Soft package battery cell combined module

Abstract

The utility model embodiment relates to a kind of soft package battery cell combination module, including multiple intermediate protective rubber frame, two end plate rubber frame, multiple soft package battery cell, at least one heat conduction plate and positive and negative pole series lamination aluminum row;Through intermediate battery cell protective rubber frame and two side end plate rubber frame, the protection and free flexible assembly of soft package battery cell are realized, by the use of parallel (copper) aluminum composite row and series lamination aluminum row, soft package battery cell can be freely and flexibly increased in capacity by parallel connection, and series connection is increased to the required voltage range value in the structural protection of soft package battery cell, the free flexible grouping of soft package battery cell is realized, using heat-conducting composite material plate can control the overall module in the charging and discharging process, so that temperature is always controlled within the best temperature that battery cell material can use.

Description

Technical Field

[0001] This utility model relates to the field of pouch batteries, and more particularly to a pouch battery cell assembly module. Background Technology

[0002] Compared to prismatic and cylindrical batteries, pouch cells offer advantages such as lighter weight, higher energy density, and lower internal resistance, making them a mainstream technology in solid-state battery development. However, pouch cells face numerous challenges in their assembly design, including structural fragility and difficulty in integrating heating and heat dissipation. While mature temperature control module solutions exist for prismatic and cylindrical batteries, pouch cells lag behind in this area. With the increasing application of batteries in high-rate charging and discharging scenarios, the requirements for temperature control are becoming increasingly stringent, thus necessitating a highly efficient thermal management module structure suitable for pouch cells. Utility Model Content

[0003] The purpose of this utility model is to address the shortcomings of existing technologies by providing a soft-pack battery cell assembly module. This module utilizes a central battery cell protective frame and end plate frames on both sides to protect the soft-pack battery cells and allow for flexible assembly. The use of parallel (copper) aluminum composite busbars and series laminated aluminum busbars allows for flexible parallel connection to increase cell capacity and series connection to increase the required voltage range. In terms of structural protection of the soft-pack battery cells, this module achieves flexible assembly. The use of thermally conductive composite material plates ensures that the overall module temperature remains within the optimal operating temperature range for the battery cell materials during charging and discharging.

[0004] To achieve the above objectives, this utility model provides a soft-pack battery cell assembly module, comprising: multiple intermediate protective frames, two end plate frames, multiple soft-pack battery cells, at least one heat-conducting plate, and positive and negative electrode series-connected stacked aluminum busbars; wherein,

[0005] The intermediate protective frame is a hollow structure, and the soft-pack battery cell is inside. Multiple intermediate protective frames are interconnected.

[0006] The end plate frame is provided with the soft-pack battery cell inside, and the two end plate frames are respectively set on the outside of the middle protective frame at both ends.

[0007] The tabs of the soft-pack battery cell are connected by parallel copper-aluminum composite busbars and parallel aluminum composite busbars;

[0008] The heat-conducting plate includes a heat-conducting main plate and two cover plates disposed on both sides of the heat-conducting main plate; the heat-conducting main plate is disposed between two connected soft-pack cells, and the cover plates are disposed outside the middle protective rubber frame to cover the outside of multiple middle protective rubber frames.

[0009] The positive and negative electrode series-connected stacked aluminum busbars connect the intermediate protective frame and the end plate frame in series.

[0010] Preferably, the heat-conducting plate is provided with positioning holes, and the side of the intermediate protective frame is provided with guide pins that cooperate with the positioning holes, thereby fixing the heat-conducting plate within the intermediate protective frame.

[0011] Preferably, the top, sides, and bottom of the intermediate protective frame and the end plate frame are provided with buckles and slots, thereby achieving interlocking between two adjacent frames.

[0012] Preferably, the thickness of the intermediate protective frame is 0.2mm-0.4mm greater than the thickness of the solid-state battery cell.

[0013] Preferably, the positive and negative electrode series-connected stacked aluminum busbars and the adhesive frame are welded together using a laser welding machine.

[0014] Preferably, the parallel copper-aluminum composite busbar and the parallel aluminum composite busbar are welded to the tabs of the solid-state battery cell using a laser welding machine; the top of the intermediate protective frame and the end plate frame are both provided with screw holes, and the frames are reinforced and connected through the screw holes and bolts.

[0015] Preferably, the pouch cell is a pouch solid-state cell.

[0016] Preferably, the end plate frame is provided with horizontal and vertical reinforcing ribs on the outer side.

[0017] Preferably, the positive and negative electrode series-connected stacked aluminum busbars carry a current of 600-1200A.

[0018] Preferably, the motherboard and the cover plate are integrated and connected.

[0019] This utility model provides a soft-pack battery cell assembly module. The module utilizes a central battery cell protective frame and two end plate frames to protect the soft-pack battery cells and allow for flexible assembly. By using parallel (copper)-aluminum composite busbars and series-connected stacked aluminum busbars, the module can be flexibly connected in parallel to increase cell capacity, and connected in series to increase the required voltage range. This structural protection of the soft-pack battery cells enables flexible assembly. The use of thermally conductive composite material plates ensures that the overall module temperature remains within the optimal range for the battery cell materials during charging and discharging. Attached Figure Description

[0020] Figure 1 A schematic diagram of a soft-pack battery cell assembly module provided in this embodiment of the present invention;

[0021] Figure 2 An exploded view of a soft-pack battery cell assembly module provided in an embodiment of this utility model;

[0022] Figure 3 A schematic diagram of an intermediate protective frame structure provided for an embodiment of this utility model;

[0023] Figure 4 A schematic diagram of an end plate frame structure provided for an embodiment of this utility model;

[0024] Figure 5 A schematic diagram of a heat-conducting plate structure provided for an embodiment of this utility model;

[0025] Figure 6 A schematic diagram of a positive and negative electrode series-connected stacked aluminum busbar structure provided for an embodiment of this utility model;

[0026] Figure 7 A comparison chart of test results for two sets of modules provided for an embodiment of this utility model.

[0027] In the diagram: 1. Middle protective frame; 2. End plate frame; 21. Reinforcing rib; 3. Soft-pack battery cell; 31. Parallel copper-aluminum composite busbar; 32. Parallel aluminum composite busbar; 4. Heat-conducting plate; 41. Heat-conducting main plate; 42. Cover plate; 5. Positive and negative electrode series laminated aluminum busbar; 6. Buckle; 7. Screw hole; 8. Module label. Detailed Implementation

[0028] The technical solution of this utility model will be further described in detail below with reference to the accompanying drawings and embodiments.

[0029] Figure 1 This is a schematic diagram of a soft-pack battery cell assembly module provided in an embodiment of the present invention. Figure 2 An exploded view of a soft-pack battery cell assembly module provided in this embodiment of the present invention, combined with... Figure 1 and Figure 2 As shown in the figure, the soft-pack battery cell assembly module provided by this utility model includes multiple intermediate protective frames 1, two end plate frames 2, multiple soft-pack battery cells 3, at least one heat-conducting plate 4, and positive and negative electrode series stacked aluminum busbars 5. Its structure will be described in detail below.

[0030] Middle protective frame 1, combined Figure 3As shown, the intermediate protective frame 1 is used to protect the intermediate soft-pack battery cell 3. The intermediate protective frame 1 has a hollow structure, with the soft-pack battery cell 3 inside. The soft-pack battery cell 3 is secured inside the intermediate protective frame 1. Multiple intermediate protective frames 1 are interconnected. In a specific example, the top, sides, and bottom of the intermediate protective frame 1 are provided with buckles 6 and matching slots, thereby achieving interlocking between adjacent frames. After assembly, the frame is firmly and reliably assembled. The buckles 6 have a dimensional tolerance of 0.2mm, which satisfies the need for tight clamping while allowing for a small amount of movement. Preferably, for ease of installation, the top and bottom of the intermediate protective frame 1 are clearly distinguishable, making it easy to identify by both manual labor and equipment. Furthermore, rotating the intermediate protective frame 1 180° around its central axis reveals that both sides are identical, eliminating any directional requirements during installation. Additionally, there are easy-to-align guide protrusions at the four corners, facilitating alignment during installation. Optionally, the size of the protective frame is equal to or slightly larger than the thickness of the battery cell. In this embodiment, the thickness of the middle protective frame 1 is 0.2mm-0.4mm larger than the thickness of the solid battery cell. For example, the thickness of the frame can be 10mm. For a 10mm thick battery cell, there is an expansion space of 0.2-0.4mm. The thickness of the frame can be adjusted in the thickness direction according to the thickness of the battery cell, and the adjustable space is between 8-16mm.

[0031] End plate frame 2, combined Figure 4 As shown, the end plate frame 2 is used to protect the soft-pack battery cells 3 at both ends. It is a bottom plate plus frame structure, and the soft-pack battery cells 3 are installed inside the end plate frame 2. The soft-pack battery cells 3 are snapped into the end plate frame 2. The two end plate frames 2 are respectively set on the outside of the middle protective frame 1 at both ends. It can be understood that the top, sides and bottom of the end plate frame 2 are also provided with buckles 6 and matching slots, thereby realizing the interlocking between the end plate frame 2 and the middle protective frame 1. Preferably, the end plate frame 2 is provided with horizontal and vertical reinforcing ribs 21 on the outside to reinforce the structure of the end plate frame 2 and enhance the overall rigidity of the material. The above-mentioned middle protective frame 1 and end plate frame 2 solve the problem that soft-pack batteries are more fragile and easily damaged than square hard-shell batteries and cylindrical batteries. The middle protective frame 1 can be freely assembled, which is more flexible, and a foolproof design is implemented.

[0032] In some preferred embodiments, to achieve a stable connection between the frames, screw holes 7 are provided on the top of both the intermediate protective frame 1 and the end plate frame 2. The frames are reinforced by bolts through the screw holes 7, with a preload of approximately 8-12 N / mm. 2 In addition, a module label 8 can be affixed to one of the endplate frames 2 to display module information.

[0033] Optionally, the materials used for the aforementioned intermediate protective frame 1 and end plate frame 2 are primarily ABS with flame-retardant coatings. These materials possess high strength and toughness, and their flame-retardant properties meet the UL94-V0 standard, effectively preventing fire risks caused by internal short circuits in the lithium battery. Currently, the normal operating temperature of the battery is -10℃ to 55℃, with an optimal operating temperature of 25℃±5℃. The material's high-temperature resistance is approximately 80℃-90℃, and its short-term temperature resistance can reach 100℃. ABS material only gradually undergoes a glass transition when the temperature exceeds 105℃.

[0034] The soft-pack battery cell 3, preferably a soft-pack solid-state battery cell, has a positive electrode tab and a negative electrode tab, which are connected by a parallel aluminum composite busbar 32 and a parallel copper-aluminum composite busbar 31, respectively. Preferably, the parallel copper-aluminum composite busbar 31 and the parallel aluminum composite busbar 32 are welded to the electrode tab of the solid-state battery cell by a laser welding machine. The parallel copper-aluminum composite busbar 31 and the parallel aluminum composite busbar 32 allow the modules to be freely and flexibly connected in parallel to increase the battery cell capacity.

[0035] Specifically, the positive electrode parallel aluminum composite busbar 32 uses 1060 pure aluminum conductive blocks, which are made of the same material as the battery cell tabs. Its size is larger than that of the battery cell tabs to meet the discharge current requirements. The negative electrode parallel copper-aluminum composite busbar 31 uses copper-aluminum composite busbars because laser connection is required. A special high temperature and high pressure method or diffusion welding method is used to make the pure aluminum conductive blocks inside have copper material with a thickness of about 0.2mm at the required positions.

[0036] The copper-aluminum composite busbar has an outer layer of copper (resistivity 0.017 μΩ·m) and an inner layer of aluminum (resistivity 0.029 μΩ·m). Current preferentially flows through the outer copper layer, so the overall resistivity is close to that of copper, but slightly higher (approximately 0.025 μΩ·m). The pure aluminum busbar has a resistivity of 0.029 μΩ·m, but its conductivity is only 63% that of copper, resulting in higher internal resistance for the same cross-sectional area. In this example, the composite busbar is 80 mm long and 3 mm thick, capable of carrying a current of approximately 600-1200 A, which is essentially an oversized design. The welding area is slightly smaller than the tab width of 70*2 mm. It should be noted that those skilled in the art can select and set the above dimensions according to their needs.

[0037] Heat conduction plate 4, combined with Figure 5As shown, a thermally conductive composite material plate is used for heating or dissipating heat from the battery cell. The module of this application can be connected to a liquid cooling system to achieve heat dissipation. That is, the thermally conductive composite material plate provides heat conduction between the module and the liquid cooling system, thereby dissipating heat from the inside of the battery cell, and correspondingly, heating can be achieved. The thermally conductive plate 4 is disposed between two adjacent soft-pack battery cells 3. The thermally conductive plate 4 specifically includes a thermally conductive main plate 41 and two cover plates 42 disposed on both sides of the thermally conductive main plate 41. The main plate and the cover plates 42 can be integrated. Among them, the thermally conductive main plate 41 is disposed between two connected soft-pack battery cells 3, and the cover plates 42 are disposed on the outside of the intermediate protective frame 1, which can cover the outside of multiple intermediate protective frames 1. It should be noted that the number of heat-conducting plates 4 can be one or more. Those skilled in the art can select and set the number of heat-conducting plates 4 as needed. Specifically, the number can be flexibly added according to different operating conditions and the power of different liquid cooling units, ensuring the battery module operates permanently at a suitable temperature. Specifically, when using liquid cooling units of the same power, solid-state pouch battery modules have different application areas. In low-speed, mining machinery, and tunnel traction fields, the battery capacity is larger, and the discharge current rate of the battery module is smaller, allowing for a reduction in the amount of heat-conducting composite material plates used, thus reducing costs. In passenger vehicles and commercial applications, there is a demand for fast charging and instantaneous high-rate discharge of batteries, resulting in faster heat generation. Therefore, the amount of heat-conducting composite material plates can be increased, allowing the heat from the battery module to be rapidly transferred through the heat-conducting composite material plates and exchanged with the liquid cooling system, ensuring the battery module operates at a suitable temperature.

[0038] In some preferred embodiments, in order to fix the heat-conducting plate 4 and the intermediate protective frame 1, a positioning hole is provided on the heat-conducting plate 4, that is, a positioning hole is provided on the cover plate 42 of the heat-conducting plate 4, and a guide pin that cooperates with the positioning hole is provided on the side of the intermediate protective frame 1, thereby fixing the heat-conducting plate 4 in the intermediate protective frame 1.

[0039] Optionally, the thermally conductive composite material plate mainly uses 6-series aluminum, with a thermal conductivity of approximately 201-209 W / (m·K). It is mixed with other metals, such as copper powder (380–401 W / (m·K), diamond powder (1900–2200 W / (m·K), and graphite (1500–1800 W / (m·K),) to improve the overall thermal conductivity of the material plate to approximately 350-400 W / (m·K), which is close to that of copper plates, but the price is about 28% of that of copper. While approaching the thermal conductivity of copper plates, the cost is greatly reduced.

[0040] Positive and negative electrode series stacked aluminum busbar 5, combined Figure 6As shown, the intermediate protective frame 1 and the end plate frame 2 are connected in series. Preferably, the positive and negative electrode series-connected aluminum busbar 5 and the frame are welded together using a laser welding machine. The positive and negative electrode series-connected aluminum busbar 5 allows the module to be freely and flexibly connected in series to increase to the required voltage range. Preferably, the bottom of the positive and negative electrode series-connected aluminum busbar 5 can be provided with multiple slots. Correspondingly, a connecting boss can be snapped between the tops of two adjacent intermediate protective frames 1. The bottom is provided with through holes for fixing the parallel copper-aluminum composite busbar 31 and the parallel aluminum composite busbar 32. The boss is inserted into the slots and welded to achieve the fixation between the intermediate protective frame 1, the soft-pack battery cell 3, the parallel copper-aluminum composite busbar 31, the parallel aluminum composite busbar 32, and the positive and negative electrode series-connected aluminum busbar 5. In this example, the positive and negative electrode series-connected aluminum busbars can be made of 1-series or 6-series pure aluminum material with a thickness of 0.1mm. They can then be stacked according to different current requirements. After hot pressing and punching at the required locations for parallel or series battery connections, the parallel connector bosses and the aluminum busbars are fitted together and then laser-welded. Further, in a specific example, its length can be 83mm and its thickness 3mm, capable of carrying a current of approximately 600-1200A, which is essentially an overload design.

[0041] The above is a detailed description of a soft-pack battery cell assembly module structure provided by this utility model embodiment. The intermediate protective frame and end plate frames of the module are both made of insulating material, providing insulation and protection for the fragile soft-pack battery cells. Parallel (copper) aluminum composite busbars and series laminated aluminum busbars connect the battery cells in parallel and in series. The thermally conductive composite material plate provides heat conduction between the module and the liquid cooling system. Based on this structural understanding, the specific assembly steps of the module are described below.

[0042] (1) Place the processed soft-pack battery cells and parallel copper-aluminum composite and parallel aluminum composite busbars together in the welding fixture of the auxiliary group. The required number of parallels can be formed according to the design requirements. Then place them in the laser welding area and use a laser welding machine to laser weld the battery cell tabs and parallel copper-aluminum composite busbars and parallel aluminum composite busbars to make them firmly connected and meet the requirements of tensile strength and overcurrent.

[0043] (2) Assemble the welded module and the middle protective frame together. The outermost part is protected by the end plate frame. The plastic protective shell is made of easy-to-remove buckles for convenient operation.

[0044] During this process, be sure to insert the required number of thermally conductive composite material plates. Both the protective frame and the thermally conductive composite material plates have corresponding mating holes for easy operation, but pay attention to the consistency of the direction during installation.

[0045] (3) After assembly, the module is then placed in series and parallel stacked aluminum plates and laser welded.

[0046] Furthermore, in order to verify the thermally conductive composite material plate, this application also provides temperature response curves of modules with and without thermally conductive composite material plates under the same test conditions.

[0047] The test environment was 25±3℃. The test process was as follows: 1) The battery module was fully charged at 0.5C; 2) It was left to stand for 5 minutes; 3) The battery module was fully discharged at 0.5C; 4) It was left to stand for 5 minutes; 5) The battery module was fully charged at 0.5C; 6) It was left to stand for 5 minutes; 7) The battery module was fully discharged at 0.5C. It is understandable that in different applications, the module's temperature sensor can take different shapes, such as teardrop or patch type, and be evenly distributed at the location where it is attached to the battery cell or below the connecting aluminum busbar through the gaps in the central protective frame. The feedback method is to collect temperature data through battery management systems such as BMS and BCU, and to comprehensively manage the temperature, charging / discharging current, voltage, and other factors.

[0048] Using a liquid-cooled unit, modules with and without thermally conductive composite material plates were tested under the same environmental and test conditions for two charge-discharge cycles. Figure 7 As shown, the temperature difference is approximately 10-15℃, indicating that the module containing thermally conductive composite material plates can effectively improve the battery's lifespan and safety.

[0049] This utility model provides a soft-pack battery cell assembly module. The module utilizes a central battery cell protective frame and two end plate frames to protect the soft-pack battery cells and allow for flexible assembly. By using parallel (copper)-aluminum composite busbars and series-connected stacked aluminum busbars, the module can be flexibly connected in parallel to increase cell capacity, and connected in series to increase the required voltage range. This structural protection of the soft-pack battery cells enables flexible assembly. The use of thermally conductive composite material plates ensures that the overall module temperature remains within the optimal range for the battery cell materials during charging and discharging.

[0050] In this utility model, the term "multiple" refers to two or more unless otherwise explicitly defined. The terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; "linking" can be a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0051] In the description of this utility model, it should be understood that the terms "upper", "lower", "left", "right", "front", "rear", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or unit referred to must have a specific orientation or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0052] In the description herein, the terms "a specific embodiment," "some embodiments," "one embodiment," etc., refer to a specific feature, structure, material, or characteristic described in connection with that embodiment or example, which is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0053] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of this utility model. It should be understood that the above description is only a specific embodiment of this utility model and is not intended to limit the scope of protection of this utility model. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this utility model should be included within the scope of protection of this utility model.

Claims

1. A soft-pack battery cell assembly module, characterized in that, The soft-pack battery cell assembly module includes multiple intermediate protective frames, two end plate frames, multiple soft-pack battery cells, at least one heat-conducting plate, and positive and negative electrode series-connected stacked aluminum busbars; wherein... The intermediate protective frame is a hollow structure, and the soft-pack battery cell is inside. Multiple intermediate protective frames are interconnected. The end plate frame is provided with the soft-pack battery cell inside, and the two end plate frames are respectively set on the outside of the middle protective frame at both ends. The tabs of the soft-pack battery cell are connected by parallel copper-aluminum composite busbars and parallel aluminum composite busbars; The heat-conducting plate includes a heat-conducting main plate and two cover plates disposed on both sides of the heat-conducting main plate; the heat-conducting main plate is disposed between two connected soft-pack cells, and the cover plates are disposed outside the middle protective rubber frame to cover the outside of multiple middle protective rubber frames. The positive and negative electrode series-connected stacked aluminum busbars connect the intermediate protective frame and the end plate frame in series.

2. The soft-pack battery cell assembly module according to claim 1, characterized in that, The heat-conducting plate is provided with positioning holes, and the side of the middle protective frame is provided with guide pins that cooperate with the positioning holes, thereby fixing the heat-conducting plate within the middle protective frame.

3. The soft-pack battery cell assembly module according to claim 1, characterized in that, The top, sides, and bottom of the intermediate protective frame and the end plate frame are provided with buckles and slots, thereby achieving interlocking between two adjacent frames.

4. The soft-pack battery cell assembly module according to claim 1, characterized in that, The thickness of the intermediate protective frame is 0.2mm-0.4mm greater than the thickness of the solid-state battery cell.

5. The soft-pack battery cell assembly module according to claim 1, characterized in that, The positive and negative electrode series-connected stacked aluminum busbars and the plastic frame are welded together by a laser welding machine; the parallel copper-aluminum composite busbars and parallel aluminum composite busbars are welded to the tabs of the soft-pack battery cell by a laser welding machine.

6. The soft-pack battery cell assembly module according to claim 1, characterized in that, The pouch cell is a pouch solid-state cell.

7. The soft-pack battery cell assembly module according to claim 1, characterized in that, Both the top of the intermediate protective frame and the end plate frame are provided with screw holes, and the frames are reinforced and connected through the screw holes and bolts.

8. The soft-pack battery cell assembly module according to claim 1, characterized in that, The end plate frame is provided with horizontal and vertical reinforcing ribs on the outside.

9. The soft-pack battery cell assembly module according to claim 1, characterized in that, The positive and negative electrode series-connected stacked aluminum busbars can carry a current of 600-1200A.

10. The soft-pack battery cell assembly module according to claim 1, characterized in that, The motherboard and cover plate are integrated and connected.

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