Bottom protection plate of power battery

Abstract

The utility model relates to the technical field of automobile battery accessories, in particular to a power battery bottom protection plate which is of an integrally formed structure and sequentially comprises a lower fiber fabric layer, a flame-retardant foam layer, a metal plate layer and an upper fiber fabric layer from bottom to top, adjacent layers are laminated and stacked, and the surfaces of the layers are consistent in size; wherein the flame-retardant foam layer and the metal plate layer are cured into a whole through mould pressing; the battery pack bottom guard plate can effectively solve the problem that the structural form of the existing battery pack bottom guard plate cannot meet the requirements of new working conditions.

Description

Technical Field

[0001] The utility model relates to the technical field of automobile battery accessories, in particular to a power battery bottom guard plate. Background Art

[0002] The battery bottom guard plate can effectively prevent obstacles from invading the battery cell when the new energy battery is supported or scraped, thereby reducing the risk of short circuit and thermal runaway of the battery cell.

[0003] The current mainstream solution for the existing battery pack bottom guard plate is a 0.7mm steel plate with electrophoretic surface and a PVC layer sprayed on the bottom of the outer surface for corrosion and scratch protection. At the same time, it is equipped with a mica board for fire prevention. The new regulations are gradually tightening the safety performance requirements for the bottom of power batteries. The structure of the traditional battery pack steel plate can no longer meet the requirements of the new working conditions, and the thickening of the steel plate will greatly reduce the range of the power battery. Utility Model Content

[0004] Technical issues solved

[0005] In view of the above-mentioned shortcomings of the prior art, the utility model provides a power battery bottom guard plate, which can effectively solve the problem that the structural form of the existing battery pack bottom guard plate can no longer meet the requirements of new working conditions.

[0006] Technical Solution

[0007] In order to achieve the above objectives, the present invention is implemented through the following technical solutions:

[0008] The utility model provides a power battery bottom guard plate, which is an integrally formed structure. The bottom guard plate comprises, from bottom to top, a lower fiber fabric layer, a flame retardant foam layer, a metal plate layer and an upper fiber fabric layer. Adjacent layers are laminated and stacked, and the surface sizes of the layers are consistent. The flame retardant foam layer and the metal plate layer are cured into a whole by molding.

[0009] Furthermore, the lower fiber fabric layer, the flame retardant foam layer, the metal plate layer and the upper fiber fabric layer are integrally formed by filling resin and heating and curing the resin.

[0010] Furthermore, the metal plate layer is made of a thin plate made of SPCC or SUS304.

[0011] Furthermore, the thickness of the metal plate layer is 0.5-1.2 mm, and continuous rib protrusions are formed on the metal plate layer through a stamping process.

[0012] Furthermore, the flame retardant foam layer is made of polyurethane-based hard foam, and the thickness of the flame retardant foam layer is 2-8 mm.

[0013] Furthermore, the lower fiber fabric layer and the upper fiber fabric layer are both made of multi-axially woven glass fiber mesh, and the resin completely covers the lower fiber fabric layer and the upper fiber fabric layer.

[0014] Beneficial Effects

[0015] Compared with the known public technology, the technical solution provided by the utility model has the following beneficial effects:

[0016] This product avoids subsequent secondary surface treatment through the integrated molding of the lower fiber fabric layer, the flame retardant foam layer, the metal plate layer and the upper fiber fabric layer, thereby increasing the thermal runaway protection area at the bottom of the overall battery shell. Compared with the solution of paving mica boards in the prior art, the integrated molding of the bottom guard plate can reduce manufacturing costs. The main body is molded and cured by the metal plate layer and the flame retardant foam layer, which can effectively prevent thermal shock of the battery cell when the battery unexpectedly experiences thermal runaway. At the same time, the flame retardant foam layer is used to produce an expanding insulation layer, which can effectively ensure that the outer surface temperature of the battery pack is lower than 200°C.

[0017] In addition, the metal plate layer is combined with the upper and lower fiber fabric layers to greatly improve the rigidity and strength of the bottom guard plate without increasing the weight of the bottom guard plate, thereby improving the bottom guard plate's resistance to scratches and bottoming risks and improving the safety of the power battery. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments or the prior art descriptions are briefly introduced below. Obviously, the drawings described below are only some embodiments of the utility model, and for ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0019] Figure 1 It is a schematic diagram of the structure of each layer of the bottom guard plate of the utility model;

[0020] The reference numerals in the figure represent respectively: 10, lower fiber fabric layer; 20, flame retardant foam layer; 30, metal plate layer; 40, upper fiber fabric layer; 50, resin. DETAILED DESCRIPTION

[0021] In order to make the purpose, technical solution and advantages of the embodiment of the utility model clearer, the technical solution in the embodiment of the utility model will be clearly and completely described below in conjunction with the drawings in the embodiment of the utility model. Obviously, the described embodiment is a part of the embodiment of the utility model, not all of the embodiments. Based on the embodiment of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0022] The utility model is further described below in conjunction with embodiments.

[0023] Example:

[0024] The utility model provides a power battery bottom guard plate, which is mainly used at the bottom of the battery pack of new energy electric vehicles. The product can effectively prevent obstacles from invading the battery cells and causing the risk of short circuit and thermal runaway of the battery cells. In addition, in the working condition of the battery cells with the battery cell explosion-proof valves facing downward, the bottom guard plate itself can not only prevent the bottoming and bottom scraping conditions, but also meet the requirements of thermal runaway of the battery cells in the event of internal thermal runaway, without the need to add a mica plate for fire protection.

[0025] Reference Figure 1 The bottom guard plate of this product is an integrated structure, and the bottom guard plate includes a lower fiber fabric layer 10, a flame retardant foam layer 20, a metal plate layer 30 and an upper fiber fabric layer 40 from bottom to top. Adjacent layers are laminated and stacked, and the surface sizes of the layers are consistent; wherein the flame retardant foam layer 20 and the metal plate layer 30 are cured into a whole through molding.

[0026] Specifically, in the integrated molding, the resin 50 is filled between the lower fiber fabric layer 10, the flame retardant foam layer 20, the metal plate layer 30 and the upper fiber fabric layer 40, and the integrated molding is achieved by heating and curing the resin 50. The thermosetting resin 50 is used to complete the bonding and fixing molding between the layers, so that the bottom guard plate body also has good insulation, corrosion resistance and scratch resistance.

[0027] Among them, in this embodiment, the flame retardant foam layer 20 preferably adopts polyurethane-based hard foam, and the thickness of the flame retardant foam layer 20 is 2-8mm. The specific application thickness is selected according to the actual project. By placing the metal plate layer 30 in a foam molding mold for integral molding, the flame retardant foam is bonded to the metal plate under pressure by pressurizing the foam mold, and solidified under appropriate temperature and pressure. The metal plate layer 30 in this embodiment is made of a thin plate made of SPCC or SUS304, and the thickness of the metal plate layer 30 is 0.5-1.2mm. The specific application thickness is selected according to the actual project.

[0028] Since the melting point of metal is 1538°C, and the thermal runaway temperature of lithium battery cells is about 1200°C, the metal plate layer 30 can effectively prevent the impact of the battery cells. At the same time, by utilizing the high flame retardancy of polyurethane foam, the flames can be effectively prevented from spilling out when thermal runaway occurs in new energy batteries. In addition, when subjected to thermal shock, polyurethane flame retardant foam can produce an expanded insulation layer, which helps to effectively ensure that the temperature of the outer surface of the battery pack is below 200°C. The flame retardant properties of this foam make it less likely to burn when encountering high temperatures, thereby improving the safety of the battery pack.

[0029] In addition, in this embodiment, the metal plate layer 30 is preferably made of a thin plate made of SPCC or SUS304. In practical applications, continuous rib protrusions can be formed on the metal plate layer 30 by a stamping process, and the overall strength of the metal plate layer 30 thin plate can be greatly improved by the design of the rib protrusions. The thickness of the rib protrusions is consistent with the thickness of the plate body, and the shape of the rib protrusions can be cross-shaped, rectangular, or honeycomb hexagonal, etc.

[0030] At the same time, in this embodiment, preferably, the lower fiber fabric layer 10 and the upper fiber fabric layer 40 are both made of multi-axially woven glass fiber mesh, and the resin 50 completely covers the lower fiber fabric layer 10 and the upper fiber fabric layer 40. The high strength and rigidity of the glass fiber mesh can withstand greater pressure and bending stress, and the rigidity and strength of the bottom guard plate are greatly improved without increasing the weight of the bottom guard plate, thereby improving the bottom protection plate's anti-scratch and bottoming risk, and improving the safety of the power battery.

[0031] At the same time, the good flame retardant properties of the warp-knitted glass fiber mesh can effectively prevent the spread of flames when thermal runaway occurs in the battery pack, thereby improving the safety of the vehicle.

[0032] The following is a brief description of the one-piece molding process of the bottom guard plate in this embodiment:

[0033] 1. Cut the metal plate and warp knitted fabric according to the size of the bottom guard plate product drawing;

[0034] 2. Place the cut metal sheet into the foam forming mold for one-piece forming;

[0035] 3. Place the fiber fabric, metal plate, polyurethane foam, and fiber fabric of the battery bottom guard plate in the preforming mold from bottom to top to process the battery bottom guard plate preform;

[0036] 4. Place the preform in the mold, close the mold, and prepare to inject 50% resin. At the same time, control the mold temperature to 70-180°C and the vacuum degree to be no greater than -0.085MPa;

[0037] 5. After the injection is completed, the mold is heated for 3 to 5 minutes and the mold is opened for demoulding;

[0038] The whole production process is completed by cutting off the waste edges of the product and opening the connecting holes through machining.

[0039] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some of the technical features therein by equivalents. These modifications or replacements will not cause the essence of the corresponding technical solutions to deviate from the protection scope of the technical solutions of the embodiments of the present invention.

Claims

1. A power battery bottom guard plate, characterized in that: The bottom guard plate is an integrally formed structure, and includes, from bottom to top, a lower fiber fabric layer, a flame retardant foam layer, a metal plate layer and an upper fiber fabric layer. Adjacent layers are laminated and stacked, and the surface sizes of the layers are consistent. The flame retardant foam layer and the metal plate layer are cured into a whole by molding.

2. A power battery bottom guard plate according to claim 1, characterized in that: The lower fiber fabric layer, the flame retardant foam layer, the metal plate layer and the upper fiber fabric layer are filled with resin, and the resin is heated and cured to achieve integral molding.

3. A power battery bottom guard plate according to claim 1, characterized in that: The metal plate layer is made of a thin plate of SPCC or SUS304.

4. A power battery bottom guard plate according to claim 2, characterized in that: The thickness of the metal plate layer is 0.5-1.2 mm.

5. A power battery bottom guard plate according to claim 3, characterized in that: Continuous rib protrusions are formed on the metal plate layer through a stamping process.

6. A power battery bottom guard plate according to claim 1, characterized in that: The flame retardant foam layer is made of polyurethane-based hard foam.

7. A power battery bottom guard plate according to claim 6, characterized in that: The thickness of the flame retardant foam layer is 2-8 mm.

8. A power battery bottom guard plate according to claim 2, characterized in that: The lower fiber fabric layer and the upper fiber fabric layer both adopt multi-axially woven glass fiber mesh, and the resin completely covers the lower fiber fabric layer and the upper fiber fabric layer.

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