Laminated battery

Abstract

A stacked battery comprises a plurality of stacked battery cells and a collector lead. Each of the plurality of battery cells comprises a positive electrode collector, a solid electrolyte layer, a positive electrode active material layer disposed between the positive electrode collector and the solid electrolyte layer, a negative electrode collector, and a negative electrode active material layer disposed between the positive electrode active material layer and the negative electrode collector. The plurality of battery cells comprises a first battery cell and a second battery cell adjacent to each other. The first battery cell has a surface opposite to the second battery cell. The surface opposite to the second battery cell comprises an exposed surface that is not in contact with the second battery cell. When viewed from the stacking direction of the plurality of battery cells, at least a portion of the exposed surface does not overlap with the second battery cell. The collector lead is connected to the exposed surface.

Description

Technical Field

[0001] The present disclosure relates to laminated batteries. Background Art

[0002] Patent Document 1 discloses a battery in which stacked batteries have lead wires of different lengths.

[0003] Patent Document 2 discloses a bipolar laminated battery including unit cells and internal electrode layers alternately laminated with the unit cells.

[0004] Patent Document 3 discloses a bipolar secondary battery in which positive electrode bodies and negative electrode bodies of different sizes are alternately stacked with solid electrolyte layers disposed therebetween.

[0005] Prior Art Literature

[0006] Patent Literature

[0007] Patent Document 1: Japanese Patent Application Publication No. 2013-97907

[0008] Patent Document 2: Japanese Patent Application Publication No. 2014-116156

[0009] Patent Document 3: Japanese Patent Application Publication No. 2015-153663 Summary of the invention

[0010] In the prior art, it is desired to improve the reliability and battery capacity density of stacked batteries.

[0011] Therefore, the present disclosure provides a laminated battery having improved reliability and battery capacity density.

[0012] A stacked battery in one embodiment of the present disclosure comprises a plurality of stacked battery cells and a current collector lead. Each of the plurality of battery cells comprises a positive electrode collector, a solid electrolyte layer, a positive electrode active material layer disposed between the positive electrode collector and the solid electrolyte layer, a negative electrode collector, and a negative electrode active material layer disposed between the positive electrode active material layer and the negative electrode collector. The plurality of battery cells comprises a first battery cell and a second battery cell adjacent to each other. The first battery cell has a surface opposite to the second battery cell. The surface opposite to the second battery cell is a negative electrode active material layer disposed between the positive electrode active material layer and the negative electrode collector. The plurality of battery cells comprises a first battery cell and a second battery cell adjacent to each other. The first battery cell has a surface opposite to the second battery cell. The surface opposite to the second battery cell comprises an exposed surface that is not in contact with the second battery cell. When viewed from the stacking direction of the plurality of battery cells, at least a portion of the exposed surface does not overlap with the second battery cell. The current collecting lead is connected to the exposed surface.

[0013] According to the present disclosure, the reliability and battery capacity density of a stacked battery can be improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1A It is a plan view showing a schematic structure of a laminated battery in the first embodiment.

[0015] Figure 1B This is a cross-sectional view showing a schematic structure of a laminated battery in the first embodiment.

[0016] Figure 2A This is a plan view showing a schematic configuration of a battery cell in Modification 1 of Embodiment 1.

[0017] Figure 2B This is a cross-sectional view showing a schematic structure of a laminated battery in Modification 1 of Embodiment 1.

[0018] Figure 3A This is a perspective view showing a schematic configuration of a laminated battery in Modification 2 of Embodiment 1.

[0019] Figure 3B It is a plan view of a battery cell constituting a laminated battery in a second variation of the first embodiment.

[0020] Figure 4 This is a cross-sectional view showing a schematic configuration of a laminated battery in Modification 3 of Embodiment 1.

[0021] Figure 5 This is a cross-sectional view showing a schematic structure of a laminated battery in Modification 4 of Embodiment 1.

[0022] Figure 6 This is a cross-sectional view showing an example of a schematic configuration of a laminated battery in the second embodiment.

[0023] Figure 7 This is a cross-sectional view showing another example of the schematic structure of the laminated battery in the second embodiment.

[0024] Figure 8 This is a cross-sectional view showing another example of the schematic structure of the laminated battery in the second embodiment.

[0025] Fig. 9 This is a cross-sectional view showing a schematic structure of a laminated battery in the third embodiment. DETAILED DESCRIPTION

[0026] (Overview of the present disclosure)

[0027] A stacked battery in one embodiment of the present disclosure comprises a plurality of stacked battery cells and a current collector lead. Each of the plurality of battery cells comprises a positive electrode collector, a solid electrolyte layer, a positive electrode active material layer disposed between the positive electrode collector and the solid electrolyte layer, a negative electrode collector, and a negative electrode active material layer disposed between the positive electrode active material layer and the negative electrode collector. The plurality of battery cells comprises a first battery cell and a second battery cell adjacent to each other. The first battery cell has a surface opposite to the second battery cell. The surface opposite to the second battery cell is a negative electrode active material layer disposed between the positive electrode active material layer and the negative electrode collector. The plurality of battery cells comprises a first battery cell and a second battery cell adjacent to each other. The first battery cell has a surface opposite to the second battery cell. The surface opposite to the second battery cell comprises an exposed surface that is not in contact with the second battery cell. When viewed from the stacking direction of the plurality of battery cells, at least a portion of the exposed surface does not overlap with the second battery cell. The current collecting lead is connected to the exposed surface.

[0028] Thus, the collector lead is connected to the first battery cell using the exposed surface that is not in contact with the adjacent second battery cell. Since the first battery cell has an exposed surface, a space where no battery cell exists is formed on the exposed surface, so the effective volume that functions as a battery is reduced in the apparent volume of the stacked battery. However, the collector lead is connected without increasing the size in the stacking direction caused by the insertion of the lead layer for connecting the collector lead. In the case of a stacked battery constituting a flat battery cell, the increase in the size in the stacking direction has a great influence on the increase in the volume of the stacked battery. Therefore, by connecting the collector lead on the exposed surface, the increase in the size in the stacking direction caused by the layer that does not contribute to the battery capacity can be suppressed, so the battery capacity density of the stacked battery is improved. In addition, in the negative electrode collector or the positive electrode collector, the collector lead is connected not on the end face substantially parallel to the stacking direction but on the stacking surface intersecting the stacking direction, so it is easy to increase the area of ​​the connection between the collector lead and the negative electrode collector or the positive electrode collector. Therefore, the connection of the current collecting leads on the laminated battery becomes firmer, and the reliability of the laminated battery is improved.

[0029] Furthermore, when viewed from the stacking direction of the plurality of battery cells, the entire exposed surface may not overlap with the second battery cell. In addition, the side surface of the second battery cell may be inclined. In this case, when viewed from the stacking direction of the plurality of battery cells, the exposed surface may include a portion that does not overlap with the second battery cell and a portion that overlaps with a portion or all of the inclined side surface of the second battery cell.

[0030] Furthermore, for example, the thickness of the current collecting lead in the stacking direction at a position overlapping with the exposed surface when viewed in the stacking direction may be thinner than the thickness of the second battery cell in the stacking direction.

[0031] Thus, the third battery cell other than the first and second battery cells can be stacked on the upper side of the current collecting lead connected to the exposed surface without contacting the current collecting lead. That is, when the current collecting lead and the third battery cell overlap when viewed from the stacking direction, the current collecting lead and the third battery cell do not contact. Therefore, the stacking shape of the stacked battery is not easily restricted, and a stacked battery with a stacking shape having a better volume efficiency can be formed.

[0032] In addition, for example, the thickness of the collector lead in the stacking direction at the position overlapping the exposed surface when viewed from the stacking direction may be thicker than the thickness of the positive electrode collector in the second battery cell or the thickness of the negative electrode collector in the stacking direction.

[0033] Thus, when charging and discharging with a large current is performed, since the thickness of the current collecting lead is thicker than the thickness of the current collector, the allowable current becomes larger, and the degradation of the battery characteristics can be reduced.

[0034] In addition, for example, the plurality of battery cells may be electrically connected in parallel or in series.

[0035] Thus, in the case of a parallel-connected stacked battery, stable charging and discharging can be performed using the current collecting lead. In addition, in the case of a series-stacked battery, charging and discharging can be performed safely while monitoring the voltage of each stacked battery cell using the current collecting lead.

[0036] In addition, for example, the position of the side surface of the first battery cell and the position of the side surface of the second battery cell may be offset in a direction perpendicular to the stacking direction.

[0037] Thus, the exposed surface can be formed simply by shifting the stacking positions of the battery cells, so that the stacked battery can be manufactured simply.

[0038] In addition, for example, it may be that: the multiple battery cells each have a first side surface perpendicular to the stacking direction and a second side surface in a direction opposite to the first side surface, and among the multiple battery cells, battery cells arranged in a staggered direction in the direction of the first side surface and battery cells arranged in a staggered direction in the direction of the second side surface are arranged alternately.

[0039] As a result, the battery cells are stacked in a direction in which the misalignment of the positions of the battery cells caused by stacking is eliminated, so the increase in the apparent volume of the stacked battery caused by forming the exposed surface is reduced. In other words, the area of ​​the stacked battery as a whole when viewed from the stacking direction can be reduced. Therefore, the battery capacity density of the stacked battery is further improved.

[0040] In addition, for example, the plurality of battery cells may have the same shape.

[0041] This eliminates the need to separately shape each battery cell, and enables easy manufacture of a laminated battery.

[0042] In addition, for example, it may be that: the second battery cell has a recessed portion whose end portion is recessed inward when viewed from the stacking direction, and at least a portion of the inner side of the concave shape of the recess overlaps with at least a portion of the exposed surface of the first battery cell when viewed from the stacking direction.

[0043] Thus, an exposed surface can be formed on the surface of the first battery cell that is opposite to the second battery cell, which overlaps with the inner side of the recessed portion of the second battery cell when viewed from the stacking direction. Therefore, when the recessed portion is formed in accordance with the shape of the current collecting lead, the reduction in effective volume caused by the formation of the exposed surface can be reduced, so that the battery capacity density of the stacked battery is further improved.

[0044] In addition, for example, when viewed from the stacking direction, the positions of the end portions of the plurality of battery cells other than the recessed portions may be the same.

[0045] Thus, the first and second battery cells adjacent to each other are structured so that only the portions overlapping the inner side of the recessed portion do not contact each other when viewed from the stacking direction, thereby forming an exposed surface. Therefore, the reduction in effective volume caused by the formation of the exposed surface can be reduced, and the battery capacity density of the stacked battery is further improved.

[0046] In addition, for example, the exposed surface of the first battery cell and the second battery cell may be connected via a joining portion formed of a conductive material.

[0047] As a result, the mechanical and electrical connections between the stacked battery cells become stronger, and the connection impedance between the battery cells becomes smaller, thereby achieving a stacked battery with suppressed heat generation and improved high-current characteristics.

[0048] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings.

[0049] Furthermore, the embodiments described below are all general or specific examples. The numerical values, shapes, materials, components, configuration positions and connection forms of components, steps, and the order of steps shown in the following embodiments are examples and do not limit the present disclosure. In addition, the components in the following embodiments that are not recorded in the independent claims are described as arbitrary components.

[0050] In addition, each figure is a schematic diagram and may not be a strict illustration. Therefore, for example, the scales in each figure may not be the same. In addition, in each figure, the same symbols are marked for substantially the same structure, and repeated descriptions are omitted or simplified.

[0051] In addition, in this specification, terms such as parallel that indicate the relationship between elements, terms such as rectangle that indicate the shape of elements, and numerical ranges are not expressions with strict meanings, but also include substantially equivalent ranges, such as expressions with differences of several percent.

[0052] In addition, in this specification and the accompanying drawings, the x-axis, y-axis and z-axis represent the three axes of the three-dimensional orthogonal coordinate system. In each embodiment, the z-axis direction is set to the stacking direction of the stacked battery. In addition, the "thickness" in this specification refers to the length of the battery cell, the collector lead, the collector and each layer in the stacking direction. In addition, in this specification, "top view" means the situation of viewing the stacked battery along the stacking direction of the battery cell in the stacked battery. In addition, the "side" in this specification is a surface that intersects with the direction perpendicular to the stacking direction of the stacked battery. The "side" can be, for example, a surface substantially parallel to the stacking direction of the stacked battery. In addition, the "stacking surface" in this specification is a surface that intersects with the stacking direction. The "stacking surface" can be, for example, a surface substantially perpendicular to the stacking direction of the stacked battery.

[0053] In addition, in this specification, the terms "upper" and "lower" in the structure of the stacked battery do not refer to the upper direction (vertically above) and the lower direction (vertically below) in absolute spatial recognition, but are used as terms defined by relative positional relationships based on the stacking order in the stacked structure. In addition, the terms "upper" and "lower" are not only applicable to the case where two components are arranged at a distance from each other and there is another component between the two components, but also to the case where two components are arranged in close contact with each other.

[0054] (Implementation Method 1)

[0055] Figure 1A and Figure 1B 1 is a diagram showing a schematic configuration of a stacked battery 1000 in Embodiment 1. Specifically, Figure 1A 1 is a plan view schematically showing the structure of the laminated battery 1000 , and the planar shape of each component of the laminated battery 1000 when the laminated battery 1000 is viewed from above in the stacking direction is indicated by solid lines or dotted lines. Figure 1B is a cross-sectional view showing a schematic structure of a stacked battery 1000, showing Figure 1A The cross section at the position indicated by line II.

[0056] like Figure 1A and Figure 1B As shown, the laminated battery 1000 in the first embodiment has a structure in which a plurality of battery cells 2000 are laminated, and the plurality of battery cells 2000 are electrically connected in parallel to form the laminated battery 1000. In addition, the laminated battery 1000 includes a current collecting lead 500.

[0057] Each battery cell 2000 includes a negative electrode current collector 210, a negative electrode active material layer 110, a solid electrolyte layer 130, a positive electrode current collector 220, and a positive electrode active material layer 120. The negative electrode current collector 210 and the positive electrode current collector 220 may be collectively referred to as simply "current collector".

[0058] The negative electrode active material layer 110 and the positive electrode current collector 220 face each other with the solid electrolyte layer 130 interposed therebetween.

[0059] Each battery cell 2000 has a structure in which a positive electrode collector 220, a positive electrode active material layer 120, a solid electrolyte layer 130, a negative electrode active material layer 110, and a negative electrode collector 210 are stacked in sequence when viewed from either the upper or lower direction of the stacking direction (z-axis direction) of the battery cell 2000. The negative electrode collector 210, the negative electrode active material layer 110, the solid electrolyte layer 130, the positive electrode collector 220, and the positive electrode active material layer 120 are stacked in an overlapping manner when viewed from the stacking direction, and each is rectangular in a plan view. Among the plurality of battery cells 2000, two adjacent battery cells 2000 are stacked with the electrodes inverted in direction. That is, the stacked battery 1000 has a structure in which a plurality of battery cells 2000 are stacked in a manner in which the positive electrode collectors 220 of two adjacent battery cells 2000 or the negative electrode collectors 210 are in contact with each other. Thus, the stacked battery 1000 becomes a parallel stacked battery in which a plurality of battery cells 2000 are electrically connected in parallel.

[0060] In the stacked battery 1000, the thickness and width of the positive electrode collector 220, the positive electrode active material layer 120, the solid electrolyte layer 130, the negative electrode active material layer 110 and the negative electrode collector 210 contained in the multiple battery cells 2000 are the same among the multiple battery cells 2000, but can also be different among the multiple battery cells 2000.

[0061] The negative electrode active material layer 110 contains, for example, a negative electrode active material as an electrode material and is disposed opposite to the positive electrode active material layer 120 .

[0062] Graphite, metal lithium, and the like can be used as the negative electrode active material contained in the negative electrode active material layer 110. Various materials capable of desorbing and absorbing ions of lithium (Li) or magnesium (Mg) can be used as the material of the negative electrode active material.

[0063] In addition, as the material contained in the negative electrode active material layer 110, a solid electrolyte such as an inorganic solid electrolyte may also be used. As the inorganic solid electrolyte, for example, a sulfide solid electrolyte or an oxide solid electrolyte may be used. As the sulfide solid electrolyte, for example, a mixture of lithium sulfide (Li2S) and phosphorus pentasulfide (P2S5) may be used. In addition, as the material contained in the negative electrode active material layer 110, a conductive material such as acetylene black, carbon black, graphite, carbon fiber or a bonding adhesive such as polyvinylidene fluoride may also be used.

[0064] The negative electrode active material layer 110 can be produced, for example, by applying a slurry coating obtained by kneading the materials contained in the negative electrode active material layer 110 with a solvent onto the surface of the negative electrode collector 210 and drying the coating. In order to increase the density of the negative electrode active material layer 110, the negative electrode plate including the negative electrode active material layer 110 and the negative electrode collector 210 may be pressed after drying. The thickness of the negative electrode active material layer 110 is, for example, not less than 5 μm and not more than 300 μm, but is not limited thereto.

[0065] The positive electrode active material layer 120 is a layer containing a positive electrode material such as an active material. The positive electrode material is a material constituting a counter electrode of the negative electrode material. The positive electrode active material layer 120 contains, for example, a positive electrode active material.

[0066] As the positive electrode active material contained in the positive electrode active material layer 120, for example, lithium cobalt oxide composite oxide (LCO), lithium nickel oxide composite oxide (LNO), lithium manganese oxide composite oxide (LMO), lithium-manganese-nickel composite oxide (LMNO), lithium-manganese-cobalt composite oxide (LMCO), lithium-nickel-cobalt composite oxide (LNCO), lithium-nickel-manganese-cobalt composite oxide (LNMCO) and the like can be used.

[0067] As the material of the positive electrode active material, various materials that can desorb and absorb ions such as Li and Mg can be used.

[0068] In addition, as the material contained in the positive electrode active material layer 120, solid electrolytes such as inorganic solid electrolytes can also be used. As inorganic solid electrolytes, sulfide solid electrolytes or oxide solid electrolytes can be used. As sulfide solid electrolytes, for example, a mixture of lithium sulfide (Li2S) and phosphorus pentasulfide (P2S5) can be used. The surface of the positive electrode active material can also be covered with a solid electrolyte. In addition, as the material contained in the positive electrode active material layer 120, conductive materials such as acetylene black, carbon black, graphite, carbon fiber, or bonding adhesives such as polyvinylidene fluoride can also be used.

[0069] The positive electrode active material layer 120 can be produced, for example, by applying a slurry coating obtained by kneading the materials contained in the positive electrode active material layer 120 with a solvent onto the surface of the positive electrode collector 220 and drying it. In order to increase the density of the positive electrode active material layer 120, the positive electrode plate including the positive electrode active material layer 120 and the positive electrode collector 220 may be pressed after drying. The thickness of the positive electrode active material layer 120 is, for example, not less than 5 μm and not more than 300 μm, but is not limited thereto.

[0070] The solid electrolyte layer 130 is disposed between the negative electrode active material layer 110 and the positive electrode active material layer 120. The solid electrolyte layer 130 is in contact with each of the negative electrode active material layer 110 and the positive electrode active material layer 120. The solid electrolyte layer 130 is a layer containing an electrolyte material. As the electrolyte material, a generally known electrolyte for a battery can be used. The thickness of the solid electrolyte layer 130 can be 5 μm or more and 300 μm or less, and can be 5 μm or more and 100 μm or less.

[0071] Solid electrolyte layer 130 may include a solid electrolyte. Battery cell 2000 may be, for example, an all-solid battery.

[0072] As a solid electrolyte, a solid electrolyte such as an inorganic solid electrolyte can be used. As an inorganic solid electrolyte, a sulfide solid electrolyte, an oxide solid electrolyte, or a halide solid electrolyte can be used. As a sulfide solid electrolyte, for example, a mixture of lithium sulfide (Li2S) and phosphorus pentasulfide (P2S5) can be used. Furthermore, the solid electrolyte layer 130 may also contain a bonding adhesive such as polyvinylidene fluoride in addition to the electrolyte material.

[0073] The solid electrolyte layer 130 can be produced, for example, by applying a slurry coating prepared by kneading the materials containing the solid electrolyte layer 130 with a solvent onto the negative electrode active material layer 110 formed on the negative electrode collector 210 and / or onto the positive electrode active material layer 120 formed on the positive electrode collector 220 and drying the coating. Alternatively, the solid electrolyte layer 130 can be formed by coating and drying on a carrier film such as a PET film, and then transferred and laminated onto the negative electrode active material layer 110 formed on the negative electrode collector 210 and / or onto the positive electrode active material layer 120 formed on the positive electrode collector 220.

[0074] In the battery cell 2000 in the first embodiment, the negative electrode active material layer 110, the positive electrode active material layer 120, and the solid electrolyte layer 130 are maintained in a parallel flat plate shape. This can suppress the occurrence of cracks or collapse caused by bending. Furthermore, the negative electrode active material layer 110, the positive electrode active material layer 120, and the solid electrolyte layer 130 can also be smoothly bent together.

[0075] The negative electrode collector 210 and the positive electrode collector 220 are each a conductive member. The negative electrode collector 210 and the positive electrode collector 220 may be, for example, a conductive thin film. As a material constituting the negative electrode collector 210 and the positive electrode collector 220, metals such as stainless steel (SUS), aluminum (Al), and copper (Cu) may be used.

[0076] The negative electrode current collector 210 is arranged in contact with the negative electrode active material layer 110. As the negative electrode current collector 210, for example, a metal foil such as SUS foil or Cu foil can be used. The thickness of the negative electrode current collector 210 is, for example, 5 μm or more and 100 μm or less, but is not limited thereto. Furthermore, the negative electrode current collector 210 may also include a current collector layer as a layer containing a conductive material, for example, in a portion in contact with the negative electrode active material layer 110.

[0077] The positive electrode current collector 220 is arranged in contact with the positive electrode active material layer 120. As the positive electrode current collector 220, for example, a metal foil such as SUS foil or Al foil can be used. The thickness of the positive electrode current collector 220 is, for example, 5 μm or more and 100 μm or less, but is not limited thereto. Furthermore, the positive electrode current collector 220 may also include a current collector layer as a layer containing a conductive material, for example, in a portion in contact with the positive electrode active material layer 120.

[0078] The battery cell 2000 can be manufactured, for example, by stacking the above-mentioned solid electrolyte layer 130 between the negative electrode active material layer 110 and the positive electrode active material layer 120. Thus, a battery cell 2000 having a structure in which the positive electrode collector 220, the positive electrode active material layer 120, the solid electrolyte layer 130, the negative electrode active material layer 110, and the negative electrode collector 210 are stacked in sequence can be obtained. In addition, the battery cell 2000 may be pressurized from the outside of the positive electrode collector 220 and the negative electrode collector 210 after the stacking of the layers.

[0079] like Figure 1A and Figure 1BAs shown, one of the two adjacent battery cells 2000 included in the plurality of battery cells 2000 (hereinafter referred to as the first battery cell) 2000 has an exposed surface 300 that does not contact the second battery cell 2000 on the surface facing the other battery cell (hereinafter referred to as the second battery cell) 2000. Specifically, the negative electrode collector 210 of each battery cell 2000 other than the battery cell 2000 in the lowermost layer and the uppermost layer has an exposed surface 300 that does not overlap with the battery cell 2000 adjacent to the battery cell 2000 when viewed from the stacking direction. In addition, the positive electrode collector 220 of each battery cell 2000 has an exposed surface 300 that does not overlap with the battery cell 2000 adjacent to the battery cell 2000 when viewed from the stacking direction. The stacked battery 1000 in the first embodiment has a structure in which a portion of the side surface of each battery cell 2000 is offset and stacked when viewed from the stacking direction. Specifically, the positions of the side surfaces of two adjacent battery cells 2000 are staggered in the x-axis direction perpendicular to the stacking direction. In addition, the positions of the side surfaces of the battery cells 2000 are alternately staggered in the positive direction and the negative direction of the x-axis perpendicular to the stacking direction according to the stacking order. By stacking in such an alternating staggered manner, the area of ​​the stacked battery as a whole viewed from the stacking direction can be reduced.

[0080] When stacking, for example, 6 battery cells 2000, the Figure 1B The battery cells 2000 are stacked in a zigzag (Z-shaped) manner as shown in the figure, or as described later. Figure 2A and Figure 2B As shown, the battery cells 2000 are stacked in order while being shifted in the same direction along the x-axis.

[0081] In addition, when stacking, for example, 6 battery cells, it is also possible to Figure 3A and Figure 3B As shown, battery cells having notches formed in a portion of the battery cells are stacked.

[0082] The number of stacked battery cells 2000 is not limited to six, and any number of battery cells 2000 can be stacked.

[0083] The offset manner of the side surface of the battery cell 2000 or the shape of the notch is not limited to the above-mentioned example.

[0084] Figure 1B 1 is a schematic cross-sectional view showing an example of a portion of a stacked battery 1000 formed by stacking a plurality of battery cells 2000 with their side surfaces partially offset when viewed in the stacking direction in various ways.

[0085] like Figure 1A and Figure 1BAs shown, a plurality of battery cells 2000 having the same shape are stacked with their side surfaces partially offset when viewed from the stacking direction, thereby forming an exposed surface 300. In addition, a stacking space 400 where no battery cell 2000 is present is formed on the exposed surface 300.

[0086] The stacking space 400 is used to connect the current collector lead 500 to the exposed surface 300 of the negative electrode current collector 210 or the positive electrode current collector 220 of each battery cell 2000. The current collector lead 500 is a conductor used for charging and discharging, monitoring the voltage between terminals, etc., and is mainly used for charging and discharging in the stacked battery 1000 in which a plurality of battery cells 2000 are electrically connected in parallel. Figure 1A and Figure 1B In the embodiment, the shape of the current collecting lead 500 is a flat plate, but the shape of the current collecting lead 500 is not particularly limited and may be a cylindrical shape or other shapes. The thickness of the current collecting lead 500 is thinner than the thickness of the battery cell 2000 adjacent to the exposed surface 300 side of the battery cell 2000 to which the current collecting lead 500 is connected. Figure 1B As shown, even if the battery cells 2000 are stacked in a zigzag pattern, the current collecting lead 500 is connected to the exposed surface 300 without being hindered by the battery cells 2000 stacked above or below the exposed surface 300. In addition, the thickness of the current collecting lead 500 is thicker than the positive electrode collector 220 and the negative electrode collector 210. As a result, the allowable current of the current collecting lead 500 becomes larger, and the degradation of the battery characteristics can be reduced. Furthermore, the thickness of the current collecting lead 500 is the length of the current collecting lead 500 in the stacking direction.

[0087] As a material constituting the current collecting lead 500, metals such as nickel, stainless steel, aluminum, and copper can be used. The connection method of the current collecting lead 500 is not particularly limited, and methods such as bonding and welding can be used. The current collecting lead 500 can be connected to the current collector by a conductive adhesive or adhesive tape. In order to prevent short circuits, the surface of the portion of the current collecting lead 500 that is not connected to the current collector can be insulated.

[0088] According to the connection method of the collector lead 500 using the stacking space 400 on the exposed surface 300, there is an advantage that the collector lead 500 can be connected without the increase in the dimension in the stacking direction caused by the insertion of the lead layer for connecting the collector lead which does not contribute to the battery capacity. In the stacking plane in-plane direction, a space (space) equivalent to the stacking space 400 on the exposed surface 300 is required. That is, the stacking space 400 that does not function as a battery is formed by the battery cell 2000 having the exposed surface 300, so that the effective volume of the stacked battery 1000 is reduced. However, especially if the stacked battery becomes a large-format size, it becomes important to ensure the battery capacity density of the stacked battery that the increase in the dimension in the stacking direction caused by the layer that does not contribute to the battery capacity is small, and the effect of ensuring a small space in the stacking plane in-plane direction on the battery capacity density is smaller than the effect of the increase in the dimension in the stacking direction on the battery capacity density. The smaller the thickness in the stacking direction is compared with the side length in the stacking plane in-plane direction, the more effective the stacked battery 1000 in this embodiment is. Since the current collecting lead 500 thicker than the current collector can be directly connected to the current collector without increasing the size in the stacking direction, a high-capacity parallel stacked battery with low impedance loss and heat generation during charge and discharge and excellent large current characteristics can be obtained.

[0089] In such Figure 1A and Figure 1B When stacking the battery cells 2000 with their side surfaces staggered in the x-axis direction as in the stacked battery 1000 shown, the width of the exposed surface 300 in the x-axis direction, which is the short side direction of the exposed surface 300, may be 0.2 mm or more, for example, from the viewpoint of ensuring an area for connecting the current collecting lead 500. In addition, from the viewpoint of ensuring battery capacity, the width of the exposed surface 300 may be, for example, 5% or less, or 1% or less relative to the width of the battery cell 2000 in the x-axis direction.

[0090] The stacked battery 1000 is manufactured, for example, by the following method: (1) the current collecting lead 500 is connected to the exposed surface 300 of each battery cell 2000 in advance to form a Figure 1A and Figure 1B In the stacked structure shown in FIG. 1 , each battery cell 2000 connected with the current collecting lead 500 is stacked with the battery cells 2000 staggered in the x-axis direction. In addition, the stacked battery 1000 can also be manufactured by the following method: (2) Figure 1A and Figure 1BIn the stacked structure shown in FIG. 1 , a plurality of battery cells 2000 are stacked while being staggered in the x-axis direction. After all the battery cells 2000 are stacked, the current collecting lead 500 is connected to the exposed surface 300. Alternatively, the stacked battery 1000 may be manufactured by the following method: (3) repeatedly performing the steps of stacking the battery cells 2000 while being staggered in the x-axis direction and connecting the current collecting lead 500 to the exposed surface 300 of the stacked battery cells 2000, thereby forming Figure 1A and Figure 1B The stacked structure shown.

[0091] Regarding the above-mentioned methods (1) to (3), an appropriate method may be selected according to the target stacking structure, or the above-mentioned methods (1) to (3) may be combined to manufacture the stacked battery 1000. For example, in the case where the stacking structure after the battery cells 2000 are stacked is a position where it is difficult to connect the collector lead 500 on the exposed surface 300, the above-mentioned method (1) is used for manufacturing, and in the case where the stacking structure after the battery cells 2000 are stacked is a position where it is easy to connect the collector lead 500 on the exposed surface 300, the above-mentioned method (2) or (3) is used for manufacturing. Figure 1A and Figure 1B In the manufacture of the stacked battery 1000 shown, since the battery cells 2000 exist above or below the exposed surface 300 to which the current collecting leads 500 are connected, it is difficult to connect the current collecting leads 500 after all the battery cells 2000 are stacked. Therefore, the above-mentioned method (1) is preferably used.

[0092] The laminated battery 1000 may be enclosed in a sealing case. As the sealing case, a laminate bag, a metal can, a resin case, etc. may be used, but it is not limited thereto. By sealing, it is possible to suppress the laminated battery 1000 from being deteriorated by moisture.

[0093] (Variation Example)

[0094] Hereinafter, a plurality of modified examples of Embodiment 1 will be described. In the following description of the plurality of modified examples, the description will be mainly focused on the differences from Embodiment 1 or the differences between the modified examples, and the description of the common points will be omitted or simplified.

[0095] [Modification 1]

[0096] Figure 2A and Figure 2B 1 is a diagram showing a schematic configuration of a stacked battery 1100 in a first variation of the first embodiment. Specifically, Figure 2A 1 is a plan view schematically showing the structure of the stacked battery 1100 , and the planar shape of each component of the stacked battery 1100 when the stacked battery 1100 is viewed from above in the stacking direction is indicated by solid lines or dotted lines. Figure 2Bis a cross-sectional view showing a schematic structure of a stacked battery 1100, showing Figure 2A The cross section at the position indicated by line II-II.

[0097] like Figure 2A and Figure 2B As shown, a stacked battery 1100 in the first modification of the first embodiment includes a plurality of battery cells 2000 which are electrically connected in parallel to form the stacked battery 1100. The stacked battery 1100 is different from the stacked battery 1000 in the first embodiment in that the plurality of battery cells 2000 are stacked in a staggered manner in the same direction.

[0098] Each battery cell 2000 has a structure in which a positive electrode collector 220 , a positive electrode active material layer 120 , a solid electrolyte layer 130 , a negative electrode active material layer 110 and a negative electrode collector 210 are stacked in sequence when viewed from either the upper or lower direction of the stacking direction (z-axis direction) of the battery cell 2000 .

[0099] like Figure 2A and Figure 2B As shown, the first battery cell 2000 among two adjacent battery cells 2000 included in the plurality of battery cells 2000 has an exposed surface 300 that is not in contact with the second battery cell 2000 in the surface opposite to the second battery cell 2000. The exposed surface 300 is formed by stacking the plurality of battery cells 2000 with a portion of the side surfaces thereof offset. Specifically, the structure is such that the positions of the side surfaces of the two adjacent battery cells 2000 are offset in a direction perpendicular to the stacking direction and the battery cells are stacked. The structure is such that the positions of the side surfaces of the plurality of battery cells 2000 are offset in the same x-axis direction perpendicular to the stacking direction in accordance with the stacking order and the battery cells are stacked.

[0100] The current collector lead 500 is connected to the exposed surface 300 of the negative electrode current collector 210 and the positive electrode current collector 220. According to the connection method of the current collector lead 500 using the exposed surface 300, there is an advantage similar to the first embodiment that the current collector lead 500 can be connected without increasing the dimension in the stacking direction due to the insertion of a lead layer for connecting the current collector lead which does not contribute to the battery capacity.

[0101] In addition, since the stacked battery 1100 does not have a battery cell 2000 above or below the exposed surface 300, it is easy to increase the thickness of the current collecting lead 500. Figure 2B In the laminated battery 1100 shown, the collector lead 500 is thinner than the battery cell 2000, but the collector lead 500 may be thicker than the battery cell 2000. By thickening the collector lead 500, the impedance loss and heat generation during charge and discharge can be further reduced.

[0102] In addition, since the stacked battery 1100 does not have a battery cell 2000 above or below the exposed surface 300, it is easy to connect the current collecting lead 500 even after all the battery cells 2000 are stacked. Therefore, the stacked battery 1100 can be easily manufactured even by the method (2) or (3) among the methods for manufacturing the stacked battery described in the first embodiment.

[0103] [Modification 2]

[0104] Figure 3A and Figure 3B 1 is a diagram showing a schematic configuration of a stacked battery 1200 in a second variation of the first embodiment. Specifically, Figure 3A It is a perspective view showing a schematic structure of a laminated battery 1200. The laminated battery 1200 includes battery cells 2100a to 2100e. Figure 3B It is a plan view of each of the battery cells 2100a to 2100e constituting the laminated battery 1200, and the battery cells above the battery cells 2100a to 2100e are omitted.

[0105] Although in Figure 3A Although omitted in the illustration, the battery cells 2100a to 2100e have the same structure as the battery cell 2000 in embodiment 1, in which the positive electrode collector 220, the positive electrode active material layer 120, the solid electrolyte layer 130, the negative electrode active material layer 110 and the negative electrode collector 210 are stacked in sequence when viewed from either the upper or lower direction of the stacking direction (z-axis direction) of the battery cell.

[0106] like Figure 3A As shown, the stacked battery 1200 has a structure in which battery cells 2100a to 2100e are stacked. Figure 3A and Figure 3B As shown in (b) to (d) of FIG. 1 , the battery cells 2100b to 2100d are provided with recessed portions 450 in which the ends of the battery cells 2100b to 2100d are recessed inward when viewed from the stacking direction. Figure 3B As shown in (a) and (e) of FIG. 1 , no recess 450 is formed on the battery cell 2100a and the battery cell 2100e. Figure 3BAs shown in (b) to (d) of FIG. 1 , the positions of the recesses 450 of the battery cells 2100b to 2100d are different. When viewed from the stacking direction, there are battery cells adjacent to the battery cells 2100b to 2100d on the inner sides of the recesses 450 of the battery cells 2100b to 2100d. In other words, by forming the recesses 450 on the battery cells 2100b to 2100d, it is possible to form exposed surfaces 300 that do not contact the battery cells 2100b to 2100d on the battery cells adjacent to the battery cells 2100b to 2100d.

[0107] When the battery cells 2100 a to 2100 e are viewed in the stacking direction, the positions of the ends thereof other than the recessed portion 450 are the same.

[0108] The collector lead 500 is connected to the exposed surface 300 using the space inside the recess 450. According to the connection method of the collector lead 500 using the space inside the recess 450 on the exposed surface 300, there is an advantage that the collector lead 500 can be connected without increasing the size in the stacking direction due to the insertion of a lead layer for connecting the collector lead which does not contribute to the battery capacity. In the stacking plane direction, a space equivalent to the space inside the recess 450 is required, but as long as there is a space for connecting the collector lead 500, it is sufficient, and the battery capacity density of the stacked battery can be easily ensured.

[0109] The battery cells 2100b to 2100d having the recessed portion 450 formed therein can be manufactured, for example, by preparing a battery cell without the recessed portion 450 and cutting the battery cell in the stacking direction using a knife, a drill, a laser, or the like. There is no particular limitation on the cut shape of the recessed portion 450 as viewed from the stacking direction, but Figure 3B As shown, the cut shape of the inner side of the recessed portion 450 viewed from the stacking direction is preferably a curved shape from the viewpoint of suppressing the defect of each layer.

[0110] [Variation 3]

[0111] Figure 4 This is a cross-sectional view showing a schematic structure of a laminated battery 1300 in Modification 3 of Embodiment 1.

[0112] like Figure 4 As shown, the stacked battery 1300 in the third variant of the first embodiment has a plurality of battery cells 2000, and the plurality of battery cells 2000 are electrically connected in series to form the stacked battery 1300. The stacked battery 1300 is different from the stacked battery 1000 in the first embodiment in that the plurality of battery cells 2000 are electrically connected in series. The stacked shape of the plurality of battery cells 2000 in the stacked battery 1300 is the same as that of the stacked battery 1000 in the first embodiment, and the top view is similar to the stacked battery 1000 in the first embodiment. Figure 1AThe stacked battery 1000 shown has the same shape.

[0113] Each battery cell 2000 includes a negative electrode current collector 210 , a negative electrode active material layer 110 , a solid electrolyte layer 130 , a positive electrode current collector 220 , and a positive electrode active material layer 120 .

[0114] The battery cell 2000 has a structure in which a positive electrode collector 220, a positive electrode active material layer 120, a solid electrolyte layer 130, a negative electrode active material layer 110, and a negative electrode collector 210 are sequentially stacked along the stacking direction (z-axis direction) of the battery cell 2000. In the stacked battery 1300, two adjacent battery cells 2000 are stacked in such a manner that the positive electrode collector 220 of the first battery cell 2000 and the negative electrode collector 210 of the second battery cell 2000 are in contact. Thus, the stacked battery 1300 becomes a series stacked battery in which a plurality of battery cells 2000 are electrically connected in series.

[0115] As in the case of the first embodiment, Figure 4 1 is a schematic cross-sectional view showing an example of a portion of a stacked battery 1300 formed by stacking a plurality of battery cells 2000 with their side surfaces partially offset in various ways.

[0116] like Figure 4 As shown, the first battery cell 2000 among two adjacent battery cells 2000 included in the plurality of battery cells 2000 has an exposed surface 300 that does not contact the second battery cell 2000 in the surface opposite to the second battery cell 2000. Specifically, the negative electrode collector 210 of each battery cell 2000 other than the battery cell 2000 in the bottom layer has an exposed surface 300 that does not overlap with the battery cell 2000 adjacent to the battery cell 2000 when viewed from the stacking direction. In addition, the positive electrode collector 220 of each battery cell 2000 other than the battery cell 2000 in the top layer has an exposed surface 300 that does not overlap with the battery cell 2000 adjacent to the battery cell 2000 when viewed from the stacking direction.

[0117] The exposed surface 300 is formed by stacking the plurality of battery cells 2000 with their side surfaces partially offset when viewed from the stacking direction. In addition, a stacking space 400 where no battery cell 2000 is present is formed on the exposed surface 300.

[0118] The collector lead 500 is connected to the exposed surface 300 of the negative electrode collector 210 or the positive electrode collector 220 of each battery cell 2000 using the stacking space 400. In the stacked battery 1300 in which a plurality of battery cells 2000 are electrically connected in series, the collector lead 500 connected to the exposed surface 300 is mainly used to monitor the voltage between the terminals.

[0119] According to the connection method of the current collector lead 500 using the stacking space 400 on the exposed surface 300, the following advantages are obtained in the same manner as in the first embodiment: the current collector lead 500 can be connected without the increase in the dimension in the stacking direction caused by the insertion of the lead layer for connecting the current collector lead which does not contribute to the battery capacity. In the stacking plane in-plane direction, a space equivalent to the stacking space 400 on the exposed surface 300 is required. That is, since the battery cell 2000 has the exposed surface 300, the stacking space 400 which does not function as a battery is formed, and thus the effective volume of the stacked battery 1000 is reduced. However, especially if the stacked battery has a large format size, it becomes important to reduce the increase in the dimension in the stacking direction caused by the layer which does not contribute to the battery capacity, and the effect of ensuring a small space in the stacking plane in-plane direction on the battery capacity density is smaller than the effect of the increase in the dimension in the stacking direction on the battery capacity density. The smaller the thickness in the stacking direction is compared with the side length in the stacking plane in-plane direction, the more effective the stacked battery 1300 in this modified example is. Since the inter-terminal voltage of the battery cell 2000 can be monitored without increasing the dimensions in the stacking direction, a high-capacity series stacked battery with excellent safety can be obtained.

[0120] [Variation 4]

[0121] Figure 5 This is a cross-sectional view showing a schematic structure of a laminated battery 1400 in a fourth modification of the first embodiment.

[0122] like Figure 5 As shown, the stacked battery 1400 in the fourth variation of the first embodiment has a plurality of battery cells 2000, and the plurality of battery cells 2000 are electrically connected to form the stacked battery 1400. The stacked battery 1400 is different from the stacked battery 1000 in the first embodiment in that the plurality of battery cells 2000 are electrically connected in a combination of parallel connection and series connection. The stacked shape of the plurality of battery cells 2000 in the stacked battery 1400 is the same as that of the stacked battery 1000 in the first embodiment, and the top view is similar to the stacked battery 1000 in the first embodiment. Figure 1A The stacked battery 1000 shown has the same shape.

[0123] Each battery cell 2000 includes a negative electrode current collector 210 , a negative electrode active material layer 110 , a solid electrolyte layer 130 , a positive electrode current collector 220 , and a positive electrode active material layer 120 .

[0124] As in the case of the first embodiment, Figure 5 1 is a schematic cross-sectional view showing an example of a portion of a stacked battery 1400 formed by stacking a plurality of battery cells 2000 with their end faces partially offset in various ways.

[0125] exist Figure 5In the embodiment, a plurality of battery cells 2000 are electrically connected by combining parallel connection and series connection. That is, two adjacent battery cells 2000 that are connected in series are stacked in such a manner that the positive electrode collector 220 of the first battery cell 2000 and the negative electrode collector 210 of the second battery cell 2000 are in contact with each other, and two adjacent battery cells 2000 that are connected in parallel are stacked in such a manner that the positive electrode collectors 220 or the negative electrode collectors 210 are in contact with each other.

[0126] like Figure 5 As shown, the first battery cell 2000 among two adjacent battery cells 2000 included in the plurality of battery cells 2000 has an exposed surface 300 that does not contact the second battery cell 2000 in the surface facing the second battery cell 2000. Specifically, the negative electrode collector 210 of each battery cell 2000 other than the battery cells 2000 in the lowermost layer and the uppermost layer has an exposed surface 300 that does not overlap with the battery cell 2000 adjacent to the battery cell 2000 when viewed from the stacking direction. In addition, the positive electrode collector 220 of each battery cell 2000 has an exposed surface 300 that does not overlap with the battery cell 2000 adjacent to the battery cell 2000 when viewed from the stacking direction.

[0127] The exposed surface 300 is formed by stacking the plurality of battery cells 2000 with their side surfaces partially offset when viewed from the stacking direction. In addition, a stacking space 400 where no battery cell 2000 is present is formed on the exposed surface 300.

[0128] The stacking space 400 is utilized to connect the current collecting lead 500 to the exposed surface 300 of the negative electrode current collector 210 or the positive electrode current collector 220 of each battery cell 2000 .

[0129] According to the connection method of the collector lead 500 using the stacking space 400 on the exposed surface 300, there is an advantage that the collector lead 500 can be connected without the increase in the dimension in the stacking direction caused by the insertion of the lead layer for connecting the collector lead which does not contribute to the battery capacity. In the stacking plane in-plane direction, a space equivalent to the stacking space 400 on the exposed surface 300 is required. That is, since the battery cell 2000 has the exposed surface 300, the stacking space 400 that does not function as a battery is formed, and thus the effective volume of the stacked battery 1000 is reduced. However, especially if the stacked battery becomes a large-format size, it becomes important to ensure the battery capacity density of the stacked battery that the increase in the dimension in the stacking direction caused by the layer that does not contribute to the battery capacity is small, and the effect of ensuring a small space in the stacking plane in-plane direction on the battery capacity density is smaller than the effect of the increase in the dimension in the stacking direction on the battery capacity density. The smaller the thickness in the stacking direction is compared with the side length in the stacking plane in-plane direction, the more effective the stacked battery 1400 in this modified example is. Since the current collecting lead 500 having a thickness greater than that of the current collector can be directly connected to the current collector, an excellent high-capacity laminated battery combining parallel connection and series connection can be obtained which has excellent large current characteristics and can monitor the voltage between the terminals of the battery cell.

[0130] (Implementation Method 2)

[0131] Hereinafter, Embodiment 2 will be described. In the following description, differences from Embodiment 1 and each modification example described above will be mainly described, and description of common points will be appropriately omitted or simplified.

[0132] Each stacked battery shown in the above-mentioned first embodiment and each modified example may further be provided with a sealing material 700. Figure 6 , Figure 7 and Figure 8 An example of a stacked battery in which a sealing material 700 is disposed is shown. Figure 6 , Figure 7 and Figure 8 1 and 2 are cross-sectional views showing schematic configurations of stacked batteries 1500 to 1700 in Embodiment 2. Specifically, Figure 6 FIG. 1 shows a stacked battery 1500 in which a sealing material 700 is disposed on the outer periphery of the stacked battery 1000 in Embodiment 1. Figure 7 FIG. 1 shows a stacked battery 1600 in which a sealing material 700 is arranged on the periphery of the stacked battery 1300 in the third variation of the first embodiment. Figure 8 2 shows a stacked battery 1700 in which a sealing material 700 is arranged on the outer periphery of the stacked battery 1400 in the fourth modification of the first embodiment.

[0133] The sealing material 700 is formed of, for example, an electrically insulating material and also functions as a spacer for maintaining the stacking space 400 .

[0134] For example, the sealing material 700 is a material including the first material. For example, the sealing material 700 may be a material including the first material as a main component. For example, the sealing material 700 may be a material consisting of only the first material.

[0135] As the first material, a generally known sealing material of a battery such as a sealing agent can be used. As the first material, for example, a resin material can be used. Furthermore, the first material can be a material that is insulating and does not have ion conductivity. For example, the first material can be at least one of epoxy resin, acrylic resin, polyimide resin, and silsesquioxane.

[0136] The sealing material 700 may include a particulate metal oxide material. As the metal oxide material, silicon oxide, aluminum oxide, titanium oxide, zinc oxide, cerium oxide, iron oxide, tungsten oxide, zirconium oxide, calcium oxide, zeolite, glass, etc. may be used. For example, the sealing material 700 may be formed using a resin material in which a plurality of particles composed of a metal oxide material are dispersed.

[0137] The particle size of the metal oxide material may be smaller than the distance between the negative electrode current collector 210 and the positive electrode current collector 220. The particle shape of the metal oxide material may be a perfect circle (sphere), an ellipsoid, a rod, or the like.

[0138] By configuring the sealing material 700, the reliability of the stacked battery can be improved in terms of improving mechanical strength, preventing short circuits, and preventing moisture. In addition, since the sealing material 700 enters the stacking space 400, the sealing material 700 is difficult to peel off compared to a case where there is no stacking space 400, resulting in a firmly sealed stacked battery.

[0139] (Implementation method 3)

[0140] Hereinafter, Embodiment 3 will be described. In the following description, differences from Embodiment 1, Embodiment 2, and each modified example described above will be mainly described, and description of common points will be appropriately omitted or simplified.

[0141] Fig. 9 1 is a cross-sectional view showing a schematic structure of a stacked battery 1800 in Embodiment 3. Specifically, Fig. 9 2 shows a laminated battery 1800 in which a joint portion 800 is formed in a laminated battery having the same structure as the laminated battery 1000 in the first embodiment.

[0142] like Fig. 9As shown, the exposed surface 300 of the first battery cell 2000 and the second battery cell 2000 of two adjacent battery cells 2000 are connected by a joint 800 made of a conductive material. Specifically, among the two adjacent battery cells 2000, the exposed surface 300 of the first battery cell 2000 and the negative electrode collector 210 or the positive electrode collector 220 of the second battery cell 2000 are connected by the joint 800.

[0143] The joint 800 can be formed by joining the exposed surface 300 and the current collector using a conductive material. As the conductive material constituting the joint 800, there is no particular limitation as long as it is a material with high conductivity, and metals such as silver, nickel, stainless steel, aluminum, and copper can be used. In addition, as the conductive material, a conductive adhesive can also be used. The joint 800 can be formed, for example, by welding the exposed surface 300 and the current collector connected by the joint 800 with the aid of the above-mentioned conductive material, or by melting a part of the exposed surface 300 and the current collector connected by the joint 800.

[0144] In the laminated battery 1800 , the mechanical and electrical connections between the battery cells 2000 are more firmly formed due to the formation of the joints 800 , and the connection impedance between the battery cells 2000 is reduced, thereby achieving effects such as suppressing heat generation and improving large current characteristics.

[0145] (Other Embodiments)

[0146] The stacked battery involved in the present disclosure is described above based on the embodiments, but the present disclosure is not limited to these embodiments. As long as it does not depart from the main purpose of the present disclosure, the embodiments obtained by various deformations thought of by those skilled in the art and other methods constructed by combining some of the constituent elements in the embodiments are also included in the scope of the present disclosure.

[0147] In addition, various changes, substitutions, additions, omissions, etc. can be made to the above-mentioned embodiments within the scope of the claims or their equivalents.

[0148] For example, in the above-mentioned embodiment, the stacked battery forms an exposed surface by stacking a plurality of battery cells staggered in the x-axis direction, but the invention is not limited thereto. In the stacked battery, a plurality of battery cells may be stacked staggered in the y-axis direction, or a structure in which a plurality of battery cells are stacked staggered in the x-axis direction and a structure in which a plurality of battery cells are stacked staggered in the y-axis direction may be mixed. In addition, an exposed surface may be formed by stacking battery cells having different widths in the x-axis direction or the y-axis direction.

[0149] In the above embodiment, all of the plurality of battery cells have exposed surfaces, but the present invention is not limited thereto and the shape and stacking position of the battery cells may be adjusted according to the target connection position of the current collecting lead to include battery cells without exposed surfaces.

[0150] In addition, in the above-mentioned embodiment, the current collecting lead is formed only on the exposed surface, but the present invention is not limited thereto. In order to improve reliability, an insulating layer made of an insulating material such as resin may be provided on the surface of the current collecting lead opposite to the surface connected to the exposed surface. In addition, an insulating layer made of an insulating material such as resin may be provided on the exposed surface other than the connection portion with the current collecting lead or on the exposed surface to which the current collecting lead is not connected.

[0151] In addition, in the above embodiment, the shape of the battery cell in plan view is a rectangle, but the present invention is not limited thereto and the shape of the battery cell in plan view may be a circle, an ellipse or a polygon.

[0152] In the above embodiment, the thickness of the current collecting lead is constant, but the present invention is not limited thereto. The thickness of the current collecting lead may be varied by increasing the thickness of the current collecting lead in the portion other than the exposed surface, depending on the purpose.

[0153] In addition, in the above-mentioned embodiment, the current collecting lead is connected to the exposed surface of each battery cell constituting the stacked battery, but the present invention is not limited thereto. The stacked battery may also include a battery cell in which the current collecting lead is not connected to the exposed surface. For example, the exposed surface to which the current collecting lead is not connected can also be effectively used as a surface for making terminals etc. contact from the outside, a display surface for identification marks, etc.

[0154] Industrial Applicability

[0155] The laminated battery of the present disclosure can be used as a battery for electronic devices, electric appliances, electric vehicles, and the like.

[0156] Description of Reference Numerals

[0157] 110 Negative electrode active material layer

[0158] 120 positive electrode active material layer

[0159] 130 Solid electrolyte layer

[0160] 210 Negative electrode collector

[0161] 220 positive electrode collector

[0162] 300 Show up

[0163] 400 Cascading Space

[0164] 450 recess

[0165] 500 Collector Lead

[0166] 700 Sealing material

[0167] 800 Joint

[0168] 1000, 1100, 1200, 1300, 1400, 1500, 1600, 1700, 1800 stacked batteries

[0169] 2000, 2100a, 2100b, 2100c, 2100d, 2100e battery cells

Claims

1. A stacked battery comprising: A plurality of stacked battery cells; and Collector lead, Each of the plurality of battery cells includes a positive electrode collector, a solid electrolyte layer, a positive electrode active material layer disposed between the positive electrode collector and the solid electrolyte layer, a negative electrode collector, and a negative electrode active material layer disposed between the positive electrode active material layer and the negative electrode collector. The plurality of battery cells include a first battery cell and a second battery cell adjacent to each other, The first battery cell has a surface facing the second battery cell, The surface facing the second battery cell includes an exposed surface that is not in contact with the second battery cell, When viewed from the stacking direction of the plurality of battery cells, at least a portion of the exposed surface does not overlap with the second battery cell. The current collecting lead is connected to the exposed surface, The first battery cell and the second battery cell are electrically connected via the surface.

2. The stacked battery according to claim 1, The thickness of the current collecting lead in the stacking direction at a position overlapping the exposed surface when viewed in the stacking direction is thinner than the thickness of the second battery cell in the stacking direction.

3. The laminated battery according to claim 1 or 2, The thickness of the current collecting lead in the stacking direction at a position overlapping the exposed surface when viewed in the stacking direction is thicker than the thickness of the positive electrode current collector or the negative electrode current collector of the second battery cell in the stacking direction.

4. The stacked battery according to claim 1 or 2, The plurality of battery cells are electrically connected in parallel or in series.

5. The stacked battery according to claim 1 or 2, The position of the side surface of the first battery cell and the position of the side surface of the second battery cell are offset in a direction perpendicular to the stacking direction.

6. The stacked battery according to claim 1 or 2, The plurality of battery cells have the same shape.

7. The stacked battery according to claim 1 or 2, The second battery cell has a recessed portion whose end portion is recessed inward when viewed from the stacking direction. When viewed from the stacking direction, at least a portion of the inner side of the concave shape of the concave portion overlaps with at least a portion of the exposed surface of the first battery cell.

8. The stacked battery according to claim 7, The positions of the ends of the plurality of battery cells other than the recessed portions are the same when viewed in the stacking direction.

9. The stacked battery according to any one of claims 1, 2 and 8, The exposed surface is a surface of the positive electrode current collector or a surface of the negative electrode current collector included in the first battery cell.

10. The stacked battery according to any one of claims 1, 2 and 8, Each of the plurality of battery cells has a structure in which the positive electrode collector, the positive electrode active material layer, the solid electrolyte layer, the negative electrode active material layer, and the negative electrode collector are stacked in this order.

11. The laminated battery according to any one of claims 1, 2 and 8, When viewed from a direction perpendicular to the stacking direction, a portion of the current collecting lead on the exposed surface overlaps with the second battery cell.

Images