Bottom protection plate and battery box

Abstract

The utility model relates to the technical field of batteries, and provides a bottom protection plate and a battery box. The bottom protection plate comprises an upper skin, a lower skin and an interlayer. The lower skin and the upper skin are arranged at intervals. And the interlayer is clamped between the upper skin and the lower skin. Wherein the thickness of the upper skin is greater than that of the lower skin. Therefore, the bottom protection plate of a multi-layer structure is formed based on the upper skin, the interlayer and the lower skin, so that the strength of the bottom protection plate is improved, and the impact resistance and deformation resistance of the bottom protection plate are enhanced. The thickness of the upper skin is larger than that of the lower skin, on one hand, the upper skin can better resist deformation in the thickness direction, it is ensured that the bottom protection plate can meet the use requirement, on the other hand, use of materials of the lower skin can be reduced, and the whole bottom protection plate is thinner and lighter. Therefore, the production cost is reduced while the overall strength of the bottom guard plate is ensured to reach the standard.

Description

Technical Field

[0001] The utility model relates to the technical field of batteries, in particular to a bottom guard plate and a battery box. Background Art

[0002] In the related art, the bottom guard plate of the battery pack is usually an integrated die-cast aluminum alloy plate or steel plate. This type of bottom guard plate not only has a high manufacturing cost, but also has poor impact resistance. When subjected to external impact force, the bottom guard plate is often easily deformed, which may cause damage to the internal battery cells. Utility Model Content

[0003] The embodiments of the utility model provide a bottom guard plate and a battery box, which can improve the technical problem of high cost of the bottom guard plate.

[0004] In a first aspect, an embodiment of the present utility model provides a bottom guard plate, comprising:

[0005] Upper skin;

[0006] A lower skin, spaced apart from the upper skin;

[0007] An interlayer, sandwiched between the upper skin and the lower skin;

[0008] Wherein, the thickness of the upper skin is greater than the thickness of the lower skin.

[0009] In one embodiment, the thickness of the upper skin is 2 to 3 times the thickness of the lower skin, and / or the thickness of the upper skin is 1.2 mm to 3 mm.

[0010] In one embodiment, the upper skin and the lower skin are both resin layers, and a mesh fiber structure is embedded in the resin layer.

[0011] In one embodiment, the resin layer includes one or more of a polyvinyl chloride layer, a polypropylene layer, a polyurethane layer, a polyamide layer, a polycarbonate layer, a polyethylene plastic layer and a polyphenylene ether layer, and / or the mesh fiber structure includes one or more of a glass fiber layer, a continuous aramid fiber layer, a basalt fiber layer and a carbon fiber layer.

[0012] In one embodiment, when the resin layer is provided in a plurality of types, the plurality of resin layers are stacked; and / or, when the mesh fiber structure is provided in a plurality of types, the plurality of mesh fiber structures are stacked.

[0013] In one embodiment, the interlayer is a steel plate, and the thickness of the interlayer is 0.8 mm to 1.2 mm.

[0014] In one embodiment, an adhesive layer is provided between the interlayer and the upper skin, and / or an adhesive layer is provided between the interlayer and the lower skin.

[0015] In one embodiment, a buffer portion is provided on a side of the upper skin away from the interlayer, wherein the number of the buffer portions is multiple and the multiple buffer portions are distributed at intervals on the upper skin.

[0016] In one embodiment, the buffer portion includes one or more of an organic silicone buffer portion, a polyurethane buffer portion, an ethylene-vinyl acetate buffer portion, a polypropylene buffer portion, and an EPDM rubber buffer portion.

[0017] In one embodiment, the thickness of the buffer portion is 5 mm to 20 mm.

[0018] In a second aspect, an embodiment of the utility model provides a battery box, which includes the aforementioned bottom guard plate.

[0019] Beneficial effects of the embodiments of the utility model:

[0020] In the embodiment of the utility model, a multi-layered bottom guard plate is formed based on an upper skin, an interlayer and a lower skin, thereby improving the strength of the bottom guard plate and enhancing its impact resistance and deformation resistance. By making the thickness of the upper skin greater than that of the lower skin, on the one hand, the upper skin can better resist deformation in the thickness direction, ensuring that the bottom guard plate can meet the use requirements, and on the other hand, the use of the lower skin material can be reduced, making the bottom guard plate thinner and lighter as a whole. In this way, while ensuring that the overall strength of the bottom guard plate meets the standard, its production cost is reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative work.

[0022] Figure 1 It is a three-dimensional schematic diagram of a bottom guard plate provided in an embodiment of the utility model;

[0023] Figure 2 It is a schematic diagram of the exploded structure of the bottom guard plate provided in the embodiment of the utility model;

[0024] Figure 3 This is one of the structural schematic diagrams of the bottom guard plate after being deformed by force provided by the embodiment of the utility model;

[0025] Figure 4This is the second structural schematic diagram of the bottom guard plate after being deformed by force provided in the embodiment of the utility model.

[0026] Reference numerals:

[0027] 10-upper skin, 20-lower skin, 30-interlayer, 40-buffer. DETAILED DESCRIPTION

[0028] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, rather than all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the utility model. In addition, it should be understood that the specific implementation methods described herein are only used to illustrate and explain the utility model, and are not used to limit the utility model. In the utility model, unless otherwise stated, the directional words used, such as "upper" and "lower", generally refer to the upper and lower parts of the device in actual use or working state, specifically the drawing direction in the accompanying drawings; while "inside" and "outside" refer to the outline of the device.

[0029] For details, please refer to Figures 1 to 4 The embodiment of the utility model provides a bottom guard plate. The bottom guard plate includes an upper skin 10, a lower skin 20 and an interlayer 30. The lower skin 20 is spaced apart from the upper skin 10. The interlayer 30 is sandwiched between the upper skin 10 and the lower skin 20. The thickness of the upper skin 10 is greater than the thickness of the lower skin 20.

[0030] In the embodiment of the utility model, a bottom guard plate with a multi-layer structure is formed based on the upper skin 10, the interlayer 30 and the lower skin 20, thereby improving the strength of the bottom guard plate and enhancing its impact resistance and deformation resistance. Since the thickness of the upper skin 10 is greater than that of the lower skin 20, on the one hand, the upper skin 10 can better resist deformation in the thickness direction, ensuring that the bottom guard plate can meet the use requirements. On the other hand, the use of the material of the lower skin 20 is reduced, making the bottom guard plate thinner and lighter as a whole. In this way, the production cost is reduced while ensuring that the overall strength of the bottom guard plate meets the standards.

[0031] It is understandable that when the bottom guard plate is subjected to an external impact force, the impact force is limited to the lower skin 20. If the lower skin 20 can resist the deformation caused by the impact force, the bottom guard plate as a whole will not be deformed by the external impact force. When the lower skin 20 is deformed due to excessive impact force, the lower skin 20 can consume part of the energy of the impact force, thereby reducing the impact force on the interlayer 30 and the upper skin 10, making the interlayer 30 and the upper skin 10 less likely to deform. Therefore, by forming a multi-layer structure of the bottom guard plate, the external impact force can be gradually attenuated, so that the deformation of the innermost upper skin 10 is smaller, and the overall bottom guard plate has a stronger ability to resist deformation, so as to prevent damage to the battery cell.

[0032] And because the thickness of the upper skin 10 is greater than that of the lower skin 20, the interlayer 30 can be located at a lower position, so that the interlayer 30 can be more quickly connected to the deformation of resisting external impact force, ensuring the effect of resisting Z-direction deformation. Based on the structural design of unequal thickness, the mechanical properties of the upper skin 10, the interlayer 30 and the lower skin 20 are fully utilized, so that it has a better protection effect than the bottom guard plate of equal thickness structure.

[0033] In some embodiments, the upper skin 10 and the lower skin 20 are both resin layers, and a mesh fiber structure is embedded in the resin layer. Embedding the mesh fiber structure in the resin layer can form a continuous fiber reinforced resin-based composite material layer. By setting the upper skin 10 and the lower skin 20 as continuous fiber reinforced resin-based composite material layers, and sandwiching an interlayer 30 between the upper skin 10 and the lower skin 20, a multi-layer structure of the bottom guard plate can be formed to enhance the energy absorption effect of the bottom guard plate. As a result, the bottom guard plate has good deformation resistance in both the horizontal direction and the thickness direction, ensuring that it has good strength, while also having wear resistance and insulation and corrosion resistance.

[0034] The composite material layer of continuous fiber reinforced resin is used as the upper skin 10 and the lower skin 20, and the density of the upper skin 10 and the lower skin 20 can reach 2150kg / m 3 (kilograms per cubic meter) and has excellent tensile strength. When the bottom guard plate is deformed due to force, the upper skin 10 and the lower skin 20 can show good anti-deformation ability in the XY direction (horizontal plane direction) and can also show good anti-deformation ability in the Z axis direction (thickness direction) to prevent the battery cell from being damaged.

[0035] It is understandable that when the bottom guard plate is deformed by external force collision, the force will be transmitted from the lower skin 20 to the upper skin 10, and the mesh fiber structure can disperse the force in the XY direction, so that the deformation in the Z direction is smaller. Since the thickness of the upper skin 10 is larger, the upper skin 10 can better resist deformation in the Z direction.

[0036] like Figure 3 and Figure 4 As shown, the bottom guard plate with a multi-layer structure formed based on the upper skin 10, the interlayer 30 and the lower skin 20 makes the bottom guard plate more in line with the impact resistance principle. When the lower skin 20 is impacted, the mesh fiber structure in the lower skin 20 can disperse the force in the XY direction, and the middle interlayer 30 has a larger force-bearing area when subjected to force. Based on the high strength and bottom toughness of the interlayer 30 itself, the force can be quickly dispersed in the XY direction, and deformation can occur in a wider area of ​​the interlayer 30, but the deformation in the Z direction is small. When the force is transmitted to the upper skin 10, the mesh fiber structure in the thickened upper skin 10 can pull the interlayer 30 to resist the Z-direction deformation of the entire bottom guard plate. As a result, the overall Z-direction deformation of the bottom guard plate is small, which can protect the internal structure of the battery pack. And because the thickness of the upper skin 10 is greater than that of the lower skin 20, the interlayer 30 can be located in a lower position, so that the interlayer 30 can be connected to the deformation of the external impact force more quickly, ensuring the effect of anti-Z-direction deformation. Based on the structural design of unequal thickness, the material mechanical properties of the upper skin 10, the interlayer 30 and the lower skin 20 are fully utilized, so that the bottom guard plate has a better protective effect than the bottom guard plate of equal thickness structure.

[0037] The multi-layer bottom guard plate formed by the upper skin 10, the interlayer 30 and the lower skin 20 is a flat plate structure, so that the bottom guard plate has no shape and no hanging points, and will not cause the vehicle to roll over and lose control when a bottom collision occurs.

[0038] In some embodiments, the resin layer includes one or more of a polyvinyl chloride layer, a polypropylene layer, a polyurethane layer, a polyamide layer, a polycarbonate layer, a polyethylene plastic layer, and a polyphenylene ether layer. Wherein, when the resin layer is provided in a plurality of types, the plurality of resin layers are stacked. And / or, the mesh fiber structure includes one or more of a glass fiber layer, a continuous aramid fiber layer, a basalt fiber layer, and a carbon fiber layer. Wherein, when the mesh fiber structure is provided in a plurality of types, the plurality of mesh fiber structures are stacked.

[0039] It is understood that the continuous fiber reinforced resin matrix composite material layer has a resin layer and a mesh fiber structure embedded in the resin layer. The mesh fiber structure is embedded in the resin layer, and the resin layer can be structurally reinforced so that the upper skin 10 and the lower skin 20 have good tensile strength.

[0040] Wherein, the reticular fiber structure includes one or more of a glass fiber layer, a continuous aramid fiber layer, a basalt fiber layer and a carbon fiber layer. The reticular fiber structures of the upper skin 10 and the lower skin 20 can be selected from the same fiber layer or a different fiber layer. When there are multiple reticular fiber structures in the upper skin 10, the multiple reticular fiber structures in the upper skin 10 can be selected from the same fiber layer or a different fiber layer, and the multiple reticular fiber structures are stacked one layer at a time. When there are multiple fiber layers in the lower skin 20, the multiple fiber layers in the lower skin 20 can be selected from the same fiber layer or a different fiber layer, and the multiple reticular fiber structures are stacked one layer at a time.

[0041] Wherein, the resin layer includes one or more of a polyvinyl chloride layer, a polypropylene layer, a polyurethane layer, a polyamide layer, a polycarbonate layer, a polyethylene plastic layer and a polyphenylene ether layer. The resin layers of the upper skin 10 and the lower skin 20 can be selected from the same resin layer or different resin layers. When there are multiple resin layers in the upper skin 10, the multiple resin layers in the upper skin 10 can be selected from the same resin layer or different resin layers, and the multiple resin layers are stacked one by one. When there are multiple resin layers in the lower skin 20, the multiple resin layers in the lower skin 20 can be selected from the same resin layer or different resin layers, and the multiple resin layers are stacked one by one.

[0042] Based on the selection of the above materials for the upper skin 10 and the lower skin 20, the upper skin 10 and the lower skin 20 can have excellent tensile strength and a density of up to 2150 kg / m 3 The upper skin 10 and the lower skin 20 have good anti-deformation ability in both the XY direction and the Z direction, and have the characteristics of wear resistance, insulation and corrosion resistance. Therefore, the upper skin 10 and the lower skin 20 are made lighter and thinner, which is conducive to the lightweight design of the bottom guard plate.

[0043] For example, when the resin layer is a polyvinyl chloride layer and the mesh fiber structure is a glass fiber layer, the glass fiber layer can be directly embedded in the polyvinyl chloride layer to form a composite material layer of continuous fiber reinforced resin as the upper skin 10 and the lower skin 20 .

[0044] For example, when the resin layer is a polyvinyl chloride layer and a polypropylene layer stacked on each other, and the mesh fiber structure is a glass fiber layer, a glass fiber layer can be embedded in both the polyvinyl chloride layer and the polypropylene layer to form a composite material layer of continuous fiber reinforced resin as the upper skin 10 and the lower skin 20. Alternatively, a glass fiber layer is embedded between the polyvinyl chloride layer and the polypropylene layer to form a composite material layer of continuous fiber reinforced resin as the upper skin 10 and the lower skin 20.

[0045] For example, when the resin layer is a polyvinyl chloride layer and the mesh fiber structure is a stacked glass fiber layer and a carbon fiber layer, the stacked glass fiber layer and the carbon fiber layer can be embedded in the polyvinyl chloride layer to form a composite material layer of continuous fiber reinforced resin as the upper skin 10 and the lower skin 20.

[0046] For example, when the resin layer is a polyvinyl chloride layer and a polypropylene layer stacked together, and the mesh fiber structure is a glass fiber layer and a carbon fiber layer stacked together, the polyvinyl chloride layer and the polypropylene layer may be embedded with a glass fiber layer and a carbon fiber layer stacked together to form a composite material layer of continuous fiber reinforced resin as the upper skin 10 and the lower skin 20. Alternatively, the glass fiber layer and the carbon fiber layer stacked together are embedded between the polyvinyl chloride layer and the polypropylene layer to form a composite material layer of continuous fiber reinforced resin as the upper skin 10 and the lower skin 20.

[0047] In some embodiments, the thickness of the upper skin 10 is 2 to 3 times the thickness of the lower skin 20 , and / or the thickness of the upper skin 10 is 1.2 mm to 3 mm.

[0048] The thickness of the upper skin 10 is set to 2 to 3 times the thickness of the lower skin 20 to ensure that the upper skin 10 has good anti-deformation ability in the Z direction. At the same time, it can prevent the upper skin 10 from being too thick, which will increase the weight and cost of the bottom guard plate.

[0049] It is understandable that when the thickness of the upper skin 10 is only 1.5 times the thickness of the lower skin 20, the upper skin 10's anti-deformation ability in the Z direction cannot meet the use requirements, which will cause certain safety hazards in the battery pack. When the thickness of the upper skin 10 is 4 times the thickness of the lower skin 20, the material and weight of the upper skin 10 will be larger, which will lead to an increase in the overall weight, cost and thickness of the bottom guard plate, which is not conducive to the thin and low-cost design of the bottom guard plate.

[0050] Exemplarily, the thickness of the upper skin 10 is 1.2 mm, 1.8 mm, 2 mm, 2.4 mm, 3 mm, or any value therebetween. The thickness of the lower skin 20 is 0.4 mm, 0.6 mm, 1 mm, 1.5 mm, or any value therebetween.

[0051] In some embodiments, the interlayer 30 is a steel plate, and the thickness of the interlayer 30 is 0.8 mm to 1.2 mm.

[0052] A steel plate is used as the interlayer 30 , and the steel plate can transmit the force of the lower skin 20 in its own XY directions, thereby resisting deformation in the Z direction to a certain extent, so as to protect the battery cell.

[0053] Exemplarily, the thickness of the interlayer 30 is 0.8 mm, 1 mm, 1.2 mm, or any value therebetween. When the thickness of the interlayer 30 is less than 0.8 mm, the deformation resistance of the steel plate in the Z direction cannot meet the use requirements, which will cause certain safety hazards in the battery pack. When the thickness of the interlayer 30 is greater than 1.2 mm, the weight of the steel plate is large, which will lead to an increase in the overall weight, cost and thickness of the bottom guard plate, which is not conducive to the lightweight and low-cost design of the bottom guard plate.

[0054] For example, the interlayer 30 can be made of DP780 steel plate, DP980 steel plate, DP1180 steel plate, DP1310 steel plate, DP1470 steel plate, HC1200 / 1500MS steel plate or HC1350 / 1700MS steel plate. Thus, the tensile strength of the interlayer 30 can reach 800MPa to 1700MPa (megapascals), the yield strength can reach 800MPa to 1500MPa, and it has the advantages of low toughness, high wear resistance, high rigidity, etc. Thus, the interlayer 30 can resist puncture and Z-direction deformation very well.

[0055] It is understandable that when the lower skin 20 is impacted, the mesh fiber structure in the lower skin 20 can disperse the force in the XY direction, and the middle interlayer 30 has a larger force-bearing area when subjected to force. Based on the high strength and bottom toughness of the steel plate itself, the force can be quickly dispersed in the XY direction of the steel plate, and deformation can occur in a wider area of ​​the steel plate, so that the deformation of the steel plate in the Z direction is smaller. When the force is transmitted from the steel plate to the upper skin 10, the mesh fiber structure in the thickened upper skin 10 can pull the steel plate to resist the Z-direction deformation of the entire bottom guard plate. As a result, the overall Z-direction deformation of the bottom guard plate is smaller, which can protect the internal structure of the battery pack. And because the thickness of the upper skin 10 is greater than that of the lower skin 20, the steel plate can be located in a lower position, so that the steel plate can be more quickly connected to the deformation of the external impact force, ensuring the effect of resisting Z-direction deformation.

[0056] In some embodiments, an adhesive layer is provided between the interlayer 30 and the upper skin 10 , and / or an adhesive layer is provided between the interlayer 30 and the lower skin 20 .

[0057] Based on the fact that the interlayer 30 is a steel plate, and the upper skin 10 and the lower skin 20 are composite material layers of continuous fiber reinforced resin, and due to the good polarity and easy bonding of polymer materials, a reliable connection can be formed between the upper skin 10, the interlayer 30 and the lower skin 20 by gluing, thereby ensuring the stability of the bottom guard plate structure.

[0058] For example, when gluing the upper skin 10, the interlayer 30 and the lower skin 20, glue may be applied between the upper skin 10 and the interlayer 30, and glue may be applied between the lower skin 20 and the interlayer 30. Then, the bonding area of ​​the glue between the upper skin 10, the interlayer 30 and the lower skin 20 is increased by hot pressing, and after the bonding is completed, the glue is cured to form an adhesive layer.

[0059] For example, when gluing the upper skin 10, the interlayer 30 and the lower skin 20, a solid adhesive sheet may be placed between the upper skin 10 and the interlayer 30, and a solid adhesive sheet may be placed between the lower skin 20 and the interlayer 30. The solid adhesive sheet is then softened by hot pressing to bond the upper skin 10, the interlayer 30 and the lower skin 20, and then re-cured to form an adhesive layer after bonding.

[0060] The upper skin 10 and the lower skin 20 are connected to the upper and lower sides of the interlayer 30 by gluing and hot pressing, so that the bottom guard plate does not need to be surface treated after forming, while ensuring that the bottom guard plate has good strength and rigidity, and has the advantages of lightness and low cost.

[0061] like Figure 1 and Figure 2 As shown, in some embodiments, a buffer portion 40 is provided on the side of the upper skin 10 away from the interlayer 30. The buffer portion 40 can be used to support the battery cell, and the buffer portion 40 can play a certain buffering effect during the assembly of the battery pack and after the battery pack is installed on the vehicle. For example, when the battery pack is being assembled, the buffer portion 40 can support the tray to facilitate the welding and fixing of the tray, and play a buffering effect during the welding of the tray. When the vehicle drives on a pothole road, the buffer portion 40 can play a buffering effect on the battery cell to prevent the battery cell from being damaged.

[0062] The buffer portion 40 may be configured to be in the shape of a cylinder, a cuboid, a prism, an elliptical column, etc., as long as the buffer portion 40 can play a buffering role.

[0063] The buffer portion 40 may be bonded to the upper skin 10 by gluing.

[0064] In some embodiments, the number of buffers 40 is set to be multiple, and the multiple buffers 40 are distributed at intervals on the upper skin 10. The multiple buffers 40 can be distributed in an array or in a disorderly manner on the upper surface of the upper skin 10. For example, the number of buffers 40 is set to 24, and the 24 buffers 40 are evenly distributed on the upper surface of the upper skin 10 in a 4*6 manner. For example, the number of buffers 40 is set to 18, and the 18 buffers 40 are distributed in a disorderly manner on the upper surface of the upper skin 10.

[0065] In some embodiments, the buffer portion 40 includes one or more of an organic silicone buffer portion, a polyurethane buffer portion, an ethylene-vinyl acetate buffer portion, a polypropylene buffer portion, and an EPDM buffer portion, wherein the buffer portion 40 has a thickness of 5 mm to 20 mm.

[0066] When the number of the buffer parts 40 is set to be multiple, the materials of the multiple buffer parts 40 can be the same or different. Based on the selection of organic silicone, polyurethane, ethylene-vinyl acetate, polypropylene or EPDM rubber as the buffer part 40, the buffer part 40 can play a good shock-absorbing and buffering effect to ensure the safety of the battery pack.

[0067] Exemplarily, the thickness of the buffer portion 40 is 5 mm, 10 mm, 15 mm or 20 mm, or any value therebetween. When the thickness of the buffer portion 40 is less than 5 mm, the shock absorbing and buffering effect of the buffer portion 40 will be deteriorated, which may result in failure to protect the battery cell. When the thickness of the buffer portion 40 is greater than 20 mm, the space occupied by the buffer portion 40 in the thickness direction will be larger, which will increase the thickness of the overall battery pack structure, and is not conducive to the thin and light design of the battery pack.

[0068] Based on the bottom guard plate in the above embodiment, no mold is needed in the production stage, which can save mold costs, simplify the process flow, and reduce process costs. At the same time, the bottom guard plate is lighter, which conforms to the design concept of lightweight vehicles and is conducive to increasing the endurance of the vehicle. The multi-layer structure design of the bottom guard plate gives it good impact resistance, can disperse external forces in the XY direction, and reduce deformation in the Z direction, thereby protecting the battery pack.

[0069] On the other hand, the embodiment of the utility model further provides a battery box, which includes the bottom guard plate in the above embodiment.

[0070] In the embodiment of the utility model, a bottom guard plate with a multi-layer structure is formed based on the upper skin 10, the interlayer 30 and the lower skin 20, thereby improving the strength of the bottom guard plate and enhancing its impact resistance and deformation resistance. Since the thickness of the upper skin 10 is greater than that of the lower skin 20, on the one hand, the upper skin 10 can better resist deformation in the thickness direction, ensuring that the bottom guard plate can meet the use requirements. On the other hand, the use of the material of the lower skin 20 is reduced, making the bottom guard plate thinner and lighter as a whole. In this way, the production cost is reduced while ensuring that the overall strength of the bottom guard plate meets the standards.

[0071] The embodiments of the present invention are described in detail above. Specific examples are used in this article to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the method and core idea of ​​the present invention. At the same time, for technicians in this field, according to the idea of ​​the present invention, there will be changes in the specific implementation method and application scope. In summary, the content of this specification should not be understood as a limitation on the present invention.

Claims

1. A bottom guard plate, characterized in that: include: Upper skin; A lower skin, spaced apart from the upper skin; An interlayer, sandwiched between the upper skin and the lower skin; Wherein, the thickness of the upper skin is greater than the thickness of the lower skin.

2. The bottom guard plate according to claim 1, characterized in that: The thickness of the upper skin is 2 to 3 times the thickness of the lower skin, and / or the thickness of the upper skin is 1.2 mm to 3 mm.

3. The bottom guard plate according to claim 1, characterized in that: The upper skin and the lower skin are both resin layers, and a mesh fiber structure is embedded in the resin layer.

4. The bottom guard plate according to claim 3, characterized in that: The resin layer includes one or more of a polyvinyl chloride layer, a polypropylene layer, a polyurethane layer, a polyamide layer, a polycarbonate layer, a polyethylene plastic layer and a polyphenylene ether layer, and / or the mesh fiber structure includes one or more of a glass fiber layer, a continuous aramid fiber layer, a basalt fiber layer and a carbon fiber layer.

5. The bottom guard plate according to claim 4, characterized in that: When the resin layer is provided in a plurality of types, the plurality of resin layers are stacked; and / or when the mesh fiber structure is provided in a plurality of types, the plurality of mesh fiber structures are stacked.

6. The bottom guard plate according to any one of claims 1 to 5, characterized in that: The interlayer is a steel plate, and the thickness of the interlayer is 0.8 mm to 1.2 mm.

7. The bottom guard plate according to claim 6, characterized in that: An adhesive layer is provided between the interlayer and the upper skin, and / or an adhesive layer is provided between the interlayer and the lower skin.

8. The bottom guard plate according to any one of claims 1 to 5, characterized in that: A buffer portion is provided on a side of the upper skin away from the interlayer, wherein the number of the buffer portions is multiple and the multiple buffer portions are distributed at intervals on the upper skin.

9. The bottom guard plate according to claim 8, characterized in that: The buffer portion includes one or more of an organic silicone buffer portion, a polyurethane buffer portion, an ethylene-vinyl acetate buffer portion, a polypropylene buffer portion, and an EPDM rubber buffer portion.

10. The bottom guard plate according to claim 8, characterized in that: The thickness of the buffer portion is 5 mm to 20 mm.

11. A battery box, characterized in that: Comprising a bottom guard plate as described in any one of claims 1-10.

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