JP6742155B2 - Electrochemical cell - Google Patents

Description

The present invention relates to electrochemical cells.

As an electrochemical cell such as a secondary battery used as a power source of various devices or a capacitor, a configuration including an electrode body in which an electrolyte is interposed between a positive electrode layer and a negative electrode layer, and an exterior body housing the electrode body is provided. Are known.

Here, as the above-mentioned electrode body, an electrode body in which an electrolyte such as a polymer electrolyte or a solid electrolyte is interposed between a positive electrode layer and a negative electrode layer is known. As such an electrode body, for example, as shown in Patent Documents 1 and 2, the negative electrode layers 912a to 912c electrically contact with each other inside the openings penetrating the positive electrode layers 911b and 911c and the electrolyte layer 913 adjacent thereto. Also, there is known an electrode body in which the positive electrode layers 911a to 911c are in electrical contact with each other inside the opening penetrating the negative electrode layers 912b and 912c and the electrolyte layer 913 adjacent thereto (FIG. 1(a)). ..

JP, 2005-097152, A JP, 2013-243006, A

In recent years, electrochemical cells have been required to have an optimal shape in addition to being thin and lightweight, and a shape such that at least a part of the plate shape is curved. Has become required to have.

However, in the electrochemical cell disclosed in Patent Document 1, when at least a part of the electrochemical cell is curved after the plate-shaped electrochemical cell is manufactured, each layer is, for example, as shown in a partially enlarged view of FIG. Due to the difference in curvature, the arrangement of the layers forming the electrochemical cell may be displaced, and the positive electrode layers 911a to 911c and the negative electrode layers 912a to 912c may be electrically short-circuited. On the other hand, considering the curvature when bending the electrochemical cell, it is possible to provide an opening in the electrode layer or the electrolyte layer, but it is necessary to adjust the arrangement of all layers, so that the productivity is improved. There is concern about a decline. Therefore, there is still room for improvement in efficiently obtaining an electrochemical cell in which an electrical short circuit is unlikely to occur even with a curved shape.

The present invention has been made in view of such circumstances, and an object thereof is to provide an electrochemical cell in which an electrical short circuit is unlikely to occur even in a curved shape and which has high productivity. Is.

The present inventors curved the opening provided in the electrode layer and the electrolyte layer by providing the opening having a ratio of the length to the width of a predetermined value or more so as to include the curved surface of the electrochemical cell. The inventors have found that electrical shorts are reduced even in an electrochemical cell having a shape, and have completed the present invention.
Specifically, the present invention provides the following.

(1) A plate-shaped electrochemical cell having a curved shape at least in part at least during use, wherein the first electrode layer is laminated with an electrolyte layer sandwiched between both sides of the first electrode layer. A second electrode layer, and at least one first opening penetrating the first electrode layer is provided, and inside the first opening part, both sides of the first electrode layer are provided. An electrochemical cell in which the second electrode layer conducts, wherein the first opening is configured so that the length in the longitudinal direction is 1.2 times or more the width in the width direction, and at least during use. In the electrochemical cell, the first opening is formed so that at least a part thereof is curved.

(2) The electrochemical cell according to (1), wherein a short circuit prevention layer is provided so as to cover the first opening of the first electrode layer.

(3) The electrochemical cell according to (1) or (2), wherein at least a part of the first electrode layer has a curved plate shape at least during use.

(4) The electrochemical cell according to any one of (1) to (3), wherein the first opening is formed so as to be curved in the longitudinal direction at least during use.

(5) At least in use, at least a part of the surface of the first electrode layer adjacent to the electrolyte layer forms a substantially partially cylindrical surface or a substantially elliptical cylindrical surface,
The electrochemical cell according to (4), wherein the longitudinal direction of the first opening forms an angle of 45° to 135° with respect to the direction of the central axis of the substantially cylindrical or substantially elliptic cylinder.

(6) The electrochemical cell according to any one of (1) to (5), wherein the first opening is formed in a straight line.

(7) The electrochemical cell according to (6), wherein a plurality of the first openings are formed on the same straight line.

(8) The first opening is configured to include a portion having the length of 2.4 mm or more and the width of 2.0 mm or less (1) to (7). Electrochemical cell.

(9) The electrochemical cell according to any one of (1) to (8), wherein the first electrode layer contains a solid electrolyte, a polymer electrolyte, or a composite electrolyte of a solid electrolyte and a polymer electrolyte.

(10) The inner wall of the first opening is covered with a solid electrolyte, a polymer electrolyte, a composite electrolyte of a solid electrolyte and a polymer electrolyte, or an insulating material, according to any one of (1) to (9). Electrochemical cell.

(11) The electrochemical cell according to any one of (1) to (10), wherein the second electrode layers on both sides of the first opening are in contact with each other via a conductive member.

(12) At least one second opening portion is provided on both sides of the second electrode layer, the first electrode layer being laminated with the electrolyte layer interposed therebetween, and at least one second opening penetrating the second electrode layer is provided. Inside the opening, an electrochemical cell in which the first electrode layers on both sides of the second electrode layer conduct, wherein the second opening has a length in the longitudinal direction of a width in the width direction. The second opening is formed so as to include a portion that is 1.2 times or more, and the second opening is formed so that at least a part thereof is curved at least when used (1) to (11) Electrochemical cell.

(13) A plurality of the first electrode layers and a plurality of the second electrode layers are alternately laminated with the electrolyte layer interposed therebetween, the first electrode layer is provided at one end in the stacking direction, and the other end is provided at the other end. A second electrode layer is provided, the first opening is provided so as to penetrate each of the first electrode layers provided other than the one end and an electrolyte layer adjacent thereto, The electrochemical cell according to (12), wherein the opening is provided so as to penetrate each of the second electrode layers provided other than the other end and the electrolyte layer adjacent thereto.

(14) The electrochemical cell according to any one of (1) to (13), further including an exterior body that houses the electrode body.

(15) The exterior body includes a first electrode side container that covers the electrode body from one end side in the stacking direction and a second electrode side container that covers the electrode body from the other end side in the stacking direction. The electrochemical cell according to (14), wherein one electrode layer is electrically connected to the first electrode side container, and the second electrode layer is electrically connected to the second electrode side container.

(16) The electrochemical cell according to any one of (1) to (15), wherein one of the first electrode layer and the second electrode layer is a positive electrode layer and the other is a negative electrode layer.

According to the present invention, it is possible to provide an electrochemical cell in which an electrical short circuit is unlikely to occur even in a curved shape and which has high productivity.

Further, according to the present invention, even after being formed into a curved shape, conduction of each of the positive electrode layer and the negative electrode layer is maintained inside the electrode body, so that a plurality of plate-shaped electrochemical cells are stacked together. It is also possible to obtain an electrochemical cell by molding the one cut out into a curved shape. In particular, when the conduction of each of the positive electrode layer and the negative electrode layer inside the electrode body is achieved through the conductive member, it is not necessary to form a current collector on the outer periphery of the electrochemical cell. The productivity of can be improved.

Further, according to the present invention, since the multilayer structure can be easily achieved even with the curved shape, the capacity of the electrochemical cell can be further increased.

It is sectional drawing which shows the electrochemical cell which concerns on a prior art. It is a perspective view of the secondary battery which concerns on 1st embodiment. FIG. 2B is a cross-sectional view corresponding to the line I-I in FIG. 2A. FIG. 2B is a cross-sectional view corresponding to the line II-II in FIG. 2A. It is a perspective schematic diagram which shows the laminated state of FIG. 2A. FIG. 6 is a schematic plan view showing a step of cutting the electrode body array into electrode bodies. It is sectional drawing of the secondary battery which concerns on 3rd embodiment.

The electrochemical cell of the present invention is a plate-shaped electrochemical cell having a curved shape at least partially at least in use, and has a first electrode layer and an electrolyte layer sandwiched on both sides of the first electrode layer. And a second electrode layer laminated with, and at least one first opening penetrating the first electrode layer is provided, and the first electrode is provided inside the first opening. An electrochemical cell in which the second electrode layers on both sides of the layer are electrically connected, wherein the first opening has a length in the longitudinal direction of 1.2 times or more the width in the width direction. The first opening is formed so that at least a part thereof is curved at least during use.

Embodiments according to the present invention will be described below with reference to the drawings. In the following description, a secondary battery will be described as the electrochemical cell according to the present invention. In the drawings used in the following description, the scale of each member is appropriately changed in order to make each member recognizable. In addition, a description of a duplicated part may be omitted as appropriate, but the gist of the invention is not limited thereto.

The "opening" in the present invention is not limited to one having a shape that does not overlap the outer edge of the electrode layer, and may have a shape in which the electrode layer is cut from the outer edge, and the electrode layer is divided by the opening. May be.

<First embodiment>
[Secondary battery]
As shown in FIG. 2A, for example, the secondary battery 1A of the present embodiment is held by an exterior body such as a laminate member 43, and is electrically connected to the outside by tab wires 41 and 42. The exterior body is provided with an electrode body 2 as shown in FIGS. 2B and 2C, and a polymer electrolyte is used as an electrolyte used for the electrode body 2.

Here, the secondary battery 1A has a shape in which at least a part thereof is curved toward the stacking direction of the electrode bodies 2 at least when in use. That is, the shape of the secondary battery 1A may have a shape in which at least a part thereof is curved both when not in use and when used, and the secondary battery 1A has flexibility by being provided. Alternatively, it may have a flat plate shape when not in use, and may have a shape in which a part thereof is curved when in use.

(Basic configuration of electrode body)
As shown in FIGS. 2B and 2C, the electrode body 2 has a structure in which a plurality of first electrode layers 11 and second electrode layers 12 are alternately laminated on both sides with an electrolyte layer 13 interposed therebetween. In the present embodiment, the first electrode layer 11 is described as the positive electrode layer (positive electrode layer 11) and the second electrode layer 12 is described as the negative electrode layer (negative electrode layer 12). However, the first electrode layer 11 is the negative electrode layer and the second electrode. Layer 12 may be a positive electrode layer. The positive electrode layer 11 and the negative electrode layer 12 are laminated in the same number.

Here, the positive electrode layer 11 and the negative electrode layer 12 that configure the electrode body 2 are configured to have a plate shape that is curved toward the stacking direction of the electrode body 2 in at least a part thereof, as in the secondary battery 1A. Is preferred. By constructing the electrode body 2 using the curved positive electrode layer 11 and the negative electrode layer 12, the secondary battery 1A having a similar curved shape is manufactured, and thus the number of stacked layers in the secondary battery 1A is suppressed. Therefore, the production efficiency of the secondary battery 1A can be improved.

The positive electrode layer (first electrode layer) 11 includes a positive electrode current collecting layer (first electrode current collecting layer) 14 that constitutes one end (lowermost layer in FIGS. 2B and 2C) of the electrode body 2 in the stacking direction, and an electrolyte layer. And a positive electrode connection layer (first electrode connection layer) 15 arranged between the electrodes 13. Among them, in the positive electrode connecting layer 15, first opening portions 16 penetrating the positive electrode connecting layer 15 in the stacking direction are formed at intervals in the in-plane direction orthogonal to the stacking direction.

The negative electrode layer (second electrode layer) 12 includes the negative electrode current collecting layer (second electrode current collecting layer) 22 that constitutes the other end (the uppermost layer in FIGS. 2B and 2C) of the electrode body 2 in the stacking direction, and The positive electrode connecting layer (first electrode connecting layer) 15 and the negative electrode connecting layer (second electrode connecting layer) 23 stacked on both sides in the stacking direction with the electrolyte layer 13 interposed therebetween. In the negative electrode connection layer 23, the second openings 26 that penetrate the negative electrode connection layer 23 in the stacking direction are formed at intervals in the in-plane direction described above.

The positive electrode layer 11 and the negative electrode layer 12 may include a metal base material such as an aluminum foil or a copper foil. As a result, the morphological stability of the positive electrode layer 11 and the negative electrode layer 12 is enhanced, and thus it is possible to easily form a desired curved shape during use.

In the present embodiment, the first opening 16 and the second opening 26 formed in the positive electrode connecting layer 15 and the negative electrode connecting layer 23 are, as shown in FIG. 2D, opening portions of the connecting layers 15 and 23 of different polarities. Is formed at a position that does not overlap with the stacking direction.

The electrolyte layer 13 is interposed between the positive electrode layer 11 and the negative electrode layer 12 to separate the positive electrode layer 11 and the negative electrode layer 12 from each other.

(First and second openings)
Here, the first opening 16 is provided so as to penetrate the positive electrode layer (first electrode layer) 11, and the second opening 26 is provided so as to penetrate the negative electrode layer (second electrode layer) 12.

The first opening portion 16 and the second opening portion 26 are formed so that at least a part thereof is curved at the time of use.

Here, it is preferable that the first opening 16 and the second opening 26 are formed such that the longitudinal direction thereof is curved toward the stacking direction of the electrode bodies 2 at least when in use. Thereby, since the first opening 16 and the second opening 26 have a length in the direction crossing the curved surface, the electrode body 2 is curved and the arrangement of the positive electrode layer 11, the negative electrode layer 12, and the electrolyte layer 13 is displaced. Even in this case, the conduction of the positive electrode layer 11 and the negative electrode layer 12 in the stacking direction is maintained, and the conduction of the positive electrode layer 11 and the negative electrode layer 12 becomes more difficult to occur, so that the reduction of the battery capacity due to the bending of the electrode body 2 is suppressed. be able to.

For example, at least a part of the surface of the positive electrode layer 11 or the negative electrode layer 12 adjacent to the electrolyte layer 13 forms a curved surface at least during use, and the curved surface forms a substantially partially cylindrical surface or a substantially partially elliptical cylindrical surface. In this case, the longitudinal direction of the first opening 16 and the second opening 26 in the plan view of the positive electrode layer 11 and the negative electrode layer 12 is 45° with respect to the direction of the central axis of the substantially columnar or elliptical column. It is preferable to form an angle of ˜135°, more preferable to form an angle of 70° to 110°, and most preferable to form a substantially right angle. By constructing the longitudinal direction of the first opening 16 and the second opening 26 in a direction close to a right angle with respect to the central axis of the substantially columnar shape or the substantially elliptic cylinder, the electrode body 2 is curved and the positive electrode layer is formed. When the positions of 11, the negative electrode layer 12, and the electrolyte layer 13 are deviated, the direction in which they are displaced and the longitudinal direction of the first opening 16 and the second opening 26 are close to each other. The conduction of the negative electrode layer 12 can be easily maintained.

The first opening 16 and the second opening 26 are preferably formed so as to be linear in a plan view of the positive electrode layer 11 and the negative electrode layer 12. As a result, the first opening 16 and the second opening 26 can be formed more densely, so that the internal resistance of the secondary battery 1A can be further reduced. On the other hand, the first opening 16 and the second opening 26 may be formed so as to have a curved shape in a plan view of the positive electrode layer 11 and the negative electrode layer 12. Thereby, even if the arrangement of the positive electrode layer 11, the negative electrode layer 12, and the electrolyte layer 13 is deviated in a direction other than the longitudinal direction, it is possible to easily maintain the conduction of the positive electrode layer 11 and the negative electrode layer 12 in the stacking direction.

The length in the longitudinal direction of the first opening 16 and the second opening 26 is formed to be 1.2 times or more the width in the width direction perpendicular to the longitudinal direction. Accordingly, even if the electrode body 2 is curved and the arrangement of the positive electrode layer 11, the negative electrode layer 12, and the electrolyte layer 13 is deviated, it is easy to maintain conduction between the positive electrode layer 11 and the negative electrode layer 12 in the stacking direction. It is possible to suppress a decrease in battery capacity due to the body 2 having a curved shape. Here, the ratio of the length in the longitudinal direction 1 to the width in the width direction is preferably 1.2 times or more, more preferably 2.0 times or more, and further preferably 5.0 times or more.

Here, the first opening 16 and the second opening 26 include a portion having a length in the longitudinal direction of preferably 2.4 mm or more, more preferably 3.0 mm or more, and further preferably 5.0 mm or more. To configure. At this time, the width in the width direction is preferably 2.0 mm or less, more preferably 1.5 mm or less, and further preferably 1.0 mm or less. By forming the opening having such a size, even if the arrangement of the positive electrode layer 11, the negative electrode layer 12, and the electrolyte layer 13 is deviated, it is possible to easily maintain the conduction of the positive electrode layer 11 and the negative electrode layer 12 in the stacking direction. ..

The “longitudinal direction” of the first opening 16 and the second opening 26 in this specification is the longitudinal direction of the positive electrode layer 11 and the negative electrode layer 12 in plan view. The “width direction” of the first opening 16 and the second opening 26 is a direction orthogonal to the longitudinal direction in a plan view of the positive electrode layer 11 and the negative electrode layer 12.

The shapes of the first opening 16 and the second opening 26 in plan view are not particularly limited as long as they have the sizes in the longitudinal direction and the width direction described above, but the first opening 16 and the second opening 26 are formed. From the viewpoint of making it easy, it is preferable that the shape is, for example, a rectangle or an ellipse.

The first opening 16 and the second opening 26 may be formed on the same straight line in plan view of the positive electrode layer 11 and the negative electrode layer 12, but one line from one end face to the other end face. It is preferable that they are continuously formed into a shape.
Particularly, by forming the first opening portion 16 and the second opening portion 26 continuously in one linear form from one end surface to the other end surface, the short circuit is more reliable even at the end surface where the short circuit is likely to occur. Can be prevented.
On the other hand, by forming a plurality of first openings 16 and second openings 26 on the same straight line or curved line, the first opening 16 and the second opening 26 are formed in the electrode body 2 in the direction along the center line. Since the positive electrode layer 11 and the negative electrode layer 12 in which the two openings 26 are formed are connected in the plane, an increase in the internal resistance of the electrode body 2 can be suppressed.

Short-circuit preventing layers 17 and 27 are provided inside the first opening 16 and the second opening 26 so as to cover the wall surfaces thereof. By covering the inner wall of the first opening 16 with the short-circuit prevention layer 13, conduction between the positive electrode layer 11 and the negative electrode layer 12 via the inner wall of the first opening 16 can be suppressed.

The insides of the first opening 16 and the second opening 26 covered with the short-circuit prevention layers 17 and 27 are on both sides of the electrode layer in which the first opening 16 and the second opening 26 are provided. The electrode layers are configured to be conductive. More specifically, the negative electrode layers 12 on both sides of the positive electrode layer 11 are configured to conduct inside the first opening 16, and the positive electrode layers 11 on both sides of the negative electrode layer 12 inside the second opening 26. Are configured to conduct.

At this time, the negative electrode layers 12 on both sides of the positive electrode layer 11 may be electrically connected via the conductive member 31 or may be in direct contact without the conductive member 31. Further, the positive electrode layers 11 on both sides of the negative electrode layer 12 may be electrically connected via the conductive member 32, or may be in direct contact without the conductive member 32. In particular, by electrically connecting the positive electrode layer 11 and the negative electrode layer 12 through the conductive members 31 and 32, the electrode layers on both sides of the opening can be formed even if the positive electrode layer 11 and the negative electrode layer 12 do not greatly enter the opening. Because of conduction, even when the electrode body 2 has a curved shape, conduction in the stacking direction of the electrode layers can be easily obtained, and the internal resistance of the secondary battery 1A can be reduced.

(Constituent material of the electrode body)
The positive electrode layer 11 that constitutes the electrode body 2 contains a positive electrode active material, a conductive auxiliary agent, an electrolyte, and the like. Further, the negative electrode layer 12 contains a negative electrode active material, a conductive auxiliary agent, an electrolyte and the like. Moreover, the electrolyte layer 13 and the short-circuit prevention layers 17 and 27 contain an electrolyte. When the conductive member 31 is provided, the conductive member 31 contains a conductive auxiliary agent, a positive electrode active material or a negative electrode active material, an electrolyte, a binder and the like.

Here, the positive electrode layer 11 and the negative electrode layer 12 may be partially formed of a metal plate in the stacking direction from the viewpoint of easily maintaining a curved shape. An example of the metal plate forming a part of the positive electrode layer 11 is an aluminum plate, and an example of a metal plate forming a part of the negative electrode layer 12 is a copper plate. In particular, in the configuration in which the gel electrolyte is used for the positive electrode layer 11 and the negative electrode layer 12, the metal plate forming the positive electrode layer 11 and the negative electrode layer 12 may be a porous body in order to improve the impregnation efficiency of the electrolytic solution into the matrix polymer.

The short circuit prevention layers 17 and 27 may be made of an electrolyte or an insulating material.

The thickness of the short circuit prevention layers 17 and 27 is preferably 0.1 mm or more, more preferably 0.3 mm or more, and further preferably 0.5 mm or more. Thereby, even if the arrangement of the positive electrode layer 11, the negative electrode layer 12, and the electrolyte layer 13 is deviated, a short circuit between the positive electrode layer 11 and the negative electrode layer 12 can be reduced.

Here, the positive electrode active material is preferably a layered oxide or a spinel type oxide. Among them, particularly, LiMtO ₂ and/or LiMt ₂ O ₄ (however, Mt is one or more selected from Fe, Ni, Co and Mn), NASICON type LiV ₂ (PO ₄ ) ₃ and olivine type Li. _x MtPO ₄ (where Mt is at least one selected from Ni, Co, Fe and Mn) is more preferable. This makes it easier for the positive electrode active material to occlude lithium ions, so that the discharge capacity of the secondary battery 1A can be further increased. As specific examples of the positive electrode active material, LiCoO ₂ , LiNiO ₂ , NCA, NMC, LiMn ₂ O ₄ , LiNi _0.5 Mn _1.5 O ₄ , LiFePO ₄ , LiMnPO ₄ , and LiCoPO ₄ can be used.

As the negative electrode active material, in addition to carbon-based materials, oxides including NASICON-type, olivine-type, and spinel-type crystals, rutile-type oxides, anatase-type oxides, amorphous metal oxides, metal alloys, and the like are used. At least one selected from the above is preferable. Among them, graphite, hard carbon, SiOx (0.25≦x≦2), Si, Li ₄ Ti ₅ O ₁₂ and TiO ₂ are particularly preferable. This makes it easier for the negative electrode active material to occlude lithium ions, so that the discharge capacity of the secondary battery 1A can be further increased.

As the conductive additive, carbon, a metal composed of at least one of Ni, Fe, Mn, Co, Mo, Cr, Ag and Cu, and alloys thereof can be used. Alternatively, a metal such as titanium, stainless steel, or aluminum, or a noble metal such as platinum, silver, gold, or rhodium may be used. By using such a material having a high electron conductivity as a conduction aid, the amount of current that can be conducted through a narrow electron conduction path formed in the positive electrode layer 11 increases, so that internal resistance can be obtained without using a current collector. A secondary battery 1A having a small size can be formed. Among these, it is preferable to use a carbon-based conductive auxiliary agent such as acetylene black (AB) having a small specific gravity. As a result, the weight energy density can be easily increased, and the internal resistance can be easily reduced. On the other hand, when a metal or an alloy is used as the conduction aid, it is preferable to use Al powder as the conduction aid on the positive electrode side and Cu powder as the conduction aid on the negative electrode side.

A polymer electrolyte is preferably used as the electrolyte. By forming the electrolyte from these substances, the polymer electrolyte and the electrode layer have flexibility, and damage to the positive electrode layer 11, the negative electrode layer 12, and the electrolyte layer 13 due to pressing during the production of the electrode body 2 is reduced. Therefore, the increase in internal resistance can be suppressed.

Here, as the polymer electrolyte, a dry polymer electrolyte obtained by adding a lithium supporting salt to a host polymer such as polyethylene oxide, a gel polymer electrolyte containing an electrolyte solution in a matrix polymer such as polyvinylidene fluoride, and methyl methacrylate, etc. Any of the ionic gel electrolytes obtained by adding an ionic liquid such as EMITFSI to the vinyl monomer in situ and polymerized in situ can be used, but the ionic conductivity is high in the practical temperature range (-20°C to 60°C) and the oxidation resistance The gel-based polymer electrolyte is particularly preferable because it has good properties.

As the matrix polymer of the gel polymer electrolyte, polyethylene oxide, polymethyl methacrylate, polyvinyl alcohol, polyacrylonitrile, polyacrylamide, polysulfone, polyamide, polyimide, polyvinylidene chloride, polyvinylidene fluoride, polyvinylidene fluoride-hexafluoropropylene copolymer, Polyvinylidene fluoride-chlorotrifluoroethylene copolymer, polyvinylidene fluoride-perfluoroethylene copolymer, polyvinylidene fluoride-trifluoroethylene copolymer, polyvinylidene fluoride-fluoroethylene copolymer, polyvinylidene fluoride-propylene copolymer, derivatives thereof, and further these A copolymer, a mixture and the like can be used. In particular, polyvinylidene fluoride and polyvinylidene fluoride-hexafluoropropylene copolymer, polyvinylidene fluoride-chlorotrifluoroethylene copolymer is thermoplastic, further, because it can be pressure-bonded at a temperature that does not deteriorate the constituent materials such as the electrode layer, The electrode layer can be satisfactorily pressure-bonded. Further, these materials can be handled in the state before the gelation without containing the electrolytic solution during the step of producing the electrode body 2, and the gelling step can be performed after the production of the electrode body 2. The electrode body 2 is easy to manufacture. Further, by adding dibutyl phthalate, which is a plasticizer, at the time of making the sheet, and after making the electrode body 2, it is possible to make the matrix polymer have a porous structure by extracting with a nonpolar organic solvent such as diethyl ether or tetrahydrofuran. It is possible to improve the liquid retention rate and the ionic conductivity.

As the electrolytic solution, ethylene carbonate, propylene carbonate, dimethyl carbonate, vinylene carbonate, butylene carbonate, chloroethylene carbonate, ethyl methyl carbonate, diethyl carbonate, ethyl-n-butyl carbonate, methyl-t-butyl carbonate, di-i-propyl carbonate. Carbonates, carbonates such as t-butyl-i-propyl carbonate, γ-butyrolactone, γ-valerolactone, esters such as methyl formate, methyl acetate, ethyl acetate, ethyl butyrate, dimethoxyethane, ethoxymethoxymethane, diethoxyethane. ethers etc., nitriles such as acetonitrile and benzonitrile, tetrahydrofuran, LiPF furans such as methyl tetrahydrofuran, sulfolane, sulfolane such as tetra Mechie Rusuru Holland, in an organic solvent such as dioxolanes such as 1,3-dioxolane _{6 , LiBF 4, LiAsF 6, LiSbF} 6, LiSiF 6, LiAlF 4, LiSCN, LiCl, LiClO 4, LiF, LiBr, LiI, LiAlCl 4, LiCF 3 SO 3, LiTFSI, lithium ions dissolved lithium supporting salt such as LiBETI Electrolytes commonly used in batteries can be used, but the materials for the electrolyte are not limited to these.

In addition, gel-type polymer electrolytes include ceramics such as silica, alumina and barium titanate for the purpose of suppressing the fluidity of gel at high temperature and improving strength, and glass with lithium ion conductivity, glass ceramics, and inorganics of ceramics. Fine particles may be added.

As the conductive member, the same constituent material as the electrode, that is, an electrode active material and a conductive auxiliary agent, may be configured by using a polymer electrolyte, a conductive auxiliary agent and a polymer electrolyte, a conductive auxiliary agent, or a conductive auxiliary agent and a binder. It may be configured by using. In particular, when a carbonaceous material such as acetylene black is used as the conductive additive and no electrode active material is contained, it can be used as either the positive electrode side or the negative electrode side conductive member. As described above, by using the conductive member, the strain on the electrode layers due to the direct contact between the electrode layers can be reduced.

In the present embodiment, the first electrode layer 16 or the second electrode layer 26 may be directly contacted with each other without using the conductive member.

(Exterior body)
Various modes can be used as the mode of the exterior body for protecting the electrode body 2 from contact with the outside air and unintended conduction with the outside of the battery.
For example, as shown in FIGS. 2B and 2C, it is preferable that the electrode body 2 is vacuum-packed by laminating members 43 and 44 such as aluminum laminate. As a result, contact between the electrode body 2 and the outside air is reduced, so that the secondary battery 1A that can withstand long-term use can be obtained. In addition, when the electrode body 2 has flexibility in shape, the entire shape of the secondary battery 1A can be made flexible.

More specifically, as shown in FIGS. 2B and 2C, the positive electrode collector layer 14 of the electrode body 2 and the tab wire 41 are in contact with each other so as to be electrically connected. Further, the negative electrode current collecting layer 22 of the electrode body 2 and the tab wire 42 are in contact with each other so as to be electrically connected.

[Preparation of secondary battery]
Next, a method for manufacturing the above-described secondary battery 1A will be described.
The method for producing the secondary battery 1A according to the present embodiment includes a positive electrode sheet producing step of applying the raw material composition of the positive electrode layer 11 and the electrolyte layer 13 to a metal plate on which an opening serving as a base of the first opening 16 is formed. A negative electrode sheet producing step of applying the raw material composition of the negative electrode layer 12 and the electrolyte layer 13 to a metal plate having an opening which is a base of the second opening 26, and the positive electrode sheet producing step and the negative electrode sheet producing step. The method includes a laminating step of laminating the produced positive electrode sheet and negative electrode sheet, and a hot pressing step of heating while heating the laminated body of the positive electrode sheet and the negative electrode sheet.

Here, as a laminate of the positive electrode sheet and the negative electrode sheet, a product having a size in which a plurality of them are collected is subjected to a hot pressing process, and the obtained array of electrode bodies 2 (electrode body array 3) is formed into the electrode body 2. You may cut each. Thereby, the positive electrode sheet and the negative electrode sheet can be efficiently laminated, so that the productivity of the secondary battery 1A can be further improved.

(Raw material composition)
The raw material composition used for producing the secondary battery contains an electrolyte such as a polymer electrolyte, an electrode active material and a conductive auxiliary agent, and is in the form of a slurry or a paste. Thereby, since the raw material composition has a desired viscosity and hardness, the positive electrode layer 11, the negative electrode layer 12, and the electrolyte layer 13 are produced by using such a raw material composition, so that the first opening portion 16 and the first opening portion 16 The electrode layers separated by the two openings 26 can be easily conducted.

The raw material composition of the positive electrode layer 11 preferably contains a solvent for facilitating coating, in addition to the electrolyte, the electrode active material, and the conductive additive described above. Here, as the solvent, known materials such as acetone, NMP, DMF, DMAc, PVA, 1-propanol, IPA and butanol can be used. In addition, a plasticizer such as dibutyl phthalate (DBP) may be used to facilitate coating, and an appropriate amount of a dispersant may be used in combination to obtain a more homogeneous and dense polymer electrolyte or electrode layer. Alternatively, an appropriate amount of surfactant may be used in combination in order to improve the defoaming efficiency during drying.

(Cathode sheet manufacturing process)
In the positive electrode sheet preparation step, the raw material composition of the positive electrode layer 11 is applied to a metal base material (aluminum foil) having an opening serving as a base of the first opening 16 to form a positive electrode sheet.

Here, as the means for forming the opening that becomes the base of the first opening 16 in the base material, for example, means such as laser irradiation or punching can be used.

The coating of the raw material composition is performed on both sides of the base material for the positive electrode sheet to be the positive electrode connecting layer 15, and to one side of the base material for the positive electrode sheet to be the positive electrode current collecting layer 14. As a result, the metal base material is exposed on one surface of the positive electrode current collector layer 14, so that it is not necessary to provide a current collector separately from the electrode body 2 to be manufactured.

Examples of the means for applying the raw material composition include a raw material composition for the negative electrode layer 12 and the electrolyte layer 13, which will be described later, for example, a doctor blade, a calendar method, a coating method such as spin coating or dip coating, a printing method, a die coater method, A spray method can be used.

In the formed positive electrode sheet, an opening is formed in a portion where the first opening 16 is formed. As a means for forming the opening in the positive electrode sheet, for example, a means such as laser irradiation can be used.

Next, the raw material composition of the electrolyte layer 13 is applied to the positive electrode sheet. At this time, it is preferable that screen printing be performed on the positive electrode green sheet to apply the raw material composition of the electrolyte layer 13. As a result, the applied raw material of the electrolyte layer 13 can be handled integrally with the metal base material, so that the electrolyte layer 13 can be made thinner and the discharge capacity per unit volume of the secondary battery can be increased. At this time, the short-circuit prevention layer 27 may be provided using an electrolyte or an insulating material separately from the electrolyte layer 13, but from the viewpoint of further reducing the internal resistance of the secondary battery and the number of steps, the electrolyte layer It is preferable to provide the short-circuit prevention layer 27 by wrapping the raw material composition of No. 13 inside the first opening 16.

An opening is formed in the electrolyte layer 13 in a region adjacent to the second opening 26 in the positive electrode sheet on which the electrolyte layer 13 is formed. As the means for forming the opening, for example, means such as laser irradiation can be used. Here, the opening formed in the electrolyte layer 13 may be penetrated from the viewpoint of facilitating conduction when the conductive member 31 described later is used, but the positive electrode layer 11 is bent to adjoin the adjacent positive electrode layer 11. From the viewpoint of contacting with, the depth may be such that the raw material composition of the positive electrode layer 11 is exposed.

The conductive member 31 may be formed inside the first opening 16 provided with the short-circuit prevention layer 17 and in the opening formed in the electrolyte layer 13. The conductive member 31 may be made of the same constituent material as the electrode, or may be made of a combination of a conductive auxiliary agent and a polymer electrolyte, a conductive auxiliary agent, or a conductive auxiliary agent and a binder.

(Negative electrode sheet manufacturing process)
In the negative electrode sheet manufacturing process, the raw material composition of the negative electrode layer 12 is applied onto a metal base material (copper foil) having an opening to be the base of the second opening 26 to form a negative electrode sheet. In the negative electrode sheet producing step, the negative electrode sheet can be produced by the same means as in the positive electrode sheet producing step.

(Lamination process)
In the laminating step, the positive electrode sheet and the positive electrode sheet are arranged such that the portions of the positive electrode layer 11 corresponding to the first openings 16 overlap in the laminating direction and the portions of the negative electrode layer 12 corresponding to the second openings 26 overlap in the laminating direction. Negative electrode sheets are alternately laminated to produce a sheet laminate. As a result, the opening of the positive electrode sheet and the region of the negative electrode sheet to which the raw material composition of the electrolyte layer 13 is not applied are continuous, and the opening of the negative electrode sheet and the raw material composition of the electrolyte layer 13 of the positive electrode sheet. Since the region where is not applied is continuous, the electrode layer and the electrolyte layer 13 adjacent to the electrode layer can be penetrated particularly when the conductive member 31 is not used.

As a specific mode of the laminating step, for example, a mode in which the step of laminating the positive electrode sheet and the negative electrode sheet is repeatedly performed until a predetermined number of layers is laminated, and then a predetermined press pressure is applied can be mentioned. At this stage, since the sheets are not bonded to each other, the laminated body can be curved.

(Drying process)
Then, the solvent contained in the sheet laminate is heated to evaporate the solvent and remove the solvent. By this step, the solvent contained in the laminated body after the hot pressing is reduced, so that it is possible to easily remove the bubbles from the laminated body.
The drying step may be performed at the same time as the application of each sheet, may be performed on each coated sheet, or may be performed on the sheet laminate after the laminating step.
The lower limit of the heating temperature in the drying step is preferably 20°C, more preferably 30°C, and further preferably 40°C from the viewpoint of easily evaporating the solvent. On the other hand, particularly when a polymer electrolyte is used, from the viewpoint of reducing thermal decomposition, the upper limit is preferably 300° C., more preferably 200° C., and further preferably 150° C.

(Heat press process)
In the hot pressing step, the sheet laminated body is sandwiched between jigs and heated while being pressed in the laminating direction. In particular, when the plate-shaped electrode body 2 having at least a part of a curved shape is manufactured, the sheet laminated body is sandwiched by a jig having a curved surface and heated while being pressed in the laminating direction. As a result, in the laminate, the positive electrode sheets adjacent to each other with the negative electrode sheet interposed therebetween are electrically connected in the stacking direction through the second opening 26 of the negative electrode layer 12. On the other hand, in the laminated body, the adjacent negative electrode sheets sandwiching the positive electrode sheet are electrically connected to each other in the laminating direction through the first opening 16 of the positive electrode layer 11.

The lower limit of the pressure for pressing the sheet laminate in the pressing step is preferably 0.01 MPa, more preferably 0.05 MPa, and most preferably 0.1 MPa from the viewpoint of easily obtaining such effects. Further, the upper limit of this pressure is preferably 200 MPa, more preferably 100 MPa, and most preferably 10 MPa from the viewpoint of reducing damage to the molding die and the sheet laminate. The pressure of the sheet laminated body can be performed, for example, by placing an upper die on a molding die for molding the sheet laminated body and applying pressure with a hydraulic press or the like.
In addition, from the viewpoint of further reducing the damage to the sheet laminated body, the pressure applied to the sheet laminated body may be divided into a plurality of times.

The pressing temperature is preferably adjusted to a temperature at which the polymer electrolyte melts and the electrode layer and the electrolyte layer are welded together, from the viewpoint that the resistance of the entire battery can be reduced. From the viewpoint of easily obtaining such effects, the lower limit is preferably 40°C, more preferably 60°C, and most preferably 80°C. Moreover, the upper limit of the pressing temperature is preferably 300° C., more preferably 250° C., and further preferably 200° C. from the viewpoint that the polymer electrolyte is completely melted and the contact between the positive electrode layer and the negative electrode layer is prevented.

If necessary, an additive such as a plasticizer is extracted from the electrode body 2 after the hot pressing step using a solvent such as diethyl ether and vacuum dried, and then the electrolyte layer 13 and the electrode layer 11 are formed. , 12 to increase the contactability with the polymer secondary battery and reduce the internal resistance of the polymer secondary battery, the host polymer may be impregnated with an organic electrolyte solution.

Here, when a stack of a plurality of positive electrode sheets and negative electrode sheets is manufactured, the obtained electrode assembly 3 is cut into individual electrode assemblies 2. At this time, as shown in FIG. 3, the positive electrode current collector layer 14 is traversed inside the opening K serving as the base of the first opening 16 and the opening (not shown) serving as the base of the second opening 26. It is preferable to cut the electrode body array 3 as described above, and for example, it is preferable to cut along the line C1-C2 in FIG. As a result, the first opening 16 and the second opening 26 are continuously formed in a linear form from one end surface to the other end surface, so that a short circuit is more likely to occur even on an end surface where a short circuit is likely to occur. It can be surely prevented.

(Set process)
The obtained electrode body 2 is set on the exterior body including the laminate members 43 and 44. More specifically, the tab wire 41 is arranged on the negative electrode side of the electrode body 2, and the tab wire 42 is arranged on the positive electrode side thereof, and the tab wires 41 and 42 are not formed on the surface of the electrode body 2 as necessary. A coating for preventing a short circuit made of a polymer electrolyte or the like is formed so as to cover the portion, and the laminate is sandwiched between the laminated members 43 and 44 to form a vacuum pack, whereby the secondary battery 1A is manufactured.

<Second embodiment>
The secondary battery of this embodiment is a so-called all-solid-state electrode body, and contains a solid electrolyte as the electrolyte contained in the electrolyte layer. Here, as the electrolyte contained in the electrolyte layer, only a solid electrolyte may be contained, or a solid electrolyte and a polymer electrolyte may be contained to form a composite electrolyte.

The secondary battery has a shape in which at least a part thereof is curved in the stacking direction of the electrode bodies both when not in use and when in use, and the shape is substantially fixed. That is, the secondary battery has a shape in which at least a part thereof is curved both when not in use and when in use.

Similar to the first embodiment, the electrode body has a plurality of positive electrode layers (first electrode layers) 11 and negative electrode layers (second electrode layers) 12 with electrolyte layers 13 on both sides, as shown in FIGS. 2B and 2C. It has a structure in which it is sandwiched and alternately laminated.

Here, as the solid electrolyte contained in the electrolyte layer 13, lithium ion conductive glass or crystal is preferably used. By forming the electrolyte from these substances, it is possible to obtain the electrode body 2 having lithium ion conductivity and high shape stability even when at least a part thereof is formed into a curved shape.

Examples of the lithium ion conductive crystal include an oxide crystal selected from NASICON type, β-Fe ₂ (SO ₄ ) ₃ type and perovskite type. More _{specifically, Li 6 BaLa 2 Ta 2 O} 12 _{and, LiN, La 0.55 Li 0.35 TiO} 3, Li 1 + X Al x (Ti, Ge) 2-X (PO 4) 3, LiTi _{2 P 3 O 12, Li 1.5} Al 0.5 Ge 1.5 (PO 4) 3, Li 1 + x + y Zr 2-x (Al, Y) x Si y P 3-y O 12 ( where 0.05 ≦x≦0.3, 0.05≦y≦0.3). Among them, Li _1+x+z E _y G _2-j Si _z P _3-y O ₁₂ (where j, x, y, and z are 0≦x≦0.8, 0≦z≦0.6, and y is 0). ≦y≦0.6, j satisfies 0≦j≦0.6, E is at least one selected from Al, Ga, Y, Sc, Ge, Mg, Ca, Ce, and Sm, and G is Ti and Zr. One or more kinds selected from) are preferred.

As the lithium ion conductive glass, for example _{LiPO 3, 70LiPO 3 -30Li 3 PO} 4, Li 2 O-SiO 2, Li 2 O-SiO 2 -P 2 O 5 -B 2 O 5 -BaO -based, non Crystalline or polycrystalline glass may be mentioned. Among them, Li ₂ O—P ₂ O ₅ based glass and Li ₂ O—P ₂ O ₅ —M′ ₂ O ₃ based glass (including those in which P is replaced by Si. M′ is Al or B). It is preferable that one or more kinds selected from

[Preparation of secondary battery]
Next, a method for manufacturing a secondary battery according to another embodiment of the present invention will be described.
In the method for manufacturing the secondary battery according to the present embodiment, after the raw material composition for the positive electrode layer 11 is applied to form the positive electrode green sheet, an opening is formed in a portion where the first opening 16 is formed, and the electrolyte layer 13 is formed. And the step of forming the negative electrode green sheet by forming the negative electrode green sheet by applying the raw material composition of the negative electrode layer 12, and then forming an opening at the portion where the second opening 26 is formed to form the electrolyte layer. A negative electrode sheet producing step of applying the raw material composition of 13; a laminating step of laminating the positive electrode sheet and the negative electrode sheet produced in the positive electrode sheet producing step and the negative electrode sheet producing step; and a laminate of the positive electrode sheet and the negative electrode sheet, A hot pressing step of heating while pressing using a jig having a curved surface.

The "green sheet" in the present invention refers to an unfired body of glass powder or crystal (ceramics or glass ceramics) powder formed into a thin plate shape. Specifically, it refers to a thin plate-shaped raw material composition composed of a solid electrolyte, an organic binder, a solvent and the like. The “green sheet” also includes another green sheet or a fired body of another green sheet coated with the raw material composition.

(Raw material composition)
The raw material composition used for producing the secondary battery contains a solid electrolyte, an electrode active material and a conductive auxiliary agent, and is in the form of a slurry or a paste.

An organic binder may be used in the raw material composition. As the organic binder, a commercially available binder generally used as a molding aid for press molding, rubber pressing, extrusion molding, and injection molding can be used. Specific examples thereof include acrylic resin, ethyl cellulose, polyvinyl butyral, methacrylic resin, urethane resin, butyl methacrylate and vinyl-based copolymers.

(Cathode sheet manufacturing process)
In the positive electrode sheet preparation step, the raw material composition of the positive electrode layer 11 is applied to form a positive electrode green sheet, and then an opening is formed in a portion where the first opening 16 is formed, and the raw material composition of the electrolyte layer 13 is applied. To do. Here, the coating of the raw material composition of the positive electrode layer 11 is preferably performed on a base material such as PET that has been subjected to a mold release treatment, but like the first embodiment, it becomes the base of the first opening 16. You may apply to the metal plate in which the opening part was formed.

An opening is formed in a portion of the manufactured positive electrode green sheet where the first opening 16 is formed. As a means for forming the opening in the positive electrode green sheet, means such as laser irradiation can be used.

Next, the raw material composition of the electrolyte layer 13 is applied to the positive electrode green sheet except for the region to be the second opening 26. At this time, it is preferable that screen printing be performed on the positive electrode green sheet to apply the raw material composition of the electrolyte layer 13. As a result, the green sheet of the electrolyte layer 13 and the positive electrode green sheet can be handled integrally, so that the electrolyte layer 13 can be made thinner and the discharge capacity per unit volume of the secondary battery can be increased. At this time, the short-circuit prevention layer 27 may be provided by using an electrolyte or an insulating material separately from the electrolyte layer 13, but from the viewpoint of reducing internal resistance and the number of steps, the raw material composition of the electrolyte layer 13 is used. It is preferable to provide the short-circuit prevention layer 27 by wrapping around the inside of the first opening 16.

Here, the conductive member 31 may be formed inside the first opening 16 provided with the short-circuit prevention layer 17, as in the first embodiment.

(Negative electrode sheet manufacturing process)
In the negative electrode sheet preparation step, the raw material composition of the negative electrode layer 12 is applied to form a negative electrode green sheet, and then an opening is formed in a portion where the second opening 26 is formed, and the raw material composition of the electrolyte layer 13 is applied. To do. In the negative electrode sheet producing step, the negative electrode sheet can be produced by the same means as in the positive electrode sheet producing step.

(Lamination process)
In the laminating step, the positive electrode sheet and the negative electrode sheet are arranged so that the portions of the positive electrode sheet corresponding to the first openings 16 overlap in the laminating direction, and the portions of the negative electrode sheet corresponding to the second openings 26 overlap in the laminating direction. Are alternately laminated to produce a sheet laminate.

As a specific mode of the laminating step, for example, after laminating a negative electrode sheet on a positive electrode sheet formed on a base material, peeling the base material of the laminated negative electrode sheet, and then peeling the base material, the negative electrode sheet After laminating the positive electrode sheet on the substrate, the step of peeling the base material of the laminated positive electrode sheet is repeated until a predetermined number of layers are laminated.

(Drying process)
Next, the solvent and the organic binder component contained in the sheet laminate are heated to evaporate and remove the solvent and the organic binder component. In particular, when an organic binder component is included, by performing a drying step at 350° C. to 550° C., carbon remaining in the solid electrolyte layer 12 after hot pressing can be reduced, so that electron conduction in the electrolyte layer 13 can be prevented.

(Heat press process)
In the hot pressing step, the sheet laminated body is sandwiched by a jig having a curved surface, and the sheet laminated body is heated while being pressed in the laminating direction, thereby manufacturing the plate-like electrode body 2 having a curved shape at least in part. This causes the negative electrode sheet to enter the inside of the first opening 16 of the positive electrode sheet due to, for example, softening of components contained in the electrolyte layer 13 and the electrode layer. It conducts through the opening 16. Further, since the positive electrode sheet enters the inside of the second opening portion 26 of the negative electrode sheet, the positive electrode sheets adjacent to each other with the negative electrode sheet interposed therebetween are electrically connected through the second opening portion 26.

In the present embodiment, particularly when the hot pressing step is performed, the positive electrode sheet and the negative electrode sheet are likely to be plastically deformed by heat and pressure, so that at least a part of the electrode body 2 having a curved shape in the laminating direction is formed. Obtainable.

The heat treatment temperature in the hot pressing step of the present embodiment is higher than the glass transition point of the lithium ion conductive glass, particularly when the raw material composition of the negative electrode green sheet or the electrolyte layer 13 contains the lithium ion conductive glass. It is preferably carried out at a temperature, more preferably 100° C. or more higher than the glass transition point of the lithium ion conductive glass. As a result, the solid electrolyte is softened to provide flexibility to the negative electrode green sheet, so that the electrode body 2 can be easily formed into a desired shape. When the green sheet of the electrolyte layer 13 contains lithium ion conductive glass, the solid electrolyte is softened to make the electrolyte layer 13 more dense. It is possible to further reduce short circuits between the two.

The maximum temperature in the hot pressing step of this embodiment is preferably set within a range in which the solid electrolyte, the electrode active material, and the conductive additive do not melt or undergo a phase change. For example, this maximum temperature may have an upper limit of preferably 1100°C, more preferably 1050°C, most preferably 1000°C.

In the hot pressing step of the present embodiment, the lower limit of the pressure for pressing the green sheet laminate is preferably 10 MPa, more preferably 50 MPa, and most preferably 100 MPa from the viewpoint of easily obtaining such an effect. .. On the other hand, the upper limit of this pressure is preferably 300 MPa, more preferably 250 MPa, and most preferably 200 MPa from the viewpoint of reducing damage to the laminate of the molding die and the green sheet. The pressurization of the green sheet laminate can be performed, for example, by placing an upper die on a molding die for forming the green sheet laminate and applying pressure with a hydraulic press or the like.

(Set process)
The obtained electrode body 2 can be set in a known exterior body including the laminate members 43 and 44, as in the first embodiment.

<Third embodiment>
The secondary battery 1B of the present embodiment has a curved shape both when not used and when used, and has a metal case 51, a metal sealing plate 52, and an insulator 53 as an exterior body. The one with, is used. By using such an outer package, even if a battery element having a non-flexible shape, such as a battery element of an all-solid-state battery, is used as the electrode body 2, it is possible to prevent the electrode body 2 from being physically damaged. ..

Claim 15
Among them, the metal case 51 is a container on the negative electrode side that covers the electrode body 2 from the other end side in the stacking direction, is electrically connected to the negative electrode layer (second electrode layer) 12 of the electrode body 2, and also serves as a negative electrode terminal. is there. The metallic sealing plate 52 is a container on the positive electrode side that covers the electrode body 2 from one end side in the stacking direction, is electrically connected to the positive electrode layer (first electrode layer) 11 of the electrode body, and doubles as a positive electrode terminal. Further, the insulator 53 is provided so as to insulate the metal case 51 and the metal sealing plate 52 and fix them.

The exterior body in the present embodiment is provided by setting the electrode body 2 obtained in the first embodiment in a container including a metal case 51 and a metal sealing plate 52. Specifically, the negative electrode current collecting layer (second electrode current collecting layer) 22 constituting the other end portion in the stacking direction is set in the metal case 51 so as to be electrically conductive, and then the peripheral wall of the metal sealing plate 52. After inserting the portion 521 into the groove portion 511 of the gasket of the metal case 51, the peripheral wall portion 521 of the metal case 51 is crimped inward in the radial direction. As a result, the metal sealing plate 52 is fixed to the metal case 51, and the secondary battery 1B described above is manufactured.

1A, 1B Secondary battery 2 Electrode body
3 electrode assembly
11 Positive electrode layer (first electrode layer)
12 Negative electrode layer (second electrode layer)
13 Electrolyte Layer 14 Positive Electrode Current Collection Layer 15 Positive Electrode Connection Layer 16 First Opening 26 Second Opening 17, 17 Short Circuit Preventing Layer 22 Negative Electrode Current Collection Layer 23 Negative Electrode Connection Layer 31, 32 Conductive Member 41, 42 Tab Wire 43, 44 Laminate member 51 Metal case 511 Groove portion 52 Metal sealing plate 521 Peripheral wall portion 53 Insulators C1, C2 Cutting line

Claims (15)

A plate-shaped electrochemical cell having a curved shape at least in part at least during use,
A first electrode layer,
A second electrode layer laminated on both sides of the first electrode layer sandwiching a first electrolyte layer,
Having an electrode body including
At least one first opening penetrating the first electrode layer is provided,
An electrochemical cell in which the second electrode layers on both sides of the first electrode layer conduct inside the first opening,
The first opening is formed so as to be curved toward the stacking direction of the electrode bodies at least when in use, and has a length in the longitudinal direction of 1.2 times the width in the width direction perpendicular to the longitudinal direction. Configured to be more than double,
An electrochemical cell in which the first opening is formed so that at least a part thereof is curved during use. The electrochemical cell according to claim 1, wherein a second electrolyte layer is provided so as to cover the first opening of the first electrode layer. The electrochemical cell according to claim 1 or 2, wherein the first electrode layer has a plate shape that is curved at least in part at least during use. The electrochemical cell according to any one of claims 1 to 3, wherein the first opening is formed so as to be curved in the longitudinal direction at least when in use. At least when in use, at least a part of the surface of the first electrode layer adjacent to the first electrolyte layer forms a substantially partial cylindrical surface or a substantially partial elliptic cylindrical surface,
The electrochemical cell according to claim 4, wherein the longitudinal direction of the first opening forms an angle of 45° to 135° with respect to the direction of the central axis of the substantially cylindrical or substantially elliptic cylinder. The electrochemical cell according to claim 1, wherein a plurality of the first openings are formed on the same straight line in a plan view of the first electrode layer or the second electrode layer . The said 1st opening part is an electrochemical cell in any one of Claim 1 to 6 comprised so that the said length is 2.4 mm or more and the said width|variety is 2.0 mm or less. It said first electrode layer, a solid electrolyte, polymer electrolyte, or a solid electrolyte electrochemical cell according to any one of claims 1 to 7 containing composite electrolyte in the polymer electrolyte. The inner wall of the first opening, a solid electrolyte, a polymer electrolyte, a composite electrolyte of the solid electrolyte and the polymer electrolyte, or covered with an insulating material, electrochemical cell according to any one of claims 1 to 8. Wherein said second electrode layer on both sides of the first opening, electrochemical cell according to claim 1 which is in contact via the conductive member 9. Having a first electrode layer laminated on both sides of the second electrode layer with the first electrolyte layer interposed therebetween,
At least one second opening penetrating the second electrode layer is provided,
Inside the second opening, an electrochemical cell in which the first electrode layers on both sides of the second electrode layer conduct,
The second opening is formed so as to be curved toward the stacking direction of the electrode bodies at least when in use, and has a length in the longitudinal direction of 1.2 times the width in the width direction perpendicular to the longitudinal direction. It is configured to include a part that is more than double,
The electrochemical cell according to any one of claims 1 to 10 , wherein the second opening is formed so that at least a part thereof is curved at least during use. A plurality of the first electrode layers and a plurality of the second electrode layers are alternately laminated with the first electrolyte layer interposed therebetween,
The first electrode layer at one end in the stacking direction, the second electrode layer is provided at the other end,
The first opening is provided so as to penetrate each of the first electrode layers provided other than the one end,
The electrochemical cell according to claim 11 , wherein the second opening is provided so as to penetrate each of the second electrode layers provided other than the other end. The electrochemical cell according to any one of claims 1 to 12 , further comprising an exterior body that houses the electrode body. The exterior body includes a first electrode side container that covers the electrode body from one end side in the stacking direction, and a second electrode side container that covers the electrode body from the other end side in the stacking direction,
The electrochemical cell according to claim 13 , wherein the first electrode layer is electrically connected to the first electrode side container, and the second electrode layer is electrically connected to the second electrode side container. The electrochemical cell according to any one of claims 1 to 14 , wherein one of the first electrode layer and the second electrode layer is a positive electrode layer and the other is a negative electrode layer.

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