Energy storage device and energy storage system

Abstract

The application provides an energy storage device and an energy storage system. The energy storage device comprises a battery device and a box body, the box body has a cavity, the battery device is accommodated in the cavity, the box body comprises a wall plate, the wall plate participates in defining the cavity, the wall plate comprises a support structure, a reflection structure and a heat insulation structure, the support structure comprises a first plate body and a second plate body which are arranged at intervals along a first direction, the second plate body is located on a side of the first plate body away from the cavity, the reflection structure and the heat insulation structure are arranged between the first plate body and the second plate body and are stacked in the first direction, wherein the thermal conductivity of the heat insulation structure is less than or equal to the thermal conductivity of the support structure, the reflectivity of the reflection structure to infrared rays is greater than the reflectivity of the heat insulation structure to infrared rays, through the combination of the reflection structure and the heat insulation structure, the heat exchange between the cavity and the external environment is delayed in both heat conduction and heat radiation, the thickness of the heat insulation structure can be reduced, and the heat insulation performance of the wall plate of the box body can be enhanced.

Description

Technical Field

[0001] This application relates to the field of batteries, and in particular to an energy storage device and an energy storage system. Background Technology

[0002] Containerized energy storage systems are complete energy storage devices that highly integrate battery cells, battery management systems, energy storage converters, temperature control systems, fire protection systems, and electrical equipment into a standard container.

[0003] To cope with the continuous flames and high temperatures generated when batteries in an energy storage device experience thermal runaway, the enclosure wall panels should have good thermal insulation capabilities. Currently, the thermal insulation capabilities of the enclosure wall panels still need to be improved. Summary of the Invention

[0004] In view of the above problems, this application provides an energy storage device and an energy storage system that can improve the thermal insulation capacity of the wall panel to enhance the reliability of the energy storage device.

[0005] In a first aspect, this application provides an energy storage device, comprising: a battery device; a housing having a chamber in which the battery device is housed, the housing including a wall panel defining the chamber, the wall panel including a support structure, a reflective structure, and a heat insulation structure, the support structure including a first plate and a second plate spaced apart along a first direction, the second plate being located on the side of the first plate away from the chamber, the reflective structure and the heat insulation structure being disposed between the first plate and the second plate and stacked in the first direction, wherein the thermal conductivity of the heat insulation structure is less than or equal to the thermal conductivity of the support structure, the reflectivity of the reflective structure to infrared light is greater than the reflectivity of the heat insulation structure to infrared light, the reflective structure including at least one of a first reflective portion, a second reflective portion, and a third reflective portion, the first reflective portion being used to reflect near-infrared light, the second reflective portion being used to reflect mid-infrared light, and the third reflective portion being used to reflect far-infrared light.

[0006] In the embodiments of this application, the energy storage device includes a battery device and a housing. The housing has a chamber for accommodating the battery device. The housing includes a wall panel that defines the chamber. The wall panel includes a support structure, a reflective structure, and a heat insulation structure. The support structure includes a first plate and a second plate spaced apart along a first direction. The reflective structure and the heat insulation structure are disposed between the first plate and the second plate. The support structure serves to enhance the structural strength of the wall panel and reduce damage to the reflective structure and the heat insulation structure from external impacts. The thermal conductivity of the heat insulation structure is less than or equal to that of the support structure, thereby mitigating heat conduction between the chamber and the external environment. The reflective structure has a higher reflectivity for infrared light than the heat insulation structure, thereby suppressing heat radiation between the chamber and the external environment. In this embodiment, the combination of a reflective structure and a heat insulation structure delays heat exchange between the chamber and the external environment in terms of both heat conduction and heat radiation. This reduces the thickness of the heat insulation structure and enhances the heat insulation performance of the enclosure wall. The reflective structure includes at least one of a first reflective part, a second reflective part, and a third reflective part to suppress the radiative heat dissipation of at least one of near-infrared, mid-infrared, and far-infrared rays, thereby delaying heat exchange between the chamber and the external environment.

[0007] In some embodiments, the reflective structure includes a first reflective portion disposed on the side surface of the first plate away from the cavity.

[0008] In the embodiments of this application, on the one hand, the first reflective part is disposed on the first plate, eliminating the need to arrange a substrate layer for the first reflective part, thereby reducing the setting cost of the first reflective part; on the other hand, the first reflective part is placed close to the heat source in the cavity, which helps the first reflective part to reflect the λ1 wavelength infrared rays generated by the high temperature heat source in the cavity, thus delaying the heat exchange between the cavity and the external environment.

[0009] In some embodiments, the first reflective portion includes a first base layer and a coating layer disposed on the surface of the first base layer. The first base layer includes aluminum oxide, and the coating layer includes titanium dioxide or zirconium dioxide.

[0010] In the embodiment of this application, the first reflective part includes a first base layer and a covering layer disposed on the surface of the first base layer. The first base layer is used to fix the covering layer. The covering layer includes materials with high reflectivity to near-infrared rays, such as titanium dioxide or zirconium dioxide, to reflect near-infrared rays and delay thermal radiation heat exchange between the chamber and the external environment.

[0011] In some embodiments, the first reflective part has a near-infrared reflectivity of greater than or equal to 90%, and the wavelength λ1 of the near-infrared light satisfies 0.7μm≤λ1<2.5μm.

[0012] In the embodiment of this application, the first reflective part has a near-infrared reflectivity of greater than or equal to 90%, so that the first reflective part can reliably delay heat exchange between the chamber and the external environment through near-infrared radiation.

[0013] In some embodiments, the reflective structure includes a second reflective portion, which includes a support layer and reflective powder disposed on the support layer. The reflective powder is used to reflect mid-infrared rays, and the thermal conductivity of the support layer is less than that of the support structure.

[0014] In the embodiment of this application, the second reflective part includes a support layer and reflective powder disposed on the support layer. The support layer is used to support the reflective powder. The thermal conductivity of the support layer is less than that of the support structure. The support layer plays a role in delaying the heat conduction between the chamber and the external environment. The reflective powder can reflect mid-infrared rays to delay the heat radiation heat exchange between the chamber and the external environment.

[0015] In some embodiments, the support layer has a porous structure.

[0016] In the embodiments of this application, the porous support layer helps to scatter infrared radiation to suppress thermal radiation.

[0017] In some embodiments, the reflective powder includes at least one of SiC and boron carbide.

[0018] In the embodiments of this application, the reflective powder includes at least one of SiC and boron carbide, and the reflective powder plays the role of reflecting mid-infrared rays and suppressing thermal radiation.

[0019] In some embodiments, the second reflective portion has a reflectivity of 80% or more for mid-infrared light, and the wavelength λ2 of the mid-infrared light satisfies 2.5μm≤λ2<25μm.

[0020] In the embodiment of this application, the first reflective part has a mid-infrared reflectivity of greater than or equal to 80%, so that the second reflective part can reliably delay heat exchange between the chamber and the external environment through mid-infrared radiation.

[0021] In some embodiments, the reflective structure includes a third reflective portion, which includes a base layer and a heat-absorbing layer disposed on the base layer. The heat-absorbing layer is configured to decompose to form a reflective layer when the temperature reaches a first threshold. The reflective layer is used to reflect far-infrared rays.

[0022] In the embodiment of this application, the third reflective part includes a heat-absorbing layer. When the temperature reaches the first threshold, the heat-absorbing layer first decomposes to form a reflective layer. During the decomposition process, heat can be absorbed, and the generated reflective layer can reflect far-infrared rays to suppress heat radiation heat transfer. The third reflective part achieves a dual temperature control effect and reliably delays the heat transfer between the chamber and the external environment.

[0023] In some embodiments, the heat-absorbing layer comprises at least two materials with different thermal decomposition temperatures.

[0024] In the embodiments of this application, the heat-absorbing layer includes at least two materials with different thermal decomposition temperatures to broaden the heat-absorbing temperature range of the heat-absorbing layer.

[0025] In some embodiments, the heat-absorbing layer includes at least one of Mg(OH)2 and Al(OH)3.

[0026] In the embodiments of this application, the heat-absorbing layer includes at least one of Mg(OH)2 and Al(OH)3. When the temperature reaches a first threshold, Mg(OH)2 and Al(OH)3 decompose and absorb heat to form a metal oxide layer that reflects far-infrared rays. Furthermore, the decomposition temperatures of Mg(OH)2 and Al(OH)3 are complementary, which can broaden the decomposition temperature range of the heat-absorbing layer.

[0027] In some embodiments, the reflective layer has a far-infrared reflectivity of 85% or higher, and the wavelength λ3 of the far-infrared rays satisfies 25μm≤λ3<1000μm.

[0028] In the embodiments of this application, the reflective layer has a far-infrared reflectivity of 85% or higher, so that the reflective layer can reliably delay heat exchange between the chamber and the external environment through far-infrared radiation.

[0029] In some embodiments, the reflective structure includes a first reflective portion, a second reflective portion, and a third reflective portion, arranged sequentially in the direction from the first plate to the second plate.

[0030] In the embodiment of this application, a first reflective part, a second reflective part, and a third reflective part are arranged sequentially from the first plate to the second plate. On the one hand, the combination of the first reflective part, the second reflective part, and the third reflective part achieves full-band thermal radiation suppression. On the other hand, the sequential arrangement of the first reflective part, the second reflective part, and the third reflective part can suppress the infrared radiation generated by the heat source in the cavity along the short wavelength to the long wavelength, and more reliably suppress the temperature rise of the wall panel.

[0031] In some embodiments, the reflective structure includes two first reflective portions, two second reflective portions, and a third reflective portion. The two second reflective portions are disposed on both sides of the third reflective portion in a first direction, and the two first reflective portions are disposed on both sides of the two second reflective portions away from the third reflective portion.

[0032] In the embodiment of this application, two second reflective portions are disposed on both sides of the third reflective portion in its first direction, and two first reflective portions are disposed on both sides of the two second reflective portions away from the third reflective portion, so that the wall panel can delay the heat transfer from the cavity to the external environment when there is a high-temperature heat source in the cavity, and can also delay the heat transfer from the external environment to the cavity when there is a high-temperature heat source in the external environment.

[0033] In some embodiments, the reflective structure is located between the thermal insulation structure and the first plate.

[0034] In the embodiment of this application, the reflective structure is located between the heat insulation structure and the first plate. By suppressing infrared rays through the reflective structure, the heat resistance requirement of the heat insulation structure is reduced, which helps to reduce the size of the heat insulation structure, reduce the overall thickness of the wall panel, and improve the energy density of the energy storage device.

[0035] In some embodiments, the support structure further includes a fireproof layer disposed on the side of the first plate facing the chamber, the fireproof layer being configured to expand in volume to form a porous carbon layer when the temperature reaches a second threshold.

[0036] In the embodiment of this application, the support structure further includes a fireproof layer disposed on the side of the first plate facing the cavity. When the temperature reaches the second threshold, the fireproof layer expands in volume to form a porous carbon layer, which plays the role of heat insulation and flame retardancy.

[0037] In some embodiments, the wall panel further includes a connecting structure, which includes a frame and a heat-insulating part. The frame is disposed between the first plate and the second plate. The frame includes at least one perforation. A heat-insulating structure and at least a partially reflective structure are accommodated in the perforation. The frame is connected to at least one of the first plate and the second plate through the heat-insulating part. The thermal conductivity of the heat-insulating part is less than that of the frame.

[0038] In the embodiment of this application, the frame is disposed between the first plate and the second plate to enhance the overall structural strength of the wall panel. The heat insulation structure and at least part of the reflective structure are accommodated in the hollow hole to enhance the stability of the heat insulation structure and the reflective mechanism. The frame is connected to at least one of the first plate and the second plate through the heat-insulating part. The heat-insulating part delays the heat conduction path between the first plate and the second plate through the frame, and delays the heat transfer between the chamber and the external environment.

[0039] In some embodiments, the support structure further includes connecting portions, a plurality of connecting portions being disposed around the outer periphery of the frame and connected to the first plate and the second plate.

[0040] In the embodiments of this application, the connecting part is connected to the first plate and the second plate to enhance the structural strength of the wall panel.

[0041] Secondly, embodiments of this application provide an energy storage system, including the energy storage device of any of the embodiments of the first aspect described above. Attached Figure Description

[0042] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of preferred embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit the scope of this application. Furthermore, the same reference numerals denote the same parts throughout the drawings. In the drawings:

[0043] Figure 1 This is a schematic diagram of the battery device provided in the embodiments of this application;

[0044] Figure 2 This is a schematic diagram of the battery module provided in the application embodiment;

[0045] Figure 3 This is a schematic diagram of the energy storage device provided in the embodiments of this application;

[0046] Figure 4 This is a schematic diagram of the wall panel of the energy storage device provided in the embodiments of this application;

[0047] Figure 5 yes Figure 4 Sectional view at point AA;

[0048] Figure 6 yes Figure 5 Enlarged structural diagram at point B;

[0049] Figure 7 This is a partial structural schematic diagram of the wall panel of the energy storage device provided in the embodiments of this application;

[0050] Figure 8 This is a partial structural schematic diagram of the wall panel of the energy storage device provided in the embodiments of this application;

[0051] Figure 9 yes Figure 4 Sectional view at CC;

[0052] Figure 10 yes Figure 9 A magnified structural diagram at point D.

[0053] Explanation of reference numerals in the attached figures:

[0054] 1. Energy storage device;

[0055] 2. Battery assembly; 201. Battery module; 202. Housing; 2021. First housing section; 2022. Second housing section;

[0056] 3. Battery cells;

[0057] 4. Box body;

[0058] 5. Wall panel; 51. Supporting structure; 52. Reflective structure; 53. Thermal insulation structure; 54. Connecting structure; 511. First panel; 512. Second panel; 513. Fireproof layer; 514. Connecting part; 521. First reflective part; 522. Second reflective part; 523. Third reflective part; 541. Frame; 542. Perforated hole; 543. Thermal insulation part;

[0059] X, the first direction. Detailed Implementation

[0060] The embodiments of the technical solution of this application will now be described in detail with reference to the accompanying drawings. These embodiments are only used to more clearly illustrate the technical solution of this application and are therefore merely examples, and should not be used to limit the scope of protection of this application.

[0061] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the application; the terms “comprising” and “having”, and any variations thereof, in the specification, claims, and foregoing description of the drawings are intended to cover non-exclusive inclusion.

[0062] In the description of the embodiments of this application, technical terms such as "first" and "second" are used only to distinguish different objects and should not be construed as indicating or implying relative importance or implicitly specifying the number, specific order, or primary and secondary relationship of the indicated technical features. In the description of the embodiments of this application, "multiple" means two or more, unless otherwise explicitly defined.

[0063] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0064] In the description of the embodiments in this application, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, and B existing alone. Additionally, the character " / " in this document generally indicates that the preceding and following related objects have an "or" relationship.

[0065] In the description of the embodiments of this application, the term "multiple" refers to two or more (including two), similarly, "multiple sets" refers to two or more (including two sets), and "multiple pieces" refers to two or more (including two pieces).

[0066] In the description of the embodiments of this application, the technical terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the embodiments of this application and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the embodiments of this application.

[0067] In the description of the embodiments of this application, unless otherwise expressly specified and limited, technical terms such as "installation," "connection," "joining," and "fixing" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. For those skilled in the art, the specific meaning of the above terms in the embodiments of this application can be understood according to the specific circumstances.

[0068] In the embodiments of this application, the same reference numerals denote the same components, and for the sake of brevity, detailed descriptions of the same components are omitted in different embodiments. It should be understood that the thickness, length, width, and other dimensions of various components in the embodiments of this application shown in the accompanying drawings, as well as the overall thickness, length, width, and other dimensions of the integrated device, are merely illustrative and should not constitute any limitation on this application.

[0069] In the embodiments of this application, "parallel" includes not only the case of absolute parallelism, but also the case of approximate parallelism as commonly understood in engineering; similarly, "perpendicular" also includes not only the case of absolute perpendicularity, but also the case of approximate perpendicularity as commonly understood in engineering. For example, if the angle between two directions is 85°-95°, the two directions can be considered perpendicular; if the angle between two directions is 0°-5°, the two directions can be considered parallel.

[0070] In this application, "multiple" means two or more (including two).

[0071] This application provides an energy storage device including one or more battery devices to increase the voltage and capacity of the energy storage device. When the energy storage device includes multiple battery devices, the multiple battery devices are connected in parallel to increase the capacity of the energy storage device. Each battery device may include multiple individual battery cells, which are connected in series or in parallel.

[0072] In this embodiment of the application, the battery cell can be a secondary battery, which refers to a battery cell that can be recharged to activate the active materials and continue to be used after the battery cell has been discharged.

[0073] The battery cell can be a lithium-ion battery, sodium-ion battery, sodium-lithium-ion battery, lithium metal battery, sodium metal battery, lithium-sulfur battery, magnesium-ion battery, nickel-metal hydride battery, nickel-cadmium battery, lead-acid battery, etc., and the embodiments of this application are not limited to this.

[0074] Energy storage devices can be used in energy storage power stations, wind power generation systems, solar power generation systems, mobile power systems, or temporary power supply systems. Energy storage devices can store electrical energy as needed and output it when appropriate. For example, an energy storage device can store electrical energy during off-peak hours and provide power to relevant users or electrical equipment during peak hours. The energy storage system provided in this application embodiment can be any power system that requires energy storage devices.

[0075] In some embodiments, the energy storage device is an energy storage container or an energy storage cabinet.

[0076] In some embodiments, the energy storage device may include a housing and one or more battery devices housed within the housing.

[0077] In some embodiments, the energy storage device may include modules such as thermal management components, main control module, central control module, power distribution module, and fire protection components.

[0078] As an example, the thermal management component may include a liquid cooling unit that supplies coolant to each battery unit via piping to regulate the temperature of the individual battery cells.

[0079] As an example, the main control module can serve as the battery management unit for the battery cluster, used to monitor and manage the battery cluster. The main control module can monitor information such as the current, voltage, power, or temperature of the battery cluster. For instance, it can control the charging and discharging current and voltage of the battery cluster. The main control module includes modules such as an auxiliary battery management unit (SBMU) and a fusion switch.

[0080] As an example, the central control module can serve as the battery management unit for an energy storage device, used to monitor and manage the device. The central control module can monitor information such as the energy storage device's current, voltage, power, state of charge, or temperature. For instance, it can control the charging and discharging current and voltage of the energy storage device. As an example, the central control module includes modules such as an Insulation Monitoring Module (IMM), a Master Battery Management Unit (MBMU), an Ethernet (ETH) module, and a fiber optic conversion module.

[0081] As an example, a fire protection system includes control panels, detectors, alarm devices, etc., used to detect, alarm, or extinguish fires in energy storage systems.

[0082] As an example, the power distribution unit can be used to distribute power to the power modules of the energy storage device.

[0083] Containerized energy storage systems are complete energy storage devices that highly integrate individual battery cells, battery management systems, energy storage converters, temperature control systems, fire protection systems, and electrical equipment within a standard shipping container. To cope with the continuous flames and high temperatures generated during thermal runaway of the batteries within the energy storage device, the container walls must have excellent thermal insulation capabilities; currently, the thermal insulation capabilities of these container walls still need improvement.

[0084] In related technologies, the enclosure wall panels are made of double-layer steel plate sandwiched with rock wool filling. The low thermal conductivity of the rock wool filling layer can only delay heat transfer. However, the rock wool filling layer cannot effectively block heat radiation transfer. This results in the enclosure wall panels not being able to effectively isolate heat transfer between the chamber and the external environment. Furthermore, the rock wool filling layer needs to be made very thick, resulting in excessively thick enclosure wall panels.

[0085] Based on the aforementioned problems, embodiments of this application provide an energy storage device, including a battery device and a housing. The housing has a chamber for accommodating the battery device and includes wall panels that define the chamber. The wall panels include a support structure, a reflective structure, and a heat insulation structure. The support structure includes a first plate and a second plate spaced apart along a first direction. The reflective structure and the heat insulation structure are disposed between the first plate and the second plate. The support structure serves to enhance the structural strength of the wall panels and reduce damage to the reflective and heat insulation structures from external impacts. The thermal conductivity of the heat insulation structure is less than or equal to that of the support structure, thus mitigating heat conduction between the chamber and the external environment. The reflective structure has a higher reflectivity for infrared light than the heat insulation structure, thus suppressing heat radiation between the chamber and the external environment. In embodiments of this application, the combination of the reflective and heat insulation structures jointly delays heat exchange between the chamber and the external environment in terms of both heat conduction and heat radiation, thereby reducing the thickness of the heat insulation structure and enhancing the heat insulation performance of the housing wall panels.

[0086] Figure 1 A schematic diagram of the structure of a battery device 2 according to an embodiment of this application is shown.

[0087] The battery device 2 mentioned in the embodiments of this application may include one or more battery cell assemblies for providing voltage and capacity. A battery cell assembly may include multiple battery cells 3, which are connected in series, parallel, or mixed connections via a busbar.

[0088] In some embodiments, the battery cell assembly is typically formed by arranging a plurality of battery cells 3.

[0089] As an example, the battery cell assembly can be a battery module 201, which is formed by arranging and fixing multiple battery cells 3 to form an independent module. As an example, the battery module 201 can be formed by binding multiple battery cells 3 together with cable ties.

[0090] In some embodiments, the battery device 2 may be a battery pack, which includes a housing 202 and one or more battery cell assemblies, the battery cell assemblies being housed in the housing 202.

[0091] As an example, the battery cell assembly can be a battery module 201, which can be housed in the housing 202 by fixing the battery module 201 in the housing 202.

[0092] As an example, the battery cell assembly can also be housed in the housing 202 by directly fixing multiple battery cells 3 to the housing 202.

[0093] As an example, the housing 202 may include a first housing portion 2021 and a second housing portion 2022. The first housing portion 2021 and the second housing portion 2022 are fastened together, forming a closed space inside the housing 202 to accommodate the battery cell assembly. Here, "closed" refers to covering or closing, and can be either sealed or unsealed. The first housing portion 2021 may be an end cap or a bottom plate.

[0094] As an example, housing 202 may include end caps, a frame, and a base plate. The end caps and the base plate are respectively connected to the frame, so that the interior of housing 202 forms an enclosed space to accommodate the battery cell assembly.

[0095] In some embodiments, the housing 202 may be part of the vehicle's chassis structure. For example, a portion of the housing 202 may be at least a portion of the vehicle's floor, or a portion of the housing 202 may be at least a portion of the vehicle's crossbeams and longitudinal beams.

[0096] Figure 5 A schematic diagram of the structure of a battery module 201 according to an embodiment of this application is shown.

[0097] In some embodiments, such as Figure 1 and Figure 2 As shown, there are multiple battery cells 3, which are first connected in series, parallel, or in a mixed manner to form a battery module 201. The multiple battery modules 201 are then connected in series, parallel, or in a mixed manner to form a whole, which is housed in the casing 202.

[0098] Multiple battery cells 3 in the battery module 201 can be electrically connected through a busbar component to achieve parallel, series, or mixed connection of multiple battery cells 3 in the battery module 201.

[0099] Please see Figure 3 , Figure 4 and Figure 5 , Figure 3 This is a schematic diagram of the energy storage device provided in the embodiments of this application; Figure 4 This is a schematic diagram of the wall panel of the energy storage device provided in the embodiments of this application; Figure 5 yes Figure 4 Sectional view at point AA.

[0100] Firstly, such as Figures 3 to 5As shown, this application provides an energy storage device 1, which includes a battery device 2 and a housing 4. The housing 4 has a chamber in which the battery device 2 is housed. The housing 4 includes a wall panel 5, which helps to define the chamber. The wall panel 5 includes a support structure 51, a reflective structure 52, and a heat insulation structure 53. The support structure 51 includes a first plate 511 and a second plate 512 spaced apart along a first direction X. The second plate 512 is located on the side of the first plate 511 away from the chamber. The reflective structure 52 and the heat insulation structure 53 are disposed between the first plate 511 and the second plate 512 and are stacked in the first direction X. The thermal conductivity of the heat insulation structure 53 is less than or equal to the thermal conductivity of the support structure 51, and the reflectivity of the reflective structure 52 to infrared light is greater than that of the heat insulation structure 53 to infrared light.

[0101] In the embodiment of this application, the energy storage device 1 includes a battery device 2 and a housing 4. The housing 4 has a chamber for accommodating the battery device 2. The housing 4 includes a wall panel 5 that defines the chamber. The wall panel 5 includes a support structure 51, a reflective structure 52, and a heat insulation structure 53. The support structure 51 includes a first plate 511 and a second plate 512 spaced apart along a first direction X. The reflective structure 52 and the heat insulation structure 53 are disposed between the first plate 511 and the second plate 512. The support structure 51 is used to enhance the structural strength of the wall panel 5 and to reduce the damage to the reflective structure 52 and the heat insulation structure 53 caused by external impact. The thermal conductivity of the heat insulation structure 53 is less than or equal to the thermal conductivity of the support structure 51. The heat insulation structure 53 is used to mitigate heat conduction between the chamber and the external environment. The reflective structure 52 has a higher reflectivity for infrared light than the heat insulation structure 53. The reflective structure 52 is used to suppress heat radiation between the chamber and the external environment. In this embodiment, the combination of reflective structure 52 and heat insulation structure 53 delays heat exchange between the chamber and the external environment in terms of both heat conduction and heat radiation. This reduces the thickness of the heat insulation structure 53 and enhances the heat insulation performance of the wall panel 5 of the enclosure 4.

[0102] Optionally, the enclosure 4 includes interconnected enclosure walls and an enclosure door, the enclosure walls and the enclosure door together forming a chamber, and the enclosure door and the enclosure walls are movably connected. In this embodiment, the wall panel 5 can be at least a material of the enclosure wall, and / or in this embodiment, the wall panel 5 can be at least a portion of the material of the enclosure door. For example, in this embodiment, the wall panel 5 is the enclosure door of the enclosure 4. The specific size and shape of the wall panel 5 can be determined according to actual conditions.

[0103] Optionally, the support structure 51 includes a first plate 511 and a second plate 512 spaced apart along a first direction X. The support structure 51 is used to enhance the overall structural strength of the wall panel 5 and improve its resistance to external impacts. For example, the first plate 511 and the second plate 512 can be steel plates. For example, the surfaces of the first plate 511 and / or the second plate 512 are provided with an anti-corrosion coating to enhance the corrosion resistance of the support structure 51. For example, the anti-corrosion coating can be prepared by mixing epoxy resin with zinc-aluminum powder. For example, the thickness of the anti-corrosion coating can be 70μm, 80μm, 90μm, etc. Optionally, the materials and thicknesses of the first plate 511 and the second plate 512 can be the same or different.

[0104] In some embodiments, the support structure 51 further includes a fireproof layer 513, which is disposed on the side of the first plate 511 facing the cavity. The fireproof layer 513 is configured to expand in volume to form a porous carbon layer when the temperature reaches a second threshold, and the porous carbon layer plays a role in heat insulation and flame retardancy.

[0105] For example, fire-resistant layer 513 comprises graphene-modified ammonium polyphosphate. For example, the expansion ratio of fire-resistant layer 513 is greater than or equal to 10 when the temperature reaches the second threshold.

[0106] Optionally, a fireproof layer 513 is provided on the side of the second plate 512 away from the chamber. The fireproof layer 513 is used to reduce the damage of external heat sources to the battery device 2 in the chamber.

[0107] Optionally, the reflective structure 52 and the heat insulation structure 53 are disposed between the first plate 511 and the second plate 512. This allows the reflective structure 52 and the heat insulation structure 53 to work together to slow down heat transfer in both conduction and radiation along the heat transfer path between the interior and exterior environments. This improves the heat insulation performance of the wall panel 5 and helps reduce the size and cost of the heat insulation structure 53, as well as the thickness and weight of the wall panel 5.

[0108] For example, the thermal insulation structure 53 can be an ultra-fine glass fiber layer or a soluble fiber thermal insulation layer, etc. For example, the thickness of the thermal insulation structure 53 can be 10 mm, 15 mm, 20 mm, etc. For example, the thermal conductivity of the thermal insulation structure 53 is less than or equal to 0.02 W / (m•K) to ensure that the thermal insulation structure 53 reliably blocks heat conduction. For example, the compressive strength of the thermal insulation structure 53 is greater than or equal to 0.4 MPa.

[0109] Optionally, the reflectivity of the reflective structure 52 to infrared light is greater than that of the heat insulation structure 53 to infrared light, meaning that within a preset wavelength range, the reflectivity of the reflective structure 52 to infrared light is greater than that of the heat insulation structure 53 to infrared light. For example, the preset wavelength range can be any of the near-infrared wavelength range, the mid-infrared wavelength range, or the far-infrared wavelength range.

[0110] Optionally, when there is a high-temperature heat source in the cavity, the reflective structure 52 reflects the infrared rays generated by the heat source to delay the radiation of heat from the heat source to the environment outside the cavity; when there is a high-temperature heat source in the environment outside the cavity, the reflective structure 52 reflects the infrared rays generated by the heat source to delay the radiation of heat from the heat source to the environment inside the cavity.

[0111] Optionally, the orthographic projection of the reflective structure 52 in the first direction X covers the entire heat insulation structure 53, and the specific size and shape of the reflective structure 52 and the heat insulation structure 53 can be determined by the user.

[0112] Optionally, the reflective structure 52 is disposed between the first plate 511 and the heat insulation structure 53. When there is a high-temperature heat source in the cavity, the reflective structure 52 suppresses infrared rays, reduces the heat resistance requirement of the heat insulation structure 53, helps to reduce the size of the heat insulation structure 53, reduces the overall thickness of the wall panel 5, and improves the energy density of the energy storage device 1.

[0113] Optionally, the reflective structure 52 is disposed between the reflective second plate 512 and the heat insulation structure 53. When there is a high-temperature heat source in the external environment of the cavity, the reflective structure 52 suppresses infrared rays, reduces the heat resistance requirement of the heat insulation structure 53, helps to reduce the size of the heat insulation structure 53, reduces the overall thickness of the wall panel 5, and improves the energy density of the energy storage device 1.

[0114] Optionally, the reflectivity of the reflective structure 52 and the heat insulation structure 53 to infrared light can be measured by methods such as spectroscopy or radiometry.

[0115] For example, when testing the infrared reflectance of a sample by spectroscopic methods, the sample can be either the reflective structure 52 or the heat insulation structure 53. First, at least one of the infrared spectrometer or near-infrared spectrophotometer, the integrating sphere, and the infrared light source are started. Then, the standard reflector is fixed on the sample stage, placed in the sample position on the integrating sphere, and the scan is started. The reflected energy signal of the standard reflector at each wavelength is recorded. Er ( λ Then, remove the standard reflector, fix the sample on the sample stage, start the scan, and record the reflected energy signal of the sample at the same wavelength. Es ( λ Finally, the formula is called using the spectrometer's accompanying software. R ( λ )= Es ( λ )* R r ( λ ) / Er ( λ ), R r ( λ Given the known reflectivity of a standard reflector, calculate the reflectivity of the sample at each wavelength. R ( λ ).

[0116] Please see Figure 6 , Figure 6 yes Figure 5 A magnified structural diagram at point B in the middle.

[0117] In some embodiments, such as Figure 5 and Figure 6 As shown, the reflective structure 52 includes at least one of a first reflective portion 521, a second reflective portion 522, and a third reflective portion 523. The first reflective portion 521 is used to reflect near-infrared rays, the second reflective portion 522 is used to reflect mid-infrared rays, and the third reflective portion 523 is used to reflect far-infrared rays.

[0118] In these embodiments, the reflective structure 52 includes at least one of a first reflective portion 521, a second reflective portion 522, and a third reflective portion 523 to suppress radiative heat dissipation from at least one of near-infrared, mid-infrared, and far-infrared rays, thereby delaying heat exchange between the chamber and the external environment.

[0119] Optionally, in the near-infrared wavelength range, the reflectivity of the first reflective part 521 to infrared light is greater than that of the heat insulation structure 53 to infrared light. For example, the near-infrared wavelength range λ1 satisfies 0.7μm ≤ λ1 < 2.5μm, and the near-infrared reflectivity of the first reflective part 521 to near-infrared light is greater than or equal to 90%. The first reflective part 521 reliably delays heat exchange between the chamber and the external environment via near-infrared radiation.

[0120] Optionally, in the mid-infrared wavelength range, the reflectivity of the second reflective part 522 to infrared light is greater than that of the heat insulation structure 53 to infrared light. For example, the mid-infrared wavelength λ2 range satisfies 2.5μm ≤ λ2 < 25μm, and the reflectivity of the second reflective part 522 to mid-infrared light is greater than or equal to 80%. The second reflective part 522 reliably delays heat exchange between the chamber and the external environment via mid-infrared radiation.

[0121] Optionally, within the far-infrared wavelength range, the reflectivity of the third reflector 523 for infrared light is greater than that of the heat insulation structure 53. For example, the far-infrared wavelength λ3 range satisfies 25μm ≤ λ3 < 1000μm, and the far-infrared reflectivity of the third reflector 523 is greater than or equal to 80%. The third reflector 523 reliably delays heat exchange between the chamber and the external environment via far-infrared radiation.

[0122] Optionally, when the reflective structure 52 includes at least two of the first reflective portion 521, the second reflective portion 522, and the third reflective portion 523, the two are stacked and arranged along the first direction X.

[0123] Optionally, the reflective structure 52 may include one or more first reflective portions 521; the reflective structure 52 may include one or more second reflective portions 522; the reflective structure 52 may include one or more third reflective portions 523.

[0124] In some embodiments, such as Figure 5 and Figure 6 As shown, the reflective structure 52 includes a first reflective part 521, a second reflective part 522 and a third reflective part 523, arranged sequentially in the direction from the first plate 511 to the second plate 512.

[0125] In these embodiments, a first reflective part 521, a second reflective part 522, and a third reflective part 523 are arranged sequentially in the direction from the first plate 511 to the second plate 512. On the one hand, the combination of the first reflective part 521, the second reflective part 522, and the third reflective part 523 achieves full-band thermal radiation suppression. On the other hand, the sequential arrangement of the first reflective part 521, the second reflective part 522, and the third reflective part 523 can suppress the infrared radiation generated by the heat source in the cavity along the short wavelength to the long wavelength, and more reliably suppress the temperature rise of the wall panel 5.

[0126] Optionally, the first reflective part 521 has a greater reflectivity for near-infrared rays than its reflectivity for other wavelengths of infrared rays; the second reflective part 522 has a greater reflectivity for mid-infrared rays than its reflectivity for other wavelengths of infrared rays; and the third reflective part 523 has a greater reflectivity for far-infrared rays than its reflectivity for other wavelengths of infrared rays.

[0127] Specifically, the heat source in the cavity generates thermal radiation. The shorter the wavelength of infrared radiation, the stronger the energy. The strongest near-infrared radiation is reflected by the first reflector 521, which confines most of the thermal radiation energy within the cavity, suppresses heat transfer, and reduces the risk of other structural layers absorbing near-infrared radiation to generate heat and form new heat sources. Subsequently, mid-infrared and far-infrared radiation are reflected by the second reflector 522 and the third reflector 523 in sequence, suppressing the transmission of mid-infrared and far-infrared radiation and delaying radiative heat transfer.

[0128] Please see Figure 7 , Figure 7 This is a partial structural schematic diagram of the wall panel of the energy storage device provided in the embodiments of this application.

[0129] In some embodiments, such as Figure 7 As shown, the reflective structure 52 includes two first reflective parts 521, two second reflective parts 522 and a third reflective part 523. The two second reflective parts 522 are disposed on both sides of the third reflective part 523 in the first direction X, and the two first reflective parts 521 are disposed on both sides of the two second reflective parts 522 away from the third reflective part 523.

[0130] In these embodiments, two second reflective portions 522 are disposed on both sides of the third reflective portion 523 in the first direction X, and two first reflective portions 521 are disposed on both sides of the two second reflective portions 522 away from the third reflective portion 523, so that the wall panel 5 can delay the heat transfer from the cavity to the external environment when there is a high temperature heat source in the cavity, and can also delay the heat transfer from the external environment to the cavity when there is a high temperature heat source in the external environment.

[0131] Optionally, the two first reflective parts 521 are respectively the first sub-layer and the second sub-layer, and the two second reflective parts 522 are respectively the third sub-layer and the fourth sub-layer. The first sub-layer, the third sub-layer, the third reflective part 523, the fourth sub-layer, and the second sub-layer are arranged in sequence from the first plate 511 to the second plate 512.

[0132] Optionally, the thermal insulation structure 53 is located between the second sublayer and the second plate 512 to delay thermal conduction between the first plate 511 and the second plate 512.

[0133] Optionally, the reflective structure 52 includes two third reflective portions 523, which are respectively a fifth sub-layer and a sixth sub-layer, and the fifth and sixth sub-layers are located between the third sub-layer and the fourth sub-layer.

[0134] Optionally, the insulation structure 53 is located between the fifth and sixth sub-layers, so that regardless of whether the heat source is inside or outside the cavity, the reflective structure 52 can delay heat transfer by suppressing heat radiation in front of the insulation structure 53, thereby reducing the size requirement of the insulation structure 53.

[0135] In some embodiments, such as Figure 5 and Figure 6 As shown, the reflective structure 52 includes a first reflective part 521, which is disposed on the side surface of the first plate 511 facing away from the cavity.

[0136] In these embodiments, on the one hand, the first reflective part 521 is disposed on the first plate 511, eliminating the need for an additional substrate layer for the first reflective part 521 and reducing the cost of the first reflective part 521; on the other hand, the first reflective part 521 is placed close to the heat source inside the cavity, which helps the first reflective part 521 to reflect the λ1 wavelength infrared rays generated by the high temperature heat source inside the cavity and delays the heat exchange between the cavity and the external environment.

[0137] For example, the first reflective portion 521 is coated on the side of the first plate 511 facing away from the cavity.

[0138] For example, the first reflective portion 521 is a radiation-cooling coating.

[0139] For example, the thickness of the first reflective portion 521 can be 45μm, 50μm, 55μm, etc.

[0140] In some embodiments, the first reflective portion 521 includes a first base layer and a covering layer disposed on the surface of the first base layer. The first base layer includes aluminum oxide, and the covering layer includes titanium dioxide or zirconium dioxide. The first base layer is used to fix the covering layer, which includes materials with high reflectivity to near-infrared light, such as titanium dioxide or zirconium dioxide, to reflect near-infrared light and delay thermal radiation heat exchange between the chamber and the external environment.

[0141] Optionally, the first reflective part 521 is coated on the first plate 511 using gradient coating technology, with the bottom layer being an aluminum oxide layer and the surface layer being a titanium dioxide or zirconium dioxide doped layer.

[0142] Optionally, the first base layer may include aluminum oxide, which is chemically stable and has high hardness, significantly improving the wear resistance and corrosion resistance of the first reflective part 521. The second base layer may also include silicon dioxide, as silicon dioxide particles easily form a porous structure to scatter infrared radiation.

[0143] Optionally, the coating may include titanium dioxide or zirconium dioxide, wherein the proportion of titanium dioxide or zirconium dioxide in the coating is between 26% and 45% by mass.

[0144] In some embodiments, such as Figure 5 and Figure 6 As shown, the reflective structure 52 includes a second reflective part 522, which includes a support layer and reflective powder disposed on the support layer. The reflective powder is used to reflect mid-infrared rays, and the thermal conductivity of the support layer is less than that of the support structure 51.

[0145] In these embodiments, the second reflective part 522 includes a support layer and reflective powder disposed on the support layer. The support layer is used to support the reflective powder. The thermal conductivity of the support layer is less than that of the support structure 51. The support layer has the effect of delaying heat conduction between the chamber and the external environment. The reflective powder can reflect mid-infrared rays to delay radiative heat exchange between the chamber and the external environment.

[0146] Optionally, the support layer has a porous structure, which helps to scatter infrared radiation to suppress thermal radiation.

[0147] For example, the porosity of the support layer is greater than or equal to 75%.

[0148] For example, the thickness of the second reflective part 522 can be 15mm, 20mm, 25mm, etc.

[0149] Optionally, the reflective powder includes at least one of SiC and boron carbide, and the reflective powder plays the role of reflecting mid-infrared rays and suppressing thermal radiation.

[0150] Optionally, a soluble aluminosilicate fiber blanket is impregnated with SiC / BN nanoparticles and calcined at 800℃ to form a porous ceramic fiber layer, which serves as the second reflective part 522.

[0151] For example, porous ceramic fiber layer structures have high strength and are not prone to collapse or cracking under high temperature environments, exhibiting high stability.

[0152] For example, the density of soluble aluminum silicate fiber blankets is 120 kg / m³.

[0153] For example, SiC / BN nanoparticles are loaded onto the fiber surface via a sol-gel method to form a continuous ceramic network.

[0154] For example, in SiC / BN nanopowders, the mass ratio of SiC to BN is 1:1. BN acts as an insulator, improving impedance matching and allowing radiation to penetrate more easily; SiC, with its high dielectric constant, absorbs and attenuates energy. The heterogeneous interface formed by the two can greatly enhance the scattering and dissipation of mid-infrared radiation.

[0155] In some embodiments, such as Figure 5 and Figure 6 As shown, the reflective structure 52 includes a third reflective part 523, which includes a base layer and a heat-absorbing layer disposed on the base layer. The heat-absorbing layer is configured to decompose to form a reflective layer when the temperature reaches a first threshold. The reflective layer is used to reflect far-infrared rays.

[0156] In these embodiments, the third reflector 523 includes a heat-absorbing layer. When the temperature reaches a first threshold, the heat-absorbing layer first decomposes to form a reflective layer. During the decomposition process, heat can be absorbed, and the generated reflective layer can reflect far-infrared rays to suppress heat radiation heat transfer. The third reflector 523 achieves a dual temperature control effect and reliably delays the heat transfer between the chamber and the external environment.

[0157] For example, the base layer is a metal foil layer such as an aluminum foil layer or a copper foil layer.

[0158] Optionally, the heat-absorbing layer includes a heat-absorbing agent and a binder. The heat-absorbing agent decomposes when the temperature reaches a first threshold, and the heat-absorbing agent is bonded to the substrate by the binder. For example, the binder can be a silica sol film-forming agent. For example, the particle size D50 of the heat-absorbing agent is between 3 μm and 6 μm. For example, D50 is 3 μm, 4 μm, 5 μm, 6 μm, etc.

[0159] For example, the thickness of the heat-absorbing layer can be 0.3mm, 0.4mm, 0.5mm, 0.6mm, etc.

[0160] Optionally, the heat-absorbing layer includes at least two materials with different thermal decomposition temperatures to broaden the heat-absorbing temperature range of the heat-absorbing layer.

[0161] Optionally, the first threshold can be determined according to the actual situation. For example, the first threshold can be between 200-500℃. For example, the first threshold is 200℃, 300℃, 400℃, 500℃, etc.

[0162] Optionally, the heat-absorbing layer decomposes to generate a reflective layer with a far-infrared reflectivity of ≥85%, so that the reflective layer can reliably delay heat exchange between the chamber and the external environment through far-infrared radiation.

[0163] Optionally, the heat-absorbing layer includes at least one of Mg(OH)2 and Al(OH)3, or the heat-absorbing agent includes at least one of Mg(OH)2 and Al(OH)3. Mg(OH)2 and Al(OH)3 decompose upon heating to form a metal oxide reflective layer of MgO and Al2O3.

[0164] Optionally, the heat-absorbing layer includes a Mg(OH)2 and Al(OH)3 composite, where the thermal decomposition temperatures of Mg(OH)2 and Al(OH)3 are complementary (Al(OH)3 is about 200℃, and Mg(OH)2 is about 300℃ or higher), which can broaden the heat-absorbing temperature range of the heat-absorbing layer, and the decomposition products MgO and Al2O3 can synergistically form a dense heat-insulating and flame-retardant barrier.

[0165] For example, in a complex of Mg(OH)2 and Al(OH)3, the molar ratio of Mg²⁺ / Al³⁺ can be 3:1.

[0166] Please see Figure 8 , Figure 8 This is a partial structural schematic diagram of the wall panel of the energy storage device provided in the embodiments of this application.

[0167] In some embodiments, such as Figure 5 , Figure 6 and Figure 8 As shown, the wall panel 5 also includes a connecting structure 54, which includes a frame 541 and a heat-insulating part 543. The frame 541 is disposed between the first plate 511 and the second plate 512. The frame 541 includes at least one perforated hole 542. The heat-insulating structure 53 and at least a partially reflective structure 52 are accommodated in the perforated hole 542. The frame 541 is connected to at least one of the first plate 511 and the second plate 512 through the heat-insulating part 543. The thermal conductivity of the heat-insulating part 543 is less than that of the frame 541.

[0168] In these embodiments, the frame 541 is disposed between the first plate 511 and the second plate 512 to enhance the overall structural strength of the wall panel 5. The heat insulation structure 53 and at least part of the reflective structure 52 are accommodated in the perforated hole 542 to enhance the stability of the heat insulation structure 53 and the reflective mechanism. The frame 541 is connected to at least one of the first plate 511 and the second plate 512 through the heat-insulating part 543. The heat-insulating part 543 delays the conduction path of heat between the first plate 511 and the second plate 512 through the frame 541, thus delaying the heat transfer between the chamber and the external environment.

[0169] In related technologies, a frame 541 is disposed between a first plate 511 and a second plate 512, and heat is transferred between the first plate 511 and the second plate 512 through the frame 541. In the embodiment of this application, the frame 541 is connected to at least one of the first plate 511 and the second plate 512 through a heat-insulating part 543. The heat-insulating part 543 increases the thermal resistance between the first plate 511 and the second plate 512 to delay heat transfer between them.

[0170] Optionally, the frame 541 is made of fiberglass to reduce its weight and achieve lightweighting of the wall panel 5. For example, the fibers within the fiberglass frame are arranged in intersecting directions to balance the stress on the frame in all directions. For example, the axial angle of the fibers within the fiberglass frame 541 is ±5°.

[0171] For example, frame 541 is a rectangular frame.

[0172] For example, the heat-insulating part 543 is a nano-silver paste, and the thermal conductivity of the heat-insulating part 543 is less than or equal to 0.5 W / (m•K).

[0173] Optionally, the heat-insulating part 543 is disposed on both sides of the frame 541 to connect the first plate 511 and the second plate 512; or the heat-insulating part 543 is disposed on one side of the frame 541 in the first direction X to bond one of the first plate 511 and the second plate 512.

[0174] Optionally, the frame 541 is composed of multiple substrates to reduce the difficulty of frame processing. The substrates are bonded together using high-temperature resistant silicone adhesive.

[0175] Optionally, the thermal insulation structure 53 includes one or more perforations 542. For example, the number of perforations 542 can be 1, 2, 3, 4, etc.

[0176] Optionally, the reflective structure 52 includes a first reflective portion 521, a second reflective portion 522, and a third reflective portion 523, with the heat insulation structure 53 located between the reflective structure 52 and the second plate 512. In the case where the heat insulation structure 53 includes at least two perforations 542, the heat insulation structure 53 is divided into multiple heat insulation substructures, each disposed within a perforation 542. The third reflective portion 523 is divided into multiple third sub-parts, each disposed within a perforation 542. The second reflective portion 522 is divided into multiple second sub-parts, each disposed within a perforation 542; or the second reflective portion 522 covers each perforation 542. The first sub-reflective portion is a single-layer structure, covering each perforation 542.

[0177] For example, the frame 541 is connected to the second plate 512 via the heat-insulating part 543.

[0178] For example, the first reflective part 521 is a coating disposed on the first plate 511, and the frame 541 is bonded to the first reflective part 521 through the heat-insulating part 543 to fix it to the first plate 511; or the frame 541 passes through the first reflective part 521 and is threadedly connected to the first plate 511.

[0179] Optional, please refer to Figure 9 and Figure 10 , Figure 9 yes Figure 4 Sectional view at CC; Figure 10 yes Figure 9 A magnified structural diagram at point D. (See diagram below.) Figure 9 and Figure 10 As shown, the support structure 51 also includes connecting parts 514. Multiple connecting parts 514 are arranged around the outer periphery of the frame 541 and connected to the first plate 511 and the second plate 512 to enhance the structural strength of the wall panel 5.

[0180] Optionally, the connecting part 514 may be made of metal to improve its structural strength. For example, the connecting part 514 may be made of aluminum, copper, stainless steel, etc.

[0181] Secondly, embodiments of this application provide an energy storage system, including the energy storage device of any of the embodiments of the first aspect described above.

[0182] In some embodiments, such as Figures 1 to 10 As shown, the energy storage device 1 includes a battery device 2 and a housing 4. The housing 4 has a chamber in which the battery device 2 is housed. The housing 4 includes a wall panel 5, which defines the chamber. The wall panel 5 includes a support structure 51, a reflective structure 52, a heat insulation structure 53, and a connecting structure 54. The support structure 51 includes a first plate 511 and a second plate 512 spaced apart along a first direction X. The second plate 512 is located on the side of the first plate 511 away from the chamber. The reflective structure 52 and the heat insulation structure 53 are disposed between the first plate 511 and the second plate 512. The thermal conductivity of the heat insulation structure 53 is less than or equal to the thermal conductivity of the support structure 51. The reflective structure 52 is located on the side of the heat insulation structure 512 away from the chamber. Between structure 53 and the first plate 511, the reflective structure 52 has a higher reflectivity for infrared light than the heat insulation structure 53. The reflective structure 52 includes a first reflective part 521, a second reflective part 522, and a third reflective part 523 arranged sequentially from the first plate 511 to the second plate 512. The first reflective part 521 has a near-infrared reflectivity greater than or equal to 90%, and the near-infrared wavelength λ1 satisfies 0.7μm ≤ λ1 < 2.5μm. The first reflective part 521 is disposed on the surface of the first plate 511 facing away from the cavity. The first reflective part 521 includes a first base layer and a covering layer disposed on the surface of the first base layer. The second reflective part 522 includes an aluminum oxide layer and a coating layer comprising titanium dioxide or zirconium dioxide. The second reflective part 522 includes a support layer and reflective powder disposed on the surface of the support layer. The reflective powder is used to reflect mid-infrared radiation. The thermal conductivity of the support layer is less than that of the support structure 51. The support layer has a porous structure. The reflective powder includes at least one of SiC and boron carbide. The second reflective part 522 has a mid-infrared reflectivity greater than or equal to 80%, and the wavelength λ2 of the mid-infrared radiation satisfies the condition 2.5μm ≤ λ2 < 25μm. The third reflective part 523 includes a base layer and a heat-absorbing layer disposed on the base layer. The heat-absorbing layer includes Mg(OH)2 and Al(OH)3. The heat-absorbing layer is configured to reflect mid-infrared radiation at a temperature reaching a first... At the threshold, a reflective layer is formed by decomposition. The reflective layer is used to reflect far-infrared rays. The reflectivity of the reflective layer to far-infrared rays is greater than or equal to 85%. The wavelength λ3 of the far-infrared rays satisfies 25μm≤λ3<1000μm. The connecting structure 54 includes a frame 541 and a heat-insulating part 543. The frame 541 is disposed between the first plate 511 and the second plate 512. The frame 541 includes at least one hollow hole 542. The heat-insulating structure 53 and at least a partial reflective structure 52 are accommodated in the hollow hole 542. The frame 541 is connected to at least one of the first plate 511 and the second plate 512 through the heat-insulating part 543. The thermal conductivity of the heat-insulating part 543 is less than that of the frame 541.

[0183] In these embodiments, the energy storage device 1 includes a battery device 2 and a housing 4. The housing 4 has a chamber for accommodating the battery device 2. The housing 4 includes a wall panel 5 that defines the chamber. The wall panel 5 includes a support structure 51, a reflective structure 52, and a heat insulation structure 53. The support structure 51 includes a first plate 511 and a second plate 512 spaced apart along a first direction X. The reflective structure 52 and the heat insulation structure 53 are disposed between the first plate 511 and the second plate 512. The support structure 51 serves to enhance the structural strength of the wall panel 5 and reduce damage to the reflective structure 52 and the heat insulation structure 53 from external impacts. The thermal conductivity of the heat insulation structure 53 is less than or equal to that of the support structure 51, thereby mitigating heat conduction between the chamber and the external environment. The reflective structure 52 has a higher reflectivity for infrared light than the heat insulation structure 53, thereby suppressing heat radiation between the chamber and the external environment. In this embodiment, the combination of the reflective structure 52 and the heat insulation structure 53 delays the heat exchange between the chamber and the external environment in terms of both heat conduction and heat radiation. This reduces the thickness of the heat insulation structure 53 and enhances the heat insulation performance of the wall panel 5.

[0184] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and not to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. These modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application, and they should all be covered within the scope of the claims and specification of this application. In particular, as long as there is no structural conflict, the various technical features mentioned in the embodiments can be combined in any way. This application is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. An energy storage device, characterized in that, include: Battery device; A housing having a chamber in which the battery device is housed, the housing including wall panels defining the chamber, the wall panels including a support structure, a reflective structure, and a heat-insulating structure, the support structure including a first plate and a second plate spaced apart along a first direction, the second plate being located on the side of the first plate away from the chamber, the reflective structure and the heat-insulating structure being disposed between the first plate and the second plate and stacked in the first direction. Wherein, the thermal conductivity of the heat insulation structure is less than or equal to that of the supporting structure, the reflectivity of the reflective structure to infrared light is greater than that of the heat insulation structure to infrared light, and the reflective structure includes a first reflective part, a second reflective part, and a third reflective part. The first reflective part is used to reflect near-infrared light, the second reflective part is used to reflect mid-infrared light, and the third reflective part is used to reflect far-infrared light. In the direction from the first plate to the second plate, one first reflective part, one second reflective part, and one third reflective part are arranged sequentially, and the reflective structure is located between the heat insulation structure and the first plate.

2. The energy storage device according to claim 1, characterized in that, The first reflective part is disposed on the side surface of the first plate that is away from the cavity.

3. The energy storage device according to claim 2, characterized in that, The first reflective portion includes a first base layer and a coating layer disposed on the surface of the first base layer. The first base layer includes aluminum oxide, and the coating layer includes titanium dioxide or zirconium dioxide.

4. The energy storage device according to claim 2, characterized in that, The first reflective part has a reflectivity of 90% or more for near-infrared light, and the wavelength λ1 of the near-infrared light satisfies 0.7μm≤λ1<2.5μm.

5. The energy storage device according to claim 1, characterized in that, The second reflective part includes a support layer and reflective powder disposed on the support layer. The reflective powder is used to reflect mid-infrared rays. The thermal conductivity of the support layer is less than that of the support structure.

6. The energy storage device according to claim 5, characterized in that, The support layer has a porous structure.

7. The energy storage device according to claim 5, characterized in that, The reflective powder includes at least one of SiC and boron carbide.

8. The energy storage device according to claim 5, characterized in that, The second reflective part has a reflectivity of 80% or more for mid-infrared light, and the wavelength λ2 of the mid-infrared light satisfies 2.5μm≤λ2<25μm.

9. The energy storage device according to claim 1, characterized in that, The third reflective part includes a second base layer and a heat-absorbing layer disposed on the second base layer. The heat-absorbing layer is configured to decompose to form a reflective layer when the temperature reaches a first threshold. The reflective layer is used to reflect far-infrared rays.

10. The energy storage device according to claim 9, characterized in that, The heat-absorbing layer comprises at least two materials with different thermal decomposition temperatures.

11. The energy storage device according to claim 9, characterized in that, The heat-absorbing layer includes at least one of Mg(OH)2 and Al(OH)3.

12. The energy storage device according to claim 9, characterized in that, The reflective layer has a reflectivity of 85% or higher for far-infrared rays, and the wavelength λ3 of the far-infrared rays satisfies 25μm≤λ3<1000μm.

13. The energy storage device according to claim 12, characterized in that, The reflective structure includes two first reflective portions, two second reflective portions, and a third reflective portion. The two second reflective portions are disposed on both sides of the third reflective portion in the first direction, and the two first reflective portions are disposed on both sides of the two second reflective portions away from the third reflective portion.

14. The energy storage device according to claim 1, characterized in that, The support structure also includes a fireproof layer, which is disposed on the side of the first plate facing the chamber. The fireproof layer is configured to expand in volume to form a porous carbon layer when the temperature reaches a second threshold.

15. The energy storage device according to claim 1, characterized in that, The wall panel further includes a connecting structure, which includes a frame and a heat-insulating part. The frame is disposed between the first plate and the second plate, and the frame includes at least one perforated hole. The heat-insulating structure and at least part of the reflective structure are accommodated in the perforated hole. The frame is connected to at least one of the first plate and the second plate through the heat-insulating part. The thermal conductivity of the heat-insulating part is less than that of the frame.

16. The energy storage device according to claim 15, characterized in that, The support structure also includes connecting parts, a plurality of which are arranged around the outer periphery of the frame and connected to the first plate and the second plate.

17. An energy storage system, characterized in that, It includes a power conversion device and an energy storage device as described in any one of claims 1-16, wherein the power conversion device is used to electrically connect the power generation device and the energy storage device.

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