Battery pack end plate, battery fixing assembly and battery pack

Abstract

The utility model belongs to battery pack group technology field, specifically disclose a kind of battery pack end plate, battery fixed assembly and battery pack, including battery end plate, liquid cooling plate group, fixed beam frame and battery module, wherein, battery end plate includes end plate body and the connecting branch plate integrally formed in the top of end plate body, the connecting position of end plate body and connecting branch plate is formed with the transition section of inclination by continuous bending, transition section is outwardly inclined to be arranged to make connecting branch plate and end plate body constitute dislocation structure;Compared with prior art, the battery pack end plate, battery fixed assembly and battery pack involved in the present application, by the design of the inclined transition section between the end plate body and the connecting branch plate, in combination with the coordinated structure of the buffer cavity, the liquid cooling plate group and the fixed beam frame, effectively dispersing and absorbing the battery expansion force, reducing the risk of stress concentration, with the advantages of improving the overall structural stability and prolonging the service life.

Description

Technical Field

[0001] This utility model belongs to the field of battery pack assembly technology, and particularly relates to a battery pack end plate, a battery fixing component, and a battery pack. Background Technology

[0002] With the continued development of the electric motorcycle market, pouch lithium-ion batteries have been widely used in this field due to their lightweight, high energy density, excellent safety performance, long cycle life, and large capacity. Early products, due to lower requirements for power and rate performance, typically only required a single battery module and natural cooling to meet usage needs. However, as users' expectations for range and power performance have increased, modern battery pack designs have gradually shifted towards using multiple battery modules connected in series to improve overall power output and introducing liquid cooling systems for efficient thermal management. This increased complexity of the multi-module liquid-cooled structure significantly increases the difficulty of battery pack assembly and structural stability.

[0003] In existing technologies, battery packs typically employ a flat end plate and side plate connected by welding or screws to construct the battery compartment, housing a cell assembly composed of multiple cells. However, pouch cells generate continuous expansion forces during charge-discharge cycles, which are almost entirely concentrated on the planar area of ​​the end plate. Due to the high rigidity of traditional flat end plates, their deformation capacity is extremely limited, absorbing only a small portion of the expansion force. Consequently, the vast majority of the expansion force is directly transferred to the weld joints of the side plates. When the accumulated expansion force exceeds the strength limit of the weld material, the weld is highly susceptible to tearing failure, leading to battery module structural collapse, safety hazards, and functional interruptions. This problem is particularly prominent in high-energy-density battery pack applications, severely restricting the reliability and lifespan of the battery system.

[0004] To address the aforementioned issues, existing technologies urgently need improvement. Utility Model Content

[0005] The purpose of this utility model is to provide a battery pack end plate, a battery fixing assembly, and a battery pack. By setting an inclined transition section, the end plate can better fit the battery module and the fixing beam after installation, effectively improving the fixing effect of the battery module and the overall structural strength of the battery pack. At the same time, the setting of multiple buffer cavities can effectively absorb the expansion force generated during battery charging and discharging, reduce stress concentration, and thus improve the reliability and service life of the overall battery pack structure.

[0006] To achieve the above objectives, the technical solution of this utility model is as follows: a battery pack end plate, comprising an end plate body and a connecting support plate integrally formed on the top of the end plate body, wherein the connection position between the end plate body and the connecting support plate is formed by continuous bending to create an inclined transition section, and the transition section is inclined outward so that the connecting support plate and the end plate body form a misaligned structure.

[0007] Furthermore, the end plate body is also provided with a buffer cavity, which extends vertically upward from the bottom end of the end plate body to the transition section. Multiple buffer cavities are provided, and the multiple buffer cavities are spaced apart laterally along the end plate body.

[0008] Furthermore, the transition section forms an angle α with the vertical direction, and the angle α is 20°-25°.

[0009] Furthermore, the end plate body protrudes outward to form the buffer cavity, the depth of which is 1.5-2.0 mm.

[0010] Furthermore, this utility model also discloses a battery fixing assembly, including the aforementioned battery pack end plate, and further including a fixing beam and a liquid cooling plate assembly. The liquid cooling plate assembly includes a horizontally arranged liquid cooling base plate. The end plate bodies are two parallel end plates, which are respectively disposed at both ends of the length direction of the liquid cooling base plate. The bottoms of the two end plate bodies are respectively detachably connected to both ends of the length direction of the liquid cooling base plate. The fixing beam is disposed above the liquid cooling base plate, and both ends of the fixing beam are detachably connected to the connecting support plates corresponding to the two end plate bodies.

[0011] Furthermore, the liquid-cooled plate assembly also includes multiple vertically arranged liquid-cooled baffles, which are arranged in parallel between the two end plate bodies. The bottom of the liquid-cooled baffles is connected to the liquid-cooled base plate, and the top of the liquid-cooled baffles is connected to the fixed beam frame.

[0012] Furthermore, connecting plates are installed at both ends of the fixed beam frame along its length. The connecting plates are attached to the connecting support plates and connected in a detachable manner, so that the fixed beam frame and the end plate body are connected. The connecting plates protrude outward to form multiple limiting bosses. The connecting support plates are provided with multiple limiting grooves corresponding to the multiple limiting bosses. The limiting bosses are inserted into the limiting grooves when the connecting plates and the connecting support plates are connected.

[0013] Furthermore, the two ends of the connecting support plate are provided with rectangular overlapping notches, and the two ends of the connecting plate protrude outward to form overlapping flanges. When the connecting plate and the connecting support plate are connected, the overlapping flanges overlap and fit against the overlapping flanges.

[0014] Furthermore, this utility model also discloses a battery pack, including the battery fixing assembly as described above, and also including a battery module. The battery module is disposed between the end plate body and the adjacent liquid cooling partition, and between any adjacent liquid cooling partitions.

[0015] The beneficial effects of this technical solution are as follows:

[0016] This utility model discloses a battery pack end plate, a battery fixing assembly, and a battery pack. By setting an inclined transition section, the end plate can better fit the battery module and the fixing beam after installation, effectively improving the fixing effect of the battery module and the overall structural strength of the battery pack. At the same time, the setting of multiple buffer cavities can effectively absorb the expansion force generated during battery charging and discharging, reduce stress concentration, improve the structural stability and electrical safety of the battery pack, and avoid battery module failure.

[0017] Compared with the prior art, the battery pack end plate, battery fixing assembly and battery pack involved in this application, through the design of the inclined transition section between the end plate body and the connecting support plate, combined with the synergistic structure of the buffer cavity, liquid cooling plate assembly and fixed beam frame, effectively disperse and absorb the battery expansion force, reduce the risk of stress concentration, and have the advantages of improving the overall structural stability and extending the service life. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the structure of the battery pack end plate of this utility model;

[0019] Figure 2 This is a front view of the battery pack end plate of this utility model;

[0020] Figure 3 for Figure 2 Sectional view at point AA;

[0021] Figure 4 for Figure 3 A magnified view of a section at point B in the middle;

[0022] Figure 5 This is a schematic diagram of the battery pack structure of this utility model;

[0023] Figure 6 for Figure 5 A magnified view of a section at point C. Detailed Implementation

[0024] The following detailed description illustrates the specific implementation method:

[0025] The reference numerals in the accompanying drawings include: end plate body 1, connecting support plate 2, buffer cavity 3, transition section 4, limiting groove 5, overlapping notch 6, fixed beam frame 7, connecting plate 8, overlapping flange 801, limiting boss 802, liquid cooling base plate 9, liquid cooling partition 10, battery module 11.

[0026] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of the present utility model. Unless otherwise specified, "outward" in this embodiment refers to the direction away from the battery pack itself after the battery pack is installed and formed, and "inward" refers to the direction towards the battery pack itself. This is understandable to those skilled in the art and will not be elaborated here.

[0027] The basic implementation examples are as follows: Figures 1-4 The diagram shows a battery pack end plate, comprising an end plate body 1 and a connecting support plate 2 integrally formed on the top of the end plate body 1. The connection point between the end plate body 1 and the connecting support plate 2 is formed by continuous bending to create an inclined transition section 4. The transition section 4 is inclined outwards to create a misaligned structure between the connecting support plate 2 and the end plate body 1. The end plate body 1 serves as the main load-bearing component for supporting and fixing the battery module 11, and can be manufactured by methods such as metal sheet stamping, casting, or composite material molding. The connecting support plate 2, as a key component for connecting to external structures, can be integrally formed with the end plate body 1 through welding or other mechanical connections. The transition section 4 is achieved through multiple bends, primarily to create a misalignment between the end plate body 1 and the connecting support plate 2. After installation, the end plate body 1 is closer to the battery module 11 relative to the connecting support plate 2, maximizing the contact area between the battery pack end plate as a whole, the battery module 11, and the fixed beam 7. This increases the overall fixation and structural strength of the battery pack. Simultaneously, this bend-misaligned structure also effectively disperses and buffers forces, allowing the expansion force generated by the battery module 11 to be dispersed along a specific direction through the inclined design of the transition section 4, avoiding force concentration in the vertical direction and reducing stress concentration. Furthermore, the misaligned structure optimizes the overall stiffness distribution of the end plate, enabling it to deform synergistically under stress, transforming the expansion force into a flexible buffer within the structure rather than directly acting on the fixed weld, ultimately ensuring the battery pack maintains structural integrity during long-term use.

[0028] In this embodiment, the end plate body 1 is further provided with a buffer cavity 3. The buffer cavity 3 extends vertically upward from the bottom end of the end plate body 1 to the transition section 4. Multiple buffer cavities 3 are provided, spaced laterally along the end plate body 1. Specifically, the buffer cavity 3 refers to a cavity structure with a certain depth and shape formed within the end plate body 1, which can be achieved by stamping, casting, or machining. The purpose of the buffer cavity 3 is to absorb the expansion force generated on the side of the battery module 11 under battery pack operating conditions by providing elastic deformation space, thereby improving the structural stability and electrical safety of the battery pack and preventing battery module 11 failure. The multiple buffer cavities 3 are distributed laterally along the end plate body 1. This design can disperse the expansion force to multiple independent areas in the width direction of the end plate, preventing stress accumulation at a single location, thus enhancing the overall structural stability. In this embodiment, two buffer cavities 3 are preferably provided. By integrating the buffer cavity 3 structure on the end plate body 1, the end plate's ability to absorb the cell expansion force is significantly improved. The buffer cavity 3 extends from the bottom of the end plate body 1 to the transition section 4, ensuring that the buffering effect covers the entire height path from the bottom fixed area to the transition area of ​​the connecting support plate 2, preventing sudden changes in local stress. In addition, the lateral spacing of multiple buffer cavities 3 not only evens out the force distribution, but also gives the originally rigid end plate a certain elastic deformation characteristic. When the cell expands, the buffer cavity 3 can consume some energy through its own deformation.

[0029] In this embodiment, the transition section 4 forms an angle α with the vertical direction, and the angle α is 20°-25°. Specifically, the angle α refers to the tilt angle of the transition section 4 relative to the vertical direction. The purpose of limiting the angle α is to optimize the mechanical response of the end plate during battery expansion, ensure the stress distribution at the bending point, and avoid structural failure.

[0030] In this embodiment, the end plate body 1 protrudes outward to form the buffer cavity 3, the depth of which is 1.5-2.0 mm. Specifically, the buffer cavity 3 refers to a structure with accommodating space formed by the outward protrusion of a local material of the end plate body 1, which can be achieved by stamping or machining. The depth range of the buffer cavity 3 is set to 1.5-2.0 mm. This specific range is selected based on a comprehensive consideration of multiple factors such as the elastic modulus of the end plate material and the dynamic characteristics of the cell expansion force. The purpose is to ensure that the buffer cavity 3 can provide sufficient deformation space to absorb expansion energy while maintaining the local strength of the end plate, avoiding failure due to excessive structural weakness caused by excessive depth. On this basis, the design of the buffer cavity 3, combined with the staggered structure of the end plate body 1 and the connecting support plate 2, further enhances the overall deformation resistance of the end plate. The continuous bending transition section 4 of the end plate body 1 and the buffer cavity 3 work together to form a multi-layered energy absorption mechanism, effectively addressing the expansion force problem during the use of the soft-pack battery pack.

[0031] This embodiment also discloses a battery fixing assembly, including the aforementioned battery pack end plate, a fixing beam 7, and a liquid cooling plate assembly. The liquid cooling plate assembly includes a horizontally arranged liquid cooling base plate 9. The end plate bodies 1 are two parallel ones, and the two end plate bodies 1 are respectively disposed at both ends of the length direction of the liquid cooling base plate 9. The bottoms of the two end plate bodies 1 are respectively detachably connected to the two ends of the length direction of the liquid cooling base plate 9. The fixing beam 7 is disposed above the liquid cooling base plate 9, and the two ends of the fixing beam 7 are respectively detachably connected to the connecting support plates 2 corresponding to the two end plate bodies 1. Specifically, the liquid-cooled base plate 9, as the main component of the bottom support foundation and the cooling components of the battery pack, has battery pack end plates at both ends. Multiple oblong holes are formed at the bottom of the battery pack end plates, which are detachably fixed to the liquid-cooled base plate 9 via bolts. The connecting support plate 2 also has multiple oblong holes. After the connecting support plate 2 is attached to the connecting plate 8, it is fixed with bolts, rivets, and other fasteners, thus connecting the fixing beam 7 to the two battery pack end plates. Thus, the battery pack end plates, liquid-cooled base plate 9, and fixing beam 7 constitute the external frame and main load-bearing components for fixing the battery module 11. This collaborative constraint mechanism of the battery pack end plates, liquid-cooled base plate 9, and fixing beam 7 effectively disperses the impact of the expansion force of the battery module 11 on the overall fixing structure, while also ensuring the cooling effect of the battery module 11.

[0032] In this embodiment, the liquid-cooled plate assembly further includes multiple vertically arranged liquid-cooled partitions 10. These partitions 10 are arranged parallel to each other between the two end plate bodies 1. The bottom of each liquid-cooled partition 10 is connected to the liquid-cooled base plate 9, and the top of each partition 10 is connected to the fixed beam frame 7. The liquid-cooled partition 10 is a structural component used to separate the battery modules 11 and provide support. Its main function is to separate the outer frame formed by the battery pack end plates, the liquid-cooled base plate 9, and the fixed beam frame 7, allowing each battery module 11 to have an independent installation compartment. Simultaneously, the synergistic effect of the multiple liquid-cooled partitions 10 and the liquid-cooled base plate 9 effectively cools the battery modules 11 during operation, further improving the overall thermal management capability of the battery pack.

[0033] In this embodiment, connecting plates 8 are respectively installed at both ends of the fixed beam frame 7 along its length. The connecting plates 8 are closely attached to the connecting support plate 2 and are detachably connected, so that the fixed beam frame 7 and the end plate body 1 are connected. The connecting plates 8 protrude outward to form multiple limiting bosses 802. The connecting support plate 2 is provided with multiple limiting grooves 5 corresponding to the multiple limiting bosses 802. The limiting bosses 802 are inserted into the limiting grooves 5 when the connecting plates 8 and the connecting support plate 2 are connected. Specifically, the connecting plate 8 is an intermediate component used to connect the fixed beam frame 7 and the connecting support plate 2. It can be made by stamping or injection molding of metal sheet. In practical applications, the design of the connecting plate 8 needs to take into account both strength and ease of assembly. Its purpose is to provide a stable connection base while facilitating subsequent maintenance and disassembly operations. The limiting boss 802 can be understood as a positioning structure on the connecting plate 8, formed by a protrusion of local material. This can be achieved through stamping, injection molding, or welding of additional components, and its purpose is to provide precise positioning and enhance the shear resistance of the connection. Furthermore, the limiting groove 5 refers to a recessed structure on the connecting support plate 2 that matches the limiting boss 802. This recess can be achieved through machining, stamping, or injection molding, and its purpose is to cooperate with the limiting boss 802 to achieve precise positioning and distribute stress. As a preferred embodiment, the outermost point of the buffer cavity 3 does not extend beyond the bottom plane of the limiting groove 5, which improves the efficiency of assembling the battery module 11 into the battery pack housing. Thus, through the close connection between the connecting plate 8 and the connecting support plate 2, a stable basic assembly frame is constructed. This design not only facilitates quick assembly and disassembly but also effectively absorbs the impact of external vibrations. Multiple outwardly protruding limiting bosses 802 on the connecting plate 8 naturally guide the insertion action during assembly, ensuring precise alignment between the limiting bosses 802 and the limiting grooves 5, thus avoiding errors that may be introduced by manual adjustment. Once the limiting bosses 802 are inserted into the limiting grooves 5, a mechanical interlocking relationship is formed. This insertion method constrains the connection point in both the lateral and longitudinal directions, preventing relative displacement caused by battery expansion forces or external vibrations. Furthermore, the cooperation between the limiting bosses 802 and the limiting grooves 5 also evenly disperses the stress generated by battery expansion, avoiding slippage caused by localized stress concentration, thereby significantly improving the tightness of the connection and the reliability of the overall structure. Through the above design, the connection stability between the fixed beam frame 7 and the end plate body 1 is effectively guaranteed, thereby improving the overall performance and long-term durability of the battery fixing assembly.

[0034] In this embodiment, rectangular overlapping notches 6 are provided at both ends of the connecting support plate, and the corresponding two ends of the connecting plate 8 protrude outward to form overlapping flanges 801. The overlapping flanges 801 overlap and fit against the connecting plate 8 when it is connected to the connecting support plate 2. Specifically, the overlapping notch 6 refers to a rectangular notch structure with a regular geometric shape, which can be realized by machining, stamping, or casting. Its purpose is to provide a precise positioning reference and limiting function for the connection. The overlapping flanges 801 are protruding structures located at both ends of the end faces of the fixed ends, which can be formed by local thickening or welding of additional parts. In the installed state, the two notch edges of the overlapping notch 6 can respectively abut against the corresponding side and bottom surfaces of the overlapping flanges 801, preventing displacement of the fixed beam and further improving the overall structural strength of the battery pack. At the same time, this structure improves the space utilization and energy density of the battery pack, and can serve as a stress relief point, ensuring the flatness of the bent part after it is fixed to the fixed beam.

[0035] like Figures 5-6 As shown, this embodiment also discloses a battery pack, including the battery fixing assembly as described above, and a battery module 11. Battery modules 11 are disposed between the end plate body 1 and the adjacent liquid-cooled partition 10, and between any adjacent liquid-cooled partitions 10. Specifically, after assembly, the sidewall of the corresponding battery module 11 is attached to the liquid-cooled partition or the end plate body 1. Thus, through the design of the inclined transition section 4 between the end plate body 1 and the connecting support plate 2, combined with the synergistic structure of the buffer cavity 3, the liquid-cooled plate assembly, and the fixed beam frame 7, the battery pack effectively disperses and absorbs battery expansion force, reduces the risk of stress concentration, and has the advantages of improving overall structural stability and extending service life.

[0036] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0037] The above descriptions are merely embodiments of this utility model. Commonly known structures and characteristics are not described in detail here. Those skilled in the art are aware of all common technical knowledge in the field prior to the application date or priority date, are knowledgeable of all existing technologies in that field, and possess the ability to apply conventional experimental methods prior to that date. Therefore, those skilled in the art can, based on the guidance provided in this application, improve and implement this solution in conjunction with their own capabilities. Typical known structures or methods should not be obstacles for those skilled in the art to implement this application. It should be noted that those skilled in the art can make several modifications and improvements without departing from the structure of this utility model. These modifications and improvements should also be considered within the scope of protection of this utility model, and will not affect the effectiveness of the implementation of this utility model or the practicality of the patent. The scope of protection claimed in this application should be determined by the content of its claims, and the specific embodiments described in the specification can be used to interpret the content of the claims.

Claims

1. A battery pack end plate, characterized in that: It includes an end plate body and a connecting support plate integrally formed on the top of the end plate body. The connection position between the end plate body and the connecting support plate is formed by continuous bending to form an inclined transition section. The transition section is inclined outward so that the connecting support plate and the end plate body form a misaligned structure.

2. The battery pack end plate according to claim 1, characterized in that: The end plate body is also provided with a buffer cavity, which extends vertically upward from the bottom end of the end plate body to the transition section. Multiple buffer cavities are provided, and the multiple buffer cavities are spaced apart laterally along the end plate body.

3. The battery pack end plate according to claim 1, characterized in that: The transition section forms an angle α with the vertical direction, and the angle α is 20°-25°.

4. The battery pack end plate according to claim 2, characterized in that: The end plate body protrudes outward to form the buffer cavity, the depth of which is 1.5-2.0 mm.

5. A battery fixing assembly, comprising a battery pack end plate as described in any one of claims 1-4, characterized in that: It also includes a fixed beam frame and a liquid-cooled plate assembly. The liquid-cooled plate assembly includes a horizontally arranged liquid-cooled base plate. There are two parallel end plate bodies, which are respectively located at both ends of the liquid-cooled base plate along its length. The bottoms of the two end plate bodies are respectively detachably connected to both ends of the liquid-cooled base plate along its length. The fixed beam frame is located above the liquid-cooled base plate. The two ends of the fixed beam frame along its length are respectively detachably connected to the connecting support plates corresponding to the two end plate bodies.

6. The battery fixing assembly according to claim 5, characterized in that: The liquid-cooled plate assembly also includes multiple vertically arranged liquid-cooled baffles, which are arranged in parallel between the two end plate bodies. The bottom of the liquid-cooled baffles is connected to the liquid-cooled base plate, and the top of the liquid-cooled baffles is connected to the fixed beam frame.

7. The battery fixing assembly according to claim 5, characterized in that: Connecting plates are installed at both ends of the fixed beam frame along its length. The connecting plates are attached to the connecting support plates and are detachably connected to form a connection between the fixed beam frame and the end plate body. The connecting plates protrude outward to form multiple limiting bosses. The connecting support plates are provided with multiple limiting grooves corresponding to the multiple limiting bosses. The limiting bosses are inserted into the limiting grooves when the connecting plates and the connecting support plates are connected.

8. The battery fixing assembly according to claim 7, characterized in that: The connecting support plate has rectangular overlapping notches at both ends, and the two ends of the connecting plate protrude outward to form overlapping flanges. When the connecting plate and the connecting support plate are connected, the overlapping flanges overlap and fit against the overlapping flanges.

9. A battery pack comprising a battery fixing assembly as described in any one of claims 5-8, characterized in that: It also includes battery modules, and battery modules are provided between the end plate body and the adjacent liquid-cooled partition, as well as between any adjacent liquid-cooled partitions.

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