate 72 and a second electrode terminal plate 73, and a second electrode plate 73. It includes one sealant film 74 and a second sealant film 75.
The first electrode plate 70, the second electrode plate 71, the first electrode terminal plate 72, the second electrode terminal plate 73, the first sealant film 74, and the second sealant film 75 are inside the accommodating portion 50 in the exterior body 13. It is housed together with the electrode body 11. Specifically, the first electrode plate 70, the second electrode plate 71, the first electrode terminal plate 72, the second electrode terminal plate 73, the first sealant film 74, and the second sealant film 75 are laminated with the electrode body 11 on the upper side. It is arranged between the film 12A and the top wall portion 60.

The first electrode plate 70 is formed of, for example, a square in a plan view by a metal material such as aluminum or stainless steel, and a positive electrode terminal tab 23 is welded on the lower surface side by, for example, ultrasonic welding. As a result, the first electrode plate 70 is integrally connected to the positive electrode 20.
The first electrode terminal plate (positive electrode plate according to the present invention) 72 is formed of a metal material such as nickel in a square shape in a plan view smaller than that of the first electrode plate 70, and overlaps the upper surface of the first electrode plate 70. Have been placed. The first electrode terminal plate 72 is integrally fixed to the upper surface of the first electrode plate 70 by, for example, welding by resistance welding or the like. As a result, the first electrode terminal plate 72 functions as an external connection terminal of the positive electrode 20.

The top wall portion 60 of the upper laminated film 12A is formed with a first through hole 76 having a square shape in a plan view for exposing the first electrode terminal plate 72 to the outside. The first through hole 76 is formed so as to vertically penetrate the top wall portion 60.
The first sealant film 74 is formed in an annular shape surrounding the first electrode terminal plate 72, and is between the first electrode terminal plate 72 and the top wall portion 60 of the upper laminated film 12A in a state of surrounding the first electrode terminal plate 72. It is located in. The first sealant film 74 is heat-welded to the inner resin layer 12b of the top wall portion 60 and the upper surface of the first electrode plate 70, respectively. As a result, the first electrode plate 70 is heat-welded to the top wall portion 60 via the first sealant film 74.
The first sealant film 74 is made of a thermoplastic resin such as polyethylene or polypropylene of poreolefin or polypropylene reinforced with a non-woven fabric.

Since the first electrode plate 70, the first electrode terminal plate 72, and the first sealant film 74 are formed as described above, the entire surface of the first electrode terminal plate 72 is exposed upward through the first through hole 76. ..

The second electrode plate 71, the second electrode terminal plate 73, and the second sealant film 75 are formed and arranged in the same manner as the first electrode plate 70, the first electrode terminal plate 72, and the first sealant film 74 described above. ing.

The second electrode plate 71 is formed of, for example, a metal material such as copper into a square in a plan view, and the negative electrode terminal tab 33 is welded to the lower surface side by, for example, ultrasonic welding. As a result, the second electrode plate 71 is integrally connected to the negative electrode electrode 30.
The second electrode terminal plate (negative electrode plate according to the present invention) 73 is formed of a metal material such as nickel in a square shape in a plan view smaller than that of the second electrode plate 71, and overlaps the upper surface of the second electrode plate 71. Have been placed. The second electrode terminal plate 73 is integrally fixed to the upper surface of the second electrode plate 71 by, for example, welding by resistance welding or the like. As a result, the second electrode terminal plate 73 functions as an external connection terminal for the negative electrode.

The top wall portion 60 of the upper laminated film 12A is formed with a second through hole 77 having a square shape in a plan view that exposes the second electrode terminal plate 73 to the outside. The second through hole 77 is formed so as to penetrate the top wall portion 60 vertically, and is arranged at intervals in the first direction L1 with respect to the first through hole 76.
The second sealant film 75 is formed in an annular shape surrounding the second electrode terminal plate 73, and is between the second electrode terminal plate 73 and the top wall portion 60 of the upper laminated film 12A in a state of surrounding the second electrode terminal plate 73. It is located in. The second sealant film 75 is heat-welded to the inner resin layer 12b of the top wall portion 60 and the upper surface of the second electrode plate 71, respectively. As a result, the second electrode plate 71 is heat-welded to the top wall portion 60 via the second sealant film 75.
Like the first sealant film 74, the second sealant film 75 is made of a thermoplastic resin such as polyethylene or polypropylene of poreolefin, or polypropylene reinforced with a non-woven fabric.

Since the second electrode plate 71, the second electrode terminal plate 73, and the second sealant film 75 are formed as described above, the entire surface of the second electrode terminal plate 73 is exposed upward through the second through hole 77. ..

The shapes of the first electrode terminal plate 72 and the second electrode terminal plate 73 are not limited to a square shape in a plan view, and may be appropriately changed, for example, a circular shape in a plan view, an elliptical shape, a rectangular shape, or the like. .. Further, it is not necessary for the first electrode terminal plate 72 and the second electrode terminal plate 73 to have the same outer size, and the first electrode terminal plate 72 and the second electrode terminal plate 73 may be formed so as to have different sizes.

(Manufacturing method of secondary battery)
Next, a method of bending and drawing the sealing portion 51 in manufacturing the secondary battery 10 configured as described above will be described.
First, as shown in FIG. 6, one laminated film 12 is folded so as to be folded back 180 degrees along the rear wall surface 11c of the electrode body 11, so that the electrode body 11 is housed inside so as to be wrapped from the vertical direction. As a result, the upper laminated film 12A and the lower laminated film 12B are doubly overlapped on the outside of the electrode body 11.
Then, with the electrolyte solution filled inside, the portions of the upper laminated film 12A and the lower laminated film 12B that are doubly overlapped, that is, the first sealing portion 62 and the second sealing portion 66 are ultrasonically charged. A step of integrally joining by welding or the like is performed.

As a result, the first sealing portion 62 and the second sealing portion 66 are integrally joined, so that the premolding battery 10A including the accommodating portion 50 and the sealing portion 51 can be obtained.
At this stage, the entire surface of the first electrode terminal plate 72 and the second electrode terminal plate 73 is exposed upward through the first through hole 76 and the second through hole 77, respectively.

Next, a step of bending and molding the sealing portion 51 is performed using the molding die 80 shown in FIG. 7.
The molding mold 80 is arranged above the first mold 81 that supports the pre-molding battery 10A and the first mold 81, and can be approached and separated from the first mold 81 in the battery shaft O direction. The second die 82 is provided, and the punch portion 83 is arranged so as to be relatively movable in the battery shaft O direction with respect to the first die 81 and the second die 82.

The first mold 81 is formed with a first molding hole 84 that penetrates the first mold 81 in the battery shaft O direction. The first forming hole 84 is formed in an L-shape in a plan view corresponding to the shape of the electrode body 11. The upper surface of the first mold 81 is a mounting surface 81a on which the sealing portion 51 is supported.
The second mold 82 is formed with a second molding hole 85 that penetrates the second mold 82 in the battery shaft O direction. The second forming hole 85 is formed in a plan view L-shape having the same size as the first forming hole 84, and faces the first forming hole 84 in the battery axis O direction. The lower surface of the second mold 82 is a pressing surface 82a capable of pressing the sealing portion 51 from above with the mounting surface 81a.

The punch portion 83 is arranged below the first mold 81 and rises with respect to the first mold 81 and the second mold 82, so that the inside of the first forming hole 84 and the second forming hole 85 are formed. It is possible to enter inside from below.
The punch portion 83 has a punch portion main body 86 formed in an L shape in a plan view smaller than the opening sizes of the first forming hole 84 and the second forming hole 85, and the punch portion 83 projects upward from the upper surface of the punch portion main body 86. A molded portion 87 formed as described above is provided. The molded portion 87 is formed along a portion of the peripheral wall portion 57 of the exterior body 13 excluding the rear wall portion 57a. Further, the protruding length of the molded portion 87 (the length along the battery shaft O direction) is the same as the height of the accommodating portion 50.

When the sealing portion 51 is bent and molded by using the molding die 80 configured as described above, for example, the punch portion 83 shown in FIG. 7 is moved upward from below the first mold 81. Then, the punch portion 83 is made to stand by in the first forming hole 84. At this time, the punch portion 83 is made to stand by so that the height position of the upper end portion of the molding portion 87 is flush with the mounting surface 81a of the first mold 81.

Next, as shown in FIG. 8, the pre-molding battery 10A is placed on the first mold 81 and the punch portion 83 with the first electrode terminal plate 72 and the second electrode terminal plate 73 facing the punch portion 83 side. Place it. As a result, the accommodating portion 50 is arranged in the first forming hole 84, and the sealing portion 51 located outside the accommodating portion 50 is placed on the mounting surface 81a. Further, the accommodating portion 50 is supported on the punch portion main body 86 in a state of being inserted inside the molding portion 87 of the punch portion 83. Further, the molded portion 87 can be brought into contact with the sealing portion 51 from below. As a result, it is possible to stably support the pre-molded battery 10A.
In FIG. 8, the punch portion 83 that has entered the first forming hole 84 is not shown in order to make the drawing easier to see.

However, the process is not limited to the above-mentioned process, and the premolding battery 10A may be placed on the first mold 81 at a stage before the punch portion 83 is inserted into the first molding hole 84, for example.

Next, as shown in FIG. 9, the second mold 82 is moved closer to the first mold 81 from above, and the second mold 82 is overlapped with the first mold 81 in the battery shaft O direction. match. As a result, the sealing portion 51 can be sandwiched and fixed between the mounting surface 81a of the first mold 81 and the pressing surface 82a of the second mold 82.

Next, as shown in FIG. 10, the punch portion 83 is moved upward. As a result, as shown in FIG. 11, the sealing portion 51 can be lifted by using the molding portion 87, and the inner surface of the second molding hole 85 and the outer surface of the molding portion 87 are used to form an L-shape in a plan view. The sealing portion 51 can be bent and molded according to the outer shape of the electrode body 11 having a shape.

Further, by moving the upper end edge of the punch portion main body 86 above the lower end edge of the second forming hole 85, the sealing portion 51 can be cut between the upper end edge and the lower end edge, and the sealing portion 51 can be sealed. The portion of the portion 51 sandwiched between the mounting surface 81a and the pressing surface 82a can be separated.

As a result, as shown in FIG. 12, the post-molded battery 10B in which the sealing portion 51 is bent so as to surround the accommodating portion 50 can be obtained. As a result, the sealing portion 51 is bent and molded so as to surround the portion of the peripheral wall portion 57 excluding the rear wall portion 57a from the outside of the battery. However, in the molded battery 10B, since the sealing portion 51 is bent and molded by using the molding portion 87 of the punch portion 83, a gap portion S is drawn between the accommodating portion 50 and the sealing portion 51. It is made.

Next, using the draw molding die 90 shown in FIG. 13, the sealing portion 51 is drawn and molded inward to fill the gap S described above.
The drawing die 90 includes a first drawing die 91, a second drawing die 92 that can move relative to the first drawing die 91 in the battery axis O direction, and a second drawing die 92. After molding, the battery 10B is sandwiched and fixed in the battery shaft O direction, and a movable jig 93 that can be moved in the battery shaft O direction together with the second drawing die 92 is provided.

The first drawing die 91 is formed with a drawing hole 94 that penetrates the first drawing die 91 along the battery shaft O direction. The diaphragm hole 94 is formed in an L-shape in a plan view corresponding to the shape of the electrode body 11. The opening size of the drawing hole 94 corresponds to the size obtained by adding twice the thickness of the sealing portion 51 to the outer size of the accommodating portion 50.

The second drawing die 92 is formed in an L-shape in a plan view, which is smaller than the opening size of the drawing hole 94. The upper surface of the second drawing die 92 is a mounting surface 92a on which the battery 10B is mounted after molding.
The movable jig 93 can be inserted into the drawing hole 94 from above, and for example, the post-molding battery 10B mounted on the mounting surface 92a is drawn to the second drawing by the urging force of the urging member 95 such as a coil spring. It is possible to sandwich and fix the mold 92 with a predetermined stress.
The movable jig 93 is movable in the battery shaft O direction together with the second drawing die 92 while maintaining the state in which the battery 10B is fixed after molding.

When the drawing die 90 configured as described above is used to draw the sealing portion 51, as shown in FIG. 13, the molded battery 10B is used in the second drawing die 92. After mounting on the mounting surface 92a, the battery 10B after molding is sandwiched between the second drawing die 92 and fixed by the movable jig 93.
Next, as shown in FIG. 14, the second drawing die 92 and the movable jig 93 are moved upward with respect to the first drawing die 91. As a result, the battery 10B after molding can be inserted into the drawing hole 94, and after molding so as to pass through the inside of the drawing hole 94 while drawing the sealing portion 51 using the inner surface of the drawing hole 94. The battery 10B can be moved.

As a result, an external force can be applied to the sealing portion 51 so that the entire sealing portion 51 is reduced in diameter inside the battery, and the entire sealing portion 51 can be drawn and molded. Therefore, the above-mentioned gap S can be filled, and the sealing portion 51 can be brought into close contact with the portion of the peripheral wall portion 57 of the accommodating portion 50 excluding the rear wall portion 57a from the outside of the battery. The secondary battery 10 shown in 2 can be obtained.

(Action of mobile information terminal and secondary battery)
According to the secondary battery 10 configured as described above, as shown in FIG. 2, since the first electrode terminal plate 72 and the second electrode terminal plate 73 are exposed to the outside, these first electrode terminal plates are exposed to the outside. The 72 and the second electrode terminal plate 73 can each function as external connection terminals. As a result, the secondary battery 10 can be used by using the first electrode terminal plate 72 and the second electrode terminal plate 73. Therefore, the secondary battery 10 can be easily incorporated in the casing 2 and the assembling property can be easily improved. Further, since it is not necessary to make the external connection terminal project from the sealing portion 51 toward the outside of the battery, it is easy to reduce the size of the secondary battery 10.

In particular, in the secondary battery 10 of the present embodiment, since the exterior body 13 is formed by using the laminated film 12, the sealing portion 51 is highly sealed by joining the laminated films 12 to each other by heat welding or the like. It can be configured by sex (adhesion). In addition, since the sealing portion 51 is bent, disturbance of dust, moisture, etc. from the outside into the accommodating portion 50 through between the laminated films 12 (that is, between the upper laminated film 12A and the lower laminated film 12B). Can be effectively prevented from invading. Therefore, the secondary battery 10 with stable operation reliability can be obtained.
Further, since the exterior body 13 is formed by using the thin laminated film 12, the thickness itself of the peripheral wall portion 57 and the sealing portion 51 can be reduced. Therefore, it is easy to reduce the diameter of the secondary battery 10.

Moreover, since the sealing portion 51 in which the laminated films 12 are joined is bent according to the outer shape of the electrode body 11, the size of the accommodating portion 50 accommodating the electrode body 11 is not changed, and the entire secondary battery 10 is used. Can be miniaturized. Therefore, the volume ratio of the electrode body 11 to the total volume of the secondary battery 10 can be improved, and the volume efficiency can be improved.
In addition, since the sealing portion 51 is brought into contact with the peripheral wall portion 57 from the outside of the battery, the peripheral wall portion 57 is surrounded without leaving a gap S (see FIG. 12) between the sealing portion 51 and the peripheral wall portion 57. The sealing portion 51 can be arranged. Therefore, since the gap S can be omitted, the secondary battery 10 can be further miniaturized, which can lead to further improvement in volumetric efficiency.

In particular, the electrode body 11 has an L-shaped external shape in a plan view including the first extension portion 11a and the second extension portion 11b. Therefore, it is possible to form the electrode body 11 in an outer shape other than the square shape (rectangular shape in a plan view, etc.) that has been generally formed in the past, and as shown in FIG. 1, it is planned to be installed in the casing 2. The outer shape can be made to correspond to the space provided.
Therefore, the degree of freedom in the shape of the electrode body 11 can be increased, and it is possible to flexibly meet the demands of design restrictions of various parts mounted in the casing 2 of the portable information terminal 1, and it is an easy-to-use secondary. It can be the battery 10.

Specifically, according to the mobile information terminal 1 of the present embodiment, as shown in FIG. 1, the space space R defined between the first extension portion 11a and the second extension portion 11b is used. Since the back camera module 4 can be arranged, the back camera module 4 and the secondary battery 10 can be efficiently arranged in the casing 2, and the secondary battery 10 can be arranged in the limited installation space in the casing 2. A large proportion of the battery 10 can be secured. Therefore, the portable information terminal 1 having improved battery performance can be obtained without changing the size of the entire casing 2.

As described above, according to the secondary battery 10 of the present embodiment, the electrode body 11 has a high degree of freedom in shape, and can be miniaturized to further improve the volumetric efficiency of the laminated type secondary battery. Can be. Therefore, it can be suitably used for a portable information terminal 1 such as a smartphone, and a high-performance secondary battery 10 having a high volume capacity density can be obtained.

Although the embodiments of the present invention have been described above, these embodiments are presented as examples and are not intended to limit the scope of the invention. The embodiment can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the gist of the invention. The embodiments and modifications thereof include, for example, those that can be easily assumed by those skilled in the art, those that are substantially the same, those that have an equal range, and the like.

For example, in the above embodiment, the secondary battery 10 has been described as an example of the electrochemical cell, but the present invention is not limited to this case, and is, for example, a capacitor (for example, a lithium ion capacitor) or a primary battery. It doesn't matter.

Further, in the above embodiment, the mobile information terminal 1 such as a smartphone has been described as an example of the electronic device, but the present invention is not limited to this case, and the secondary battery 10 is mounted on other electronic devices. It doesn't matter.

Further, in the above embodiment, the case where the shape of the electrode body 11 is formed into an L-shape in a plan view has been described as an example, but the present invention is not limited to this case. For example, by connecting the second extending portion 11b extending along the second direction L2 to the central portion of the first extending portion 11a extending along the first direction L1, the electrode body is formed in a T-shape in a plan view. It may be formed. Further, a plurality of second extension portions 11b extending along the second direction L2 are connected to the first extension portion 11a at intervals in the first direction L1 to form an E-shape in a plan view. An electrode body may be formed.

Further, in the above embodiment, the case where the sealing portion 51 is brought into contact with the peripheral wall portion 57 from the outside of the battery has been described as an example, but the present invention is not limited to this case. For example, as shown in FIG. 15, the secondary battery 100 may have a gap S between the peripheral wall portion 57 and the sealing portion 51. However, in order to reduce the diameter and size of the secondary battery 100, it is preferable that the sealing portion 51 is brought into contact with the peripheral wall portion 57 from the outside of the battery as in the above embodiment.

Further, in the above embodiment, one laminated film 12 is used to form the exterior body 13, but the present invention is not limited to this case. For example, two laminated films 12 are used to form the exterior body 13. It doesn't matter.
In this case, as shown in FIG. 16, the secondary battery 110 may be formed so as to surround the peripheral wall portion 57 from the outside of the battery over the entire circumference. When manufacturing the secondary battery 110 in this case, for example, two laminated films 12 are laminated in the battery axis O direction with the electrode body 11 in between, and then the two laminated films 12 are heat-welded to each other. The sealing portion 51 can be formed by joining with the above. Then, by bending the sealing portion 51 in the molding die 80 according to the outer shape of the electrode body 11, the sealing portion 51 is formed so as to surround the peripheral wall portion 57 from the outside over the entire circumference. Can be done.
As described above, since the exterior body 13 can be formed by using the two laminated films 12, it is easy to improve the manufacturing efficiency of the secondary battery 110.

Further, in the above embodiment, the first electrode terminal plate 72 and the second electrode terminal plate 73 are formed so as to be exposed upward on the top wall portion 60 of the upper laminated film 12A, but the present invention is not limited to this case. ..
For example, as shown in FIG. 17, a secondary battery 120 may be used in which the positive electrode terminal tab 23 and the negative electrode terminal tab 33 are pulled out through between the upper laminated film 12A and the lower laminated film 12B.

In this case, the secondary battery 120 has a bottom of the sealing portion 51 in which the front sealing portion 51a located on the front side of the second extending portion 11b of the electrode body 11 is not bent upward. It is located on the same plane as the wall portion 56. Then, in the front sealing portion 51a, the positive electrode terminal tab 23 and the negative electrode terminal tab 33 are arranged so as to project forward.
Even with the secondary battery 120 configured in this way, the same effects of the above-described embodiment can be achieved. Further, for example, a protection circuit (not shown) can be combined by using the front sealing portion 51a, and the protection circuit can be electrically connected to the positive electrode terminal tab 23 and the negative electrode terminal tab 33.

When manufacturing the secondary battery 120 in this case, for example, as shown in FIG. 18, the first mold 81 and the second mold 82 are passed through the positive electrode terminal tab 23 and the negative electrode terminal tab 33. It is preferable to form the holes 121 in the battery shaft O direction. Further, it is preferable to form a support base 122 for supporting the front sealing portion 51a on the upper surface of the punch portion main body 86.
By configuring the molding die 80 in this way, the portion of the sealing portion 51 other than the front sealing portion 51a can be appropriately bent upward, and the positive electrode terminal tab 23 and the negative electrode terminal tab 33 can be bent. It is possible to avoid inconveniences such as bending.

However, the present invention is not limited to this case, and for example, instead of forming the passage holes 121 in the first mold 81 and the second mold 82, the protruding lengths of the positive electrode terminal tab 23 and the negative electrode terminal tab 33 are increased. In consideration, the opening size of the first forming hole 84 and the second forming hole 85 may be increased.

R ... Space Space L1 ... First direction L2 ... Second direction 1,100,110,120 ... Mobile information terminal (electronic device)
2 ... Casing (housing case)
4 ... Back camera module (functional module)
10 ... Secondary battery (electrochemical cell)
11 ... Electrode body 11a ... First extension part 11b ... Second extension part 12 ... Laminate film 12a ... Metal layer 12b ... Inner resin layer (resin layer)
12c ... Outer resin layer (resin layer)
13 ... Exterior body 20 ... Positive electrode 30 ... Negative electrode 50 ... Accommodating part 51 ... Sealing part 55 ... Top wall part 56 ... Bottom wall part 57 ... Peripheral wall part,
72 ... 1st electrode terminal plate (positive electrode electrode plate)
73 ... Second electrode terminal plate (negative electrode plate)

Claims (5)

An electrode body having a positive electrode and a negative electrode,
A metal layer and an exterior body formed of a laminate film having a resin layer covering both surfaces of the metal layer and accommodating the electrode body inside.
The exterior body includes an accommodating portion for accommodating the electrode body inside, and a sealing portion for sealing the inside of the accommodating portion by joining the laminated films to each other in an overlapping state.
The electrode body extends in a first extending portion extending in the first direction and a second extending direction intersecting the first direction in a plan view from the battery axis direction, and is connected to the first extending portion. With at least the second extension provided
The accommodating portion is bent according to the outer shape of the electrode body with the top wall portion and the bottom wall portion facing the battery axis direction with the electrode body interposed therebetween, and the electrode body is bent from the outside over the entire circumference. With a surrounding wall,
The electrochemical cell is characterized in that the sealing portion is bent according to the outer shape of the electrode body and is formed so as to further surround the peripheral wall portion from the outside. In the electrochemical cell according to claim 1,
The sealing portion is an electrochemical cell formed so as to surround the peripheral wall portion from the outside over the entire circumference. In the electrochemical cell according to claim 1 or 2.
The sealing portion is an electrochemical cell in contact with the peripheral wall portion from the outside. In the electrochemical cell according to any one of claims 1 to 3,
The top wall portion or the bottom wall portion is provided with a positive electrode plate that is electrically connected to the positive electrode and is exposed to the outside, and is electrically connected to the negative electrode and is externally exposed. An electrochemical cell provided with an exposed negative electrode plate. The electrochemical cell according to any one of claims 1 to 4.
A housing case for accommodating the electrochemical cell and
A functional module arranged in the housing case is provided.
The functional module is an electronic device characterized in that the functional module is arranged by utilizing a space defined between the first extension portion and the second extension portion intersecting with each other.

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