Battery

Abstract

This battery comprises: power-generating elements that include a first electrode, a second electrode, and an electrolyte layer that is positioned between the first electrode and the second electrode; and a first lead-out electrode. The first electrode includes: a first collector; and a first active material layer positioned between the first collector and the electrolyte layer. The first lead-out electrode includes: a first electroconductive member that is connected to a first surface of the first collector, the first surface being on the opposite side to the first active material layer; and a first lead that is connected to the first electroconductive member.

Description

[Technical Field]

[0001] The present disclosure relates to batteries. [Background technology]

[0002] Patent Documents 1 and 2 disclose batteries equipped with current collecting terminals. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2010-140703 [Patent Document 2] International Publication No. 2018 / 025649 Summary of the Invention [Problem to be solved by the invention]

[0004] There is a demand for improved battery reliability. [Means for solving the problem]

[0005] A battery according to one embodiment of the present disclosure comprises a power generating element including a first electrode, a second electrode, and an electrolyte layer located between the first electrode and the second electrode, and a first extraction electrode, wherein the first electrode includes a first current collector and a first active material layer located between the first current collector and the electrolyte layer, and the first extraction electrode includes a first conductive member connected to a first surface of the first current collector opposite to the first active material layer, and a first lead connected to the first conductive member. [Effects of the Invention]

[0006] According to the present disclosure, a highly reliable battery can be provided. [Brief explanation of the drawings]

[0007] [Figure 1] FIG. 1 is a perspective view showing the configuration of a conventional battery. [Figure 2] FIG. 2 is a cross-sectional view of the battery taken along line II-II in FIG. [Figure 3] FIG. 3 is a plan view and a cross-sectional view of the battery according to the first embodiment. [Figure 4] FIG. 4 is a flowchart showing a method for manufacturing a battery according to the first embodiment. [Figure 5] FIG. 5 is a plan view and a cross-sectional view of the battery according to the second embodiment. [Figure 6] FIG. 6 is a flowchart showing a method for manufacturing a battery according to the second embodiment. [Figure 7] FIG. 7 is a plan view and a cross-sectional view of a battery according to the third embodiment. [Figure 8] FIG. 8 is a plan view and a cross-sectional view of a battery according to the fourth embodiment. [Figure 9] FIG. 9 is a plan view and a cross-sectional view of a battery according to the fifth embodiment. [Figure 10] FIG. 10 is a plan view and a cross-sectional view of a battery according to the sixth embodiment. [Figure 11] FIG. 11 is a plan view and a cross-sectional view of a battery according to the seventh embodiment. [Figure 12] FIG. 12 is a plan view and a cross-sectional view of a battery according to a modification of the seventh embodiment. [Figure 13] FIG. 13 is a plan view of an extraction electrode according to the first modification of the embodiment. [Figure 14] FIG. 14 is a plan view and a cross-sectional view of an extraction electrode according to the second modification of the embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0008] (Findings that formed the basis of this disclosure) The present inventors have found that the following problems occur with conventional batteries.

[0009] Fig. 1 is a perspective view showing the configuration of a conventional battery 1x, and Fig. 2 is a cross-sectional view of the battery 1x taken along line II-II in Fig. 1.

[0010] As shown in Figures 1 and 2, the conventional battery 1x is an all-solid-state battery including a positive electrode 11x, a negative electrode 14x, and a solid electrolyte layer 17x. The positive electrode 11x includes a positive electrode current collector 12x and a positive electrode active material layer 13x. The negative electrode 14x includes a negative electrode current collector 15x and a negative electrode active material layer 16x. The solid electrolyte layer 17x is provided between the positive electrode 11x and the negative electrode 14x.

[0011] In a conventional battery 1x, as shown in FIGS. 1 and 2, a tab 18x is provided on a positive electrode current collector 12x. The tab 18x is a portion of the positive electrode current collector 12x that is not covered by the positive electrode active material layer 13x. A lead 22x is attached to the tab 18x. Similarly, a tab 19x is provided on a negative electrode current collector 15x. The tab 19x is a portion of the negative electrode current collector 15x that is not covered by the negative electrode active material layer 16x. A lead 32x is attached to the tab 19x. The leads 22x and 32x are extraction electrodes of the battery 1x.

[0012] When manufacturing the battery 1x, a laminate including the positive electrode 11x, the solid electrolyte layer 17x, and the negative electrode 14x is pressed and compressed in the thickness direction (hereinafter referred to as bonding press). By performing bonding press, the density of each of the positive electrode active material layer 13x, the negative electrode active material layer 16x, and the solid electrolyte layer 17x can be improved, and a good contact interface between the particles can be formed.

[0013] When the joining press is performed, each layer elongates in a direction perpendicular to the compression direction. The outer peripheral edge, which is the open end of each layer, is most affected by the strain caused by this elongation. As a result, the film thickness of each layer may differ between the center and the outer peripheral edge of the battery 1x. In this case, the outer peripheral edge of the battery 1x does not have the designed film thickness configuration, and therefore the designed battery performance cannot be obtained. This is one of the factors that reduces the reliability of the entire battery, including the outer peripheral edge.

[0014] One possible solution to this problem is to remove the outer peripheral edge. In other words, by cutting and removing the outer peripheral edge where the designed film thickness configuration is not achieved, it is possible to realize a battery 1x with uniform characteristics over the entire surface.

[0015] However, in the case of the battery 1x shown in Figures 1 and 2, the outer peripheral edge must be cut while leaving the tabs 18x and 19x. This requires extremely high cutting accuracy. Therefore, it is difficult to realize a highly reliable battery 1x in which the outer peripheral edge is cut while the tabs 18x and 19x are formed.

[0016] As described above, the conventional battery 1x has a problem in that it is not possible to improve reliability.

[0017] In contrast, a battery according to one embodiment of the present disclosure includes a power generating element including a first electrode, a second electrode, and an electrolyte layer located between the first electrode and the second electrode, and a first extraction electrode. The first electrode includes a first current collector and a first active material layer located between the first current collector and the electrolyte layer. The first extraction electrode includes a first conductive member connected to a first surface of the first current collector opposite to the first active material layer, and a first lead connected to the first conductive member.

[0018] Since the first lead is connected to the first current collector via the first conductive member, the first lead can be attached to the first current collector after, for example, cutting the outer peripheral edge of the power generating element. This eliminates the need for high precision in cutting the outer peripheral edge, and allows for a simple improvement in the reliability of the performance of the power generating element. Therefore, this aspect provides a highly reliable battery.

[0019] Leads generally have a thickness of about 100 μm. When leads are directly connected to current collectors, localized unevenness equivalent to the thickness of the leads occurs at the connection points. During actual use, batteries may be subjected to large external confining pressure. In this case, if localized unevenness exists on the current collector, the confining pressure that the battery receives will also vary. This variation in confining pressure may locally accelerate the deterioration of battery performance, reducing the reliability of the battery.

[0020] In contrast, in a battery according to an aspect of the present disclosure, for example, the first conductive member may have a region that does not overlap with the first current collector in a plan view, and the first lead may be connected to the first conductive member in the region.

[0021] This prevents the first lead from overlapping the first current collector, thereby reducing variations in the confining pressure that the power generating element receives, thereby further improving the reliability of the battery.

[0022] Furthermore, for example, the first conductive member may be in contact with the first surface of the first current collector.

[0023] This reduces the contact resistance between the first conductive member and the first current collector, thereby improving the efficiency of battery removal.

[0024] For example, the battery according to one aspect of the present disclosure may further include an adhesive layer located between the first current collector and the first conductive member, and the first conductive member may be connected to the first surface of the first current collector via the adhesive layer.

[0025] This increases the bonding strength between the first conductive member and the first current collector, thereby preventing the first conductive member and the first lead from becoming detached from the power generating element, thereby improving the reliability of the battery.

[0026] Furthermore, for example, the adhesive layer may be electrically conductive.

[0027] This increases the bonding strength between the first conductive member and the first current collector, while also increasing the efficiency of battery removal.

[0028] Furthermore, for example, the first current collector and the first conductive member may be formed using the same material, i.e., the first current collector and the first conductive member may contain the same material.

[0029] This can improve the adhesion between the first conductive member and the first current collector, further reducing the contact resistance between the first conductive member and the first current collector, and thus further improving the removal efficiency of the battery.

[0030] Furthermore, for example, the thickness of the conductive member may be equal to or greater than the thickness of the first current collector.

[0031] This increases the strength of the first conductive member, thereby preventing breakage, etc., and therefore improving the reliability of the battery.

[0032] Furthermore, for example, the battery according to one aspect of the present disclosure may further include an insulating layer provided in a frame shape along an end face of the power generating element.

[0033] This makes it possible to prevent short circuits between the positive electrode and the negative electrode at the ends of the power generating element, thereby improving the reliability of the battery.

[0034] Furthermore, for example, the insulating layer may further cover an end portion of the first surface of the first current collector.

[0035] This allows the outer peripheral edge of the first conductive member to be protected by the insulating layer, thereby improving the reliability of the battery.

[0036] Furthermore, for example, the first conductive member may cover the entire first surface of the first current collector in a plan view.

[0037] This maximizes the contact area between the first conductive member and the first current collector, reducing the contact resistance between the first conductive member and the first current collector and thereby improving the efficiency of battery removal.

[0038] Furthermore, for example, the sheet resistance of the first conductive member may decrease as it becomes more distant from the first lead.

[0039] This makes it possible to suppress localized electric field concentration, thereby suppressing localized deterioration of the battery, and thus improving the reliability of the battery.

[0040] Furthermore, for example, the first conductive member may be provided with a plurality of through holes, and at least one of an arrangement density and an opening area of ​​the plurality of through holes may decrease with increasing distance from the first lead.

[0041] This makes it possible to suppress localized electric field concentration while maintaining a uniform thickness of the first conductive member, for example. The uniform thickness of the first conductive member makes it possible to suppress variations in the confining pressure applied to the power generating element, thereby further improving the reliability of the battery.

[0042] Furthermore, for example, the thickness of the first conductive member may increase as it becomes farther away from the first lead.

[0043] This makes it possible to easily suppress localized electric field concentration by varying the thickness of the first conductive member, thereby improving the efficiency of battery removal.

[0044] For example, the battery according to one embodiment of the present disclosure may further include a second extraction electrode. The second electrode includes a second current collector and a second active material layer located between the second current collector and the electrolyte layer. The second extraction electrode may include a second conductive member connected to a second surface of the second current collector opposite the second active material layer, and a second lead connected to the second conductive member.

[0045] Since the second lead is connected to the second current collector via the second conductive member, for example, the second lead can be attached to the second current collector after cutting the outer peripheral edge of the power generating element. This eliminates the need for high precision in cutting the outer peripheral edge, and allows the reliability of the performance of the power generating element to be easily improved. Therefore, this aspect makes it possible to provide a highly reliable battery.

[0046] Furthermore, for example, the first conductive member may protrude in a first direction from the power generating element in a plan view. The second conductive member may protrude in a second direction from the power generating element in a plan view. The first lead may be connected to the protruding portion of the first conductive member. The second lead may be connected to the protruding portion of the second conductive member.

[0047] This prevents the first conductive member and the second conductive member from overlapping the power generating element in a plan view, thereby reducing variations in the confining pressure that the power generating element receives, thereby further improving the reliability of the battery.

[0048] Furthermore, for example, the first direction and the second direction may be opposite directions.

[0049] This allows the first lead and the second lead to be spaced apart, thereby preventing short circuits and improving the reliability of the battery.

[0050] Furthermore, for example, the first direction and the second direction may be the same direction.

[0051] This allows the first lead and the second lead to be located close to each other, which is suitable for cases where the mounting area is limited. For example, when the battery is mounted on a substrate, the area required for connecting the substrate and the battery can be reduced, which increases the degree of freedom in the layout of other circuit elements, wiring, etc. mounted on the substrate.

[0052] Furthermore, for example, the first direction and the second direction may be perpendicular to each other.

[0053] This allows the lead-out directions of the positive and negative electrodes of the battery to be adjusted according to requirements at the time of mounting.

[0054] Furthermore, for example, the electrolyte layer may include a solid electrolyte having lithium ion conductivity.

[0055] This makes it possible to provide a highly reliable all-solid-state battery.

[0056] Furthermore, for example, a battery according to one embodiment of the present disclosure may include a plurality of the power generating elements. The first extraction electrode may be connected to the first current collector of a first power generating element, which is one of the plurality of power generating elements. A second power generating element, which is one of the plurality of power generating elements, may be stacked on the second electrode side of the first power generating element.

[0057] As a result, since the battery includes a plurality of power generating elements, it is possible to realize a battery that has high output voltage and / or high battery capacity, and is highly reliable.

[0058] Furthermore, for example, the second electrode of the first power generating element may be connected to the first electrode of the second power generating element.

[0059] This allows the voltage drawn from the battery to be increased.

[0060] Furthermore, for example, the second electrode of the first power generating element may be connected to the second electrode of the second power generating element.

[0061] This allows the battery capacity to be increased.

[0062] Hereinafter, the embodiments will be specifically described with reference to the drawings.

[0063] The embodiments described below are all comprehensive or specific examples. The numerical values, shapes, materials, components, component placement and connection configurations, steps, and step order shown in the following embodiments are merely examples and are not intended to limit the present disclosure. Furthermore, among the components in the following embodiments, components not described in the independent claims are described as optional components.

[0064] Furthermore, each figure is a schematic diagram and is not necessarily an exact illustration. Therefore, for example, the scales of the figures do not necessarily match. Furthermore, in each figure, substantially the same components are given the same reference numerals, and redundant explanations are omitted or simplified.

[0065] Furthermore, in this specification, terms indicating the relationship between elements, such as parallel or perpendicular, terms indicating the shape of elements, such as rectangular or circular, and numerical ranges are not expressions that only express a strict meaning, but are expressions that also include a substantially equivalent range, for example, a difference of about a few percent.

[0066] In this specification and drawings, the x-axis, y-axis, and z-axis represent the three axes of a three-dimensional Cartesian coordinate system. In each embodiment, the z-axis direction is the thickness direction of the battery. In this specification, the "thickness direction" refers to the direction perpendicular to the surface on which each layer is stacked. The positive side of the z-axis may simply be referred to as "upper" and "upper side," and the negative side of the z-axis may simply be referred to as "lower" and "lower side." For example, the surface of each layer of the battery on the positive side of the z-axis may be referred to as the "upper surface," and the surface on the negative side of the z-axis may be referred to as the "lower surface."

[0067] In addition, in this specification, "plan view" means a view of the battery along the stacking direction of the battery, and "thickness" in this specification means the length of the battery and each layer in the stacking direction.

[0068] In addition, in this specification, the terms "inside" and "outside" refer to the inside and outside when the battery is viewed along the stacking direction of the battery.

[0069] Furthermore, in this specification, the terms "upper" and "lower" in the battery configuration do not refer to the upper direction (vertically upper) and lower direction (vertically lower) in absolute spatial recognition, but are used as terms defined by a relative positional relationship based on the stacking order in the stacking configuration. Furthermore, the terms "upper" and "lower" are applied not only to a case where two components are arranged with a gap between them and another component exists between the two components, but also to a case where two components are arranged closely together and the two components are in contact with each other.

[0070] (Embodiment 1) [Battery Overview] First, the battery according to the first embodiment will be described with reference to FIG.

[0071] FIG. 3 shows a plan view and a cross-sectional view of the battery 1 according to this embodiment. Specifically, FIG. 3(a) is a plan view of the battery 1 as seen from the positive side of the z-axis. FIG. 3(b) shows a cross-section taken along line IIIb-IIIb in FIG. 3(a). FIG. 3(c) shows a cross-section taken along line IIIc-IIIc in FIG. 3(a). Note that FIG. 3(c) omits the illustration of the first lead 22, which is located deep in the cross-section. This also applies to the subsequent figures.

[0072] 3, the battery 1 includes a power generating element 10, a first extraction electrode 20, a second extraction electrode 30, and an insulating layer 40. The battery 1 is an all-solid-state battery.

[0073] The power generating element 10 includes a first electrode 11, a second electrode 14, and a solid electrolyte layer 17. The first electrode 11 includes a first current collector 12 and a first active material layer 13 disposed in contact with the first current collector 12. The second electrode 14 is a counter electrode of the first electrode 11. The second electrode 14 includes a second current collector 15 and a second active material layer 16 disposed in contact with the second current collector 15. The solid electrolyte layer 17 is an example of an electrolyte layer located between the first electrode 11 and the second electrode 14, and is in contact with both the first active material layer 13 and the second active material layer 16.

[0074] The power generating element 10 is a laminate of the first electrode 11, the second electrode 14, and the solid electrolyte layer 17, with the outer peripheral edge cut off. That is, the laminate in which the layers are stacked is subjected to a joining press, and the outer peripheral edge, which may cause variation in film thickness, is cut off to produce the power generating element 10. Therefore, the power generating element 10 has reduced variation in battery performance and improved reliability.

[0075] In this embodiment, the first and second extraction electrodes 20 and 30 are connected to the power generating element 10, which has high reliability after the outer peripheral end is cut off, thereby achieving a highly reliable battery 1.

[0076] The specific configurations of the power generating element 10, the first extraction electrode 20, and the second extraction electrode 30 will be described below.

[0077] [Power generation element] First, each component of the power generating element 10 will be described in detail.

[0078] In this embodiment, the first electrode 11 is a positive electrode, and the second electrode 14 is a negative electrode. That is, the first current collector 12 is a positive electrode current collector, and the first active material layer 13 contains a positive electrode active material. The second current collector 15 is a negative electrode current collector, and the second active material layer 16 contains a negative electrode active material.

[0079] The first electrode 11 may be a negative electrode and the second electrode 14 may be a positive electrode. That is, the first current collector 12 may be a negative electrode current collector and the first active material layer 13 may contain a negative electrode active material. The second current collector 15 may be a positive electrode current collector and the second active material layer 16 may contain a positive electrode active material.

[0080] The first current collector 12, the first active material layer 13, the solid electrolyte layer 17, the second active material layer 16, and the second current collector 15 each have a rectangular shape in a planar view. The planar shapes of the first current collector 12, the first active material layer 13, the solid electrolyte layer 17, the second active material layer 16, and the second current collector 15 are not particularly limited, and may be shapes other than a rectangle, such as a circle, an ellipse, or a polygon.

[0081] In the present embodiment, the first current collector 12, the first active material layer 13, the solid electrolyte layer 17, the second active material layer 16, and the second current collector 15 are all the same size and have the same outline in a plan view, but this is not limiting. For example, the first active material layer 13 may be smaller than the second active material layer 16. The first active material layer 13 and the second active material layer 16 may also be smaller than the solid electrolyte layer 17.

[0082] In this specification, when there is no particular need to distinguish between the first current collector 12 and the second current collector 15, they may be collectively referred to simply as "current collectors." The current collectors are not particularly limited as long as they are made of a conductive material.

[0083] Examples of current collectors include foils, plates, and meshes made of stainless steel, nickel (Ni), aluminum (Al), iron (Fe), titanium (Ti), copper (Cu), palladium (Pd), gold (Au), platinum (Pt), or alloys of two or more of these metals. The current collector material is appropriately selected based on the manufacturing process, the temperature and pressure at which it is used, and the operating potential and conductivity of the battery applied to the current collector. The current collector material can also be selected based on the required tensile strength and heat resistance. The current collector may be, for example, a high-strength electrolytic copper foil or a clad material made by laminating foils of different metals. In this embodiment, the first current collector 12 contains aluminum as a primary component. The second current collector 15 contains copper as a primary component.

[0084] The thickness of the current collector is, for example, in the range of 10 μm to 100 μm. The surface of the current collector may be roughened to improve adhesion with the first active material layer 13 or the second active material layer 16. The surface of the current collector may also be coated with an adhesive component such as an organic binder. This strengthens the bonding at the interface between the current collector and other layers, thereby improving the mechanical and thermal reliability and cycle characteristics of the battery 1.

[0085] The first active material layer 13 is located between the first current collector 12 and the solid electrolyte layer 17. Specifically, the first active material layer 13 is disposed in contact with the main surface of the first current collector 12 on the side of the solid electrolyte layer 17. In the present embodiment, the first active material layer 13 contains at least a positive electrode active material. That is, the first active material layer 13 is a layer mainly containing a positive electrode material such as a positive electrode active material.

[0086] The positive electrode active material is a substance in which metal ions such as lithium (Li) ions or magnesium (Mg) ions are inserted into or removed from the crystal structure at a potential higher than that of the negative electrode, and oxidation or reduction is performed accordingly. The type of the positive electrode active material can be appropriately selected according to the type of the battery 1, and a known positive electrode active material can be used.

[0087] Examples of the positive electrode active material include compounds containing lithium and a transition metal element, such as oxides containing lithium and a transition metal element, and phosphate compounds containing lithium and a transition metal element. Examples of the oxide containing lithium and a transition metal element include lithium nickel composite oxides such as LiNi x M 1-x O2 (where M is at least one element selected from Co, Al, Mn, V, Cr, Mg, Ca, Ti, Zr, Nb, Mo, and W, and x satisfies 0 < x ≤ 1), such as layered oxides like lithium cobaltate (LiCoO2), lithium nickelate (LiNiO2), lithium manganate (LiMn2O4), or lithium manganate having a spinel structure (for example, LiMn2O4, Li2MnO3, LiMnO2). Examples of the phosphate compound containing lithium and a transition metal element include lithium iron phosphate (LiFePO4) having an olivine structure. In addition, sulfides such as sulfur (S) and lithium sulfide (Li2S) can also be used as the positive electrode active material. In that case, a material obtained by coating or adding lithium niobate (LiNbO3) or the like to the positive electrode active material particles can be used as the positive electrode active material. Note that only one of these materials may be used as the positive electrode active material, or two or more of these materials may be combined and used.

[0088] As described above, the first active material layer 13, which is a positive electrode active material layer, only needs to contain at least a positive electrode active material. The first active material layer 13 may be a mixture layer composed of a mixture of a positive electrode active material and other additive materials. Examples of other additive materials that can be used include solid electrolytes such as inorganic solid electrolytes or sulfide-based solid electrolytes, conductive additives such as acetylene black, and adhesive binders such as polyethylene oxide or polyvinylidene fluoride. By mixing the positive electrode active material and other additive materials, such as a solid electrolyte, in a predetermined ratio, the first active material layer 13 can improve both the lithium ion conductivity and the electronic conductivity within the first active material layer 13.

[0089] The thickness of the first active material layer 13 is, for example, in the range of 5 μm to 300 μm, but is not limited to this.

[0090] The second active material layer 16 is located between the second current collector 15 and the solid electrolyte layer 17. Specifically, the second active material layer 16 is disposed in contact with the main surface of the second current collector 15 on the solid electrolyte layer 17 side. In the present embodiment, the second active material layer 16 contains at least a negative electrode active material. That is, the second active material layer 16 is a layer that mainly contains a negative electrode material such as a negative electrode active material.

[0091] The negative electrode active material is a material in which metal ions such as lithium (Li) ions or magnesium (Mg) ions are inserted or extracted into or from the crystalline structure at a potential lower than that of the positive electrode, and oxidation or reduction occurs accordingly. The type of negative electrode active material can be appropriately selected depending on the type of battery 1, and known negative electrode active materials can be used.

[0092] Examples of the negative electrode active material include carbon materials such as natural graphite, artificial graphite, graphite carbon fiber, and resin-baked carbon, as well as alloy materials that are mixed with a solid electrolyte. Examples of alloy materials include LiAl, LiZn, LiBi, LiCd, LiSb, LiSi, and Li. 4.4 Pb, Li 4.4 Sn, Li 0.17C or lithium alloys such as LiC6, lithium titanate (Li4Ti5O 12 ), zinc oxide (ZnO), or silicon oxide (SiO x ) and other metal oxides can be used. The negative electrode active material may be made of only one of these materials, or a combination of two or more of these materials.

[0093] As described above, the second active material layer 16, which is a negative electrode active material layer, only needs to contain at least a negative electrode active material. The second active material layer 16 may be a mixture layer composed of a mixture of a negative electrode active material and other additive materials. Examples of other additive materials that can be used include solid electrolytes such as inorganic solid electrolytes or sulfide-based solid electrolytes, conductive additives such as acetylene black, and adhesive binders such as polyethylene oxide or polyvinylidene fluoride. By mixing the negative electrode active material and other additive materials, such as a solid electrolyte, in a predetermined ratio, the second active material layer 16 can improve both lithium ion conductivity and electronic conductivity.

[0094] The thickness of the second active material layer 16 is, for example, in the range of 5 μm to 300 μm, but is not limited to this.

[0095] The solid electrolyte layer 17 is disposed between the first active material layer 13 and the second active material layer 16 and is in contact with each other. The solid electrolyte layer 17 includes at least a solid electrolyte. The solid electrolyte layer 17 includes, for example, the solid electrolyte as a main component.

[0096] The solid electrolyte may be any known ion-conductive solid electrolyte for batteries. For example, a solid electrolyte that conducts metal ions such as lithium ions or magnesium ions may be used. The type of solid electrolyte may be appropriately selected depending on the type of ions to be conducted.

[0097] The solid electrolyte may be, for example, an inorganic solid electrolyte such as a sulfide-based solid electrolyte or an oxide-based solid electrolyte. Examples of the sulfide-based solid electrolyte include lithium-containing sulfides such as Li2S-P2S5, Li2S-SiS2, Li2S-B2S3, Li2S-GeS2, Li2S-SiS2-LiI, Li2S-SiS2-Li3PO4, Li2S-Ge2S2, Li2S-GeS2-P2S5, or Li2S-GeS2-ZnS. Examples of the oxide-based solid electrolyte include lithium-containing metal oxides such as Li2O-SiO2 or Li2O-SiO2-P2O5, and Li2S-GeS2-ZnS. x P y O 1-z N z Lithium-containing metal nitrides such as lithium phosphate (LiPO), lithium-containing transition metal oxides such as lithium titanium oxide, etc., can be used. As the solid electrolyte, only one of these materials may be used, or two or more of these materials may be used in combination. In the present embodiment, the solid electrolyte layer 17 includes, as an example, a solid electrolyte having lithium ion conductivity.

[0098] In addition to the above solid electrolyte material, the solid electrolyte layer 17 may contain an adhesive binder such as polyethylene oxide or polyvinylidene fluoride.

[0099] The thickness of the solid electrolyte layer 17 is, for example, in the range of 5 μm to 150 μm, but is not limited to this.

[0100] The solid electrolyte material may be configured as an aggregate of particles, or may be configured as a sintered structure.

[0101] [First extraction electrode and second extraction electrode] Next, the first extraction electrode 20 and the second extraction electrode 30 will be described in detail.

[0102] 3, the first extraction electrode 20 includes a first conductive member 21 and a first lead 22. The second extraction electrode 30 includes a second conductive member 31 and a second lead 32.

[0103] The first conductive member 21 is connected to the main surface 12a of the first current collector 12. The main surface 12a is a first surface of the first current collector 12 opposite to the first active material layer 13. In this embodiment, as shown in FIGS. 3(b) and 3(c), the first conductive member 21 is in contact with the main surface 12a of the first current collector 12. The first conductive member 21 and the first current collector 12 are in surface contact with each other so as to increase the contact area.

[0104] In this embodiment, the first conductive member 21 covers the entire main surface 12a of the first current collector 12 in plan view. The outline of the main surface 12a matches the outline of the power generating element 10 shown in FIG. 3(a). The first conductive member 21 is larger than the first current collector 12 in plan view. The first conductive member 21 has a region 21a that does not overlap with the first current collector 12 in plan view.

[0105] The first conductive member 21 is a flat, conductive member. Specifically, the first conductive member 21 is a metal foil. Examples of materials that can be used to form the first conductive member 21 include stainless steel, nickel, aluminum, iron, titanium, copper, palladium, gold, platinum, and alloys of two or more of these metals. The first conductive member 21 is formed using the same material as the first current collector 12, for example. That is, the first conductive member 21 may contain the same material as the first current collector 12, for example. For example, if the first current collector 12 is a metal foil containing aluminum as a main component, the first conductive member 21 also contains aluminum as a main component.

[0106] The thickness of the first conductive member 21 is, for example, in the range of 10 μm to 100 μm. The thickness of the first conductive member 21 is equal to or greater than the thickness of the first current collector 12. For example, when the thickness of the first conductive member 21 is greater than the thickness of the first current collector 12, the strength of the first conductive member 21 can be increased.

[0107] The first lead 22 is connected to the first conductive member 21. Specifically, the first lead 22 is connected to the first conductive member 21 in a region 21a. The region 21a is a part of the first conductive member 21, and is a portion that protrudes from the power generating element 10 in a first direction in a planar view. Specifically, the first direction is the negative direction of the x-axis. The region 21a is, for example, a portion of the first conductive member 21 that does not overlap with the second conductive member 31 in a planar view. As shown in FIG. 3(b), the first lead 22 is connected to a main surface of the first conductive member 21 that faces the power generating element 10.

[0108] The first lead 22 is a wire-, foil-, or plate-shaped member made of a metal such as copper, aluminum, nickel, or stainless steel, or a plated member of any of these metals. The first lead 22 has a thickness of, for example, 100 μm. The first lead 22 is formed using, for example, the same material as the first conductive member 21. That is, the first lead 22 may include, for example, the same material as the first conductive member 21. The first lead 22 is ultrasonically connected to the first conductive member 21, for example. The first lead 22 and the first conductive member 21 may be connected using a conductive adhesive such as solder.

[0109] The first lead 22 is elongated in one direction. In this embodiment, as shown in FIG. 3(a), the planar shape of the first lead 22 is a rectangle elongated in the y-axis direction. The first lead 22 is extended in the positive direction of the y-axis relative to the first conductive member 21. The tip portion of the first lead 22 in the extension direction is extended from a laminate member (not shown) that seals almost the entire battery 1, and is used for electrical and physical connection to other substrates, etc.

[0110] The second conductive member 31 is connected to the main surface 15a of the second current collector 15. The main surface 15a is the second surface of the second current collector 15 opposite to the second active material layer 16. In this embodiment, as shown in FIGS. 3(b) and 3(c), the second conductive member 31 is in contact with the main surface 15a of the second current collector 15. The second conductive member 31 and the second current collector 15 are in surface contact with each other so as to increase the contact area.

[0111] In this embodiment, the second conductive member 31 covers the entire main surface 15a of the second current collector 15 in plan view. The outline of the main surface 15a matches the outline of the power generating element 10 shown in FIG. 3(a). The second conductive member 31 is larger than the second current collector 15 in plan view. The second conductive member 31 has a region 31a that does not overlap with the second current collector 15 in plan view.

[0112] The second conductive member 31 is a flat, conductive member. Specifically, the second conductive member 31 is a metal foil. Examples of materials that can be used to form the second conductive member 31 include stainless steel, nickel, aluminum, iron, titanium, copper, palladium, gold, platinum, and alloys of two or more of these metals. The second conductive member 31 is formed using the same material as the second current collector 15, for example. That is, the second conductive member 31 may contain the same material as the second current collector 15, for example. For example, if the second current collector 15 is a metal foil containing copper as a main component, the second conductive member 31 also contains copper as a main component.

[0113] The thickness of the second conductive member 31 is, for example, in the range of 10 μm to 100 μm. The thickness of the second conductive member 31 is equal to or greater than the thickness of the second current collector 15. For example, when the thickness of the second conductive member 31 is greater than the thickness of the second current collector 15, the strength of the second conductive member 31 can be increased.

[0114] The second lead 32 is connected to the second conductive member 31. Specifically, the second lead 32 is connected to the second conductive member 31 in a region 31a. The region 31a is a part of the second conductive member 31 and is a portion that protrudes from the power generating element 10 in a second direction in a planar view. The second direction is specifically the positive direction of the x-axis. That is, in this embodiment, the first direction and the second direction are opposite directions. The region 31a is, for example, a portion of the second conductive member 31 that does not overlap with the first conductive member 21 in a planar view. As shown in FIG. 3(b), the second lead 32 is connected to a main surface of the second conductive member 31 that faces the power generating element 10.

[0115] The second lead 32 is a wire-, foil-, or plate-shaped member made of a metal such as copper, aluminum, nickel, or stainless steel, or a plated member of any of these metals. The second lead 32 has a thickness of, for example, 100 μm. The second lead 32 is formed using, for example, the same material as the second conductive member 31. That is, the second lead 32 may contain, for example, the same material as the second conductive member 31. The second lead 32 is ultrasonically connected to the second conductive member 31, for example. The second lead 32 and the second conductive member 31 may be connected using a conductive adhesive such as solder.

[0116] The second lead 32 is elongated in one direction. In this embodiment, as shown in FIG. 3(a), the planar shape of the second lead 32 is a rectangle elongated in the y-axis direction. The second lead 32 is extended in the positive direction of the y-axis relative to the second conductive member 31. In this embodiment, the extension direction of the second lead 32 is the same as the extension direction of the first lead 22. The tip portion of the second lead 32 in the extension direction is extended from a laminate member (not shown) that seals almost the entire battery 1, and is used for electrical and physical connection to other substrates, etc.

[0117] 3(a), the first lead 22 and the second lead 32 are arranged to sandwich the power generating element 10 in a plan view. That is, in a plan view, the power generating element 10 is located between the first lead 22 and the second lead 32. The first conductive member 21 and the second conductive member 31 are rectangular and of the same size in a plan view, and are arranged with a shift in the longitudinal direction. The power generating element 10 and the insulating layer 40 are located in the overlapping portion between the first conductive member 21 and the second conductive member 31.

[0118] In this embodiment, the connection between the first extraction electrode 20 and the power generating element 10, and the connection between the second extraction electrode 30 and the power generating element 10, are maintained by a laminate member (not shown) that seals the battery 1. The laminate member is a sealing member intended to protect the battery 1, and is made of a metal material or a resin material. Except for the tip portions of the first lead 22 and the second lead 32, the entire battery 1 is vacuum-sealed by the laminate member.

[0119] By creating a vacuum inside the laminate member, atmospheric pressure can apply a restraining force in the thickness direction to the power generating element 10 of the battery 1 via the laminate member. The restraining force of the laminate member causes the first conductive member 21 to adhere closely to the first current collector 12, and the second conductive member 31 to adhere closely to the second current collector 15. This reduces the contact resistance between the first conductive member 21 and the first current collector 12, and the contact resistance between the second conductive member 31 and the second current collector 15. Furthermore, the restraining force of the laminate member can suppress misalignment between the first conductive member 21 and the first current collector 12, and between the second conductive member 31 and the second current collector 15, etc.

[0120] [Insulating layer] The insulating layer 40 is an insulating layer provided in a frame shape along the end faces of the power generating element 10. The insulating layer 40 covers the entire periphery of the power generating element 10 in a plan view so that the end faces of the power generating element 10 are not exposed.

[0121] The insulating layer 40 is formed using a commonly known material for sealing a battery, such as a sealant. For example, the insulating layer 40 is formed using an insulating resin material. Examples of insulating resin materials that can be used include epoxy resin, acrylic resin, and polyimide resin.

[0122] The width of the insulating layer 40 is, for example, several μm or more, but is not limited to this.

[0123] [Manufacturing method] Next, a method for manufacturing the battery 1 according to this embodiment will be described with reference to Fig. 4. Fig. 4 is a flowchart showing the method for manufacturing the battery 1 according to this embodiment.

[0124] 4, first, a laminate having the same configuration as the power generating element 10 is formed (S10). The laminate is the power generating element 10 before being subjected to joining press and cutting of the outer peripheral edge, and includes a first electrode 11, a solid electrolyte layer 17, and a second electrode 14 before being subjected to joining press and cutting of the outer peripheral edge. A known method for forming a power generating element can be used as a method for forming the laminate.

[0125] Next, the formed laminate is subjected to a joining press (S12). This allows the central portion of the laminate to achieve the designed battery characteristics. After the joining press, the outer peripheral edge of the laminate is cut (S14). This allows the formation of a highly reliable power generating element 10 with little in-plane variation in battery performance.

[0126] Next, the insulating layer 40 is formed (S16). For example, the insulating layer 40 is formed by applying a resin material along the outer periphery of the power generating element 10 so as to cover the entire end face of the power generating element 10, and then curing the resin material.

[0127] Next, the first extraction electrode 20 and the second extraction electrode 30 are formed (S18). Specifically, the first extraction electrode 20 is formed by ultrasonically connecting the first lead 22 to the end of the first conductive member 21. Similarly, the second extraction electrode 30 is formed by ultrasonically connecting the second lead 32 to the end of the second conductive member 31.

[0128] Next, the first extraction electrode 20 is connected to the first current collector 12, and the second extraction electrode 30 is connected to the second current collector 15 (S20). For example, the battery 1 is laminated and sealed after the first conductive member 21 and the first current collector 12 are aligned, and the second conductive member 31 and the second current collector 15 are aligned. As a result, the first extraction electrode 20 is connected to the first current collector 12, and the second extraction electrode 30 is connected to the second current collector 15. For alignment, adhesive tape or the like may be used to temporarily fix each extraction electrode to the power generating element 10. The adhesive tape is, for example, attached from the outer side of each of the first extraction electrode 20 and the second extraction electrode 30 to the insulating layer 40.

[0129] Instead of temporary fixing, the extraction electrode and the current collector may be fixed by ultrasonic welding, spot welding, etc. Furthermore, the first lead 22 and the second lead 32 may be connected during temporary fixing or after the extraction electrode and the current collector are fixed.

[0130] Furthermore, the formation of the insulating layer 40 (S16) may be omitted. That is, the battery 1 does not need to include the insulating layer 40. Furthermore, the formation of the first extraction electrode 20 and the second extraction electrode 30 (S18) may be performed before the formation of the laminate (S10), or may be performed in parallel with the formation of the power generating element (S10 to S14).

[0131] As described above, in the battery 1 according to this embodiment, the first lead 22 is connected to the first current collector 12 via the first conductive member 21. Therefore, as shown in Fig. 4, after the outer peripheral end of the power generating element 10 is cut, the first lead 22 can be attached to the first current collector 12 later. The same applies to the second lead 32 and the second current collector 15.

[0132] Therefore, high accuracy is not required for cutting the outer peripheral edge of the power generating element 10, and it is possible to easily improve the reliability of the performance of the power generating element 10. Therefore, according to this embodiment, it is possible to provide a highly reliable battery 1.

[0133] Moreover, because the first conductive member 21 and the second conductive member 31 each cover the entire surface of the power generating element 10, variation in the final confining pressure on the power generating element 10 is suppressed. Moreover, because the insulating layer 40 covers the end faces of the power generating element 10, short-circuiting between the first electrode 11 and the second electrode 14 can be suppressed.

[0134] (Embodiment 2) Next, a battery according to embodiment 2 will be described. In embodiment 2, the main difference from embodiment 1 is that the insulating layer covering the end faces of the power generating element covers the end of the first surface of the first current collector and the end of the second surface of the second current collector. The following description will focus on the differences from embodiment 1, and description of the commonalities will be omitted or simplified.

[0135] Fig. 5 shows a plan view and a cross-sectional view of a battery 101 according to this embodiment. Specifically, Fig. 5(a) is a plan view of the battery 101 as seen from the positive side of the z-axis. Fig. 5(b) shows a cross-section taken along line Vb-Vb in Fig. 5(a). Fig. 5(c) shows a cross-section taken along line Vc-Vc in Fig. 5(a).

[0136] 5, the battery 101 includes a power generating element 10, a first extraction electrode 120, a second extraction electrode 130, and an insulating layer 140. The power generating element 10 is the same as in the first embodiment, and therefore a description thereof will be omitted.

[0137] The first extraction electrode 120 includes a first conductive member 121 and a first lead 22. The second extraction electrode 130 includes a second conductive member 131 and a second lead 32. The first lead 22 and the second lead 32 are both the same as those in the first embodiment.

[0138] The first conductive member 121 differs in size from the first conductive member 21 according to the first embodiment. In the present embodiment, the first conductive member 121 does not cover the entire main surface 12a of the first current collector 12, but only a portion of it. As shown in FIG. 5 , the first conductive member 121 exposes the outer peripheral edge of the main surface 12a of the first current collector 12. Specifically, the main surface 12a of the first current collector 12 has a rectangular shape in a plan view, and the first conductive member 121 does not cover three sides of the main surface 12a, but covers only one side of the main surface 12a. In other words, the three sides of the first conductive member 121 are located more inward than the three sides of the first current collector 12 in a plan view.

[0139] The first conductive member 121 has a region 121a that does not overlap the first current collector 12 in plan view. The region 121a is a part of the first conductive member 121, and is a portion that protrudes in the negative direction of the x-axis from the power generating element 10 in plan view. The first lead 22 is connected to the region 121a.

[0140] The second conductive member 131 differs in size from the second conductive member 31 according to the first embodiment. In the present embodiment, the second conductive member 131 does not cover the entire main surface 15a of the second current collector 15, but only a portion of it. As shown in FIG. 5 , the second conductive member 131 exposes the outer peripheral edge of the main surface 15a of the second current collector 15. Specifically, the main surface 15a of the second current collector 15 has a rectangular shape in a plan view, and the second conductive member 131 does not cover three sides of the main surface 15a, but covers only one side of the main surface 15a. In other words, the three sides of the second conductive member 131 are located more inward than the three sides of the second current collector 15 in a plan view.

[0141] The second conductive member 131 has a region 131a that does not overlap the second current collector 15 in plan view. The region 131a is a part of the second conductive member 131, and is a portion that protrudes in the positive direction of the x-axis from the power generating element 10 in plan view. A second lead 32 is connected to the region 131a.

[0142] Similar to the insulating layer 40 according to the first embodiment, the insulating layer 140 is provided in a frame shape along the end face of the power generating element 10. The insulating layer 140 also covers the end of the main surface 12a of the first current collector 12. Specifically, the insulating layer 140 covers the portion of the main surface 12a of the first current collector 12 that is not covered by the first conductive member 121. For example, as shown in FIGS. 5(b) and 5(c), the insulating layer 140 is provided along the end face of the first conductive member 121. The insulating layer 140 and the end face of the first conductive member 121 are in contact with each other. The upper surface of the insulating layer 140 and the upper surface of the first conductive member 121 are flush with each other. The insulating layer 140 and the end face of the first conductive member 121 may be spaced apart.

[0143] The insulating layer 140 also covers the end portion of the main surface 15a of the second current collector 15. Specifically, the insulating layer 140 covers the portion of the main surface 15a of the second current collector 15 that is not covered by the second conductive member 131. For example, as shown in FIGS. 5(b) and 5(c), the insulating layer 140 is provided along the end face of the second conductive member 131. The insulating layer 140 and the end face of the second conductive member 131 are in contact with each other. The lower surface of the insulating layer 140 and the lower surface of the second conductive member 131 are flush with each other. The insulating layer 140 and the end face of the second conductive member 131 may be spaced apart.

[0144] The manufacturing method of battery 101 is different from the manufacturing method of battery 1 according to embodiment 1. Fig. 6 is a flowchart showing the manufacturing method of battery 101 according to this embodiment.

[0145] As shown in FIG. 6 , the steps (S10 to S14) of forming the power generating element 10 are the same as those in the manufacturing method of the battery 1 according to the first embodiment. In this embodiment, the outer peripheral edge of the laminate is cut to form the power generating element 10, and then the first extraction electrode 120 and the second extraction electrode 130 are formed (S18). Then, the first extraction electrode 120 is connected to the first current collector 12, and the second extraction electrode 130 is connected to the second current collector 15 (S20). In other words, the first extraction electrode 120 and the second extraction electrode 130 are connected to the power generating element 10 before the insulating layer 140 is formed. Note that, because lamination and sealing prevents the formation of the insulating layer 140, the connection in step S20 is merely alignment and temporary fixation.

[0146] After aligning the extraction electrodes and the current collectors, an insulating layer 140 is formed to cover the end faces and the outer peripheral edges of the upper and lower faces of the power generating element 10 (S16). Specifically, for example, a resin material is applied along the outer periphery of the power generating element 10 so as to cover the entire end faces of the power generating element 10, the exposed portion of the main surface 12a of the first current collector 12, and the exposed portion of the main surface 15a of the second current collector 15, and then cured to form the insulating layer 140.

[0147] In this way, by forming the insulating layer 140 after connecting the first extraction electrode 120 and the second extraction electrode 130 to the first current collector 12 and the second current collector 15, it is possible to prevent unevenness from being formed above and below the power generating element 10. Specifically, the upper surface of the first conductive member 121 and the upper surface of the insulating layer 140 can be made flush with each other, and the lower surface of the second conductive member 131 and the lower surface of the insulating layer 140 can be made flush with each other. This makes it easier for the confining pressure after lamination and sealing to be applied evenly to the power generating element 10.

[0148] Furthermore, in this embodiment, the first conductive member 121 does not protrude outward from the power generating element 10 in a plan view, except for the region 121a to which the first lead 22 is connected. Therefore, when a restraining pressure is applied to the power generating element 10, the protruding portion of the first conductive member 121 will not bend. The same applies to the second conductive member 131. Therefore, it is possible to prevent a short circuit between the positive electrode and the negative electrode.

[0149] (Embodiment 3) Next, a battery according to embodiment 3 will be described. In embodiment 3, the connection position of the second lead is mainly different from embodiments 1 and 2. The following description will focus on the differences with embodiments 1 and 2, and the description of the commonalities will be omitted or simplified.

[0150] Fig. 7 shows a plan view and a cross-sectional view of a battery 201 according to this embodiment. Specifically, Fig. 7(a) is a plan view of the battery 201 as seen from the positive side of the z-axis. Fig. 7(b) shows a cross section taken along line VIIb-VIIb in Fig. 7(a). Fig. 7(c) shows a cross section taken along line VIIc-VIIc in Fig. 7(a).

[0151] 7, the battery 201 includes a power generating element 10, a first extraction electrode 220, a second extraction electrode 230, an insulating layer 140, and a spacer 250. The power generating element 10 is the same as in the first and second embodiments, and therefore a description thereof will be omitted. The insulating layer 140 is substantially the same as in the second embodiment, although it has a different shape, and therefore a description thereof will be omitted.

[0152] As shown in Fig. 7, the first extraction electrode 220 includes a first conductive member 121 and a first lead 22. The first conductive member 121 and the first lead 22 are the same as those in the second embodiment, except that the connection position of the first lead 22 is different. As shown in (b) of Fig. 7, the first lead 22 is connected to the upper surface of the first conductive member 121. In other words, the first lead 22 is provided on the opposite side of the first conductive member 121 from the power generating element 10.

[0153] The second extraction electrode 230 includes a second conductive member 231 and a second lead 32. The second conductive member 231 differs from the second conductive member 131 according to the second embodiment in the direction in which it protrudes from the power generating element 10 in a plan view. Specifically, like the first conductive member 121, the second conductive member 231 protrudes from the power generating element 10 in the negative x-axis direction in a plan view. That is, in this embodiment, the first direction in which the first conductive member 121 protrudes and the second direction in which the second conductive member 231 protrudes are the same. In a plan view, a region 231a of the second conductive member 231 that does not overlap with the second current collector 15 overlaps with a region 121a of the first conductive member 121 that does not overlap with the first current collector 12. For example, the second conductive member 231 is identical in shape and position to the first conductive member 121 in a plan view.

[0154] The second lead 32 is the same as in the first and second embodiments except for its connection position and lead-out direction. The second lead 32 is connected to the lower surface of the second conductive member 231. In other words, the second lead 32 is provided on the opposite side of the second conductive member 231 from the power generating element 10. The second lead 32 is also led out in the negative direction of the y-axis. In this embodiment, the lead-out direction of the second lead 32 and the lead-out direction of the first lead 22 are opposite to each other. This makes it possible to ensure a distance between the second lead 32 and the first lead 22 and to prevent short circuits due to contact between the leads.

[0155] In this embodiment, a spacer 250 is provided in a portion sandwiched between the region 121a of the first conductive member 121 and the region 231a of the second conductive member 231. The spacer 250 is an insulating member. For example, the spacer 250 is formed using the same material as the insulating layer 140. That is, the spacer 250 may contain the same material as the insulating layer 140. In FIG. 7B, the spacer 250 and the insulating layer 140 are arranged apart from each other, but they may also be in contact with each other. That is, the spacer 250 may be provided integrally with the insulating layer 140. The provision of the spacer 250 can prevent the region 121a of the first conductive member 121 and the region 231a of the second conductive member 231 from coming into contact with each other and causing a short circuit.

[0156] The manufacturing method of the battery 201 is the same as the manufacturing method of the battery 101 according to the second embodiment shown in Fig. 6. The spacer 250 can be formed in the same process as the insulating layer 140. Note that the battery 201 does not necessarily have to include the spacer 250.

[0157] (Fourth embodiment) Next, a battery according to embodiment 4 will be described. In embodiment 4, the main difference from embodiments 1 to 3 is the position at which the second lead is taken out. The following description will focus on the differences from embodiments 1 to 3, and description of the commonalities will be omitted or simplified.

[0158] Figure 8 shows a plan view and a cross-sectional view of a battery 301 according to this embodiment. Specifically, (a) of Figure 8 is a plan view of the battery 301 as seen from the positive side of the z axis. (b) of Figure 8 shows a cross section taken along line VIIIb-VIIIb in (a) of Figure 8. (c) of Figure 8 shows a cross section taken along line VIIIc-VIIIc in (a) of Figure 8.

[0159] 8, the battery 301 includes a power generating element 10, a first extraction electrode 120, a second extraction electrode 330, and an insulating layer 140. The power generating element 10 is the same as in the first to third embodiments, and therefore a description thereof will be omitted. The insulating layer 140 is substantially the same as in the second and third embodiments, although it has a different shape, and therefore a description thereof will be omitted.

[0160] As shown in FIG. 8 , the second extraction electrode 330 includes a second conductive member 331 and a second lead 332. The second conductive member 331 differs from the second conductive member 131 according to the second embodiment in the direction in which it protrudes from the power generating element 10 in a plan view. Specifically, the second conductive member 331 protrudes from the power generating element 10 in the positive y-axis direction in a plan view. In other words, the second direction in which the second conductive member 331 protrudes is perpendicular to the first direction in which the first conductive member 121 protrudes. The protruding direction of the second conductive member 331 is the same as the drawing direction of the first lead 22. The second conductive member 331 has a region 331a that does not overlap with the second current collector 15. A second lead 332 is connected to the region 331a.

[0161] The second lead 332 is similar to the second lead 32 according to the first and second embodiments, except for its connection position and lead-out direction. In the example shown in FIG. 8(a), the shape of the second lead 332 in a plan view is a rectangle elongated in the x-axis direction, but this is not limiting. The second lead 332 may be elongated in the y-axis direction, similar to the first lead 22. In this embodiment, the lead-out direction of the second lead 332 and the lead-out direction of the first lead 22 are the same. This allows the second lead 332 and the first lead 22 to be drawn close to each other.

[0162] The protruding direction of the second conductive member 331 may be opposite to the extending direction of the first lead 22. That is, the second conductive member 331 may extend in the negative direction of the y-axis. In this case, the second lead 332 may be extended in the negative direction of the y-axis, or in the positive or negative direction of the x-axis. In this way, the extending direction of the leads can be appropriately adjusted depending on where the battery 301 is mounted. The battery 301 according to this embodiment allows for greater flexibility in lead arrangement.

[0163] The method for manufacturing the battery 301 is the same as the method for manufacturing the battery 101 according to the second embodiment shown in FIG.

[0164] (Embodiment 5) Next, a battery according to embodiment 5 will be described. In embodiment 5, the first conductive member and the second conductive member are each connected to the current collector via an adhesive, which is a major difference from embodiments 1 to 4. The following description will focus on the differences from embodiments 1 to 4, and the description of the commonalities will be omitted or simplified.

[0165] Fig. 9 shows a plan view and a cross-sectional view of a battery 401 according to this embodiment. Specifically, Fig. 9(a) is a plan view of the battery 401 as seen from the positive side of the z axis. Fig. 9(b) shows a cross section taken along line IXb-IXb in Fig. 9(a). Fig. 9(c) shows a cross section taken along line IXc-IXc in Fig. 9(a).

[0166] 9, the battery 401 includes a power generating element 10, a first extraction electrode 20, a second extraction electrode 30, an insulating layer 40, an adhesive layer 420, and an adhesive layer 430. The power generating element 10, the first extraction electrode 20, the second extraction electrode 30, and the insulating layer 40 are the same as those in the first embodiment, and therefore their description will be omitted.

[0167] The adhesive layer 420 is located between the first current collector 12 and the first conductive member 21. The adhesive layer 420 bonds the main surface 12a of the first current collector 12 and the first conductive member 21. In other words, the first conductive member 21 is connected to the main surface 12a of the first current collector 12 via the adhesive layer 420.

[0168] The adhesive layer 420 covers the entire main surface 12a. As shown in (b) and (c) of Figure 9, the adhesive layer 420 also covers the top surface of the insulating layer 40. The adhesive layer 420 may cover only the main surface 12a and not the top surface of the insulating layer 40. The adhesive layer 420 may also cover only a portion of the main surface 12a.

[0169] The adhesive layer 420 is electrically conductive. For example, the adhesive layer 420 is formed using a conductive resin material. Alternatively, the adhesive layer 420 may be a solder layer. The adhesive layer 420 may be a conductive carbon tape.

[0170] The adhesive layer 430 is located between the second current collector 15 and the second conductive member 31. The adhesive layer 430 bonds the main surface 15a of the second current collector 15 and the second conductive member 31. In other words, the second conductive member 31 is connected to the main surface 15a of the second current collector 15 via the adhesive layer 430.

[0171] The adhesive layer 430 covers the entire main surface 15a. As shown in (b) and (c) of Figure 9, the adhesive layer 430 also covers the lower surface of the insulating layer 40. The adhesive layer 430 may cover only the main surface 15a and not the lower surface of the insulating layer 40. The adhesive layer 430 may also cover only a portion of the main surface 15a.

[0172] The adhesive layer 430 is electrically conductive. For example, the adhesive layer 430 is formed using an electrically conductive resin material. Alternatively, the adhesive layer 430 may be a solder layer. The adhesive layer 430 may be an electrically conductive carbon tape. The adhesive layer 430 may be formed of the same material as the adhesive layer 420, or may be formed of a different material.

[0173] According to the battery 401 of this embodiment, the adhesive strength between the conductive member and the current collector can be increased, which can prevent the conductive member and the lead from being detached from the power generating element 10. This can improve the reliability of the battery 401.

[0174] The manufacturing method of the battery 401 is the same as the manufacturing method of the battery 1 according to the first embodiment shown in Fig. 4. In the step (S20) of connecting the first extraction electrode 20 and the second extraction electrode 30, an adhesive layer 420 is formed on at least one of the main surface 12a of the first current collector 12 and the first conductive member 21, and then the first current collector 12 and the first conductive member 21 are connected together. Similarly, an adhesive layer 430 is formed on at least one of the main surface 15a of the second current collector 15 and the second conductive member 31, and then the second current collector 15 and the second conductive member 31 are connected together.

[0175] The battery 401 may not include at least one of the adhesive layers 420 and 430. For example, one of the first extraction electrode 20 and the second extraction electrode 30 may be in contact with the first current collector 12 or the second current collector 15, as in the first embodiment, and may be fixed by confining pressure.

[0176] The battery 401 may also include a first extraction electrode 120 instead of the first extraction electrode 20. The battery 401 may also include a second extraction electrode 130, 230, or 330 instead of the second extraction electrode 30.

[0177] (Sixth embodiment) Next, a battery according to embodiment 6 will be described. The battery according to embodiment 6 differs from embodiments 1 to 5 mainly in that it includes a plurality of power generating elements connected in series. The following description will focus on the differences from embodiments 1 to 5, and description of commonalities will be omitted or simplified.

[0178] Fig. 10 shows a plan view and a cross-sectional view of a battery 501 according to this embodiment. Specifically, Fig. 10(a) is a plan view of the battery 501 as seen from the positive side of the z axis. Fig. 10(b) shows a cross section taken along line Xb-Xb in Fig. 10(a). Fig. 10(c) shows a cross section taken along line Xc-Xc in Fig. 10(a).

[0179] 10, the battery 501 includes a plurality of power generating elements 10, a first extraction electrode 120, a second extraction electrode 130, and an insulating layer 540. The first extraction electrode 120 and the second extraction electrode 130 are the same as those in the second embodiment, and therefore, description thereof will be omitted.

[0180] The plurality of power generating elements 10 are arranged side by side in the thickness direction of each layer. In the example shown in Fig. 10, three power generating elements 10 are stacked in order. The number of stacked power generating elements 10 may be two, four or more.

[0181] For example, among the multiple power generating elements 10, the power generating element 10 located at the top is defined as the first power generating element, and the power generating element 10 located at the middle is defined as the second power generating element. In this embodiment, the second electrode 14 of the first power generating element is connected to the first electrode 11 of the second power generating element. This electrically connects the first power generating element and the second power generating element in series.

[0182] In this embodiment, the multiple power generating elements 10 are stacked in order so that they are electrically connected in series and their current collectors are in contact with each other. Specifically, the positive electrode current collector of one power generating element 10 is connected to the negative electrode current collector of another power generating element 10. As shown in FIG. 10(c), the upper surface of the first current collector 12 of one power generating element 10 is in contact with the lower surface of the second current collector 15 of the power generating element 10 located above that one power generating element 10. Note that a conductive member may be interposed between the upper surface of the first current collector 12 and the lower surface of the second current collector 15.

[0183] The first extraction electrode 120 is connected to the main surface 12a of the first current collector 12 of the power generating element 10 located at the top among the multiple power generating elements 10. The second extraction electrode 130 is connected to the main surface 15a of the second current collector 15 of the power generating element 10 located at the bottom among the multiple power generating elements 10.

[0184] Similar to the insulating layer 140 according to the second embodiment, the insulating layer 540 is provided in a frame shape along the end face of the power generating element 10. In this embodiment, the insulating layer 540 is provided in a frame shape along the end face of each of the power generating elements 10. Furthermore, the insulating layer 540 covers the end of the main surface 12a of the first current collector 12 of the uppermost power generating element 10. Furthermore, the insulating layer 540 covers the end of the main surface 15a of the second current collector 15 of the lowermost power generating element 10.

[0185] As described above, the battery 501 according to this embodiment includes a plurality of power generating elements 10 connected in series, and therefore it is possible to realize a battery 501 that extracts a high voltage and has high reliability.

[0186] The manufacturing method of the battery 501 is the same as the manufacturing method of the battery 101 according to the second embodiment shown in FIG. 6. After the formation of the power generating elements 10 (S10 to S14) is performed multiple times in parallel or sequentially, the multiple power generating elements 10 are stacked. The cutting step (S14) may be performed collectively on the multiple power generating elements 10 after stacking. A first extraction electrode 120 and a second extraction electrode 130 are connected to the multiple power generating elements 10 that have been stacked and whose outer peripheral ends have been cut (S20). Thereafter, an insulating layer 540 is formed so as to cover the end faces of each of the multiple power generating elements 10 and the outer peripheral ends of the upper surface of the uppermost power generating element 10 and the lower surface of the lowermost power generating element 10 (S16).

[0187] The battery 501 may include a first extraction electrode 20 instead of the first extraction electrode 120. The battery 501 may include a second extraction electrode 30, 230, or 330 instead of the second extraction electrode 130. The battery 501 may also include at least one of adhesive layers 420 and 430.

[0188] (Embodiment 7) Next, a battery according to embodiment 7 will be described. The battery according to embodiment 7 differs from embodiments 1 to 6 mainly in that it includes a plurality of power generating elements connected in parallel. The following description will focus on the differences from embodiments 1 to 6, and description of commonalities will be omitted or simplified.

[0189] Fig. 11 shows a plan view and a cross-sectional view of a battery 601 according to this embodiment. Specifically, Fig. 11(a) is a plan view of the battery 601 as seen from the positive side of the z-axis. Fig. 11(b) shows a cross-section taken along line XIb-XIb in Fig. 11(a). Fig. 11(c) shows a cross-section taken along line XIc-XIc in Fig. 11(a).

[0190] 11, the battery 601 includes a plurality of power generating elements 10, a first extraction electrode 620, a second extraction electrode 130, and an insulating layer 540. The second extraction electrode 130 is the same as in the second embodiment, and therefore a description thereof will be omitted. The insulating layer 540 is substantially the same as in the sixth embodiment, although it has a different shape, and therefore a description thereof will be omitted.

[0191] The plurality of power generating elements 10 are arranged side by side in the thickness direction of each layer. In the example shown in Fig. 11, two power generating elements 10 are stacked in order. The number of stacked power generating elements 10 may be three or more.

[0192] For example, among the multiple power generating elements 10, the power generating element 10 located in the upper tier is defined as a first power generating element, and the power generating element 10 located in the lower tier is defined as a second power generating element. In this embodiment, the second electrode 14 of the first power generating element is connected to the second electrode 14 of the second power generating element. This electrically connects the first power generating element and the second power generating element in parallel.

[0193] In this embodiment, the multiple power generating elements 10 are stacked in order so as to be electrically connected in parallel. That is, the positive electrode current collectors of the multiple power generating elements 10 are connected to each other, or the negative electrode current collectors of the multiple power generating elements 10 are connected to each other. In the case of two power generating elements 10, the top and bottom layers are electrodes of the same polarity. Therefore, as shown in FIGS. 11(b) and 11(c), the first extraction electrode 620 includes two first conductive members 121 and 621.

[0194] The two first conductive members 121 and 621 are each connected to the main surface 12a of the first current collector 12 of each of the two power generating elements 10. The main surface 12a of the first current collector 12 of the upper power generating element 10 is the upper surface, and the main surface 12a of the first current collector 12 of the lower power generating element 10 is the lower surface. The two first conductive members 121 and 621 each protrude from the power generating element 10 in the negative direction of the x-axis in a plan view. A first lead 22 is connected between the two first conductive members 121 and 621. The first lead 22 may be connected only to the first conductive member 121, or the battery 601 may further include another first lead connected to the first conductive member 621. That is, the battery 601 may include two first extraction electrodes 120.

[0195] The second extraction electrode 130 is connected to the second current collectors 15 of the two power generating elements 10. That is, two second current collectors 15 are connected to the upper and lower surfaces of the second conductive member 131 of the second extraction electrode 130, respectively.

[0196] As described above, the battery 601 according to this embodiment includes a plurality of power generating elements 10 connected in parallel, so that the battery 601 can have a large capacity and is highly reliable.

[0197] The manufacturing method of the battery 601 is the same as the manufacturing method of the battery 101 according to the second embodiment shown in FIG. 6. Specifically, the formation of the power generating elements 10 (S10 to S14) is performed multiple times in parallel or sequentially, and then the multiple power generating elements 10 are stacked. At this time, two power generating elements 10 are stacked with the second extraction electrode 130 sandwiched between them. Then, the first extraction electrode 620 is connected (S20). Then, an insulating layer 540 is formed so as to cover the end faces of each of the multiple power generating elements 10 and the outer peripheral edges of the upper surface of the uppermost power generating element 10 and the lower surface of the lowermost power generating element 10 (S16).

[0198] The first extraction electrode 620 may include a first conductive member 21 instead of the first conductive member 121 or 621. The battery 601 may include a second extraction electrode 30, 230, or 330 instead of the second extraction electrode 130. The battery 601 may include at least one of the adhesive layers 420 and 430.

[0199] Furthermore, a plurality of batteries 601 shown in Fig. 11 may be stacked. Fig. 12 shows a plan view and a cross-sectional view of a battery 701 according to a modification of this embodiment. Specifically, Fig. 12(a) is a plan view of the battery 701 as viewed from the positive side of the z axis. Fig. 12(b) shows a cross section taken along line XIIb-XIIb in Fig. 12(a). Fig. 12(c) shows a cross section taken along line XIIc-XIIc in Fig. 12(a).

[0200] As shown in Fig. 12, the battery 701 has a stacked structure of two batteries 601 shown in Fig. 11. Specifically, the battery 701 includes two batteries 601 and an insulating sheet 750. The two batteries 601 are stacked with the insulating sheet 750 interposed therebetween.

[0201] Insulating sheet 750 is made of, for example, an insulating resin material and also functions as a buffer material. Insulating sheet 750 can alleviate stress caused by expansion due to heat generation in battery 701. Battery 701 does not necessarily have to include insulating sheet 750.

[0202] In this modification, the second lead 32 of the second extraction electrodes 130 of the two batteries 601 is shared. That is, the two second extraction electrodes 130 have the same configuration as the first extraction electrode 620. The two second leads 32 do not necessarily have to be shared.

[0203] As described above, battery 701 achieves a larger capacity.

[0204] (Variation) Next, modifications of the above-described embodiments will be described, specifically modifications of the extraction electrodes.

[0205] [Variation 1] 13 is a plan view of an extraction electrode 820 according to Modification 1. The extraction electrode 820 can be used as at least one of the first extraction electrode and the second extraction electrode according to each of the above-described embodiments.

[0206] 13, the extraction electrode 820 includes a conductive member 821 and a lead 822. The lead 822 is the same as the first lead 22 or the second lead 32 according to the first embodiment, and therefore a description thereof will be omitted.

[0207] The conductive member 821 differs from the first conductive member and the second conductive member according to each embodiment in that the sheet resistance is not uniform. Specifically, the sheet resistance of the conductive member 821 decreases as it is further away from the lead 822. In this modification, the lead 822 is provided at the end in the positive direction of the x-axis, and therefore the sheet resistance of the conductive member 821 decreases toward the negative direction of the x-axis.

[0208] Specifically, the conductive member 821 is provided with a plurality of through holes 823. The sheet resistance of the conductive member 821 is adjusted by at least one of the arrangement density and opening area of ​​the plurality of through holes 823. The plurality of through holes 823 shown in FIG. 13 are all the same size and have the same opening area. The arrangement density of the plurality of through holes 823 decreases as the distance from the lead 822 increases. That is, the number of the plurality of through holes 823 increases in a region closer to the lead 822, and decreases in a region farther from the lead 822. With this configuration, the sheet resistance increases in a region of the conductive member 821 close to the lead 822, and decreases in a region of the conductive member 821 farther from the lead 822. The plurality of through holes 823 can be formed by punching the flat plate-shaped conductive member 821.

[0209] If the sheet resistance of the conductive member 821 is uniform within the plane, the electric field tends to concentrate in the region close to the lead 822. In the portion where the electric field concentrates, the power generating element tends to deteriorate.

[0210] In contrast, in this modification, by increasing the sheet resistance in the region close to the lead 822, it is possible to make it difficult for the electric field to concentrate near the lead 822. In this way, it is possible to suppress local electric field concentration, thereby suppressing local deterioration of the battery, and therefore improving the reliability of the battery.

[0211] The opening areas of the plurality of through holes 823 may also be different. For example, the opening areas of the plurality of through holes 823 become smaller as they are further away from the lead 822. In this case as well, localized electric field concentration can be suppressed, thereby suppressing localized deterioration of the battery. Therefore, the reliability of the battery can be improved.

[0212] [Variation 2] Furthermore, the thickness of the conductive member may be varied as shown in Fig. 14. Fig. 14 shows a plan view and a cross-sectional view of an extraction electrode 920 according to Modification 2. Fig. 14(a) is a plan view of the extraction electrode 920 as seen from the negative side of the z axis. Fig. 14(b) shows a cross section taken along line XIVb-XIVb in Fig. 14(a).

[0213] As shown in FIG. 14, the extraction electrode 920 includes a conductive member 921 and a lead 822. As shown in FIG. 14(b), the thickness of the conductive member 921 increases with increasing distance from the lead 822. The conductive member 921 has main surfaces 921a and 921b. The main surface 921a is the surface that is connected to the current collector. The main surface 921b is the surface opposite to the main surface 921a and is inclined with respect to the main surface 921a. This allows the thickness of the conductive member 921 to change smoothly depending on the distance from the lead 822. The main surface 921a may be formed in a stepped shape.

[0214] The thicker the conductive member 921, the higher the sheet resistance, and the thinner the conductive member 921, the lower the sheet resistance. Therefore, the extraction electrode 920 shown in Fig. 14 can also suppress local electric field concentration, thereby suppressing local deterioration of the battery.

[0215] The conductive member 921 may have a plurality of through holes 823 formed therein.

[0216] (Other embodiments) Although the battery according to one or more aspects has been described based on the embodiments, the present disclosure is not limited to these embodiments. As long as it does not deviate from the gist of the present disclosure, various modifications conceivable by a person skilled in the art to the present embodiments and configurations constructed by combining components of different embodiments are also included within the scope of the present disclosure.

[0217] For example, in the above embodiment, an example was shown in which both the positive and negative electrode extracting electrodes of the battery include a conductive member and a lead, but only one of them may be provided. In other words, the battery does not need to include a second extracting electrode including a second conductive member and a second lead. For example, a tab as shown in FIGS. 1 and 2 may be provided on one of the current collectors of the positive and negative electrodes of the battery, and a second lead may be directly connected to the tab. Even in this case, the required cutting accuracy is lower than when tabs are provided on both of the two current collectors as shown in FIGS. 1 and 2, thereby improving the reliability of the battery.

[0218] Furthermore, various modifications, substitutions, additions, omissions, etc. can be made to the above-described embodiments within the scope of the claims or their equivalents. [Industrial Applicability]

[0219] The battery according to the present disclosure can be used, for example, as a secondary battery such as an all-solid-state battery used in various electronic devices or automobiles. [Explanation of symbols]

[0220] 1, 101, 201, 301, 401, 501, 601, 701 battery 10 Power generation elements 11 First electrode 12 First current collector 12a, 15a, 921a, 921b main surface 13 First active material layer 14 Second electrode 15 Second current collector 16 Second active material layer 17 Solid electrolyte layer 20, 120, 220, 620 First extraction electrode 21, 121, 621 First conductive member 21a, 31a, 121a, 131a, 231a, 331a area 22 First Lead 30, 130, 230, 330 Second extraction electrode 31, 131, 231, 331 Second conductive member 32, 332 Second Lead 40, 140, 540 Insulation layer 250 spacer 420, 430 adhesive layer 750 Insulation Sheet 820, 920 Extraction electrode 821, 921 Conductive material 822 leads 823 Through hole

Claims

1. a power generating element including a first electrode, a second electrode, and an electrolyte layer located between the first electrode and the second electrode; a first extraction electrode; Equipped with The first electrode is A first current collector; a first active material layer located between the first current collector and the electrolyte layer, The first extraction electrode is a first conductive member connected to a first surface of the first current collector opposite to the first active material layer; a first lead connected to the first conductive member; the first conductive member has a region that does not overlap with the first current collector in a plan view, the first lead is connected to the first conductive member only in the region; battery.

2. the first conductive member contacts the first surface of the first current collector; The battery of claim 1 .

3. an adhesive layer positioned between the first current collector and the first conductive member; the first conductive member is connected to the first surface of the first current collector via the adhesive layer; The battery of claim 1 .

4. The adhesive layer is electrically conductive. The battery of claim 3.

5. the first current collector and the first conductive member comprise the same material; The battery of any one of claims 1 to 4.

6. The thickness of the first conductive member is equal to or greater than the thickness of the first current collector. The battery of any one of claims 1 to 5.

7. The power generating element further includes an insulating layer provided in a frame shape along an end surface thereof. The battery of any one of claims 1 to 6.

8. The insulating layer further covers an edge of the first surface of the first current collector. The battery of claim 7.

9. the first conductive member covers the entire first surface of the first current collector in a plan view. The battery of any one of claims 1 to 7.

10. A power generating element including a first electrode, a second electrode, and an electrolyte layer located between the first electrode and the second electrode; a first extraction electrode; Equipped with The first electrode is A first current collector; a first active material layer located between the first current collector and the electrolyte layer, The first extraction electrode is a first conductive member connected to a first surface of the first current collector opposite to the first active material layer; a first lead connected to the first conductive member; the sheet resistance of the first conductive member decreases as the first conductive member is further away from the first lead; battery.

11. The first conductive member is provided with a plurality of through holes, At least one of the arrangement density and the opening area of ​​the plurality of through holes decreases with increasing distance from the first lead. The battery of claim 10.

12. The thickness of the first conductive member increases as it moves away from the first lead.

12. The battery according to claim 10 or 11.

13. Further provided with a second extraction electrode, The second electrode is A second current collector; a second active material layer located between the second current collector and the electrolyte layer, The second extraction electrode is a second conductive member connected to a second surface of the second current collector opposite to the second active material layer; a second lead connected to the second conductive member; 13. The battery of any one of claims 1 to 12.

14. the first conductive member protrudes in a first direction from the power generating element in a plan view, the second conductive member protrudes in a second direction from the power generating element in a plan view, the first lead is connected to the protruding portion of the first conductive member; The second lead is connected to the protruding portion of the second conductive member.

14. The battery of claim 13.

15. The first direction and the second direction are opposite directions.

15. The battery of claim 14.

16. The first direction and the second direction are the same direction.

15. The battery of claim 14.

17. The first direction and the second direction are perpendicular to each other.

15. The battery of claim 14.

18. The electrolyte layer contains a solid electrolyte having lithium ion conductivity.

18. The battery of any one of claims 1 to 17.

19. A plurality of the power generating elements are provided, the first extraction electrode is connected to the first current collector of a first power generating element that is one of the plurality of power generating elements, a second power generating element which is one of the plurality of power generating elements is stacked on the second electrode side of the first power generating element; 19. The battery of any one of claims 1 to 18.

20. the second electrode of the first power generating element is connected to the first electrode of the second power generating element; 20. The battery of claim 19.

21. the second electrode of the first power generating element is connected to the second electrode of the second power generating element; 20. The battery of claim 19.

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