Energy storage module and energy storage device

Abstract

To provide a power storage module and a power storage device with which, even when a frame is installed around a liquid poring mouth through which an electrolyte is injected, it is possible to suppress an increase in lamination direction size when assembled as the power storage device.SOLUTION: The power storage module comprises a body unit in which a plurality of communication paths are disposed, and a liquid pouring unit having a plurality of liquid pouring mouths that are attached to one side of the body unit and that communicate with each of the communication paths. In a plurality of liquid pouring frames disposed in the body unit, there exist a first liquid pouring frame that is a section of the liquid pouring frame protruding from the body unit to at least one side in a first direction, and a second liquid pouring frame that is a section of the liquid pouring frame protruding from the body unit to at least the other side in the first direction. The amount of protrusion of the section of the liquid pouring frame protruding from the body unit to the one side is larger for the first liquid pouring frame than for the second liquid pouring frame, and the amount of protrusion of the section of the liquid pouring frame protruding from the body unit to the other side is larger for the second liquid pouring frame than for the first liquid pouring frame.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to an electricity storage module and an electricity storage device. [Background technology]

[0002] There is known an energy storage module having a stack of battery cells, each of which includes an electrode plate, a positive electrode provided on one side of the electrode plate, and a negative electrode provided on the other side of the electrode plate (see, for example, Patent Document 1). In such an energy storage module, the stack is surrounded by a resin sealant (sealing portion). A liquid injection port (a communication passage connecting the inside and outside of the battery cell) is formed on a side of the resin sealing portion along the stacking direction of the stack (the main body of the energy storage module) for injecting an electrolyte into each battery cell of the energy storage module. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2012-234823 Summary of the Invention [Problem to be solved by the invention]

[0004] It is desirable to inject electrolyte into each battery cell while maintaining a seal (maintaining airtightness) between the injection port provided on the side of the main body of the energy storage module and the attachment for injecting the electrolyte. Therefore, to ensure airtightness between the injection port and the attachment attached to the injection port, it is conceivable to form a frame that functions as a sealing surface around each injection port of the energy storage module. In this case, the frame formed to surround the injection port connected to the outermost cell of the energy storage module protrudes from the main body of the energy storage module in the stacking direction when viewed from the side of the energy storage module. Therefore, the stacking direction size around the injection port of the energy storage module is larger than the stacking direction size of the other parts. In an energy storage device configured by stacking multiple energy storage modules with locally varying thicknesses, adjacent modules in the stacking direction are arranged at a predetermined interval to prevent contact with each other, resulting in a large physical size of the energy storage device in the stacking direction.

[0005] Therefore, an object of the present invention is to provide an energy storage module and an energy storage device that can prevent the stacking direction size from increasing when assembled into an energy storage device, even when a frame body is provided around the filling port for injecting the electrolyte. [Means for solving the problem]

[0006] The electricity storage module of the present invention is an electricity storage module used in a stacked electricity storage device, and includes: an electrode stack in which bipolar electrodes, each having a positive electrode formed on a first surface of a current collector and a negative electrode formed on a second surface opposite to the first surface, are stacked along a first direction; and a sealing portion that forms an internal space between adjacent current collectors in the first direction and seals the internal space, the sealing portion being a cylindrical body formed in a rectangular frame shape so as to surround the electrode stack when viewed from the first direction, the sealing portion having a main body portion on one side of the cylindrical body and a plurality of communication passages that communicate with each of the plurality of internal spaces; and a liquid injection portion attached to one side of the main body portion and having a plurality of liquid injection ports that communicate with each of the communication passages, the liquid injection portion being arranged along the first direction. The liquid filling frame has a plurality of liquid filling frames that independently surround the ends of a plurality of communicating paths to form liquid filling ports, and the plurality of liquid filling frames are arranged on one side of the main body in a second direction perpendicular to the first direction, and the plurality of liquid filling frames arranged in the second direction include a first liquid filling frame in which a portion of the liquid filling frame protrudes from the main body on at least one side in the first direction, and a second liquid filling frame in which a portion of the liquid filling frame protrudes from the main body on at least the other side in the first direction, and the amount by which the portion of the liquid filling frame protrudes from the main body on one side in the first direction is greater for the first liquid filling frame than for the second liquid filling frame, and the amount by which the portion of the liquid filling frame protrudes from the main body on the other side in the first direction is greater for the second liquid filling frame than for the first liquid filling frame.

[0007] The energy storage device is formed by stacking a plurality of energy storage modules. In the energy storage module of the present invention, a liquid injection frame forming a liquid injection portion into which an electrolyte solution is injected protrudes from a main body portion in a first direction, which is the stacking direction, but the amount by which a portion of the liquid injection frame protrudes from the main body portion on one side in the first direction is greater for the first liquid injection frame than for the second liquid injection frame, and the amount by which a portion of the liquid injection frame protrudes from the main body portion on the other side in the first direction is greater for the second liquid injection frame than for the first liquid injection frame. This prevents the portions that protrude significantly from the main body portion from facing each other in the first direction, and prevents the size of the energy storage device from increasing in the stacking direction when assembled.

[0008] In the energy storage module of the present invention, a portion of the first liquid filling frame may protrude from the main body portion only on one side in the first direction, and a portion of the second liquid filling frame may protrude from the main body portion only on the other side in the first direction. In this configuration, the first liquid filling frame and the second liquid filling frame each have a configuration in which one side does not protrude from the main body portion in the stacking direction. This prevents the portions that significantly protrude from the main body portion from facing each other in the first direction, and prevents an increase in the size in the stacking direction when assembled into an energy storage device.

[0009] In the energy storage module of the present invention, a plurality of first liquid filling frames and a plurality of second liquid filling frames may be provided, and the first liquid filling frames may be arranged continuously in the second direction, and the second liquid filling frames may be arranged continuously in the second direction. With this configuration, the liquid filling section can be easily manufactured.

[0010] In the energy storage module of the present invention, a plurality of first liquid filling frames and a plurality of second liquid filling frames may be provided, and the first liquid filling frames and the second liquid filling frames may be arranged alternately in the second direction. With this configuration, it is possible to prevent the energy storage modules adjacent to each other in the stacking direction from moving in the second direction perpendicular to the stacking direction.

[0011] In the energy storage module of the present invention, the liquid injection part may further have an overhang part connected to the main body part and covering part of both end faces of the electrode stack in the first direction. With this configuration, the liquid injection part can be provided more stably with respect to the main body part.

[0012] In the electricity storage module of the present invention, a laminate film that covers the liquid filling port may be attached to the liquid filling frame. With this configuration, the liquid filling port and therefore the communication path can be sealed, thereby blocking communication between the internal space and the outside.

[0013] In the energy storage module of the present invention, when the positive electrode constituting one end of the stack in the first direction is a terminating positive electrode and the negative electrode constituting the other end of the stack in the first direction is a terminating negative electrode, one surface of the current collector on which the positive electrode is not formed in the terminating positive electrode and one surface of the current collector on which the negative electrode is not formed in the terminating negative electrode may have an exposed surface exposed to the outside. In this configuration, multiple energy storage modules can be electrically connected in series simply by stacking the energy storage modules with a conductive plate attached to the exposed surface.

[0014] The energy storage device of the present invention may include a plurality of the energy storage modules described above and a conductive plate, and the energy storage modules may be stacked in the first direction via the conductive plate in contact with the exposed surface. In this configuration, the plurality of energy storage modules can be electrically connected in series simply by stacking the energy storage modules with the conductive plate in contact with the exposed surface.

[0015] In the energy storage device of the present invention, when the energy storage modules are stacked so that one side is vertically upper and the other side is vertically lower, and so that the first liquid pouring frame and the second liquid pouring frame are arranged vertically, when adjacent energy storage modules are viewed in the vertical direction, the lower end of the second liquid pouring frame of one energy storage module may be located lower than the upper end of the first liquid pouring frame of the other energy storage module. In this configuration, a step is formed in the stacking direction between the first and second liquid pouring frames. Therefore, when stacking multiple modules, this step can be used to position the modules. [Effects of the Invention]

[0016] According to the present invention, even when a frame is provided around the injection port for injecting the electrolyte, it is possible to prevent the size in the stacking direction from increasing when assembled into an electricity storage device. [Brief explanation of the drawings]

[0017] [Figure 1]FIG. 1 is a side view of an electricity storage module according to one embodiment, as viewed from the X-axis direction. [Figure 2] FIG. 2 is a top view of the energy storage module of one embodiment as viewed from above in the Z-axis direction. [Figure 3] FIG. 3 is a cross-sectional view taken along line III-III shown in FIGS. [Figure 4] FIG. 4 is a side view of the power storage device in which the power storage modules of FIG. 1 are stacked, as viewed from the X-axis direction. [Figure 5] 5 is a schematic cross-sectional view of the electricity storage device of FIG. 4 taken along line VV. [Figure 6] FIG. 6 is a side view of the energy storage module according to the modified example, as viewed from the X-axis direction. DETAILED DESCRIPTION OF THE INVENTION

[0018] An embodiment of the present invention will be described in detail below with reference to the accompanying drawings. In the description of the drawings, the same or equivalent elements are designated by the same reference numerals, and redundant explanations will be omitted. Figures 1 to 6 show an XYZ orthogonal coordinate system, in which the X-axis direction, Y-axis direction (second direction), and Z-axis direction (first direction) are orthogonal to one another.

[0019] 1 to 3 is included in a power storage device 100 (see FIG. 5) used as a battery for various vehicles such as forklifts, hybrid vehicles, and electric vehicles. The power storage module 1 is a secondary battery such as a nickel-metal hydride secondary battery or a lithium-ion secondary battery. In this embodiment, the power storage module 1 is a lithium-ion secondary battery.

[0020] The energy storage device 100 includes an electrode stack 3 in which a plurality of energy storage cells 2 are stacked (laminated). Each energy storage cell 2 includes a positive electrode 11, a negative electrode 12, a separator 13, and a sealing portion 14. The positive electrode 11 and the negative electrode 12 are arranged facing each other. The facing direction of the positive electrode 11 and the negative electrode 12 coincides with the stacking direction (first direction) D (Z-axis direction) of the plurality of energy storage cells 2. The positive electrode 11 and the negative electrode 12 are, for example, rectangular electrodes when viewed from the stacking direction D. The energy storage cell 2 may be a large battery with one side exceeding 1 m.

[0021] The positive electrode 11 includes a current collector 21 and a positive electrode active material layer 23. The current collector 21 has a first surface 21a and a second surface 21b facing opposite to each other, and an edge portion 21c. The positive electrode active material layer 23 is provided on the first surface 21a. The positive electrode active material layer 23 is not provided on the second surface 21b. The positive electrode active material layer 23 is not provided on the edge portion 21c, on either the first surface 21a side or the second surface 21b side. In other words, the first surface 21a has an area on the edge portion 21c where the positive electrode active material layer 23 is not provided. When viewed from the stacking direction D, the edge portion 21c is located outside the area of ​​the current collector 21 where the positive electrode active material layer 23 is provided. The positive electrode 11 may be a large electrode with a side measuring more than 1 m.

[0022] The negative electrode 12 includes a current collector 22 and a negative electrode active material layer 24. The current collector 22 has a first surface 22a and a second surface 22b facing opposite to each other, and an edge portion 22c. The negative electrode active material layer 24 is provided on the first surface 22a. The negative electrode active material layer 24 faces the positive electrode active material layer 23 in the stacking direction D. The negative electrode active material layer 24 is not provided on the second surface 22b. The negative electrode active material layer 24 is not provided on the edge portion 22c on either the first surface 22a side or the second surface 22b side. In other words, the first surface 22a has a region on the edge portion 22c where the negative electrode active material layer 24 is not provided. The edge portion 22c is located outside the region of the current collector 22 where the negative electrode active material layer 24 is provided, as viewed from the stacking direction D. The negative electrode 12 may be a large electrode with a side length of more than 1 m.

[0023] The positive electrode 11 and the negative electrode 12 are arranged such that the positive electrode active material layer 23 and the negative electrode active material layer 24 face each other in the stacking direction D. In this embodiment, the positive electrode active material layer 23 and the negative electrode active material layer 24 are both formed in a rectangular shape when viewed from the stacking direction D. The negative electrode active material layer 24 is formed to be slightly larger than the positive electrode active material layer 23. When viewed from the stacking direction D, the entire positive electrode active material layer 23 is located inside the outer edge of the negative electrode active material layer 24.

[0024] The electrode stack 3 is formed by stacking a plurality of energy storage cells 2 such that the second surface 21b of the current collector 21 of one energy storage cell 2 and the second surface 22b of the current collector 22 of another energy storage cell 2 are in contact with each other. This electrically connects the plurality of energy storage cells 2 in series. In the energy storage cells 2, 2 adjacent to each other in the stacking direction D, the current collector 21 of one energy storage cell 2 and the current collector 22 of the other energy storage cell 2 are in contact with each other and are electrically connected to each other. For example, the electrode stack 3 may be formed by stacking 30 energy storage cells 2.

[0025] In the electrode stack 3, adjacent power storage cells 2, 2 in the stacking direction D form a pseudo-bipolar electrode 10 in which the mutually contacting current collectors 21 and 22 form a single current collector. A terminal positive electrode including the current collector 21 is disposed at one end of the electrode stack 3 in the stacking direction D. A terminal negative electrode including the current collector 22 is disposed at the other end of the electrode stack 3 in the stacking direction D. The terminal negative electrode provided at one end of the electrode stack 3 in the stacking direction D may have the current collector 22, and the terminal negative electrode provided at the other end of the electrode stack 3 in the stacking direction D may have the current collector 21.

[0026] The current collectors 21 and 22 are chemically inactive electrical conductors that allow current to flow continuously through the positive electrode active material layer 23 and the negative electrode active material layer 24 during charging or discharging of the lithium-ion secondary battery. Examples of materials that can be used to form the current collectors 21 and 22 include metal materials, conductive resin materials, and conductive inorganic materials. Examples of conductive resin materials include resins containing conductive polymer materials or non-conductive polymer materials to which a conductive filler has been added. The current collectors 21 and 22 may have multiple layers, including one or more layers containing the above-mentioned metal materials or conductive resin materials. A coating layer may be formed on the surface of the current collectors 21 and 22 by a known method such as plating or spray coating. The current collectors 21 and 22 may be formed in the form of, for example, a plate, foil, sheet, film, mesh, or the like. When the current collectors 21 and 22 are made of metal foil, examples of the metal foil include aluminum foil, copper foil, nickel foil, titanium foil, and stainless steel foil. The current collectors 21, 22 may be alloy foils or clad foils of the above metals. When the current collectors 21, 22 are foil-shaped, the thickness of the current collectors 21, 22 may be in the range of 1 μm to 100 μm. The current collectors 21, 22 may be integrated, for example, by copper plating one side of an aluminum foil. The current collectors 21, 22 may also be integrated by bonding. The current collectors 21, 22 may be subjected to a surface coating treatment such as vapor deposition or plating. In this embodiment, the current collector 21 is an aluminum foil, and the current collector 22 is a copper foil.

[0027] The positive electrode active material layer 23 includes a positive electrode active material capable of absorbing and releasing charge carriers such as lithium ions. Examples of the positive electrode active material include composite oxides, metallic lithium, and sulfur. The composite oxides contain, for example, at least one of iron, manganese, titanium, nickel, cobalt, and aluminum, and lithium. Examples of the composite oxides include olivine-type lithium iron phosphate (LiFePO4), LiCoO2, and LiNiMnCoO2.

[0028] The negative electrode active material layer 24 includes a negative electrode active material capable of absorbing and releasing charge carriers such as lithium ions. Examples of the negative electrode active material include graphite, artificial graphite, highly oriented graphite, mesocarbon microbeads, hard carbon, soft carbon, and other carbons, metal compounds, elements or compounds thereof that can be alloyed with lithium, and boron-doped carbon. Examples of elements that can be alloyed with lithium include silicon and tin.

[0029] In addition to the active material, the positive electrode active material layer 23 and the negative electrode active material layer 24 may contain a binder and a conductive additive. The binder serves to connect the active material or conductive additive to each other and maintain the conductive network within the electrode. Examples of binders include fluorine-containing resins such as polyvinylidene fluoride, polytetrafluoroethylene, and fluorine rubber; thermoplastic resins such as polypropylene and polyethylene; imide resins such as polyimide and polyamideimide; alkoxysilyl group-containing resins; acrylic resins such as polyacrylic acid and polymethacrylic acid; styrene-butadiene rubber; carboxymethyl cellulose; alginates such as sodium alginate and ammonium alginate; water-soluble cellulose ester crosslinked bodies; and starch-acrylic acid graft polymers. These binders may be used alone or in combination. The conductive additive is, for example, a conductive material such as acetylene black, carbon black, or graphite, and can enhance electrical conductivity. Examples of viscosity-adjusting solvents include N-methyl-2-pyrrolidone.

[0030] To form the positive electrode active material layer 23 and the negative electrode active material layer 24 on the first surfaces 21a and 22a, conventional methods such as roll coating, die coating, dip coating, doctor blade coating, spray coating, and curtain coating are used. Specifically, an active material, a solvent, and, if necessary, a binder and a conductive additive are mixed to produce a slurry-like active material layer-forming composition, which is then applied to the first surfaces 21a and 22a and dried. Examples of the solvent include N-methyl-2-pyrrolidone, methanol, methyl isobutyl ketone, and water. The dried electrode may be compressed to increase electrode density.

[0031] The separator 13 is disposed between the positive electrode 11 and the negative electrode 12 in the stacking direction D. The separator 13 is interposed between the positive electrode 11 and the negative electrode 12. The separator 13 is a component that separates the adjacent positive electrodes 11 and negative electrodes 12 when the energy storage cells 2 are stacked, thereby preventing an electrical short circuit due to contact between the electrodes while allowing charge carriers such as lithium ions to pass through. The separator 13 is disposed between the positive electrode active material layer 23 and the negative electrode active material layer 24 that face each other.

[0032] The separator 13 is formed in a rectangular shape that is slightly larger than the positive electrode active material layer 23 and the negative electrode active material layer 24 and slightly smaller than the current collectors 21, 22 when viewed from the stacking direction D. An end portion 13c of the separator 13 is disposed outside the positive electrode active material layer 23 and the negative electrode active material layer 24 when viewed from the stacking direction D. When viewed from the stacking direction D, the end portion 13c of the separator 13 does not overlap either the positive electrode active material layer 23 or the negative electrode active material layer 24.

[0033] The separator 13 is formed, for example, in a sheet shape. The separator 13 is, for example, a porous sheet or nonwoven fabric containing a polymer that absorbs and retains an electrolyte. Examples of materials that constitute the separator 13 include polypropylene, polyethylene, polyolefin, and polyester. The separator 13 may have a single-layer structure or a multi-layer structure. In the case of a multi-layer structure, the separator 13 may include, for example, a substrate layer and a pair of adhesive layers, and may be bonded and fixed to the positive electrode active material layer 23 and the negative electrode active material layer 24 by the pair of adhesive layers. The separator 13 may also include a ceramic layer that serves as a heat-resistant layer. The separator 13 may also be reinforced with a vinylidene fluoride resin compound.

[0034] The electrolyte impregnated into the separator 13 may be, for example, a liquid electrolyte (electrolyte solution 5) containing a non-aqueous solvent and an electrolyte salt dissolved in the non-aqueous solvent. When the separator 13 is impregnated with an electrolyte, known lithium salts such as LiClO4, LiAsF6, LiPF6, LiBF4, LiCF3SO3, LiN(FSO2)2, and LiN(CF3SO2)2 can be used as the electrolyte salt. In addition, known solvents such as cyclic carbonates, cyclic esters, chain carbonates, chain esters, and ethers can be used as the non-aqueous solvent. Two or more of these known solvent materials may be used in combination.

[0035] When the positive electrode 11 arranged in the outermost layer of the electrode stack 3, i.e., the positive electrode 11 constituting one end of the electrode stack 3 in the stacking direction D, is defined as a terminal positive electrode, and the negative electrode 12 constituting the other end of the electrode stack 3 in the stacking direction D is defined as a terminal negative electrode, the second surface 21b of the current collector 21 on which the positive electrode active material layer 23 is not formed in the terminal positive electrode, and the second surface 22b of the current collector 22 on which the negative electrode active material layer 24 is not formed in the terminal negative electrode, are formed with exposed surfaces 21e, 22e that are exposed to the outside. The exposed surfaces 21e, 22e are surfaces that come into contact with the conductive plate 7 when the energy storage modules 1 are stacked.

[0036] The sealing portion 14 is a member that seals the internal space S between the current collector 21 and the current collector 22. The sealing portion 14 is frame-shaped when viewed from the stacking direction D, and surrounds the periphery of the positive electrode active material layer 23 and the negative electrode active material layer 24. The sealing portion 14 forms an internal space S between the current collector 21 and the current collector 22, which is separated from the outside and is used to accommodate the electrolyte solution 5. In the energy storage cell 2, the internal space S is separated by the current collector 21, the current collector 22, and the sealing portion 14. The electrolyte solution 5 is accommodated in the internal space S. The sealing portion 14 is formed of an electrolyte-resistant resin material such as acid-modified polyethylene (acid-modified PE), acid-modified polypropylene (acid-modified PP), polyethylene, or polypropylene. The sealing portion 14 has electrical insulation properties.

[0037] The sealing portion 14 has a sealing main body portion (main body portion) 140 and a liquid injection portion 50. The sealing main body portion 140 is formed to include a first resin portion 15, a second resin portion 16, and an end surface weld portion 17. The sealing main body portion 140 has thicknesses in the X-axis direction and the Y-axis direction. The first resin portion 15, the second resin portion 16, and the end surface weld portion 17 are each frame-shaped when viewed from the stacking direction D. In the bipolar electrode 10, the first resin portion 15 is provided on the edge portions of the current collectors 21 and 22 so as to be spaced apart from the positive electrode active material layer 23 and the negative electrode active material layer 24. That is, there is a space between the inner circumferential surface of the first resin portion 15 and the outer circumferential surface of the positive electrode active material layer 23, and there is a space between the inner circumferential surface of the first resin portion 15 and the outer circumferential surface of the negative electrode active material layer 24. The first resin portion 15 is provided at the edge portions of the current collector 21 and the current collector 22 so as to cover the first surface 21a of the current collector 21 and the first surface 22a of the current collector 22.

[0038] In a terminal positive electrode constituting one end of the electrode stack 3 in the stacking direction D, the first resin portion 15 is provided at the edge of the current collector 21 so as to be spaced from the positive electrode active material layer 23. That is, there is a space between the inner peripheral surface of the first resin portion 15 and the outer peripheral surface of the positive electrode active material layer 23. The first resin portion 15 is provided at the edge of the current collector 21 so as to cover the first surface 21a and the second surface 21b. In a terminal negative electrode constituting the other end of the electrode stack 3 in the stacking direction D, the first resin portion 15 is provided at the edge of the current collector 22 so as to be spaced from the negative electrode active material layer 24. That is, there is a space between the inner peripheral surface of the first resin portion 15 and the outer peripheral surface of the negative electrode active material layer 24. The first resin portion 15 is provided at the edge of the current collector 22 so as to cover the first surface 22a and the second surface 22b.

[0039] The second resin portion 16 is disposed between the first resin portions 15 in the Z-axis direction. The second resin portion 16 functions as a joining portion that joins the first resin portions 15, 15 together and also functions as a spacing portion that maintains the spacing between the first resin portions 15, 15. Like the first resin portion 15, the second resin portion 16 is disposed so as to be spaced apart from the positive electrode active material layer 23 and the negative electrode active material layer 24. That is, there is a space between the inner circumferential surface of the second resin portion 16 and the outer circumferential surface of the positive electrode active material layer 23, and there is a space between the inner circumferential surface of the second resin portion 16 and the outer circumferential surface of the negative electrode active material layer 24. The second resin portion 16 is joined to the first resin portion 15 by being welded thereto.

[0040] The end surface weld portion 17 integrates the first resin portion 15 and the second resin portion 16 by welding the outer edge of the first resin portion 15 to the outer edge of the second resin portion 16. The end surface weld portion 17 is formed on at least one of the outer peripheral surfaces of the first resin portion 15 and the second resin portion 16 when viewed from the stacking direction D. The end surface weld portion 17 is formed in a region outside the outer edges of the current collectors 21 and 22 when viewed from the stacking direction D. In this embodiment, the end surface weld portion 17 is formed on all four surfaces that form the outer peripheral surfaces of the first resin portion 15 and the second resin portion 16. The thickness (length in the direction perpendicular to the first direction) of the end surface weld portion 17 on the surface on which the liquid inlet 51 is not formed may be thicker than the thickness of the end surface weld portion 17 on the surface on which the liquid inlet 51 is formed.

[0041] The seal body 140 is formed into a rectangular tubular shape by welding a plurality of first resin portions 15 and second resin portions 16 arranged in the stacking direction D of the electrode stack 3 together, and by welding the outer edge of the first resin portion 15 to the outer edge of the second resin portion 16 by end surface welding portions 17. The seal body 140 of the sealing unit 14 forms side surfaces 140a extending in the stacking direction D from the first resin portion 15 provided on the current collector 21 arranged at one end of the stacking direction D of the electrode stack 3 to the second resin portion 16 provided on the current collector 22 arranged at the other end of the stacking direction D. In other words, the seal body 140 has four side surfaces 140a that are orthogonal to the stacking direction D (the Z-axis direction shown in FIG. 3 ) (the X-axis direction and the Y-axis direction shown in FIG. 3 ). The side surfaces 140a of the seal body 140 are both the side surfaces of the seal 14 and the side surfaces of the energy storage module 1.

[0042] As described above, the sealing main body 140 is a cylindrical body formed in the shape of a rectangular frame so as to surround the electrode stack 3 when viewed from the Z-axis direction. The sealing main body 140 has thicknesses in the X-axis direction and the Y-axis direction. A side portion forming one side surface 140a of the cylindrical sealing main body 140 is provided with a plurality of communication paths 140b that communicate with each of the plurality of internal spaces S. Openings (ends) of the communication paths 140b are formed in one side surface 140a of the sealing main body 140.

[0043] The liquid injection part 50 is provided to inject the electrolyte 5 into the internal space S within the sealing part 14. The liquid injection part 50 is provided on one of the four side surfaces 140a. The liquid injection part 50 is attached to one of the side surfaces 140a of the sealing main body 140, and has a plurality of liquid injection ports 51 that communicate with each of the communication paths 140b. The liquid injection part 50 has a liquid injection main body 52, a liquid injection frame 53, and an overhang part 54. The liquid injection main body 52 is a part that covers the side surface 140a. In this embodiment, the liquid injection main body 52 covers a portion of one of the four side surfaces 140a.

[0044] Liquid injection frame 53 protrudes from liquid injection main body 52 and is provided to connect the connection part of an injection device for electrolyte solution 5 and communication path 140b in a sufficiently sealed state (maintaining airtightness) when injecting electrolyte solution 5 into internal space S of electricity storage module 1. In other words, liquid injection frame 53 has a frame-shaped sealing surface against which the connection part of the injection device is pressed. The frame-shaped sealing surface is formed flat in the X-axis direction and is configured to be able to tightly fit, for example, a rubber packing or the like provided in an injection device for electrolyte solution 5.

[0045] Here, a plurality of communication paths 140b are provided in the Z-axis direction (first direction) of the seal main body 140, and a plurality of communication path groups each provided in the Z-axis direction (first direction) are provided in the Y-axis direction. In this embodiment, three communication paths 140b are arranged in the Z-axis direction, and ten communication path groups each consisting of three communication paths 140b in the Z-axis direction are arranged along the Y-axis direction. The communication paths 140b open to the side surface 140a of the seal main body 140 along the Z-axis direction, and also open to the liquid injection main body 52 surrounded by the liquid injection frame 53, and communicate from the outside of the module to the internal space S.

[0046] The liquid injection frame 53 is formed in the liquid injection main body 52 and surrounds the openings of the plurality of communication paths 140b arranged along the Z-axis direction, independently of one another, to form the liquid injection ports 51. The liquid injection frame 53 of this embodiment is a frame that opens (communicates) the communication paths 140b to the outside and also forms the liquid injection ports 51. More specifically, the liquid injection frame 53 protrudes from the liquid injection main body 52 so as to surround an end of one of the communication paths 140b. The liquid injection port 51 is formed from the inner circumferential surface (inner wall) of the liquid injection frame 53 that protrudes from the liquid injection main body 52 so as to surround an end of one of the communication paths 140b.

[0047] The liquid filling ports 51 are provided corresponding to the communication paths 140b, one for each of the multiple internal spaces S. More specifically, the sealing section 14 of the energy storage module 1 has ten liquid filling frames 53, each with three liquid filling ports 51, arranged in the Y-axis direction. That is, the sealing section 14 of the energy storage module 1 is provided with 30 liquid filling ports 51. The shape of the liquid filling ports 51 as viewed from the extension direction of the liquid filling ports 51 (X-axis direction) is, for example, a rectangle (oblong) that is long in one direction (Y-axis direction). The shape of the liquid filling ports 51 is not limited, and may be, for example, a circle. The liquid filling ports 51 are sealed by a seal section after the electrolyte is poured into them.

[0048] As described above, ten liquid pouring frames 53 are formed in the Y-axis direction on the side surface 140a of the sealing portion 14. The multiple liquid pouring frames 53 include a first liquid pouring frame 50A in which a portion of the liquid pouring frame 53 protrudes from the seal main body 140 only on one side in the stacking direction D (Z-axis direction), and a second liquid pouring frame 50B in which a portion of the liquid pouring frame 53 protrudes from the seal main body 140 only on the other side in the stacking direction D (Z-axis direction). In other words, there are at least two types of liquid pouring frames among the multiple liquid pouring frames 53. Note that "a portion of the liquid pouring frame 53 protrudes from the seal main body 140" means that a portion of the outer shape 53a of the liquid pouring frame 53 protrudes from the seal main body 140 in the stacking direction D (Z-axis direction) when viewed from the X-axis direction.

[0049] As shown in FIG. 3 , in the first liquid injection frame 50A, it is sufficient that the upper part constituting the liquid injection frame 53 protrudes from the seal main body 140 in the stacking direction D, and it is sufficient that the lower part constituting the liquid injection frame 53 protrudes less from the seal main body 140 in the stacking direction D than the upper part constituting the liquid injection frame 53. The lower part constituting the liquid injection frame 53 does not have to protrude from the seal main body 140 in the stacking direction D. In the second liquid injection frame 50B, it is sufficient that the lower part constituting the liquid injection frame 53 protrudes from the seal main body 140 in the stacking direction D, and it is sufficient that the upper part constituting the liquid injection frame 53 protrudes less from the seal main body 140 in the stacking direction D than the lower part constituting the liquid injection frame 53. The upper part constituting the liquid injection frame 53 does not have to protrude from the seal main body 140 in the stacking direction D.

[0050] In this embodiment, some of the multiple liquid pouring frames 53 included in the energy storage module 1 are first liquid pouring frames 50A in which a portion of the liquid pouring frame 53 protrudes from the seal main body 140 only on one side in the stacking direction D, and the remaining multiple liquid pouring frames 53 are second liquid pouring frames 50B in which a portion of the liquid pouring frame 53 protrudes from the seal main body 140 only on the other side in the stacking direction D. In other words, the energy storage module 1 does not include any liquid pouring frames 53 other than the first liquid pouring frames 50A and second liquid pouring frames 50B. Furthermore, the energy storage module 1 of this embodiment is provided with the same number of first liquid pouring frames 50A and second liquid pouring frames 50B. Specifically, five first liquid pouring frames 50A and five second liquid pouring frames 50B are provided.

[0051] As described above, the energy storage module 1 has four side surfaces 140a, and the multiple liquid pouring frames 53 are formed on one of the side surfaces 140a and are arranged along the Y-axis direction, which is perpendicular to the stacking direction D (Z-axis direction). In this embodiment, five first liquid pouring frames 50A are arranged consecutively in the Y-axis direction, and five second liquid pouring frames 50B are arranged consecutively. Note that a connection portion 55 is formed between adjacent liquid pouring frames 53, 53. The connection portion 55 has a surface that is formed flush with the sealing surface of the liquid pouring frame 53 in the X-axis direction.

[0052] A laminate film 59 (see FIG. 3) that covers the liquid filling port 51 is attached to the liquid filling frame 53. The laminate film 59 can be, for example, a known composite laminate film in which a metal foil and a resin layer are bonded together. The metal foil of the composite laminate film can be made of metal such as aluminum, aluminum alloy, stainless steel, or nickel alloy. The resin layer of the composite laminate film can be made of resin such as polyethylene, ethylene vinyl acetate, or polyethylene terephthalate. Note that the laminate film 59 is not shown in FIGS. 1 and 2.

[0053] Such a liquid injection frame 53 can be formed integrally with the sealing portion 14, for example, by injection molding. The liquid injection portion 50 has an overhang portion (build-up portion) 54 that overlaps with the sealing main body 140 when viewed from the stacking direction D. The overhang portion 54 is connected to the sealing main body 140 and covers part of both end faces of the electrode stack 3 in the stacking direction D. The liquid injection frame 53 and the overhang portion 54 may be connected to the sealing main body 140 by welding. The liquid injection frame 53 and the overhang portion 54 may also be formed simultaneously on the sealing main body 140 by injection molding.

[0054] A sheet member 18 having a metal layer is attached to frame-shaped first and second surfaces 14b and 14c of the sealing portion 14, which are surfaces perpendicular to the stacking direction D and formed at both ends of the electrode stack 3. Furthermore, the sheet member 18 is also attached to the outer surface of a liquid injection frame 53 that forms the liquid injection portion 50 formed on the side surface 140a of the sealing portion 14. In this configuration, the metal layer included in the sheet member 18 is made of a material that has a lower hydrogen or moisture permeability coefficient than resin. Therefore, the sheet member 18 has high barrier properties against moisture, and therefore, the intrusion of moisture into the energy storage module through the sealing portion 14 is suppressed compared to when the sealing portion 14 is made of only a resin material.

[0055] Here, the sheet member 18 may be a laminate film. Examples of the laminate film include known composite laminate films in which a metal foil and a resin layer are bonded together. The metal foil of the composite laminate film may be made of a metal such as aluminum, an aluminum alloy, stainless steel, or a nickel alloy. The resin layer of the composite laminate film may be made of a resin such as polyethylene, ethylene vinyl acetate, or polyethylene terephthalate.

[0056] As shown in FIGS. 4 and 5 , the energy storage device 100 is configured by stacking the above-described energy storage modules 1 in the Z-axis direction and electrically connecting the plurality of energy storage modules 1 in series. More specifically, the energy storage device 100 is configured by placing conductive plates 7 in contact with exposed surfaces 22e formed on both ends of the energy storage module 1 and stacking the energy storage modules 1 via the conductive plates 7. In the energy storage device 100, the plurality of liquid injection sections 50 formed on the side surfaces 140a of the plurality of energy storage modules 1 are aligned in the Z-axis direction. In other words, the liquid injection sections 50 of the energy storage modules 1 constituting the energy storage device 100 are aligned in a straight line in the Z-axis direction and are arranged in a lattice pattern when viewed from the X-axis direction. Note that the communication paths 140b and the liquid injection ports 51 are not shown in FIG. 5 .

[0057] More specifically, in the energy storage device 100, the multiple energy storage modules 1 are stacked so that the direction in which the first liquid injection frame 50A protrudes from the sealing main body 140 (one side in the first direction) is vertically upward and the direction in which the second liquid injection frame 50B protrudes from the sealing main body 140 (the other side in the first direction) is vertically downward, and so that the first liquid injection frame 50A is arranged along the vertical direction and the second liquid injection frame 50B is arranged along the vertical direction.

[0058] Furthermore, when viewing adjacent energy storage modules 1, 1 in the vertical direction, the first liquid pouring frames 50A arranged in the stacking direction D have a gap between the lower end of the first liquid pouring frame 50A in one energy storage module 1 and the upper end of the first liquid pouring frame 50A in the other energy storage module 1. Furthermore, when viewing adjacent energy storage modules 1 in the vertical direction, the second liquid pouring frames 50B arranged in the stacking direction D have a gap between the lower end of the second liquid pouring frame 50B in one energy storage module 1 and the upper end of the second liquid pouring frame 50B in the other energy storage module 1. These two gaps are provided by adjusting the thickness of the conductive plate 7 arranged between adjacent energy storage modules 1, 1 in the stacking direction D. This makes it possible to prevent poor electrical contact between the modules and the conductive plate due to contact between the liquid pouring frames 53, 53 of adjacent modules in the stacking direction D.

[0059] Furthermore, in this energy storage device 100, when adjacent energy storage modules 1 in the stacking direction are viewed from the X-axis direction, the lower end of the second liquid pouring frame 50B of one energy storage module 1 is located lower than the upper end of the first liquid pouring frame 50A of the other energy storage module 1. As a result, due to the step between the first liquid pouring frame 50A and the second liquid pouring frame 50B in the stacking direction D, when one of the energy storage modules 1, 1 adjacent in the stacking direction D (Z-axis direction) moves laterally (in the Y-axis direction), a protruding portion of one energy storage module 1 comes into contact with a protruding portion of the other energy storage module 1. This makes it possible to restrict the energy storage modules 1, 1 from moving relative to each other in the Y-axis direction, which is perpendicular to the stacking direction D. In other words, this can be used for positioning when stacking the energy storage modules 1.

[0060] The effects of the energy storage module 1 and the energy storage device 100 of the above embodiment will be described. The energy storage device 100 of the above embodiment is configured by stacking a plurality of energy storage modules 1. In the energy storage module 1 of the present embodiment, the liquid injection frame 53 provided in the liquid injection section 50 for injecting the electrolyte solution 5 protrudes from the seal main body 140 in the Z-axis direction, which is the stacking direction D. However, the amount by which a portion of the liquid injection frame 53 protrudes upward in the Z-axis direction from the seal main body 140 is greater for the first liquid injection frame 50A than for the second liquid injection frame 50B, and the amount by which a portion of the liquid injection frame 53 protrudes downward in the Z-axis direction from the seal main body 140 is greater for the second liquid injection frame 50B than for the first liquid injection frame 50A. This prevents the portions that protrude significantly from the seal main body 140 from facing each other in the stacking direction D, thereby preventing the size of the energy storage device 100 from increasing in the stacking direction D when assembled.

[0061] In the energy storage module 1 of the above embodiment, the multiple liquid injection frames 53 are configured from a first liquid injection frame 50A, a portion of which protrudes from the seal main body 140 only upward in the Z-axis direction, and a second liquid injection frame 50B, a portion of which protrudes from the seal main body 140 only downward in the Z-axis direction. In other words, each of the first liquid injection frame 50A and the second liquid injection frame 50B of the above embodiment has one side (either the upper side or the lower side) in the Z-axis direction that does not protrude from the seal main body 140. This prevents the portions that significantly protrude from the seal main body 140 from facing each other in the stacking direction D, making it possible to prevent an increase in the size of the energy storage device 100 when assembled.

[0062] The energy storage module 1 of the above embodiment includes only a first liquid pouring frame 50A and a second liquid pouring frame 50B as the liquid pouring frame 53. This allows the configuration of the liquid pouring frame 53 to be limited to the configuration of the first liquid pouring frame 50A and the configuration of the second liquid pouring frame 50B, thereby improving the productivity of the energy storage module 1. Furthermore, the energy storage module 1 of the above embodiment is provided with the same number of first liquid pouring frames 50A and second liquid pouring frames 50B, ensuring symmetry and resulting in excellent balance when the energy storage modules 1 are stacked.

[0063] In the energy storage module 1 of the above embodiment, four side surfaces 140a are formed on the frame-shaped sealing portion 14, and the multiple liquid pouring frames 53 are formed on one of the side surfaces 140a and arranged along the Y-axis direction perpendicular to the stacking direction D, as shown in Figures 2 and 3. This makes it easier to pour the electrolyte solution 5, compared to an energy storage module 1 configured such that the liquid pouring frames 53 are formed in a distributed manner on the multiple side surfaces 140a.

[0064] 2 and 4, in the energy storage module 1 of the above embodiment, the first liquid pouring frames 50A are arranged continuously in the Y-axis direction, and the second liquid pouring frames 50B are also arranged continuously in the Y-axis direction. In this configuration, the step between the first liquid pouring frame 50A and the second liquid pouring frame 50B can prevent the energy storage modules 1, 1 adjacent to each other in the stacking direction D from moving relative to each other in the Y-axis direction.

[0065] In the energy storage module 1 of the above embodiment, metal sheet members 18 are attached to the frame-shaped first surface 14b and second surface 14c of the sealing portion 14, which are surfaces perpendicular to the stacking direction D and are arranged at both ends of the electrode stack 3. The metal sheet members 18 have a lower moisture permeability coefficient than resin, and therefore, moisture penetration into the sealing portion 14 is suppressed compared to when the sealing portion 14 is composed only of the sealing portion 14.

[0066] In the energy storage module 1 of the above embodiment, exposed surfaces 22e, 22e exposed to the outside are formed on the second surfaces 21b of the current collectors 21 constituting the positive electrodes 11 and the second surfaces 22b of the current collectors 22 constituting the negative electrodes 12, which are arranged at both ends of the electrode stack 3. In the energy storage module 1 configured in this manner, multiple energy storage modules 1 can be electrically connected in series simply by the simple operation of stacking the energy storage modules 1 with the conductive plates 7 placed on the exposed surfaces 22e.

[0067] Although one embodiment has been described above, the present invention is not limited to the above embodiment, and various modifications are possible without departing from the spirit of the invention.

[0068] In the above embodiment, as shown in FIG. 4, an example has been described in which the first liquid pouring frames 50A are arranged continuously in the Y-axis direction perpendicular to the stacking direction D, and the second liquid pouring frames 50B are arranged continuously in the Y-axis direction. However, the present invention is not limited to this. For example, in an energy storage module 1A according to a modified example, the first liquid pouring frames 50A and the second liquid pouring frames 50B may be arranged alternately in the Y-axis direction, as shown in FIG. 6. In a configuration of an energy storage device 100A in which energy storage modules 1 of this modified example are stacked, the second liquid pouring frame 50B fits into the step between the pair of first liquid pouring frames 50A, 50A, and the first liquid pouring frame 50A fits into the step between the pair of second liquid pouring frames 50B, 50B. This makes it possible to prevent the energy storage modules 1, 1 adjacent to each other in the stacking direction D from moving relative to each other in the Y-axis direction.

[0069] Although Figure 6 illustrates an example in which the metal sheet member 18 is not disposed, the metal sheet member 18 may be attached to the frame-shaped first surface 14b and second surface 14c formed on both ends of the electrode stack 3.

[0070] In the above embodiment and modified example, an example has been described in which only the first liquid injection frame 50A and the second liquid injection frame 50B are provided on the side surface 140a of the sealing portion 14. However, in addition to these liquid injection frames 53, for example, the liquid injection portion 50 may include a liquid injection frame 53 on both one and the other sides in the stacking direction D, in which a portion of the liquid injection frame 53 does not protrude from the sealing main body portion 140, or a liquid injection frame 53 on both one and the other sides in the stacking direction D, in which a portion of the liquid injection frame 53 protrudes from the sealing main body portion 140.

[0071] The number of liquid filling frames 53, the number of liquid filling ports 51 formed in one liquid filling frame 53, and the number and arrangement of first liquid filling frames 50A and second liquid filling frames 50B shown in the above embodiment and modified examples can be changed as appropriate in accordance with the number of internal spaces S formed in the energy storage module 1. For example, in an energy storage module 1 arranged so that the stacking direction D is along the vertical direction, only one liquid filling frame 53 forming a liquid filling port 51 corresponding to the communicating path 140b that communicates with the uppermost internal space S may be designated as the first liquid filling frame 50A, only one liquid filling frame 53 forming a liquid filling port 51 corresponding to the communicating path 140b that communicates with the lowermost internal space S may be designated as the second liquid filling frame 50B, and the remaining liquid filling frames 53 may be configured as third liquid filling frames that do not protrude in the stacking direction D from the seal main body 140.

[0072] In the above embodiment and the above modified example, an example has been given in which all of the liquid injection frames 53 are arranged on one side surface 140a among the multiple side surfaces 140a of the sealing portion 14, but this is not limited to this, and for example, multiple liquid injection frames 53 may be distributed and arranged on multiple side surfaces 140a.

[0073] The technical subject matter of one aspect of the present invention can be described as follows. [1] A storage module used in a stacked storage device, an electrode stack in which bipolar electrodes, each having a positive electrode formed on a first surface of a current collector and a negative electrode formed on a second surface opposite to the first surface, are stacked along a first direction; an internal space is formed between the current collectors adjacent to each other in the first direction, and a sealing portion is provided to seal the internal space; The sealing portion is a main body portion that is a cylindrical body formed in a rectangular frame shape so as to surround the electrode stack when viewed from the first direction, and that has a plurality of communication passages provided on one side surface of the cylindrical body that communicate with each of the plurality of internal spaces; a liquid injection section attached to the one side surface of the main body section and having a plurality of liquid injection ports communicating with the respective communication passages; The liquid injection section is a plurality of liquid filling frames each independently surrounding an end of a plurality of the communication paths arranged along the first direction to form the liquid filling port, the plurality of liquid filling frames being arranged on the one side surface of the main body in a second direction perpendicular to the first direction; the plurality of liquid filling frames arranged in the second direction include a first liquid filling frame in which a portion of the liquid filling frame protrudes from the main body portion at least on one side in the first direction, and a second liquid filling frame in which a portion of the liquid filling frame protrudes from the main body portion at least on the other side in the first direction, a protrusion amount of a part of the liquid filling frame protruding from the main body portion to one side in the first direction is greater for the first liquid filling frame than for the second liquid filling frame, a protrusion amount of a part of the second liquid filling frame from the main body portion to the other side in the first direction is greater than that of the first liquid filling frame. [2] a portion of the first liquid filling frame protrudes from the main body portion only on one side in the first direction; The energy storage module according to [1], wherein a part of the second liquid pouring frame protrudes from the main body only on the other side in the first direction. [3] a plurality of the first liquid filling frames and a plurality of the second liquid filling frames are provided, The energy storage module according to [1] or [2], wherein the first liquid filling frames are arranged continuously in the second direction, and the second liquid filling frames are arranged continuously in the second direction. [4] a plurality of the first liquid filling frames and a plurality of the second liquid filling frames are provided, The electricity storage module according to any one of [1] to [3], wherein the first liquid pouring frames and the second liquid pouring frames are arranged alternately in the second direction. [5] The energy storage module according to any one of [1] to [4], wherein the liquid injection section further has an overhang section that is connected to the main body section and that covers a portion of both end faces of the electrode stack in the first direction. [6] The electricity storage module according to any one of [1] to [5], wherein a laminate film that covers the liquid pouring port is attached to the liquid pouring frame. [7] In the laminate, when the positive electrode constituting one end of the laminate in the first direction is a terminal positive electrode and the negative electrode constituting the other end of the laminate in the first direction is a terminal negative electrode, The energy storage module according to any one of [1] to [6], wherein one surface of the current collector on which the positive electrode is not formed in the terminal positive electrode and one surface of the current collector on which the negative electrode is not formed in the terminal negative electrode have an exposed surface that is exposed to the outside. [8] A plurality of the storage modules according to [7] above; a conductive plate; The energy storage device, wherein the energy storage modules are stacked in the first direction via the conductive plates in contact with the exposed surfaces. [9] When the electricity storage modules are stacked so that the one side is vertically upward and the other side is vertically downward, and the first liquid pouring frame is arranged along the vertical direction and the second liquid pouring frame is arranged along the vertical direction, [8] The energy storage device according to [8], wherein, when the energy storage modules adjacent to each other in the vertical direction are viewed, a lower end of the second liquid pouring frame in one of the energy storage modules is positioned lower than an upper end of the first liquid pouring frame in the other energy storage module. [Explanation of symbols]

[0074] DESCRIPTION OF SYMBOLS 1,1A...energy storage module, 2...energy storage cell, 3...electrode stack, 5...electrolyte, 7...conductive plate, 11...positive electrode, 12...negative electrode, 14...sealing portion, 18...sheet member, 21...current collector, 21e...exposed surface, 22...current collector, 22e...exposed surface, 50...pouring portion, 50A...first pouring frame, 50B...second pouring frame, 51...pouring port, 53...pouring frame, 100,100A...energy storage device, 140...sealing main body portion (main body portion), 140a...side surface, 140b...communicating path, D...stacking direction (first direction), S...internal space

Claims

1. A storage module used in a stacked storage device, an electrode stack in which bipolar electrodes, each having a positive electrode formed on a first surface of a current collector and a negative electrode formed on a second surface opposite to the first surface, are stacked along a first direction; an internal space is formed between the current collectors adjacent to each other in the first direction, and a sealing portion is provided to seal the internal space; The sealing portion is a main body portion that is a cylindrical body formed in a rectangular frame shape so as to surround the electrode stack when viewed from the first direction, and that has a plurality of communication passages provided on one side surface of the cylindrical body that communicate with each of the plurality of internal spaces; a liquid injection section attached to the one side surface of the main body section and having a plurality of liquid injection ports communicating with the respective communication passages; The liquid injection section is a plurality of liquid filling frames each independently surrounding an end of a plurality of the communication paths arranged along the first direction to form the liquid filling port, the plurality of liquid filling frames being arranged on the one side surface of the main body in a second direction perpendicular to the first direction; the plurality of liquid filling frames arranged in the second direction include a first liquid filling frame in which a portion of the liquid filling frame protrudes from the main body portion at least on one side in the first direction, and a second liquid filling frame in which a portion of the liquid filling frame protrudes from the main body portion at least on the other side in the first direction, a protrusion amount of a part of the liquid filling frame protruding from the main body portion to one side in the first direction is greater for the first liquid filling frame than for the second liquid filling frame, a protrusion amount of a part of the second liquid filling frame from the main body portion to the other side in the first direction is greater than that of the first liquid filling frame.

2. a portion of the first liquid filling frame protrudes from the main body portion only on one side in the first direction; The electric storage module according to claim 1 , wherein a portion of the second liquid filling frame protrudes from the main body portion only on the other side in the first direction.

3. a plurality of the first liquid filling frames and a plurality of the second liquid filling frames are provided, 3. The electricity storage module according to claim 1, wherein the first liquid filling frames are arranged continuously in the second direction, and the second liquid filling frames are arranged continuously in the second direction.

4. a plurality of the first liquid filling frames and a plurality of the second liquid filling frames are provided, The electricity storage module according to claim 1 or 2, wherein the first liquid filling frames and the second liquid filling frames are arranged alternately in the second direction.

5. The energy storage module according to claim 1 or 2, wherein the liquid injection portion further includes an overhang portion connected to the main body portion and covering a portion of both end faces of the electrode stack in the first direction.

6. 3. The electricity storage module according to claim 1, wherein a laminate film covering the liquid pouring port is attached to the liquid pouring frame.

7. In the laminate, when the positive electrode constituting one end of the laminate in the first direction is a terminal positive electrode and the negative electrode constituting the other end of the laminate in the first direction is a terminal negative electrode, 3. The energy storage module according to claim 1, wherein one surface of the current collector on which the positive electrode is not formed in the terminal positive electrode and one surface of the current collector on which the negative electrode is not formed in the terminal negative electrode have an exposed surface that is exposed to the outside.

8. A plurality of the energy storage modules according to claim 7; a conductive plate; The energy storage device, wherein the energy storage modules are stacked in the first direction via the conductive plates in contact with the exposed surfaces.

9. When the electricity storage modules are stacked so that the one side is vertically upward and the other side is vertically downward, and the first liquid pouring frame is arranged along the vertical direction and the second liquid pouring frame is arranged along the vertical direction, 9. The energy storage device according to claim 8, wherein, when the energy storage modules adjacent to each other in the vertical direction are viewed, a lower end of the second liquid pouring frame in one of the energy storage modules is located lower than an upper end of the first liquid pouring frame in the other of the energy storage modules.

Images