A lightweight battery pack composite material bracket

Abstract

This utility model relates to the field of new energy battery support structure technology, specifically to a lightweight battery pack composite material bracket, including a skeleton layer and a reinforcing layer covering the skeleton layer. Connection holes are provided on the skeleton layer and the reinforcing layer, with metal bushings pre-embedded in the connection holes. The skeleton layer includes a lower support plate connected to the battery pack and an upper support plate connected to the vehicle base. The reinforcing layer includes outer reinforcing ribs covering the outer end faces of the lower and upper support plates and inner reinforcing ribs covering the inner end face of the upper support plate. The skeleton layer is made of continuous fiber nylon, and the reinforcing layer is made of short fiber plastic. The upper and lower support plates are connected by side support plates, and the reinforcing layer also includes a side covering layer covering the side support plates. This battery pack composite material bracket solution achieves both lightweight design and high load-bearing capacity while reducing costs.

Description

Technical Field

[0001] This utility model relates to the field of new energy battery support structure technology, specifically providing a lightweight battery pack composite material bracket. Background Technology

[0002] New energy battery packs are the core energy units of new energy equipment such as electric vehicles and energy storage systems. They are usually composed of multiple cells or battery modules, and are equipped with thermal management systems, battery management systems and structural protective components to form an integrated device that can provide safe and reliable power supply. It is not only the smallest functional unit of the battery, but also a key component to achieve high energy density, long cycle life and safety. In order to ensure the stable operation of the battery pack and improve its service life, the fixed support of the battery pack plays an important role.

[0003] Currently, the brackets for fixing battery packs are mostly made of metal or all-composite materials, which have the following problems: Metal materials (such as steel or aluminum alloy) are usually made by stamping, welding or casting. Such metal brackets have disadvantages such as heavy weight, affecting the vehicle's driving range and easy corrosion; All-composite material solutions are lightweight, but brackets made of pure plastic or ordinary engineering plastics often have insufficient structural strength and connection point strength, especially at bolt fastening points where creep and loosening are prone to occur. They cannot meet the strength and durability requirements of commercial vehicles and are difficult to meet the high load (≥3g vertical impact) and vibration requirements of commercial vehicles.

[0004] In the prior art, the following documents relate to battery pack support devices made of composite materials: 1. The patent document with publication number "CN119458978A" and titled "A Method for Preparing a Fiber Braided Composite Material Subframe and the Subframe" includes a composite material frame and metal connectors. The foam core material is processed into a support template, and metal inserts are set on the support template. A reinforcing frame composed of fiber material is woven in a three-dimensional braiding method outside the support template and metal inserts. Resin is injected into the reinforcing frame and cured to form the composite material frame of the subframe. This solution has significant weight reduction, meets the requirements of lightweighting, and has high load-bearing capacity, but the process is complex and the cost is high.

[0005] 2. The patent document with publication number "CN117400710A" and title "A novel composite material vehicle and battery pack connection structure" includes a seat and a battery pack. The seat includes a front panel, two side panels, a bottom plate and a rear panel. The seat is manufactured using a carbon fiber integral molding process. This solution uses a CFRP seat to replace the top cover as a whole, which can reduce the overall weight, but it cannot solve the problem of low local connection strength of the bracket.

[0006] In summary, there is a need to design a composite material support for battery packs that balances lightweight, high load-bearing capacity, and low cost. Utility Model Content

[0007] To address the aforementioned problems, this invention provides a lightweight battery pack composite material bracket, which achieves lightweight design, reduces maintenance costs, increases service life, and enhances load-bearing capacity.

[0008] This utility model provides a lightweight battery pack composite material bracket, including a skeleton layer and a reinforcing layer covering the skeleton layer. The skeleton layer and the reinforcing layer have connection holes, and metal bushings are pre-embedded in the connection holes. The skeleton layer includes a lower support plate connected to the battery pack and an upper support plate connected to the vehicle base. The reinforcing layer includes an outer reinforcing rib group covering the outer end face of the lower support plate and the upper support plate, and an inner reinforcing rib group covering the inner end face of the upper support plate. The skeleton layer is made of continuous fiber nylon, and the reinforcing layer is made of short fiber plastic.

[0009] Furthermore, the connection hole includes a lower connection hole located at the main connection bearing between the lower support plate and the battery pack. Specifically, the lower connection hole is located on the side end of the lower support plate away from the upper support plate; the lower connection hole includes a plurality of evenly arranged holes.

[0010] Furthermore, the outer reinforcing rib group includes a reinforcing rib area one and a reinforcing rib area two covering the outer end face of the lower support plate. The reinforcing rib area one includes a horizontal reinforcing rib one and a vertical reinforcing rib one arranged vertically and alternately. The lower connecting hole is located between the horizontal reinforcing rib one and the vertical reinforcing rib one.

[0011] Furthermore, the second reinforcing rib area includes two transverse reinforcing ribs and two longitudinal reinforcing ribs arranged vertically and alternately, with the second transverse reinforcing rib arranged parallel to the first transverse reinforcing rib; the second longitudinal reinforcing rib includes multiple ribs connected between the first transverse reinforcing rib and the second transverse reinforcing rib near the second transverse reinforcing rib.

[0012] Furthermore, the outer reinforcing rib group includes a longitudinal reinforcing rib three extending upward from the second longitudinal reinforcing rib toward the outer end face of the upper support plate.

[0013] Furthermore, the length of the third longitudinal stiffener located in the middle is less than the length of the third longitudinal stiffeners located on both sides; the connecting hole includes an upper connecting hole located at the main connecting bearing between the upper support plate and the vehicle base, specifically, the upper connecting hole is located on the side of the third longitudinal stiffener in the middle away from the lower support plate and between the third longitudinal stiffeners on both sides.

[0014] Furthermore, the inner reinforcing rib assembly includes a central reinforcing rib located circumferentially around the upper connecting hole, and side reinforcing ribs extending from the corner of the central reinforcing rib toward the lower support plate.

[0015] Furthermore, the inner reinforcing rib group also includes four longitudinal reinforcing ribs and four transverse reinforcing ribs arranged vertically and alternately.

[0016] Furthermore, the lower support plate and the upper support plate are L-shaped, and the upper support plate and the lower support plate are connected by a side support plate; the reinforcing layer also includes a side covering layer covering the side support plate.

[0017] Furthermore, the side support plate is a right-angled triangular plate structure, with the hypotenuse of the side support plate inclined from top to bottom in the direction from the outer edge of the upper support plate to the outer edge of the lower support plate.

[0018] Compared with the prior art, the present invention can achieve the following beneficial effects: 1. The battery pack composite material bracket in this utility model uses a continuous fiber nylon organic plate as the core load-bearing skeleton, combined with short fiber reinforced plastic injection molding, and pre-embeds metal bushings with special surface structure treatment at key connection parts. This enables the bracket to achieve lightweighting, with an overall weight reduction of 30-50%. It can achieve a synergistic improvement in lightweighting and mechanical load-bearing performance, which can improve the vehicle's driving range, reduce assembly processes and subsequent maintenance costs. The pre-embedded organic plate and metal bushing can ensure overall strength and vibration resistance.

[0019] 2. The battery pack composite material bracket in this utility model not only solves the technical problem of easy creep and loosening of composite material connection points and provides a reliable connection interface comparable to metal, but also achieves a high degree of integration of complex structural features by using injection molding process, which greatly reduces the number of parts and assembly steps. Through injection molding, a complex three-dimensional structure integrating multiple features can be manufactured at one time, freeing it from the constraints of metal stamping process on shape, and enabling mass production of products.

[0020] 3. The composite material body of the battery pack composite material bracket in this utility model has excellent corrosion resistance, which eliminates the risk of failure caused by corrosion, greatly extends the service life, reduces the total life cycle cost, and greatly improves the reliability and safety of the battery pack. Ultimately, it shows significant advantages in terms of lightweight, reliability, production efficiency and overall cost. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the structure of the battery pack composite material bracket provided according to an embodiment of the present utility model. Figure 1 ; Figure 2 This is a schematic diagram of the structure of the battery pack composite material bracket provided according to an embodiment of the present utility model. Figure 2 ; Figure 3 This is a schematic diagram of the skeleton layer in the composite material support of the battery pack according to an embodiment of the present invention; Figure 4 This is an installation diagram of the battery pack composite material bracket provided according to an embodiment of the present utility model; Figure 5It is a random vibration RMS stress cloud diagram of a traditional iron battery pack support. Figure 6 This is a random vibration RMS stress cloud diagram of the battery pack bracket provided according to an embodiment of the present invention.

[0022] The reference numerals in the attached drawings include: lower support plate 1, upper support plate 2, outer reinforcing rib group 3, inner reinforcing rib group 4, lower connecting hole 5, transverse reinforcing rib 1 6, longitudinal reinforcing rib 1 7, transverse reinforcing rib 2 8, longitudinal reinforcing rib 2 9, longitudinal reinforcing rib 3 10, middle reinforcing rib 11, side reinforcing rib 12, transverse reinforcing rib 4 13, longitudinal reinforcing rib 4 14, side support plate 15, and upper connecting hole 16. Detailed Implementation

[0023] To make the objectives, technical solutions, and advantages of this utility model clearer, the following description is provided in conjunction with the appendix. Figure 1-6 The present invention will be further described in detail below with reference to specific embodiments. It should be understood that the specific embodiments described herein are only for explaining the present invention and do not constitute a limitation thereof.

[0024] A lightweight battery pack composite material support includes a skeleton layer and a reinforcing layer covering the skeleton layer. Connection holes are provided on both the skeleton layer and the reinforcing layer, and metal bushings are pre-embedded in the connection holes. The skeleton layer is made of continuous fiber nylon, and the reinforcing layer is made of short fiber plastic. Specifically, the skeleton layer uses continuous long glass fiber nylon, and the reinforcing layer uses short glass fiber reinforced plastic (PA6+GF50). The continuous long glass fiber nylon organic skeleton layer can be coated with thermosetting resin or thermoplastic resin. The injection-molded body covers the skeleton layer and tightly fills the metal bushing, forming a dense, integrated structure, achieving a synergistic improvement in both lightweighting and mechanical properties of the support.

[0025] The skeleton layer includes a lower support plate 1 connected to the battery pack and an upper support plate 2 connected to the vehicle base. The lower support plate 1 and the upper support plate 2 are L-shaped. The upper support plate 2 and the lower support plate 1 are connected by a side support plate 15. The reinforcement layer also includes a side covering layer covering the side support plate 15. The side support plate 15 is a right-angled triangular plate structure. The hypotenuse of the side support plate 15 is inclined from top to bottom from the outer edge of the upper support plate 2 toward the outer edge of the lower support plate 1. The skeleton layer of this structure provides stable and reliable support.

[0026] The reinforcing layer includes an outer reinforcing rib group 3 covering the outer end faces of the lower support plate 1 and the upper support plate 2, and an inner reinforcing rib group 4 covering the inner end face of the upper support plate 2. Figure 4This diagram illustrates the installation of a composite material support frame for a battery pack. A represents the battery pack, M represents the lower support plate 1 within the reinforcing frame layer, and N represents the upper support plate 2 within the reinforcing frame layer. The lower support plate 1 is connected to the battery pack, and the upper end of the upper support plate 2 will connect to the vehicle floor. Each battery pack is equipped with... Figure 4 The multiple supports shown.

[0027] The connection holes include lower connection holes 5 located at the main connection bearing between the lower support plate 1 and the battery pack. Specifically, the lower connection holes 5 are located on the side of the lower support plate 1 away from the upper support plate 2. The lower connection holes 5 include a plurality of evenly arranged holes. The connection holes include upper connection holes 16 located at the main connection bearing between the upper support plate 2 and the vehicle base. Metal bushings with special surface structure treatment are pre-embedded in key connection parts. While ensuring the connection bearing performance, the bracket is lightweight. This not only solves the technical problem of easy creep and relaxation of composite material connection points, but also provides a reliable connection interface comparable to metal. At the same time, the injection molding process is used to achieve a high degree of integration of complex structural features, which greatly reduces the number of parts and assembly steps.

[0028] The outer reinforcing rib group 3 includes a reinforcing rib area 1 and a reinforcing rib area 2 covering the outer end face of the lower support plate 1. The reinforcing rib area 1 includes a horizontal reinforcing rib 16 and a vertical reinforcing rib 17 arranged vertically and alternately. The lower connecting hole 5 is located between the horizontal reinforcing rib 16 and the vertical reinforcing rib 17. The reinforcing rib area 2 includes a horizontal reinforcing rib 28 and a vertical reinforcing rib 29 arranged vertically and alternately. The horizontal reinforcing rib 28 is arranged parallel to the horizontal reinforcing rib 16. The vertical reinforcing rib 29 includes multiple horizontal reinforcing ribs 16 and 28 connected near the horizontal reinforcing rib 28. The horizontal reinforcing rib 16 and the vertical reinforcing rib 17 are staggered from the lower connecting hole 5 to avoid interference. The horizontal reinforcing rib 16, the vertical reinforcing rib 17, the horizontal reinforcing rib 28, and the vertical reinforcing rib 29 can improve the support force of the bracket and improve the stability of the connection with the battery pack.

[0029] The outer reinforcing rib group 3 includes a longitudinal reinforcing rib 3 10 extending from the longitudinal reinforcing rib 2 9 toward the outer end face of the upper support plate 2. The length of the longitudinal reinforcing rib 3 10 in the middle is less than the length of the longitudinal reinforcing ribs 3 10 on both sides. The upper connecting hole 16 is located on the side of the longitudinal reinforcing rib 3 10 in the middle away from the lower support plate 1, and the upper connecting hole 16 is located between the longitudinal reinforcing ribs 3 10 on both sides, so that the reasonable arrangement of each structure can be achieved in a limited space.

[0030] The inner reinforcing rib group 4 includes a central reinforcing rib 11 located circumferentially around the upper connecting hole 16. The central reinforcing rib 11 also extends to the corner of the lower support plate 1 and is provided with side reinforcing ribs 12. The inner reinforcing rib group 4 also includes vertically staggered longitudinal reinforcing ribs 14 and transverse reinforcing ribs 13. The central reinforcing rib 11, side reinforcing ribs 12, longitudinal reinforcing ribs 14 and transverse reinforcing ribs 13 can enhance the support performance of the upper support plate 2 and strengthen the connection strength between the bracket and the vehicle base.

[0031] In this embodiment, the skeleton layer is specifically made of 2.0mm thick continuous glass fiber / nylon PA66 organic board with 30% fiber volume content, which is hot-pressed at 240℃ to provide the core load-bearing function. The injection-molded matrix is ​​made of PA6-GF50 (50% short glass fiber), which covers the skeleton layer and metal bushing at a barrel temperature of 260℃ and an injection pressure of 80MPa, forming a complex geometric shape and reinforcing ribs in one piece. The metal bushing is placed at the bolt connection, and its surface has a knurling depth of 0.2mm to ensure that the bonding strength with the composite material is higher than that with the matrix itself.

[0032] Simulation and experimental verification show that this support achieves a significant 35% weight reduction compared to the original steel stamped support. Constrained modal analysis indicates that its natural frequency is lower than that of the metal support, effectively avoiding the main frequency band of road excitation (usually <100Hz) and thus avoiding the risk of resonance. The results of the constrained modal analysis are shown in Table 1 below. Table 1:

[0033] The results of random vibration analysis are as follows: Figure 5 , Figure 6 As shown in Table 2 below, Figure 5 This is an RMS stress contour plot of the iron battery pack support under random vibration. Figure 6 The table below shows the random vibration RMS stress cloud diagram of the battery pack bracket in this application. Table 2 shows the structure analyzed by random vibration. The random vibration analysis shows that under the PSD load spectrum of 0.00001g² / Hz in the frequency range of 50-200Hz, the maximum equivalent stress is 9.1MPa, which is far lower than the allowable stress of the material (35MPa). Moreover, there is no risk of loosening at the connection point, and the fatigue life meets the reliability requirements of commercial vehicle fatigue life.

[0034] Table 2:

[0035] Although embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions, and variations to the above embodiments within the scope of the present invention.

[0036] The specific embodiments of this utility model described above do not constitute a limitation on the scope of protection of this utility model. Any other corresponding changes and modifications made based on the technical concept of this utility model should be included within the scope of protection of the claims of this utility model.

Claims

1. A lightweight battery pack composite material bracket, characterized in that, It includes a skeleton layer and a reinforcing layer covering the skeleton layer. The skeleton layer and the reinforcing layer are provided with connection holes, and metal bushings are pre-embedded in the connection holes. The skeleton layer includes a lower support plate (1) connected to the battery pack and an upper support plate (2) connected to the vehicle base. The reinforcing layer includes an outer reinforcing rib group (3) covering the outer end face of the lower support plate (1) and the upper support plate (2) and an inner reinforcing rib group (4) covering the inner end face of the upper support plate (2). The skeleton layer is made of continuous fiber nylon material, and the reinforcing layer is made of short fiber plastic material.

2. The lightweight battery pack composite material bracket according to claim 1, characterized in that, The connection hole includes a lower connection hole (5) located at the main connection bearing between the lower support plate (1) and the battery pack. Specifically, the lower connection hole (5) is located at the side end of the lower support plate (1) away from the upper support plate (2). The lower connection hole (5) includes a plurality of evenly arranged holes.

3. The lightweight battery pack composite material bracket according to claim 2, characterized in that, The outer reinforcing rib group (3) includes a reinforcing rib area one and a reinforcing rib area two covering the outer end face of the lower support plate (1). The reinforcing rib area one includes a horizontal reinforcing rib one (6) and a longitudinal reinforcing rib one (7) arranged vertically and alternately. The lower connecting hole (5) is located between the horizontal reinforcing rib one (6) and the longitudinal reinforcing rib one (7).

4. The lightweight battery pack composite material bracket according to claim 3, characterized in that, The second reinforcing rib area includes two horizontal reinforcing ribs (8) and two longitudinal reinforcing ribs (9) arranged vertically and alternately. The second horizontal reinforcing rib (8) is arranged parallel to the first horizontal reinforcing rib (6). The second longitudinal reinforcing rib (9) includes multiple ribs connected between the first horizontal reinforcing rib (6) and the second horizontal reinforcing rib (8) near the second horizontal reinforcing rib (8).

5. The lightweight battery pack composite material bracket according to claim 4, characterized in that, The outer reinforcing rib group (3) includes a longitudinal reinforcing rib three (10) extending from the longitudinal reinforcing rib two (9) toward the outer end face of the upper support plate (2).

6. The lightweight battery pack composite material bracket according to claim 5, characterized in that, The length of the longitudinal reinforcing rib three (10) located in the middle is less than the length of the longitudinal reinforcing rib three (10) located on both sides; the connecting hole includes the upper connecting hole (16) located at the main connecting bearing between the upper support plate (2) and the vehicle base, specifically, the upper connecting hole (16) is located on the side of the longitudinal reinforcing rib three (10) in the middle away from the lower support plate (1) and between the longitudinal reinforcing rib three (10) on both sides.

7. The lightweight battery pack composite material bracket according to claim 6, characterized in that, The inner reinforcing rib group (4) includes a central reinforcing rib (11) located circumferentially around the upper connecting hole (16), and a side reinforcing rib (12) extending from the corner of the central reinforcing rib (11) toward the lower support plate (1).

8. The lightweight battery pack composite material bracket according to claim 7, characterized in that, The inner reinforcing rib group (4) also includes four longitudinal reinforcing ribs (14) and four transverse reinforcing ribs (13) arranged vertically and alternately.

9. The lightweight battery pack composite material bracket according to claim 8, characterized in that, The lower support plate (1) and the upper support plate (2) are L-shaped, and the upper support plate (2) and the lower support plate (1) are connected by a side support plate (15); the reinforcing layer also includes a side covering layer covering the side support plate (15).

10. The lightweight battery pack composite material bracket according to claim 9, characterized in that, The side support plate (15) is a right-angled triangular plate structure, and the hypotenuse of the side support plate (15) is inclined from the outside of the upper support plate (2) to the outside of the lower support plate (1) from top to bottom.

Images