Bottom protection plate, battery pack and electric equipment

Abstract

The utility model provides a bottom protection plate, a battery pack and electric equipment. The bottom protection plate comprises a protection outer layer, an anti-impact layer and an energy absorption layer, the protective outer layer comprises a first fiber-reinforced composite layer and a second fiber-reinforced composite layer which are arranged at an interval, the impact-resistant layer is arranged between the first fiber-reinforced composite layer and the second fiber-reinforced composite layer, and the energy-absorbing layer is clamped between the first fiber-reinforced composite layer and the impact-resistant layer. According to the bottom protection plate provided by the utility model, the technical problem that external impact force is easily transmitted to the battery cells in the battery pack through the bottom protection plate can be solved.

Description

Technical Field

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

[0002] In the prior art, a battery pack is equipped with a bottom guard plate. This plate protects the battery cells inside the pack from being hit by foreign objects, preventing damage to the pack and potentially causing safety accidents. However, current bottom guard plates have weak impact resistance, and impact forces can easily be transmitted through the plate to the cells inside the pack, causing damage. Utility Model Content

[0003] The embodiments of the present utility model provide a bottom guard plate, a battery pack and an electrical device, which can improve the technical problem that external impact force is easily transmitted to the battery cells in the battery pack through the bottom guard plate.

[0004] In a first aspect, embodiments of the present invention provide a bottom guard plate, comprising a protective outer layer, an impact-resistant layer, and an energy-absorbing layer. The protective outer layer comprises a first fiber-reinforced composite layer and a second fiber-reinforced composite layer spaced apart from each other, the impact-resistant layer being disposed between the first fiber-reinforced composite layer and the second fiber-reinforced composite layer, and the energy-absorbing layer being sandwiched between the first fiber-reinforced composite layer and the impact-resistant layer.

[0005] In one embodiment, the energy absorbing layer is made of any one or more of balsa wood, high-density polyurethane foam, porous metal energy absorbing material, and polymer material.

[0006] In one embodiment, a drainage groove is provided on the surface of the energy absorbing layer facing the impact resistant layer. The drainage groove extends to the outer peripheral surface of the energy absorbing layer and is used to allow resin to flow between the energy absorbing layer and the impact resistant layer.

[0007] In one embodiment, a plurality of drainage grooves are provided, and the plurality of drainage grooves are interconnected in an interlaced manner.

[0008] In one embodiment, the energy absorbing layer is in the shape of a rectangular plate and has a length direction and a width direction, and the drainage groove includes a plurality of first drainage grooves and a plurality of second drainage grooves; the first drainage grooves extend along the length direction of the energy absorbing layer, and the plurality of first drainage grooves are arranged at intervals along the width direction of the energy absorbing layer; the second drainage grooves extend along the width direction of the energy absorbing layer, and the plurality of second drainage grooves are arranged at intervals along the length direction of the energy absorbing layer.

[0009] In one embodiment, the plurality of first drainage grooves are evenly spaced along the width direction of the energy absorbing layer, and / or the plurality of second drainage grooves are evenly spaced along the length direction of the energy absorbing layer.

[0010] In an embodiment, the cross section of the drainage groove is a non-closed polygon with one side open, or the cross section of the drainage groove is an arc with an arc angle less than 360 degrees.

[0011] In an embodiment, the cross section of the drainage groove is a V shape.

[0012] In an embodiment, the thickness of the energy absorption layer is not less than 5 mm and not more than 10 mm.

[0013] In an embodiment, the impact resistance layer is made of a metal material, and the yield strength of the impact resistance layer is not less than 1200 MPa, and / or the thickness of the impact resistance layer is not less than 1 mm and not more than 2 mm.

[0014] In an embodiment, the thickness of the first fiber reinforced composite layer and the second fiber reinforced composite layer is not less than 0.6 mm and not more than 2 mm.

[0015] In an embodiment, the protective outer layer, the impact resistance layer and the energy absorption layer are compounded into the bottom guard plate through a resin transfer molding process.

[0016] In a second aspect, embodiments of the utility model provide a battery pack, the battery pack includes the bottom guard plate described in any one of the above embodiments.

[0017] In a third aspect, embodiments of the utility model provide a power consumption equipment, the power consumption equipment includes the battery pack.

[0018] The beneficial effects of embodiments of the utility model are as follows:

[0019] In embodiments of the utility model, by making the bottom guard plate include a protective outer layer, an impact resistance layer and an energy absorption layer, the protective outer layer includes a first fiber reinforced composite layer and a second fiber reinforced composite layer, and the impact resistance layer and the energy absorption layer are arranged between the first fiber reinforced composite layer and the second fiber reinforced composite layer, so that the bottom guard plate can have insulation, wear resistance and puncture resistance, and the impact resistance layer and the energy absorption layer can be protected, and the impact resistance layer and the energy absorption layer can be prevented from being corroded. The impact resistance layer can resist external impact force and disperse the external impact force concentrated at a position to different positions, so as to avoid foreign matters from directly piercing the bottom guard plate. The energy absorption layer can absorb the impact energy on the impact resistance layer, so as to avoid the impact resistance layer from being greatly deformed or pierced, and to avoid the impact force from being transmitted to the battery cell in the battery pack, thereby improving the protection effect on the battery cell.

[0020] Other features and advantages of the present application will be described in detail in the following specific embodiments. BRIEF DESCRIPTION OF DRAWINGS

[0021] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following will briefly introduce the drawings needed in the embodiment description. Obviously, the drawings in the following description are only some embodiments of the present application, and for those skilled in the art, other drawings can also be obtained from these drawings without any creative effort.

[0022] Figure 1 is a perspective view of the bottom guard plate provided by the embodiment of the present application;

[0023] Figure 2 is an exploded view of the structure of the bottom guard plate provided by the embodiment of the present application;

[0024] Figure 3 is a sectional view of the structure of the bottom guard plate provided by the embodiment of the present application;

[0025] Figure 4 is a structural schematic view of the energy-absorbing layer in the bottom guard plate provided by the embodiment of the present application;

[0026] Figure 5 is a sectional view of the structure of the battery pack provided by the embodiment of the present application. DETAILED DESCRIPTION

[0027] The technical solutions in the embodiments of the present application will be described clearly and completely in the following with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only some embodiments of the present application, but not all the embodiments. Based on the embodiments in the present application, all the other embodiments obtained by those skilled in the art without any creative effort are within the scope of protection of the present application. In addition, it should be understood that the specific embodiments described herein are only used to illustrate and explain the present application, and are not used to limit the present application. In the present application, the orientation words such as "upper" and "lower" generally refer to the upper and lower in the actual use or working state of the device, and specifically refer to the direction of the drawing surface in the drawings; and "inner" and "outer" refer to the contour of the device.

[0028] In order to improve the technical problem that the external impact force is easily transmitted to the battery cell in the battery pack through the bottom guard plate, according to the first aspect of the present application, as shown in Figures 1 to 3 , a bottom guard plate 100 is provided, which includes a protective outer layer 10, an impact-resistant layer 20 and an energy-absorbing layer 30. The protective outer layer 10 includes a first fiber-reinforced composite layer 11 and a second fiber-reinforced composite layer 12, the impact-resistant layer 20 is arranged between the first fiber-reinforced composite layer 11 and the second fiber-reinforced composite layer 12, and the energy-absorbing layer 30 is arranged between the first fiber-reinforced composite layer 11 and the impact-resistant layer 20.

[0029] Specifically, in the present embodiment, the protective outer layer 10 is composed of a first fiber-reinforced composite layer 11 and a second fiber-reinforced composite layer 12, the first fiber-reinforced composite layer 11 and the second fiber-reinforced composite layer 12 are the surface layer structure of the bottom protection plate 100, and the first fiber-reinforced composite layer 11 and the second fiber-reinforced composite layer 12 are both composite materials formed by winding, molding or pultrusion of reinforcing fiber materials and matrix materials. The reinforcing fibers therein can be glass fibers, carbon fibers, aramid fibers, etc., the matrix materials can be resins, metals, ceramics, etc., the reinforcing fibers and matrix materials used by the first fiber-reinforced composite layer 11 and the second fiber-reinforced composite layer 12 can be the same or different, and the specific composition can be flexibly selected as needed.

[0030] It should be noted that the fiber-reinforced composite material has the characteristics of high strength, lightweight, corrosion resistance, etc., and when the reinforcing fibers in the fiber-reinforced composite material are glass fibers or aramid fibers and the matrix material is resin, the fiber-reinforced composite material also has good insulation. Therefore, when the first fiber-reinforced composite layer 11 and the second fiber-reinforced composite layer 12 are used as the surface layer structure of the bottom protection plate 100, not only can the bottom protection plate 100 have the effects of insulation, wear resistance and puncture resistance, but also can protect the anti-impact layer 20 and the energy-absorbing layer 30, avoiding corrosion of the anti-impact layer 20 and the energy-absorbing layer 30, thereby eliminating the need to spray an insulating coating on the surface of the bottom protection plate 100, reducing production costs.

[0031] As shown in Figure 5 When the bottom protection plate 100 is assembled to the box body 210 of the battery pack 200, the first fiber-reinforced composite layer 11 can be closer to the battery cell 220 than the second fiber-reinforced composite layer 12, i.e. the battery cell 220 can be directly placed on the first fiber-reinforced composite layer 11.

[0032] As shown in Figure 2 or Figure 3 The bottom protection plate 100 of the present application further includes an anti-impact layer 20, which has a certain strength and toughness to resist external impact force. The specific material thereof can be a metal plate with a certain strength, such as a steel plate, an alloy plate (such as titanium alloy, magnesium-aluminum alloy), etc. When the road surface through which the automobile passes has protruding stones, the stones may scratch the bottom of the battery pack 200, at which time the bottom protection plate 100 is subjected to impact force from the stones. The anti-impact layer 20 has a certain strength, so it can avoid the bottom protection plate 100 being punctured when subjected to external impact force. In addition, because the anti-impact layer 20 has a certain toughness, the anti-impact layer 20 can deform to a certain extent when subjected to external impact force, thereby dispersing the impact force to different positions.

[0033] Optionally, in an embodiment, the impact-resistant layer 20 is a steel plate, and in order to improve the impact resistance, the impact-resistant layer 20 can be made of super strong steel (such as steel of model DP1470).

[0034] As shown in Figure 2 or Figure 3 shown, the bottom guard plate 100 further includes an energy-absorbing layer 30, and the energy-absorbing layer 30 is used to absorb the impact energy on the impact-resistant layer 20, so as to avoid that the external impact force is directly transmitted to the battery cell 220 in the battery pack 200, and improve the protection effect on the battery cell 220.

[0035] In the embodiment, the energy-absorbing layer 30 can be made of any one or more of basswood, high-density polyurethane foam, metal porous energy-absorbing material (such as aluminum honeycomb and foamed aluminum), and high polymer material (such as EVA foaming material). In general, the energy-absorbing layer 30 can be made of a material having a certain deformation capacity, and when the impact force is transmitted to the energy-absorbing layer 30, the energy-absorbing layer 30 can absorb the impact energy through its own deformation, so as to avoid that the impact force is transmitted to the battery cell 220 in the battery pack 200.

[0036] As shown in Figure 3 and Figure 5 shown, in the embodiment, the energy-absorbing layer 30 is located between the first fiber-reinforced composite layer 11 and the impact-resistant layer 20, that is, the energy-absorbing layer 30 is closer to the battery cell 220 than the impact-resistant layer 20, so that the impact force on the impact-resistant layer 20 can be better prevented from being transmitted to the battery cell 220.

[0037] In summary, it can be understood that in the embodiment of the utility model, by making the bottom guard plate 100 include the protective outer layer, the impact-resistant layer 20 and the energy-absorbing layer 30, the protective outer layer includes the first fiber-reinforced composite layer 11 and the second fiber-reinforced composite layer 12, and the impact-resistant layer 20 and the energy-absorbing layer 30 are arranged between the first fiber-reinforced composite layer 11 and the second fiber-reinforced composite layer 12, so that the bottom guard plate 100 can have the effects of insulation, wear resistance and puncture resistance, and the impact-resistant layer 20 and the energy-absorbing layer 30 can be protected, so as to avoid that the impact-resistant layer 20 and the energy-absorbing layer 30 are corroded. The impact-resistant layer 20 can resist the external impact force, and disperse the external impact force concentrated at a position to different positions, so as to avoid that the foreign matter directly pierces the bottom guard plate 100. The energy-absorbing layer 30 can absorb the impact energy on the impact-resistant layer 20, so as to avoid that the impact-resistant layer 20 is greatly deformed or pierced, and avoid that the impact force is transmitted to the battery cell 220 in the battery pack 200, and improve the protection effect on the battery cell 220.

[0038] Optionally, in an embodiment, the energy-absorbing layer 30 is made of balsa wood. Specifically, balsa wood is one of the lightest woods in the world, with a weight of only 0.1 grams per cubic centimeter. The light weight of balsa wood means that it can deform more easily when impacted, thereby absorbing and dispersing impact energy. In addition, the microstructure of balsa wood is porous, and these gaps and channels can act as "buffer zones" for energy absorption and dispersion when impacted, slowing down the transmission speed of the shock wave and reducing the destructive effect of impact energy on the material. Balsa wood can also undergo elastic or plastic deformation when impacted, and these deformation processes themselves can absorb a large amount of impact energy. It should be noted that although balsa wood is lightweight, it is structurally strong and not easily completely destroyed under impact, so it can absorb energy while maintaining a certain degree of structural integrity.

[0039] Therefore, by making the energy-absorbing layer 30 from balsa wood, the present embodiment not only better absorbs the impact energy on the impact-resistant layer 20, but also makes the structure of the bottom guard plate 100 more robust and less likely to be damaged.

[0040] Optionally, in an embodiment, the protective outer layer 10, the impact-resistant layer 20, and the energy-absorbing layer 30 are combined into the bottom guard plate 100 through a resin transfer molding process. Specifically, in the present embodiment, the impact-resistant layer 20 is made of steel plate, and the energy-absorbing layer 30 is made of balsa wood, and the protective outer layer 10, the impact-resistant layer 20, and the energy-absorbing layer 30 are combined into the bottom guard plate 100 through a resin transfer molding process.

[0041] The resin transfer molding process is an advanced composite material forming technology, and its basic principle is to inject resin into a closed mold, infiltrate the reinforcing material, and solidify to form. Specifically, during molding, the protective outer layer 10, the impact-resistant layer 20, and the energy-absorbing layer 30 can be laid in the mold cavity of the mold, and then a resin injection machine can be used to inject resin glue into the mold cavity under a certain pressure. The resin fully infiltrates the fiber-reinforced material and between the layers (i.e., the protective outer layer 10, the impact-resistant layer 20, and the energy-absorbing layer 30) under the action of pressure, and solidifies under certain conditions, and finally the composite material product, i.e., the bottom guard plate 100, is obtained.

[0042] It can be understood that through the resin transfer molding process, the resin can fully infiltrate between the first fiber-reinforced composite layer 11 and the energy-absorbing layer 30, between the energy-absorbing layer 30 and the impact-resistant layer 20, and between the impact-resistant layer 20 and the second fiber-reinforced composite layer 12, thereby causing the layers within the bottom guard plate 100 to be firmly attached together, improving the structural strength and stability of the bottom guard plate 100.

[0043] It should be noted that in order to improve the composite effect of the layers within the bottom guard plate 100, a high-pressure resin transfer molding process (the injection pressure is usually between 1.0-6.0 MPa or even higher) can be used for production.

[0044] Optionally, in an embodiment, as shown in Figure 2 and Figure 3 , the surface of the energy-absorbing layer 30 facing the impact-resistant layer 20 is concave and provided with a flow guide groove 31, the flow guide groove 31 penetrates to the outer circumferential surface of the energy-absorbing layer 30, and the flow guide groove 31 is used for allowing the resin to flow between the energy-absorbing layer 30 and the impact-resistant layer 20.

[0045] Specifically, in the present embodiment, as described above, the protective outer layer 10, the impact-resistant layer 20, and the energy-absorbing layer 30 are combined into the bottom guard plate 100 through the resin transfer molding process, and in order to allow the resin to flow more fully between the energy-absorbing layer 30 and the impact-resistant layer 20, the energy-absorbing layer 30 is made of balsa wood, and the surface of the energy-absorbing layer 30 facing the impact-resistant layer 20 is concave and provided with a flow guide groove 31, the flow guide groove 31 penetrates to the outer circumferential surface of the energy-absorbing layer 30, and thus the resin can flow between the energy-absorbing layer 30 and the impact-resistant layer 20 through the flow guide groove 31, that is, the resin can flow more fully between the energy-absorbing layer 30 and the impact-resistant layer 20, which can improve the combination effect of the energy-absorbing layer 30 and the impact-resistant layer 20.

[0046] Optionally, in an embodiment, as shown in Figure 2 or Figure 4 , the flow guide groove 31 is provided with a plurality of flow guide grooves 31, and the plurality of flow guide grooves 31 are staggered and connected. It can be understood that by providing a plurality of flow guide grooves 31, more resin can be introduced between the energy-absorbing layer 30 and the impact-resistant layer 20, thereby improving the combination effect between the energy-absorbing layer 30 and the impact-resistant layer 20. By making the plurality of flow guide grooves 31 staggered and connected, the efficiency of filling the flow guide groove 31 with resin can be improved, avoiding the situation that some flow guide grooves 31 are not filled with resin after molding is completed, and a "resin grid structure" can be formed between the energy-absorbing layer 30 and the impact-resistant layer 20 after the resin solidifies, which is conducive to improving the combination effect of the energy-absorbing layer 30 and the impact-resistant layer 20.

[0047] It should be noted that the extension direction of the plurality of flow guide grooves 31 can be flexibly designed as needed, for example, optionally, in an embodiment, as shown in Figure 4 , the energy-absorbing layer 30 is a rectangular plate and has a length direction and a width direction, the flow guide groove 31 includes a plurality of first flow guide grooves 311 and a plurality of second flow guide grooves 312; the first flow guide grooves 311 extend along the length direction of the energy-absorbing layer 30, and the plurality of first flow guide grooves 311 are arranged at intervals along the width direction of the energy-absorbing layer 30; the second flow guide grooves 312 extend along the width direction of the energy-absorbing layer 30, and the plurality of second flow guide grooves 312 are arranged at intervals along the length direction of the energy-absorbing layer 30.

[0048] That is, in the embodiment, the plurality of first flow grooves 311 and the plurality of second flow grooves 312 are staggered, and any one of the first flow grooves 311 and any one of the second flow grooves 312 are vertically crossed, so that the arrangement of the plurality of flow grooves 31 is relatively simple, easy to process, and the spacing between the flow grooves 31 can be better controlled.

[0049] Further, in an embodiment, as shown in Figure 4 , the plurality of first flow grooves 311 are uniformly spaced along the width direction of the energy absorption layer 30, and / or the plurality of second flow grooves 312 are uniformly spaced along the length direction of the energy absorption layer 30, so that the resin can be more uniformly distributed between the energy absorption layer 30 and the impact resistance layer 20, and the composite strength of the energy absorption layer 30 and the impact resistance layer 20 at each position is more uniform, ensuring that the energy absorption effect of the energy absorption layer 30 at each position is more uniform.

[0050] Optionally, in an embodiment, the cross section of the flow groove 31 is a non-closed polygon with an opening on one side. Specifically, in the embodiment, the flow groove 31 can be provided with a plurality of side walls, and the plurality of side walls are sequentially connected end to end, and the first side wall and the last side wall in the connection sequence are not connected, so that the cross section of the flow groove 31 is a non-closed polygon structure with an opening on one side.

[0051] Wherein, the number of side walls of the flow groove 31 can be flexibly selected as needed, for example, optionally, in an embodiment, as shown in Figure 3 , the flow groove 31 is provided with two side walls arranged at an angle, so that the cross section of the flow groove 31 is V-shaped, which can make the structure of the flow groove 31 relatively simple and easy to process.

[0052] For another example, in other embodiments, the number of side walls of the flow groove 31 can be three, wherein two side walls are parallel to each other and spaced apart, and one side wall is connected perpendicularly between the two parallel side walls, at this time the cross section of the flow groove 31 is a square structure with an opening on one side.

[0053] Always, the number of side walls of the flow groove 31, and the size of the angle between the side walls can be flexibly selected as needed.

[0054] Or, in another embodiment, the cross section of the flow groove 31 is an arc with an arc less than 360°, specifically, the inner wall of the flow groove 31 extends in an arc shape and the arc is less than 360°, at this time the cross section of the flow groove 31 is an arc with an arc less than 360°, which can ensure that the flow groove 31 has an opening, so that the resin in the flow groove 31 can be bonded to the impact resistance layer 20.

[0055] Wherein, the cross section of the flow groove 31 can be semicircular, semi-elliptical, arc with an arc of 90°, etc.

[0056] Of course, in other embodiments, the cross-section of the drainage groove 31 may also be other shapes (such as an irregular shape), and the specific shape can be flexibly designed according to needs.

[0057] Optionally, in one embodiment, the thickness of the energy absorbing layer 30 is not less than 5 mm and not more than 10 mm. The specific thickness can be 5 mm, 5.5 mm, 6 mm, 6.5 mm, 7 mm, 7.5 mm, 8 mm, 8.5 mm, 9 mm, 9.5 mm, 10 mm, etc.

[0058] It is understood that if the thickness of the energy absorbing layer 30 is less than 5 mm, the energy absorbing effect of the energy absorbing layer 30 may be insufficient, while if the thickness of the energy absorbing layer 30 is greater than 10 mm, the thickness of the bottom guard plate 100 may be too thick. Therefore, in this embodiment, by ensuring that the thickness of the energy absorbing layer 30 is not less than 5 mm and not greater than 10 mm, the energy absorbing layer 30 can ensure a good buffering and energy absorbing effect while preventing the bottom guard plate 100 from being too thick.

[0059] It should be noted here that you can refer to Figure 3 The thickness direction of the energy absorbing layer 30 is the stacking direction of the first fiber reinforced composite layer 11 , the energy absorbing layer 30 , the impact resistant layer 20 and the second fiber reinforced composite layer 12 .

[0060] Optionally, in one embodiment, the impact-resistant layer 20 is made of a metal material, and the yield strength of the impact-resistant layer 20 is not less than 1200 MPa. Specifically, in this embodiment, the impact-resistant layer 20 is made of DP1470 ultra-high-strength steel, which has a yield strength of 1200 MPa or even higher. This can improve the impact resistance of the impact-resistant layer 20 and provide better protection.

[0061] Optionally, in one embodiment, the thickness of the impact-resistant layer 20 is not less than 1 mm and not more than 2 mm, and the specific thickness can be 1 mm, 1.1 mm, 1.2 mm, 1.3 mm, 1.4 mm, 1.5 mm, 1.6 mm, 1.7 mm, 1.8 mm, 1.9 mm, 2 mm, etc.

[0062] It is understood that if the thickness of the impact-resistant layer 20 is less than 1 mm, the impact-resistant ability of the impact-resistant layer 20 may be weak, while if the thickness of the impact-resistant layer 20 is greater than 2 mm, the weight and cost of the bottom guard plate 100 will increase. Therefore, in this embodiment, by ensuring that the thickness of the impact-resistant layer 20 is not less than 1 mm and not greater than 2 mm, it can ensure that the impact-resistant layer 20 has good impact resistance while also avoiding excessive weight and cost of the bottom guard plate 100.

[0063] Optionally, in an embodiment, the thickness of the first fiber-reinforced composite layer 11 and the second fiber-reinforced composite layer 12 is not less than 0.6 mm and not greater than 2 mm, and the specific thickness can be 0.6 mm, 0.7 mm, 0.8 mm, 0.9 mm, 1 mm, 1.1 mm, 1.2 mm, 1.3 mm, 1.4 mm, 1.5 mm, 1.6 mm, 1.7 mm, 1.8 mm, 1.9 mm, 2 mm, etc.

[0064] It can be understood that if the thickness of the first fiber-reinforced composite layer 11 and the second fiber-reinforced composite layer 12 is less than 0.6 mm, it can result in poor corrosion resistance and puncture resistance of the protective outer layer 10, and if the thickness of the first fiber-reinforced composite layer 11 and the second fiber-reinforced composite layer 12 is greater than 2 mm, it will increase the production difficulty. Therefore, by making the thickness of the first fiber-reinforced composite layer 11 and the second fiber-reinforced composite layer 12 not less than 0.6 mm and not greater than 2 mm, it can not only ensure that the protective outer layer 10 has good corrosion resistance and puncture resistance, but also facilitate the production of the first fiber-reinforced composite layer 11 and the second fiber-reinforced composite layer 12.

[0065] As shown in FIG. 1, Figure 5 The application also provides a battery pack 200, which comprises the bottom guard plate 100. The specific structure of the bottom guard plate 100 is referred to the above embodiments. Since the battery pack 200 adopts all the technical solutions of the above embodiments, the battery pack 200 at least has all the beneficial effects brought by the technical solutions of the above embodiments, which will not be repeated here.

[0066] It should be noted that, as shown in FIG. 2, Figure 5 The battery pack 200 generally comprises a box body 210 and a battery module installed in the box body 210. The battery module comprises a plurality of battery cells 220. The bottom guard plate 100 in the application can be directly used as the bottom plate structure of the box body 210, and the battery cells 220 are directly installed on the bottom guard plate 100.

[0067] Alternatively, in some other embodiments, the bottom of the box body 210 is provided with a bottom plate, and the battery cells 220 are directly installed on the bottom plate of the box body 210. The bottom guard plate 100 in the application is fixed at the bottom of the bottom plate of the box body, so as to jointly protect the bottom of the battery cells 220 with the bottom plate of the box body 210.

[0068] The application also provides an electric device comprising the above battery pack 200. Since the battery pack 200 adopts all the technical solutions of the above embodiments, the electric device at least has all the beneficial effects brought by the technical solutions of the above embodiments, which will not be repeated here.

[0069] Among them, the electric device can be a car, a ship, an industrial device, a household device, etc.

[0070] The above has carried out the detailed introduction to the embodiment of the utility model, the principle and implementation mode of the utility model have been described in this article by applying specific examples, the above embodiment explanation is only for helping understanding the method of the utility model and its core thought; simultaneously, for the technical personnel in the art, according to the thought of the utility model, there will be changes in specific implementation mode and application range, and the above is described, the content of the specification should not be understood as the limitation of the utility model.

Claims

1. A bottom guard plate, characterized in that: include: Protective outer layer, impact resistant layer and energy absorbing layer; The protective outer layer includes a first fiber reinforced composite layer and a second fiber reinforced composite layer, the impact-resistant layer is arranged between the first fiber reinforced composite layer and the second fiber reinforced composite layer, and the energy-absorbing layer is sandwiched between the first fiber reinforced composite layer and the impact-resistant layer.

2. The bottom guard plate according to claim 1, characterized in that The energy absorbing layer is made of any one or more of balsa wood, high-density polyurethane foam, porous metal energy absorbing material, and polymer material.

3. The bottom guard plate according to claim 1, characterized in that: A drainage groove is formed on the surface of the energy absorbing layer facing the impact resistant layer. The drainage groove extends to the outer peripheral surface of the energy absorbing layer and is used for allowing resin to flow between the energy absorbing layer and the impact resistant layer.

4. The bottom guard plate according to claim 3, characterized in that: There are multiple drainage grooves, and the multiple drainage grooves are interconnected.

5. The bottom guard plate according to claim 4, characterized in that: The energy absorbing layer is in the shape of a rectangular plate and has a length direction and a width direction. The drainage groove includes a plurality of first drainage grooves and a plurality of second drainage grooves. The first drainage grooves extend along the length direction of the energy absorbing layer, and the plurality of first drainage grooves are arranged at intervals along the width direction of the energy absorbing layer. The second drainage grooves extend along the width direction of the energy absorbing layer, and the plurality of second drainage grooves are arranged at intervals along the length direction of the energy absorbing layer.

6. The bottom guard plate according to claim 5, characterized in that: The plurality of first drainage grooves are evenly spaced along the width direction of the energy absorbing layer, and / or the plurality of second drainage grooves are evenly spaced along the length direction of the energy absorbing layer.

7. The bottom guard plate according to claim 3, characterized in that: The cross section of the drainage groove is a non-closed polygon with an opening on one side, or the cross section of the drainage groove is an arc with an arc angle less than 360°.

8. The bottom guard plate according to claim 3, characterized in that: The cross section of the drainage groove is V-shaped.

9. The bottom guard plate according to any one of claims 1 to 8, characterized in that: The thickness of the energy absorbing layer is not less than 5 mm and not more than 10 mm.

10. The bottom guard plate according to any one of claims 1 to 8, characterized in that: The impact-resistant layer is made of a metal material, and the yield strength of the impact-resistant layer is not less than 1200 MPa, and / or the thickness of the impact-resistant layer is not less than 1 mm and not more than 2 mm.

11. The bottom guard plate according to any one of claims 1 to 8, characterized in that: The thickness of the first fiber-reinforced composite layer and the second fiber-reinforced composite layer is not less than 0.6 mm and not more than 2 mm.

12. The bottom guard plate according to any one of claims 1 to 8, characterized in that: The protective outer layer, the impact-resistant layer and the energy-absorbing layer are compounded into the bottom guard plate through a resin transfer molding process.

13. A battery pack, characterized in that: Comprising a bottom guard plate as described in any one of claims 1-12.

14. An electrical device, characterized in that: Comprising the battery pack as claimed in claim 13.

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