High-integration power battery pack and design method

Abstract

The invention relates to the technical field of lithium ion power batteries, and discloses a high-integration power battery pack and a design method.The high-integration power battery pack comprises a module integrally arranged in a box, and the bottom of the module is arranged in the box; a cross beam of an n-shaped structure is arranged in the box body, a hollow inner cavity is formed in the middle of the cross beam, a BMS module is arranged in the inner cavity of the cross beam, the BMS module is in direct insertion connection with a CCS module, and the CCS module is connected with a battery cell electrode end of the module; an integrated cold plate is arranged at the bottom of the box body, cooling pipelines are arranged on the two side faces of the box body respectively, and the cooling pipelines are connected with a pipeline assembly in an inner cavity of the cross beam. According to the invention, an end plate structure is canceled, the cross beam is adopted to replace an end plate, and parts are integrated in the cross beam, so that the volume and mass grouping efficiency is improved, the energy density is maximized in a limited space, the overall cost is reduced, and the lightweight design is realized.

Description

Technical Field

[0001] This invention relates to the field of lithium-ion power battery technology, specifically to a highly integrated power battery pack and its design method. Background Technology

[0002] In existing power battery systems, the traditional battery pack architecture adopts a separate layout, that is, the battery management system (BMS) and the module are designed independently, and rely on a complex wiring harness network to achieve signal sampling and control connection. This not only occupies more battery pack space, but also increases system weight and manufacturing cost.

[0003] Meanwhile, with the increasing demand for fast charging of power batteries, the requirements for thermal management are also increasing. Traditional bottom cooling solutions are no longer sufficient to meet the heat dissipation requirements under high-power charging conditions, and additional cooling measures need to be introduced. Although these measures can alleviate the temperature rise problem, they require more space, which means that the battery layout space needs to be further compressed, resulting in a decrease in energy density and a sacrifice of battery capacity.

[0004] In addition, current module structures generally rely on end plates for support to meet the mechanical preload requirements of the entire module. While this structure can ensure the stability of the module structure, it also increases the number of parts and assembly complexity, and increases the overall weight, thereby further restricting the power battery system's energy performance and fast charging performance. Summary of the Invention

[0005] The present invention aims to provide a highly integrated power battery pack and its design method to solve the problems of low integration, low volume / weight packing ratio, large volume and weight, low energy per unit space, low thermal management efficiency and high manufacturing cost of existing power battery packs.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: a highly integrated power battery pack, comprising a module integrally disposed within a housing, the bottom of which is disposed within the housing; a crossbeam with a U-shaped structure is provided within the housing, the middle of which has a hollow inner cavity, and a BMS module is disposed within the inner cavity of the crossbeam, the BMS module being directly connected to a CCS module, the CCS module being connected to the battery cell terminals of the module; the bottom of the housing is an integrated cold plate, and cooling pipes are respectively provided on two sides of the housing, the cooling pipes being connected to the pipe assembly in the inner cavity of the crossbeam.

[0007] Meanwhile, this solution also provides a highly integrated power battery pack design method, applied to the aforementioned power battery pack, including the following steps: Step 1: Aluminum profiles are extruded and formed into a box body, and a cooling plate is formed at the bottom of the box body; Step 2: Set the crossbeam as a hollow structure, and install the BMS module and piping assembly inside the crossbeam; splice the crossbeam into a Z-shaped structure and set it inside the box to replace the end plate; Step 3: Install cooling pipes on both sides of the housing and connect the cooling pipes to the pipe assembly; Step 4: Push out the battery cell terminals, weld the busbar between the terminals, and put the battery cell module into the box as a whole; Step 5: Install the CCS module, connect the CCS module to the bus, and directly connect the BMS module to the CCS module. The principle and advantages of this scheme are: In traditional battery pack design, the integrity and long-term reliability of the battery system require battery modules to perform multiple functions, including mechanical support, force transmission, and safety assurance. Since the battery pack itself cannot perform these functions, end plates are introduced into the structural design. End plates apply pre-tightening force to resist cell expansion, maintain structural stability, ensure tight contact between cells, and prevent localized overheating or performance degradation caused by loosening. They also support cell welding points, preventing incomplete soldering or breakage, and can be integrated with cooling structures. Furthermore, after lithium batteries are stacked, they are clamped into the housing by tooling at both ends, and since the cells cannot bear force, end plates are also necessary. In traditional structures, the crossbeam is part of the housing, integrated and welded together, and only serves to support the housing. Therefore, in existing technologies, end plates are considered an indispensable key component; eliminating end plates would compromise the stability of the battery pack.

[0008] This solution breaks away from traditional technological thinking, boldly eliminating the bulky and complex end plate. The existing crossbeam structure is optimized into a detachable structure with a hollow design for placing pipelines and components, providing greater layout space. Through clever combination of crossbeams, it can directly replace the end plate while meeting the structural performance requirements of the battery pack. Externally, it functions as an end plate, bearing the force of tooling; internally, it constrains the battery pack, acting as a support beam and constraining the battery cells, thus creatively achieving a technical solution that eliminates the need for an end plate structure.

[0009] Furthermore, by directly embedding the BMS module and piping assembly into the crossbeam, the battery pack achieves higher integration, significantly saving space required for the cooling assembly, greatly reducing the internal space occupied by the casing, decreasing the number of components and wiring structures, and providing more space for energy units. This increases battery capacity, meeting the market's demand for high-capacity batteries, and effectively reducing the overall integrated volume and manufacturing costs. Simultaneously, the use of aluminum stamping as a cooling plate at the bottom of the casing further reduces space occupation, and the space on both sides allows for the addition of cooling pipes, forming a three-sided cooling structure. This improves overall cooling performance without requiring additional cooling equipment, meeting the system's 4C and above fast charging requirements. Attached Figure Description

[0010] Figure 1 This is a schematic diagram of the structure of a highly integrated power battery pack according to the present invention.

[0011] Figure 2 This is a flowchart illustrating a highly integrated power battery pack design method according to the present invention.

[0012] The markings in the accompanying drawings include: housing 1, battery module 2, battery cell 3, crossbeam 4, first crossbeam 5, second crossbeam 6, piping assembly 7, BMS module 8, cooling piping 9, CCS module 10, and cooling plate 11. Detailed Implementation

[0013] The following detailed description illustrates the specific implementation method: Example 1 This embodiment of a highly integrated power battery pack eliminates the end plate structure. By modifying and assembling the original crossbeam, the end plate structure is directly replaced, reducing the number of components, lowering the internal space occupancy, and allowing for a larger space to accommodate energy units, thus achieving an integrated structural design. Furthermore, by integrating the BMS module and piping assembly through the crossbeam, the overall integration is improved, increasing the volume / weight packing ratio, reducing production costs, and achieving the performance requirements of overall lightweighting, high capacity, fast charging, and high integration. In this embodiment, as shown in the attached... Figure 1 As shown, the power battery pack includes a box 1 with an overall square structure. In this embodiment, the box 1 is formed by extruding aluminum profiles. A cooling plate 11 is directly integrated at the bottom of the box 1. That is, there is no additional cooling equipment at the bottom of the box 1. Instead, the cooling plate 11 is directly formed by stamping profiles to reduce the use and space required for separate cooling equipment, while achieving the original cooling effect and improving the integration of the box 1.

[0014] A battery module 2 is integrally installed inside the housing 1, and the bottom of the battery module 2 is fixed to the bottom of the housing 1 by bolts. In this embodiment, the battery module 2 is composed of multiple battery cells 3. During assembly, the terminals of the battery cells 3 are pushed out to facilitate the routing of the top CCS wiring. Busbars are welded to the terminals of the battery cells 3, and the battery cells 3 in the module are connected in series or parallel through the busbars. The battery cells can be pouch cells or prismatic cells, and their corresponding terminals are tabs or terminals. This installation of the battery module 2 provides sufficient space, which is beneficial for the arrangement of the cooling pipes 9 on both sides.

[0015] A U-shaped crossbeam 4 is installed inside the housing 1 to replace the end plate structure. This eliminates the need for the end plate structure while meeting the requirements for battery pack structural stability and preload, reducing the number of components, simplifying wiring and structural connections, further reducing overall weight, and increasing internal usable space. In this embodiment, the crossbeam 4 is a detachable structure, comprising a first crossbeam 5 and a second crossbeam 6 connected sequentially by bolts. All crossbeams 4 have a hollow inner cavity in the middle. The crossbeams 4 are made of HC340 / 590DP material, with a length of 500-1300mm, a width of 15-30mm, and a height of 20-40mm. They are wider than traditional crossbeams, providing more space for internal component integration without occupying internal space in the housing 1, improving overall integration while facilitating disassembly and installation.

[0016] In this embodiment, a piping assembly 7 is fixedly installed in the inner cavity of the first crossbeam 5. The piping assembly 7 is located in the middle of the first crossbeam 5 and runs through the inner cavity of the crossbeam, greatly saving the space required for the arrangement of the piping assembly 7 while meeting cooling requirements. A BMS module 8 is provided in the inner cavity of the crossbeam. Specifically, a BMS module 8 is fixedly installed in the inner cavity of the second crossbeam 6 by bolts. The BMS module 8 is installed in the middle of the inner cavity of the second crossbeam 6 and is fixedly connected to the crossbeam by side rivets. In contrast, traditional BMS modules need to be fixed to sheet metal brackets for positioning and separate installation. This solution directly integrates the crossbeam and the BMS module, eliminating the need for sheet metal brackets, further reducing the use of parts, ensuring the stability and safety of the BMS module, and reducing the overall installation weight and space occupied.

[0017] Cooling pipes 9 are installed on two sides of the housing 1. In this embodiment, the cooling pipes 9 are adhered to the side walls of the housing 1 with thermally conductive adhesive and are ultimately connected to the pipe assembly 7 in the inner cavity of the first crossbeam 5. After the internal structure is improved, the usable space inside the housing is increased, and the integration of components is high, resulting in a smaller footprint. Based on this, additional cooling pipes 9 are added to both sides of the housing 1, forming a three-sided cooling system with the cooling plate at the bottom. This increases cooling performance without adding additional cooling equipment and reducing the occupied area, in order to meet the requirements of fast charging. At the same time, the pipes extending outward from the housing run through the crossbeam space, further reducing the occupied space and improving the overall integration, in order to meet the fast charging requirements of the system at 4C and above.

[0018] In this embodiment, the cooling pipe 9 is a single piece of stamped cold plate. Its flow channel can be U-shaped and it is fixed to the side wall of the housing 1 by thermally conductive structural adhesive, occupying about 80% of the side wall area, so as to improve the cooling effect of the cooling pipe 9 and reduce its volume to meet the needs of fast charging.

[0019] In this embodiment, a CCS module (fast charging interface) is arranged on the top of the battery module 2, allowing the low-voltage pins of the CCS module 10 to directly plug into the BMS module 8, achieving a direct connection between the BMS module 8 and the CCS module 10, eliminating the need for adapter wiring harnesses. Simultaneously, the CCS module 10 is connected to the battery cell terminals of the module via a busbar. By protruding the battery terminals, lateral space occupation is reduced, allowing for centralized wiring at the top, facilitating the centralized layout of the busbar and CCS high-voltage wiring harness, optimizing wiring space, and also enabling faster and more efficient maintenance of the CCS module and busbar without disassembling the entire battery pack. This achieves high integration while simplifying assembly and maintenance.

[0020] In this embodiment, the traditional fixed endplate design is broken away from, boldly eliminating the endplate structure and optimizing the original crossbeam design. A hollow structure is used to highly integrate multiple components, significantly reducing the space occupied by the components. Simultaneously, a clever crossbeam splicing structure is employed, allowing the crossbeams to be detachable while maintaining the required mechanical preload and stability for the battery pack. This allows the optimized crossbeams to directly serve as endplate supports, replacing the original endplate structure. The hollow crossbeams integrate the BMS and piping assembly, saving space while ensuring component performance, improving integration, simplifying assembly structure and processes, and achieving lightweight design. Furthermore, more space is available for energy units and a cooling structure, improving cooling efficiency without requiring additional cooling equipment, increasing the overall volume / weight packing ratio, reducing manufacturing costs, and enhancing both power and cooling performance to meet the demands of high-capacity, high-speed charging.

[0021] Example 2 In this embodiment, a highly integrated power battery pack design method is also provided, which is applied to the aforementioned highly integrated power battery pack, as shown in the attached figure. Figure 2 As shown, it includes the following steps: S1 is made of aluminum profile extrusion molding into a box body, and a cooling plate is formed at the bottom of the box body.

[0022] In this embodiment, the housing 1 is made of aluminum profile and manufactured by extrusion molding. The length of housing 1 is 500-2100mm, the width is 600-1500mm, and the height is 110-250mm, thereby reducing the overall volume of the battery pack and achieving weight reduction. Simultaneously, an aluminum stamping process is used to create a cooling plate, which is placed at the bottom of the housing as a bottom cooling plate, eliminating the need for a separate cooling plate, reducing the number of additional components, and achieving a cooling effect while reducing overall weight.

[0023] S2, the crossbeam is set as a hollow structure, and the BMS module and piping assembly are installed in the crossbeam respectively; the crossbeam is spliced ​​into a Z-shaped structure and placed in the box to replace the end plate.

[0024] In this embodiment, the middle part of the crossbeam 4 is set as a hollow cavity to match the highly integrated installation of other components, and the crossbeam 4 is set as a detachable and assembleable structure. Specifically, the BMS module 8 is bolted and fixed inside the first crossbeam 5, achieving pre-assembly of the first crossbeam 5 and the BMS module 8. Then, the piping assembly 7 is bolted and fixed inside the second crossbeam 6, achieving pre-assembly of the second crossbeam 6 and the piping assembly 7, greatly saving the space required for the cooling assembly.

[0025] The pre-assembled crossbeam 4 is assembled and fixed into a Z-shaped structure using bolts, and then placed into the box together with the battery module 2, and fixed to the box body 1 using bolts. The traditional end plate is eliminated, and the two detachable crossbeams functionally replace the traditional end plate, reducing the overall weight and space occupied, and further reducing costs.

[0026] S3, cooling pipes are installed on both sides of the housing, and the cooling pipes are connected to the pipe assembly.

[0027] In this embodiment, cooling pipes 9 are provided on both sides of the housing 1 and are bonded with thermally conductive adhesive to form a three-sided cooling structure, which improves cooling performance without taking up too much space. They are then connected to the pipe assembly 7 in the second crossbeam 6 to meet the fast charging requirements of 4C and above.

[0028] S4, eject the battery cell terminals, weld the bus between the terminals, and then put the battery cell module into the box as a whole.

[0029] In this embodiment, during the assembly of the battery cells, the terminals of the battery cells are protruded and busbars are welded between the terminals, allowing the battery cells to be connected in series / parallel via the busbars. After the battery cell modules are stacked and assembled, thermally conductive structural adhesive is applied to the bottom of the housing, and the entire assembly, including the crossbeam, is placed into the housing and secured with bolts. This improves the integration of the battery cell modules with the BMS module inside the crossbeam, eliminating the need for separate design and arrangement. This saves on complex wiring harnesses and space, and also eliminates the need for additional sheet metal brackets for separate installation, greatly reducing the use of components and lowering manufacturing costs.

[0030] Additionally, after the cells are stacked, the entire assembly is pre-compressed using the crossbeam 4 to ensure the stability of the cell structure, protect the connection between the electrode and the busbar, and apply a pre-tightening force to the module through the crossbeam 4 to counteract the outward thrust of the cell expansion, maintain tight contact between the cells, and avoid local overheating or performance degradation caused by loosening.

[0031] S5, install the CCS module, connect the CCS module to the bus, and directly connect the BMS module to the CCS module.

[0032] Finally, CCS module 10 is installed on top of battery module 2, so that BMS module 8 and CCS module 10 are directly connected, reducing the wiring harness between BMS module 8 and CCS module 10, reducing the use of parts, improving integration and reducing production costs.

[0033] Traditional BMS modules are designed separately and are typically located in different areas within the battery than the CCS module. This separation necessitates flexible wiring harnesses to cross these areas and accommodate vehicle structural design. Furthermore, while the CCS integrates its high-voltage terminals (DC+ / DC-) and communication terminals (CP / PP, CAN) into a single socket, the BMS only requires communication signals. Direct insertion would force high-voltage and low-voltage circuits to share an interface, violating electrical safety standards. Therefore, a wiring harness is also needed to carry the communication signals, balancing safety and flexibility. The wiring harness also transmits battery status to the CCS in real time, enabling the charging station to dynamically adjust power and prevent overcharging or overheating. Therefore, current technology considers BMS modules and CCS modules to be incompatible for direct insertion.

[0034] However, this solution breaks the inherent connection design pattern by integrating the BMS module into the crossbeam and the CCS into the battery pack, and connecting it to the battery cell through the busbar. It adopts a board-to-board connection method to achieve a direct plug-in connection between the BMS module and the CCS module, thereby overcoming the problems of spatial distance and safety, and achieving a highly integrated connection setup.

[0035] In this embodiment, the wiring of the CCS module 10 is located on the top of the cell module, which facilitates wiring and installation, as well as the arrangement of cooling pipes on both sides. This greatly reduces the overall layout space, makes installation and operation easier, and also facilitates quick disassembly and maintenance. While improving internal space, it meets the requirements of high capacity, high integration, and fast charging, achieving a lightweight design.

[0036] The above descriptions are merely embodiments of the present invention, and common knowledge such as specific technical solutions and / or characteristics are not described in detail here. It should be noted that those skilled in the art can make various modifications and improvements without departing from the technical solutions of the present invention, and these should also be considered within the scope of protection of the present invention. These modifications and improvements will not affect the effectiveness of the implementation of the present invention 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 highly integrated power battery pack, characterized in that: The device includes a module housed entirely within a housing, with the bottom of the module located within the housing. A U-shaped crossbeam is positioned within the housing, with a hollow inner cavity in the center of the crossbeam. A BMS module is housed within the inner cavity of the crossbeam, and the BMS module is directly connected to a CCS module. The CCS module is connected to the battery terminals of the module. The bottom of the housing is an integrated cold plate, and cooling pipes are located on both sides of the housing, connecting to a pipe assembly within the inner cavity of the crossbeam.

2. The highly integrated power battery pack according to claim 1, characterized in that: The crossbeam has a length of 500-1300mm, a width of 15-30mm, and a height of 20-40mm.

3. The highly integrated power battery pack according to claim 1, characterized in that: The crossbeam includes a first crossbeam and a second crossbeam connected in sequence; the pipeline assembly is located in the inner cavity of the first crossbeam; and the BMS module is located in the inner cavity of the second crossbeam.

4. The highly integrated power battery pack according to claim 1, characterized in that: The cooling pipes are attached to the side wall of the housing by thermally conductive adhesive and connected to the pipe assembly.

5. A highly integrated power battery pack according to claim 1, characterized in that: Busbars are provided at the terminals of the battery cells to connect the battery cells in the module in series or in parallel.

6. A highly integrated power battery pack according to claim 1, characterized in that: The enclosure is made of aluminum profiles.

7. A highly integrated power battery pack design method, characterized in that, The application of a highly integrated power battery pack according to any one of claims 1-6 includes the following steps: Step 1: Aluminum profiles are extruded and formed into a box body, and a cooling plate is formed at the bottom of the box body; Step 2: Set the crossbeam as a hollow structure, and install the BMS module and piping assembly inside the crossbeam; splice the crossbeam into a Z-shaped structure and set it inside the box to replace the end plate; Step 3: Install cooling pipes on both sides of the housing and connect the cooling pipes to the pipe assembly; Step 4: Push out the battery cell terminals, weld the busbar between the terminals, and put the battery cell module into the box as a whole; Step 5: Install the CCS module, connect the CCS module to the bus, and directly connect the BMS module to the CCS module.

8. The design method for a highly integrated power battery pack according to claim 7, characterized in that: The length of the box is 500-2100mm, the width is 600-1500mm, and the height is 110-250mm.

9. The design method for a highly integrated power battery pack according to claim 7, characterized in that: Step 4 also includes pre-compressing the entire group by means of a crossbeam after the cell stacking is completed.

10. The design method for a highly integrated power battery pack according to claim 7, characterized in that: The BMS module is installed in the middle of the inner cavity of the crossbeam and is fixedly connected to the crossbeam via its side.

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