Battery pack upper cover and battery pack

Abstract

This application relates to the field of battery technology and provides a battery pack cover and a battery pack. The battery pack cover of this application includes a base layer, a first protective layer disposed on the outside of the base layer, and a second protective layer and a flame-retardant layer sequentially disposed on the inside of the base layer. The base layer is made of basalt fiber reinforced resin-based composite material or basalt fiber reinforced polypropylene composite material, and both the first and second protective layers are nano-ceramic coatings. The battery pack cover of this application not only achieves a balance between lightweight, high energy density, and high waste recycling rate, but also improves waterproof, high-temperature resistance, wear resistance, corrosion resistance, and flame-retardant properties, thereby enhancing the overall quality of the battery pack cover and the battery pack.

Description

Technical Field

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

[0002] As one of the core components of electric vehicles, the power battery pack consists of battery modules, a top cover, a lower housing, a water-cooling plate, and other parts. Traditional battery pack top covers either use metal as the base layer, which is heavy and affects the improvement of battery pack energy density, or use thermosetting plastics (such as SMC) as the base layer, which has high processing energy consumption and the waste is not recyclable. At the same time, the flame retardant performance is insufficient, and the risk of thermal runaway of the battery pack is high, which is not conducive to improving the quality of the battery pack. Utility Model Content

[0003] In view of this, this application aims to provide a battery pack cover that can improve the quality of the battery pack.

[0004] To achieve the above objectives, the technical solution of this application is implemented as follows:

[0005] A battery pack cover includes a base layer, a first protective layer disposed on the outside of the base layer, and a second protective layer and a flame-retardant layer disposed sequentially on the inside of the base layer.

[0006] The base layer is made of basalt fiber reinforced resin matrix composite material or basalt fiber reinforced polypropylene composite material, and both the first protective layer and the second protective layer are nano-ceramic coatings.

[0007] Furthermore, the flame-retardant layer is made of a phosphorus-nitrogen-based halogen-free flame retardant and / or a nano-magnesium hydroxide synergist.

[0008] Furthermore, the thickness t1 of the flame-retardant layer satisfies: 0.5≤t1≤1mm.

[0009] Furthermore, the thickness t2 of the first protective layer satisfies: 0.01≤t2≤0.05mm; and / or, the thickness t3 of the second protective layer satisfies: 0.05≤t3≤0.1mm.

[0010] Furthermore, it also includes a reinforcing layer disposed between the base layer and the second protective layer.

[0011] Furthermore, the reinforcing layer is a carbon fiber layer.

[0012] Furthermore, the thickness t4 of the reinforcing layer satisfies: 0.2≤t4≤0.4mm.

[0013] Furthermore, the basalt fiber reinforced resin matrix composite material is a chopped basalt fiber reinforced resin matrix composite material; or, the basalt fiber reinforced polypropylene composite material is a chopped basalt fiber reinforced polypropylene composite material.

[0014] Furthermore, the thickness t0 of the base layer satisfies: 1.5≤t0≤2mm.

[0015] Compared with related technologies, this application has the following advantages:

[0016] (1) The battery pack cover described in this application is made of basalt fiber reinforced resin matrix composite material or basalt fiber reinforced polypropylene composite material as the base layer. This not only solves the problem of low energy density of the battery pack caused by the heavy weight of the traditional battery pack cover using metal as the base layer, but also solves the problem of high processing energy consumption and non-recyclable waste when using thermosetting plastic as the base layer. This is conducive to achieving a balance of lightweight, high energy density and high waste recycling rate. At the same time, the first protective layer and the second protective layer are both nano-ceramic coatings, which can improve the waterproof, high temperature resistance, wear resistance and corrosion resistance of the battery pack cover, thereby improving the service life of the battery pack cover. Furthermore, the flame retardant layer can also solve the problem of insufficient flame retardant performance and reduce the risk of thermal runaway of the battery pack. This makes the battery pack cover have a better performance and thus helps to improve the quality of the battery pack.

[0017] (2) The flame retardant layer is made of phosphorus-nitrogen halogen-free flame retardant and nano magnesium hydroxide synergist, which can help improve the flame retardant performance of the battery pack cover to meet the UL94V0 flame retardant rating requirements.

[0018] (3) The thickness t1 of the flame retardant layer satisfies: 0.5≤t1≤1mm. This avoids insufficient flame retardant performance due to insufficient thickness, and excessive thickness leading to increased weight, increased cost and reduced heat dissipation performance, as well as decreased bonding strength with other layers, which can easily cause cracking and falling off. This ensures that the battery pack cover has good flame retardant performance.

[0019] (4) The thickness t2 of the first protective layer satisfies: 0.01≤t2≤0.05mm, and the thickness t3 of the second protective layer satisfies: 0.05≤t3≤0.1mm. This avoids the problem that excessive thickness can easily lead to cracking, functional failure and increased cost, while insufficient thickness can cause problems such as insufficient protection and shortened lifespan. This ensures that both the inner and outer sides of the battery pack cover have good waterproof, high temperature resistance, wear resistance and corrosion resistance properties.

[0020] (5) Setting a reinforcing layer can improve the structural strength of the battery pack cover.

[0021] (6) The reinforcing layer is a carbon fiber layer, which has good structural performance, fatigue resistance and corrosion resistance, and is also conducive to achieving lightweight.

[0022] (7) The thickness t4 of the reinforcing layer satisfies: 0.2≤t4≤0.4mm, which can avoid problems such as increased weight, stress concentration and increased cost caused by excessive thickness, while insufficient thickness will cause defects such as insufficient reinforcement, poor durability and easy to fall off.

[0023] (8) The basalt fiber reinforced resin matrix composite material is a short-cut basalt fiber reinforced resin matrix composite material, which not only inherits the weather resistance and high temperature resistance of basalt fiber itself, but is also easier to prepare and reduce costs. Furthermore, the basalt fiber reinforced polypropylene composite material is a short-cut basalt fiber reinforced polypropylene composite material, which has better processing performance and higher strength and weather resistance compared with other short-cut fiber reinforced polypropylene composite materials.

[0024] (9) The thickness t0 of the base layer satisfies: 1.5≤t0≤2mm, which can meet the structural strength requirements of the battery pack cover while taking into account weight, cost and assembly compatibility.

[0025] This application also proposes a battery pack having a battery pack cover as described above.

[0026] The battery pack described in this application has the aforementioned battery pack cover, which has the same beneficial effects as conventional technology, and will not be elaborated further here. Attached Figure Description

[0027] The accompanying drawings, which form part of this application, are used to provide a further understanding of this application. The illustrative embodiments and descriptions of this application are used to explain this application and do not constitute an undue limitation of this application. In the drawings:

[0028] Figure 1 This is a perspective view of the battery pack cover described in an embodiment of this application;

[0029] Figure 2 This is an exploded view of the internal structure of the battery pack cover described in the embodiment of this application;

[0030] Explanation of reference numerals in the attached figures:

[0031] 100. Base layer; 200. First protective layer; 300. Reinforcing layer; 400. Second protective layer; 500. Flame retardant layer;

[0032] t0, thickness of the base layer; t1, thickness of the flame-retardant layer; t2, thickness of the first protective layer; t3, thickness of the second protective layer; t4, thickness of the reinforcing layer. Detailed Implementation

[0033] To make the technical solution and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0034] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other.

[0035] Furthermore, it should be noted that in the description of this application, if terms such as "upper," "lower," "inner," or "outer" appear, indicating orientation or positional relationship, these are 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 on this application. In addition, if terms such as "first" or "second" appear, they are also used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0036] Furthermore, in the description of this application, unless otherwise expressly defined, the terms "installation," "connection," "joining," and "connector" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; 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; and they can refer to the internal connection between two components. Those skilled in the art can understand the specific meaning of the above terms in this application in light of the specific circumstances.

[0037] In this application, the terms "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to a specific feature, structure, material, or characteristic described in connection with that embodiment or example, which is included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0038] The present application will now be described in detail through exemplary embodiments. However, it should be understood that, without further description, elements, structures, and features in one embodiment may be advantageously incorporated into other embodiments.

[0039] An embodiment of the first aspect of this application provides a battery pack cover that has good structural performance, thereby improving the quality of the battery pack.

[0040] In related technologies, the power battery pack, as one of the core components of electric vehicles, consists of battery modules, a top cover, a lower shell, a water-cooling plate, and other parts. Traditional battery pack top covers either use metal as the base layer, which is heavy and affects the improvement of battery pack energy density, or use thermosetting plastics (such as SMC) as the base layer, which has high processing energy consumption and the waste is not recyclable. At the same time, the flame retardant performance is insufficient, and the risk of thermal runaway of the battery pack is high, which is not conducive to improving the quality of the battery pack.

[0041] In view of this, in order to overcome the shortcomings of the related technology, the battery pack cover of this embodiment incorporates... Figure 1 and Figure 2 As shown, the overall design includes a base layer, a first protective layer located on the outside of the base layer, and a second protective layer and a flame-retardant layer located sequentially on the inside of the base layer. The base layer is made of basalt fiber reinforced resin-based composite material or basalt fiber reinforced polypropylene composite material, and both the first and second protective layers are nano-ceramic coatings.

[0042] Therefore, using basalt fiber reinforced resin matrix composite or basalt fiber reinforced polypropylene composite for the base layer not only solves the problem of low energy density caused by the heavy weight of traditional battery pack covers using metal as the base layer, but also solves the problems of high processing energy consumption and non-recyclable waste caused by using thermosetting plastics as the base layer. This facilitates the achievement of a balance between lightweight, high energy density, and high waste recycling rate. At the same time, both the first and second protective layers are nano-ceramic coatings, which can improve the waterproof, high temperature resistance, wear resistance, and corrosion resistance of the battery pack cover, thereby extending its service life. Furthermore, the addition of a flame-retardant layer can solve the problem of insufficient flame retardant performance and reduce the risk of thermal runaway of the battery pack, thus giving the battery pack cover a better performance and improving the quality of the battery pack.

[0043] Based on the above overview, specifically, in some exemplary embodiments, the base layer uses basalt fiber reinforced resin matrix composite material, which is more suitable for scenarios with extremely high requirements for strength, high temperature resistance, and flame retardancy. Compared to basalt fiber reinforced resin matrix composite material, base layers made of basalt fiber reinforced polypropylene composite material have advantages in terms of lightweighting, cost, and processing efficiency.

[0044] When the base layer is made of basalt fiber reinforced resin matrix composite material, it can be prepared using a vacuum forming process. When the base layer is made of basalt fiber reinforced polypropylene composite material, it can be prepared using a molding process. Furthermore, both the first and second protective layers are nano-ceramic coatings, which enables the battery pack cover to achieve an IP67 (individual property protection rating) waterproof rating.

[0045] Continue to combine Figure 2As shown, in some exemplary embodiments, the flame retardant layer is made of phosphorus-nitrogen halogen-free flame retardant and nano-magnesium hydroxide synergist to improve the flame retardant performance of the battery pack cover to meet the UL94V0 flame retardant rating requirements.

[0046] Among them, UL94, the Underwriters Laboratories standard for testing the flame retardancy of plastic materials, has V0 as one of the highest flame retardancy ratings in UL94. Nano-magnesium hydroxide synergists fall under the category of nano-inorganic flame retardants. The nano-magnesium hydroxide synergist in this embodiment can be composed of materials such as layered silicates, graphite, layered dihydroxy hydroxides, and carbon nanotubes to achieve better thermal stability and flame retardancy.

[0047] Furthermore, the flame-retardant layer is made of phosphorus-nitrogen-based halogen-free flame retardants and nano-magnesium hydroxide synergists, which is existing technology. For example, Chinese patent CN115850342A discloses the co-crystallization and mixing of phosphorus-nitrogen flame retardants and magnesium hydroxide flame retardants, which can be used to improve the flame-retardant effect. Of course, in specific implementations, based on flame-retardant and cost requirements, the flame-retardant layer material can be limited to phosphorus-nitrogen-based halogen-free flame retardants or nano-magnesium hydroxide synergists.

[0048] In some exemplary embodiments, the thickness t1 of the flame-retardant layer satisfies: 0.5≤t1≤1mm, and can be specifically taken as 0.5mm, 0.75mm or 1mm, etc., to avoid insufficient flame-retardant performance due to insufficient thickness, and increased weight, increased cost and reduced heat dissipation performance due to excessive thickness, as well as reduced bonding strength with other layers, which can easily lead to cracking and falling off, thereby ensuring that the battery pack cover has good flame-retardant performance.

[0049] Continue to combine Figure 2 As shown, in some exemplary embodiments, the thickness t2 of the first protective layer satisfies: 0.01 ≤ t2 ≤ 0.05 mm, and can specifically take values ​​such as 0.01 mm, 0.03 mm, or 0.05 mm. Simultaneously, the thickness t3 of the second protective layer satisfies: 0.05 ≤ t3 ≤ 0.1 mm, and can specifically take values ​​such as 0.05 mm, 0.07 mm, or 0.1 mm. This configuration avoids the problems of excessive thickness leading to cracking, functional failure, and increased costs associated with excessively thick first and second protective layers, while insufficient thickness can cause inadequate protection and shortened lifespan. This ensures that both the inner and outer sides of the battery pack cover have good waterproof, high-temperature resistance, wear resistance, and corrosion resistance.

[0050] In addition, continue to combine Figure 2As shown, in some exemplary embodiments, a reinforcing layer is also included between the base layer and the second protective layer to improve the structural strength of the battery pack cover. Furthermore, in some exemplary embodiments, the reinforcing layer is a carbon fiber layer. The advantages of this arrangement are primarily that it provides better structural performance, fatigue resistance, and corrosion resistance, and also facilitates weight reduction.

[0051] In some exemplary embodiments, the aforementioned reinforcing layer can be used in stress concentration areas of the battery pack cover, such as rounded corners, deep cavities, and areas with thickened irregular structures. Rounded corners refer to corners or edges of the battery pack cover with rounded transitions, such as the four corners of the top surface, the junctions between the top and side walls, and the junctions between the four side walls. Deep cavities refer to hollow structural areas with a certain depth inside the battery pack cover. Thickened irregular structural areas refer to areas of the battery pack cover with irregular shapes due to installation requirements or stress characteristics. These areas require increased thickness as needed, such as bolt-locking areas and plug-in locking areas.

[0052] Furthermore, the carbon fiber layer can be made of carbon fiber prepreg, which can fully leverage the high performance advantages of carbon fiber and meet the stringent requirements for strength, lightweight, and reliability of structural components such as battery pack covers through stable material properties and flexible process adaptation.

[0053] In some exemplary embodiments, the thickness t4 of the reinforcing layer satisfies: 0.2 ≤ t4 ≤ 0.4 mm, and can specifically take values ​​such as 0.2 mm, 0.3 mm, or 0.4 mm. This avoids problems such as increased weight, stress concentration, and higher costs caused by excessively thick reinforcing layers, while insufficient thickness can lead to defects such as inadequate reinforcement, poor durability, and easy detachment.

[0054] In addition, in some exemplary embodiments, the basalt fiber reinforced resin matrix composite material is a short-cut basalt fiber reinforced resin matrix composite material, which not only inherits the weather resistance and high temperature resistance of basalt fiber itself, but is also easier to prepare and reduce costs.

[0055] Furthermore, in some exemplary embodiments, the basalt fiber reinforced polypropylene composite material is a chopped basalt fiber reinforced polypropylene composite material, which can have better processability and higher strength and weather resistance compared to other chopped fiber reinforced polypropylene composite materials.

[0056] The preferred length L of the chopped basalt fibers is 3 ≤ L ≤ 6 mm. This balances dispersion uniformity, mechanical reinforcement, and processing feasibility, fully leveraging the high strength of basalt fibers while adapting to industrialized composite material production processes. Ultimately, this meets the comprehensive requirements of "high strength, lightweight, and low cost" for components such as battery pack covers. Specifically, the content of chopped basalt fibers is preferably 20-30% to improve the impact resistance of the base layer.

[0057] Meanwhile, in some exemplary embodiments, the thickness t0 of the base layer satisfies: 1.5 ≤ t0 ≤ 2 mm, and can specifically take values ​​such as 1.5 mm, 1.8 mm, or 2 mm. The main advantage of this setting is that it can meet the structural strength requirements of the battery pack cover while balancing weight, cost, and assembly compatibility.

[0058] It is worth noting that, regarding the battery pack cover of this embodiment, based on the above exemplary embodiments, in specific implementation, as a preferred embodiment, it is still made by... Figure 1 As shown, it includes a base layer, a first protective layer disposed on the outside of the base layer, and a second protective layer and a flame-retardant layer disposed sequentially on the inside of the base layer.

[0059] The base layer is made of basalt fiber reinforced resin matrix composite material or basalt fiber reinforced polypropylene composite material, and both the first and second protective layers are nano-ceramic coatings.

[0060] The flame retardant layer is made of phosphorus-nitrogen halogen-free flame retardant and nano-magnesium hydroxide synergist.

[0061] The thickness t1 of the flame-retardant layer satisfies: 0.5≤t1≤1mm.

[0062] The thickness t2 of the first protective layer satisfies: 0.01 ≤ t2 ≤ 0.05 mm. Furthermore, the thickness t3 of the second protective layer satisfies: 0.05 ≤ t3 ≤ 0.1 mm.

[0063] This also includes a reinforcing layer located between the base layer and the second protective layer.

[0064] The reinforcing layer is a carbon fiber layer. The battery pack cover includes a top cover and a frame, a cavity formed between the top cover and the frame, and a connecting flange on the frame for connection to the lower housing of the battery pack. The reinforcing layer is located at the connecting flange, the top cover, the connection point between the top cover and the frame, or the connection point between the connecting flange and the frame.

[0065] The thickness t4 of the reinforcing layer satisfies: 0.2≤t4≤0.4mm.

[0066] Among them, the basalt fiber reinforced resin matrix composite material is a short-cut basalt fiber reinforced resin matrix composite material. Furthermore, the basalt fiber reinforced polypropylene composite material is a short-cut basalt fiber reinforced polypropylene composite material.

[0067] The thickness t0 of the base layer satisfies: 1.5≤t0≤2mm.

[0068] In the preferred embodiment of the battery pack cover above, the specific configuration and arrangement of the base layer, the first protective layer, the second protective layer, the flame retardant layer and the reinforcing layer, etc., can still be referred to the descriptions in the above exemplary embodiments. Furthermore, in this preferred embodiment, the beneficial effects brought about by the design of the base layer, the first protective layer, the second protective layer, the flame retardant layer and the reinforcing layer, etc., can also be referred to the descriptions in the above exemplary embodiments.

[0069] The battery pack cover in this embodiment, with the above design, not only solves the problem of low energy density caused by the heavy weight of traditional battery pack covers using metal as the base layer, but also solves the problems of high processing energy consumption and non-recyclable waste caused by using thermosetting plastic as the base layer. This facilitates the balance of lightweight, high energy density, and high waste recycling rate. At the same time, it can improve the waterproof, high temperature resistance, wear resistance, and corrosion resistance of the battery pack cover, thereby extending its service life. Furthermore, it can solve the problem of insufficient flame retardant performance, reducing the risk of thermal runaway of the battery pack, thus making the battery pack cover have better performance.

[0070] The second protective layer uses a nano-ceramic coating, which, in conjunction with the flame-retardant layer, further enhances the flame-retardant performance of the battery pack cover. Furthermore, the base layer is made of basalt fiber reinforced resin-based composite material or basalt fiber reinforced polypropylene composite material, shortening the molding cycle by 30% compared to traditional SMC. The basalt fiber reinforced polypropylene composite material system also boasts a waste recycling rate of ≥90%, achieving high waste recovery and preventing waste.

[0071] An embodiment of the second aspect of this application provides a battery pack having the aforementioned battery pack cover.

[0072] The battery pack in this embodiment, by setting the battery pack cover as described above, has the same beneficial effects as the conventional technology, and will not be described in detail here.

[0073] The above descriptions are merely some embodiments of this application and are not intended to limit this application. The technical features or structures in the foregoing different embodiments can be arbitrarily combined to form other specific technical solutions as needed. For those skilled in the art, this application can have various modifications and variations. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of protection of the claims of this application.

Claims

1. A battery pack cover, characterized in that: It includes a base layer, a first protective layer disposed on the outside of the base layer, and a second protective layer and a flame-retardant layer disposed sequentially on the inside of the base layer; The base layer is made of basalt fiber reinforced resin matrix composite material or basalt fiber reinforced polypropylene composite material, and both the first protective layer and the second protective layer are nano-ceramic coatings.

2. The battery pack cover according to claim 1, characterized in that: The flame-retardant layer is made of phosphorus-nitrogen-based halogen-free flame retardant and / or nano-magnesium hydroxide synergist.

3. The battery pack cover according to claim 1, characterized in that: The thickness t1 of the flame-retardant layer satisfies: 0.5≤t1≤1mm.

4. The battery pack cover according to claim 1, characterized in that: The thickness t2 of the first protective layer satisfies: 0.01 ≤ t2 ≤ 0.05 mm; and / or, The thickness t3 of the second protective layer satisfies: 0.05≤t3≤0.1mm.

5. The battery pack cover according to claim 1, characterized in that: It also includes a reinforcing layer disposed between the base layer and the second protective layer.

6. The battery pack cover according to claim 5, characterized in that: The reinforcing layer is a carbon fiber layer.

7. The battery pack cover according to claim 6, characterized in that: The thickness t4 of the reinforcing layer satisfies: 0.2≤t4≤0.4mm.

8. The battery pack cover according to claim 1, characterized in that: The basalt fiber reinforced resin matrix composite material is a short-cut basalt fiber reinforced resin matrix composite material; or... The basalt fiber reinforced polypropylene composite material is a short-cut basalt fiber reinforced polypropylene composite material.

9. The battery pack cover according to any one of claims 1 to 8, characterized in that: The thickness t0 of the base layer satisfies: 1.5≤t0≤2mm.

10. A battery pack, characterized in that: The battery pack is provided with a battery pack cover as described in any one of claims 1 to 9.

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