Box for power storage element, testing device, and evaluation method

Abstract

This box for a power storage element is disposed inside a thermostatic tank in which performance testing of a power storage element is carried out. The box for the power storage element comprises a box body which houses the power storage element, and electrical wiring which extends inside the box body and which is electrically connected to a tab of the power storage element. The box body contains an insulating and flame-retardant material.

Description

Box for storage element, test device, and evaluation method

[0001] The present invention relates to a box for an electric storage element, a test device, and an evaluation method.

[0002] For example, as proposed in Patent Document 1, an energy storage element formed by stacking a positive electrode and a negative electrode is known as a secondary battery. Energy storage elements are widely used in various applications such as vehicle-mounted applications and stationary residential applications.

[0003] The performance of an energy storage device is evaluated by a performance test conducted before actual use. In one example of the performance test, the energy storage device to be evaluated is repeatedly charged and discharged over a long period of time (e.g., several months). The performance test is conducted in a thermostatic chamber, and the performance is evaluated under environmental conditions that simulate the environment in which the energy storage device will be used.

[0004] A plurality of energy storage elements are placed in the thermostatic chamber to be evaluated for performance under the same conditions. By evaluating the performance of a plurality of energy storage elements, the reliability of the evaluation results can be improved.

[0005] A malfunction can occur inside the thermostatic chamber during performance testing of energy storage elements. For example, a short circuit can occur between two energy storage elements. In performance testing under harsh conditions, it is even conceivable that one of the energy storage elements may burn. Furthermore, a malfunction occurring inside the thermostatic chamber can affect other energy storage elements being tested that are unrelated to the cause of the malfunction. In other words, a single malfunction can prevent the performance of multiple energy storage elements placed inside the thermostatic chamber from being properly evaluated. Furthermore, it may become necessary to re-perform performance tests that require a long period of time on a large number of energy storage elements. Because a long-term performance test must be re-performed, evaluation results are obtained significantly later than originally planned.

[0006] Patent Document 1: JP2016-29617A

[0007] The present invention has been made in consideration of the above points, and an object of the present invention is to accurately and stably evaluate the performance of a plurality of energy storage elements by testing them in a thermostatic chamber.

[0008] A first storage element box according to one embodiment of the present invention is a storage element box placed in a constant temperature bath where performance tests of the storage elements are conducted, and comprises: a box body containing an insulating and flame-retardant material and housing the storage elements; and electrical wiring extending within the box body and electrically connecting to the storage elements.

[0009] A second storage element box according to one embodiment of the present invention is a storage element box placed in a constant temperature bath where performance tests of the storage elements are conducted, and comprises a box body including a wall portion that defines a storage chamber that houses the storage elements, and electrical wiring that extends within the box body and electrically connects to the storage elements, and a through hole is provided in the wall portion.

[0010] A first testing apparatus according to one embodiment of the present invention is a testing apparatus for conducting performance tests on energy storage elements, and comprises: a constant temperature bath; and a plurality of energy storage element boxes arranged within the constant temperature bath, each of which is capable of accommodating one of the energy storage elements.

[0011] A second test apparatus according to one embodiment of the present invention is a test apparatus for conducting performance tests on energy storage elements, and comprises: a constant temperature chamber; and a plurality of energy storage element boxes placed in the constant temperature chamber, each of which is a first or second energy storage element box according to one embodiment of the present invention.

[0012] A first evaluation method according to one embodiment of the present invention is a method for evaluating the performance of a storage element, and includes the steps of: placing a plurality of storage element boxes, each containing the storage element, in a constant temperature bath; and conducting a test of the storage element in the constant temperature bath.

[0013] A second evaluation method according to one embodiment of the present invention is a method for evaluating the performance of a storage element, and includes the steps of: placing a plurality of storage element boxes, each containing the storage element, in a constant temperature bath; and testing the storage elements in the constant temperature bath, wherein each storage element box is the first or second storage element box according to one embodiment of the present invention.

[0014] According to the present invention, the performance of a plurality of energy storage elements can be evaluated accurately and stably by testing in a thermostatic chamber.

[0015] FIG. 1 is a diagram for explaining one embodiment and is a front view showing an example of a testing apparatus including a thermostatic chamber and a box for energy storage elements. FIG. 2 is a perspective view showing the box for energy storage elements shown in FIG. 1. FIG. 3 is a top view showing the box for energy storage elements shown in FIG. 2 together with energy storage elements, with the lid removed. FIG. 4 is a vertical cross-section showing the box for energy storage elements shown in FIG. 2 together with energy storage elements. FIG. 4 is a cross-section taken along line IV-IV in FIG. 3. FIG. 5 is a vertical cross-section showing the box for energy storage elements shown in FIG. 2 together with energy storage elements. FIG. 4 is a cross-section taken along line V-V in FIG. 3. FIG. 6 is a top view showing the box for energy storage elements shown in FIG. 2 with the lid removed. FIG. 7 is a perspective view showing an example of energy storage elements accommodated in the box for energy storage elements shown in FIG. 2.

[0016] One embodiment of the present disclosure relates to the following <1> to <19>.

[0017] <1> A box for an energy storage element that is placed in a thermostatic chamber in which a performance test of the energy storage element is conducted, the box comprising: a box body that contains an insulating and flame-retardant material and that houses the energy storage element; and electrical wiring that extends within the box body and electrically connects to the energy storage element.

[0018] <2> The box for an energy storage element according to <1>, wherein the box body includes a wall portion that defines a chamber that accommodates the energy storage element, and the wall portion has insulating properties and flame retardancy.

[0019] <3> The box for an energy storage element according to <1> or <2>, wherein the box body includes a wall portion that defines a chamber that accommodates the energy storage element, and the wall portion has a thickness of 0.5 mm or more.

[0020] <4> The box for storage devices according to any one of <1> to <3>, wherein the material has a glass transition temperature of 100°C or higher.

[0021] <5> The box for an energy storage element according to any one of <1> to <4>, wherein the box body includes a wall portion that defines a chamber that accommodates the energy storage element, and the wall portion is provided with a through hole.

[0022] <6> A box for an energy storage element that is placed in a thermostatic chamber in which a performance test of the energy storage element is conducted, the box comprising: a box main body including a wall portion that defines a storage chamber that stores the energy storage element; and electrical wiring that extends within the box main body and is electrically connected to the energy storage element, wherein a through hole is provided in the wall portion.

[0023] <7> The box for storage devices according to <5> or <6>, wherein the through holes have an opening ratio of 10% or more.

[0024] <8> The box for storage devices according to any one of <5> to <7>, wherein the through holes include two or more through holes positioned apart from each other.

[0025] <9> The box for storage elements according to any one of <5> to <8>, wherein the wall portion includes two plate portions facing each other with the storage chamber therebetween, and the through hole includes a through hole provided in each of the two plate portions.

[0026] <10> The box for storage elements according to any one of <5> to <9>, wherein the wall portion includes two plate portions facing each other with the storage chamber therebetween, and the through holes include through holes provided in each of the two plate portions and facing each other.

[0027] <11> The box for storage elements according to any one of <5> to <10>, wherein the wall portion includes a plurality of plate portions facing each other with the storage chamber interposed therebetween, and the through hole includes a through hole provided in each of the plurality of plate portions.

[0028] <12> The box for storage elements according to any one of <5> to <11>, wherein the storage elements housed in the box body can be observed from outside the box body through the through hole.

[0029] <13> The box for an energy storage element according to any one of <1> to <12>, wherein the energy storage element includes an electrode body, an exterior material that houses the electrode body, and a tab that is electrically connected to the electrode body and extends from the exterior material, and the electrical wiring includes two electrical wirings that are connected to different tabs of the energy storage element.

[0030] <14> The box for an energy storage element according to any one of <1> to <13>, wherein the energy storage element includes an electrode body, an exterior material that houses the electrode body, and a tab that is electrically connected to the electrode body and extends from the exterior material, and further includes a terminal block to which the electrical wiring and the tab of the energy storage element are fixed, and the terminal block is attached to the box body.

[0031] <15> The box for an energy storage element according to any one of <1> to <14>, wherein the energy storage element includes an electrode body and an exterior material that houses the electrode body, and a maximum value of a distance between the exterior material of the energy storage element housed in the box main body and the box main body is 10% or less of a length of a long side of the exterior material.

[0032] <16> A test apparatus for conducting a performance test of an electric storage element, the test apparatus comprising: a thermostatic chamber; and a plurality of boxes for electric storage elements arranged in the thermostatic chamber, each box for electric storage elements being capable of accommodating one of the electric storage elements.

[0033] <17> A test apparatus for conducting a performance test of an electric storage element, the test apparatus comprising: a thermostatic chamber; and a plurality of boxes for electric storage elements arranged in the thermostatic chamber, each of which is a box for electric storage elements according to any one of <1> to <15>.

[0034] <18> A method for evaluating the performance of an energy storage element, the method comprising: a step of placing a plurality of energy storage element boxes, each of which houses the energy storage element, in a thermostatic chamber; and a step of conducting a test of the energy storage elements in the thermostatic chamber.

[0035] <19> A method for evaluating the performance of an electric storage element, the method comprising: a step of placing a plurality of boxes for electric storage elements, each of which houses the electric storage element, in a thermostatic chamber; and a step of testing the electric storage elements in the thermostatic chamber, wherein each box for electric storage elements is a box for electric storage elements according to any one of <1> to <15>.

[0036] An embodiment of the present disclosure will be described below with reference to the drawings. In the drawings accompanying this specification, the scale and aspect ratios have been appropriately changed and exaggerated from those of the actual objects for ease of understanding. Configurations shown in some drawings may be omitted in other drawings. The scale and aspect ratios may differ between the drawings.

[0037] In this specification, terms that specify shapes, geometric conditions, and their degrees, such as "parallel," "orthogonal," and "identical," as well as values ​​of lengths and angles, are not limited to their strict meanings, but are interpreted to include a range within which similar functions can be expected.

[0038] In order to clarify the relationship between directions between drawings, several drawings use arrows with common symbols to indicate a common first direction D1, second direction D2, and third direction D3. The tip of the arrow is the first side of each direction. The side opposite the tip of the arrow is the second side of each direction. An arrow pointing away from the paper surface in a direction perpendicular to the paper surface of the drawing is indicated by a symbol with an x ​​in a circle, as shown in FIG. 1, for example. An arrow pointing away from the paper surface in a direction perpendicular to the paper surface of the drawing is indicated by a symbol with a dot in a circle, as shown in FIG. 3, for example.

[0039] In the illustrated example, the first direction D1 and the second direction D2 are parallel to the horizontal direction, the first direction D1 and the second direction D2 are perpendicular to each other, and the third direction D3 is parallel to the vertical direction.

[0040] In this specification, multiple upper limit candidate values ​​and multiple lower limit candidate values ​​for a numerical range may be described in separate sentences. In this description, the numerical range may be constructed by combining any one upper limit candidate value and any one lower limit candidate value. As an example, consider the description, "Parameter B may be A1 or more, A2 or more, or A3 or more. Parameter B may be A4 or less, A5 or less, or A6 or less." In this example, the numerical range of parameter B may be A1 or more and A4 or less, A1 or more and A5 or less, A1 or more and A6 or less, A2 or more and A4 or less, A2 or more and A5 or less, A2 or more and A6 or less, A3 or more and A4 or less, A3 or more and A5 or less, or A3 or more and A6 or less.

[0041] 1 to 7 are diagrams illustrating one embodiment. FIG. 1 is a front view showing one specific example of a test apparatus 5 in this embodiment. The test apparatus 5 includes a thermostatic chamber 10 and a plurality of energy storage element boxes 20. The energy storage element boxes 20 house energy storage elements 60. As shown in FIG. 1, a plurality of energy storage element boxes 20 can be placed in the thermostatic chamber 10 at the same time.

[0042] A storage element 60 is housed in each storage element box 20. The storage element 60 is a secondary battery. The storage element 60 may be the smallest unit of an element capable of storing electricity. In actual use, the storage element 60 may be electrically connected to other storage elements 60 directly or in parallel. The storage element 60 may also constitute a storage element module together with other storage elements 60. Various types of storage elements 60 may be employed. The storage element 60 may be, for example, a lithium-ion secondary battery.

[0043] FIG. 7 shows a specific example of an energy storage element 60 that can be housed in the energy storage element box 20. The energy storage element 60 shown in FIG. 3 has a flat shape. As shown in FIG. 3, the energy storage element 60 may include an electrode body 62, an exterior material 64, and a tab 66. The electrode body 62 may include a positive electrode plate and a negative electrode plate. The electrode body 62 may include a plurality of positive electrode plates and a plurality of negative electrode plates stacked alternately. The exterior material 64 houses the electrode body 62. The exterior material 64 forms a sealed space that houses the electrode body 62. The tab 66 is electrically connected to the electrode body 62 and extends to the outside of the exterior material 64. The tab 66 functions as a terminal of the energy storage element 60.

[0044] However, the energy storage element 60 shown in FIG. 7 is merely an example. The energy storage element 60 may have a configuration different from that shown in FIG. 7. In the example shown in FIG. 7, the energy storage element 60 includes a pair of tabs 66 protruding on both sides in the first direction D1, which is the longitudinal direction. However, this example is not limited thereto, and the energy storage element 60 may include a tab 66 extending in a direction other than the first direction D1. The energy storage element 60 may include a tab 66 protruding on only one side in either direction. Furthermore, the energy storage element 60 may not include a tab 66 protruding from the exterior material 64. In this example, the electrical wiring 22, which will be described later, may be connected to a terminal portion of the electrode body 62. The terminal portion may be a part of a positive electrode plate or a negative electrode plate included in the electrode body 62.

[0045] The performance of the energy storage element 60 is evaluated prior to actual use. The test device 5 is a device for conducting tests to evaluate the performance of the energy storage element 60. As an example, the energy storage element 60 is evaluated to see whether it can withstand a test in which charging and discharging are repeated over a long period of time. During the test, the thermostatic chamber 10 maintains the thermostatic chamber 12 containing the energy storage element box 20 at a test temperature. The test temperature may be the temperature of the environment in which the energy storage element 60 to be evaluated is used.

[0046] A plurality of energy storage element boxes 20 are placed in the thermostatic chamber 10, each containing an energy storage element 60. The test device 5 can simultaneously test the performance of the plurality of energy storage elements 60. In this embodiment, a performance test using one thermostatic chamber 10 is performed to enable the performance of the plurality of energy storage elements 60 to be evaluated accurately and stably.

[0047] The thermostatic bath 10 and the storage element box 20 will be described below in order.

[0048] The thermostatic bath 10 has a thermostatic chamber 12 that houses the energy storage element box 20. The thermostatic bath 10 can maintain the temperature of the thermostatic chamber 12. The thermostatic bath 10 can maintain the temperature of the thermostatic chamber 12 at a temperature other than room temperature. The thermostatic bath 10 may be able to set the temperature of the thermostatic chamber 12 to any temperature within a predetermined temperature range. The predetermined temperature is not particularly limited and may be selected depending on the application of the energy storage element 60 to be evaluated. As an example, the predetermined temperature may be −70° C. or higher and 80° C. or lower. If the internal temperature of the thermostatic bath 10 is changeable, performance tests under different temperature conditions can be performed using a single testing device 5.

[0049] There is no limit to the number of energy storage element boxes 20 that can be placed simultaneously in the temperature-controlled chamber 12 of the temperature-controlled bath 10. In the example shown in Fig. 1 , 12 energy storage element boxes 20 can be placed in the temperature-controlled bath 10.

[0050] The configuration of the thermostatic bath 10 is not particularly limited. The thermostatic bath 10 may be any of various known ovens. In the example shown in Fig. 1, the thermostatic bath 10 includes a partition wall 14 that partitions the thermostatic chamber 12. The partition wall 14 may include a door. The thermostatic chamber 12 may be openable by the door.

[0051] As shown in FIG. 1 , the thermostatic bath 10 may include shelves 16 arranged in the thermostatic chamber 12. In the example shown in FIG. 1 , the shelves 16 are held by the partition wall 14. The shelves 16 extend horizontally in a direction perpendicular to the third direction D3. Three shelves 16 are arranged at intervals in the third direction D3. By using the shelves 16, the number of energy storage element boxes 20 that can be arranged in the thermostatic chamber 12 can be increased.

[0052] As shown in FIG. 1 , the thermostatic chamber 10 may include a removable mounting base 18. The mounting base 18 may be slidably provided on a shelf 16. The mounting base 18 may be movable only in a first direction D1 relative to the partition wall 14 and the shelf 16. In the illustrated example, four mounting bases 18 are arranged on one shelf 16. The four mounting bases 18 are arranged in a second direction D2. One energy storage element box 20 can be mounted on one mounting base 18. Unlike the illustrated example, two energy storage element boxes 20 may be mounted on one mounting base 18. By making the mounting base 18 removable from within the thermostatic chamber 12, it is possible to easily place the energy storage element boxes 20 in and remove them from the thermostatic chamber 12.

[0053] The energy storage element box 20 includes a box body 30 and electrical wiring 22. The box body 30 has an accommodation chamber 30a. The box body 30 is capable of accommodating an energy storage element 60 in the accommodation chamber 30a. The electrical wiring 22 extends within the accommodation chamber 30a. The electrical wiring 22 is electrically connected to a tab 66 of the energy storage element 60. The electrical wiring 22 may be in direct contact with the tab 66 or may be electrically connected to the tab 66 via a conductive intermediary.

[0054] The box body 30 may include a material that is insulating and flame-retardant. A "material that has insulating properties" is a material having a volume resistivity of 1.0×10 ６ It means that the electrical resistance is greater than Ω cm. An example of an insulating material is resin. A "flame-retardant" material means a material that is rated at "V-2" or higher in the UL94 standard for flame retardancy established and approved by Underwriters Laboratories Inc. in the United States. There are no particular limitations on the insulating and flame-retardant materials.

[0055] An example of a material having insulating and flame-retardant properties is Bakelite (registered trademark). Bakelite is a cured product of a thermosetting resin composition. Bakelite is a phenolic resin obtained by curing phenol and formaldehyde. Bakelite has excellent insulating properties and excellent flame-retardant properties.

[0056] Other insulating and flame-retardant materials include thermoplastic resins such as liquid crystal polymers, polyether ether ketone, polyphenylene sulfide, polyphenylene ether, polyphenylene oxide, polyetherimide, polyethersulfone, polyethylene naphthalate, polyethylene terephthalate, and thermoplastic polyimides, or polymer alloys thereof, as well as polyimides, heat-resistant epoxy resins, cyanate resins such as bismaleimide triazine, thermosetting resins such as thermosetting modified polyphenylene ethers and phenolic resins. A substrate such as paper, cotton cloth, or glass cloth impregnated with resin varnish as a reinforcing agent may also be used as the insulating and flame-retardant wall portion.

[0057] When the material is a resin, a lower limit may be set for the glass transition temperature Tg (°C) of the material. By setting a lower limit for the glass transition temperature Tg (°C) of the material, it is possible to prevent a malfunction of an energy storage element 60 occurring in the temperature-controlled chamber 12 of the thermostatic bath 10 from affecting other energy storage elements 60, as will be described later. The glass transition temperature Tg of the material may be 100°C or higher, 110°C or higher, 120°C or higher, or 140°C or higher. No upper limit is particularly set for the glass transition temperature Tg of the material. The glass transition temperature Tg of the material may be 200°C or lower.

[0058] The box body 30 may include a wall portion 35 that partitions the storage chamber 30a. The wall portion 35 may include a material that is insulating and flame-retardant. The wall portion 35 may be made of a material that is insulating and flame-retardant.

[0059] A lower limit may be set for the thickness (mm) of the wall portion 35. By setting a lower limit for the thickness (mm) of the wall portion 35, it is possible to prevent a defect in one of the energy storage elements 60 occurring in the temperature-controlled chamber 12 of the thermostatic bath 10 from affecting other energy storage elements 60, as will be described later. The thickness of the wall portion 35 may be 0.5 mm or more, 1.0 mm or more, 2.0 mm or more, or 5.0 mm or more. No upper limit is particularly set for the thickness of the wall portion 35. The thickness of the wall portion 35 may be 20 mm or less, or 10 mm or less.

[0060] As shown in Figures 2 to 6, the box body 30 may have a rectangular parallelepiped shape. In the illustrated example, the wall portion 35 includes side plate portions 36, a bottom plate portion 37, and a top plate portion 38 as plate portions. One or more of the side plate portions 36, the bottom plate portion 37, and the top plate portion 38 may be simply referred to as a "plate portion." The bottom plate portion 37 and the top plate portion 38 face each other in the first direction D1. The side plate portion 36 connects the bottom plate portion 37 and the top plate portion 38. The side plate portion 36 is cylindrical with an axial direction along the third direction D3. The side plate portion 36 is rectangular cylindrical. The side plate portion 36 includes four plate portions.

[0061] As shown in FIG. 2 , the box body 30 may include a storage box portion 31 and a lid portion 32. In the example shown in FIG. 2 , the storage box portion 31 includes a side plate portion 36 and a bottom plate portion 37. The storage box portion 31 is open to a first side in the first direction D1. The lid portion 32 includes a top plate portion 38. The lid portion 32 closes the opening of the storage box portion 31. The lid portion 32 may be maintained in a state in which the opening of the storage box portion 31 is closed by a fixing device (not shown). The lid portion 32 may be swingably connected to the storage box portion 31 by a hinge (not shown).

[0062] An upper limit may be set on the ratio of the maximum distance between the box body 30 and the exterior packaging material 64 of the energy storage elements 60 housed in the box body 30 to the length of the long side of the exterior packaging material. By setting an upper limit on this ratio, the performance of multiple energy storage elements 60 can be evaluated more accurately and efficiently through a performance test using one thermostatic chamber 10, as will be described later. The maximum distance between the box body 30 and the exterior packaging material 64 of the energy storage elements 60 housed in the box body 30 may be 10% or less of the length of the long side of the exterior packaging material, 8% or less, or 5% or less. No lower limit is particularly set on this ratio. This ratio may be 0% or more, or may be greater than 0%.

[0063] Here, "distance" refers to the shortest length from each position on the energy storage element 60 to the inner surface of the box body 30. Even when a through hole 40 (described later) is formed, the "distance" is determined on the assumption that the inner surface is blocked. "Maximum distance" refers to the maximum distance determined for any position on the energy storage element 60 housed in the box body 30.

[0064] 2, a through-hole 40 may be provided in the wall portion 35. The through-hole 40 is a hole that penetrates the wall portion 35. The through-hole 40 connects the outside of the wall portion 35 with the inside of the wall portion 35. Gas at a predetermined temperature in the temperature-controlled chamber 12 can enter the storage chamber 30a through the through-hole 40.

[0065] A lower limit may be set for the opening ratio of the through holes 40. The opening ratio is the ratio of the opening area of ​​the through holes 40 to the surface area of ​​the box body 30 in the case where the through holes 40 are not formed. The opening ratio is expressed in "%".

[0066] Setting a lower limit to the aperture ratio of the through holes 40 makes it easier for gas to move through the through holes 40, thereby promoting heat exchange between the temperature-controlled chamber 12 and the storage chamber 30a. That is, the temperature of the storage chamber 30a can be quickly brought closer to the temperature of the temperature-controlled chamber 12. Furthermore, setting a lower limit to the aperture ratio of the through holes 40 makes it easier to observe the energy storage elements 60 stored in the energy storage element box 20 through the through holes 40. The aperture ratio of the through holes 40 may be 10% or more, 15% or more, 20% or more, 25% or more, or 30% or more.

[0067] There is no particular upper limit set for the opening rate of the through holes 40. From the viewpoint of ensuring the rigidity of the box body 30, the opening rate of the through holes 40 may be 70% or less, 60% or less, or 50% or less.

[0068] The shape of the through holes 40 is not particularly limited. In the illustrated example, the opening of the through holes 40 has a circular or elliptical shape. The opening of the through holes 40 may have a triangular, rectangular, or pentagonal shape. The shapes and sizes of the through holes 40 provided in the wall portion 35 may be the same as or different from each other.

[0069] Two or more through holes 40 positioned apart from each other may be provided in the wall portion 35. As shown in Figures 2 to 6, multiple through holes 40 may be provided in the wall portion 35.

[0070] The wall portion 35 may include two plate portions facing each other with the storage chamber 30a in between, and each of the two plate portions may be provided with a through hole 40. As shown in Fig. 3, the side plate portion 36 includes four plate portions, and two plate portions facing each other in the first direction D1 may be provided with a through hole 40. As shown in Fig. 3, the side plate portion 36 includes four plate portions, and two plate portions facing each other in the second direction D2 may be provided with a through hole 40. As shown in Figs. 4 and 5, the bottom plate portion 37 and the top plate portion 38 facing each other in the third direction D3 may be provided with a through hole 40.

[0071] The wall portion 35 may include two plate portions facing each other with the storage chamber 30a in between, and each of the two plate portions may be provided with a through hole 40 facing directly opposite each other. As shown in Fig. 3, the side plate portion 36 may include four plate portions, and two plate portions facing each other in the first direction D1 may be provided with a through hole 40 facing directly opposite each other. As shown in Fig. 3, the side plate portion 36 may include four plate portions, and two plate portions facing each other in the second direction D2 may be provided with a through hole 40 facing directly opposite each other. As shown in Figs. 4 and 5, the bottom plate portion 37 and the top plate portion 38 facing each other in the third direction D3 may be provided with a through hole 40 facing directly opposite each other.

[0072] The wall portion 35 may include a plurality of plate portions 36, 37, 38 that face each other across the storage chamber 30a, and each of the plurality of plate portions 36, 37, 38 may be provided with a through hole 40. That is, the wall portion 35 may include a plurality of plate portions 36, 37, 38 that face each other across the storage chamber 30a, and each of the plate portions 36, 37, 38 included in the wall portion 35 may be provided with a through hole 40. In the example shown in Figures 2 to 6, all of the plate portions 36, 37, 38 are provided with a through hole 40.

[0073] As shown in Figures 3 and 6, the energy storage element box 20 includes electrical wiring 22 provided in the accommodation chamber 30a. The electrical wiring 22 is electrically connected to the energy storage element 60. In the illustrated example, the electrical wiring 22 is electrically connected to a tab 66 of the energy storage element 60. The electrical wiring 22 may be in direct contact with the tab 66, or may be electrically connected to the tab 66 via a conductive intermediary. The electrical wiring 22 is not shown in figures other than Figures 3 and 6.

[0074] 3 and 6, the storage element box 20 may include two or more electrical wirings 22. In the illustrated example, the storage element box 20 includes, as the electrical wirings 22, a first main electrical wiring 23A, a second main electrical wiring 23B, and a thermocouple 24.

[0075] The first main electrical wiring 23A and the second main electrical wiring 23B are electrically connected to different portions of the energy storage element 60, for example, different tabs 66. In the illustrated example, the first main electrical wiring 23A is electrically connected to the tab 66 located on a first side in the first direction D1. The second main electrical wiring 23B is electrically connected to the tab 66 located on a second side in the first direction D1.

[0076] In the illustrated example, the first main electrical wiring 23A and the second main electrical wiring 23B have crimp terminals 25 fixed to their tips. Unlike the illustrated example, the first main electrical wiring 23A and the second main electrical wiring 23B may have connectors other than the crimp terminals 25 fixed to their tips. The first main electrical wiring 23A and the second main electrical wiring 23B may have conductive clips, such as alligator clips, fixed to their tips. Furthermore, the method for electrically connecting the first main electrical wiring 23A and the second main electrical wiring 23B to the energy storage element 60 is not particularly limited. The first main electrical wiring 23A and the second main electrical wiring 23B may be fixed in direct contact with the energy storage element 60 by resistance welding or the like, thereby ensuring electrical connection between the first main electrical wiring 23A and the second main electrical wiring 23B and the energy storage element 60. The electrical connection between the first main electrical wiring 23A and the second main electrical wiring 23B and the energy storage element 60 may also be ensured via a conductive member, such as a metal.

[0077] As shown in FIG. 2 , the tip of the thermocouple 24 may be kept in contact with the energy storage element 60 by a fixing device 24a such as tape. According to this example, the thermocouple 24 can be used to measure the temperature of the energy storage element 60. Unlike the illustrated example, the thermocouple 24 may measure the ambient temperature of the accommodation chamber 30a. The thermocouple 24 may measure the temperature of the box body 30. In the illustrated example, the energy storage element box 20 includes one thermocouple 24. The energy storage element box 20 may include two or more thermocouples 24, allowing measurements to be made at multiple locations on the energy storage element 60.

[0078] 3 and 6 , the energy storage element box 20 may include an electrical connector 28. The electrical connector 28 is electrically connected to the base ends of the electrical wiring 22. The base ends of the first main electrical wiring 23A and the second main electrical wiring 23B are each attached to the electrical connector 28. The base end of the thermocouple 24 is also attached to the electrical connector 28.

[0079] 2, the electrical connector 28 is also electrically connected to the electrical wiring 19 of the thermostatic chamber 10. Power is transmitted to and received from the power storage element 60 using the electrical wiring 19, the first main electrical wiring 23A, and the second main electrical wiring 23B. The measurement results of the thermocouple 24 are transmitted to an external controller using the electrical wiring 19, and the temperature is calculated.

[0080] As clearly shown in Figures 4 to 6, the energy storage element box 20 may include a terminal block 26. The terminal block 26 is provided inside the box body 30, i.e., in the accommodation chamber 30a. The terminal block 26 may be fixed to the box body 30. The terminal block 26 may be movably attached to the box body 30. The terminal block 26 may be attached to the box body 30 so as to be movable relative to the box body 30 in a first direction D1 that is parallel to the longitudinal direction of the energy storage element 60.

[0081] As described above, various changes are possible to the position of the tab 66 of the energy storage element 60. The terminal block 26 may be fixed to the box body 30 at a position facing the tab 66 of the energy storage element 60.

[0082] The ends of the first main electrical wiring 23A and the second main electrical wiring 23B may be fixed to the terminal block 26 using a fixing device 27. The tab 66 of the energy storage element 60 may be fixed to the terminal block 26 using the fixing device 27. In the example shown in FIGS. 4 to 6 , the fixing device 27 is a screw or a bolt. A hole through which the fixing device 27 passes is formed in the tab 66. The fixing device 27 can be fixed to the terminal block 26 by passing through the tab 66 and the crimp terminal 25. This allows the tab 66 and the crimp terminal 25 to be maintained in an electrically connected state. After the test is completed, the fixing device 27 can be removed from the terminal block 26, allowing the energy storage element 60 to be removed from the box body 30.

[0083] As described above, conductive clips (e.g., alligator clips) may be provided at the ends of the first main electrical wiring 23A and the second main electrical wiring 23B instead of the crimp terminals 25. According to this example, the tabs 66 may be electrically connected to the first main electrical wiring 23A and the second main electrical wiring 23B by the clips clamping the tabs 66 or by the clips clamping the conductive fasteners 27. As another example, the crimp terminals 25 may not be provided at the ends of the first main electrical wiring 23A and the second main electrical wiring 23B, and the ends of the first main electrical wiring 23A and the second main electrical wiring 23B may be directly fixed to the terminal block 26 by the fasteners 27.

[0084] As shown in FIGS. 4 to 6 , the energy storage element box 20 may include a support base 42 that supports the energy storage element 60 in the accommodation chamber 30a. As shown in FIG. 4 , by placing the energy storage element box 20 on the support base 42, it is possible to prevent the energy storage element 60 from bending when the tab 66 on the terminal block 26 is in place. This allows the energy storage element 60 to be placed in the accommodation chamber 30a in a position similar to that in which the energy storage element 60 is actually used, thereby improving the reliability of performance tests. In addition, it is possible to separate the energy storage element 60 from the wall portion 35 (e.g., the bottom plate portion 37), thereby making the temperature of the energy storage element 60 uniform.

[0085] As shown in Figures 4 to 6, the energy storage element box 20 may include a plurality of support bases 42. In the example shown in Figures 4 to 6, two support bases 42 are arranged in the second direction D2. Each support base 42 is elongated and has a longitudinal direction in the first direction D1.

[0086] As shown in FIGS. 4 to 6 , the support base 42 may include a table 43 and a base 44. The table 43 is in planar contact with the energy storage element 60. The table 43 supports the energy storage element 60 from the second side in the third direction D3. The base 44 supports the table 43 at a distance from the bottom plate portion 37. The table 43 may be fixed to the bottom plate portion 37 via the base 44. In the illustrated example, one table 43 extending in the first direction D1 is supported by a plurality of (e.g., three) bases 44 arranged in the first direction D1.

[0087] 6, a through hole 43a may be provided in the table 43. The through hole 43a may be directly opposite the through hole 40 provided in the bottom plate portion 37 in the first direction D1.

[0088] The operation of the test device 5 and the storage element box 20 configured as above will now be described.

[0089] The test device 5 is used for testing to evaluate the performance of the energy storage elements 60. An evaluation method for evaluating the performance of the energy storage elements includes a step of placing a plurality of energy storage element boxes 20, each accommodating an energy storage element 60, in a thermostatic chamber 10, and a step of testing the energy storage elements 60 in the thermostatic chamber 10.

[0090] First, the energy storage element 60 to be evaluated is accommodated in the box body 30 of the energy storage element box 20. In the energy storage element box 20, the electrical wiring 22 is electrically connected to the tab 66 of the energy storage element 60 located in the accommodation chamber 30a.

[0091] In the illustrated example, the energy storage element 60 is placed in the storage chamber 30a of the box body 30 so that the longitudinal direction of the exterior material 64 is parallel to the first direction D1. At this time, the lid portion 32 of the box body 30 leaves the upper opening of the storage box portion 31 open.

[0092] One tab 66 of the energy storage element 60 is placed on one terminal block 26. The tip end of the first main electrical wiring 23A is also placed on one terminal block 26 together with the one tab 66. Using a fixture 27, the crimp terminal 25 fixed to the one tab 66 and the tip end of the first main electrical wiring 23A is fixed to the terminal block 26. This keeps the one tab 66 and the first main electrical wiring 23A electrically connected.

[0093] The other tab 66 of the energy storage element 60 is placed on the other terminal block 26. The tip end of the second main electrical wiring 23B is also placed on the other terminal block 26 together with the other tab 66. The crimp terminal 25 fixed to the other tab 66 and the tip end of the second main electrical wiring 23B is fixed to the terminal block 26 using a fixing device 27. This keeps the other tab 66 and the second main electrical wiring 23B electrically connected.

[0094] In the illustrated example, the tip of the thermocouple 24 is placed and fixed at the position where the temperature is to be measured using a fixture 24a.

[0095] This completes the placement of the energy storage element 60 in the accommodation chamber 30a and the installation of the electrical wiring 22 in the accommodation chamber 30a. Thereafter, the opening of the box body 30 is closed by the lid 32. The lid 32 is fixed to the box body 30 with the opening of the box body 30 closed.

[0096] The above-described operations are performed on the energy storage element boxes 20 that have been removed from the temperature-controlled chamber 12 of the temperature-controlled bath 10. This allows for easy and stable preparation for testing related to the energy storage elements 60 and the electrical wiring 22. This effectively prevents unintended physical damage to the energy storage elements 60 and problems such as short circuits within one energy storage element box 20.

[0097] The storage element boxes 20 housing the storage elements 60 are then placed in the temperature-controlled chamber 12. A plurality of storage element boxes 20 are placed in the temperature-controlled chamber 12. The box body 30 of each storage element box 20 houses a storage element 60. The electrical connector 28 of the storage element box 20 placed in the temperature-controlled chamber 12 is electrically connected to the electrical wiring 19 of the temperature-controlled bath 10.

[0098] In the testing apparatus 5 shown in FIG. 1 , the energy storage element box 20 accommodating the energy storage elements 60 is placed on the mounting base 18 of the thermostatic chamber 10. When placing the energy storage element box 20, the mounting base 18 is pulled out from the shelf 16 inside the thermostatic chamber 12 toward the second side in the first direction D1. This makes it possible to easily place the energy storage element box 20 on the mounting base 18. Next, the mounting base 18 is slid toward the first side in the first direction D1 relative to the shelf 16 and the partition wall 14. This places the energy storage element box 20 at a predetermined position inside the storage chamber 30a.

[0099] The electrical wiring 19 (see FIG. 2 ) of the thermostatic bath 10 is electrically connected to the electrical connector 28 of each energy storage element box 20. This operation may be performed with the mounting base 18 pulled out from the shelf 16. This operation may also be performed with the mounting base 18 and the energy storage element boxes 20 placed in the accommodation chamber 30a. In the illustrated example, by moving the mounting base 18 toward the accommodation chamber 30a, the electrical connector of the thermostatic bath 10 may be inserted into the electrical connector 28 of the energy storage element box 20, automatically ensuring electrical connection.

[0100] This completes the process of placing a plurality of energy storage element boxes 20, each housing an energy storage element 60, in the thermostatic chamber 10. Next, a process of testing the energy storage elements 60 in the thermostatic chamber 10 is carried out.

[0101] After the electrical connection between the thermostatic chamber 10 and the energy storage element box 20 is secured, a performance test is conducted to evaluate the performance of the multiple energy storage elements 60 housed in the thermostatic chamber 12. A charge / discharge test is one example of the performance test. In the charge / discharge test, the energy storage elements to be evaluated are repeatedly charged and discharged over a long period of time (for example, several months). During the performance test, the thermostatic chamber 12 of the thermostatic chamber 10 is set to a predetermined temperature, for example, a temperature that takes into account the use of the energy storage elements 20 to be evaluated. The performance of the energy storage elements 60 can be evaluated from the results of the performance test on the multiple energy storage elements 60.

[0102] However, during performance testing, malfunctions can occur in the thermostatic chamber of the thermostatic bath. In conventional testing equipment, a short circuit could occur between two energy storage elements. Furthermore, performance testing under harsh temperature conditions can result in malfunctions such as one of the energy storage elements burning. These malfunctions in the thermostatic chamber can also affect other energy storage elements being tested that are unrelated to the cause of the malfunction. In other words, a single malfunction can prevent the performance of many energy storage elements placed in the thermostatic chamber from being properly evaluated. Furthermore, it may become necessary to re-perform a long-term performance test on many energy storage elements. If a long-term performance test needs to be re-performed, the evaluation results will be significantly delayed from the originally scheduled date.

[0103] To address these conventional problems, in one specific example of the present embodiment, the box body 30 that houses the energy storage elements 60 includes an insulating and flame-retardant material. By including an insulating and flame-retardant material in the box body 30 that houses the energy storage elements 60, it is possible to prevent the energy storage elements 60 housed in the housing chamber 30a from shorting out with other energy storage elements 60 placed in the temperature-controlled chamber 12 of the thermostatic bath 10. Furthermore, even if the energy storage elements 60 housed in the housing chamber 30a burn, it is possible to prevent the fire from spreading to other energy storage elements 60 placed in the temperature-controlled chamber 12. In other words, even if a malfunction occurs in one energy storage element 60 placed in the temperature-controlled chamber 12, it is possible to prevent the other energy storage elements 60 placed in the temperature-controlled chamber 12 from being affected by the malfunction. In other words, performance testing can be continued for energy storage elements 60 that are not subject to malfunction, and performance test results can be obtained as scheduled. Furthermore, since the energy storage elements 60 to be evaluated are placed in the housing chamber 30a of the box body 30, the energy storage elements 60 can be physically protected. As described above, the performance of a plurality of energy storage elements 60 can be evaluated stably and accurately by a performance test using one thermostatic chamber 10 .

[0104] In the above-described specific example, the box body 30 includes a wall 35 that defines an accommodation chamber 30a that accommodates the energy storage elements 60, and the wall 35 has insulating and flame-retardant properties. That is, an insulating and flame-retardant material is used for the wall 35 that defines the accommodation chamber 30a. According to this specific example, problems such as short circuits between the multiple energy storage elements 60 arranged in the thermostatic chamber 10 and the spread of fire in the thermostatic chamber 12 of the thermostatic chamber 10 can be more effectively prevented. Therefore, a performance test using one thermostatic chamber 10 can more accurately and stably evaluate the performance of the multiple energy storage elements 60.

[0105] In the above-described specific example, the box body 30 includes a wall 35 that defines an accommodation chamber 30a that accommodates the energy storage elements 60. The thickness of the wall is 0.5 mm or more, and may be 1.0 mm or more, 2.0 mm or more, or 5.0 mm or more. According to this specific example, problems such as fire spreading in the temperature-controlled chamber 12 of the temperature-controlled oven 10 can be more effectively suppressed. Therefore, a performance test using one temperature-controlled oven 10 can more accurately and stably evaluate the performance of multiple energy storage elements 60.

[0106] In the specific example described above, the glass transition temperature of the flame-retardant material is 100° C. or higher, or may be 110° C. or higher, 120° C. or higher, or 140° C. or higher. According to this specific example, problems such as fire spreading in the temperature-controlled chamber 12 of the temperature-controlled oven 10 can be more effectively suppressed. Therefore, a performance test using one temperature-controlled oven 10 can more accurately and stably evaluate the performance of multiple energy storage elements 60.

[0107] In one specific example of the present embodiment, the box body 30 includes a wall 35 that defines an accommodation chamber 30a that accommodates the energy storage element 60, and the wall 35 is provided with a through-hole 40. First, the energy storage element 60 to be evaluated is placed in the accommodation chamber 30a of the box body 30, thereby physically protecting the energy storage element 60. Furthermore, short circuits between the multiple energy storage elements 60 placed in the temperature-controlled chamber 12 of the thermostatic bath 10 can be suppressed. On the other hand, the through-hole 40 provided in the wall 35 allows gas to pass through the through-hole 40. In other words, deviations between the ambient temperature of the accommodation chamber 30a and the temperature-controlled chamber 12 can be suppressed. Therefore, the performance of the energy storage element 60 to be evaluated can be evaluated while the energy storage element 60 is placed in a predetermined temperature atmosphere. Furthermore, if the energy storage element 60 housed in the box body 30 can be observed from outside the box body 30 through the through-hole 40, it can be confirmed that no abnormalities have occurred in the energy storage element 60 to be evaluated during a performance test. As a result, the performance of a plurality of energy storage elements 60 can be evaluated accurately and stably by a performance test using one thermostatic chamber 10 .

[0108] In the specific example described above, the through hole 40 is configured as follows: The aperture ratio of the through hole is 10% or more, or may be 15% or more, 20% or more, 25% or more, or 30% or more. The through hole 40 includes two or more through holes positioned apart from each other. The wall portion 35 may include two plate portions facing each other with the storage chamber 30a in between, and the through hole 40 may include a through hole provided in each of the two plate portions. The wall portion 35 may include two plate portions facing each other with the storage chamber 30a in between, and the through hole 40 may include a through hole provided in each of the two plate portions facing directly opposite each other. The wall portion 35 may include two plate portions facing each other with the storage chamber 30a in between, and the through hole 40 may include a through hole provided in each of the multiple plate portions.

[0109] The above-described configuration of the through-holes 40 promotes the passage of gas through the through-holes 40, thereby more effectively preventing the ambient temperature of the storage chamber 30a from deviating from the ambient temperature of the temperature-controlled chamber 12 of the thermostatic chamber 10. Furthermore, it becomes easier to observe the energy storage elements 60 housed in the box body 30 from outside the box body 30 via the through-holes 40. It is possible to more accurately confirm that no abnormalities have occurred in the energy storage elements 60 during a performance test. As a result, the performance of multiple energy storage elements 60 can be evaluated more accurately and stably through a performance test using a single thermostatic chamber 10.

[0110] In the specific example described above, the electrical wiring 22 includes two electrical wirings 23A and 23B that connect to different tabs 66 of the energy storage element 60. According to this specific example, the entire energy storage element 60, including the two tabs 66, can be placed in the storage chamber 30a of the box body 30. Therefore, defects such as short circuits between the multiple energy storage elements 60 placed in the temperature-controlled chamber 12 of the temperature-controlled oven 10 and fire spread within the temperature-controlled oven 10 can be more effectively suppressed. Furthermore, the box body 30 can more effectively physically protect the energy storage elements 60. As a result, the performance of the multiple energy storage elements 60 can be evaluated more accurately and stably by a performance test using a single temperature-controlled oven 10.

[0111] In the specific example described above, the energy storage element box 20 further includes a terminal block 26 to which the electrical wiring 22 and the tab 66 of the energy storage element 60 are fixed. The terminal block 26 is attached to the box body 30. According to this specific example, the tab 66 of the energy storage element 60 and the electrical wiring 22 can be fixed to the terminal block 26 attached to the box body 30. As a result, movement of the energy storage element 60 and the electrical wiring 22 within the accommodation chamber 30a of the box body 30 can be suppressed. This more effectively suppresses defects such as short circuits within one energy storage element 60, short circuits between multiple energy storage elements 60, and physical damage to the energy storage elements 60. Therefore, a performance test using one thermostatic chamber 10 can more accurately and stably evaluate the performance of multiple energy storage elements 60.

[0112] In the specific example described above, the energy storage element 60 includes an electrode assembly 62 including a positive electrode plate and a negative electrode plate, an exterior material 64 that houses the electrode assembly 62, and a tab 66 that is electrically connected to the electrode assembly 62 and extends from the exterior material 64. The maximum distance between the exterior material 64 of the energy storage element 60 housed in the box body 30 and the box body 30 is 10% or less, or may be 8% or less, or 5% or less, of the length of the long side of the exterior material 64. According to this specific example, the gap between the box body 30 and the energy storage element 60 can be reduced. The box body 30 can be made smaller and lighter, making the energy storage element box 20 easier to handle. Furthermore, by reducing the volume of the storage chamber 30a, the temperature within the storage chamber 30a can be quickly brought closer to the temperature of the temperature-controlled chamber 12. Furthermore, a larger number of energy storage element boxes 20 and energy storage elements 60 can be housed in a temperature-controlled chamber 12 having a given volume. As a result, the performance of a plurality of energy storage elements 60 can be evaluated more accurately and efficiently by a performance test using one thermostatic chamber 10 .

[0113] In the specific example described above, the energy storage elements 60 housed in the box body 30 can be observed from outside the box body 30 via the through holes 40. According to this specific example, it is possible to confirm that no abnormalities have occurred in the energy storage elements 60 to be evaluated during the performance test. Therefore, the performance test using one thermostatic chamber 10 can more accurately and stably evaluate the performance of multiple energy storage elements 60.

[0114] In the present embodiment described above, the energy storage element box 20 is placed in the thermostatic chamber 10 where a performance test of the energy storage element 60 is conducted. The box 20 includes a box main body 30 that houses the energy storage element 60 and electrical wiring 22, 23A, and 23B that extend within the box main body 30 and electrically connect to the tabs 66 of the energy storage element 60. The energy storage element box 20 includes an insulating and flame-retardant material. According to the energy storage element box 20 of this embodiment, the energy storage element 60 to be evaluated is placed in the storage chamber 30a of the box main body 30, thereby physically protecting the energy storage element 60. Furthermore, since the box main body 30 that houses the energy storage element 60 includes an insulating and flame-retardant material, it is possible to prevent the energy storage element 60 housed in the storage chamber 30a from short-circuiting with other energy storage elements 60 placed in the thermostatic chamber 10. Even if the energy storage element 60 housed in the housing chamber 30a burns, it is possible to prevent the fire from spreading to other energy storage elements 60 arranged in the thermostatic chamber 10. As a result, the performance of a plurality of energy storage elements 60 can be evaluated accurately and stably through a performance test using one thermostatic chamber 10.

[0115] In the present embodiment described above, the test apparatus 5 is an apparatus for conducting a performance test of the energy storage elements 60. The test apparatus 5 includes a thermostatic chamber 10 and a plurality of energy storage element boxes 20 disposed within the thermostatic chamber 10. Each energy storage element box 20 is capable of housing an energy storage element 60. According to the test apparatus 5 of this embodiment, the energy storage elements 60 to be evaluated are disposed in the housing chamber 30a of the box body 30, thereby physically protecting the energy storage elements 60. Furthermore, it is possible to prevent the energy storage elements 60 housed within the housing chamber 30a from short-circuiting with other energy storage elements 60 disposed within the thermostatic chamber 10. As a result, the performance of a plurality of energy storage elements 60 can be evaluated accurately and stably through a performance test using a single thermostatic chamber 10.

[0116] Although one embodiment has been described with reference to specific examples, the above-described specific examples do not limit the present invention. The above-described embodiment can be implemented with various other specific examples, and various omissions, substitutions, changes, additions, etc. can be made without departing from the spirit of the present invention.

[0117] D1: first direction, D2: second direction, D3: third direction, 5: test equipment, 10: thermostatic bath, 12: thermostatic chamber, 14: partition wall, 16: shelf, 18: mounting base, 20: box for energy storage element, 22: electrical wiring, 23A: first main electrical wiring, 23B: second main electrical wiring, 24: thermocouple, 24a: fixture, 25: crimp terminal, 26: terminal block, 27: fixture, 28: electrical connector, 30: box body, 30a: storage chamber, 31: storage box section, 32: lid section, 35: wall section, 36: side plate section, 37: bottom plate section, 38: top plate section, 40: through hole, 42: support base, 43: table, 43a: through hole, 44: base, 60: energy storage element, 62: electrode body, 64: exterior material, 66: tab

Claims

1. A box for a storage element disposed in a thermostat where a performance test of the storage element is carried out, the box for a storage element comprising: a box body containing a material having insulation and flame retardancy and housing the storage element; and an electrical wiring extending within the box body and electrically connected to the storage element.

2. The box for a storage element according to claim 1, wherein the box body includes a wall portion partitioning a storage chamber for housing the storage element, and the thickness of the wall portion is 0.5 mm or more.

3. The box for a storage element according to claim 1, wherein the glass transition temperature of the material is 100°C or more.

4. The box for a storage element according to claim 1, wherein the box body includes a wall portion partitioning a storage chamber for housing the storage element, and a through hole is provided in the wall portion.

5. A box for a storage element disposed in a thermostat where a performance test of the storage element is carried out, the box for a storage element comprising: a box body including a wall portion partitioning a storage chamber for housing the storage element; and an electrical wiring extending within the box body and electrically connected to the storage element, and a through hole is provided in the wall portion.

6. The box for a storage element according to claim 4 or 5, wherein the opening ratio of the through hole is 10% or more.

7. The box for a storage element according to claim 4 or 5, wherein the through hole includes two or more through holes located apart from each other.

8. The box for a storage element according to claim 4 or 5, wherein the wall portion includes two plate portions facing each other with the storage chamber therebetween, and the through hole includes through holes provided in each of the two plate portions.

9. The box for a storage element according to claim 4 or 5, wherein the wall portion includes two plate portions facing each other with the storage chamber therebetween, and the through hole includes through holes provided in each of the two plate portions and facing each other.

10. The box for a storage element according to claim 4 or 5, wherein the wall portion includes a plurality of plate portions facing each other with the storage chamber therebetween, and the through hole includes through holes provided in each of the plurality of plate portions.

11. The box for a storage element according to claim 4 or 5, wherein the storage element housed in the box body can be observed from outside the box body through the through hole.

12. The storage element includes an electrode body, an exterior material housing the electrode body, and a tab electrically connected to the electrode body and extending from the exterior material. The electrical wiring includes two electrical wirings electrically connected to different tabs of the storage element. The box for a storage element according to claim 1 or 5.

13. The storage element includes an electrode body, an exterior member that houses the electrode body, and a tab that is electrically connected to the electrode body and extends from the exterior member, and further includes a terminal block to which the electrical wiring and the tab of the storage element are fixed, and the terminal block is attached to the box body. The box for a storage element according to claim 1 or 5.

14. The storage element includes an electrode body and an exterior member that houses the electrode body, and the maximum value of the distance between the exterior member of the storage element housed in the box body and the box body is 10% or less of the length of the long side of the exterior member. The box for a storage element according to claim 1 or 5.

15. A test device for performing a performance test of a storage element, comprising a thermostatic chamber and a plurality of boxes for storage elements arranged in the thermostatic chamber, and each box for a storage element can house the storage element. Test device.

16. A test device for performing a performance test of a storage element, comprising a thermostatic chamber and a plurality of boxes for storage elements arranged in the thermostatic chamber, and each box for a storage element is the box for a storage element according to claim 1 or 5. Test device.

17. An evaluation method for evaluating the performance of a storage element, comprising a step of arranging a plurality of boxes for storage elements each housing the storage element in a thermostatic chamber, and a step of performing a test on the storage element in the thermostatic layer. Evaluation method.

18. An evaluation method for evaluating the performance of a storage element, comprising a step of arranging a plurality of boxes for storage elements each housing the storage element in a thermostatic chamber, and a step of performing a test on the storage element in the thermostatic layer, and each box for a storage element is the box for a storage element according to claim 1 or 5. Evaluation method.

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