JP2001185096A - Cell and method of manufacturing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cell and method of manufacturing the same having a simple structure and enabling to be easily manufactured. SOLUTION: A cell element 20, in which a positive electrode 21 having a positive electrode combination layer 21a and a positive electrode current collection layer 21b and a negative electrode 22 having a negative electrode combination layer 22a and a negative electrode collection layer 22b are laminated through an electrolyte 23, is housed within an inside of an external member 10. A portion of the external member 10 adjacent to the positive electrode current collection layer 21b has an opening 11 and a portion of the external member 10 adjacent to the negative electrode collection layer 22b has an opening 12. Accordingly, the positive electrode collection layer 21b and the negative electrode collection layer 22b are partially exposed via the openings 11, 12. The exposed portions of the positive electrode collection layer 21b and the negative electrode collection layer 22b can electrically be connected to outside to function respectively as electrode terminals.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a battery in which a battery element provided with an electrolyte together with a positive electrode and a negative electrode is covered with an exterior member, and a method of manufacturing the same.

[0002]

2. Description of the Related Art In recent years, portable electronic devices such as a camera-integrated VTR (video tape recorder), a mobile phone, and a laptop computer have been rapidly becoming widespread. There is a need for higher performance chemical devices.

Conventionally, in an electrochemical device such as a secondary battery, a liquid electrolyte in which an electrolyte salt is dissolved in water or a flammable organic solvent or the like (hereinafter, referred to as an electrolyte) is used as a substance for controlling ion conduction. I have been.

FIG. 14 shows an example of the structure of a conventional secondary battery. This secondary battery is a so-called cylindrical type, and has a substantially hollow columnar shape. Inside a battery can 111 having one end closed and the other end open, a strip-shaped positive electrode 121 and a negative electrode 122 are electrolyzed. Wound electrode body 12 wound via a separator 123 impregnated with a liquid (not shown)
It has 0. Inside the battery can 111, a pair of insulating plates 112 and 113 are respectively arranged perpendicular to the winding peripheral surface so as to sandwich the winding electrode body 120. Battery can 1
At the open end of the battery 11, a battery cover 114 is provided.
4 and a PTC provided inside the PTC 4
A (Positive Temperature Coefficient) element 116 is attached by caulking via a gasket 117, and the inside of the battery can 111 is sealed.

[0005] The wound electrode body 120 is provided with a center pin 124.
, The positive electrode lead 125 is pulled out from the positive electrode 121, and the negative electrode lead 12 is pulled out from the negative electrode 122.
6 has been pulled out. The positive electrode lead 125 is electrically connected to the battery lid 114 by welding to the safety valve mechanism 115, and the negative electrode lead 126 is welded to and electrically connected to the battery can 111.

[0006]

In such a conventional secondary battery, there is a problem such as liquid leakage due to the use of an electrolytic solution, and the hermeticity is reduced by using a metal battery can 111 and a battery cover 114. It had to be strictly secured. For this purpose, through a complicated process such as welding, the positive electrode lead 125
And the negative electrode lead 126 was attached. That is,
Generally, the conventional secondary battery has a problem that the weight is large, the manufacturing process is complicated, and the degree of freedom of the shape is low.

[0007] Therefore, research has been actively conducted recently.
It is desired to develop a battery having a simple structure that does not require a complicated manufacturing process using a so-called solid electrolyte or the like.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a battery having a simple structure, which can be easily manufactured, and a method for manufacturing the battery.

[0009]

A battery according to the present invention is a battery in which a battery element provided with an electrolyte together with a positive electrode and a negative electrode is covered by an exterior member, and at least one of the positive electrode and the negative electrode is formed of a battery element. It has a current collector layer constituting one end, and an opening is selectively provided in a portion corresponding to the current collector layer of the exterior member, so that the current collector layer is exposed to the outside through this opening. It was done.

Another battery according to the present invention is a battery in which an electrode body provided with an electrolyte together with a positive electrode and a negative electrode is covered by an exterior member, and is provided on a side of a surface facing at least one of the exterior members of the positive electrode and the negative electrode. A conductor layer is disposed on the outer member, and an opening is selectively provided in a portion corresponding to the conductor layer of the exterior member, and the conductor layer is exposed to the outside through the opening.

[0011] The method for producing a battery according to the present invention is a method for producing a battery in which a battery element provided with an electrolyte together with a positive electrode and a negative electrode is covered with an exterior member. And a step of producing a battery element such that the current collector layer is one end face, a step of forming an opening in the exterior member, and disposing the opening formed in the exterior member on the current collector layer. Covering the battery element with an exterior member so that the current collector layer is selectively exposed through the opening.

Another method for manufacturing a battery according to the present invention is a method for manufacturing a battery in which an electrode body provided with an electrolyte together with a positive electrode and a negative electrode is covered with an exterior member, comprising a step of forming an opening in the exterior member. Forming a conductor layer so as to cover an opening formed in the exterior member, and forming an electrode on the exterior member on which the conductor layer is formed so that the conductor layer and the positive electrode or the negative electrode are electrically connected. And a step of covering the body.

In the battery according to the present invention, a current collector layer is provided on at least one of the positive electrode and the negative electrode, and an opening is selectively provided in a portion corresponding to the current collector layer forming region of the exterior member. Therefore, the current collector layer is partially exposed.

In another battery according to the present invention, a conductor layer is provided on the surface of at least one of the positive electrode and the negative electrode facing the exterior member, and selectively provided in a region corresponding to the conductor layer of the exterior member. Is provided with an opening, so that the conductor layer is partially exposed.

In the method of manufacturing a battery according to the present invention, the opening formed in the exterior member is arranged on the current collector layer of the positive electrode or the negative electrode, and the battery is formed by the external member so that the current collector layer is selectively exposed. The element is covered.

In another method of manufacturing a battery according to the present invention, a conductor layer is formed so as to cover an opening formed in an exterior member, and the conductor layer is electrically connected to a positive electrode or a negative electrode. The exterior body covers the electrode body.

[0017]

Embodiments of the present invention will be described below in detail with reference to the drawings. Here, an example of a secondary battery in which lithium (Li) is inserted and extracted from the negative electrode will be described.

[First Embodiment] FIG. 1 shows a plan structure of a battery 1 according to a first embodiment of the present invention, and FIG. 2 is a sectional view taken along line II-II of FIG. FIG. The battery 1 includes an exterior member 10 and a battery element 20 housed inside the exterior member 10. The battery element 20 includes, for example, a thin plate-shaped positive electrode 21 having a positive electrode mixture layer 21a and a positive electrode current collector layer 21b, and a thin plate-shaped negative electrode 22 having a negative electrode mixture layer 22a and a negative electrode current collector layer 22b. 23 are stacked.

The exterior member 10 is composed of, for example, two rectangular films 10a and 10b (see FIG. 2). These two films 10a and 10b have the same size, for example, and their outer edges are adhered to each other by fusion bonding or an adhesive. In addition, the gap between the end of the exterior member 10 and the battery element 20 is filled with the sealing material 30, and the exterior member 10 and the electronic element 20 are in close contact with each other via the sealing material 30. .

An opening 11 is provided in a portion of the exterior member 10 adjacent to the positive electrode 21, more specifically, the positive electrode current collector layer 21b.
Is provided. In addition, an opening 12 is provided in a portion adjacent to the negative electrode 22, more specifically, the negative electrode current collector layer 22b. Therefore, the positive electrode current collector layer 21b and the negative electrode current collector layer 22b are partially exposed through these openings 11 and 12. The exposed portions of the positive electrode current collector layer 21b and the negative electrode current collector layer 22b can be electrically connected to the outside and function as electrode terminals.

Although FIGS. 1 and 2 show the square openings 11 and 12, the shapes of the openings 11 and 12 are not limited to the square, but may be other shapes such as a circle. Further, the shapes of the opening 11 and the opening 12 may be different from each other.

Exterior member 10 (films 10a and 10b)
Is formed of, for example, a laminate film in which a polymer compound film, a metal film, and a polymer compound film are laminated in this order. Examples of the constituent material of the polymer compound film include polyolefin resins such as polyethylene and polypropylene, nylon (polyamide-based synthetic resin), vinyl acetate-based resin, acrylic resin, and epoxy resin. Further, the metal film preferably has a function of preventing outside air (particularly, moisture) from entering the inside of the exterior member 10, and an aluminum (Al) foil or the like is appropriate. The purpose of preventing the invasion of the outside air is to prevent the battery performance from deteriorating due to the reaction between lithium and water or nitrogen contained in the outside air.

The package member 10 may be made of a film made of only a polymer compound and having a thickness of, for example, about 50 μm, instead of the above-described laminate film. When such a thin film is used, the volume energy density of the battery 1 can be increased as compared with the case where an exterior member made of a metal material or a laminated film is used. In addition, there is an advantage that fusion can be easily performed in an exterior member fusion step during manufacturing described later. In addition, as the high molecular compound, the same material as the constituent material of the high molecular compound film of the laminate film described above can be used.

The positive electrode 21 has a structure in which, for example, a positive electrode mixture layer 21a is provided on the surface of the positive electrode current collector layer 21b made of aluminum foil on the side of the electrolyte 23. Positive electrode mixture layer 2
1a is, for example, a positive electrode active material, a conductive agent such as graphite,
It is configured to contain a binder such as polyvinylidene fluoride. As the positive electrode active material, for example, a lithium composite oxide or a lithium composite sulfide is preferable. In particular,
To increase the energy density, a lithium composite oxide mainly composed of Li _x MO ₂ is preferable. M is preferably one or more transition metals, specifically, at least one of cobalt (Co), nickel (Ni), and manganese (Mn). Also, x is usually 0.05 ≦ x ≦
It is a value within the range of 1.12. In addition, the positive electrode current collector layer 21
In addition to functioning as a current collector, b also plays a role in preventing outside air from entering.

The positive electrode 21 is not limited to the structure shown in FIG.
If it is provided, other structures may be used. For example,
As shown in FIG. 3, in addition to the positive electrode current collector layer 21b and the positive electrode mixture layer 21a, on the electrolyte side of the positive electrode mixture layer 21a,
Further, the positive electrode 21A may have a structure in which the positive electrode current collector layers 21c and the positive electrode mixture layers 21d are provided alternately. Incidentally, FIG. 3 shows the positive electrode current collector layer 21c and the positive electrode mixture layer 2c.
Although an example in which two layers 1d are provided is shown, the positive electrode current collector layer 21c and the positive electrode mixture layer 21d may each be one layer, or may be three or more layers each. .

The negative electrode 22 has a structure in which a negative electrode mixture layer 22a is provided on the surface of the negative electrode current collector layer 22b made of, for example, copper (Cu) foil on the side of the electrolyte 23. Negative electrode mixture layer 22
a is configured to include, for example, a material capable of inserting and extracting lithium and a binder such as polyvinylidene fluoride. As a material capable of inserting and extracting lithium, for example, a material containing one or more of a carbonaceous material, a metal oxide, and a polymer material can be given. Among them, a carbonaceous material is preferable because the change in crystal structure that occurs during charge and discharge is very small. In addition, as a carbonaceous material, for example,
Pyrolytic carbon, coke such as pitch coke, needle coke, petroleum coke or coal coke, graphite, glassy carbon, fired organic polymer compound (for example, fired phenol resin or furan resin), carbon Fibers or activated carbon are exemplified.
Examples of the metal oxide include tin oxide (SnO ₂ ), and examples of the polymer material include polyacetylene and polypyrrole. Incidentally, it is also possible to use lithium metal or a lithium alloy instead of these negative electrode materials.

The negative electrode 22 is not limited to the structure shown in FIG. 2, but may have another structure as long as the negative electrode current collector layer 22b is provided closest to the exterior member 10 like the positive electrode 21. It may be.

The electrolyte 23 is, for example, a matrix polymer compound in which a lithium salt is dispersed as an electrolyte salt (a so-called solid polymer electrolyte). Since this polymer solid electrolyte has excellent film moldability,
If this is used, the degree of freedom in shape selectivity is increased.

Examples of the matrix polymer compound include polyvinylidene fluoride, a copolymer of vinylidene fluoride and hexafluoropropylene, a copolymer of vinylidene fluoride and tetrafluoroethylene, or a copolymer of vinylidene fluoride and trifluoroethylene. Suitable are fluorine-based polymer compounds such as copolymers with, ether-based polymer compounds such as polyethylene oxide or a crosslinked product thereof, ester-based polymer compounds such as polymethacrylate, and acrylate-based polymer compounds. One or two or more of them are used in combination.

As the lithium salt, for example, LiP
F ₆ , LiBF ₄ , LiClO ₄ , LiAsF ₆ , Li
B (C ₆ H ₅ ) ₄ , LiCl, LiBr, LiCH ₃ S
O ₃ , LiCF ₃ SO ₃ , LiN (CF ₃ SO ₃ ) ₂ ,
LiC ₄ F ₉ SO ₃ , LiCF ₃ CO ₂ , LiN (CF
₃ CO ₂ ) ₂ is suitable, and one or more of these are used in combination.

Next, a method of manufacturing the battery 1 will be described.

First, a positive electrode mixture is prepared by mixing a positive electrode active material, a conductive agent, and a binder, and the mixture is dispersed in a solvent such as N-methylpyrrolidone to form a positive electrode mixture slurry. The positive electrode 21 is produced by applying the slurry to one surface of the positive electrode current collector layer 21b made of, for example, an aluminum foil, drying and compressing and forming the positive electrode mixture layer 21a.

Next, for example, a material capable of occluding and releasing lithium and a binder are mixed, and the mixture is dispersed in a solvent such as N-methylpyrrolidone to obtain a negative electrode mixture slurry. Is coated on one surface of a negative electrode current collector layer 22b made of, for example, a copper foil, dried, and compression-molded to form a negative electrode mixture layer 22a, thereby producing the negative electrode 22.

When the positive electrode 21A having a structure having a plurality of mixture layers and a current collector layer as shown in FIG. 3 is manufactured, the positive electrode current collector layer 22b of the positive electrode mixture layer 22a is further formed. The positive electrode current collector layer 21c and the positive electrode mixture layer 2
1d are sequentially formed.

After producing the positive electrode 21 and the negative electrode 22,
For example, an ether-based polymer compound such as polyethylene oxide, a lithium salt, and a solvent are prepared. Subsequently, these are mixed, and the obtained mixed solution is applied to the positive electrode mixture layer 21a and the negative electrode mixture layer 22a, respectively, and left for a predetermined time.
The solvent is removed by drying at 0 ° C. for 10 minutes to obtain a so-called polymer solid electrolyte (electrolyte 23) in which a lithium salt is dispersed in a polymer compound. Here, when applying the mixed solution, it is preferable to impregnate the positive electrode mixture layer 21a and the negative electrode mixture layer 22a with the mixed solution. As a result, part of the electrolyte is converted into the positive electrode mixture layer 21a and the negative electrode mixture layer 22a.
Of the cathode 21 and the anode 22 and the electrolyte 2
3 and the positive electrode 21 and the negative electrode 2
This is because the electrical contact between the electrolyte 2 and the electrolyte 23 is improved.

The ether type polymer compound includes
It is preferable to use a compound having a side chain such as oligo-oxyethylene or an amorphous polymer having low crystallinity such as a random copolymer of ethylene oxide and propylene oxide. Further, it is preferable to use one having a crosslinkable functional group such as an acrylate group, an active hydrogen group or an allyl group at the terminal of the polymer chain.

After the formation of the electrolyte 23, these are overlapped with each other so that the surface of the cathode 21 on which the electrolyte 23 is formed and the surface of the anode 22 on which the electrolyte 23 is formed, and further pressed. As a result, the positive electrode 21 and the negative electrode 22
The battery element 20 laminated via is manufactured.

Next, as shown in FIG. 4, for example, two polymer sheets 10c and 10d made of polyethylene or polypropylene are prepared as the exterior member 10. Thereafter, a large number of, for example, square openings 11 are formed in the polymer sheet 10c, and the polymer sheet 10d is formed.
In this case, a large number of, for example, square openings 12 are formed. More specifically, for example, by punching the polymer sheets 10c and 10d with a cutter having a predetermined opening shape, the openings 11 and 12 are separated at predetermined intervals in the width direction and the longitudinal direction of each of the polymer sheets 10c and 10d. Are formed respectively.

As described above, the shape of the openings 11 and 12 is not limited to a quadrangle but may be other shapes, and the area, the formation position, and the like can be appropriately set. The shape, area, position, and the like of the electrode terminal can be made desired according to the shape of the openings 11 and 12.

Openings 11, 11 are formed in the polymer sheets 10c, 10d.
After the formation of the polymer sheets 12, as shown in FIG. 5, the same number of battery elements 20 as the openings 11 and 12 are formed in the polymer sheet 10 c so as to correspond to the openings 11 of the polymer sheet 10 c and the openings 12 of the polymer sheet 10 d. And polymer sheet 1
0d. At this time, the polymer sheet 10c
The electronic element 20 is arranged so that the positive electrode current collector layer 21b is in contact with the polymer sheet 10d and the negative electrode current collector layer 22b. Thereby, the positive electrode current collector layer 21 b
Is exposed, and the negative electrode current collector layer 22 b is exposed from the opening 12. FIG. 5 corresponds to a cross section taken along line VV of FIG.

Finally, as shown in FIG. 6, the polymer sheet 10c and the polymer sheet 10d are fused together so that each battery element 20 is accommodated therein, for example, in a reduced-pressure atmosphere. In between, the polymer sheets 10c and 10d are cut. Here, by filling the sealant 30 between the polymer sheets, the side surface of the battery element 20 and the polymer sheet 10 are interposed via the sealant 30.
c and 10d are brought into close contact with each other. At this time, if the laser irradiation is performed, the polymer sheet 10c and the polymer sheet 10c are formed.
d and heat-fusible, and the polymer sheet 10
It is preferable to use a laser because c and 10d can be cut. Incidentally, as the fusion method, a simple method such as a method of applying heat to the polymer sheets 10c and 10d or propagating ultrasonic waves to perform thermal fusion may be used.

Next, the operation of the battery 1 will be described.

In this battery 1, when charged, the positive electrode 21
Is desorbed as ions from the lithium ions, and is occluded in the anode 22 through the electrolyte 23. When the discharge is performed, lithium is ionized and released from the negative electrode 22 and occluded in the positive electrode 21 through the electrolyte 23. Here, the positive electrode current collector layer 21
b functions as a positive electrode terminal, and the negative electrode current collector layer 22b functions as a negative electrode terminal. Therefore, when charging, external energy is applied to the positive electrode current collector layer 21b or the negative electrode current collector layer 2b.
2b is supplied to the battery element 20, and at the time of discharging, energy is taken out via the positive electrode current collector layer 21b or the negative electrode current collector layer 22b.

As described above, according to the battery 1 of the present embodiment, a so-called polymer solid electrolyte having no risk of liquid leakage is used as the electrolyte 23, and the openings 11 and 12 are formed in the exterior member 10.
Is provided so that the positive electrode current collector layer 21b and the negative electrode current collector layer 22b are partially exposed, so that the positive electrode current collector layer 21b and the negative electrode current collector layer 22b are used as electrode terminals, respectively. Can be. Therefore, unlike a conventional battery, it is not necessary to provide a lead wire, and a simple structure can be obtained. In addition, since a complicated terminal forming step is not required at the time of manufacturing, the terminal can be easily manufactured and productivity can be improved. Furthermore, from the point that the process relating to the fusion of the exterior member 10 can be simplified,
Productivity can be improved.

Since there is no need to provide a lead wire,
The size of the battery 1 can be reduced, and the volume energy density can be improved.

In the battery 1 having the above-described structure, for example, as shown in FIG. 7, the connecting portion 2 formed by filling the opening with a gold paste or a silver paste is used.
Can be connected in series. in this way,
Since the battery 1 according to the present embodiment has a small thickness in the electrode stacking direction, it is effective to use the battery 1 in a case where the batteries 1 are stacked and connected to form a battery pack including a plurality of batteries 1.

[Second Embodiment] FIG. 8 shows a sectional structure of a battery 3 according to a second embodiment of the present invention. This battery 3 is the same as the battery 1 of the first embodiment except that the battery 1 of the first embodiment has an exterior member 50 instead of the exterior member 10 and the anode 22 has an anode 52 instead of the anode 22. It has the same configuration, operation and effect as the embodiment. Therefore, here, the same components as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof will be omitted.

The negative electrode 52 includes, for example, a negative electrode current collector layer 52b functioning as a negative electrode terminal, a negative electrode mixture layer 52a provided on the surface of the negative electrode current collector layer 52b on the electrolyte 23 side, and a negative electrode current collector layer 52b. It has a negative electrode current collector layer 52c and a negative electrode mixture layer 52a provided closer to the exterior member 50 than the layer 52b. The negative electrode mixture layer 52a and the negative electrode current collector layer 52
As the constituent materials of b and 52c, for example, the same materials as the constituent materials of the negative electrode mixture layer 22a and the negative electrode current collector layer 22b of the first embodiment can be used.

The negative electrode current collector layer 52b is led out from the inside of the exterior member 50 to the outside through the joint at the end of the exterior member 50. The negative electrode current collector layer 52b and the exterior member 50 are in close contact with each other so as to prevent outside air from entering. This negative electrode current collector layer 52b is preferably in a mesh shape. This is because the adhesion to the exterior member 50 can be improved.

In this embodiment, since the negative electrode current collector layer 52b led out of the exterior member 50 serves as a negative electrode terminal,
An opening (an opening corresponding to the opening 12 of the first embodiment) is not provided on the negative electrode side of the exterior member 50. In addition,
An opening 51 similar to that of the first embodiment is provided on the positive electrode side.

Next, a method of manufacturing the battery 3 will be described.

First, a positive electrode 21 is manufactured in the same manner as in the first embodiment. Next, after preparing a negative electrode mixture slurry in the same manner as in the first embodiment, this negative electrode mixture slurry is applied to both surfaces of the negative electrode current collector layer 52b made of, for example, copper foil except for one end, and dried. Then, compression molding is performed to form the negative electrode mixture layer 52a. Subsequently, one negative electrode mixture layer 52a
For example, a copper foil is disposed on the surface opposite to the negative electrode current collector layer 52b to form a negative electrode current collector layer 52c, and further, the negative electrode mixture layer 52a
Then, the negative electrode current collector layer 52c is sequentially formed to form the negative electrode 52.

After producing the positive electrode 21 and the negative electrode 52,
The electrolyte 23 is applied, for example, to the surfaces of the positive electrode mixture layer 21a and the negative electrode mixture layer 52a, and these are overlapped so that the surfaces of the positive electrode 21 and the negative electrode 52 where the electrolyte 23 is applied face each other, and further pressed.

Next, for example, two polymer sheets made of polyethylene or polypropylene as the exterior member 50 are prepared. Thereafter, for example, a large number of openings 51 are formed in one of the polymer sheets in the same manner as in the first embodiment. Subsequently, for example, the same number of battery elements as the openings 51 are sandwiched between two polymer sheets so that the openings 51 of the polymer sheet correspond to the battery elements. Finally,
For example, in a reduced pressure atmosphere, the outer edges of the polymer sheet are fused together so as to accommodate each battery element,
The polymer sheet is cut between adjacent battery elements. Also in the present embodiment, by filling the sealant 30 between the polymer sheets, the side surfaces of the electronic element and the polymer sheet are brought into close contact with each other via the sealant 30.

As described above, according to the battery 3 of the present embodiment, the length of the negative electrode current collector layer 52b is longer than the length of the negative electrode mixture layer 52a and the negative electrode current collector layer 52c. Since the layer 52b is led out of the exterior member 50, the negative electrode current collector layer 52b can be used as a negative electrode terminal. Further, similarly to the first embodiment, the positive electrode current collector layer 21b can be used as a positive electrode terminal. Therefore, a simple structure can be obtained. In addition, at the time of manufacturing, a complicated terminal forming step or the like is not required, and a step related to fusion of the exterior member 10 can be simplified,
Productivity can be improved.

[Third Embodiment] FIG. 9 shows a sectional structure of a battery 4 according to a third embodiment of the present invention. The battery 4 includes an exterior member 10 similar to that of the first embodiment, an electrode body 60 and conductor layers 71 and 72 housed inside the exterior member 10. The electrode body 60 is configured by, for example, laminating a positive electrode 61 and a negative electrode 62 via an electrolyte (for example, a so-called polymer solid electrolyte) 63.

The conductor layer 71 is disposed, for example, between the positive electrode 61 and the exterior member 10 so as to be adjacent to each other, and is formed of a metal foil such as an aluminum foil. The conductor layer 71 has a thickness of, for example, 10 μm.
m or more and is electrically connected to the positive electrode 61. A part of the region of the exterior member 10 adjacent to the conductor layer 71 includes:
An opening 11 is provided, and the conductor layer 71
Partially exposed through. The exposed portion of the conductor layer 71 is electrically connectable to the outside, and functions as a positive electrode terminal. The conductor layer 71 also functions as a current collector of the positive electrode 61.

The conductor layer 72 is disposed, for example, between the negative electrode 62 and the package member 10 so as to be adjacent to each other, and is formed of a metal foil such as a copper foil. The conductor layer 72 has a thickness of, for example, 10 μm or more, and is electrically connected to the negative electrode 62. Exterior member 1
In part of the region adjacent to the conductive layer 72 of
Is provided, and the conductor layer 72 is partially exposed through the opening 12. The exposed portion of the conductor layer 72 is electrically connectable to the outside and functions as a negative electrode terminal. The conductor layer 72 also functions as a current collector of the negative electrode 62.

The conductor layers 71 and 72 are not limited to aluminum foil and copper foil, and may be made of another material having conductivity such as nickel, stainless steel or iron (Fe). It is possible.

The positive electrode 61 is the same as the positive electrode 21 of the first embodiment.
And the same positive electrode active material. This positive electrode 61
For example, similarly to the first embodiment, it is composed of a mixture layer and a current collector layer. Further, in the present embodiment, since the conductor layer 71 has the function of the positive electrode current collector, the conductor layer 71 may be constituted only by the mixture layer. Similarly, the negative electrode 62
In this case, it may be constituted by a mixture layer and a current collector layer, or may be constituted only by a mixture layer.
Incidentally, the negative electrode mixture layer can be formed using the same material as the negative electrode mixture layer 22b of the first embodiment.

The electrolyte 63 and the sealant 30 have the same structure, operation and effect as those of the electrolyte 23 and the sealant 30 of the first embodiment, respectively, and the description thereof is omitted here. I do.

Next, a method of manufacturing the battery 4 will be described.

First, for example, a positive electrode mixture slurry is prepared in the same manner as in the first embodiment, and this positive electrode mixture slurry is applied to both sides of, for example, an aluminum foil, dried, and compression molded to form a positive electrode 61. Make it. Next, a negative electrode mixture slurry was prepared in the same manner as in the first embodiment, and the negative electrode mixture slurry was applied to both sides of a copper foil and dried, for example.
The negative electrode 62 is manufactured by compression molding.

After producing the positive electrode 61 and the negative electrode 62,
For example, an electrolyte 63 is prepared in the same manner as in the first embodiment, and the electrolyte 63 is applied to the positive electrode 61 and the negative electrode 62.
Subsequently, the surface of the positive electrode 61 on which the electrolyte 63 is formed and the negative electrode 62
These are overlapped so that the surface on which the electrolyte 63 is formed faces each other, and further pressed. Thus, an electrode body 60 in which the positive electrode 61 and the negative electrode 62 are stacked via the electrolyte 63 is produced.

Next, as shown in FIG. 10, two polymer sheets 10c and 10b are prepared, and a large number of openings 11, 1 are provided.
2 are formed. Subsequently, for example, the same number of aluminum foils as the openings 11 are fused to the polymer sheet 10c so as to correspond to the openings 11, thereby forming the conductor layers 71. In addition, the conductor layers 72 are formed by fusing, for example, the same number of copper foils as the openings 12 to the polymer sheet 10 d so as to correspond to the openings 12.

In this way, the polymer sheet 10c and the conductor layer 71, and the polymer sheet 10d and the conductor layer 72
Then, the electrode body 60 is sandwiched between the polymer sheet 10c and the polymer sheet 10d so as to correspond to the conductor layers 71 and 72. The subsequent steps are the same as in the first embodiment.

Next, the operation of the battery 4 will be described.

In the battery 1, when charged, the positive electrode 61
Is ionized and desorbed from the lithium ion, and occluded in the negative electrode 62 via the electrolyte 63. When the discharge is performed, lithium is ionized and released from the negative electrode 62 and is stored in the positive electrode 61 through the electrolyte 63. Here, since the conductor layer 71 functions as a positive electrode terminal and the conductor layer 72 functions as a negative electrode terminal, during charging, external energy is applied to the electrode body via the conductor layer 71 or the conductor layer 72. 60, and at the time of discharge, energy is taken out via the conductor layer 71 or the conductor layer 72.

As described above, according to battery 4 of the present embodiment, conductor layer 71 is provided between positive electrode 61 and exterior member 10, and conductor layer 72 is provided between negative electrode 62 and exterior member 10. Since the conductive layers 71 and 72 are provided so as to partially expose the conductive layers 71 and 72, the conductive layers 71 and 72 can be used as electrode terminals. Therefore, a simple structure can be obtained. Further, since there is no need to provide a lead wire, the size of the battery 4 can be reduced, and the volume energy density can be improved. Further, since a complicated terminal forming step or the like is not required at the time of manufacturing, the terminal can be easily manufactured and productivity can be improved.

In the battery 4 of the present embodiment,
For example, the batteries can be connected to each other by filling the openings 11 and 12 with a gold paste or a silver paste, respectively.

[Fourth Embodiment] FIG. 11 shows a plan structure of a battery 5 according to a fourth embodiment of the present invention, and FIG. 12 is a sectional view taken along line XII-XII of FIG. FIG. The battery 5 includes an exterior member 80 and
And a battery element 90 housed inside the exterior member. Note that the end of the exterior member 80 and the side surface of the battery element 90 are in close contact with each other via the sealing material 30. Battery element 90
For example, a belt-like positive electrode 91 and a negative electrode 92
Are laminated and wound. Here, the positive electrode 91
, And the length of the positive electrode 91 in the longitudinal direction is longer than that of the negative electrode 92.

The positive electrode 91 is, for example, a positive electrode current collector layer 91b.
And a positive electrode mixture layer 91a provided on the electrolyte 93 side of the positive electrode current collector layer 91b. Note that the positive electrode current collector layer 91b and the positive electrode mixture layer 91a are respectively configured in the same manner as the positive electrode current collector layer 21b and the positive electrode mixture layer 21a of the first embodiment.

The negative electrode 92 is, for example, similar to the positive electrode 91,
Negative electrode current collector layer 92b and electrolyte 9 of negative electrode current collector layer 92b
And a negative electrode mixture layer 92a provided on the third side. Note that the negative electrode current collector layer 92b and the negative electrode mixture layer 92a are configured in the same manner as the negative electrode current collector layer 22b and the negative electrode mixture layer 22a of the first embodiment.

As described above, since the length of the positive electrode 91 is longer than the length of the negative electrode 92, the vicinity of the outermost end of the wound battery element 90 is close to the positive electrode 91 and the negative electrode 92. There is a step S between them. On the end side of the step S,
The positive electrode 91, more specifically, the positive electrode current collector layer 91 b is located on the outermost side of the battery element 90. Further, on the side opposite to the end from the step S, the negative electrode 92, more specifically, the negative electrode current collector layer 92 b is located on the outermost side of the battery element 90.

In the present embodiment, openings 81 and 82 are provided in the exterior member 80 in regions corresponding to the end side of the above-described step S and the opposite side thereof, respectively. The negative electrode current collector layer 92b has openings 81,
Each is partially exposed through 82. The exposed portions of the positive electrode current collector layer 91b and the negative electrode current collector layer 92b are electrically connectable to the outside and function as electrode terminals.

The electrolyte 93 and the sealant 30 have the same structure, operation and effect as those of the electrolyte 23 and the sealant 30 of the first embodiment, respectively, and the description thereof is omitted here. I do. The operation of the battery 5 according to the present embodiment is the same as that of the battery 1 according to the first embodiment, and a description thereof will be omitted.

As described above, according to the battery 5 according to the present embodiment, the positive electrode 91 and the negative electrode 92 having a shorter length than the positive electrode 91 are wound around the outer peripheral member near the outermost end. Since the positive electrode current collector layer 91b and the negative electrode current collector layer 92b are partially exposed through the openings 81, 81, respectively, the positive electrode current collector layer 91b and the negative electrode current collector layer 92 are formed.
b can be used as electrode terminals.

As described above, the present invention has been described with reference to the embodiments. However, the present invention is not limited to the above embodiments, and can be variously modified. For example, in the first to third embodiments, the polymer sheets 10c and 10d are cut by using a laser or the like.
As shown in FIG. 3, if a sewing machine (stitch) M is inserted in advance at a position to be cut, the polymer sheet can be cut easily. At this time, the sewing machines M are preferably provided at predetermined intervals so that the pattern of the current collector layer or the conductor layer is smaller than the interval between the sewing machines M. This is because a margin for sealing the battery element 20 (electrode body 60) can be provided by fusing the polymer sheets 10c and 10d.

In each of the above embodiments, an electrolyte in which a lithium salt is dispersed in a matrix polymer compound is used. However, a solid inorganic electrolyte may be used. Alternatively, the electrolyte can be used in a gel form in which an electrolyte is held in a polymer compound. However, in that case, it is preferable that the water content is low and the viscosity is high.

Further, in each of the above embodiments, the positive electrode current collector layer is made of aluminum foil, and the negative electrode current collector layer is made of copper foil. It may be made of another conductive material that is stable to light. Such materials include, for example, nickel and stainless steel.

In each of the above embodiments, the case where the exterior members are brought into close contact with each other by fusion has been described. However, the exterior members may be brought into close contact with each other by using another method such as a method of bringing into close contact with an adhesive. .

In each of the above embodiments, the case where the current collector layer or the conductor layer having the exposed portion is adjacent to the exterior member has been described. However, the current collector layer or the conductor layer and the exterior member are adjacent to each other. Even if another layer is provided between them, the effect of the present invention can be obtained by partially exposing the current collector layer or the conductor layer through the opening of the exterior member. .

Further, in the third embodiment, the positive electrode 61
Although the conductor layers 71 and 72 are provided on both sides of the negative electrode 62 and the negative electrode 62, in the same manner as in the second embodiment, in one electrode, the current collector layer is led out of the exterior member. This may be used as an electrode terminal.

In addition, in each of the above embodiments, the description has been given by taking as an example a secondary battery (lithium ion secondary battery) that inserts / extracts lithium at the negative electrode. However, the present invention relates to a charge carrier other than lithium ion. The invention is also widely applied to batteries using.

[0085]

As described above, according to the battery according to any one of claims 1 to 10, at least one of the positive electrode and the negative electrode has a current collector layer constituting one end of the battery element. And an opening is selectively provided in a portion corresponding to the current collector layer of the exterior member, so that the current collector layer is exposed to the outside through this opening, so that the current collector layer is used as an electrode terminal. Can be used. Therefore, there is no need to provide a lead wire or the like as an electrode terminal, and an effect that a simple structure can be obtained is achieved. In addition, the size of the battery can be reduced, and the volume energy density can be improved.

According to the battery according to any one of the eleventh to sixteenth aspects, the conductor layer is disposed on the side of the surface facing at least one of the exterior members of the positive electrode and the negative electrode, An opening is selectively provided in a portion of the exterior member corresponding to the conductor layer, and the conductor layer is exposed to the outside through the opening, so that the conductor layer can be used as an electrode terminal. Therefore, there is no need to provide a lead wire or the like as an electrode terminal, and an effect that a simple structure can be obtained is achieved.

Further, according to the battery manufacturing method of any one of the seventeenth to twentieth aspects, the current collector layer formed on at least one of the positive electrode and the negative electrode is selectively exposed. In addition, since the battery element is covered by the exterior member, unlike the conventional manufacturing method, the battery element can be easily manufactured without a complicated manufacturing process, and the effect of improving productivity can be achieved.

In addition, according to the battery manufacturing method of any one of the twenty-first to twenty-fourth aspects, a conductor layer is formed so as to cover the opening formed in the exterior member. Since the electrode body is covered by the exterior member so that the electrode and the positive electrode or the negative electrode are electrically connected, unlike the conventional manufacturing method, it can be easily manufactured without a complicated manufacturing process. This has the effect of improving productivity.

[Brief description of the drawings]

FIG. 1 is a plan view illustrating a configuration of a battery according to a first embodiment of the present invention.

FIG. 2 is a sectional view taken along line II-II in FIG.

FIG. 3 is a cross-sectional view illustrating a structure of a positive electrode according to a modified example of the positive electrode of the battery illustrated in FIG.

FIG. 4 is a plan view for explaining one step of the method for manufacturing the battery according to the first embodiment of the present invention.

FIG. 5 is a cross-sectional view for explaining a manufacturing step following FIG. 4;

FIG. 6 is a cross-sectional view for explaining a manufacturing step following FIG. 5;

7 is a cross-sectional view illustrating a configuration when the batteries illustrated in FIG. 1 are connected.

FIG. 8 is a sectional view illustrating a configuration of a battery according to a second embodiment of the present invention.

FIG. 9 is a sectional view illustrating a configuration of a battery according to a third embodiment of the present invention.

FIG. 10 is a plan view for explaining one step of a method for manufacturing a battery according to the third embodiment of the present invention.

FIG. 11 is a plan view illustrating a configuration of a battery according to a fourth embodiment of the present invention.

FIG. 12 is a sectional view taken along line XII-XII of FIG.

FIG. 13 is a plan view for explaining one step of another method of manufacturing the battery according to the first to third embodiments of the present invention.

FIG. 14 is a cross-sectional view illustrating a configuration example of a conventional battery.

[Explanation of symbols]

1, 3, 4, 5 ... battery, 2 ... connecting part, 10, 50, 80
... Exterior members, 10c, 10d ... Polymer sheets, 11,1
2, 51, 81, 82 ... opening, 20, 90 ... battery element,
21, 21A, 61, 91 ... positive electrode, 21a, 21d, 9
1a: Positive electrode mixture layer, 21b, 21c, 91b: Positive electrode collector layer, 22, 92: Negative electrode, 22a, 92a: Negative electrode mixture layer, 22b, 92b: Negative electrode current collector layer, 23, 63, 93
... Electrolyte, 30 ... Sealant, 60 ... Electrode body, 71,72 ...
Conductor layer

 ──────────────────────────────────────────────────続 き Continued on the front page F-term (reference) CJ05 CJ06 DJ02 DJ05 DJ14 EJ01 EJ12

Claims (24)

[Claims] 1. A battery in which a battery element provided with an electrolyte together with a positive electrode and a negative electrode is covered by an exterior member, and at least one of the positive electrode and the negative electrode constitutes one end of the battery element. An opening is selectively provided in a portion corresponding to the current collector layer of the exterior member having a body layer, and the current collector layer is exposed to the outside through the opening. Battery. 2. The device according to claim 1, wherein the current collector layer functions as an electrode terminal that can be electrically connected to the outside.
The battery as described. 3. The battery according to claim 1, wherein the electrolyte contains a polymer compound and an electrolyte salt. 4. The battery according to claim 1, wherein the exterior member contains a polymer compound. 5. The battery according to claim 4, wherein the exterior member is made of a laminate film. 6. The battery according to claim 4, wherein the exterior member is formed of a film made of a polymer compound. 7. The battery according to claim 1, wherein the opening is provided in one of the positive electrode and the negative electrode. 8. The method according to claim 1, wherein the other of the positive electrode and the negative electrode has another current collector layer, and the other current collector layer is led out of the exterior member. Item 7. The battery according to Item 7. 9. The battery according to claim 1, wherein the current collector layer is formed of a metal foil. 10. The battery according to claim 1, comprising a plurality of said battery elements. 11. A battery in which an electrode body provided with an electrolyte together with a positive electrode and a negative electrode is covered by an exterior member, wherein at least one of the positive electrode and the negative electrode has a conductor on a surface facing the exterior member. A battery, wherein a layer is provided, and an opening is selectively provided in a portion of the exterior member corresponding to the conductor layer, and the conductor layer is exposed to the outside through the opening. . 12. The battery according to claim 11, wherein the conductor layer is electrically connected to the positive electrode or the negative electrode and functions as an electrode terminal that can be electrically connected to the outside. 13. The battery according to claim 11, wherein the electrolyte contains a polymer compound and an electrolyte salt. 14. The battery according to claim 11, wherein the conductor layer is formed of a metal foil. 15. The battery according to claim 11, wherein the exterior member contains a polymer compound. 16. The battery according to claim 11, comprising a plurality of said electrode bodies. 17. A method for producing a battery in which a battery element provided with an electrolyte together with a positive electrode and a negative electrode is covered with an exterior member, wherein at least one of the positive electrode and the negative electrode has a current collector layer. Forming the battery element such that the current collector layer is one end face; forming an opening in the exterior member; arranging the opening formed in the exterior member on the current collector layer; Covering the battery element with the exterior member so that the current collector layer is selectively exposed through the opening. 18. The method for manufacturing a battery according to claim 17, wherein an electrolyte containing a polymer compound and an electrolyte salt is used as the electrolyte. 19. The film according to claim 17, wherein a film containing a polymer compound is used as the exterior member.
A method for producing the battery according to the above. 20. The method according to claim 20, wherein in the step of forming an opening in the exterior member, a plurality of openings are formed apart from each other, and in the step of covering the battery element with the exterior member, the plurality of batteries correspond to the plurality of openings. The method for manufacturing a battery according to claim 17, wherein an element is provided, and the exterior member is cut so that each battery element is covered by the exterior member. 21. A method for manufacturing a battery in which an electrode body provided with an electrolyte together with a positive electrode and a negative electrode is covered by an exterior member, wherein: a step of forming an opening in the exterior member; Forming a conductor layer so as to cover the opening; and so that the conductor layer is electrically connected to the positive electrode or the negative electrode, the electrode body is formed by an exterior member on which the conductor layer is formed. And a covering step. 22. The method according to claim 21, wherein an electrolyte containing a polymer compound and an electrolyte salt is used as the electrolyte. 23. A film comprising a polymer compound as the exterior member.
A method for producing the battery according to the above. 24. In the step of forming an opening in the exterior member, a plurality of openings are formed apart from each other, and in the step of covering the electrode body with the exterior member, the plurality of electrodes correspond to the plurality of openings. 22. The method for manufacturing a battery according to claim 21, wherein a body is provided, and the exterior member is cut so that each electrode body is covered by the exterior member.