Battery module beam structure and battery pack structure

Abstract

The utility model discloses a kind of module beam structure and battery pack structure for battery module, module beam structure includes beam body ontology;The sleeve structure that projects downward is provided at the bottom of beam body ontology;The beam body ontology is hollow structure, and inside is provided with reinforcing plate.Battery pack structure includes the module beam structure vertically arranged on the mounting bottom plate;Bottom plate connecting hole is provided on the mounting bottom plate of battery pack structure, the sleeve structure of the bottom of module beam structure is inserted in the inside of bottom plate connecting hole, and module beam structure is fixedly arranged on mounting bottom plate by sleeve structure;Battery module is arranged between adjacent module beam structure, and battery module is fixed by the pre-tightening force exerted between adjacent module beam structure limit.The battery pack structure of the utility model has good structural strength: modal is 2.45% than existing structure gain, can take into account the structural strength and lightweight design of battery pack structure, with simple structure, low in cost, few parts, the advantages such as simple processing technology.

Description

Technical Field

[0001] This utility model relates to the field of battery technology, specifically to a module beam structure for battery modules and a battery pack structure. Background Technology

[0002] New energy vehicles, as a key area for the transformation and upgrading of the current automotive industry, primarily rely on high-performance power battery systems for their power source. However, while the energy density of power batteries continues to improve, their safety issues are becoming increasingly prominent, becoming one of the key factors restricting the further development of new energy vehicles. Among these, collision safety is an important component of structural safety. Especially in extreme conditions such as traffic accidents, the structural strength and stability of the battery module housing directly affect the safety performance of the entire vehicle. Therefore, optimizing the structural design of the battery pack while ensuring the structural strength and impact resistance of the module has become a key focus of current technological research and development.

[0003] Currently, the most common power battery pack structure in the market typically consists of a profiled liquid-cooled base plate combined with module beams, die-cast metal end plates, connecting pieces, steel straps, castings, and sleeves. While this structure can meet the structural support requirements of the module during assembly and the safety performance during use to a certain extent, it has several shortcomings. First, this solution involves a large variety of components and a complex structure, with cumbersome processing and assembly processes and numerous welding steps, resulting in long manufacturing cycles, high costs, and reduced overall vehicle assembly efficiency. Second, due to the extensive use of die-cast metal parts, connecting components, and reinforcements, the overall module weight is significant, severely impacting battery pack quality control and the improvement of vehicle energy density, thus limiting the driving range of new energy vehicles and the development of lightweight vehicles.

[0004] Therefore, how to reduce the number of components, simplify processing and assembly processes, reduce system costs, and significantly reduce the overall weight of modules and battery packs while ensuring the structural strength, safety and service life of battery packs, and improve energy density per unit mass has become an urgent technical problem to be solved in the field of power battery structure design. Utility Model Content

[0005] To overcome the shortcomings of the above-mentioned technologies, the purpose of this utility model is to provide a module beam structure and battery pack structure for battery modules, which solves the problems of low energy density caused by numerous parts, complex processes, high costs, and heavy weight of the battery pack box structure, and has the advantages of high structural strength and lightweight.

[0006] To achieve the above objectives, the technical solution adopted by this utility model is as follows:

[0007] A module beam structure for a battery module is characterized by: including a beam body; a downwardly protruding sleeve structure at the bottom of the beam body; and the beam body being a hollow structure with internal reinforcing plates.

[0008] As a preferred embodiment, grooves are provided at the bottom of both sides of the beam body; multiple sleeve structures and grooves are provided, and all are equidistant. Both the sleeve structures and grooves are used for fixed connection with the base plate for battery module mounting, thereby improving installation stability.

[0009] As a preferred embodiment, the beam body has a hollow plate-like structure; the hollow plate-like structure is formed by a first side plate and a second side plate arranged in parallel, and a top plate and a bottom plate arranged in parallel; a reinforcing plate connects the first side plate and the second side plate. The beam body serves to limit and fix the battery module. The hollow plate-like structure effectively reduces the weight of the beam, and the installation of the reinforcing plate effectively improves the overall bending and torsional stiffness of the beam body.

[0010] As a preferred embodiment, the beam body, sleeve structure, and reinforcing plate are integrally formed metal or composite material structures. This integrally formed structure reduces the number of parts, improves assembly efficiency, reduces welding processes, simplifies the assembly process, and reduces weight.

[0011] As a preferred embodiment, a conformal thermal pad is disposed inside the beam body, and the conformal thermal pad is tightly fitted to the inner surface of the beam body. The thermal pad is made of a flexible thermally conductive material, which can fit tightly to the inner surface of the beam body to achieve efficient heat conduction and diffusion. The conformal thermal pad can be locally shaped according to the arrangement of the internal reinforcing plates of the beam body to enhance the thermal conduction efficiency of the module beam structure, thereby improving the heat dissipation efficiency of the battery module.

[0012] A battery pack structure includes a battery module, a mounting base plate for mounting the battery module, castings fixedly disposed at both ends of the mounting base plate and parallel to each other, and a cover covering the top and sides of the battery module. The castings are perpendicular to the mounting base plate. The structure is characterized by further including module beam structures perpendicularly disposed on the mounting base plate; the module beam structures are the aforementioned module beam structures; there are two or more module beam structures; the mounting base plate has base plate connection holes, and sleeve structures at the bottom of the module beam structures are inserted into the base plate connection holes to fix the module beam structures to the mounting base plate; the battery module is disposed between adjacent module beam structures, and the battery module is limited and fixed by a pre-tightening force applied between adjacent module beam structures. By fixing the battery module and battery cells with pre-tightening force, the use of steel cable ties, screws, and connecting pieces is eliminated, reducing weight, the number of parts, and the assembly process.

[0013] As a preferred embodiment, the sleeve structure is fixed to the connection hole of the base plate by interference fit and / or welding. The interference fit and / or welding connection between the sleeve structure and the connection hole of the base plate strengthens the connection between the modular beam structure and the mounting base plate. The sleeve structure being open at the bottom further reduces the weight of the modular beam structure.

[0014] As a preferred embodiment, the battery module is fixedly mounted on the mounting base plate; end plates are fixedly connected to both ends of the battery module, and both ends of the battery module abut against the module beam structure through the end plates; the end plates are parallel to the casting and the module beam structure. One side of the end plate is fitted to the module beam structure, and the other side is fixedly connected to the battery module.

[0015] Furthermore, the end plate is an integral structure; the end plate and the battery module are fixed together by adhesive bonding.

[0016] Furthermore, the bottom of the battery module is glued and fixed to the mounting base plate.

[0017] As a preferred embodiment, the distance reserved between adjacent module beam structures is less than the total length of the battery module and its two end plates.

[0018] Compared with the prior art, the beneficial effects of this utility model are as follows:

[0019] This invention provides a module beam structure and a battery pack structure for battery modules. Compared with existing solutions, the casing weight is lower, and the battery pack structure has better structural strength: the modal gain is 2.45% higher than existing structures, achieving a balance between structural strength and lightweight design. The battery pack structure of this invention is structurally simple, low-cost, has fewer components, and is easy to manufacture. Attached Figure Description

[0020] Figure 1 and Figure 2 This is a three-dimensional structural diagram of the modular beam structure in this utility model;

[0021] Figure 3 This is a side view of the modular beam structure in this utility model;

[0022] Figure 4 This is a three-dimensional structural diagram of the battery pack structure in this utility model;

[0023] Figure 5 This is a schematic diagram of the mounting base plate in this utility model;

[0024] Figure 6 This is a schematic left-side cross-sectional view of the mounting base plate in this utility model;

[0025] Figure 7This is a three-dimensional structural diagram of the internal structure of the battery pack in this utility model (excluding the battery module and control components);

[0026] Figure 8 This is a schematic diagram of the internal structure of the battery pack in this utility model.

[0027] Figure 9 The diagram shows the modal analysis results of the battery pack structure in this utility model.

[0028] Figure 10 The diagram shows the modal analysis results of the battery pack structure in the prior art.

[0029] Figure 11 The figure shows the simulation results of the expansion force of the battery pack structure in this utility model;

[0030] In the diagram: 1. Module beam structure; 101. First module beam; 102. Second module beam; 103. Third module beam; 2. Battery module; 3. Mounting base plate; 4. Casting; 5. Box cover; 6. End plate; 7. Control electrical components; 8. Washer.

[0031] The modular beam structure 1 includes: 11, beam body (111, first side plate; 112, second side plate; 113, top plate; 114, bottom plate; 115, groove); 12, sleeve structure (121, sleeve hole); 13, reinforcing plate; 14, conformal thermal pad;

[0032] Mounting base plate 3 includes: 31, base plate connecting strip (311, base plate connecting hole); 32, coolant flow channel; 33, first base plate; 34, second base plate; 35, friction stir weld bead; 36, first blocking strip; 37, second blocking strip; 38, orifice; 39, bolt hole;

[0033] The lid 5 includes: 51, the top surface of the lid; 52, the side surface of the lid. Detailed Implementation

[0034] To better explain this utility model, the main contents of this utility model are further illustrated below with reference to the accompanying drawings and specific embodiments, but the contents of this utility model are not limited to the following embodiments.

[0035] Example 1

[0036] like Figures 1-2As shown, this utility model discloses a module beam structure 1 for a battery module, used to fix a battery module 2 within a battery pack structure. The module beam structure 1 includes a beam body 11, a sleeve structure 12, a reinforcing plate 13, and a conformal thermal conductive pad 14. Four downwardly protruding sleeve structures 12 are fixedly disposed at the bottom of the beam body 11, and are equidistantly arranged. The reinforcing plate 13 is fixedly disposed inside the beam body 11. The conformal thermal conductive pad 14 is disposed inside the beam body 11 and is tightly fitted to its inner surface and the surface of the reinforcing plate 13.

[0037] Specifically, the beam body 11 has a hollow plate-like structure. For example... Figure 3 As shown, the hollow plate-like structure is formed by a first side plate 111 and a second side plate 112 arranged in parallel, and a top plate 113 and a bottom plate 114 arranged in parallel. Grooves 115 are provided at the bottom of the two side plates of the beam body 11. These grooves 115 are used for welding to the mounting base plate 3 of the battery module 2 during assembly. There are eight grooves 115, with four located at equal intervals on the bottom of each side of the beam body 11.

[0038] like Figure 2 As shown, a sleeve hole 121 is provided in the middle of the bottom of the sleeve structure 12, which can further reduce the weight of the module beam structure 1. The sleeve structure 12 is used to make an interference fit and / or welded connection with the base plate connection hole 311 on the mounting base plate 3 when installing the battery module 2, and together with the groove 115, fixes the module beam structure 1 to the mounting base plate 3 of the battery module 2. The sleeve structure 12 can be interference fitted or welded to the mounting base plate 3, or the sleeve structure 12 can be fixedly connected to the mounting base plate 3 by a combination of interference fit and welding.

[0039] A reinforcing plate 13 is disposed between the first side plate 111 and the second side plate 112, connecting the first side plate 111 and the second side plate 112 to improve the overall bending and torsional stiffness of the beam body 11. The reinforcing plate 13 is inclined, and the adjacent reinforcing plates 13 are arranged in a V-shape.

[0040] The beam body 11, sleeve structure 12, and reinforcing plate 13 are integrally formed metal or composite material structures.

[0041] The conformal thermal pad 14 is made of flexible thermal conductive material and can be closely attached to the inner surface of the beam body 11 and the surface of the reinforcing plate 13 to achieve efficient heat conduction and diffusion.

[0042] Example 2

[0043] like Figures 4-9As shown, a battery pack structure of this utility model includes a cubic structure formed by a cover 5, two castings 4, and a mounting base plate 3 fixedly connected together, and a battery module 2, a module beam structure 1 (as in Embodiment 1), an end plate 6, and control electrical components 7 located inside the cubic structure. In this cubic structure, the cover 5 is located at the top and both sides, the two castings 4 are respectively placed at both ends, and the mounting base plate 3 is located at the bottom. The castings 4, the module beam structure 1, and the end plate 6 are fixed parallel to each other on the mounting base plate 3.

[0044] The mounting base plate 3 is used to fix the battery module 2. The casting 4 is fixedly set at both ends of the mounting base plate 3 and is parallel to each other. The cover 5 covers the top and sides of the battery module 2. The module beam structure 1 is vertically set on the mounting base plate 3. The mounting base plate 3 is provided with a base plate connection hole 311. The sleeve structure 12 at the bottom of the module beam structure 1 is inserted into the base plate connection hole 311 to fix the module beam structure 1 on the mounting base plate 3. The module beam structure 1 limits the position of the battery module 2. The end plate 6 is vertically set on the mounting base plate 3 and fixedly installed at both ends of the battery module 2. One side of the end plate 6 is attached to the module beam structure 1, and the other side is fixedly connected to the battery module 2.

[0045] Specifically, such as Figure 4 As shown, the box cover 5 includes a top surface 51 and two side surfaces 52 that are fixedly connected to the top surface 51 and arranged parallel to each other. The two ends of the top surface 51 are respectively fixedly connected to two castings 4 by bolts; the two ends of the side surfaces 52 are respectively fixedly connected to the castings 4 by bolts; and the bottom of the side surfaces 52 are fixedly connected to the mounting base plate 3 by bolts. The box cover 5 is a one-piece molded structure.

[0046] like Figure 5 and Figure 6 As shown, the mounting base plate 3 is a liquid-cooled base plate with a coolant flow channel 32 inside. The coolant flow channel 32 is arranged in a serpentine shape to contain the coolant and provide a flow channel for the coolant to cool the battery module 2.

[0047] The mounting base plate 3 includes two identical first base plates 33 and second base plates 34. The first base plate 33 and the second base plate 34 are spliced ​​together and fixed by friction stir welding, thereby forming a friction stir weld bead 35 on the mounting base plate 3. A base plate connecting strip 31 is fixedly installed inside the mounting base plate 3. The length direction of the base plate connecting strip 31 is parallel to the length direction of the mounting base plate 3, and a serpentine turning space for coolant flow channels 32 is reserved between the two ends of the base plate connecting strip 31 and the two ends of the mounting base plate 3. The number of base plate connecting strips 31 is the same as the number of sleeve structures 12 on a module beam structure 1, with four strips evenly distributed in the width direction of the mounting base plate 3. Base plate connecting holes 311 are provided on the base plate connecting strips 31 for interference fit and / or welding connection with the sleeve structures 12 at the bottom of the module beam structure 1, realizing a fixed connection between the module beam structure 1 and the mounting base plate 3. A first blocking strip 36 and a second blocking strip 37 are respectively provided at the two ends of the mounting base plate 3 to prevent coolant leakage. An orifice 38 is provided on the upper inner surface of one end of the first base plate 33 and the second base plate 34 respectively; the two orifices 38 are respectively connected to the coolant flow channel 32, one of which serves as the coolant inlet and the other as the coolant outlet. The path of the coolant flow channel 32 is as follows: starting from the coolant inlet, it extends along the width direction of the mounting base plate 3 towards the edge of the mounting base plate 3 away from the coolant outlet; then it bends and turns to extend along the length direction of the mounting base plate 3 to the inner side of the other end away from the coolant inlet; it bends again and continues to extend along the length direction of the mounting base plate 3 towards the end where the coolant inlet is located; this bending is repeated to form multiple parallel flow channel segments extending along the length direction of the mounting base plate 3 until it extends to the edge of the mounting base plate 3 adjacent to the coolant outlet and to the inner side of the end where the coolant outlet is located on the mounting base plate 3; finally, it bends and turns to extend along the width direction of the mounting base plate 3 and connects with the coolant outlet. Bolt holes 39 are provided on both sides of the mounting base plate 3 for securing the box cover 5 to the mounting base plate 3 with bolts.

[0048] like Figure 7 and Figure 8As shown, the modular beam structure 1 is fixedly mounted on the mounting base plate 3 and is perpendicular to the mounting base plate 3. There are three modular beam structures 1: a first modular beam 101, a second modular beam 102, and a third modular beam 103. The first modular beam 101 and the third modular beam 103 are located inside the castings 4 at both ends of the mounting base plate 3, while the second modular beam 102 is located in the middle of the mounting base plate 3. The grooves 115 on the bottom sides of the beam body 11 are fixedly connected to the mounting base plate 3 by welding. The sleeve structure 12 at the bottom of the modular beam structure 1 is inserted into the bottom plate connection hole 311 of the mounting base plate 3 and fixed by interference fit and / or welding, thus fixing the modular beam structure 1 to the mounting base plate 3. In this embodiment, the sleeve structure 12 is fixed to the bottom plate connection hole 311 by an interference fit. A washer 8 is sleeved on the outside of the sleeve structure 12. The washer 8 is placed between the contact surface of the module beam structure 1 and the mounting base plate 3 to protect the contact surface of the module beam structure 1 and the mounting base plate 3 of the battery module 2, distribute pressure, and prevent loosening.

[0049] like Figure 7 As shown, there are two castings 4, which are respectively vertically mounted at both ends of the mounting base plate 3 and parallel to each other, with their bottoms welded to the mounting base plate 3. Bolt holes 39 are evenly provided on the top and sides of the castings 4 so that the box cover 5 can be bolted to the castings 4. The castings 4 and the mounting base plate 3 are fixedly connected to the box cover 5 together by bolts.

[0050] like Figure 8 As shown, the control device 7 is located inside the casting 4 and is fixedly installed between the module beam structure 103 and the casting 4 at one end of the mounting base plate 3. The control device 7 is locked to the side wall of the module beam structure 103 by locking bolts or welded to the mounting base plate 3, and is used to detect the power of the battery module 2.

[0051] like Figure 8 As shown, the bottom of the battery module 2 is glued and fixed to the mounting base plate 3. Two battery modules 2 are provided, located between adjacent module beam structures 1, and abut against the module beam structures 1 via end plates 6. The module beam structures 1 provide limiting and fixing, and the adjacent module beam structures 1 apply a pre-tightening force to the battery modules 2 by pressing them together. The end plates 6 are an integral structure, with four in total, respectively located at both ends of the two battery modules 2, and are glued and fixed to the battery modules 2. One side of the end plate 6 is attached and fixed to the first side plate 111 or the second side plate 112 of the module beam structure 1, and the other side is glued to the battery module 2.

[0052] The top of the end plate 6 is flush with the top of the battery module 2; the top of the module beam structure 1 is slightly lower than the top of the battery module 2, by 20mm. The reserved distance between adjacent module beam structures 1 is less than the total length of the battery module 2 and its two end plates 6, so that the module beam structures 1 can compress the battery module 2 to form a pre-tightening force, keeping the battery module 2 installed stably; the reserved distance between adjacent module beam structures 1 is 1mm smaller than the total length of the battery module 2 and the end plate 6.

[0053] Modal analysis was performed on the above-described battery pack structure and on the existing battery pack structure, which uses profiled liquid-cooled base plates, modular beams, die-cast metal end plates, connecting pieces, steel straps, castings, and sleeves. The modal analysis results are as follows: Figure 9 and Figure 10 As shown in the figure. The results show that the overall Z-axis dominant frequency of the battery pack in this invention can reach 76 Hz, and the modal gain is 2.45% compared with the existing battery packs of the same mass and energy density. In addition, the expansion force simulation test of the battery pack structure in this invention was carried out, and the test results are as follows. Figure 11 As shown, the three-row modules can withstand an expansion force of 94KN, and a single module can withstand an expansion force of up to 31KN, achieving battery pack lightweighting while meeting certain structural strength requirements. Currently, multi-component welded enclosures on the market have low rigidity. This invention adopts an integrated modular beam structure to enhance the overall rigidity of the enclosure, which is beneficial for modal improvement. The interference fit or welding connection between the sleeve structure 12 of the modular beam structure 1 and the bottom plate connection hole 311 of the mounting base plate 3 greatly enhances the bending and torsional rigidity of the enclosure.

[0054] This utility model proposes a module beam structure for battery modules and a battery pack structure including the module beam structure. By optimizing the connection structure between the module beam and the base plate and end plate, it has the following beneficial effects:

[0055] In this utility model, the module beam structure is provided with a sleeve structure and groove, and is fixed to the base plate by interference fit and / or welding, which effectively ensures the connection strength and structural stability between the module and the base plate, and enhances the overall load-bearing performance of the battery box under vibration, impact and other working conditions.

[0056] In this invention, the sleeve structure and groove are arranged at equal intervals, which makes the module beam structure and the base plate accurately aligned and quick to install. This simplifies the process while ensuring the consistency of batch assembly and reducing assembly errors.

[0057] In this invention, a conformal thermal pad is installed inside the module beam, which is closely attached to its inner wall. This effectively improves the heat conduction efficiency generated during the operation of the battery module, reduces local temperature rise, improves heat dissipation, and ensures the thermal safety of the battery cell.

[0058] The main body of this utility model is a hollow plate structure, which reduces weight, but it is reinforced with internal reinforcing plates to further improve its structural rigidity, avoid structural deformation or fatigue during long-term use, and extend its service life.

[0059] The modular beam structure of this utility model can be manufactured using one-piece molded metal or composite materials, adapting to different strength and quality requirements, simplifying the types of parts, reducing production costs, and facilitating mass standardized manufacturing.

[0060] In this utility model, the module beam structure and end plate form a stable support at both ends of the battery module, and the reserved gap between adjacent module beam structures is slightly smaller than the length of the battery cell. The battery cell is secured by the pre-tightening force generated during assembly, which effectively prevents the battery cell from loosening or shifting due to vibration and improves the overall operational safety of the battery pack.

[0061] This utility model, by adopting the modular beam structure in the battery pack structure, can be flexibly arranged according to the design requirements of different battery modules, and can be combined with castings and end plates to effectively control the overall weight and meet the lightweight requirements of new energy vehicles.

[0062] All other unspecified parts belong to the prior art.

Claims

1. A module beam structure for a battery module, characterized in that: It includes a beam body (11); the bottom of the beam body (11) is provided with a downward protruding sleeve structure (12); the beam body (11) is a hollow structure and is provided with a reinforcing plate (13) inside.

2. The modular beam structure according to claim 1, characterized in that: The bottom of both sides of the beam body (11) is provided with grooves (115); the sleeve structure (12) and the grooves (115) are provided with multiple grooves.

3. The modular beam structure according to claim 1, characterized in that: The beam body (11) has a hollow plate structure; the hollow plate structure is formed by a first side plate (111) and a second side plate (112) arranged in parallel, a top plate (113) and a bottom plate (114) arranged in parallel; the reinforcing plate (13) is connected between the first side plate (111) and the second side plate (112).

4. The modular beam structure according to claim 1, characterized in that: The beam body (11), sleeve structure (12), and reinforcing plate (13) are integrally formed structures.

5. The modular beam structure according to any one of claims 1 to 4, characterized in that: The beam body (11) is provided with a conformal heat-conducting pad (14) inside, and the conformal heat-conducting pad (14) is closely attached to the inner surface of the beam body (11).

6. A battery pack structure, comprising a battery module (2), a mounting base plate (3) for mounting the battery module (2), castings (4) fixedly disposed at both ends of the mounting base plate (3) and parallel to each other, and a cover (5) covering the top and sides of the battery module (2), wherein the castings (4) are disposed perpendicular to the mounting base plate (3), characterized in that: It also includes a module beam structure (1) vertically arranged on the mounting base plate (3); the module beam structure (1) is the module beam structure (1) according to any one of claims 1 to 5; there are two or more module beam structures (1); the mounting base plate (3) is provided with a base plate connection hole (311), and the sleeve structure (12) at the bottom of the module beam structure (1) is inserted into the base plate connection hole (311) to fix the module beam structure (1) on the mounting base plate (3); the battery module (2) is arranged between adjacent module beam structures (1), and the battery module (2) is limited and fixed by the preload applied between adjacent module beam structures (1).

7. The battery pack structure according to claim 6, characterized in that: The sleeve structure (12) is fixed to the bottom plate connection hole (311) by interference fit and / or welding.

8. The battery pack structure according to claim 6 or 7, characterized in that: The battery module (2) is fixedly mounted on the mounting base plate (3); the two ends of the battery module (2) are fixedly connected to end plates (6), and the two ends of the battery module (2) abut against the module beam structure (1) through the end plates (6); the end plates (6) are parallel to the casting (4) and the module beam structure (1).

9. The battery pack structure according to claim 8, characterized in that: The end plate (6) is an integral structure; the end plate (6) and the battery module (2) are fixed by adhesive bonding.

10. The battery pack structure according to claim 8, characterized in that: The distance between adjacent module beam structures (1) is less than the total length of the battery module (2) and its two end plates (6).

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