Storage container

Abstract

To provide a storage container which reduces the thickness of a panel and achieves reduction in the weight and the cost, and has performances in fire resistance and fire retardant property equal to or higher than those of a box using a thick steel plate in the panel.SOLUTION: A storage container 100 includes a bottom face part 1, a top face part 2, and a plurality of side face parts 3A to 3D, wherein at least one of the bottom face part 1, the top face part 2, and the plurality of side face parts 3A to 3D includes such a composite panel that steel flat plates 15, 23, and 33 and steel wavy plates 16, 24, and 34 are joined to each other.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present disclosure relates to a storage container including a composite panel of a flat plate and a corrugated plate.

Background Art

[0002] For example, the electrolyte contained in a lithium-ion battery has a risk of catching fire like petroleum products. Therefore, there is a risk of a fire due to ignition of the lithium-ion battery. When storing and handling substances with a fire risk such as lithium-ion batteries, safety measures are necessary so that in the event of a fire, it does not spread to the surroundings. As a safety measure, it has been conventionally practiced to store a lithium-ion battery or the like in a box-shaped storage container having fire resistance and fire prevention properties made of a thick steel plate.

Prior Art Documents

Non-Patent Documents

[0003]

Non-Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, a storage container in which thick steel plates are used for the panels of the bottom surface portion, the top surface portion, and each side surface portion has a large weight and is difficult to handle, and there is a problem that the material cost is high because the thickness of the steel plate is large.

[0005] An object of the present disclosure is to solve the above problems, and to provide a storage container that has a reduced panel thickness to achieve weight reduction and low cost, and has performance equivalent to or better than that when using a thick steel plate for the panel in terms of fire resistance and fire prevention.

Means for Solving the Problems

[0006] In order to solve the above problems, the storage container of the present disclosure includes, as the subject, the storage container described in Item 1 below.

[0007] Item 1. A storage container comprising a bottom surface portion and a top surface portion arranged opposite to each other, and a plurality of side surface portions erected along a plurality of sides of the bottom surface portion and the top surface portion between the bottom surface portion and the top surface portion. The storage container, wherein at least one of the bottom surface portion, the top surface portion, and the plurality of side surface portions includes a composite panel in which a steel flat plate and a steel corrugated plate are joined.

[0008] Further, the storage container of the present disclosure includes, as a preferred embodiment of the storage container described in Item 1 above, the storage container described in Item 2 below.

[0009] Item 2. The bottom surface portion, the top surface portion, and the plurality of side surface portions include a frame-shaped frame and a panel fitted into the frame. The storage container according to Item 1, wherein the frame includes a support surface on which an outer peripheral edge portion of the fitted panel is overlapped.

[0010] Further, the storage container of the present disclosure includes, as a preferred embodiment of the storage container described in Item 1 or Item 2 above, the storage container described in Item 3 below.

[0011] Item 3. The storage container according to Item 1 or 2, wherein two adjacent side surface portions of the plurality of side surface portions are connected by fitting a convex portion formed at a lateral end portion of one side surface portion into a concave groove formed at a lateral end portion of the other side surface portion.

[0012] Further, the storage container of the present disclosure includes, as a preferred embodiment of the storage container described in any one of Items 1 to 3 above, the storage container described in Item 4 below.

[0013] Item 4. The storage container according to any one of Items 1 to 3, wherein one of the top surface portion and the plurality of side surface portions is such that the panel is removable from the frame to form an entrance / exit for the stored item.

[0014] In addition, the storage container of the present disclosure includes the storage container described in the following item 5 as a preferred embodiment of the storage container according to any one of items 1 to 4 above.

[0015] Item 5. The storage container according to any one of claims 1 to 4, in which a lithium-ion battery is stored.

Advantages of the Invention

[0016] According to the storage container of the present disclosure, since the side surface portion, the top surface portion, and the panels of each side surface portion are composite panels combining a flat plate and a corrugated plate, it is possible to reduce the thickness of the panel to achieve weight reduction and cost reduction, and to have fire resistance and fireproof performance equal to or higher than those in the case where a steel plate with a large thickness is used for the panel.

Brief Description of the Drawings

[0017]

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MODE FOR CARRYING OUT THE INVENTION

[0018] Hereinafter, embodiments of the storage container of the present disclosure will be described with reference to the accompanying drawings.

[0019] <Overview of the storage container> FIGS. 1 to 7 show a storage container 100 according to an embodiment of the present disclosure. The storage container 100 is a container for storing substances having a fire hazard, such as flammable liquids (referred to as "flammable hazardous substances" in the present disclosure). Examples of flammable hazardous substances include, but are not particularly limited to, lithium-ion batteries and battery facilities using lithium-ion batteries.

[0020] The storage container 100 has a box shape including a bottom surface portion 1, a top surface portion 2 disposed opposite to the bottom surface portion 1, and a plurality of side surface portions 3 erected between the bottom surface portion 1 and the top surface portion 2. The plurality of side surface portions 3 are connected in a square tube shape and are respectively arranged along a plurality of sides of the bottom surface portion 1 and the top surface portion 2. In the present embodiment, the bottom surface portion 1 and the top surface portion have a rectangular shape in plan view, and the four side surface portions 3 on the front, rear, left, and right are respectively arranged along the four sides of the bottom surface portion 1 and the top surface portion 2.

[0021] The bottom surface portion 1, the top surface portion 2, and the plurality of side surface portions 3 are each composed of a frame and a panel attached to the frame. One of the top surface portion 2 and the plurality of side surface portions 3 is detachable, allowing the panel to be easily removed from the frame. By removing the panel from the frame, an entrance / exit is formed in the storage container 100 through which items can be put into and taken out of the internal space of the storage container 100. In the present embodiment, among the four side surface portions 3, as shown in FIG. 8, the front side panel 36 can be removed from the front side frame 35 on the front side surface portion 3D on the front side.

[0022] Next, each component of the storage container 100 will be described. In the following description, "inside" refers to the internal space side of the storage container 100, and "outside" refers to the external space side of the storage container 100, which is the opposite side of the inside.

[0023] <Configuration of the bottom surface portion> As shown in FIGS. 9 to 12, the bottom surface portion 1 includes a bottom surface frame 10, a bottom surface panel 11, and a plurality of leg members 12. In the present embodiment, the bottom surface portion 1 includes four leg members 12.

[0024] The bottom surface frame 10 has a rectangular frame shape in plan view. The bottom surface frame 10 is formed by combining four frame members 13A - 13D in a rectangular shape. Each of the frame members 13A - 13D has an "F" shape in cross-sectional view, as shown in FIGS. 12(A) to (D). Steel materials are used for each of the frame members 13A - 13D. In the present embodiment, each of the frame members 13A - 13D is composed of a combination of a first steel material 17 and a second steel material 18.

[0025] The first steel material 17 of each of the frame members 13A - 13D has a "U" shape in cross-sectional view, and includes an elongated plate-shaped bottom wall 133 and a pair of elongated plate-shaped opposing side walls 131, 132 (hereinafter, the outer side wall 131 is referred to as the "first side wall 131" and the inner side wall 132 is referred to as the "second side wall 132") that stand upright from the opposing long sides of the bottom wall 133. In the first steel material 17, a concave groove 130 (hereinafter referred to as the "concave groove 130") is formed between the first side wall 131 and the second side wall 132.

[0026] The second steel material 18 of each of the frame materials 13A-13D is generally flat or "L" shaped in cross section, and has a horizontal support wall 180 that is wider than the bottom wall 133 of the first steel material 17. The second steel material 18 has the bottom wall 133 of the first steel material 17 joined to the upper surface of the support wall 180 by, for example, welding or bolts. As a result, the second steel material 18 is integrated with the first steel material 17 such that a portion of the support wall 180 protrudes inward from the bottom wall 133 of the first steel material 17.

[0027] The bottom frame 10 is arranged so that the recessed grooves 130 of each of the frame materials 13A-13D face upward. A portion of the lower end side of each of the four side surface portions 3 is fitted into the recessed grooves 130 of each of the frame materials 13A-13D. The four side surface portions 3 are erected on the bottom frame 10 by being fitted into the recessed grooves 130 of each of the frame materials 13A-13D.

[0028] The legs 12 have a length extending from one of a pair of opposing frame members 13C, 13D of the bottom frame 10 to the other. Steel is used for the legs 12. The legs 12 are generally U-shaped or U-shaped in cross section, and are attached to the bottom frame 10 with a concave groove 120 (hereinafter referred to as the "concave groove 120") facing upward, as shown in FIG. 12(E). Each leg 12 has a flange 122 that protrudes horizontally outward from the upper end of a pair of opposing side walls 121 that sandwich the concave groove 120. The pair of opposing frame members 13C, 13D of the bottom frame 10 are joined to the upper surface of the flange 122 of each leg 12 by, for example, welding or bolts. Further, the two legs 12 at both ends have a pair of opposing frame members 13A, 13B of the bottom frame 10 joined to the upper surfaces of the flanges 122 by, for example, welding or bolts.

[0029] As shown in Fig. 10, the bottom frame 10 has a surrounding wall presenting a rectangular shape in plan view formed by combining the second side walls 132 of the first steel materials 17 of the respective frame members 13A - 13D in a rectangular shape. Further, in the support wall 180 of the second steel material 18 of each frame member 13A - 13D, the bottom frame 10 has a support surface presenting a rectangular shape in plan view formed inside the surrounding wall by combining the portions protruding inward from the second side wall 132 of the first steel material 17 in a rectangular shape.

[0030] As shown in Fig. 9, the bottom panel 11 is fitted inside the surrounding wall of the bottom frame 10. The bottom panel 11 attached to the bottom frame 10 has its outer peripheral edge in contact with the support surface of the bottom frame 10 and is joined by, for example, welding or bolts. Thus, the bottom panel 11 is integrated with the bottom frame 20.

[0031] Since the outer peripheral edge of the bottom panel 11 is overlapped with the support surface of the bottom frame 10, the joint portion between the bottom frame 10 and the bottom panel 11 is blocked. Thereby, the bottom part 1 can block the fire from passing through the joint of the bottom frame 230 and the bottom panel 11 and prevent the fire from spreading between the inside and outside of the storage container 100.

[0032] As shown in Fig. 9, the bottom panel 11 presents a rectangular shape in plan view. As shown in Fig. 11, the bottom panel 11 is a composite panel including a flat steel plate 15 and a corrugated steel plate 16. The flat plate 15 is a flat plate with both sides being flat. The corrugated plate 16 is a concavo - convex plate (corrugated plate) with both sides being curved in a wave shape, and is a plate in which concavities (valleys) and convexities (peaks) are continuously arranged in one direction. The corrugated plate 16 is formed, for example, by processing a flat plate into a wave shape. The flat plate 15 and the corrugated plate 16 are of the same size and shape. The thicknesses of the flat plate 15 and the corrugated plate 16 may be the same or different. The bottom of each concavity (valley) of the corrugated plate 16 is joined to one surface of the flat plate 15 by, for example, welding or bolts, so that the flat plate 15 and the corrugated plate 16 are integrated. The bottom panel 11 is arranged with the corrugated plate 16 on the upper side and the flat plate 15 on the lower side, but the flat plate 15 and the corrugated plate 16 may be arranged in the reverse order.

[0033] The flat plate 15 and the corrugated plate 16 may each be formed of a single plate material, or for example, two plate materials may be joined at their respective ends by, for example, welding, bolts, etc. to form a single unit.

[0034] The shape of the concave (valley) and convex (peak) in the corrugated plate 16 is not particularly limited, and in a cross-sectional view, various shapes such as, for example, an arc shape, a triangular shape, a square shape, a trapezoidal shape, etc. can be adopted.

[0035] As shown in FIG. 13, the thickness (plate thickness) t of the corrugated plate 16 is not particularly limited, but from the viewpoint of the strength of the panel, it is preferably 0.25 mm or more, and more preferably 0.35 mm or more. On the other hand, the thickness (plate thickness) t of the corrugated plate 16 is preferably 0.7 mm or less, and more preferably 0.5 mm or less from the viewpoint of weight reduction of the panel.

[0036] In addition, when storing a lithium-ion battery (including the "battery equipment" using a lithium-ion battery) in the storage container 100, in the current operation of storing and handling lithium-ion batteries, in the event of a fire, it does not spread to the surroundings. Therefore, it is required to store the lithium-ion battery in a box made of a steel plate with a thickness of 1.6 mm or more or a material having performance equivalent thereto and having no openings other than the entrance (limited to those made of a steel plate with a thickness of 1.6 mm or more or a material having performance equivalent thereto). Therefore, when storing the lithium-ion battery in the storage container 100, the thickness (plate thickness) t of the corrugated plate 16 is preferably 0.35 mm or more.

[0037] The thickness (plate thickness) T of the flat plate 15 is not particularly limited, but from the viewpoint of the strength of the panel, it is preferably 0.25 mm or more, and more preferably 0.35 mm or more. On the other hand, from the viewpoint of weight reduction of the panel, the thickness (plate thickness) T of the flat plate 15 is preferably 0.7 mm or less, and more preferably 0.5 mm or less. When the lithium-ion storage battery is stored in the storage container 100, the thickness (plate thickness) T of the flat plate 15 is preferably 0.35 mm or more.

[0038] <Configuration of the side surface portion> (1) Left side surface portion, right side surface portion, and rear side surface portion Among the four side surface portions 3, the left left side surface portion 3A on the left side, the right right side surface portion 3B on the right side, and the rear rear side surface portion C on the rear side include a side surface frame 30 and a side surface panel 31 as shown in FIGS. 14 to 17.

[0039] The side surface frame 30 has a rectangular frame shape in plan view. The side surface frame 30 is formed by combining four frame members 32A - 32D in a rectangular shape. Steel materials are used for the four frame members 32A - 32D.

[0040] As shown in FIG. 17(A), the upper frame member 32A has a "C" - shaped or "U" - shaped cross - section, and includes an elongated plate - shaped upper wall 323 and a pair of elongated plate - shaped opposing side walls 321, 322 (hereinafter, the outer side wall 321 is referred to as the "first side wall 321" and the inner side wall 322 is referred to as the "second side wall 322") that hang down from the opposing long sides of the upper wall 323. In the upper frame member 32A, a concave groove 320 (hereinafter referred to as the "concave groove 320") is formed between the first side wall 321 and the second side wall 322. The upper frame member 32A is arranged such that the concave groove 320 faces downward.

[0041] As shown in FIG. 17(B), the lower frame member 32B has an "L" - shaped cross - section and includes an elongated plate - shaped bottom wall 324 and a side wall 325 that are orthogonal to each other.

[0042] The two frame members 32C and 32D on both sides are in a substantially "C" shape or a substantially "U" shape in cross-section as shown in FIGS. 17(C) and 17(D), and include a pair of elongated plate-shaped proximal walls 328 and distal walls 329 facing each other, an elongated plate-shaped first side wall 327 connecting the outer long sides of the proximal wall 328 and the distal wall 329, and a second side wall 330 protruding horizontally from the inner long side of the proximal wall 328 toward the side opposite to the distal wall 329 side. In the two frame members 32C and 32D on both sides, the first side wall 327, the proximal wall 328, and the distal wall 329 form a convex portion 332 protruding laterally from the side panel 31. Further, in the two frame members 32C and 32D on both sides, a concave groove 326 (hereinafter referred to as "concave groove 326") is formed between the proximal wall 328 and the distal wall 329. The two frame members 32C and 32D on both sides are arranged with the concave groove 326 facing inward.

[0043] As shown in FIG. 15, for the upper frame member 32A, both ends of the second side wall 322 are overlapped with the outer surfaces of the second side walls 330 of the two frame members 32C and 32D on both sides and joined by, for example, welding or bolts. For the lower frame member 32B, both ends of the side wall 325 are overlapped with the outer surfaces of the second side walls 330 of the two frame members 32C and 32D on both sides and joined by, for example, welding or bolts. Thereby, the four frame members 32A - 32D are combined in a rectangular shape.

[0044] The side frame 30 forms a surrounding wall in a rectangular shape in plan view when the upper wall 323 of the upper frame member 32A, the proximal walls 328 of the frame members 32C and 32D on both sides, and the bottom wall 324 of the lower frame member 32B are combined in a rectangular shape. Further, the side frame 30 forms a support surface in a rectangular shape in plan view inside the surrounding wall when the second side wall 322 of the upper frame member 32A, the side wall 325 of the lower frame member 32B, and the second side walls 330 of the frame members 32C and 32D on both sides are combined in a rectangular shape.

[0045] The side panel 31 is fitted inside the surrounding wall of the side frame 30 while a part of the upper end side is fitted into the concave groove 320 of the upper frame member 32A. The side panel 31 attached to the side frame 30 has its outer peripheral edge in contact with the support surface of the side frame 30 and is joined by, for example, welding or bolts. Thus, the side panel 31 is integrated with the side frame 30.

[0046] Since the outer peripheral edge of the side panel 31 is overlapped with the support surface of the side frame 30, the joint portion between the side frame 30 and the side panel 31 is blocked. Thus, the side portions 3A - 3C can block the fire from passing through the joint of the side frame 30 and the side panel 31 and prevent the fire from spreading between the inside and outside of the storage container 100.

[0047] As shown in FIG. 16, through holes 331 are formed in the upper wall 323 of the upper frame member 32A near both ends in the length direction. In this embodiment, the through holes 331 are in the form of elongated slits.

[0048] As shown in FIGS. 14 and 16, the side panel 31 has a rectangular shape in plan view. The inner surface of the side panel 31 is flat, and items to be stored are stored inside the side panel 31. The side panel 31 is a composite panel including a flat steel plate 33 and a corrugated steel plate 34. The flat plate 33 is a flat plate with both sides being flat. The corrugated plate 34 is a concavo - convex plate (corrugated plate) with both sides being curved in a wave shape, and is a plate in which concaves (valleys) and convexes (peaks) are arranged continuously in one direction. The corrugated plate 34 is formed, for example, by processing a flat plate into a wave shape. The flat plate 33 and the corrugated plate 34 have the same size and shape. The thicknesses of the flat plate 33 and the corrugated plate 34 may be the same or different. The flat plate 33 and the corrugated plate 34 are integrated by joining the bottom of each concave (valley) of the corrugated plate 34 to one surface of the flat plate 33 by, for example, welding or bolts. The side panel 31 is arranged with the corrugated plate 34 on the outside and the flat plate 33 on the inside, but the flat plate 33 and the corrugated plate 34 may be arranged in the reverse order.

[0049] The flat plate 33 and the corrugated plate 34 may each be formed of a single plate material, or for example, two plate materials may be joined at their respective ends by, for example, welding or bolts to form a single unit.

[0050] The shape of the concave (valley) and convex (peak) portions of the corrugated plate 34 is not particularly limited, and in a cross-sectional view, it can be formed into various shapes such as, for example, an arc shape, a triangular shape, a rectangular shape, a trapezoidal shape, etc.

[0051] The thickness (plate thickness) of the corrugated plate 34 is not particularly limited, but from the viewpoint of the strength of the panel, it is preferably 0.25 mm or more, and more preferably 0.35 mm or more. On the other hand, from the viewpoint of weight reduction of the panel, the thickness (plate thickness) of the corrugated plate 34 is preferably 0.7 mm or less, and more preferably 0.5 mm or less. When a lithium-ion battery is housed in the storage container 100, the thickness (plate thickness) of the corrugated plate 34 is preferably 0.35 mm or more, similar to the bottom panel 11.

[0052] The thickness (plate thickness) of the flat plate 33 is not particularly limited, but from the viewpoint of the strength of the panel, it is preferably 0.25 mm or more, and more preferably 0.35 mm or more. On the other hand, from the viewpoint of weight reduction of the panel, the thickness (plate thickness) of the flat plate 33 is preferably 0.7 mm or less, and more preferably 0.5 mm or less. When a lithium-ion battery is housed in the storage container 100, the thickness (plate thickness) of the flat plate 33 is preferably 0.35 mm or more, similar to the bottom panel 11.

[0053] (2) Front side surface portion Among the four side surface portions 3, the front side surface portion 3D on the front side includes a front side frame 35 and a front side panel 36 as shown in FIGS. 18 and 21.

[0054] As shown in FIGS. 18 to 20, the front side frame 35 has a rectangular frame shape in plan view. The front side frame 35 is formed by combining four frame members 37A - 37D in a rectangular shape. Steel materials are used for the four frame members 37A - 37D. The upper frame member 37A is composed of a combination of a first steel material 38 and a second steel material 39.

[0055] As shown in FIG. 20(A), the first steel material 38 of the upper frame member 37A has an elongated plate - shaped upper wall 383 presenting a "C" - shaped or "U" - shaped cross - section, and a pair of elongated plate - shaped side walls 381, 382 (hereinafter, the outer side wall 381 is referred to as the "first side wall 381", and the inner side wall 382 is referred to as the "second side wall 382") hanging down from the opposing long sides of the upper wall 383. In the first steel material 38, a concave groove 380 (hereinafter referred to as the "concave groove 380") is formed between the first side wall 381 and the second side wall 382. The first steel material 38 is arranged with the concave groove 380 facing downward.

[0056] As shown in FIG. 20(A), the second steel material 39 of the upper frame member 37A presents a substantially "Z" - shaped cross - section, and includes an elongated plate - shaped horizontal wall 390, a first side wall 391 standing upright from the outer long side of the horizontal wall 390, and a second side wall 392 hanging down from the inner long side of the horizontal wall 390. The second steel material 39 is joined to the first steel material 38 such that the first side wall 391 is overlapped with the inner surface of the first side wall 381 of the first steel material 38 and joined by, for example, welding or bolts, and the second side wall 392 is overlapped with the outer surface of the second side wall 382 of the first steel material 38 and joined by, for example, welding or bolts. Thereby, the second steel material 39 is integrated with the first steel material 38 such that the horizontal wall 390 covers the concave groove 380 of the first steel material 38.

[0057] As shown in FIG. 20(B), the lower frame member 37B presents an "L" - shaped cross - section and includes an elongated plate - shaped bottom wall 370 and a side wall 371 that are orthogonal to each other.

[0058] The two frame members 37C and 37D on both sides are, as shown in FIGS. 20(C) and 20(D), substantially "C"-shaped or substantially "U"-shaped in cross-section, and include a pair of elongated plate-shaped proximal walls 374 and distal walls 375 facing each other, an elongated plate-shaped first side wall 373 connecting the outer long sides of the proximal wall 374 and the distal wall 375, and a second side wall 376 protruding horizontally from the inner long side of the proximal wall 374 toward the side opposite to the distal wall 375 side. In the two frame members 37C and 37D on both sides, the first side wall 373, the proximal wall 374, and the distal wall 375 form a convex portion 384 protruding laterally from the front panel 36. Further, in the two frame members 37C and 37D on both sides, a concave groove 372 (hereinafter referred to as "concave groove 372") is formed between the proximal wall 374 and the distal wall 375. The two frame members 37C and 37D on both sides are arranged with the concave groove 372 facing inward.

[0059] As shown in FIG. 18, for the upper frame member 37A, both ends of the second side wall 382 of the first steel member 38 are overlapped with the outer surfaces of the second side walls 376 of the two frame members 37C and 37D on both sides and joined by, for example, welding or bolts. For the lower frame member 37B, both ends of the side wall 371 are overlapped with the outer surfaces of the second side walls 376 of the two frame members 37C and 37D on both sides and joined by, for example, welding or bolts. Thereby, the four frame members 37A - 37D are combined in a rectangular shape.

[0060] The front side frame 35 forms a surrounding wall having a rectangular shape in plan view by combining the horizontal wall 390 of the second steel member 39 of the upper frame member 37A, the proximal walls 374 of the frame members 37C and 37D on both sides, and the bottom wall 370 of the lower frame member 37B in a rectangular shape. Further, the front side frame 35 forms a support surface having a rectangular shape in plan view inside the surrounding wall by combining the second side walls 382 and 392 of the upper frame member 37A, the side wall 371 of the lower frame member 37B, and the second side walls 376 of the frame members 37C and 37D on both sides in a rectangular shape.

[0061] The front side panel 36 is fitted inside the surrounding wall of the front side frame 35. The front side panel 36 attached to the front side frame 35 has its outer peripheral edge in contact with the support surface of the front side frame 35.

[0062] Since the outer peripheral edge of the front side panel 36 is overlapped with the support surface of the front side frame 35, the joint portion between the front side frame 35 and the front side panel 36 is blocked. As a result, the 3D front side portion can block the fire from passing through the joint between the front side frame 35 and the front side panel 36 and prevent the fire from spreading inside and outside the storage container 100.

[0063] In the upper frame member 37A, through holes 377 are formed in the upper wall 383 of the first steel material 38 near both ends in the length direction as shown in FIG. 19. In this embodiment, the through holes 377 are in the shape of elongated slits.

[0064] As shown in FIGS. 21 and 23, the front side panel 36 has a rectangular shape in plan view. The front side panel 36 includes a panel body 40 having a rectangular shape in plan view and a frame body 41 to which the panel body 40 is attached.

[0065] The panel body 40 is composed of an upper panel portion and a lower panel portion. The lower panel portion is a composite panel including a flat steel plate 33 and a corrugated steel plate 34, similar to the side panels 31 of the left side surface portions 3A, 3B, and the rear side surface portion C. The flat plate 33 and the corrugated plate 34 of the front side panel 36 are smaller in size than the flat plate 33 and the corrugated plate 34 of the side panels 31 of the other side surface portions 3A - 3C. The upper panel portion is composed of a flat steel plate 42 whose upper end portion is bent in an "L" shape in cross-section view toward the outside. The thickness (plate thickness) of the steel plate 42 is not particularly limited, but when a lithium-ion battery is stored in the storage container 100, for example, it is 1.6 mm or more. The steel plate 42 is integrated with the lower panel portion by being joined to the upper end portion of the inner surface of the flat plate 33 constituting the lower panel portion by, for example, welding or bolts.

[0066] On the outer surface of the steel plate 42 of the upper panel portion, a fixing member 45 is attached near the lower end. The fixing member 45 is made of steel. As shown in Fig. 24(A), the fixing member 45 has a "Z" shape in cross-section, and includes an elongated plate-like horizontal wall 450, a first side wall 451 hanging down from the outer long side of the horizontal wall 450, and a second side wall 452 standing upright from the inner long side of the horizontal wall 450. The fixing member 45 is integrated with the steel plate 42 by overlapping the second side wall 452 on the outer surface of the steel plate 42 and joining it by, for example, welding or bolts. As a result, a concave groove 453 (hereinafter referred to as "concave groove 453") is formed between the steel plate 42 and the first side wall 451 of the fixing member 45 in the upper panel portion of the panel body 40. A part of the upper end side of the flat plate 33 and the corrugated plate 34 of the lower panel portion is fitted into the concave groove 453 of the upper panel portion.

[0067] As shown in Figs. 22 and 23, the frame body 41 is a combination of three fixing members 43, 44A, and 44B in a "C" shape in plan view. The three fixing members 43, 44A, and 44B are made of steel.

[0068] As shown in Fig. 24(B), the lower fixing member 43 has a substantially "C" shape or "U" shape in cross-section, and includes an elongated plate-like bottom wall 431 and a pair of elongated plate-like opposing side walls 432 and 433 (hereinafter, the outer side wall 432 is referred to as "first side wall 432" and the inner side wall 433 is referred to as "second side wall 433") standing upright from the opposing long sides of the bottom wall 431. In the lower fixing member 43, a concave groove 430 (hereinafter referred to as "concave groove 430") is formed between the first side wall 432 and the second side wall 433. The lower fixing member 43 is arranged with the concave groove 430 facing upward.

[0069] The two fixing members 44A and 44B on both sides are in a substantially "C" shape or a substantially "U" shape in cross-section as shown in FIGS. 24(C) and (D), and include a pair of elongated plate-shaped proximal walls 441 and distal walls 442 facing each other, an elongated plate-shaped first side wall 443 connecting the outer long sides of the proximal wall 441 and the distal wall 442, and a second side wall 444 protruding horizontally from the inner long side of the proximal wall 441 toward the side opposite to the distal wall 442 side. In the two fixing members 44A and 44B on both sides, a concave groove 440 (hereinafter referred to as "concave groove 440") is formed between the proximal wall 441 and the distal wall 442. The two fixing members 44A and 44B on both sides are arranged with the concave groove 440 facing inward.

[0070] As shown in FIG. 22, at the lower fixing member 43, both ends of the second side wall 433 are overlapped with the outer surfaces of the second side walls 444 of the two fixing members 44A and 44B on both sides and joined by, for example, welding or bolts. Thereby, the three fixing members 43, 44A, and 44B are combined in a "C" shape.

[0071] A part of the lower end side of the panel body 40 is fitted into the concave groove 430 of the lower fixing member 43 of the frame body 41, and the outer peripheral edge portion is overlapped with the outer surfaces of the second side wall 433 of the lower fixing member 43 of the frame body 41 and the outer surfaces of the second side walls 444 of the two fixing members 44A and 44B on both sides and joined by, for example, welding or bolts. Thereby, the panel body 40 is integrated with the frame body 41.

[0072] Since the outer peripheral edge portion of the panel body 40 is overlapped with the "C" shaped support surface composed of the three second side walls 433, 444, and 444 of the frame body 41, the joint portion between the frame body 41 and the panel body 40 is blocked. Thereby, the front side panel 36 can block the fire from passing through the joint between the frame body 41 and the panel body 40 and prevent the fire from burning from the inside to the outside of the storage container 100.

[0073] The front panel 36 can be easily removed (detachable) from the front frame 35 by, for example, holding the handle portion 420 (the portion bent in an L shape of the steel plate 42) of the upper panel portion of the panel body 40 shown in FIGS. 21 and 23 with the hand and pulling it forward after being attached to the front frame 35.

[0074] In the panel body 40 of the front panel 36, as shown in FIGS. 21 and 23, a plurality of reinforcing members 46 are joined to the upper panel portion by, for example, welding or bolts. Steel materials are used for the plurality of reinforcing members 46. The plurality of reinforcing members 46 reinforce the steel plate 42 by extending between the handle portion 420 and the horizontal wall 450 of the fixing member 45 in the upper panel portion. The front panel 36 can be removed from the front frame 35 by pulling the upper panel portion forward, and in this case, deformation of the steel plate 42 of the upper panel portion is suppressed by the plurality of reinforcing members 46.

[0075] In the panel body 40 of the front panel 36, as shown in FIGS. 21 and 23, lock members 47 are joined to both ends in the longitudinal direction of the upper panel portion by, for example, bolts or rivets. The lock members 47 regulate the removal of the front panel 36 from the front frame 35. In this embodiment, the lock members 47 include rod-shaped members 470 that are slidable in the lateral direction.

[0076] In the frame body 41 of the front panel 36, as shown in FIG. 23, through holes 445 are formed in the proximal walls 441 of the two fixing members 44A and 44B on both sides near the upper ends. The through holes 445 are circular in shape through which the rod-shaped members 470 can be inserted.

[0077] In the front frame 35, as shown in FIG. 19, through holes 378 are formed in the proximal walls 374 of the two frame members 37C and 37D on both sides near the upper ends. In this embodiment, the through holes 378 are oval-shaped.

[0078] When the front side panel 36 is attached to the front side frame 35, the through-hole 378 of the front side frame 35 shown in FIG. 19 and the through-hole 445 of the front side panel 36 shown in FIG. 23 are horizontally adjacent and continuous. Therefore, by sliding the rod-shaped member 470 of the lock member 47 and inserting it into the through-hole 445 of the front side panel 36 and the through-hole 378 of the front side frame 35, the front side panel 36 is fixed to the front side frame 35, and the removal of the front side panel 36 is restricted.

[0079] <Configuration of the top surface portion> As shown in FIGS. 25 to 28, the top surface portion 2 includes a top surface frame 20 and a top surface panel 21.

[0080] The top surface frame 20 has a rectangular frame shape in plan view. The top surface frame 20 is formed by combining four frame members 22A - 22D in a rectangular shape. Steel materials are used for each of the frame members 22A - 22D. As shown in FIGS. 28(A) to (D), each of the frame members 22A - 22D has a substantially "Z" - shaped or substantially "C" - shaped cross - section, and includes an elongated plate - shaped bottom wall 220, a side wall 221 that stands upright from the outer long side of the bottom wall 220, and an upper wall 222 that protrudes horizontally outward from the upper end of the side wall 221.

[0081] As shown in FIG. 26, for a pair of opposing frame members 22A and 22B among the four frame members 22A - 22D, both ends of their bottom walls 220 are overlapped on the upper surfaces of the bottom walls 220 of the other pair of opposing frame members 22C and 22D, and are joined by, for example, welding or bolts. Thus, the four frame members 22A - 22D are combined in a rectangular shape.

[0082] The top surface frame 20 forms a surrounding wall with a rectangular shape in plan view when the side walls 221 of the four frame members 22A - 22D are combined in a rectangular shape. Also, the top surface frame 20 forms a support surface with a rectangular shape in plan view inside the surrounding wall when the bottom walls 220 of the four frame members 22A - 22D are combined in a rectangular shape.

[0083] As shown in FIG. 25, the top panel 21 is fitted inside the surrounding wall of the top frame 20. The top panel 21 attached to the top frame 20 has its outer peripheral edge in contact with the support surface of the top frame 20 and is joined by, for example, welding or bolts. As a result, the top panel 21 is integrated with the top frame 20.

[0084] Since the outer peripheral edge of the top panel 21 is overlapped with the support surface of the top frame 20, the joint portion between the top frame 20 and the top panel 21 is blocked. As a result, the top surface portion 2 can block the fire from passing through the joint between the top frame 20 and the top panel 21 and prevent the fire from spreading inside and outside the storage container 100.

[0085] As shown in FIGS. 25 to 27, through holes 223 are formed in the upper walls 222 of the four frame members 22A - 22D of the top frame 20 near both ends in the length direction. In this embodiment, the through holes 223 are in the form of elongated slits.

[0086] As shown in FIGS. 25 and 27, the top panel 21 is rectangular in plan view. The lower surface of the top panel 21 is flat, and storage items are stored below the top panel 21. The top panel 21 is a composite panel including a flat steel plate 23 and a corrugated steel plate 24. The flat plate 23 is a flat plate with flat surfaces on both sides. The corrugated plate 24 is a concavo - convex plate (corrugated plate) with both surfaces curved in a wave shape, and is a plate in which concavities (valleys) and convexities (peaks) are arranged continuously in one direction. The corrugated plate 24 is formed, for example, by processing a flat plate into a wave shape. The flat plate 23 and the corrugated plate 24 are of the same size and shape. The thicknesses of the flat plate 23 and the corrugated plate 24 may be the same or different. The flat plate 23 and the corrugated plate 24 are integrated by joining the bottom of each concavity (valley) of the corrugated plate 24 to one surface of the flat plate 23 by, for example, welding or bolts. The top panel 21 is arranged with the corrugated plate 24 on the upper side and the flat plate 23 on the lower side, but the flat plate 23 and the corrugated plate 24 may be arranged in the reverse order.

[0087] The flat plate 23 and the corrugated plate 24 may each be formed of a single sheet of plate material, or for example, two sheets of plate material may be joined at their respective ends by, for example, welding or bolts to form a single unit.

[0088] The shape of the concave (valley) and convex (peak) in the corrugated plate 24 is not particularly limited, and in a cross-sectional view, it can be formed into various shapes such as, for example, an arc shape, a triangular shape, a quadrangular shape, a trapezoidal shape, etc.

[0089] The thickness (plate thickness) of the corrugated plate 24 is not particularly limited, but from the viewpoint of the strength of the panel, it is preferably 0.25 mm or more, and more preferably 0.35 mm or more. On the other hand, from the viewpoint of reducing the weight of the panel, the thickness (plate thickness) of the corrugated plate 24 is preferably 0.7 mm or less, and more preferably 0.5 mm or less. When the lithium ion battery is stored in the storage container 100, the thickness (plate thickness) of the corrugated plate 24 is preferably 0.35 mm or more.

[0090] The thickness (plate thickness) of the flat plate 23 is not particularly limited, but from the viewpoint of the strength of the panel, it is preferably 0.25 mm or more, and more preferably 0.35 mm or more. On the other hand, from the viewpoint of reducing the weight of the panel, the thickness (plate thickness) of the flat plate 23 is preferably 0.7 mm or less, and more preferably 0.5 mm or less. When the lithium ion battery is stored in the storage container 100, the thickness (plate thickness) of the flat plate 23 is preferably 0.35 mm or more.

[0091] <Method for assembling the storage container> Next, a method for assembling the storage container 100 described above will be explained. First, as shown in Fig. 29, place the bottom surface portion 1 on the floor or the like with the leg members 12 facing downward. Next, as shown in Fig. 30, for the left side surface portion 3A and the right side surface portion 3B among the four side surface portions 3A - 3D, while fitting a part of the lower end side into the concave groove 130 of the bottom surface portion 1, stand them up on the bottom surface portion 1. Next, as shown in Fig. 31, for the rear side surface portion 3C and the front side surface portion 3D, while fitting a part of the lower end side into the concave groove 130 of the bottom surface portion 1, stand them up on the bottom surface portion 1. At this time, as shown in Fig. 32, fit the other frame member 32D of the two frame members 32C, 32D on both sides of the left side surface portion 3C into the concave grooves 372 of the two frame members 37C, 37D on both sides of the front side surface portion 3D, and fit the other frame member 32C of the two frame members 32C, 32D on both sides of the right side surface portion 3D into the concave grooves 372 of the two frame members 37C, 37D on both sides of the front side surface portion 3D. Similarly, as shown in Fig. 33, fit one frame member 32C of the two frame members 32C, 32D on both sides of the left side surface portion 3C into the concave grooves 326 of the two frame members 32C, 32D on both sides of the rear side surface portion 3C, and fit one frame member 32D of the two frame members 32C, 32D on both sides of the right side surface portion 3D into the concave grooves 326 of the two frame members 32C, 32D on both sides of the rear side surface portion 3C. Thereby, the four side surface portions 3A - 3D are connected.

[0092] For example, at the connecting portion of the front side face 3D and the right side face 3B, as shown in FIG. 32, the convex portion 332 of the side frame member 32C on the right side face 3B is fitted into the concave groove 372 of the side frame member 37D on the side of the front side face 3D, and the frame members are overlapped with each other. Also, at the connecting portion of the rear side face 3C and the left side face 3A, as shown in FIG. 33, the convex portion 332 of the side frame member 32C on the side of the left side face 3A is fitted into the concave groove 326 of the side frame member 32D on the side of the rear side face 3C, and the frame members are overlapped with each other. In this way, at the connecting portion of the rear side face 3C and the left side face 3A and the connecting portion of the front side face 3D and the right side face 3B, the convex portion formed at the lateral end of one of the two adjacent side faces is fitted into the concave groove formed at the lateral end of the other side face and is in close contact therewith, so that the joint portion is blocked. Therefore, it is possible to block the fire from passing through the joint and the fire from spreading from the inside to the outside of the storage container 100. The same applies to the connecting portion of the rear side face 3C and the right side face 3B and the connecting portion of the front side face 3D and the left side face 3A.

[0093] Next, as shown in FIG. 34, the top face 2 is placed over the four side faces 3A - 3D. At this time, the top face frame 20 of the top face 2 is placed on the side face frames 30, 35 of the four side faces 3A - 3D. The through holes 331, 377 formed in the upper frame members 32A, 37A of the respective side face frames 30, 35 and the through hole 223 formed in the top face frame 20 are adjacent and continuous in the vertical direction.

[0094] Finally, as shown in FIG. 1, the connecting members 5 are attached to the four corners of the top face 2. A steel plate is used for the connecting member 5. As shown in FIG. 2, the connecting member 5 includes a covering portion 50 having a right - angled triangular shape in plan view. Guide portions 51 bent at a right angle downward are provided on two orthogonal sides of the covering portion 50, and insertion portions 52 bent at a right angle downward are provided inside the guide portions 51.

[0095] Attach the four connecting members 5 by placing the covering portion 50 on top of the top surface frame 20 and inserting the insertion portion 52 into the through holes 223 formed in each of the frame members 22A - 22D of the top surface frame 20 and the through holes 331, 377 formed in each of the side surface frames 30, 35 of the four side portions 3A - 3D. In this way, the top surface portion 2 and the four side portions 3A - 3D are connected.

[0096] <Function and Effect of the Storage Container> The storage container 100 of the present embodiment described above includes a bottom surface portion 1 and a top surface portion 2 arranged opposite to each other, and a plurality of side portions 3A - 3D erected along a plurality of sides of the bottom surface portion 1 and the top surface portion 2 between the bottom surface portion 1 and the top surface portion 2. The bottom surface portion 1, the top surface portion 2, and the plurality of side portions 3A - 3D are characterized by including composite panels in which corrugated steel plates 16, 24, 34 with continuous concavities and convexities arranged side by side on one surface of flat steel plates 15, 23, 33 made of steel are joined.

[0097] The storage container 100 of the present embodiment includes composite panels in which the panels 11, 21, 31 of the bottom surface portion 1, the top surface portion 2, and the plurality of side portions 3A - 3C, and the panel body 40 of the front side portion 3D are combined with flat steel plates 15, 23, 33 made of steel and corrugated steel plates 16, 24, 34 made of steel. Thus, the total thickness of the panels (the sum of the thickness of the flat plate and the thickness of the corrugated plate) can be made smaller than that of a steel plate having equivalent fire resistance, fireproofness, and heat resistance.

[0098] Therefore, according to the storage container 100 of the present embodiment, while reducing the total thickness of the panels to improve the ease of handling and reduce costs by reducing the weight of the storage container 100, it is possible to achieve performance equivalent to or better than that of a box made of a thick steel plate in terms of fire resistance, fireproofness, and heat resistance.

[0099] By making each of the panels 11, 21, 31, 36 a composite panel that combines, for example, flat plates 15, 23, 33 made of steel with a thickness of 0.35 mm or more and corrugated plates 16, 24, 34 made of steel with a thickness of 0.35 mm or more, each of the panels 11, 21, 31, 36 has fire resistance, fireproofness, and heat resistance equal to or greater than that of a steel plate with a thickness of 1.6 mm or more. Therefore, when a lithium-ion battery is housed in the housing container 100, even if the lithium-ion battery catches fire, it is possible to suppress the fire from spreading outside and inside the housing container 100 and spreading to the surrounding objects of the housing container 100, and even when a fire occurs around the housing container 100, it is possible to suppress the fire from spreading outside and inside the housing container 100 and spreading to the lithium-ion battery. Thus, it is possible to safely house a lithium-ion battery or the like having a fire hazard.

[0100] <Modification example> As described above, one embodiment of the housing container of the present disclosure has been described. However, the housing container of the present disclosure is not limited to the above embodiment, and various modifications can be made without departing from the spirit of the present disclosure.

[0101] For example, regarding the bottom panel 11 of the bottom surface portion 1, as shown in FIG. 35, the flat plate 15 may be provided with side walls 150 that vertically rise on each side forming its outer peripheral edge. In the present embodiment, side walls 150 are integrally provided on each of the four sides of the flat plate 15 having a rectangular shape in plan view. The butting portions 151 of two adjacent side walls 150 are connected by, for example, welding, caulking material, water stop tape, or the like. The height of the side walls 150 is designed such that its upper end protrudes above the corrugated plate 16 disposed on the flat plate 15. The space for placing the stored item on the bottom panel 11 is surrounded by a plurality of side walls 150 over the entire circumference. According to this modification example, if a liquid such as an electrolytic solution leaks from the stored item (for example, a lithium-ion battery) placed on the bottom panel 11, the liquid can be stopped inside the plurality of side walls 150 by the plurality of side walls 150, and leakage to the outside can be suppressed. In this modification example, a drain bolt, for example, may be installed on the bottom panel 11.

[0102] Also, in the storage container 100 of the above embodiment, although a part (lower part) of the front panel 36 that can be removed from the front frame 35 is composed of a composite panel of a flat plate and a corrugated plate, it may be entirely composed of a composite panel of a flat plate and a corrugated plate.

[0103] Also, in the storage container 100 of the above embodiment, although the front panel 36 is removable from the front frame 35 in the front surface portion 3D, the panel may be removable from the frame in the other side surface portions 3A - 3C or the top surface portion 2.

[0104] Also, in the storage container 100 of the above embodiment, composite panels of a flat plate and a corrugated plate are used for all the panels of the bottom surface portion 1, the top surface portion 2, and the plurality of side surface portions 3A - 3D. However, it is sufficient if a composite panel of a flat plate and a corrugated plate is used for at least one of the panels of the bottom surface portion 1, the top surface portion 2, and the plurality of side surface portions 3A - 3D. For example, for the top surface portion 2 and the front surface portion 3D where the front panel 36 is removable from the front frame 35, the panel can be composed of a flat steel plate, and for the bottom surface portion 1 and the other side surface portions 3A - 3C, the panel can be composed of a composite panel of a flat plate and a corrugated plate.

[0105] Also, the storage container 100 of the above embodiment has side surface portions that are boxes in a rectangular shape in plan view, but the side surface portions may be boxes in a polygonal shape in plan view with three or five or more sides.

[0106] Also, the shape of the frames in the bottom surface portion 1, the top surface portion 2, and the plurality of side surface portions 3, and the method of connecting the bottom surface portion 1, the top surface portion 2, and the plurality of side surface portions 3 to form a box shape are not limited to the above embodiment, and various methods can be adopted.

Example

[0107] Hereinafter, the operation and effect of the storage container of the present disclosure will be described based on examples. Note that the storage container of the present disclosure is not limited to the following examples.

[0108] <Fire resistance and heat resistance> A test was conducted to evaluate the fire resistance and heat resistance when a lithium-ion battery is housed in a storage container and a fire breaks out in the vicinity. The lithium-ion batteries used in the test were "18650 3500 mA 3.7V" manufactured by KEEP POWER, and those in a fully charged state (100% charged) and those in a state considered to have the highest charge rate at the distribution stage (50% charged) were used.

[0109] The test was carried out in accordance with the "Report on the Study of Safety Measures for Hazardous Facilities Related to Lithium-Ion Batteries" (published by the Dangerous Goods Safety Division of the Fire and Disaster Management Agency, Ministry of Internal Affairs and Communications in December 2011). The steel plate used as the test specimen was placed horizontally, and the lithium-ion battery was fixed at a position about 1 cm above the steel plate. A gas burner was installed below the steel plate, and the length of the flame was adjusted to about 10 cm so that the tip of the flame hit the steel plate. In this way, with the steel plate used as the test specimen inserted between the flame and the lithium-ion battery, the lithium-ion battery was heated by the flame, and the temperature rise value of the lithium-ion battery was measured using a thermocouple logger (model number 34970A) manufactured by Keysight. The heating time of the lithium-ion battery was set to 20 minutes, and the temperature obtained by subtracting the surface temperature of the battery immediately before heating from the surface temperature of the battery after 20 minutes of heating was defined as the temperature rise value of the lithium-ion battery. Considering the differences among individual lithium-ion batteries, the number of test runs for one test specimen was set to 3 times.

[0110] The test specimen of Example 1 is a composite panel in which a corrugated steel plate with a thickness of 0.35 mm is joined to one side of a flat steel plate with a thickness of 0.35 mm. The test specimen of Example 2 is a composite panel in which a corrugated steel plate with a thickness of 0.4 mm is joined to one side of a flat steel plate with a thickness of 0.4 mm. The test specimen of Example 3 is a composite panel in which a corrugated steel plate with a thickness of 0.5 mm is joined to one side of a flat steel plate with a thickness of 0.5 mm. The test specimen of the comparative example is a flat steel plate with a thickness of 1.6 mm.

[0111] For the test articles of Examples 1 to 3, a flat plate on the inner space side of the storage container was directed toward the lithium-ion battery side, and a flame was applied to the corrugated plate side on the outer side of the storage container. For the test articles of Examples 1 to 3, the tests were conducted separately when the tip of the flame hit the concave (valley) of the corrugated plate and when it hit the convex (peak) of the corrugated plate. Table 1 shows the test results for the lithium-ion battery in a fully charged state, and Table 2 shows the test results for the lithium-ion battery in a 50% charged state.

[0112]

Table 1

[0113]

Table 2

[0114] According to the test results in Table 1 and Table 2, it was confirmed that the composite panel combining a steel flat plate with a thickness of 0.35 mm or more and a steel flat plate with a thickness of 0.35 mm or more has performance equivalent to or better than that of a flat steel plate with a thickness of 1.6 mm in terms of fire resistance and heat resistance. From this, it can be seen that the composite panel of the flat plate and the corrugated plate can reduce the total thickness of the panel (the sum of the thickness of the flat plate and the thickness of the corrugated plate) compared to a steel plate having equivalent fire resistance and heat resistance.

[0115] <Fire resistance> A test was conducted to evaluate the fire resistance when the lithium-ion battery catches fire when the lithium-ion battery is stored in the storage container. The test was carried out in accordance with "Requirements for Specific Fire Protection Equipment (Article 112, Paragraph 1, of the Ordinance for Enforcement of the Building Standards Act): When heat from an ordinary fire is applied, no flame shall be emitted from the surface other than the heated surface within one hour after the start of heating."

[0116] The steel plate to be tested was installed vertically, and a flame was applied to the center of one surface of the steel plate from the side of the steel plate using a gas burner to heat the steel plate. After the start of heating, the temperature of the steel plate was measured at 1-minute intervals. The heating time of the steel plate was set to 60 minutes. The temperature of the steel plate was measured using a temperature logger (model number TDS-530) manufactured by Tokyo Measuring Instrument Laboratory Co., Ltd. The temperature of the steel plate was measured on each of the heated surface and the non-heated surface of the steel plate. For the heated surface, the temperature was measured at a position 10 cm away from the steel plate, and for the non-heated surface, the temperature was measured at positions 10 mm and 5 cm away from the center of the steel plate.

[0117] The test specimen of Example 1 is a composite panel in which a corrugated steel plate with a thickness of 0.35 mm is joined to one surface of a flat steel plate with a thickness of 0.35 mm. The test specimen of Example 2 is a composite panel in which a corrugated steel plate with a thickness of 0.4 mm is joined to one surface of a flat steel plate with a thickness of 0.4 mm. The test specimen of Example 3 is a composite panel in which a corrugated steel plate with a thickness of 0.5 mm is joined to one surface of a flat steel plate with a thickness of 0.5 mm. The test specimen of the comparative example is a flat steel plate with a thickness of 1.6 mm.

[0118] For the test specimens of Examples 1 to 3, the flat plate on the inner space side of the storage container was oriented toward the gas burner side, and the test was conducted by applying a flame to the flat plate side. In addition, for the test specimens of Examples 1 and 3, a test was also conducted by orienting the corrugated steel plate toward the gas burner side and applying a flame to the corrugated steel plate side. The test results are shown in Table 3.

[0119]

Table 3

[0120] According to the test results in Table 3, it was confirmed that the composite panel combining a flat steel plate with a thickness of 0.35 mm or more and a flat steel plate with a thickness of 0.35 mm or more has performance equivalent to or better than that of a steel plate with a thickness of 1.6 mm in terms of fire resistance.

[0121] Further, when the state of the unheated surface was visually observed after heating the steel plate, no significant shape change, damage such as cracks or fractures through which the flame passed was found in any of the test pieces of Comparative Example 1 and Examples 1 to 3. Therefore, since the test pieces of Examples 1 to 3 did not emit flames to the unheated surface side during heating, from this point as well, it was confirmed that the composite panel combining a steel flat plate with a thickness of 0.35 mm or more and a steel flat plate with a thickness of 0.35 mm or more had performance equivalent to or better than that of a 1.6-mm-thick steel plate in terms of fire resistance. Thus, it can be seen that the composite panel of the flat plate and the corrugated plate can reduce the total thickness of the panel (the sum of the thickness of the flat plate and the thickness of the corrugated plate) compared to a steel plate having equivalent fire resistance.

[0122] Note that the thicknesses of the flat plate and the corrugated plate in the above-described examples, 0.35 mm, 0.4 mm, and 0.5 mm, are merely examples. When the thickness of the flat plate and the thickness of the corrugated plate are less than 0.35 mm, it does not necessarily mean that they do not have fire resistance, heat resistance, and fireproof performance equivalent to or better than those of a 1.6-mm-thick steel plate, and the ranges less than 0.35 mm are not excluded for the thicknesses of the flat plate and the corrugated plate having fire resistance, heat resistance, and fireproof performance equivalent to or better than those of a 1.6-mm-thick steel plate.

Explanation of Signs

[0123] 100 Storage container 1 Bottom surface part 10 Bottom surface frame 11 Bottom surface panel 15 Flat plate 16 Corrugated plate 2 Top surface part 20 Top surface frame 21 Top surface panel 23 Flat plate 24 Corrugated plate 3A - 3D Side surface part 30 Side surface frames on both sides and the rear side 31 Side surface panels on both sides and the rear side 33 Flat plate 34 Corrugated plate 35 Side surface frame on the front side 36 Side surface panel on the front side

Claims

1. A storage container comprising a bottom surface portion and a top surface portion that are arranged opposite to each other, and a plurality of side surface portions that are erected along a plurality of sides of the bottom surface portion and the top surface portion between the bottom surface portion and the top surface portion. At least one of the bottom surface portion, the top surface portion, and the plurality of side surface portions includes a composite panel in which a steel flat plate and a steel corrugated plate are joined.

2. The bottom surface portion, the top surface portion, and the plurality of side surface portions include a frame-shaped frame and a panel fitted into the frame. The storage container according to claim 1, wherein the frame includes a support surface on which outer peripheral edge portions of the fitted panel are overlapped.

3. The storage container according to claim 1, wherein two adjacent side surface portions of the plurality of side surface portions are connected by fitting a convex portion formed at a lateral end of one side surface portion into a concave groove formed at a lateral end of the other side surface portion.

4. The storage container according to claim 1, wherein one of the top surface portion and the plurality of side surface portions is such that the panel is removable from the frame to form an entrance / exit for the stored item.

5. The storage container according to any one of claims 1 to 4, in which a lithium-ion battery is stored.

Images