Energy storage module

Abstract

This electric power storage module (X1) comprises: at least one flat secondary battery (1) having at least one power generation body (20), which includes a positive electrode material, a negative electrode material, and an electrolyte, and a first accommodation body (50) for accommodating therein the power generation body; and a housing for accommodating the at least one secondary battery. The first accommodation body has, at a portion of the outer edge section of the first accommodation body, a plurality of extending parts (11) which are flexible and fixed to the inner bottom surface (10a) of the housing in a state of being bent.

Description

Technical Field

[0001] The present disclosure relates to a power storage module.

Background Art

[0002] Patent Document 1 discloses an electrochemical cell module (power storage module) having a plurality of electrochemical cells and a housing that houses the plurality of electrochemical cells. In the electrochemical cell module, the electrochemical cell includes a power generation element and a packaging body. By bending the peripheral edge of the packaging body, the main surface of the peripheral edge is in contact with the inner surface of the housing.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

[0004] A power storage module according to one aspect of the present disclosure includes one or more power generation bodies including a positive electrode material, a negative electrode material, and an electrolyte, and a first housing that houses the power generation bodies, one or more power storage elements having a flat shape, and a housing that houses the one or more power storage elements, wherein the first housing has a plurality of extending portions that are flexible and fixed to the inner bottom surface of the housing in a bent state at a part of the outer edge portion of the first housing.

Brief Description of the Drawings

[0005]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Mode for Carrying Out the Invention

[0006] (Structure of Power Storage Module X1) FIG. 1 is a perspective view showing the appearance of a power storage module X1 according to the present disclosure. FIG. 2 is a cross-sectional view taken along line II-II in FIG. 1. As shown in FIG. 1, the power storage module X1 includes a housing 6. Further, as shown in FIG. 2, the power storage module X1 further includes a plurality of secondary batteries 1 (power storage elements) housed inside the housing 6. However, the power storage module X1 may include only one secondary battery 1.

[0007] (Structure of Secondary Battery 1) The secondary battery 1 functions as a battery within the power storage module X1. The secondary battery 1 may be, for example, a lithium-ion battery. The secondary battery 1 may have a flat shape having a main surface and a side surface. As shown in FIG. 2, the secondary batteries 1 are housed inside the housing 6 with their main surfaces facing each other.

[0008] FIG. 3 is a perspective view showing the appearance of the secondary battery 1. The secondary battery 1 may include a power generation body 20, connection terminals 21 and 22, and a first container 50.

[0009] The power generation body 20 stores and discharges electricity using an electrochemical reaction. The power generation body 20 includes, for example, a positive electrode material, a negative electrode material, and an electrolyte. For simplicity, only one power generation body 20 is shown in FIG. 3. However, the secondary battery 1 may include a plurality of power generation bodies 20. Specific examples of the power generation body 20 will be described later with reference to FIG. 4.

[0010] The first container 50 may accommodate the power generator 20. The first container 50 may be formed of, for example, an aluminum pouch film or a laminate film having a metal foil layer such as stainless steel or nickel. The aluminum pouch film may be a film obtained by vapor-depositing aluminum on the film or a film obtained by laminating an aluminum foil and a film. The material of the film may be, for example, polypropylene, polyethylene, nylon, or polyethylene terephthalate. The thickness of the first container 50 may be 50 μm or more and 300 μm or less, and may be, for example, 200 μm.

[0011] When the first container 50 is an aluminum pouch film, the first container 50 may have a configuration in which two aluminum pouch films are located on both sides in the stacking direction (Z-axis direction) of the power generator 20. Further, when the first container 50 is an aluminum pouch film, the first container 50 may have a configuration in which one aluminum pouch film is folded in half and the power generator 20 is located inside.

[0012] The connection terminals 21 and 22 may be terminals for taking out power from the secondary battery 1 or supplying power to the secondary battery 1. The connection terminals 21 and 22 may protrude from the inside to the outside of the first container 50. The material of the connection terminals 21 and 22 may be, for example, copper, aluminum, or nickel. The thickness of the connection terminals 21 and 22 may be 50 μm or more and 500 μm or less, and may be, for example, 200 μm. Further, the connection terminals 21 and 22 may be subjected to a surface treatment for improving the adhesiveness with an adhesive member (not shown). The adhesive member adheres the connection terminals 21 and 22 and the first container 50 located above and below the connection terminals 21 and 22 to determine the positions of the connection terminals 21 and 22 with respect to the first container 50.

[0013] The first container 50 has side portions 51. The side portions 51 are the portions that are adhered to the side plates 9 of the housing 6 described later. The side portions 51 are flexible. Also, the first container 50 has a first extension portion 111 and a second extension portion 112 on the opposite side of the connection terminals 21 and 22. The first extension portion 111 and the second extension portion 112 are the portions that are adhered to the bottom plate 10 of the housing 6 described later. The first extension portion 111 and the second extension portion 112 are flexible. The first extension portion 111 and the second extension portion 112 are adjacent to each other and are spaced apart. In the following description, when it is not necessary to distinguish between the first extension portion 111 and the second extension portion 112 from each other, they are collectively referred to as the extension portion 11.

[0014] Also, the first container 50 may have a first notch portion 113 between the first extension portion 111 and the second extension portion 112. Also, the first container 50 may have a second notch portion 114 at each of (i) the end of the first extension portion 111 on the side opposite to the second extension portion 112 and (ii) the end of the second extension portion 112 on the side opposite to the first extension portion 111.

[0015] In FIG. 3, the first extension portion 111 and the second extension portion 112 are symmetric with respect to the center line CL of the first container 50 and are spaced apart from the end of the first container 50. However, the positions of the first extension portion 111 and the second extension portion 112 are not limited to this. For example, the first extension portion 111 and the second extension portion 112 may not be spaced apart from each other. Also, for example, at least one of the first extension portion 111 and the second extension portion 112 may not be spaced apart from the end of the first container 50.

[0016] Also, the power storage module X1 may further include an extension portion 11 other than the first extension portion 111 and the second extension portion 112. Also in this case, each of the plurality of extension portions 11 may be in contact, or at least two of the plurality of extension portions 11 may be spaced apart from each other. Also, the extension portion 11 located at the end of the first container 50 in the X direction or the -X direction among the plurality of extension portions 11 may be in contact with or spaced apart from the end.

[0017] FIG. 4 is a perspective view showing the appearance of the power generation body 20 included in the secondary battery 1. As shown in FIG. 4, the power generation body 20 may have a sheet-like shape. The sheet-like power generation body 20 may include a positive electrode 23 and a negative electrode 24.

[0018] The secondary battery 1 may further include a second container 15 that individually houses the power generation body 20. If there is one power generation body 20 included in the secondary battery 1, there is also one second container 15 that houses the power generation body 20. If there are a plurality of power generation bodies 20 included in the secondary battery 1, there are also a plurality of second containers 15 that house the power generation bodies 20. When a plurality of second containers 15 that house the power generation body 20 are stacked, the plurality of second containers 15 may be adhered to each other by an adhesive layer (not shown). The material of the second container 15 may be, for example, a film-like PET (polyethylene terephthalate) or nylon. More specifically, for example, two second containers 15 may have a configuration located on both sides in the stacking direction (Z-axis direction) of the power generation body 20. The thickness of the base material of the second container 15 may be, for example, 10 μm or more and 40 μm or less, and may be, for example, 25 μm. The material of the adhesive layer may be, for example, polypropylene or polyethylene.

[0019] The second container 15 may be, for example, transparent. FIG. 4 is a diagram showing a state in which the power generation body 20 can be confirmed through the second container 15 by using the transparent second container 15 for the power generation body 20.

[0020] The second container 15 may have a notch 16. For example, a notch 16 may be provided in each of the second container 15 on the positive electrode 23 side and the second container 15 on the negative electrode 24 side. By providing the notch 16 as a portion that is not sealed in a part of the power generation body 20, gas generated by the decomposition reaction of the electrolytic solution or a small amount of moisture inside the power generation body 20 can be released to the outside of the power generation body 20.

[0021] The positive electrode 23 may have an exposed portion 23e that is exposed from the second container 15. The negative electrode 24 may have an exposed portion 24e that is exposed from the second container 15. The connection terminals 21 and 22 may be electrically connected to the exposed portions 23e and 24e, respectively, by, for example, ultrasonic welding, laser welding, or resistance welding.

[0022] The secondary battery 1 may have a configuration in which a plurality of power generation elements 20 are individually housed in the second container 15, and the plurality of power generation elements 20 in the state of being housed in the second container 15 are further housed in the first container 50. By having this configuration, since the power generation elements 20 are doubly housed, the safety of the secondary battery 1 can be enhanced. Also, the first container 50 may be housed in a further container. However, the secondary battery 1 only needs to include the power generation elements 20 and only needs to be housed by at least one container.

[0023] The secondary battery 1 has a configuration in which a plurality of power generation elements 20 are stacked, and for example, has a configuration in which 10 layers of power generation elements 20 are stacked. However, the secondary battery 1 according to the present disclosure may include a plurality of layers different from 10 layers of the power generation elements 20, or may include only 1 layer. When the secondary battery 1 includes a plurality of layers of the power generation elements 20, those power generation elements 20 may be laminated. When the secondary battery 1 shown in FIG. 3 is viewed in plan, the portion excluding the connection terminals 21 and 22 may be substantially rectangular, or may have a different shape. Also, when the power generation element 20 shown in FIG. 4 is viewed in plan, the portion excluding the exposed portions 23e and 24e may be substantially rectangular, or may have a different shape.

[0024] The positive electrode material may be a mixture of a positive electrode active material and a conductive assistant. Also, the negative electrode material may be a mixture of a negative electrode active material and a conductive assistant. The positive electrode active material may be, for example, lithium cobaltate, lithium nickelate, lithium iron phosphate, or lithium manganate. The negative electrode active material may be, for example, graphite or lithium titanate. The conductive assistant may be, for example, carbon black or acetylene black. However, the positive electrode active material, the negative electrode active material, and the conductive assistant are not limited to these.

[0025] The positive electrode material may have a so-called clay-like property, which is a mixture composed of a positive electrode active material and a conductive assistant with an electrolytic solution mixed therein. The negative electrode material may have a so-called clay-like property, which is a mixture composed of a negative electrode active material and a conductive assistant with an electrolytic solution mixed therein. The positive electrode 23 may be an electrode in which the positive electrode material is coated on an aluminum foil. The negative electrode 24 may be an electrode in which the negative electrode material is coated on a copper foil.

[0026] The electrolytic solution is obtained by dissolving a lithium salt, which is an electrolyte, in a non-aqueous solvent. As the non-aqueous solvent, a carbonate-based solvent may be used. As the carbonate-based solvent, γ-butyrolactone may be used, ethylene carbonate may be used, or both γ-butyrolactone and ethylene carbonate may be used. Also, as long as the carbonate-based solvent contains at least one of γ-butyrolactone and ethylene carbonate, it may contain other solvents. Examples of other solvents include propylene carbonate, dimethyl carbonate, dimethoxyethane, diethyl carbonate, tetrahydrofuran, and triethylene glycol dimethyl ether. As the electrolyte, lithium hexafluorophosphate or lithium bis(fluorosulfonyl)imide (LiFSI) may be used.

[0027] Also, the power generation body 20 may further include a separator. In that case, the power generation body 20 may have a structure in which the positive electrode 23 and the negative electrode 24 are laminated via the separator. The separator may function as an insulating member that insulates the positive electrode 23 and the negative electrode 24. For the separator, for example, a sheet-like non-woven fabric or a porous material may be used.

[0028] The positive electrode material and the negative electrode material do not necessarily have a clay-like property. In this case, the electrolytic solution does not necessarily need to be mixed into the positive electrode active material and the negative electrode active material. Also in this case, the inside of the power generation body 20 is filled with the electrolytic solution, and the electrolytic solution may be impregnated and held in the separator.

[0029] (Structure of the housing 6) The housing 6 has a space for accommodating a plurality of secondary batteries 1. The housing 6 protects the secondary batteries 1 from the external environment. Specifically, the housing 6 protects the secondary batteries 1 from external forces received from the external environment. The housing 6 may be, for example, in the shape of a rectangular parallelepiped box.

[0030] The housing 6 may have, for example, two main panels 8, two side panels 9, a bottom panel 10, and a terminal cover 7. The terminal cover 7 is provided to protect the connection terminals 21, 22 of the secondary battery 1. The main panel 8 is provided to protect the main surface of the secondary battery 1. The side panel 9 is provided to protect the side surface of the secondary battery 1.

[0031] FIG. 5 is an enlarged view of the region V in FIG. 2. As shown in FIG. 5, a part of the side portion 51 of the first container 50 may be adhered to the side panel 9 in a bent state. The side portion 51 of the first container 50 on the side opposite to the side shown in FIG. 5 may be adhered to the opposite side panel 9. In the present embodiment, the secondary battery 1 is mainly held in the housing 6 by the connection portion between the side portion 51 of the first container 50 and the side panel 9. Therefore, from the viewpoint of dispersing the weight of the secondary battery 1 applied to the connection portion between the side portion 51 and the side panel 9, the entire side portion 51 in the direction along the outer edge of the first container 50 may be adhered to the side panel 9.

[0032] (Connection portion between the extension portion 11 and the bottom panel 10 of the housing 6) FIG. 6 is a cross-sectional view showing the structure of the connection portion between the extension portion 11 and the bottom panel 10 of the power storage module X1. In the power storage module X1, the flexible extension portion 11 is fixed to the inner bottom surface 10a, which is the inner surface of the bottom panel 10 of the housing 6, in a bent state.

[0033] As described above, the extension part 11 is a general term for the first extension part 111 and the second extension part 112. In the power storage module X1, the secondary battery 1 may be deformed due to the expansion and contraction of the secondary battery 1 or the vibration of the power storage module X1. In the power storage module X1, when the secondary battery 1 is deformed, the first extension part 111 and the second extension part 112 are deformed individually, so that the stress on the secondary battery 1 due to the deformation can be relaxed.

[0034] Specifically, the extension part 11 may include a non-fixed part 11a and a fixed part 11b. The non-fixed part 11a is a part of the first container 50 that is at least partially curved and located at the lower end of the power generation body 20. The fixed part 11b is a part of the extension part 11 that is connected to the non-fixed part 11a, faces the inner bottom surface 10a, and is at least partially fixed to the inner bottom surface 10a. The fixed part 11b is fixed by being adhered to the inner bottom surface 10a via the adhesive layer 10b. The adhesive layer 10b is a layer of adhesive located on the inner bottom surface 10a. There is no particular limitation on the adhesive used as the material of the adhesive layer 10b, and known adhesives can be used.

[0035] By providing the fixed part 11b on the extension part 11, the secondary battery 1 can be fixed to the inner bottom surface 10a. Also, by providing the non-fixed part 11a on the extension part 11, when the secondary battery 1 is deformed, the non-fixed part 11a is deformed, so that the stress caused by the deformation of the secondary battery 1 can be relaxed.

[0036] Furthermore, an air layer 13 exists between the secondary battery 1 and the inner bottom surface 10a (at the location where the extension part 11 exists in the power storage module X1). Since at least a part of the non-fixed part 11a is curved, the area of the extension part 11 in contact with the air layer 13 increases compared to the case where the non-fixed part 11a is not curved. Therefore, the heat generated in the secondary battery 1 can be easily released from the extension part 11 to the outside.

[0037] As shown in FIG. 6, a part of the non-fixed portion 11a may overlap with the fixed portion 11b of another secondary battery 1 adjacent to the secondary battery 1 having the non-fixed portion 11a. In FIG. 6, a vicinity portion 11c near the boundary portion between the non-fixed portion 11a and the fixed portion 11b overlaps with the fixed portion 11b of another secondary battery 1 adjacent to the secondary battery 1 having the non-fixed portion 11a. The vicinity portion 11c is a part of the non-fixed portion 11a and has a shape continuous with the fixed portion 11b. Since the vicinity portion 11c overlaps with the fixed portion 11b of another secondary battery 1, it is not fixed to the inner bottom surface 10a.

[0038] In the example shown in FIG. 6, the length of the non-fixed portion 11a becomes longer compared to the case where the vicinity portion 11c does not overlap with the fixed portion 11b of another secondary battery 1. By having such a length of the non-fixed portion 11a, when deformation occurs in the secondary battery 1, it becomes easier to relieve stress. The non-fixed portion 11a may overlap with the fixed portion 11b of another secondary battery 1 adjacent to the secondary battery 1 having the non-fixed portion 11a in a wider range than the example shown in FIG. 6.

[0039] FIG. 7 is a cross-sectional view taken along line VII-VII in FIG. 6. The line VII-VII in FIG. 6 is along the boundary between two adjacent first containers 50. For this reason, in FIG. 7, the surface rather than the cross-section of the first container 50 appears. As shown in FIG. 7, the power storage module X1 may have a first space portion 121. The first space portion 121 is a space between a first extension portion 111 and a second extension portion 112 that communicates in the direction perpendicular to the main surface of the secondary battery 1 (the direction perpendicular to the paper surface in FIG. 7), that is, the Z direction, across the plurality of secondary batteries 1 in a state where the power storage module X1 includes the plurality of secondary batteries 1 whose main surfaces face each other.

[0040] For example, when all the secondary batteries 1 have the same shape as each other, the first space portion 121 communicates across all the secondary batteries 1. However, in the power storage module X1, it is not necessarily required that all the secondary batteries 1 have the same shape as each other. Even in that case, at least two adjacent secondary batteries 1 may have a shape in which the first space portion 121 communicates.

[0041] Specifically, as described above, the first container 50 may have a first notch portion 113 between the first extension portion 111 and the second extension portion 112. Therefore, a first space portion 121 is formed between the first notch portion 113 and the bottom plate 10 at a location where the first notch portion 113 communicates.

[0042] Since the power storage module X1 has the first space portion 121, air easily flows through the first space portion 121 inside the power storage module X1. Therefore, the temperature inside the power storage module X1 is likely to be uniformized.

[0043] Also, as shown in FIG. 7, the power storage module X1 may have a second space portion 122. The second space portion 122 is a space between at least one of the first extension portion 111 and the second extension portion 112 and the inner surface 9a of the side plate 9 of the housing 6 that communicates across a plurality of secondary batteries 1 provided in the power storage module X1 with their main surfaces facing each other.

[0044] For example, when all the secondary batteries 1 have the same shape as each other, the second space portion 122 communicates across all the secondary batteries 1. However, as described above, in the power storage module X1, not necessarily all the secondary batteries 1 have to have the same shape as each other. Even in that case, at least two adjacent secondary batteries 1 may have a shape in which the second space portion 122 communicates.

[0045] Specifically, as described above, the first container 50 may have a second notch portion 114 at each of (i) the end of the first extension portion 111 on the side opposite to the second extension portion 112 and (ii) the end of the second extension portion 112 on the side opposite to the first extension portion 111. Therefore, a second space portion 122 is formed between the second notch portion 114, the bottom plate 10, and the side plate 9 at a location where the second notch portion 114 communicates.

[0046] Since the power storage module X1 has the second space portion 122, air easily flows through the second space portion 122 inside the power storage module X1. Therefore, the temperature inside the power storage module X1 is likely to be uniformized.

[0047] The power storage module X1 does not necessarily have to have both the first space portion 121 and the second space portion 122. Even when the power storage module X1 has only one of the first space portion 121 and the second space portion 122, air easily flows inside the power storage module X1 through the said one. However, when the power storage module X1 has both the first space portion 121 and the second space portion 122, air more easily flows inside the power storage module X1.

[0048] Also, the power storage module X1 does not necessarily have to have the second space portion 122 both between (i) the first extension portion 111 and the side plate 9 and (ii) the second extension portion 112 and the side plate 9, and may have the second space portion 122 only in one of them. However, when the power storage module X1 has the second space portion 122 in both of the above, air more easily flows inside the power storage module X1.

[0049] Also, when the secondary battery 1 has at least one of the first notch portion 113 and the second notch portion 114, in the power storage module X1, the length of the adhesion portion between the inner bottom surface 10a and the first housing 50 in the direction parallel to the main surface of the secondary battery 1 is shorter than the case where the entire outer edge portion of the first housing 50 facing the inner bottom surface 10a is adhered to the inner bottom surface 10a. For this reason, in the power storage module X1, the weight of the secondary battery 1 per unit length of the adhesion portion between the first housing 50 and the inner bottom surface 10a is larger than the case where the entire outer edge portion of the first housing 50 facing the inner bottom surface 10a is adhered to the inner bottom surface 10a.

[0050] However, as described above, in the power storage module X1, the secondary battery 1 is held in the housing 6 mainly by the connection portion between the side portion 51 of the first container 50 and the side plate 9. In other words, the weight of the secondary battery 1 applied to the extending portion 11 is smaller compared to the weight of the secondary battery 1 applied to the side portion 51. Therefore, in the power storage module X1, the possibility that the adhesion between the inner bottom surface 10a and the first container 50 is disengaged due to the weight of the secondary battery 1 being applied to the extending portion 11 is negligibly small.

[0051] The lengths of the first extending portion 111 and the second extending portion 112 in the direction parallel to the inner bottom surface 10a may be 1 mm to 20 mm. By the lengths of the first extending portion 111 and the second extending portion 112 being within such a range, the stability of the secondary battery 1 in the housing 6 can be improved, and the stress against the deformation of the secondary battery 1 can be relieved. Also, the lengths of the first extending portion 111 and the second extending portion 112 in the direction parallel to the inner bottom surface 10a may be equal to each other or different from each other.

[0052] Also, as shown in FIG. 7, in the power storage module X1, only a part of each of the portions of the first extending portion 111 and the second extending portion 112 facing the inner bottom surface 10a may be fixed by being adhered to the inner bottom surface 10a via the adhesive layer 10b. When the extending portion 11 is fixed to the inner bottom surface 10a in this way, a gap will exist between the portion of the extending portion 11 that is not adhered to the inner bottom surface 10a via the adhesive layer 10b and the inner bottom surface 10a. Therefore, air easily flows through the gap between the extending portion 11 and the inner bottom surface 10a inside the power storage module X1. Thus, the temperature inside the power storage module X1 is easily equalized.

[0053] Specifically, in the power storage module X1, only both ends of each of the plurality of extending portions 11, which face the inner bottom surface 10a, may be fixed by being adhered to the inner bottom surface 10a via the adhesive layer 10b. When the extending portion 11 is fixed to the inner bottom surface 10a in this manner, gaps other than both ends exist in the portion where the extending portion 11 and the inner bottom surface 10a face each other, and air can easily flow through the gaps. Also, by reducing the area of the extending portion 11 adhered to the inner bottom surface 10a, the amount of adhesive used can be saved. Furthermore, by adhering both ends of the extending portion 11 to the inner bottom surface 10a, the possibility of the adhesion coming off can be reduced.

[0054] An example of a method for fixing the extending portion 11 to the inner bottom surface 10a by the adhesive layer 10b is shown below. First, the adhesive is disposed on the inner bottom surface 10a along a straight line passing through positions corresponding to both ends of the plurality of extending portions 11 when the plurality of secondary batteries 1 are accommodated in the housing 6 parallel to the side plate 9. Next, the plurality of secondary batteries 1 are accommodated in the housing 6 such that both ends of the extending portion 11 in the bent state are in contact with the adhesive disposed on the inner bottom surface 10a. In that state, by solidifying the adhesive to form the adhesive layer 10b, only both ends of the extending portion 11 of the plurality of secondary batteries 1 are fixed by being adhered to the inner bottom surface 10a via the adhesive layer 10b.

[0055] The thickness of the adhesive layer 10b may be 0.1 mm or more. By setting the thickness of the adhesive layer 10b in this way, a gap large enough for air to flow exists between the portion of the extending portion 11 that is not adhered to the inner bottom surface 10a via the adhesive layer 10b and the inner bottom surface 10a.

[0056] FIG. 8 is a diagram showing the bending position of the extension portion 11 in the secondary battery 1. In FIG. 8, the dashed-dotted line L1 indicates the bending position where the extension portion 11 is bent when the secondary battery 1 is housed in the housing 6 of the power storage module X1. FIG. 8 is a diagram with a partial perspective view of the inside of the secondary battery 1 for explaining the positions of the power generation body 20, the second housing 15, etc. The bending position may be outside the second housing 15. The bending position in FIG. 8 is on the boundary line between the extension portion 11 and the portion other than the extension portion 11. However, the bending position of the extension portion 11 in the secondary battery 1 is not limited to this.

[0057] In this case, even when the extension portion 11 is bent, the second housing 15 is not bent inside the first housing 50. Also, in FIG. 8, the dashed-dotted line L2 indicates the bending position where the side portion 51 is bent when the secondary battery 1 is housed in the housing 6 of the power storage module X1. The bending position where the side portion 51 is bent may also be outside the second housing 15.

[0058] When the bending positions of the extension portion 11 and the side portion 51 in the secondary battery 1 are not outside the second housing 15, the second housing 15 is also in a bent state when the extension portion 11 is bent. In this case, there is no space in the plane view of the main surface of the secondary battery 1 between the first housing 50 and the second housing 15 of the secondary battery 1 housed in the housing 6. For this reason, when gas is generated inside the secondary battery 1, the pressure inside the secondary battery 1 increases due to the gas, and the secondary battery 1 may rupture.

[0059] On one hand, in the power storage module X1, the extension part 11 and the side part 51 are bent outside the second container 15, so that there is a space between the first container 50 and the second container 15 of the secondary battery 1 housed in the housing 6 when the main surface of the secondary battery 1 is viewed in plan. When gas is generated inside the secondary battery 1, the space expands toward the front and the back sides of the paper in FIG. 8, alleviating the increase in the internal pressure of the secondary battery 1 caused by the gas. Therefore, in the power storage module X1, the possibility of the secondary battery 1 bursting due to the gas generated inside the secondary battery 1 is reduced as compared with the case where the bending positions of the extension part 11 and the side part 51 are not outside the second container 15.

[0060] 〔Supplementary Notes〕 As described above, the invention according to the present disclosure has been described based on the drawings and the embodiments. However, the invention according to the present disclosure is not limited to the above-described embodiments. That is, the invention according to the present disclosure can be variously modified within the scope shown in the present disclosure, and embodiments obtained by appropriately combining the technical means disclosed in different embodiments are also included in the technical scope of the invention according to the present disclosure. It should be noted that those skilled in the art can easily make various deformations or modifications based on the present disclosure. Also, note that these deformations or modifications are included in the scope of the present disclosure.

Explanation of Reference Numerals

[0061] 1 Secondary battery (power storage element) 6 Housing 10a Inner bottom surface 10b Adhesive layer 11 Extension part 11a Non-fixed part 11b Fixed part 111 First extension part 112 Second extension part 121 First space part 122 Second space part 20 Power generation body 15 Second container 50 First container X1 Power storage module

Claims

1. One or more power generation bodies including a positive electrode material, a negative electrode material, and an electrolyte, and a first container housing the power generation body, and one or more power storage elements having a flat shape, A housing that houses the one or more power storage elements, The first container has a plurality of extending portions that are flexible at a part of the outer edge portion of the first container and are fixed to the inner bottom surface of the housing in a bent state. The power storage module.

2. Each of the plurality of extending portions A non-fixed portion in which at least a part is curved, A fixed portion that is connected to the non-fixed portion, faces the inner bottom surface, and at least a part is fixed to the inner bottom surface. The power storage module according to claim 1.

3. There are a plurality of the power storage elements, A part of the non-fixed portion overlaps with a fixed portion of a first container included in another power storage element adjacent to the power storage element including the first container having the non-fixed portion. The power storage module according to claim 2.

4. The plurality of extending portions have a first extending portion and a second extending portion that are adjacent to each other and spaced apart from each other at the outer edge portion of the power storage element, In a state where the power storage module includes the plurality of power storage elements whose main surfaces face each other, the power storage module has a first space portion in which a space between the first extending portion and the second extending portion communicates across the plurality of power storage elements. The power storage module according to any one of claims 1 to 3.

5. The plurality of extending portions have a first extending portion and a second extending portion that are adjacent to each other and spaced apart from each other at the outer edge portion of the power storage element, In a state where the power storage module includes the plurality of power storage elements whose main surfaces face each other, the power storage module has a second space portion in which a space between at least one of the first extending portion and the second extending portion and the inner side surface of the housing communicates across the plurality of power storage elements. The power storage module according to any one of claims 1 to 4.

6. Only a part of the portion of each of the plurality of extending portions facing the inner bottom surface is fixed by being adhered to the inner bottom surface via an adhesive layer that is an adhesive layer located on the inner bottom surface. The power storage module according to any one of claims 1 to 5.

7. The power storage module according to claim 6, wherein only both ends of a part of each of the plurality of extended parts, which faces the inner bottom surface, are fixed by being adhered to the inner bottom surface via the adhesive layer.

8. The power storage element further includes one or a plurality of second containers that house the power generation body. The first container houses the second container. The power storage module according to any one of claims 1 to 7, wherein a position where each of the plurality of extended parts is bent is outside the second container.

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