Upper cover structure and battery pack

Abstract

The invention relates to an upper cover structure and a battery pack. The battery pack comprises a battery cell explosion-proof valve, the upper cover structure comprises a body, the body is provided with a reinforcing rib which corresponds to the battery cell explosion-proof valve and protrudes in the direction away from the battery cell explosion-proof valve, and a groove is formed in the side, close to the battery cell explosion-proof valve, of the reinforcing rib of the body; and the aerogel layer is fixedly arranged in the groove. The protruding reinforcing ribs arranged on the body correspond to the battery cell explosion-proof valve in position, the grooves are formed in the sides, close to the battery cell explosion-proof valve, of the reinforcing ribs, the aerogel layers are fixedly arranged in the grooves, and aerogel serves as an efficient heat insulation material and can effectively resist direct impact of high-temperature jet flow generated when the battery cell is in thermal runaway on the upper cover. The carbon fiber layer is prevented from being decomposed or burnt through at high temperature, so that the safety requirement of the battery pack in the aviation field is met.

Description

Technical Field

[0001] This application relates to the field of battery technology, and in particular to top cover structures and battery packs. Background Technology

[0002] With the rapid development of new energy technologies, battery packs, as key components for energy storage and conversion, have been widely used in various fields such as electric vehicles, electric aviation, and energy storage systems. Different application scenarios have placed diverse performance demands on battery packs, especially in terms of lightweighting, thermal safety, electrical safety, and electromagnetic compatibility.

[0003] In the field of electric aviation, battery pack design faces extreme challenges. Because aircraft are extremely sensitive to weight, battery packs must be incredibly lightweight to reduce energy consumption and improve flight efficiency. At the same time, aviation safety standards impose extremely high requirements on the thermal and electrical safety of battery packs. The battery pack cover, as a crucial component protecting the battery cells and maintaining the structural integrity of the battery pack, directly impacts the overall safety and reliability of the battery pack.

[0004] Currently, to meet the demand for lightweighting, battery pack covers are mostly made of composite materials, among which carbon fiber composites are highly favored due to their low density and high strength. However, carbon fiber composites have poor stability at high temperatures. In the event of thermal runaway in the battery pack, the carbon fiber composite material may decompose at high temperatures, producing smoke, or even burn through to expose open flames, posing a serious threat to aviation safety. Summary of the Invention

[0005] Therefore, it is necessary to provide a cover structure and battery pack to address the problem that the carbon fiber composite material of conventional battery pack covers may decompose at high temperatures, generating smoke or even burning through to expose open flames, posing a serious threat to aviation safety.

[0006] This application provides a top cover structure for use in a battery pack, the battery pack including a cell explosion-proof valve, the top cover structure including: a body, the body having a reinforcing rib corresponding to the cell explosion-proof valve and protruding in a direction away from the cell explosion-proof valve, the body forming a groove on the side of the reinforcing rib near the cell explosion-proof valve; and an aerogel layer fixedly disposed in the groove.

[0007] According to one embodiment of this application, the body includes: a plurality of carbon fiber layers stacked together; a glass fiber insulation layer, wherein the glass fiber insulation layer is stacked with the carbon fiber layers and is located on the side of the carbon fiber layers near the cell explosion-proof valve.

[0008] According to one embodiment of this application, the body further includes a conductive layer, which is stacked with the carbon fiber layer and the glass fiber insulation layer, and at least a portion of the conductive layer is located on the side of the glass fiber insulation layer opposite to the cell explosion-proof valve.

[0009] According to one embodiment of this application, the battery pack further includes a lower housing, the cell explosion-proof valve is located in the lower housing, the body has a protective area and a connection area surrounding the outside of the protective area, the connection area is used to connect with the lower housing, the glass fiber insulation layer at least covers the protective area, and a portion of the conductive layer is exposed on the side of the connection area that is connected to the lower housing.

[0010] According to one embodiment of this application, in the protective area, the conductive layer is located between the glass fiber insulation layer and the carbon fiber layer, or the conductive layer is located between two adjacent carbon fiber layers; in the connection area, the conductive layer extends to the side of the carbon fiber layer near the lower housing.

[0011] According to one embodiment of this application, a portion of the carbon fiber layers are located in the connection region and the protective region, while another portion of the carbon fiber layers are located in the connection region, such that the total thickness of the carbon fiber layers in at least a portion of the body in the connection region is greater than the total thickness of the carbon fiber layers in the protective region.

[0012] According to one embodiment of this application, the conductive layer covers the side of the body away from the cell explosion-proof valve, and the conductive layer extends from the edge of the body to the side where the connection area is connected to the lower housing.

[0013] According to one embodiment of this application, the conductive layer comprises a metal mesh or nickel-plated carbon fiber.

[0014] According to one embodiment of this application, the thickness of the glass fiber insulation layer is greater than or equal to 0.1 mm and less than or equal to 0.4 mm.

[0015] This application also provides a battery pack, including: a lower housing; a cell explosion-proof valve located inside the lower housing; and an upper cover structure according to the above embodiment, the upper cover structure being connected to the lower housing.

[0016] The aforementioned top cover structure and battery pack have raised reinforcing ribs on the main body that correspond to the positions of the cell explosion-proof valves. A groove is formed on the side of the reinforcing ribs near the cell explosion-proof valves, and an aerogel layer is fixedly installed in the groove. As a highly efficient heat insulation material, aerogel can effectively resist the direct impact of the high-temperature jet generated during cell thermal runaway on the top cover, preventing the carbon fiber layer from decomposing or burning through at high temperatures, thereby meeting the safety requirements of the battery pack in the aviation field. Attached Figure Description

[0017] Figure 1 This is an exploded view of a battery pack provided in an embodiment of this application.

[0018] Figure 2 This is a top view of the cover structure provided in one embodiment of this application.

[0019] Figure 3 A cross-sectional view of the body provided in an embodiment of this application.

[0020] Figure 4 A partial cross-sectional view of the cover structure provided in an embodiment of this application.

[0021] Figure 5 A partial cross-sectional view of the cover structure provided in another embodiment of this application.

[0022] Figure 6 A partial cross-sectional view of the cover structure provided in another embodiment of this application.

[0023] Figure 7 A partial cross-sectional view of the cover structure provided in another embodiment of this application.

[0024] Figure label:

[0025] 100. Top cover structure; 110. Body; 111. Reinforcing rib; 112. Groove; 113. Carbon fiber layer; 114. Glass fiber insulation layer; 115. Conductive layer; 116. Protective area; 117. Connection area; 120. Aerogel layer;

[0026] 200. Battery cell explosion-proof valve;

[0027] 300. Lower housing; 310. Connecting part. Detailed Implementation

[0028] To make the above-mentioned objectives, features, and advantages of this application more apparent and understandable, the specific embodiments of this application are described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of this application. However, this application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of this application. Therefore, this application is not limited to the specific embodiments disclosed below.

[0029] In the description of this application, it should be understood that if terms such as "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential" appear, these terms indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.

[0030] Furthermore, where the terms "first" and "second" appear, these terms are for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined with "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, where the term "multiple" appears, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0031] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., 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, unless otherwise expressly limited. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0032] In this application, unless otherwise expressly specified and limited, the use of descriptions such as "above" or "below" the second feature indicates that the first and second features are in direct contact or indirect contact via an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. Similarly, "below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0033] It should be noted that if an element is referred to as being "fixed to" or "set on" another element, it can be directly on the other element or there may be an intervening element. If an element is considered to be "connected to" another element, it can be directly connected to the other element or there may be an intervening element. If so, the terms "vertical," "horizontal," "upper," "lower," "left," "right," and similar expressions used in this application are for illustrative purposes only and do not represent the only possible implementation.

[0034] Combination Figures 1 to 3 The top cover structure 100 provided in one embodiment of this application is applied to a battery pack, which includes a cell explosion-proof valve 200. The cell explosion-proof valve 200 is a safety valve inside the power battery. When the cell experiences thermal runaway or excessive internal pressure, the explosion-proof valve will actively open to release high-pressure gas and heat to prevent the cell from exploding. However, the high-temperature jet (up to several hundred degrees Celsius) released when the explosion-proof valve opens will directly impact the battery pack top cover. If the top cover material has insufficient temperature resistance, it may cause resin decomposition, smoke, or even open flame, seriously threatening aviation safety. The top cover structure 100 of this embodiment aims to solve this problem.

[0035] The upper cover structure 100 includes a body 110 and an aerogel layer 120. The body 110 is provided with a reinforcing rib 111 that corresponds to the cell explosion-proof valve 200 and protrudes in a direction away from the cell explosion-proof valve 200. A groove 112 is formed on the side of the body 110 near the cell explosion-proof valve 200 of the reinforcing rib 111. The aerogel layer 120 is fixedly disposed in the groove 112.

[0036] In this embodiment, the raised reinforcing rib 111 is formed by bending the body 110, reducing secondary processing steps (such as welding, riveting, etc.) and improving production efficiency. Furthermore, it can increase the structural strength of the body 110 without increasing the number of layers constituting the body 110 (e.g., carbon fiber layer 113). In addition, a groove 112 can be formed on the side of the reinforcing rib 111 near the cell explosion-proof valve 200, which facilitates the positioning of the aerogel layer 120, ensures the protective effect, and improves the reliability of thermal runaway protection. The sidewall of the groove 112 provides mechanical constraint to the aerogel layer 120, ensuring its stability under complex working conditions.

[0037] For ease of description, the length direction of the body 110 is defined as the X direction, the width direction of the body 110 is defined as the Y direction, and the thickness direction of the body 110 is defined as the Z direction.

[0038] The shape and size of the reinforcing rib 111 can be flexibly adjusted according to the arrangement structure of the battery cell explosion-proof valve 200, and the aerogel layer 120 is adapted to the groove 112 formed by the reinforcing rib 111. For example, the reinforcing rib 111 extends along the X direction and is provided at equal intervals along the Y direction, with each reinforcing rib 111 corresponding to an aerogel layer 120. The aerogel layer 120 is fixed in the groove 112 by means such as adhesive. The length direction of the aerogel layer 120 is along the X direction, the width direction is along the Y direction, and the thickness direction is along the Z direction.

[0039] Aerogel, as a nanoporous thermal insulation material, has low thermal conductivity and can effectively block the transfer of high temperature during thermal runaway. By setting an aerogel layer 120 in the groove 112, the direct damage of the high-temperature jet to the body 110 during thermal runaway of the battery cell can be effectively resisted. The aerogel layer 120 adds little weight after being embedded in the body 110, which can balance lightweight and structural stability.

[0040] In some embodiments, the density of the aerogel layer 120 on the side closer to the cell explosion-proof valve 200 is greater than the density on the side farther from the cell explosion-proof valve 200.

[0041] For example, the aerogel layer 120 includes a first constituent layer and a second constituent layer stacked with the first constituent layer. The first constituent layer is located on the side of the second constituent layer near the cell explosion-proof valve 200, and the density of the first constituent layer is greater than the density of the second constituent layer. For example, the density of the first constituent layer is 0.2 g / cm³-0.3 g / cm³, and the density of the second constituent layer is 0.05 g / cm³-0.1 g / cm³.

[0042] For example, the density of the aerogel layer 120 decreases from the side closer to the cell explosion-proof valve 200 to the side farther away from the cell explosion-proof valve 200.

[0043] In this embodiment, the aerogel layer 120 has a higher density on the side closer to the cell explosion-proof valve 200, which enhances its impact resistance, while the density on the side farther away is lower, improving its thermal insulation efficiency. Furthermore, this increases the stability of the aerogel layer 120, making it less prone to breakage under high-temperature jet impact.

[0044] Optionally, the aerogel layer 120 is coated with a ceramic-based high-temperature resistant coating (such as a zirconia coating) to further block direct burning by open flame.

[0045] Combination Figure 4 In some embodiments, the body 110 includes multiple stacked carbon fiber layers 113. Exemplarily, resin is used as both a binder and a matrix to bond the high-strength carbon fiber layers 113 together. Simultaneously, the mechanical properties are optimized through the layup direction, ultimately achieving a combination of lightweight and high strength. Utilizing the high strength and lightweight characteristics of carbon fiber, the stringent requirements for structural strength and weight of the battery pack are met.

[0046] The main body 110 also includes a glass fiber insulation layer 114, which is stacked with a carbon fiber layer 113 and located on the side of the carbon fiber layer 113 near the cell explosion-proof valve 200.

[0047] The glass fiber insulation layer 114 can completely cover the side of the carbon fiber layer 113 near the cell explosion-proof valve 200, or it can only cover a part of the area of ​​the carbon fiber layer 113 near the cell explosion-proof valve 200. The specific design can be flexibly made according to the insulation requirements, and no specific limitation is made here.

[0048] The carbon fiber layer 113 and the glass fiber insulation layer 114 can be integrally formed through a co-curing process to ensure the interlayer bonding strength.

[0049] It is understandable that battery structural components need to meet high insulation and withstand voltage requirements, but carbon fiber has poor insulation performance. In this embodiment, a glass insulation layer is set on the side of the carbon fiber layer 113 near the cell explosion-proof valve 200. The carbon fiber layer 113 serves as the main structural support layer, providing high strength and high rigidity, while the glass fiber insulation layer 114 serves as the electrical insulation layer. The combination of the two can simultaneously solve the problems of low dielectric properties of carbon fiber and weak strength of glass fiber.

[0050] Optionally, the thickness of the glass fiber insulation layer 114 is greater than or equal to 0.1 mm and less than or equal to 0.4 mm. For example, the thickness of the glass fiber insulation layer 114 is 0.1 mm, 0.2 mm, 0.3 mm, or 0.4 mm. A thickness of the glass fiber insulation layer 114 within the aforementioned range can effectively improve the insulation and withstand voltage performance of the cover structure 100 itself, covering scenarios with different withstand voltage intensities, and has minimal impact on the overall structural strength and weight of the cover structure 100.

[0051] Combination Figures 5 to 7 In some embodiments, the body 110 further includes a conductive layer 115, which is stacked with the carbon fiber layer 113 and the glass fiber insulation layer 114, and at least a portion of the conductive layer 115 is located on the side of the glass fiber insulation layer 114 away from the cell explosion-proof valve 200.

[0052] The conductive layer 115 itself has good conductivity, which can reduce the internal impedance of the body 110 and provide a low-impedance path for electromagnetic signals. At least a portion of the conductive layer 115 is located on the side of the glass fiber insulation layer 114 away from the cell explosion-proof valve 200. Specifically, the conductive layer 115 is located on the side of the glass fiber insulation layer 114 away from the cell explosion-proof valve 200 where insulation is required in the body 110. It is covered by the glass fiber insulation layer 114, which can maintain insulation isolation from the high-voltage environment of the cell and prevent the conductive layer 115 from affecting the insulation withstand voltage performance of the upper cover structure 100. This solves the contradiction between the conductivity requirement of electromagnetic shielding and the insulation withstand voltage requirement of insulation. While ensuring that the glass fiber insulation layer 114 provides effective insulation (meeting the safety requirements of the high-voltage environment), electromagnetic shielding is achieved through the conductive layer 115.

[0053] Combination Figure 1 In some embodiments, the battery pack also includes a lower housing 300, and the cell explosion-proof valve 200 is located inside the lower housing 300.

[0054] Combination Figure 3 The main body 110 has a protective area 116 and a connecting area 117 surrounding the protective area 116. Reinforcing ribs 111 and an aerogel layer 120 are disposed in the protective area 116. The connecting area 117 can be a flange structure, used to connect to the lower housing 300. The connecting area 117 is rigidly connected to the lower housing 300 by means such as bolts or snap-fits, ensuring the overall sealing of the battery pack, preventing dust and moisture intrusion, and dispersing the stress of the battery pack under vibration conditions such as turbulence during electric aircraft flight, thus avoiding fatigue fracture at the connection point.

[0055] Combination Figure 5 , Figure 6 and Figure 7 The fiberglass insulation layer 114 at least covers the protective area 116, forming an insulation barrier in the protective area 116 to prevent high voltage, such as 500V or higher, from the cell side from being conducted to the outside of the main body 110, thus avoiding the risk of leakage. In this embodiment, the fiberglass insulation layer 114 may extend to the position where the protective area 116 meets the connection area 117, or it may extend to the connection area 117; no specific limitation is made here.

[0056] A portion of the conductive layer 115 is exposed on the side of the connection area 117 that connects to the lower housing 300. This exposed portion of the conductive layer 115 is conductive to the lower housing 300, forming a closed conductive loop, i.e., a Faraday cage, between the upper cover structure 100 and the lower housing 300. External electromagnetic interference, such as radar signals and electromagnetic radiation from motors, is guided by the conductive layer 115 to the ground of the lower housing 300 upon contact with this loop, preventing it from penetrating into the battery pack. The electromagnetic radiation from the internal battery cells is also constrained by this loop, preventing leakage and interference with avionics equipment such as navigation systems.

[0057] To achieve the stacking of the conductive layer 115 with the carbon fiber layer 113 and the glass fiber insulation layer 114, and with at least a portion of the conductive layer 115 located on the side of the glass fiber insulation layer 114 away from the cell explosion-proof valve 200, there are various arrangements between the conductive layer 115 and the carbon fiber layer 113 and the glass fiber insulation layer 114, which are described below by example.

[0058] Combination Figure 5 In one alternative embodiment, in the protective area 116, the conductive layer 115 is located between the glass fiber insulation layer 114 and the carbon fiber layer 113, and in the connection area 117, the conductive layer 115 extends to the side of the carbon fiber layer 113 near the lower housing 300.

[0059] Specifically, in the protective area 116, the conductive layer 115 is laid between the glass fiber insulation layer 114 and the carbon fiber layer 113, that is, the conductive layer 115 is located on the side of the glass fiber insulation layer 114 away from the battery cell, and is stacked with the glass fiber insulation layer 114 and the carbon fiber layer 113. In the connection area 117, the conductive layer 115 extends from the laying position in the protective area 116 to the side of the carbon fiber layer 113 near the lower housing 300, and is not covered by the glass fiber insulation layer 114, but is exposed on the surface of the connection area 117 that is in contact with the lower housing 300, thus achieving conductivity with the lower housing 300.

[0060] Combination Figure 6 In another alternative embodiment, in the protective zone 116, the conductive layer 115 is located between two adjacent carbon fiber layers 113. That is, within the protective zone 116, the conductive layer 115 has carbon fiber layers 113 on both the side near the cell explosion-proof valve 200 and the side away from the cell explosion-proof valve 200. In the connection zone 117, the conductive layer 115 extends to the side of the carbon fiber layer 113 near the lower housing 300 and is not covered by the glass fiber insulation layer 114. It is exposed on the surface of the connection zone 117 that contacts the lower housing 300, thus achieving conductivity with the lower housing 300.

[0061] Of the two options mentioned above, in the first option, the conductive layer 115 is close to the glass fiber insulating layer 114, which can reduce the impact on the overall mechanical properties of the multiple carbon fiber layers 113; in the second option, the conductive layer 115 is embedded between the carbon fiber layers 113, which is more suitable for complex layup designs.

[0062] In the two optional methods described above, since both the connection area 117 and the protective area 116 of the main body 110 have a carbon fiber layer 113 and a conductive layer 115, while the glass fiber insulation layer 114 does not cover all or part of the connection area 117, the overall thickness of the part of the connection area 117 not covered by the glass fiber insulation layer 114 is easily less than the thickness of other parts of the main body 110. Consequently, the conductive layer 115 may not be able to make good contact with the lower housing 300. Therefore, this embodiment makes the following improvements:

[0063] A portion of the multiple carbon fiber layers 113 are located in the connection region 117 and the protective region 116, while another portion of the carbon fiber layers 113 are located in the connection region 117, such that the total thickness of the carbon fiber layers 113 in at least a portion of the body 110 in the connection region 117 is greater than the total thickness of the carbon fiber layers 113 in the protective region 116.

[0064] The total thickness of the aforementioned carbon fiber layer 113 refers to the sum of the thicknesses of the plurality of carbon fiber layers 113 stacked at that location. For example, the number of carbon fiber layers 113 at at least a portion of the connection region 117 is greater than the number of carbon fiber layers 113 at other locations. For instance, if the glass fiber insulation layer 114 is located in the working area and extends to the connection region 117, the number of carbon fiber layers 113 in the locations of the connection region 117 not covered by the glass fiber insulation layer 114 is greater than the number of carbon fiber layers 113 in both the connection region 117 and the working area covered by the glass fiber insulation layer 114. This results in the total thickness of the carbon fiber layers 113 in the locations of the connection region 117 not covered by the glass fiber insulation layer 114 being greater than the total thickness of the carbon fiber layers 113 in both the connection region 117 and the working area covered by the glass fiber insulation layer 114. In this way, the conductive layer 115 exposed on the side of the connection area 117 that is in contact with the lower housing 300 can be closer to the lower housing 300, which helps to ensure the conductivity between the conductive layer 115 and the lower housing 300.

[0065] Optionally, the total thickness of the carbon fiber layer 113 and the conductive layer 115 in at least a portion of the connection area 117 not covered by the glass fiber insulation layer 114 is greater than or equal to the total thickness of the conductive layer 115 at the overlapping position of the carbon fiber layer 113 and the glass fiber insulation layer 114, thereby ensuring that the conductive layer 115 can conduct electricity with the lower housing 300 when the upper cover structure 100 is connected to the lower housing 300.

[0066] Combination Figure 7In another alternative, the conductive layer 115 covers the side of the body 110 away from the cell explosion-proof valve 200, and the conductive layer 115 extends from the edge of the body 110 to the side of the connection area 117 that is connected to the lower housing 300.

[0067] In other words, in the protective area 116, the conductive layer 115 is laid on the side of the main body 110 away from the cell explosion-proof valve 200, that is, the uppermost layer of multiple carbon fiber layers 113, and the conductive layer 115 is tightly attached to the carbon fiber layer 113 below it; in the connecting area 117, the conductive layer 115 extends from the uppermost position of the protective area 116 to the edge, folds down along the outside of the carbon fiber layer 113 of the connecting area 117, and covers the carbon fiber layer 113 of the connecting area 117, so that part of the conductive layer 115 is exposed on the side of the connecting area 117 that is connected to the lower housing 300, so as to achieve direct conduction with the lower housing 300.

[0068] The conductive layer 115 is laid on the side of the main body 110 away from the cell explosion-proof valve 200, and extends only to the side of the connection area 117 that connects with the lower housing 300. It does not come into contact with the high-voltage environment of the protection area 116 near the cell. The glass fiber insulation layer 114 can fully exert its insulation function, effectively blocking the high voltage on the cell side and ensuring the overall insulation and withstand voltage performance. The conductive layer 115 is stacked with the carbon fiber layer 113 and the glass fiber insulation layer 114, and is combined with the main body 110 by extending the edge to cover the connection area 117. This does not damage the original layup structure of the carbon fiber layer 113, has little impact on the overall mechanical strength of the upper cover structure 100, and enhances the structural integrity of the connection area 117. In addition, the laying and covering of the conductive layer 115 is compatible with the carbon fiber molding process, requiring no complex secondary processing, which is convenient for mass production. It also has high adaptability to the shape of the connection area 117. Even if the edge design is complex, stable conduction with the lower housing 300 can be achieved by extending the covering.

[0069] It is worth noting that the stacked structure of the conductive layer 115 with the carbon fiber layer 113 and the glass fiber insulating layer 114 is not limited to the above-mentioned options, and will not be described in detail here.

[0070] In some embodiments, the conductive layer 115 comprises a metal mesh or nickel-plated carbon fiber.

[0071] Metal mesh (such as copper mesh) is lightweight and flexible, and can be tightly bonded to carbon fiber layer 113 and glass fiber insulation layer 114. When layered, it will not damage the original layer structure and is compatible with composite molding process.

[0072] Nickel-plated carbon fiber itself is a carbon fiber substrate, and its material is similar to that of the carbon fiber layer 113 on the top cover. When laying up, it can reduce interlayer interface stress, improve the stability of the overall structure, and avoid the risk of delamination caused by material differences.

[0073] Both the metal mesh and the nickel-plated carbon fiber have good electrical conductivity, which can effectively reduce the internal impedance of the upper cover body 110, provide a low-resistance conduction path for electromagnetic signals, and ensure that a complete Faraday cage can be constructed after being connected with the lower box 300, thus meeting the high requirements of the aerospace field for electromagnetic shielding.

[0074] In some embodiments, the conductive layer 115 is provided with a fusible conductive node. The fusible conductive node is made of a low-melting-point alloy, such as a tin-bismuth alloy, with a melting point of 138°C. When the battery pack is working normally, the fusible conductive node is conductive, ensuring the integrity of the Faraday cage. When thermal runaway of the battery cell causes the local temperature to exceed a threshold, for example, when the temperature reaches 150°C, the fusible conductive node melts, disconnecting the local conductive layer 115 and preventing the glass fiber insulation layer 114 from being damaged at high temperatures, thus avoiding a short circuit, the conductive layer 115 forms an electric spark with the lower housing 300.

[0075] Combination Figure 1 This application also provides a battery pack, including a lower housing 300, a cell explosion-proof valve 200, and an upper cover structure 100 of any of the above embodiments, wherein the cell explosion-proof valve 200 is located inside the lower housing 300, and the upper cover structure 100 is connected to the lower housing 300.

[0076] For example, the lower housing 300 serves as the basic load-bearing structure of the battery pack, housing the battery cells and the battery cell explosion-proof valve 200. Its edge is provided with a connecting part 310 that matches the connecting area 117 of the upper cover structure 100. The upper cover structure 100 and the lower housing 300 are connected by the cooperation of the connecting area 117 and the connecting part 310. The connection method includes bolt connection, snap-fit, or adhesive. The protective area 116 of the upper cover structure 100 corresponds to the position of the battery cells and the battery cell explosion-proof valve 200 in the lower housing 300. The protective area 116 is provided with reinforcing ribs 111, an aerogel layer 120, a glass fiber insulation layer 114, and a conductive layer 115. The specific structure can be referred to the foregoing description.

[0077] When a battery cell experiences thermal runaway, the cell explosion-proof valve 200 inside the lower housing 300 opens to release a high-temperature jet. The aerogel layer 120 in the protective area 116 of the upper cover structure 100 resists the high-temperature impact, preventing the upper cover structure 100 from burning through or deforming. The glass fiber insulation layer 114 blocks the high voltage on the cell side, preventing leakage. The exposed conductive layer 115 of the connection area 117 of the upper cover structure 100 is connected to the lower housing 300, forming a complete Faraday cage between the upper cover structure 100 and the lower housing 300. External electromagnetic interference such as radar signals and motor radiation in the aviation environment is guided to the lower housing 300 grounded, preventing it from entering the battery pack and interfering with the operation of the battery cells. At the same time, the electromagnetic radiation generated by the internal battery cells is confined within the Faraday cage, preventing leakage and impact on avionics equipment such as navigation systems.

[0078] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0079] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims

1. A top cover structure, characterized in that, Applied to a battery pack, the battery pack including a cell explosion-proof valve, the upper cover structure including: The body has a reinforcing rib that corresponds to the cell explosion-proof valve and protrudes in a direction away from the cell explosion-proof valve. The body has a groove formed on the side of the reinforcing rib near the cell explosion-proof valve. An aerogel layer is fixedly disposed within the groove.

2. The upper cover structure according to claim 1, characterized in that, The body includes: Multiple carbon fiber layers stacked together; A glass fiber insulation layer is stacked with the carbon fiber layer and is located on the side of the carbon fiber layer closer to the cell explosion-proof valve.

3. The upper cover structure according to claim 2, characterized in that, The body also includes: A conductive layer is stacked with the carbon fiber layer and the glass fiber insulation layer, and at least a portion of the conductive layer is located on the side of the glass fiber insulation layer opposite to the cell explosion-proof valve.

4. The upper cover structure according to claim 3, characterized in that, The battery pack also includes a lower housing, and the cell explosion-proof valve is located inside the lower housing; The main body has a protective area and a connection area surrounding the outside of the protective area. The connection area is used to connect with the lower housing. The glass fiber insulation layer at least covers the protective area, and a portion of the conductive layer is exposed on the side of the connection area that connects with the lower housing.

5. The upper cover structure according to claim 4, characterized in that, In the protected area, the conductive layer is located between the glass fiber insulation layer and the carbon fiber layer, or the conductive layer is located between two adjacent carbon fiber layers; In the connection area, the conductive layer extends to the side of the carbon fiber layer near the lower housing.

6. The upper cover structure according to claim 5, characterized in that, A portion of the carbon fiber layers are located in the connection region and the protective region, while another portion of the carbon fiber layers are located in the connection region, such that the total thickness of the carbon fiber layers in at least a portion of the body in the connection region is greater than the total thickness of the carbon fiber layers in the protective region.

7. The upper cover structure according to claim 4, characterized in that, The conductive layer covers the side of the body away from the cell explosion-proof valve, and the conductive layer extends from the edge of the body to the side where the connection area connects with the lower housing.

8. The cover structure according to any one of claims 3 to 7, characterized in that, The conductive layer comprises a metal mesh or nickel-plated carbon fiber.

9. The cover structure according to any one of claims 2 to 7, characterized in that, The thickness of the glass fiber insulation layer is greater than or equal to 0.1 mm and less than or equal to 0.4 mm.

10. A battery pack, characterized in that, include: lower box; The cell explosion-proof valve is located inside the lower housing; as well as The upper cover structure as described in any one of claims 1 to 9, wherein the upper cover structure is connected to the lower housing.

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