Integrated heating protection plate and forming method thereof

Abstract

The invention discloses an integrated heating protection plate which sequentially comprises a third composite material layer, a PP honeycomb plate layer, a steel plate layer, a second composite material layer, a heating film layer and a first composite material layer from bottom to top. And the third composite material layer and the PP honeycomb plate layer are arranged in a shape following manner. The invention further provides a forming method for preparing the integrated heating protection plate. The new energy battery pack bottom protection plate integrating the heating function, the heat preservation function and the protection function is obtained through the composite material, the structure is light, the weight of the battery pack protection plate is reduced, meanwhile, the air tightness of the battery pack is guaranteed, air holes and gaps are not prone to occurring, the hole position tolerance is reduced, and the later assembly difficulty is lowered.

Description

Technical Field

[0001] The invention relates to the technical field of protective plate manufacturing, and in particular to an integrated heating protective plate and a forming method thereof. Background Art

[0002] In the cold winter, the battery activity of new energy vehicles is low. Warming up the car can make the power battery reach a more ideal working state. Otherwise, it will have a certain impact on the cruising range. In addition, the battery needs to be preheated when charging, and charging will not start until the battery temperature reaches a certain condition.

[0003] In order to ensure that the battery of new energy vehicles reaches the appropriate temperature when starting and charging the vehicle in winter, insulation layers, protective layers, and heating layers are appropriately added to the design of the battery pack. The current solution to the temperature problem is to assemble the functional layers in the order of heating-insulation-protection, where the heating layer is closest to the battery cell and connected to the bottom of the new energy battery tray. However, the battery pack protective plate in the prior art may have the following problems:

[0004] (1) Currently, to ensure the airtightness of the battery pack, the lower tray of the battery pack and the heating layer are assembled using glue + sealing strips and mounting bolts. However, the sealing strips may age, and the glue seal may also have air holes or loosen and form gaps under vibration conditions.

[0005] (2) At present, the combined thickness of the heating layer, thermal insulation layer, and protective layer can reach 15-30 mm, which is relatively thick. At the same time, since the protective layer is mostly made of metal materials with high density, for a battery pack of 1000*1500 mm in size, the weight of the heating layer, thermal insulation layer, and protective layer can reach 30 kg, which is relatively heavy.

[0006] (3) Because the heating layer, insulation layer, and protective layer may be produced and supplied by different suppliers, it is difficult to unify the upper or lower limit of the hole tolerance, and there are many difficulties in assembly. The installation of bolts and the gluing and bonding processes have very strict operating requirements, the operation is cumbersome, and the efficiency is low.

[0007] Therefore, how to solve the problems of large thickness and weight when functional components such as insulation layer, protective layer, heating layer are designed and assembled separately, installation holes are easily offset and assembly is difficult during the assembly process, or the sealing and conductivity between layers are poor, which becomes a difficult problem that needs to be solved urgently. Summary of the invention

[0008] The object of the present invention is to provide an integrated heating protection plate and a forming method thereof, so as to solve the technical problems in the prior art of poor air tightness and difficulty in assembly between the heating layer, the thermal insulation layer and the protection layer.

[0009] In order to solve the above technical problems, the present invention specifically provides the following technical solutions:

[0010] The present invention provides an integrated heating protection plate, which comprises, from bottom to top, a third composite material layer, a PP honeycomb plate layer, a steel plate layer, a second composite material layer, a heating film layer, and a first composite material layer, wherein the PP honeycomb plate layer is provided with a sinking area capable of fitting and installing the steel plate layer, and the third composite material layer and the PP honeycomb plate layer are arranged in a conformal manner;

[0011] The third composite material layer, the second composite material layer, and the first composite material layer are all thermosetting resin-based reinforced fiber composite materials;

[0012] The second composite material layer and the first composite material layer are bonded together by thermosetting and wrap the heating film layer for fixing; the second composite material layer and the PP honeycomb plate layer are bonded together by thermosetting and wrap the steel plate layer for fixing.

[0013] As a preferred solution of the present invention, the steel plate layer is divided into a first steel plate and a second steel plate, the first steel plate and the second steel plate are respectively located on the left and right sides of the sinking area, and an intermediate assembly hole is provided between the first steel plate and the second steel plate, and the intermediate assembly hole sequentially passes through the first composite material layer, the second composite material layer, the PP honeycomb plate layer, and the third composite material layer.

[0014] The present invention also provides a method for forming an integrated heating protection plate, comprising the following steps:

[0015] Laying the third composite material plate, the PP honeycomb plate, the steel plate, the second composite material plate, the heating film, and the first composite material plate on the pre-pressed bottom plate in order from bottom to top to obtain a prefabricated part;

[0016] Rolling the preform in a flat surface with a roller, clamping the edge of the preform after rolling, and moving the preform into a mold;

[0017] Among them, after rolling, the first composite material layer, the second composite material layer and the PP honeycomb plate layer are bonded together, and the steel plate layer and the heating film layer are positioned;

[0018] The preform is hot-pressed by using a press, and the PP honeycomb panel and the third composite material panel melt and fill the pre-reserved mold cavity as the temperature rises;

[0019] The molded product is taken out of the mold and placed to cool down. After the temperature drops, it is transferred to the laser cutting process and the product is subjected to a hole-opening process to obtain the integrated heating protection plate.

[0020] As a preferred embodiment of the present invention, the plane rolling comprises the following steps:

[0021] The roller is heated to a preheating temperature, and the preform is rolled from the middle to both ends. The roller conducts heat from the first composite material layer to the third composite material layer and exhausts air in the preform.

[0022] As a preferred embodiment of the present invention, the plane rolling further comprises the following steps:

[0023] The two roller shafts of the rollers move relative to each other in the horizontal direction, rotate synchronously in opposite directions, and rotate and fit together after running to the end of the preform, performing a cycle of hot pressing action.

[0024] As a preferred solution of the present invention, the surface temperature of the roller is 60-100°C.

[0025] As a preferred embodiment of the present invention, in the hot pressing step, the mold temperature is: 130°C to 170°C;

[0026] The mold pressure selection formula is T=S*F1*F2 / F table.

[0027] As a preferred solution of the present invention, the third composite material layer is composed of two layers of 400g / ㎡ sheets, and the thickness after molding is 0.3-0.6mm.

[0028] As a preferred solution of the present invention, the second composite material layer is composed of 1-2 layers of 400g / ㎡ sheet, and the thickness after molding is 0.3-0.6mm.

[0029] As a preferred solution of the present invention, the first composite material layer is composed of two layers of 200g / ㎡ sheets, and the thickness after molding is 0.25-0.3mm.

[0030] Compared with the prior art, the present invention has the following beneficial effects:

[0031] The present invention uses composite materials to obtain a bottom protective plate for a new energy electric battery pack with heating, heat preservation and protection functions. The bottom protective plate has a light structure and a thin thickness. After the battery pack is used, the weight is light, thereby reducing the weight of the battery pack protective plate. The present invention uses multiple layers of composite materials for hot pressing, and each layer of material can be fully bonded and contacted, thereby ensuring the airtightness of the battery pack and preventing the occurrence of pores and gaps.

[0032] The present invention provides a forming method of an integrated heating protection plate, which has a simple assembly method. The hardness of the materials passed by the machine during punching is similar, so the punching operation can be performed directly, the hole position tolerance is reduced, and the difficulty of subsequent assembly is reduced. At the same time, preheating roller pressing is used to not only provide pressure to the material, but also provide a certain amount of heat, so that the steel plate and the heating film can be preliminarily connected to the composite material, reducing the probability of surface layer dislocation during subsequent punching. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] In order to more clearly illustrate the implementation methods of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for the implementation methods or the description of the prior art. Obviously, the drawings in the following description are only exemplary, and for ordinary technicians in this field, other implementation drawings can be derived from the provided drawings without creative work.

[0034] Figure 1 A schematic diagram of the structure explosion of an integrated heating protection plate is provided for the present invention;

[0035] Figure 2 The present invention provides Figure 1 A perspective structural diagram of an integrated heating protection plate in the illustrated embodiment;

[0036] Figure 3 The present invention provides Figure 1 Top view of the integrated heating protective plate in the illustrated embodiment.

[0037] Figure 4 A schematic flow chart of a molding method of an integrated heating protection plate is provided for the present invention.

[0038] The numbers in the figure represent the following:

[0039] 1-third composite material layer; 2-PP honeycomb plate layer; 3-steel plate layer; 4-second composite material layer; 5-heating film layer; 6-heating film layer; 7-assembly holes around; 8-sinking area; 9-middle assembly hole;

[0040] 301-first steel plate; 302-second steel plate. DETAILED DESCRIPTION

[0041] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0042] See also Figures 1 to 3The present invention provides an integrated heating protection plate, characterized in that it includes, from bottom to top, a third composite material layer 1, a PP honeycomb plate layer 2, a steel plate layer 3, a second composite material layer 4, a heating film layer 5, and a first composite material layer 6.

[0043] In a preferred embodiment of the present invention, the third composite material layer 1, the second composite material layer 4 and the first composite material layer 6 are all composite material plates, which are composed of thermosetting resin-based reinforced fiber composite material plates. It is recommended that the thickness of each layer can be controlled at 0.6-0.9mm. As the position of the thermosetting resin-based reinforced fiber composite material plate changes, its function changes.

[0044] In a preferred embodiment of the present invention, the third composite material layer 1 is used to fix the position of the PP honeycomb panel layer 2 to prevent the PP honeycomb panel layer 2 from moving during movement, and at the same time can protect the PP honeycomb panel layer 2, thereby playing a protective role for the PP honeycomb panel layer 2.

[0045] In a preferred embodiment of the present invention, the second composite material layer 4 is used to fix the steel plate layer 3 and the heating film layer 5. During the hot pressing process, one side of the second composite material layer 4 contacts and bonds with the PP honeycomb plate layer 2, so that the steel plate is sandwiched between the second composite material layer 4 and the PP honeycomb plate layer 2 to position the steel plate. At the same time, the second composite material layer 4 is sticky and can pre-position the steel plate before the mold is formed to prevent the steel plate from shifting before hot pressing. The other side of the second composite material layer 4 contacts and bonds with the first composite material layer 6 to position the heating film layer 5. At the same time, the second composite material layer 4 and the first composite material layer 6 are sticky and can pre-position the heating film layer 5 before the mold is formed to prevent the heating film layer 5 from shifting before hot pressing.

[0046] In a preferred embodiment of the present invention, the first composite material layer 6 is used to fix the heating film layer 5, and at the same time can protect the heating film layer 5 and position the heating film when stacked. Since the first composite material layer 6 has a certain viscosity, it can prevent its displacement before hot pressing.

[0047] In particular, in this embodiment, the heating layer is made of a polyimide film as an outer insulator and a metal foil and a metal wire as an inner conductive heating element, and is heat-sealed at high temperature and high pressure to form a PI electric heating film.

[0048] The main structure of the heating layer before hot pressing is twisted into an S shape. The filamentary structure forms a fixed structure after twisting, which plays a heating role between the second composite material layer 4 and the first composite material layer 6. The interface between the positive and negative poles is located at the edge of the entire protective plate, and can be respectively arranged between two adjacent surrounding assembly holes 7.

[0049] In the present invention, the advantage of the heating wire is that it can not only quickly provide a thermal environment for the battery, but also because there are gaps between the heating wires, parts of the first composite material layer 6 and the second composite material layer 4 can be directly bonded together during layer laying. Both the first composite material layer 6 and the second composite material layer 4 have a certain degree of viscosity, which facilitates positioning of the entire heating film, prevents displacement before hot pressing, prevents deviation of the interfaces between the positive and negative poles, and improves connection accuracy.

[0050] At the same time, after hot pressing, each position of the heating wire of the heating film layer 5 is sealed and bonded to the inside of the first composite material layer 6 and the second composite material layer 4, so it is not easy to have air holes during the subsequent cutting and punching process, or loosen and form gaps under vibration conditions. It can also prevent it from falling off during subsequent use.

[0051] In the present invention, the assembly accuracy of the heating film layer is provided by its specific shape, composition and the material properties of the first composite material layer 6 and the second composite material layer 4, which not only simplifies the difficulty of assembling the heating layer, but also reduces the probability of the heating layer shifting after laying, and can also reduce the phenomenon of air holes, vibration gaps, etc. that appear when the material layer is punched after hot pressing and during use.

[0052] In a preferred embodiment of the present invention, the honeycomb panel material can be PP material. PP material is a thermoplastic material, has good adhesion with thermosetting resin-based materials, and will not delaminate after molding. PP honeycomb panels have strong pressure resistance and impact resistance; PP honeycomb panels absorb external forces, thereby reducing the damage caused by impacts and collisions; they are lightweight and rigid, environmentally friendly, shock-absorbing, cold-resistant, sound-insulating, heat-insulating, moisture-proof and heat-insulating. Note that materials with a flame retardant level of UL94 V0 should be selected. The PP honeycomb panel layer 2 can be deformed during the hot pressing process. The PP honeycomb panel layer 2 mainly has a buffering effect, which provides buffering protection for the steel plate, heating film and the internal structure of the battery.

[0053] In particular, the PP honeycomb panel can also be deformed during the subsequent hot pressing process, providing a fitting gap for the steel plate layer 3, and reducing the pores and bonding gaps between the layers due to the presence of the protective layer and other unequal surfaces. After the material is formed, a sinking area 8 capable of fitting and installing the steel plate layer 3 is provided on the PP honeycomb panel layer 2, and the third composite material layer 1 and the PP honeycomb panel layer 2 are arranged according to the shape.

[0054] In a preferred embodiment of the present invention, the steel plate layer 3 can be made of high-strength steel with a thickness of 0.7-1.0 mm. The steel plate layer 3 plays a role in rigid protection of the heating film and the internal structure of the battery, preventing the heating film and the internal structure of the battery from receiving severe impact. The second composite material layer 4 and the PP honeycomb plate layer 2 are bonded together by thermosetting and wrap and fix the steel plate layer 3 to prevent pores and gaps between the steel plate layer 3 and other surface layers, improve the overall strength of the material, and reduce the probability of surface layer dislocation during later punching. At the same time, since the steel plate layer 3 can be embedded in the PP honeycomb plate layer 2 after molding, the seismic resistance of the protective plate can be further improved.

[0055] High-strength steel can be placed on the entire surface or the location and size of the steel plate can be determined based on the weak points that may cause puncture risks during vehicle driving. High-strength steel can be selected from common grades such as DP590\DP780\DP980, or stainless steel. Material requirements can be changed according to customer needs. Double-sided electrophoresis is required before the steel plate is composited to ensure adhesion with the composite material layer.

[0056] In the present invention, a plurality of peripheral assembly holes 7 are arranged on the peripheral side of the first composite material layer 6 , and the peripheral assembly holes 7 are arranged downwardly through the second composite material layer 4 , the PP honeycomb panel layer 2 and the third composite material layer 1 in sequence.

[0057] The surrounding assembly holes 7 are arranged at the edge of the integrated heating protection plate and do not pass through the heating film layer 5 and the steel plate layer 3, which can reduce the damage to the insulation layer and the heating layer. Since the hardness of the materials passed by the machine during drilling is similar, the drilling operation can be carried out directly, reducing the hole position tolerance and reducing the difficulty of later assembly. At the same time, the insulation layer and the heating layer are not passed through during drilling, and the connection effect between the insulation layer, the heating layer and the protection layer can also be protected.

[0058] The above describes the connection between the steel plate layer 3 and the composite material layer and the PP honeycomb plate layer, as well as the connection between the heating film layer 5 and the composite material layer. The present invention also improves the connection effect between the steel plate layer 3 and the heating film layer 5 by improving the steel plate layer 3.

[0059] Specifically, the steel plate layer 3 is divided into a first steel plate 301 and a second steel plate 302, and the first steel plate 301 and the second steel plate 302 are respectively located on the left and right sides of the sinking area 8, and a connecting interval for connecting the second composite material layer 4 and the PP honeycomb plate layer 2 is provided between the first steel plate 301 and the second steel plate 302, and an intermediate assembly hole 9 is provided on the connecting interval, which can further improve the protection strength and reduce the stress in the connecting interval.

[0060] At the same time, in particular, the heating layer is also provided with a gap in the connecting area for the middle assembly hole 9 to pass through.

[0061] Ordinary composite materials can bond steel plates and heating films, but the present invention uses S-shaped heating films and partitioned steel plates, which can not only fix the steel plates and heating films in the protective plate at the same time, but also improve the fixing effect between the two and improve the strength of the material.

[0062] The above materials can be laid from bottom to top or from top to bottom. The laying method is optional. Furthermore, due to the complex structure of the steel plate and the heating film, it is easy to move during the transfer after the layering is completed. If the movement occurs, it will not only affect the protection of the plate, but also affect the punching process. At the same time, the steel plate and the heating film are special structures, and it is also easy to be difficult to discharge bubbles during the hot pressing process.

[0063] In order to solve the above problems, see the accompanying drawings of the present invention Figure 4 As shown, the present invention also provides a molding method for preparing the above-mentioned integrated heating protection plate, comprising the following steps:

[0064] Laying the third composite material plate, the PP honeycomb plate, the steel plate, the second composite material plate, the heating film, and the first composite material plate on the pre-pressed bottom plate in order from bottom to top to obtain a prefabricated part;

[0065] The preform is flattened by a roller, and after rolling, the edge of the preform is clamped to move the preform into the mold;

[0066] Among them, after rolling, the first composite material layer, the second composite material layer and the PP honeycomb plate layer are bonded together, and the steel plate layer and the heating film layer are positioned;

[0067] The preform is hot-pressed by a press, and the PP honeycomb panel and the third composite material panel melt and fill the pre-reserved mold cavity as the temperature rises;

[0068] The molded product is taken out of the mold and placed to cool down. After the temperature drops, it is transferred to the laser cutting process and the product is subjected to a hole opening process to obtain an integrated heating protection plate.

[0069] The present invention first performs flat hot pressing, i.e., preheating roller pressing, on the preform, which not only provides pressure to the material, but also provides a certain amount of heat, so that the steel plate and the heating film can be initially connected to the composite material, and the composite materials can also be initially bonded together, preventing the steel plate and the heating film from shifting during the transfer to the mold.

[0070] Furthermore, in order to prevent the preform from moving during the rolling process, the plane rolling includes the following steps:

[0071] The roller is heated to the preheating temperature, and the preform is rolled from the middle to both ends. The preform is fixed during the rolling process. The roller conducts heat from the first composite material layer to the third composite material layer and exhausts the air in the preform.

[0072] Specifically, two identical rollers may be used, with the two roller axes moving relative to each other in the horizontal direction, rotating synchronously in opposite directions, and rotating and fitting together after running to the end of the preform, to perform a cycle of hot pressing.

[0073] The surface temperature of the roller cannot be too high, otherwise it will cause the preform to deform and make it difficult to enter the mold for hot pressing. Therefore, the surface temperature of the roller is 60-100°C. The surface temperature of the roller is mainly controlled by the ambient temperature, and is affected by the factory temperature and the specific material type during specific operation.

[0074] During hot pressing, the mold temperature is: 130℃~170℃, and the mold pressure is selected according to the product design thickness ratio and the mold projection area.

[0075] For the specific mold pressure selection, please refer to the formula T = S*F1*F2 / F table

[0076] During production, the corresponding mold structure is designed according to the different product shapes.

[0077] In particular, the third composite material layer is composed of 2 layers of 400g / ㎡ sheets, and the thickness after molding is 0.3-0.6mm; the second composite material layer is composed of 1-2 layers of 400g / ㎡ sheets, and the thickness after molding is 0.3-0.6mm; the first composite material layer is composed of 2 layers of 200g / ㎡ sheets, and the thickness after molding is 0.25-0.3mm.

[0078] The weight of the third composite material layer is different from that of other composite material layers because after the two layers of 200g / ㎡ sheets are cured and formed, the surface resin can completely cover the PI film of the lower heating film layer to ensure the surface quality of the finished product. The position of the steel plate can be corrected by customizing the tooling. The composite material prepreg sheet itself has a certain viscosity and is not easy to move after the layer is laid, which can ensure the position of the steel plate after forming.

[0079] The following is a specific example of a method for forming an integrated heating protection plate.

[0080] Embodiment 1:

[0081] 1. Select thermosetting resin-based reinforced fiber composite materials as the composite material layer, and pre-treat the materials to be used, including cutting, electrophoresis, surface cleaning and other processes for each layer of materials;

[0082] 2. Lay the materials in layers, and the order of laying is from bottom to top: the third thermosetting resin-based reinforced fiber composite material layer, the PP honeycomb plate layer, the steel plate layer, the second thermosetting resin-based reinforced fiber composite material layer, the heating film layer, and the first thermosetting resin-based reinforced fiber composite material layer;

[0083] The thickness of the third thermosetting resin-based reinforced fiber composite material layer can be selected to be thicker. It is recommended to use 2 layers of 400g / ㎡ sheets, and the thickness after molding is 0.55mm.

[0084] The thickness of the second thermosetting resin-based reinforced fiber composite material layer can be selected to be thinner. It is recommended to use a layer of 400g / ㎡ sheet, and the thickness after molding is 0.4mm;

[0085] The thickness of the first thermosetting resin-based reinforced fiber composite material layer can be selected to be thinner. It is recommended to use 2 layers of 200g / ㎡ sheets, and the thickness after molding is 0.25mm.

[0086] 3. Put the prefabricated parts after layering into the mold and use a press to hot-press them. The PP honeycomb panel will melt and fill the pre-reserved mold cavity as the temperature rises, while the other excess parts will melt and be squeezed out of the mold together with the excess resin of the composite material layer as the pressure of the press increases.

[0087] 4. After the molded product is taken out of the mold, it is placed to cool down. After the temperature drops, it is transferred to the laser cutting process to machine the designed holes on its surface.

[0088] 5. Assemble the bushing or foam layer according to product design requirements, and the product molding process is completed.

[0089] The integrated heating protection plate of this embodiment has a light structure and a thin thickness, and has a light weight after being used in the battery pack. The embodiment is made of multi-layer composite materials by hot pressing, and each layer of material can be fully bonded and in contact with each other, thereby ensuring the airtightness of the battery pack and preventing pores and gaps from forming.

[0090] Through the forming method for producing the above-mentioned integrated heating protection plate of this embodiment, the assembly method is simple, and the hardness of the materials passed by the machine during punching is similar, so that the punching operation can be carried out directly, reducing the hole position tolerance and reducing the difficulty of subsequent assembly. At the same time, preheating roller pressing is used to not only provide pressure to the material, but also provide a certain amount of heat, so that the steel plate and the heating film can be preliminarily connected to the composite material, reducing the probability of surface layer dislocation during subsequent punching.

[0091] The above embodiments are only exemplary embodiments of the present application and are not intended to limit the present application. The protection scope of the present application is defined by the claims. Those skilled in the art may make various modifications or equivalent substitutions to the present application within the essence and protection scope of the present application, and such modifications or equivalent substitutions shall also be deemed to fall within the protection scope of the present application.

Claims

1. An integrated heating protection plate, characterized in that: The structure comprises, from bottom to top, a third composite material layer (1), a PP honeycomb plate layer (2), a steel plate layer (3), a second composite material layer (4), a heating film layer (5), and a first composite material layer (6); the PP honeycomb plate layer (2) is provided with a sinking area (8) capable of being fitted with the steel plate layer (3); and the third composite material layer (1) and the PP honeycomb plate layer (2) are arranged in a conformal manner; The third composite material layer (1), the second composite material layer (4), and the first composite material layer (6) are all thermosetting resin-based reinforced fiber composite materials; The second composite material layer (4) and the first composite material layer (6) are bonded together by thermosetting and wrap around and fix the heating film layer (5); the second composite material layer (4) and the PP honeycomb panel layer (2) are bonded together by thermosetting and wrap around and fix the steel panel layer (3).

2. The integrated heating protection plate according to claim 1, characterized in that: The steel plate layer (3) is divided into a first steel plate (301) and a second steel plate (302), the first steel plate (301) and the second steel plate (302) being located on the left and right sides of the sinking area (8) respectively, an intermediate assembly hole (9) is provided between the first steel plate (301) and the second steel plate (302), the intermediate assembly hole (9) sequentially passing through the first composite material layer (6), the second composite material layer (4), the PP honeycomb plate layer (2), and the third composite material layer (1).

3. A molding method for preparing an integrated heating protection plate according to any one of claims 1-2, characterized in that: The steps include: Laying the third composite material plate, the PP honeycomb plate, the steel plate, the second composite material plate, the heating film, and the first composite material plate on the pre-pressed bottom plate in order from bottom to top to obtain a prefabricated part; Rolling the preform in a flat surface with a roller, clamping the edge of the preform after rolling, and moving the preform into a mold; Among them, after rolling, the first composite material layer, the second composite material layer and the PP honeycomb plate layer are bonded together, and the steel plate layer and the heating film layer are positioned; The preform is hot-pressed by using a press, and the PP honeycomb panel and the third composite material panel melt and fill the pre-reserved mold cavity as the temperature rises; The molded product is taken out of the mold and placed to cool down. After the temperature drops, it is transferred to the laser cutting process and the product is subjected to a hole-opening process to obtain the integrated heating protection plate.

4. The molding method according to claim 3, characterized in that: The plane rolling comprises the following steps: The roller is heated to a preheating temperature, and the preform is rolled from the middle to both ends. The roller conducts heat from the first composite material layer to the third composite material layer and exhausts air in the preform.

5. The molding method according to claim 4, characterized in that: The plane rolling also includes the following steps: The two roller shafts of the rollers move relative to each other in the horizontal direction, rotate synchronously in opposite directions, and rotate and fit together after running to the end of the preform, performing a cycle of hot pressing.

6. The molding method according to claim 4, characterized in that: The surface temperature of the roller is 60-100°C.

7. The molding method according to claim 3, characterized in that: In the hot pressing step, the mold temperature is: 130°C to 170°C; The mold pressure selection formula is T=S*F1*F2 / F table.

8. The molding method according to claim 1, characterized in that: The third composite material layer is composed of two layers of 400g / ㎡ sheets, and the thickness after molding is 0.3-0.6mm.

9. The molding method according to claim 1, characterized in that: The second composite material layer is composed of 1-2 layers of 400g / ㎡ sheet, and the thickness after molding is 0.3-0.6mm.

10. The molding method according to claim 1, characterized in that: The first composite material layer is composed of two layers of 200g / ㎡ sheets, and the thickness after molding is 0.25-0.3mm.

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