Bipolar battery and manufacturing method therefor

Abstract

A bipolar battery according to an embodiment of the present disclosure comprises: a frame, which partitions a plurality of regions while extending in a first direction and a second direction; and unit cells each arranged in the plurality of regions and each including a first electrode, a solid electrolyte and a second electrode stacked in a third direction, wherein neighboring unit cells in the first direction are arranged such that the first electrodes and the second electrodes are alternately positioned at both end parts in the third direction, neighboring unit cells in the first direction are electrically connected in series to each other, the first electrodes of the unit cells positioned at one end part in the first direction are electrically connected to each other in the second direction, second electrodes of the unit cells positioned at the other end part in the first direction are electrically connected to each other in the second direction, and the first direction, the second direction and the third direction can be perpendicular to each other.

Description

Bipolar battery and method for manufacturing the same

[0001] Embodiments of the present disclosure relate to a bipolar battery and a method for manufacturing the same.

[0002] With the recent rapid proliferation of information and communication devices such as personal computers, video cameras, and mobile phones, the development of batteries to power them has become increasingly important. Furthermore, the automotive industry and other sectors are also working on developing high-power, high-capacity batteries for electric and hybrid vehicles. Currently, among various types of batteries, lithium batteries are attracting attention due to their high energy density.

[0003] Current commercially available lithium batteries use electrolytes containing flammable organic solvents. Therefore, safety devices to suppress temperature rise during short-circuiting, as well as structural and material improvements to prevent short-circuiting, are required. In contrast, all-solid-state lithium batteries, which replace the electrolyte with a solid electrolyte layer and thus eliminate the use of flammable organic solvents, simplify safety devices and are expected to offer superior manufacturing costs and productivity.

[0004] Current commercially available lithium batteries use electrolytes containing flammable organic solvents. Therefore, safety devices to suppress temperature rise during short-circuiting, as well as structural and material improvements to prevent short-circuiting, are required. In contrast, all-solid-state lithium batteries, which replace the electrolyte with a solid electrolyte layer and thus eliminate the use of flammable organic solvents, simplify safety devices and are expected to offer superior manufacturing costs and productivity.

[0005] Embodiments of the present disclosure provide a bipolar battery and a method for manufacturing the same, which can freely improve output voltage and energy density.

[0006] A bipolar battery according to an embodiment of the present disclosure can be widely applied in green technology fields such as electric vehicles, battery charging stations, and solar and wind power generation using batteries.

[0007] According to one embodiment of the present disclosure, a bipolar battery comprises: a frame extending in a first direction and a second direction and defining a plurality of regions; and unit cells each disposed in the plurality of regions, each including a first electrode, a solid electrolyte, and a second electrode, which are stacked in a third direction; wherein unit cells adjacent in the first direction are respectively disposed such that first electrodes and second electrodes are alternately positioned at opposite ends in the third direction, the unit cells adjacent in the first direction are electrically connected to each other in series, the first electrodes of the unit cells located at one end in the first direction are electrically connected to each other along the second direction, and the second electrodes of the unit cells located at the other end in the first direction are electrically connected to each other along the second direction, and the first direction, the second direction, and the third direction may be orthogonal to each other.

[0008] In one embodiment, the bipolar battery may further include a first electrode tab electrically connecting first electrodes of unit cells located at one end in the first direction; and a second electrode tab electrically connecting second electrodes of unit cells located at the other end in the first direction.

[0009] In one embodiment, the length of the solid electrolyte in the first direction may be longer than that of the first electrode and the second electrode.

[0010] In one embodiment, the height of the frame in the third direction may be less than or equal to the height of the unit cells in the third direction.

[0011] In one embodiment, the unit cells adjacent in the first direction may have the first electrode and the second electrode at the upper end electrically connected to each other, or the first electrode and the second electrode at the lower end electrically connected to each other.

[0012] In one embodiment, the bipolar battery may further include an upper cover disposed at one end of the unit cells and the frame in the third direction, and including an insulating material.

[0013] In one embodiment, the frame may include a lower plate on which the unit cells are arranged on one side in the third direction; and a first partition wall portion extending from the lower plate in the third direction, partitioning the plurality of regions and insulating the unit cells from each other in the first direction and the second direction.

[0014] In one embodiment, the upper cover may include an upper plate disposed at one end of the unit cells in the third direction; and a second partition wall portion extending from the upper plate in the third direction and connected to the first partition wall portion.

[0015] In one embodiment, within the unit cell, the first electrode and the second electrode are each positioned at opposite ends in the third direction, and the solid electrolyte may be positioned between the first electrode and the second electrode.

[0016] In one embodiment, the unit cell may include at least one bipolar electrode between the first electrode and the second electrode, the bipolar electrode including a bipolar current collector, a first active material layer formed on one surface of the bipolar current collector, and a second active material layer formed on the other surface of the bipolar current collector.

[0017] In one embodiment, the frame may include an insulating material.

[0018] In one embodiment, the frame may include an elastic material.

[0019] In one embodiment, the frame may include one or more materials selected from the group consisting of polyurethane, natural rubber, spandex, isobutylene isoprene rubber (IIR), fluoroelastomer, elastomer, ethylene-propylene rubber (EPR), styrene-butadiene rubber (SBR), chloroprene, elastomer, rubber epichlorohydrin, nylon, terpene, isoprene rubber, polybutadiene, nitrile rubber, thermoplastic elastomer, silicone rubber, ethylene-propylene-diene rubber (EPDM), ethylene vinyl acetate (EVA), halogenated butyl rubber, neoprene, and copolymers thereof.

[0020] In one embodiment, the bipolar battery may further include a fixing member to which the frame and the upper cover are joined and fixed.

[0021] In one embodiment, the frame and the upper cover can be opened and closed relative to each other with the fixing member as an axis.

[0022] A method for manufacturing a bipolar battery according to one embodiment of the present disclosure includes the steps of: arranging unit cells in each of a plurality of regions defined by frames extending in a first direction and a second direction; connecting unit cells adjacent in the first direction in series; and electrically connecting first electrodes of unit cells positioned at one end in the first direction to each other along the second direction, and electrically connecting second electrodes of unit cells positioned at the other end in the first direction to each other along the second direction; wherein the unit cells include a first electrode, a solid electrolyte, and a second electrode stacked in a third direction, and the unit cells adjacent in the first direction are respectively arranged such that the first electrodes and the second electrodes are alternately positioned at opposite ends in the third direction, and the first direction, the second direction, and the third direction may be orthogonal to each other.

[0023] In one embodiment, the step of connecting the adjacent unit cells in series in the first direction may include the step of electrically connecting the first electrode and the second electrode located at the upper portions of the adjacent unit cells in the first direction to each other; or the step of electrically connecting the first electrode and the second electrode located at the lower portions of the adjacent unit cells in the first direction to each other.

[0024] In one embodiment, the method for manufacturing the bipolar battery may further include a step of combining an upper cover including an insulating material to one end of the unit cells and the frame in the third direction.

[0025] In one embodiment, the step of arranging the unit cells may include: arranging a conductor on the frame; and arranging the unit cells in the plurality of regions such that one end of the unit cells in the third direction is in contact with the conductor.

[0026] In one embodiment, the step of arranging the unit cells may further include the step of insulating a portion of the conductor that does not come into contact with the unit cells.

[0027] According to embodiments of the present disclosure, a bipolar battery and a method for manufacturing the same can be provided, which can freely improve output voltage and energy density.

[0028] FIG. 1 is a drawing for explaining an example of a unit cell included in a bipolar battery according to an embodiment of the present disclosure.

[0029] FIG. 2 is a drawing for explaining another example of a unit cell included in a bipolar battery according to an embodiment of the present disclosure.

[0030] FIG. 3 is a perspective view illustrating a frame included in a bipolar battery according to an embodiment of the present disclosure.

[0031] Figure 4 is a cross-sectional view of the frame of Figure 3 viewed from direction A.

[0032] FIG. 5 is a drawing for explaining the series connection of unit cells included in a bipolar battery according to an embodiment of the present disclosure.

[0033] FIG. 6 is a drawing for explaining a bipolar battery in which unit cells are arranged in series within a frame according to an embodiment of the present disclosure.

[0034] FIG. 7 is a drawing for explaining the parallel connection of unit cells included in a bipolar battery according to an embodiment of the present disclosure.

[0035] FIG. 8 is a plan view from above of a bipolar battery according to an embodiment of the present disclosure.

[0036] FIG. 9 is a drawing for explaining the upper cover of a bipolar battery according to an embodiment of the present disclosure.

[0037] Fig. 10 is a perspective view of the upper cover of Fig. 9 viewed from direction B.

[0038] FIG. 11 is a plan view from above of a bipolar cell with an upper cover coupled thereto, according to one embodiment of the present disclosure.

[0039] FIG. 12 is a perspective view illustrating a bipolar battery according to another embodiment of the present disclosure.

[0040] FIG. 13 is a flowchart illustrating a method for manufacturing a bipolar battery according to an embodiment of the present disclosure.

[0041] The structural or functional descriptions of the embodiments disclosed in this specification or application are merely illustrative for the purpose of explaining embodiments according to the technical idea of ​​the present invention, and the embodiments according to the technical idea of ​​the present invention may be implemented in various forms other than the embodiments disclosed in this specification or application, and the technical idea of ​​the present invention is not construed as being limited to the embodiments described in this specification or application.

[0042] Hereinafter, unless otherwise specifically defined, when a part such as a layer, film, thin film, region, or plate is said to be “on” or “over” another part, this may include not only the case where it is “directly on” the other part, but also the case where there is another part in between.

[0043] FIG. 1 is a drawing for explaining an example of a unit cell included in a bipolar battery according to an embodiment of the present disclosure.

[0044] Referring to FIG. 1, a unit cell (100) of a bipolar battery may include a first electrode (10), a second electrode (20), a bipolar electrode (30), and a solid electrolyte layer (40).

[0045] The first electrode (10) may include a first current collector (11) and a first active material layer (12).

[0046] Any material that has conductivity and can form a first active material layer (12) on one surface can be used as the first current collector (11) without particular limitation. For example, the first current collector (11) may include at least one selected from the group consisting of stainless steel, aluminum, copper, and nickel. In addition, the first current collector (11) may be in the form of carbon being coated on the surface of the above-described stainless steel, aluminum, copper, nickel, etc.

[0047] The thickness of the first current collector (11) can be appropriately selected depending on the intended use of the bipolar battery, etc., but can typically be in the range of 1 µm to 100 µm, and specifically, can be in the range of 5 µm to 50 µm. When the thickness of the first current collector (11) is thin, the occurrence of a short circuit due to breakage can be further prevented. In addition, the shape of the first current collector (11) can be appropriately selected depending on the intended use of the bipolar battery, etc. In one embodiment, the first current collector (11) can be a positive current collector.

[0048] The first active material layer (12) may be formed on one surface of the first current collector (11). In one embodiment, the first active material layer (12) may be a positive electrode active material layer. At this time, the first active material layer (12) may include a positive electrode active material. In the case of a bipolar lithium battery, the positive electrode active material may be lithium oxide, for example, LiNi x Co y Mn z O2, LiNi x Co y Al z O2(0 <x<1, 0<y<1, 0<z<1, x+y+z =1) 등일 수 있다. 일 실시 예에서, 리튬 산화물은 LiCoO2, LiMnO2, Li2NiMn3O8, LiVO2, LiCrO2, LiFePO4, LiCoPO4, LiNiO2, LiNi 1 / 3 Co 1 / 3 Mn 1 / 3 It may be O2, but is not limited thereto. In addition, the positive electrode active material may be in the form of a single crystal or a polycrystalline form.

[0049] In addition, the first active material layer (12) may further include, if necessary, one or more selected from the group consisting of a conductive material, a solid electrolyte, and a binder. The conductive material is a material for improving conductivity, and may be, for example, acetylene black, Ketjen black, carbon fiber, graphene, carbon nanotubes, etc. The solid electrolyte is for improving ionic conductivity of the positive electrode active material layer, and may use the same material as the material described in the description of the solid electrolyte layer (40) described below. In addition, the binder may mediate bonding between the positive electrode current collector and the positive electrode active material layer, thereby improving mechanical stability, and may be, for example, a fluorine-containing binder such as polytetrafluoroethylene (PTFE) or polyvinylidene fluoride (PVDF), or a rubber-based binder such as nitrile butadiene rubber (NBR) or styrene-butadiene rubber (SBR).

[0050] The method for forming the first active material layer (12) is not particularly limited as long as it is a method that can form the first active material layer (12) having a desired thickness in a desired area on the surface of the first current collector (11). For example, a method may be used in which the material of the first active material layer (12) is formed by pressurizing and pressing, or a method may be used in which a slurry containing the material of the first active material layer (12) and a solvent is prepared and the slurry is applied to the surface of the first current collector (11). Alternatively, in another embodiment, a method may be considered in which the first active material layer (12) is first formed on a solid electrolyte layer (40) located below the first active material layer (12) in the unit cell (100), and then the first current collector (11) is disposed on the first active material layer (12).

[0051] The second electrode (20) may include a second current collector (21) and a second active material layer (22).

[0052] Any material that has conductivity and can form a second active material layer (22) on one surface can be used as the second current collector (21) without particular limitation. For example, the second current collector (21) may include at least one selected from the group consisting of stainless steel, aluminum, copper, and nickel. In addition, the second current collector (21) may be in the form of carbon being coated on the surface of the above-described stainless steel, aluminum, copper, nickel, etc.

[0053] The thickness of the second current collector (21) can be appropriately selected depending on the purpose of the bipolar battery, etc., but can typically be in the range of 1 ㎛ to 100 ㎛, and specifically, can be in the range of 5 ㎛ to 50 ㎛. When the thickness of the second current collector (21) is thin, the occurrence of a short circuit due to breakage can be further prevented. In addition, the shape of the second current collector (21) can be appropriately selected depending on the purpose of the bipolar battery, etc. In one embodiment, the second current collector (21) can be a negative current collector.

[0054] The second active material layer (22) may be formed on one surface of the second current collector (21). In one embodiment, the second active material layer (22) may be a negative electrode active material layer. At this time, the second active material layer (22) may include a negative electrode active material. The negative electrode active material may be, for example, a metal active material and a carbon active material, but is not limited thereto. The metal of the negative electrode active material may be, for example, In, Al, Si, and Sn, and the carbon active material may be, for example, mesocarbon microbeads (MCMB), highly oriented graphite (HOPG), hard carbon, soft carbon, and the like, but is not limited thereto.

[0055] In addition, the second active material layer (22) may further include, as necessary, one or more selected from the group consisting of a conductive material, a solid electrolyte, and a binder, similar to the first active material layer (12). In addition, the second active material layer (22) may be manufactured in the same manner as described for the first active material layer (12).

[0056] In an embodiment, the polarities of the first electrode (10) and the second electrode (20) may be opposite. In one embodiment, if the first electrode (10) is an anode as in the example described above, the second electrode (20) may be a cathode. In another embodiment, if the first electrode (10) is a cathode, the second electrode (20) may be an anode.

[0057] The bipolar electrode (30) may include a bipolar current collector (31), a first active material layer (12), and a second active material layer (22).

[0058] Any material that has conductivity and can form a first active material layer (12) on one side and a second active material layer (22) on the other side can be used as the bipolar current collector (31) without particular limitation. For example, the bipolar current collector (31) may include at least one selected from the group consisting of stainless steel, aluminum, copper, and nickel. In addition, in another embodiment, the bipolar current collector (31) may be in the form of two or more selected from the group consisting of stainless steel, aluminum, copper, and nickel bonded together. All of the descriptions regarding the first current collector (11) and the second current collector (21) can be applied to the bipolar current collector (31), and thus, descriptions thereof will not be repeated.

[0059] A first active material layer (12) can be formed on one side of the bipolar collector (31), and a second active material layer (22) can be formed on the other side. This has been described in the description of the first electrode (10) and the second electrode (20), and will not be described again.

[0060] In one embodiment, the first active material layer (12) of the first electrode (10) and the first active material layer (12) of the bipolar electrode (30) may include the same material. In another embodiment, the first active material layer (12) of the first electrode (10) and the first active material layer (12) of the bipolar electrode (30) may include different materials.

[0061] In one embodiment, the second active material layer (22) of the second electrode (20) and the second active material layer (22) of the bipolar electrode (30) may include the same material. In another embodiment, the second active material layer (22) of the second electrode (20) and the second active material layer (22) of the bipolar electrode (30) may include different materials.

[0062] The solid electrolyte layer (40) may include a solid electrolyte. The solid electrolyte layer (40) may be positioned between the first electrode (10) and the bipolar electrode (30), and between the second electrode (20) and the bipolar electrode (30). In one embodiment, when there are multiple bipolar electrodes (30), the solid electrolyte layer (40) may be positioned between each of the bipolar electrodes (30). More specifically, the solid electrolyte layer (40) may be positioned between the first active material layer (12) and the second active material layer (22).

[0063] In an embodiment, the length of the unit cell (100) of the solid electrolyte layer (40) in a direction perpendicular to the stacking direction may be longer than that of the first electrode (10), the second electrode (20), and the bipolar electrode (30). Accordingly, as described below, when arranging the unit cells (100) within the frame, short circuits between the unit cells (100) can be prevented.

[0064] The solid electrolyte layer (40) may include a constituent solid electrolyte. The solid electrolyte is not particularly limited as long as it has ion conductivity, but for example, in the case where the bipolar battery is a bipolar lithium battery, oxide amorphous solid electrolyte materials such as Li2O-B2O3-P2O5, Li2O-SiO2, Li2O-B2O3, Li2O-B2O3-ZnO, sulfide amorphous solid electrolyte materials such as Li2S-SiS2, LiI-Li2S-SiS2, LiI-Li2S-P2S5, LiI-Li2S-B2S3, Li3PO4-Li2S-Si2S, Li3PO4-Li2S-SiS2, Li3PO4-Li2S-SiS, LiI-Li2S-P2O5, LiI-Li3PO4-P2S5, Li2S-P2S5, LPSCI series and LGPS series sulfide crystal structure solid electrolyte materials such as Li3PS5Cl, LiI, LiI-Al2O3, Li3N, Li3N-LiI-LiOH, Li 1＋x Al x Ti 2-x (PO4)3(0≤x≤2), Li 1＋x＋y Ax Ti 2-x Si y P 3-y O 12 (A = Al or Ga, 0≤x≤0.4, 0 <y≤0.6), [(A 1 / 2 Li 1 / 2 ) 1-x B x ]TiO3(A = La, Pr, Nd, Sm, B = Sr or Ba, 0≤x≤0.5), Li5La3Ta2O 12 , Li7La3Zr2O 12 , Li6BaLa2Ta2O 12 , Li3PO (4-3 / 2x) N x (x<1), Li 3.6 Si 0.6 P 0.4 Crystalline oxides and oxynitrides such as O4, Li3YCl6, Li6PS5C l0.5 Br 0.5 Halide solid electrolyte materials such as these can be used as solid electrolytes.

[0065] In another embodiment, the solid electrolyte may be a polymer electrolyte, and specifically, a polymer gel electrolyte. The polymer gel electrolyte may be manufactured by swelling an electrolyte after manufacturing a polymer matrix (physical gel), or by curing a composition in which an electrolyte and a monomer are mixed (chemical gel), depending on the manufacturing method. The polymer gel electrolyte includes an organic electrolyte containing a lithium salt and a polymer resin, and the organic electrolyte may be included in an amount of 60 to 1,000 parts by weight relative to 100 parts by weight of the polymer resin. The polymer applied to the polymer gel electrolyte is not limited to a specific component, but may include, for example, polyether-based, PVC-based, PMMA-based, polyacrylonitrile (PAN), polyvinylidene fluoride (PVdF), poly(vinylidene fluoride-hexafluoropropylene): PVdF-HFP), polyacrylate, polyethylene oxide, or mixtures thereof.

[0066] The lithium salt contained in the polymer gel electrolyte is an ionizable lithium salt, Li + X - can be expressed as . The anion of such lithium salt is, for example, F - , Cl - , Br - , I - , NO3 - , N(CN)2 - , BF4 - , ClO4 - , PF6 - , (CF3)2PF4 - , (CF3)3PF 3- , (CF3)4PF 2- , (CF3)5PF - , (CF3)6P - , CF3SO 3- , CF3CF2SO 3- , (CF3SO2)2N- , (FSO2)2N - , CF3CF2(CF3)2CO - , (CF3SO2)2CH - , (SF5)3C - , (CF3SO2)3C - , CF3(CF2)7SO 3- , CF3CO 2- , CH3CO 2- , SCN - , (CF3CF2SO2)2N - This may include, but is not limited to, the following:

[0067] The solid electrolyte layer (40) may further include a binder in addition to the solid electrolyte. Here, the binder may have the same content as the binder that may be included in the first active material layer (12) described above.

[0068] In one embodiment, the thickness of the solid electrolyte layer (40) may be in the range of 0.1 μm to 1000 μm, specifically in the range of 0.1 μm to 300 μm, and more specifically in the range of 0.1 μm to 200 μm.

[0069] The method for forming the solid electrolyte layer (40) is not particularly limited, and examples thereof include a method for forming the solid electrolyte layer (40) by pressurizing the material, a method for forming the solid electrolyte layer (40) by preparing a slurry containing the material of the solid electrolyte layer (40) and a solvent, and applying the slurry on a current collector having an electrode active material layer formed thereon, or a method for forming the solid electrolyte layer (40) by coating the slurry on a current collector, drying the slurry, and then manufacturing the slurry into a free-standing film. In one embodiment, by using a method for applying a slurry, it may be easier to form the solid electrolyte layer (40) by covering the electrode active material layer. Here, the electrode active material layer may be a first active material layer (12) or a second active material layer (22), and the current collector may be a first current collector (11), a second current collector (21), or a bipolar current collector (31).

[0070] As illustrated in FIG. 1, a bipolar electrode (30) and a solid electrolyte layer (40) may be interposed between the first electrode (10) and the second electrode (20) in the unit cell (100). In one embodiment, one or more bipolar electrodes (30) may be positioned between the first electrode (10) and the second electrode (20), and a plurality of solid electrolyte layers (40) may be positioned.

[0071] In an embodiment, the unit cell (100) may be in the form of a stack of a first electrode (10), a second electrode (20), one or more bipolar electrodes (30), and a plurality of solid electrolyte layers (40). The first electrode (10) and the second electrode (20) may be positioned at each of the two ends of the unit cell (100) in the stacking direction. More specifically, a first current collector (11) and a second current collector (21) may be positioned at each of the two ends of the unit cell (100) in the stacking direction.

[0072] FIG. 2 is a drawing for explaining another example of a unit cell included in a bipolar battery according to an embodiment of the present disclosure.

[0073] Referring to FIG. 2, a unit cell (100) of a bipolar battery may include a plurality of bipolar electrodes (30). Solid electrolyte layers (40) may be positioned between the plurality of bipolar electrodes (30).

[0074] In one embodiment, the first active material layers (12) of each of the plurality of bipolar electrodes (30) may include the same material. In another embodiment, the first active material layers (12) of at least some of the plurality of bipolar electrodes (30) may include different materials.

[0075] In one embodiment, the second active material layers (22) of each of the plurality of bipolar electrodes (30) may include the same material. In another embodiment, the second active material layers (22) of at least some of the plurality of bipolar electrodes (30) may include different materials.

[0076] By repeatedly arranging bipolar electrodes (30) in the form of a first active material layer (12), a bipolar current collector (31), and a second active material layer (22) being laminated, a unit cell (100) can be in the form of a plurality of bipolar battery cells connected in series.

[0077] By including a plurality of bipolar electrodes (30) as shown in Fig. 2, the output voltage of the entire bipolar battery can be increased.

[0078] FIG. 3 is a perspective view illustrating a frame included in a bipolar battery according to an embodiment of the present disclosure.

[0079] Figure 4 is a cross-sectional view of the frame of Figure 3 viewed from direction A.

[0080] Referring to FIGS. 1, 3, and 4, the frame (200) may extend in the x-axis direction and the y-axis direction and may define a plurality of regions (230). In an embodiment, the frame (200) may include a lower plate (220) at one end in the z-axis direction, and may include a first partition wall portion (210) extending in the x-axis direction and the y-axis direction on the lower plate (220).

[0081] In an embodiment, unit cells (100) in which a first electrode (10), a second electrode (20), and a solid electrolyte are stacked in the z-axis direction may be arranged on a lower plate (220), and more specifically, the unit cells (100) may be arranged in a plurality of regions (230) partitioned by first partition walls (210) extending in the x-axis direction and the y-axis direction. In the present specification, the x-axis direction may be defined as a first direction, the y-axis direction as a second direction, and the z-axis direction as a third direction. Accordingly, the first direction, the second direction, and the third direction may be orthogonal to each other.

[0082] In an embodiment, the frame (200) may include an insulating material. Accordingly, the frame (200) may electrically isolate the unit cells (100). In an embodiment, the frame (200) may insulate adjacent unit cells (100) in the x-axis direction and the y-axis direction from each other.

[0083] The frame (200) may include an elastic material. In one embodiment, when the bipolar battery is operated, pressure may be applied from the outside, and the frame (200) including the elastic material may be appropriately compressed by the pressure from the outside, and may normally separate a plurality of unit cells (100) without being damaged despite the external pressure.

[0084] The frame (200) may include, but is not limited to, one or more materials selected from the group consisting of, for example, polyurethane, natural rubber, spandex, isobutylene isoprene rubber (IIR), fluoroelastomer, elastomer, ethylene-propylene rubber (EPR), styrene-butadiene rubber (SBR), chloroprene, elastomer, rubber epichlorohydrin, nylon, terpene, isoprene rubber, polybutadiene, nitrile rubber, thermoplastic elastomer, silicone rubber, ethylene-propylene-diene rubber (EPDM), ethylene vinyl acetate (EVA), halogenated butyl rubber, neoprene, and copolymers thereof. Alternatively, in another embodiment, the frame (200) may be a nonwoven fabric or a porous material, for example, a nonwoven fabric or sheet comprising one or more materials selected from the group consisting of olefin-based porous materials, glass fibers, and polyethylene.

[0085] FIG. 5 is a drawing for explaining the series connection of unit cells included in a bipolar battery according to an embodiment of the present disclosure.

[0086] Referring to FIG. 5, in an embodiment, unit cells (100) adjacent in the x-axis direction may be arranged so that first electrodes (10) and second electrodes (20) are alternately positioned at both ends in the z-axis direction. Unit cells (100) adjacent in the x-axis direction may be connected to each other in series. Accordingly, the first electrodes (10) and second electrodes (20) of the unit cells (100) adjacent in the x-axis direction may be electrically connected to each other. The first electrodes (10) and second electrodes (20) of the unit cells (100) adjacent in the x-axis direction may be electrically connected to each other through a conductor (300).

[0087] In one embodiment, the first electrode (10) and the second electrode (20) at the upper portions of the neighboring unit cells (100) in the x-axis direction may be electrically connected to each other, or the first electrode (10) and the second electrode (20) at the lower portions may be electrically connected to each other. Here, the upper portion and the lower portion of the unit cell (100) may be opposite ends of the unit cell (100) in the z-axis direction.

[0088] FIG. 6 is a drawing for explaining a bipolar battery in which unit cells are arranged in series within a frame according to an embodiment of the present disclosure.

[0089] Referring to FIG. 6, unit cells (100) may be arranged in a plurality of regions partitioned by a frame (200). In an embodiment, unit cells (100) adjacent in the x-axis direction may be arranged such that first electrodes (10) and second electrodes (20) are alternately positioned at both ends in the z-axis direction.

[0090] In one embodiment, the first electrode (10) and the second electrode (20) at the lower ends of the neighboring unit cells (100) in the x-axis direction may be electrically connected to each other by a first conducting wire (300a). In one embodiment, the first conducting wire (300a) may be pre-arranged on the frame (200) before arranging the unit cells (100). In one embodiment, the first conducting wire (300a) may be arranged to pass through a plurality of regions partitioned by the frame (200). Thereafter, the unit cells (100) may be arranged so that the lower ends of the unit cells (100) contact the first conducting wire (300a). In one embodiment, an insulation treatment may be performed on the first conducting wire (300a) before the unit cells (100) are arranged. For example, by placing insulating tape on at least some of the portions of the first conductor (300a) that do not come into contact with the unit cells (100), an unintentional short circuit can be prevented from occurring.

[0091] In one embodiment, the first electrode (10) and the second electrode (20) at the upper ends of the unit cells (100) adjacent to each other in the x-axis direction may be electrically connected to each other by a second conductor (300b). In the embodiment, the second conductor (300b) may be formed to contact the upper ends of the unit cells (100) after the unit cells (100) are arranged.

[0092] In one embodiment, the height of the frame (200) in the z-axis direction may be less than or equal to the height of the unit cells (100) in the z-axis direction. More specifically, the height of the frame (200) in the z-axis direction may be equal to the height of the unit cells (100) in the z-axis direction. Accordingly, the unit cells (100) may be more stably arranged in the areas partitioned by the frame (200).

[0093] FIG. 7 is a drawing for explaining the parallel connection of unit cells included in a bipolar battery according to an embodiment of the present disclosure.

[0094] Referring to FIGS. 6 and 7, within a bipolar battery (1000), the first electrodes (10) of the unit cells located at one end in the x-axis direction may be electrically connected to each other along the second direction. In an embodiment, the first electrodes (10) of the unit cells located at one end in the x-axis direction may be electrically connected to each other through the first electrode tab (400a).

[0095] The second electrodes (20) of the unit cells located at the other end in the x-axis direction can be electrically connected to each other along the second direction. In an embodiment, the second electrodes (20) of the unit cells located at the other end in the x-axis direction can be electrically connected to each other through the second electrode tab (400b).

[0096] In one embodiment, as shown in FIGS. 6 and 7, the first electrodes (10) of the unit cells located at one end in the x-axis direction and the second electrodes (20) of the unit cells located at the other end in the x-axis direction may be connected to the first electrode tab (400a) and the second electrode tab (400b) via the second conductor (300b), respectively.

[0097] In another embodiment, at least one of the first electrodes (10) of the unit cells located at one end in the x-axis direction and the second electrodes (20) of the unit cells located at the other end in the x-axis direction may be connected to the first electrode tab (400a) and the second electrode tab (400b) via the first conductor (300a).

[0098] Accordingly, a group of unit cells composed of unit cells (100) arranged along the x-axis direction can be connected in parallel to each other along the y-axis direction.

[0099] FIG. 8 is a plan view from above of a bipolar battery according to an embodiment of the present disclosure.

[0100] Referring to FIGS. 7 and 8, within a bipolar battery (1000), two unit cells (100) may be arranged adjacent to each other in the x-axis direction, and two unit cells (100) may be arranged adjacent to each other in the y-axis direction. However, the present invention is not limited thereto, and a greater number of unit cells (100) than those illustrated in FIG. 8 may be arranged in the x-axis direction and the y-axis direction, as in FIG. 7.

[0101] Unit cells (100) adjacent in the x-axis direction can be electrically connected to each other through the first conducting wire (300a). However, when the number of unit cells (100) arranged in the x-axis direction increases, unit cells (100) adjacent in the x-axis direction can be connected in series using both the first conducting wire (300a) and the second conducting wire (300b).

[0102] The first electrodes (10) of the unit cells (100) located at one end in the x-axis direction can be electrically connected to each other along the y-axis direction via the first electrode tab (400a). The second electrodes (20) of the unit cells located at the other end in the x-axis direction can be electrically connected to each other along the y-axis direction via the second electrode tab (400b).

[0103] FIG. 9 is a drawing for explaining the upper cover of a bipolar battery according to an embodiment of the present disclosure.

[0104] Fig. 10 is a perspective view of the upper cover of Fig. 9 viewed from direction B.

[0105] Referring to FIGS. 9 and 10, an upper cover (500) may be coupled to a frame (200) in which unit cells (100) are arranged. The upper cover (500) may be arranged at one end, i.e., the upper end, of the unit cells (100) and the frame (200) in the z-axis direction.

[0106] When looking at the upper cover (500) in the B direction, the interior of the upper cover (500) may include an upper plate (520) and a second bulkhead portion (510). The upper plate (520) may be placed at one end of the unit cells (100) in the z-axis direction. In one embodiment, the upper plate (520) may be in contact with the upper ends of the unit cells (100), but is not limited thereto, and an empty space may exist between the upper plate (520) and the upper ends of the unit cells (100).

[0107] The second bulkhead portion (510) may extend in the z-axis direction from the upper plate (520), and more specifically, may extend downward from the upper plate (520). The second bulkhead portion (510) may be connected to the first bulkhead portion (210) included in the frame.

[0108] The upper cover (500) may include an insulating material. Accordingly, the upper cover (500) may electrically isolate the unit cells (100). In an embodiment, the upper cover (500) may insulate adjacent unit cells (100) in the x-axis direction and the y-axis direction from each other. For example, when the height of the unit cells (100) in the z-axis direction is higher than the height of the frame (200) in the z-axis direction, the portion of the unit cells (100) that exceeds the height of the frame (200) may be insulated by the upper cover (500).

[0109] The upper cover (500) may include an elastic material. In one embodiment, when the bipolar battery is operated, pressure may be applied from the outside, and the upper cover (500) including the elastic material may be appropriately compressed by the pressure from the outside, and may normally separate a plurality of unit cells (100) without being damaged despite the external pressure.

[0110] The upper cover (500) may include, but is not limited to, one or more materials selected from the group consisting of, for example, polyurethane, natural rubber, spandex, isobutylene isoprene rubber (IIR), fluoroelastomer, elastomer, ethylene-propylene rubber (EPR), styrene-butadiene rubber (SBR), chloroprene, elastomer, rubber epichlorohydrin, nylon, terpene, isoprene rubber, polybutadiene, nitrile rubber, thermoplastic elastomer, silicone rubber, ethylene-propylene-diene rubber (EPDM), ethylene vinyl acetate (EVA), halogenated butyl rubber, neoprene, and copolymers thereof. Alternatively, in another embodiment, the upper cover (500) may be a nonwoven fabric or a porous material, for example, a nonwoven fabric or sheet comprising one or more materials selected from the group consisting of olefin-based porous materials, glass fibers, and polyethylene.

[0111] FIG. 11 is a plan view from above of a bipolar cell with an upper cover coupled thereto, according to one embodiment of the present disclosure.

[0112] Referring to FIGS. 6 to 11, a bipolar battery (1000) may include a plurality of unit cells (100), and the unit cells (100) may be arranged within a space formed by the frame (200) and the upper cover (500) being joined to each other.

[0113] In an embodiment, the first electrodes (10) of the unit cells (100) located at one end in the x-axis direction may be electrically connected to each other along the y-axis direction via the first electrode tab (400a), and the second electrodes (20) of the unit cells (100) located at the other end in the x-axis direction may be electrically connected to each other along the second direction via the second electrode tab (400b).

[0114] FIG. 12 is a perspective view illustrating a bipolar battery according to another embodiment of the present disclosure.

[0115] Referring to FIG. 12, the frame (200) and the upper cover (500) of the bipolar battery (1000) can be combined in a clamshell form. That is, although FIG. 9 illustrates that the frame (200) and the upper cover (500), which are separate from each other, are combined with each other, the bipolar battery (1000) in FIG. 12 may include a fixing portion in which at least a portion of the frame (200) and the upper cover (500) are fixed to each other, and the frame (200) and the upper cover (500) can be opened and closed with the fixing portion as an axis.

[0116] The unit cells (100) can be placed while the frame (200) and the upper cover (500) are open, and after the unit cells (100) are placed, the frame (200) and the upper cover (500) are closed, thereby sealing the unit cells (100).

[0117] When using a frame (200) and an upper cover (500) formed in a clamshell shape as shown in Fig. 12, the sealing process can be reduced, thereby improving process efficiency and improving the energy efficiency of the bipolar battery (1000).

[0118] FIG. 13 is a flowchart illustrating a method for manufacturing a bipolar battery according to an embodiment of the present disclosure.

[0119] Referring to FIGS. 6, 7, and 13, unit cells (100) can be arranged in each of a plurality of regions partitioned by a frame (200) in operation S100. The frame (200) can partition a plurality of regions as it extends in the x-axis direction and the y-axis direction, and unit cells including a first electrode, a solid electrolyte, and a second electrode stacked in the z-axis direction can be arranged in the plurality of regions.

[0120] In one embodiment, a first conductor (300a) may be first placed on a frame (200) before the unit cells (100) are placed, and the unit cells (100) may be placed in a plurality of regions such that the lower ends of the unit cells (100) are in contact with the first conductor (300a). Before the unit cells (100) are placed, a portion of the first conductor (300a) that is not in contact with the unit cells (100) may be insulated. For example, an insulating tape may be attached around a portion of the first conductor (300a) that is not in contact with the unit cells (100).

[0121] In the S200 operation, adjacent unit cells (100) in the x-axis direction can be connected in series. Specifically, the first electrode and the second electrode located at the upper portions of the adjacent unit cells (100) in the x-axis direction can be electrically connected to each other, or the first electrode and the second electrode located at the lower portions of the adjacent unit cells (100) in the x-axis direction can be electrically connected to each other.

[0122] In an embodiment, the first electrode and the second electrode located at the upper portions of the adjacent unit cells (100) in the x-axis direction can be electrically connected to each other through an operation of arranging the second conductor (300b) at the upper portions of the unit cells (100). In an embodiment, the first electrode and the second electrode located at the lower portions of the adjacent unit cells (100) in the x-axis direction can be electrically connected to each other through the first conductor (300a) pre-arranged on the frame (200).

[0123] In operation S300, the first electrodes of the unit cells (100) located at one end in the x-axis direction can be electrically connected to each other along the y-axis direction, and the second electrodes of the unit cells (100) located at the other end in the x-axis direction can be electrically connected to each other along the y-axis direction. The first electrodes of the unit cells (100) located at one end in the x-axis direction can be connected to each other through the first electrode tab (400a), and the first electrodes of the unit cells (100) located at the other end in the x-axis direction can be connected to each other through the second electrode tab (400b). Through operation S300, the unit cell groups including the unit cells (100) arranged along the x-axis direction can be connected in parallel to each other.

[0124] In addition, an operation of combining an upper cover (500) with the upper portion of the unit cells (100) and the frame (200) can be further performed. The upper cover (500) can seal the unit cells (100) arranged inside by combining with the frame (200).

[0125] The present disclosure can provide an electrode that prevents wrinkles and swelling and exhibits excellent capacity retention and energy density. Furthermore, the present disclosure can provide a battery cell, a battery module, and a battery pack comprising the electrode, and an electrical device comprising at least one of the battery cell, battery module, and battery pack.

Claims

1. A frame extending in the first direction and the second direction and dividing a plurality of regions; and Unit cells each including a first electrode, a solid electrolyte, and a second electrode, each of which is arranged in each of the above-mentioned multiple regions and each of which is stacked in a third direction; The unit cells adjacent to each other in the first direction are respectively The first electrodes and the second electrodes are arranged alternately at both ends in the third direction, The unit cells adjacent to each other in the first direction are electrically connected in series with each other, The first electrodes of the unit cells located at one end in the first direction are electrically connected to each other along the second direction, The second electrodes of the unit cells located at the other end in the first direction are electrically connected to each other along the second direction, A bipolar cell in which the first, second and third directions are orthogonal to each other.

2. In paragraph 1, A first electrode tab electrically connecting the first electrodes of the unit cells located at one end in the first direction; and A bipolar battery further comprising a second electrode tab electrically connecting second electrodes of unit cells located at the other end in the first direction to each other.

3. In the first paragraph, the length of the solid electrolyte in the first direction is A bipolar cell longer than the first and second electrodes.

4. In the first paragraph, the height of the frame in the third direction is, A bipolar cell having a height equal to or less than the third direction of the above unit cells.

5. In the first paragraph, the unit cells adjacent to each other in the first direction are The first electrode and the second electrode at the upper part are electrically connected to each other, or A bipolar cell in which the first and second electrodes at the lower end are electrically connected to each other.

6. In paragraph 1, A bipolar battery further comprising: an upper cover disposed at one end of the unit cells and the frame in the third direction, the upper cover including an insulating material; 7. In paragraph 6, the frame, A lower plate on which the unit cells are arranged on one side in the third direction; and A bipolar battery comprising a first barrier rib extending in a third direction from the lower plate, dividing the plurality of regions, and insulating the unit cells from each other in the first direction and the second direction.

8. In paragraph 7, the upper cover, an upper plate arranged at one end of the third direction of the above unit cells; and A bipolar battery comprising a second baffle portion extending in a third direction from the upper plate and connected to the first baffle portion.

9. In the first paragraph, within the unit cell, A bipolar battery wherein the first electrode and the second electrode are respectively positioned at opposite ends in the third direction, and the solid electrolyte is positioned between the first electrode and the second electrode.

10. In the 9th paragraph, the unit cell is between the first electrode and the second electrode, A bipolar battery comprising at least one bipolar electrode, the bipolar current collector comprising a first active material layer formed on one surface of the bipolar current collector and a second active material layer formed on the other surface of the bipolar current collector.

11. In the first paragraph, the frame, A bipolar battery containing insulating material.

12. In the 11th paragraph, the frame, A bipolar battery comprising an elastic material.

13. In the 12th paragraph, the frame, A bipolar battery comprising at least one material selected from the group consisting of polyurethane, natural rubber, spandex, isobutylene isoprene rubber (IIR), fluoroelastomer, elastomer, ethylene-propylene rubber (EPR), styrene-butadiene rubber (SBR), chloroprene, elastin, rubber epichlorohydrin, nylon, terpene, isoprene rubber, polybutadiene, nitrile rubber, thermoplastic elastomer, silicone rubber, ethylene-propylene-diene rubber (EPDM), ethylene vinyl acetate (EVA), halogenated butyl rubber, neoprene, and copolymers thereof.

14. In paragraph 6, A bipolar battery further comprising a fixing member in which the frame and the upper cover are joined and fixed.

15. In the 14th paragraph, the frame and the upper cover, A bipolar battery that opens and closes with the above fixed part as an axis.

16. A step of arranging unit cells in each of a plurality of regions defined by frames extending in the first direction and the second direction; a step of connecting adjacent unit cells in series in the first direction; and A step of electrically connecting first electrodes of unit cells located at one end in the first direction to each other along the second direction, and electrically connecting second electrodes of unit cells located at the other end in the first direction to each other along the second direction; The above unit cells are, It comprises a first electrode, a solid electrolyte and a second electrode laminated in a third direction, The unit cells adjacent to each other in the first direction are respectively The first electrodes and the second electrodes are arranged alternately at both ends in the third direction, A method for manufacturing a bipolar battery, wherein the first direction, the second direction, and the third direction are orthogonal to each other.

17. In the 16th paragraph, the step of connecting the adjacent unit cells in series in the first direction is as follows: A step of electrically connecting the first electrode and the second electrode located at the upper portions of the adjacent unit cells in the first direction; or A method for manufacturing a bipolar battery, comprising: a step of electrically connecting first electrodes and second electrodes located at lower ends of adjacent unit cells in the first direction to each other.

18. In paragraph 16, A method for manufacturing a bipolar battery further comprising the step of bonding an upper cover including an insulating material to one end of the unit cells and the frame in the third direction.

19. In the 16th paragraph, the step of arranging the unit cells is: a step of arranging a wire on the above frame; and A method for manufacturing a bipolar battery, comprising: a step of arranging the unit cells in the plurality of regions such that one end of the unit cells in the third direction is in contact with the conductor; 20. In the 19th paragraph, the step of arranging the unit cells is: A method for manufacturing a bipolar battery, further comprising the step of insulating a portion of the conductor that does not come into contact with the unit cells.

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