A battery pack composite protection structure and vehicle

Abstract

The present invention provides a battery pack composite protection structure, comprising a battery pack and a battery protection bottom plate, wherein the battery protection bottom plate comprises an upper fiber reinforced resin layer, a metal plate, a fiber reinforced resin frame and a lower fiber reinforced resin layer; a buffer zone is formed between the battery pack and the battery protection bottom plate, and the fiber reinforced resin frame, the metal plate and the buffer zone meet the following conditions:. At the same time, the present invention also discloses a vehicle comprising the above-mentioned battery pack composite protection structure. The battery pack composite protection structure provided by the present invention controls the free deformation amount of the battery protection bottom plate to make it compatible with the height h of the buffer zone to obtain a better protection effect, while avoiding the problem of the battery protection bottom plate being ruptured by impact or the lower fiber reinforced resin layer being pulverized by impact.

Description

Technical Field

[0001] The present invention belongs to the technical field of vehicle batteries, and in particular relates to a battery pack composite protection structure and a vehicle. Background Art

[0002] With the rapid development of electric vehicles, people have higher and higher safety requirements for electric vehicles. Electric vehicles use power battery packs as their power source. In electric vehicles, the battery packs are generally located at the bottom of the vehicle's chassis and connected to the chassis by bolts. The lower surface of the battery pack is exposed, which causes the bottom of the battery pack to be easily bumped during daily driving, resulting in the failure of the box body to rupture and protection. During driving, stones from the bottom splash and wear the battery pack, shortening the service life of the battery pack. The existing method is to protect the battery by providing a protective plate at the bottom of the battery pack. However, the existing battery pack protection structure has limited protective effect. When impacted, the deformation of the bottom protective plate is large, which causes part of the impact to be transferred to the bottom tray of the battery pack, thereby causing impact on the battery. The protective plate is easily cracked and the surface layer is powdered by impact, resulting in water vapor penetration and corrosion at the bottom of the battery pack. Summary of the invention

[0003] In view of the problems that the existing bottom protection structure of the battery pack has large deformation under impact, is prone to cracking under impact and has surface powdering, the present invention provides a battery pack composite protection structure and a vehicle.

[0004] The technical solution adopted by the present invention to solve the above technical problems is as follows:

[0005] On the one hand, the present invention provides a battery pack composite protection structure, comprising a battery pack and a battery protection bottom plate, wherein the battery protection bottom plate comprises an upper fiber reinforced resin layer, a metal plate, a fiber reinforced resin frame and a lower fiber reinforced resin layer, wherein the metal plate and the fiber reinforced resin frame are located between the upper fiber reinforced resin layer and the lower fiber reinforced resin layer, wherein the fiber reinforced resin frame is a frame structure formed by connecting a plurality of frame plates end to end, wherein the metal plate is located inside the fiber reinforced resin frame, wherein the top surface of the fiber reinforced resin frame is integrally connected to the upper fiber reinforced resin layer, and the bottom surface of the fiber reinforced resin frame is integrally connected to the lower fiber reinforced resin layer; wherein the battery protection bottom plate is arranged below the battery pack, wherein a buffer zone is formed between the battery pack and the battery protection bottom plate, wherein the fiber reinforced resin frame, the metal plate and the buffer zone meet the following conditions:

[0006]

[0007] Wherein, W is the width of the frame plate, in mm;

[0008] L is the length of the metal plate, in mm;

[0009] ρ2 is the density of the metal plate, in g / cm 3 ;

[0010] d2 is the thickness of the metal plate, in mm;

[0011] d0 is the total thickness of the upper fiber reinforced resin layer, the fiber reinforced resin frame and the lower fiber reinforced resin layer, in mm;

[0012] σ0 is the tensile strength of the fiber-reinforced resin frame, in MPa;

[0013] ε0 is the elongation at break of the fiber-reinforced resin frame;

[0014] h is the height of the buffer zone, in mm.

[0015] Optionally, the fiber reinforced resin frame, the metal plate and the buffer zone meet the following conditions:

[0016]

[0017] Optionally, the width W of the frame plate is 30-200 mm.

[0018] Optionally, the length L of the metal plate is 1200-2200 mm.

[0019] Optionally, the density ρ2 of the metal plate is 2.7-8.5 g / cm 3 .

[0020] Optionally, the thickness d2 of the metal plate is 0.7-1.5 mm.

[0021] Optionally, the total thickness d0 of the upper fiber reinforced resin layer, the fiber reinforced resin frame and the lower fiber reinforced resin layer is 1.6-4.0 mm.

[0022] Optionally, the tensile strength σ0 of the fiber reinforced resin frame is 240-380 MPa.

[0023] Optionally, the elongation at break ε0 of the fiber reinforced resin frame is 2.5% to 8%.

[0024] Optionally, the height h of the buffer zone is 4 to 12 mm.

[0025] Optionally, a plurality of first mounting holes are spaced apart on the inner side of the edge of the battery protection bottom plate, and the first mounting holes sequentially pass through the upper fiber reinforced resin layer, the fiber reinforced resin frame and the lower fiber reinforced resin layer, and a plurality of second mounting holes are formed on the bottom frame of the battery pack at positions corresponding to the plurality of first mounting holes, and a connecting piece is passed between the first mounting holes and the second mounting holes.

[0026] Optionally, the upper fiber reinforced resin layer, the fiber reinforced resin frame and the lower fiber reinforced resin layer are each independently selected from a glass fiber reinforced polyamide resin part, a glass fiber reinforced polypropylene resin part, a glass fiber reinforced polyethylene resin part, a glass fiber reinforced polycarbonate resin part or a glass fiber reinforced polystyrene resin part.

[0027] Optionally, the buffer zone is filled with a buffer layer, and the buffer layer is a honeycomb material or a hard foam material.

[0028] Optionally, the metal plate is a steel plate, and a galvanized layer is provided on the outer surface of the steel plate.

[0029] On the other hand, the present invention also provides a vehicle, characterized in that it includes the battery pack composite protective structure as described above.

[0030] According to the battery protection base provided by the present invention, the upper fiber reinforced resin layer and the lower fiber reinforced resin layer are compounded on the front and back surfaces of the metal plate. On the one hand, the upper fiber reinforced resin layer and the lower fiber reinforced resin layer can improve the anti-corrosion performance of the metal plate. At the same time, the lower fiber reinforced resin layer can resist the impact of stones and the like on the bottom of the battery protection base plate, avoiding corrosion problems at the impacted parts; on the other hand, after the upper fiber reinforced resin layer and the lower fiber reinforced resin layer are compounded with the metal plate, the rigidity and strength of the metal plate are effectively improved, and the metal plate has higher impact resistance. A fiber reinforced resin frame is provided on the periphery of the metal plate as a transition piece connecting the frame position of the upper fiber reinforced resin layer and the lower fiber reinforced resin layer, which can effectively offset the influence of the thickness of the metal plate on the connection of the frame of the upper fiber reinforced resin layer and the lower fiber reinforced resin layer, ensure the strength of the frame position of the battery protection base plate, and further facilitate the frame position of the battery protection base plate as its mounting structure on the battery pack, thereby improving its impact resistance.

[0031] Furthermore, the free shape variable of the battery protection bottom plate is related to its deformation problem when it is impacted and the protective effect on the battery pack. The free shape variable of the battery protection bottom plate needs to be controlled within an appropriate range. When the free shape variable of the battery protection bottom plate is too large, the battery protection bottom plate itself has less resistance to impact energy. When it is impacted by lower energy, it will sink into the buffer zone, reducing the effective buffer space and making it difficult to disperse the impact stress better. When the free shape variable of the battery protection bottom plate is too small, the battery protection bottom plate is prone to generate excessive shear force when subjected to external impact, causing the battery protection bottom plate to rupture at the impacted position. By limiting the relationship between the width W of the frame plate, the length L of the metal plate, the density ρ2 of the metal plate, the thickness d2 of the metal plate, the total thickness d0 of the upper fiber reinforced resin layer, the fiber reinforced resin frame and the lower fiber reinforced resin layer, the tensile strength σ0 of the fiber reinforced resin frame, the elongation at break ε0 of the fiber reinforced resin frame and the height h of the buffer zone, the strength and installation stability of the battery protection base plate can be adjusted, and then the free deformation amount of the battery protection base plate can be controlled to make it match the height h of the buffer zone to obtain better protection effect, while avoiding the problem of the battery protection base plate being broken by impact or the lower fiber reinforced resin layer being powdered by impact, thereby ensuring the anti-corrosion effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 It is a structural schematic diagram of the battery pack composite protection structure provided by the present invention;

[0033] Figure 2 for Figure 1 The enlarged schematic diagram at A in the middle;

[0034] Figure 3 It is a structural schematic diagram of the battery protection bottom plate provided by the present invention;

[0035] Figure 4 It is a schematic diagram of the matching of the metal plate and the fiber-reinforced resin frame provided by the present invention;

[0036] Figure 5 is a bottom cross-sectional schematic diagram of a battery pack composite protection structure provided by an embodiment of the present invention;

[0037] Figure 6 is a bottom cross-sectional schematic diagram of a battery pack composite protection structure provided by another embodiment of the present invention;

[0038] Figure 7 It is a schematic bottom cross-sectional view of a battery pack composite protective structure provided by another embodiment of the present invention.

[0039] The reference numerals in the drawings of the specification are as follows:

[0040] 1. Battery protection bottom plate; 11. Upper fiber reinforced resin layer; 12. Metal plate; 13. Fiber reinforced resin frame; 131. Frame plate; 14. Lower fiber reinforced resin layer; 15. First mounting hole; 2. Buffer layer; 3. Battery pack; 31. Tray; 4. Buffer zone. DETAILED DESCRIPTION

[0041] In order to make the technical problems, technical solutions and beneficial effects solved by the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0042] In the description of the present invention, it should be understood that the terms "upper", "lower", "top", "bottom", "inner", "outer", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In the description of the present invention, unless otherwise specified, "plurality" means two or more.

[0043] See also Figure 1 , Figure 3 , Figure 4 and Figure 5 As shown, an embodiment of the present invention provides a battery pack composite protection structure, including a battery pack 3 and a battery protection bottom plate 1, the battery protection bottom plate 1 includes an upper fiber reinforced resin layer 11, a metal plate 12, a fiber reinforced resin frame 13 and a lower fiber reinforced resin layer 14, the metal plate 12 and the fiber reinforced resin frame 13 are located between the upper fiber reinforced resin layer 11 and the lower fiber reinforced resin layer 14, the fiber reinforced resin frame 13 is a frame structure formed by connecting a plurality of frame plates 131 end to end, the metal plate 12 is located inside the fiber reinforced resin frame 13, the top surface of the fiber reinforced resin frame 13 is integrally connected to the upper fiber reinforced resin layer 11, and the bottom surface of the fiber reinforced resin frame 13 is integrally connected to the lower fiber reinforced resin layer 14; the battery protection bottom plate 1 is arranged below the battery pack 3, a buffer zone 4 is formed between the battery pack 3 and the battery protection bottom plate 1, and the fiber reinforced resin frame 13, the metal plate 12 and the buffer zone 4 meet the following conditions:

[0044]

[0045] Wherein, W is the width of the frame plate 131, in mm;

[0046] L is the length of the metal plate 12, in mm;

[0047] ρ2 is the density of the metal plate 12, in g / cm 3 ;

[0048] d2 is the thickness of the metal plate 12, in mm;

[0049] d0 is the total thickness of the upper fiber reinforced resin layer, the fiber reinforced resin frame and the lower fiber reinforced resin layer, in mm;

[0050] σ0 is the tensile strength of the fiber reinforced resin frame 13, in MPa;

[0051] ε0 is the elongation at break of the fiber reinforced resin frame 13;

[0052] h is the height of the buffer zone 4, in mm.

[0053] The free shape variable of the battery protection base plate 1 is related to its deformation problem when it is impacted and the protective effect on the battery pack 3. The free shape variable of the battery protection base plate 1 needs to be controlled within an appropriate range. When the free shape variable of the battery protection base plate 1 is too large, the battery protection base plate 1 itself has a small resistance to impact energy. When it is impacted by a lower energy, it will be recessed toward the buffer zone 4, so that the effective buffer space is reduced and it is difficult to disperse the impact stress well. When the free shape variable of the battery protection base plate 1 is too small, the battery protection base plate 1 is prone to generate excessive shear force under the condition of external impact, resulting in rupture of the battery protection base plate 1 at the impacted position. By limiting the relationship between the width W of the frame plate 131, the length L of the metal plate 12, the density ρ2 of the metal plate 12, the thickness d2 of the metal plate 12, the total thickness d0 of the upper fiber reinforced resin layer, the fiber reinforced resin frame and the lower fiber reinforced resin layer, the tensile strength σ0 of the fiber reinforced resin frame 13, the elongation at break ε0 of the fiber reinforced resin frame 13 and the height h of the buffer zone 4, the strength and installation stability of the battery protection base plate 1 can be adjusted, and then the free shape variable of the battery protection base plate 1 can be controlled to make it match the height h of the buffer zone 4 to obtain better protection effect, while avoiding the problem of the battery protection base plate being broken by impact or the lower fiber reinforced resin layer being powdered by impact, thereby ensuring the anti-corrosion effect.

[0054] In the description of the present invention, “the height of the buffer zone 4 ” refers to the maximum spacing distance between the battery protection bottom plate 1 and the bottom surface of the battery pack 3 .

[0055] In some embodiments, the battery pack 3 includes a tray 31 and batteries disposed on the tray 31 .

[0056] In different embodiments, the buffer zone 4 may be disposed between the battery pack 3 and the battery protection base plate 11 in different ways.

[0057] like Figure 5 As shown, in one embodiment, a groove is provided inwardly on the bottom surface of the tray 31 to form the buffer zone 4 , and the battery protection bottom plate 11 is in the shape of a flat plate, and the battery protection bottom plate 11 covers the buffer zone 4 .

[0058] like Figure 6 As shown, in one embodiment, the frame position of the battery protection base plate 1 is connected to the bottom surface of the tray 31, and a groove is provided inwardly on the bottom surface of the tray 31. The battery protection base plate 1 protrudes away from the tray 31 to form the buffer zone 4 between the tray 31 and the battery protection base plate 1.

[0059] like Figure 7 As shown, in one embodiment, the frame position of the battery protection base plate 1 is connected to the bottom surface of the tray 31, the bottom surface of the tray 31 is a plane, and the battery protection base plate 1 protrudes away from the tray 31 to form the buffer zone 4 between the tray 31 and the battery protection base plate 1.

[0060] In some embodiments, the fiber reinforced resin frame 13, the metal plate 12 and the buffer zone 4 meet the following conditions:

[0061]

[0062] By associating the width W of the frame plate 131, the length L of the metal plate 12, the density ρ2 of the metal plate 12, the thickness d2 of the metal plate 12, the total thickness d0 of the upper fiber reinforced resin layer, the fiber reinforced resin frame and the lower fiber reinforced resin layer, the tensile strength σ0 of the fiber reinforced resin frame 13, the elongation at break ε0 of the fiber reinforced resin frame 13 and the height h of the buffer zone 4, it is possible to comprehensively consider the effects of the metal plate 12, the fiber reinforced resin frame 13 and the buffer zone 4 on the protective performance of the battery pack 3 to a certain extent, so as to obtain a composite protective structure for the battery pack with excellent safety performance.

[0063] In some embodiments, the width W of the frame plate 131 is 30-200 mm.

[0064] Specifically, the width W of the frame plate 131 can be 30mm, 40mm, 50mm, 60mm, 70mm, 80mm, 90mm, 100mm, 110mm, 120mm, 130mm, 140mm, 150mm, 160mm, 170mm, 180mm, 190mm or 200mm.

[0065] When the width W of the frame plate 131 is within the above range, the battery protection base plate 1 has a suitable installation area, which effectively supports and positions the metal plate 12 in the middle thereof.

[0066] In some embodiments, the length L of the metal plate 12 is 1200-2200 mm.

[0067] Specifically, the length L of the metal plate 12 may be 1200 mm, 1400 mm, 1500 mm, 1600 mm, 1700 mm, 1800 mm, 1900 mm, 2000 mm, 2100 mm or 2200 mm.

[0068] The length L of the metal plate 12 is determined according to the length of the battery pack 3 to be protected, so that the metal plate 12 can cover the bottom position of the battery pack 3 as much as possible to achieve a better protection effect.

[0069] In some embodiments, the density ρ2 of the metal plate 12 is 2.7-8.5 g / cm 3 .

[0070] Specifically, the density ρ2 of the metal plate 12 may be 2.7 g / cm 3 、3.6g / cm 3 , 4.8g / cm 3 , 5.0g / cm 3 、6.1g / cm 3 , 7.2g / cm 3 , 7.5g / cm 3 , 7.6g / cm 3 , 7.8g / cm 3 , 8.0g / cm 3 、8.1g / cm 3 、8.2g / cm 3 、8.3g / cm 3 、8.4g / cm 3 or 8.5g / cm 3 .

[0071] The density ρ2 of the metal plate 12 can be adjusted by selecting the material and specific model of the metal plate 12, and is related to the weight and mechanical strength of the metal plate 12. When the density ρ2 of the metal plate 12 is within the above range, it has better mechanical strength and is beneficial to the lightweight control of the vehicle.

[0072] In some embodiments, the thickness d2 of the metal plate 12 is 0.7-1.5 mm.

[0073] Specifically, the thickness d of the metal plate 12 may be 0.7 mm, 0.8 mm, 0.9 mm, 1.0 mm, 1.1 mm, 1.2 mm, 1.3 mm, 1.4 mm or 1.5 mm.

[0074] The thickness d2 of the metal plate 12 affects the overall mechanical strength of the battery protection bottom plate 1. When the tensile strength of the metal plate 12 is constant, as the thickness of the metal plate 12 increases, its protection strength gradually increases, but its material cost also gradually increases, and the distance from the bottom of the vehicle to the ground is reduced. When the thickness d2 of the metal plate 12 is within the above range, the overall mechanical strength of the battery protection bottom plate 1 can be guaranteed, the cost can be effectively controlled, the distance from the ground can be guaranteed, and the lightweight control of the vehicle is also facilitated.

[0075] In some embodiments, the difference between the thickness of the fiber reinforced resin frame 13 and the thickness of the metal plate 12 is less than 0.1 mm.

[0076] When the thickness difference between the fiber reinforced resin frame 13 and the metal plate 12 is less than 0.1 mm, the fiber reinforced resin frame 13 can effectively fill the peripheral space of the metal plate 12, and play the role of connecting the upper fiber reinforced resin layer 11 and the lower fiber reinforced resin layer 14, avoiding the height difference between the frame positions of the upper fiber reinforced resin layer 11 and the lower fiber reinforced resin layer 14, and ensuring the surface flatness of the battery protection base plate 1.

[0077] In some embodiments, the fiber reinforced resin frame 13 and the metal plate 12 have the same thickness.

[0078] In some embodiments, the total thickness d0 of the upper fiber reinforced resin layer, the fiber reinforced resin frame and the lower fiber reinforced resin layer is 1.6-4.0 mm.

[0079] Specifically, the total thickness d0 of the upper fiber reinforced resin layer, the fiber reinforced resin frame and the lower fiber reinforced resin layer can be 1.6mm, 1.7mm, 1.8mm, 1.9mm, 2.0mm, 2.1mm, 2.3mm, 2.5mm, 2.6mm, 2.8mm, 2.9mm, 3.0mm, 3.1mm, 3.3mm, 3.5mm, 3.6mm, 3.8mm, 3.9mm or 4.0mm.

[0080] The total thickness d0 of the upper fiber reinforced resin layer, the fiber reinforced resin frame and the lower fiber reinforced resin layer affects the mechanical strength of the battery protection base plate 1 at the frame position. When the total thickness d0 of the upper fiber reinforced resin layer, the fiber reinforced resin frame and the lower fiber reinforced resin layer increases, the mechanical strength of the battery protection base plate 1 at the frame position also gradually increases, but its material cost increases accordingly, and at the same time leads to an increase in the distance from the ground; when the total thickness d0 of the upper fiber reinforced resin layer, the fiber reinforced resin frame and the lower fiber reinforced resin layer is within the above range, it can have a better supporting and stabilizing effect while ensuring that it is as light as possible.

[0081] In some embodiments, the tensile strength σ0 of the fiber reinforced resin frame 13 is 240-380 MPa.

[0082] Specifically, the tensile strength σ0 of the fiber reinforced resin frame 13 can be independently selected from 240 MPa, 280 MPa, 290 MPa, 300 MPa, 310 MPa, 320 MPa, 330 MPa, 340 MPa, 350 MPa, 360 MPa, 370 MPa or 380 MPa.

[0083] In some embodiments, the elongation at break ε0 of the fiber reinforced resin frame 13 is 2.5% to 8%.

[0084] Specifically, the breaking elongation ε0 of the fiber reinforced resin frame 13 can be 2.5%, 2.6%, 2.8%, 2.9%, 3.0%, 3.1%, 3.2%, 3.3%, 3.4%, 3.5%, 3.6%, 3.8%, 3.9%, 4%, 4.3%, 5.4%, 6.5%, 6.6%, 7.8%, 7.9% or 8%.

[0085] The tensile strength σ0 and elongation at break ε0 of the fiber reinforced resin frame 13 can be tested by the GB / T1447-2005 fiber reinforced plastic tensile performance test method. Type I specimens are suitable for fiber reinforced thermoplastic plates. Samples are made for testing according to the Type I specimens specified in the national standard. The limiting reinforced resin frame serves as the installation position of the battery protection base plate 1 and the fixing part of the metal plate 12. The improvement of the tensile strength σ0 of the fiber reinforced resin frame 13 is beneficial to improving the deformation resistance of the fiber reinforced resin frame 13. When the tensile strength σ0 of the fiber reinforced resin frame 13 is within the above range, the installation position of the battery protection base plate 1 has a certain buffering elasticity, which is beneficial to control the deformation of the battery protection base plate 1 when it is impacted, and avoid the problems of insufficient buffering effect and rupture or delamination of the battery protection base plate 1.

[0086] In some embodiments, the height h of the buffer zone 4 is 4-12 mm.

[0087] Specifically, the height h of the buffer zone 4 may be 4 mm, 5 mm, 6 mm, 7 mm, 8 mm, 9 mm, 10 mm, 11 mm or 12 mm.

[0088] The height of the buffer zone 4 affects the vibration reduction performance of the battery pack 3 and also affects the amplitude range of the metal plate 12. When the height h of the buffer zone 4 is within the above range, on the one hand, the vibration reduction effect on the battery is improved, and on the other hand, the problem of material delamination or rivet detachment caused by excessive amplitude of the metal plate 12 is avoided.

[0089] like Figure 2 As shown, in some embodiments, a plurality of first mounting holes 15 are spaced apart on the inner side of the edge of the battery protection bottom plate 1, and the first mounting holes 15 sequentially pass through the upper fiber reinforced resin layer 11, the fiber reinforced resin frame 13 and the lower fiber reinforced resin layer 14, and a plurality of second mounting holes are opened on the bottom frame of the battery pack at positions corresponding to the plurality of first mounting holes 15, and a connecting piece is passed between the first mounting holes 15 and the second mounting holes.

[0090] The first mounting hole 15 and the second mounting hole are used for mounting and fastening the battery protection bottom plate 1 at the bottom of the battery pack 3. By arranging the first mounting hole 15 at the inner side of the edge of the battery protection bottom plate 1 and sequentially passing through the upper fiber reinforced resin layer 11, the fiber reinforced resin frame 13 and the lower fiber reinforced resin layer 14, it is possible to avoid the first mounting hole 15 passing through the metal plate 12, thereby avoiding corrosion problems caused by the metal plate 12 being exposed at the first mounting hole 15. At the same time, the fiber reinforced resin frame 13 is conducive to improving the overall thickness and tensile shear strength of the mounting position, and has sufficient mounting stability.

[0091] A plurality of first mounting holes 15 are disposed around the outer circumference of the metal plate 12 to evenly disperse the top gravity and bottom impact force exerted on the metal plate 12 .

[0092] Specifically, during installation, a connecting piece is arranged to pass through the first mounting hole 15 and the second mounting hole to fix the battery protection bottom plate 1 to the bottom of the battery pack 3, and the connecting piece is a rivet, a screw or a bolt.

[0093] In different embodiments, the resins of the upper fiber reinforced resin layer 11, the fiber reinforced resin frame 13 and the lower fiber reinforced resin layer 14 are independently selected from thermosetting and / or thermoplastic materials. Examples may include, but are not limited to, epoxy resins, phenolic plastics, phenols, cyanates, imides (e.g., polyimide, bismaleimide (BMI), polyetherimide), polypropylenes, polyesters, benzoxazines, polybenzimidazoles, polybenzothiazoles, polyamides, polyamide-imides, polysulfones, polyethersulfones, polycarbonates, polyethylene terephthalate and polyetherketones (e.g., polyetherketone (PEK), polyetheretherketone (PEEK), polyetherketoneketone (PEKK), etc.) and combinations thereof.

[0094] In different embodiments, the fibers of the upper fiber reinforced resin layer 11, the fiber reinforced resin frame 13 and the lower fiber reinforced resin layer 14 are independently selected from glass fibers, aramid fibers, carbon fibers, graphite fibers, boron fibers, aramid fibers and mixtures thereof.

[0095] The fibers of the upper fiber reinforced resin layer 11 , the fiber reinforced resin frame 13 and the lower fiber reinforced resin layer 14 may be embedded in the resin in the form of chopped fibers, chopped fibers, non-woven fabrics, unidirectional reinforced fiber substrates, woven fabrics, and the like.

[0096] In some embodiments, the upper fiber reinforced resin layer 11, the fiber reinforced resin frame 13 and the lower fiber reinforced resin layer 14 are each independently selected from glass fiber reinforced polyamide resin parts, glass fiber reinforced polypropylene resin parts, glass fiber reinforced polyethylene resin parts, glass fiber reinforced polycarbonate resin parts or glass fiber reinforced polystyrene resin parts.

[0097] In some embodiments, the buffer zone 4 is filled with a buffer layer 2, and the buffer layer 2 is a honeycomb material or a hard foam material.

[0098] Honeycomb material or hard foam material can absorb the collapse deformation space of the battery protection plate under the action of strong external impact, buffer and absorb part of the energy of the strong external impact, prevent the compression deformation of the battery protection bottom plate 1 from impacting the internal battery cells of the battery pack 3, and further protect the battery pack 3.

[0099] In some embodiments, in some embodiments, the honeycomb material is selected from PP honeycomb material or aluminum honeycomb material; the rigid foam material is selected from PU rigid foam material, PET rigid foam material, PMI rigid foam material, PVC rigid foam material, PET rigid foam material, MPP rigid foam material, PLA rigid foam material, PI rigid foam material or EPTU foam material.

[0100] In some embodiments, the metal plate 12 is selected from iron and its alloys, aluminum and its alloys, magnesium and its alloys, copper and its alloys, titanium and its alloys, or nickel and its alloys.

[0101] In some embodiments, the metal plate 12 is a steel plate, and the outer surface of the steel plate is provided with a galvanized layer, a galvanized iron alloy layer or an electrophoretic paint protective layer.

[0102] Compared with other metal materials, the steel plate used as the metal plate 12 has better tensile strength and elongation, can meet the impact resistance requirements, and is beneficial to improving the protection of the battery pack 3.

[0103] A galvanized layer, a galvanized iron alloy layer or an electrophoretic paint protective layer is arranged on the outer surface of the steel plate to improve the anti-corrosion performance of the steel plate. When the upper fiber reinforced resin layer 11 or the fiber reinforced resin layer 14 is damaged, the galvanic cell effect formed by the galvanized layer or the galvanized iron alloy layer and the steel plate causes the galvanized layer or the galvanized iron alloy layer to corrode before the steel plate, thereby protecting the steel plate. The electrophoretic paint protective layer has good adhesion and can effectively isolate the steel plate from the external environment.

[0104] Another embodiment of the present invention provides a vehicle, comprising the battery pack composite protection structure as described above.

[0105] The present invention is further described below by way of examples.

[0106] Table 1

[0107]

[0108]

[0109] Example 1

[0110] This embodiment is used to illustrate the battery pack composite protection structure disclosed in the present invention, including a battery pack, a buffer layer and a battery protection bottom plate, the battery protection bottom plate includes a metal plate, an upper fiber reinforced resin layer, a fiber reinforced resin frame and a lower fiber reinforced resin layer, the metal plate is a galvanized steel plate, the metal plate is located between the upper fiber reinforced resin layer and the lower fiber reinforced resin layer, the fiber reinforced resin frame is a frame structure formed by connecting a plurality of frame plates end to end, the metal plate is located inside the fiber reinforced resin frame, the top surface of the fiber reinforced resin frame is integrally connected to the upper fiber reinforced resin layer, and the bottom surface of the fiber reinforced resin frame is integrally connected to the lower fiber reinforced resin layer; the battery protection bottom plate is arranged below the battery pack, a buffer zone is formed between the battery pack and the battery protection bottom plate, the buffer zone is filled with the buffer layer, and the frame of the battery protection bottom plate is installed at the bottom frame position of the battery pack by rivets.

[0111] The width W of the frame plate is 200 mm, the length L of the metal plate is 1800 mm, and the density ρ2 of the metal plate is 7.9 g / cm 3 , the thickness d2 of the metal plate is 0.8 mm, the total thickness d0 of the upper fiber reinforced resin layer, the fiber reinforced resin frame and the lower fiber reinforced resin layer is 2.6 mm, the tensile strength σ0 of the fiber reinforced resin frame is 360 MPa, the elongation at break ε0 of the fiber reinforced resin frame is 5.0% and the height h of the buffer zone is 7 mm.

[0112] Embodiments 2 to 27

[0113] Examples 2 to 27 are used to illustrate the composite protection structure of the battery pack disclosed in the present invention, including most of the structures in Example 1, and the differences are as follows:

[0114] The metal plate, upper fiber reinforced resin layer, fiber reinforced resin frame, lower fiber reinforced resin layer and buffer zone height provided in Examples 2 to 27 in Table 1 were used.

[0115] Comparative Examples 1 to 3

[0116] Comparative Examples 1 to 3 are used to compare and illustrate the composite protection structure of the battery pack disclosed in the present invention, including most of the structures in Example 1, and the differences are as follows:

[0117] The metal plate, upper fiber reinforced resin layer, fiber reinforced resin frame, lower fiber reinforced resin layer and buffer zone height provided in Comparative Examples 1 to 3 in Table 1 were used.

[0118] Performance Testing

[0119] The following performance tests were performed on the composite protection structures of the battery packs provided in the above embodiments and comparative examples:

[0120] A sphere is used as an impact head to impact the battery protection bottom plate of the battery pack composite protection structure to simulate the working condition where the bottom of the vehicle is hit by a foreign object. The diameter of the sphere is 25 mm, the weight is 10 kg, the impact energy is 300 J, and the impact speed is 8.5 m / s. The center point of the battery protection bottom plate and four points around the center point are selected as impact points, and 5 impacts are performed.

[0121] Measure the dent deformation of the battery pack tray at each impact point, select the impact point with the largest dent deformation, and record it as the dent deformation of the battery pack tray; generally, the dent amount for a 300J energy impact is required to be no more than 3mm.

[0122] Use a vernier caliper to measure the diameter of the powdered area of ​​the battery protection base plate after impact. Repeat the measurement three times for a single impact point to determine the average value. Select the impact point with the largest diameter of the powdered area and record it as the diameter of the powdered area of ​​the battery protection base plate. Generally, the diameter of the powdered area is required to be no more than 10 mm.

[0123] Record whether the battery protection bottom plate is cracked after impact.

[0124] The test results obtained are entered in Table 2.

[0125] Table 2

[0126]

[0127]

[0128] It can be seen from the test results in Table 2 that the width W of the frame plate, the length L of the metal plate, the density ρ2 of the metal plate, the thickness d2 of the metal plate, the total thickness d0 of the upper fiber reinforced resin layer, the fiber reinforced resin frame and the lower fiber reinforced resin layer, the tensile strength σ0 of the fiber reinforced resin frame, the elongation at break ε0 of the fiber reinforced resin frame and the height h of the buffer zone in the composite protection structure of the battery pack have interrelated effects. When they satisfy the relationship When the composite protective structure of the battery pack is subjected to impact, the deformation amount is small, the powdering area meets the requirements and is small, and at the same time, it has good protective buffering performance.

[0129] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A battery pack composite protection structure, characterized in that: The invention comprises a battery pack and a battery protection bottom plate, wherein the battery protection bottom plate comprises an upper fiber reinforced resin layer, a metal plate, a fiber reinforced resin frame and a lower fiber reinforced resin layer, wherein the metal plate and the fiber reinforced resin frame are located between the upper fiber reinforced resin layer and the lower fiber reinforced resin layer, wherein the fiber reinforced resin frame is a frame structure formed by connecting a plurality of frame plates end to end, wherein the metal plate is located inside the fiber reinforced resin frame, wherein the top surface of the fiber reinforced resin frame is integrally connected to the upper fiber reinforced resin layer, and the bottom surface of the fiber reinforced resin frame is integrally connected to the lower fiber reinforced resin layer; the battery protection bottom plate is arranged below the battery pack, wherein a buffer zone is formed between the battery pack and the battery protection bottom plate, and wherein the fiber reinforced resin frame, the metal plate and the buffer zone meet the following conditions: Wherein, W is the width of the frame plate, in mm; L is the length of the metal plate, in mm; ρ2 is the density of the metal plate, in g / cm 3 ; d2 is the thickness of the metal plate, in mm; d0 is the total thickness of the upper fiber reinforced resin layer, the fiber reinforced resin frame and the lower fiber reinforced resin layer, in mm; σ0 is the tensile strength of the fiber-reinforced resin frame, in MPa; ε0 is the elongation at break of the fiber-reinforced resin frame; h is the height of the buffer zone, in mm; The width W of the frame plate is 30-200 mm, 240 mm or 260 mm, the length L of the metal plate is 1200-2200 mm or 2300 mm, and the density ρ2 of the metal plate is 2.7-8.5 g / cm 3 The thickness d2 of the metal plate is 0.7~1.5mm or 2mm, the total thickness d0 of the upper fiber reinforced resin layer, the fiber reinforced resin frame and the lower fiber reinforced resin layer is 1.6~4.0mm, the tensile strength σ0 of the fiber reinforced resin frame is 240~380MPa or 400MPa, the elongation at break ε0 of the fiber reinforced resin frame is 2.5%~8%, and the height h of the buffer zone is 4~12mm or 14mm.

2. The battery pack composite protection structure according to claim 1, characterized in that: The fiber reinforced resin frame, the metal plate and the buffer zone meet the following conditions: 1 3. The battery pack composite protection structure according to claim 1, characterized in that: A plurality of first mounting holes are spaced apart on the inner side of the edge of the battery protection bottom plate, and the first mounting holes sequentially pass through the upper fiber reinforced resin layer, the fiber reinforced resin frame and the lower fiber reinforced resin layer; a plurality of second mounting holes are formed at positions of the bottom frame of the battery pack corresponding to the positions of the plurality of first mounting holes, and a connecting piece is passed between the first mounting holes and the second mounting holes.

4. The battery pack composite protection structure according to claim 1, characterized in that: The upper fiber reinforced resin layer, the fiber reinforced resin frame and the lower fiber reinforced resin layer are each independently selected from glass fiber reinforced polyamide resin, glass fiber reinforced polypropylene resin, glass fiber reinforced polyethylene resin, glass fiber reinforced polycarbonate resin or glass fiber reinforced polystyrene resin.

5. The battery pack composite protection structure according to claim 1, characterized in that: The buffer zone is filled with a buffer layer, and the buffer layer is a honeycomb material or a hard foam material.

6. The battery pack composite protection structure according to claim 1, characterized in that: The metal plate is a steel plate, and the outer surface of the steel plate is provided with a galvanized layer, a galvanized iron alloy layer or an electrophoretic paint protective layer.

7. A vehicle, characterized in that: Comprising a battery pack composite protection structure as described in any one of claims 1 to 6.

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