A sodium and lithium electric bicycle battery pack

Abstract

The application discloses a sodium battery and lithium battery electric bicycle battery pack and belongs to the technical field of energy storage.The electric bicycle battery pack comprises an aluminum barrel, a module is arranged in the aluminum barrel, the module is provided with a pole lug at the bottom, and the inner bottom of the aluminum barrel is provided with a heat-conducting silica gel pad in contact with the pole lug.The scheme solves the problems of high safety risk, low heat dissipation efficiency, insufficient light weight, weak structural strength, good disassembling property, low development cost, long cyclic service life and good scene adaptability.

Description

Technical Field

[0001] This invention relates to the field of energy storage technology, specifically to a sodium-electric and lithium-electric electric bicycle battery pack. Background Technology

[0002] With the rapid iteration of new energy technologies, sodium-ion batteries and lithium-ion batteries are increasingly widely used in the field of electric bicycle power supply due to their respective electrochemical advantages. As a core power component, the comprehensive performance of the electric bicycle battery pack directly determines the vehicle's range, safety, and market competitiveness. Currently, the performance requirements for electric bicycle batteries are becoming increasingly stringent. On the one hand, they have high requirements for safety characteristics such as thermal runaway prevention, heat dissipation, resistance to mechanical damage, and sealing. On the other hand, they require lightweight, low-cost, and simple structure. Furthermore, battery packs also face the risk of cell explosion due to thermal runaway, and the narrow internal space of the battery pack leads to low heat dissipation efficiency, exacerbating safety hazards and causing capacity decay due to excessive temperature differences between cells. Moreover, balancing lightweight and structural strength is difficult; the wall thickness of mainstream aluminum casings on the market often exceeds 3mm, resulting in an excessively high weight ratio and failing to meet lightweight requirements. While plastic casings are lighter, they have shortcomings in mechanical performance such as vibration resistance, impact resistance, and drop resistance. Therefore, existing technologies have proposed new battery pack technologies, such as the existing patented technology W... Application O2025108091A1 discloses a battery pack in which the heat-conducting component includes a flexible heat-conducting element that is thermally connected to the battery cell module. This allows for rapid heat transfer from the battery cell module to the flexible heat-conducting element. Furthermore, the flexible heat-conducting element is elastically deformable, ensuring good contact with the heat dissipation part of the lower housing. This guarantees a tight contact between the flexible heat-conducting element and the heat dissipation part, reliably transferring heat to the flexible heat-conducting element and ultimately rapidly dissipating it outside the lower housing. Another example is existing patent WO2025251230A1, which discloses an energy storage device. This technology uses a first fan to drive a first refrigerant to flow between a first gap, a second gap, and a refrigerant channel to dissipate heat from the battery module. Through a heat exchanger, the first refrigerant exchanges heat with the heat exchanger, further improving heat dissipation efficiency. While these existing technologies have addressed some shortcomings of battery packs, such as heat dissipation, there is still room for improvement in areas such as fire and explosion resistance, structural strength, and weight reduction. Summary of the Invention

[0003] The purpose of this invention is to provide a sodium-ion and lithium-ion battery pack for electric bicycles, which solves the problems of high safety risk, low heat dissipation efficiency, insufficient lightweight and weak structural strength of the battery pack. It also has good disassembly and low development cost, long cycle life and good adaptability to various scenarios.

[0004] To address the aforementioned technical problems, this invention specifically provides the following technical solution: a sodium-ion and lithium-ion electric bicycle battery pack, comprising an aluminum barrel, a module built into the aluminum barrel, a tab at the bottom of the module, and a thermally conductive silicone pad in contact with the tab at the bottom of the aluminum barrel. This invention, by setting a thermally conductive silicone pad at the bottom of the aluminum barrel, enables the tab at the bottom of the module to form a flexible, gapless fit with the aluminum barrel. Utilizing the metal shell of the aluminum barrel as a heat dissipation base, it achieves rapid heat conduction and temperature equalization of the tab, reducing the temperature difference of the battery cells, thus improving the heat dissipation efficiency and cycle life of the battery pack.

[0005] According to one embodiment of the present invention, the module includes battery cells stacked sequentially at intervals, with high-resilience foam filling the spaces between the battery cells. An adapter plate is provided above the stacked battery cells, and a first foam is provided at the bottom. The first foam is a plate-shaped MPP foam that covers the bottom space of the stacked battery cells. The high-resilience foam is also plate-shaped, with a width less than or equal to the width of the battery cells and a height less than the height of the battery cells. By filling the spaces between the stacked battery cells with plate-shaped high-resilience foam, laying the first MPP foam at the bottom of the battery cells, and simultaneously providing an adapter plate above the battery cells, an overall module structure is formed. The high-resilience foam fills the gaps between the battery cells to prevent shaking and can accommodate slight deformation of the battery cells. Furthermore, as the battery cells expand in the later stages of their lifespan, the battery cells compress the high-resilience foam, releasing space. The first foam provides cushioning protection for the bottom of the battery cells. The adapter plate and the foam work together to form a stable whole, improving the structural strength and vibration resistance of the module, while buffering the structural stress caused by the deformation of the battery cells during operation, thus extending the service life of the battery cells and the module.

[0006] According to one embodiment of the present invention, a first foam support block is filled between the cells below the adapter plate; the first foam support block is a strip structure used to fill the gap at the top of the cell. In the subsequent flip assembly process, after potting, this area, i.e. the top of the cell, is mainly supported by the first foam support block and potting compound. This can replace the top seal of the cell as the main load-bearing carrier in the flip state of the module, effectively avoiding the risk of damage to the top seal of the cell due to concentrated force, and at the same time strengthening the connection stability between the cell and the adapter plate.

[0007] According to one embodiment of the present invention, the module is placed in a module support with a placement space. The inner wall of the module support and the sides of the stacked battery cells have first expansion foam. The first expansion foam is a large plate-like structure used to fill the gap between the module support and the stacked battery cells of the module. An opening is left at the top of the module support for tearing the sealed bag attached to the first expansion foam. By providing the first expansion foam on the inner wall of the module support and the sides of the stacked battery cells, the gap between the battery cells and the support is filled, preventing the module from shaking or shifting within the support, improving the overall vibration and impact resistance of the module. At the same time, the first expansion foam can expand and compress the battery cells, providing a continuous and stable preload force to the battery cells.

[0008] According to one embodiment of the present invention, there are fire extinguishing beads arranged in an array between the thermally conductive silicone pad and the module; by arranging the fire extinguishing beads in an array between the thermally conductive silicone pad and the module, the fire extinguishing beads can respond quickly and release fire extinguishing agent when thermal runaway occurs, so as to achieve rapid fire extinguishing at the source of the fire.

[0009] According to one embodiment of the present invention, there are at least two thermally conductive silicone pads with a fire extinguishing bead between them. The double-layer thermally conductive silicone pads improve the damage resistance and heat conduction efficiency of the thermally conductive structure, ensuring stable heat exchange between the electrode tab and the aluminum barrel. At the same time, the fire extinguishing bead is fixed in the heat source area by the thermally conductive silicone pads, and can quickly sense and release the fire extinguishing agent in the event of thermal runaway.

[0010] According to one embodiment of the present invention, the edge of the thermally conductive silicone pad in contact with the module is filled with a first foam support block. The strip-shaped structure of the first foam support block achieves seamless edge filling, ensuring that the heat from the tab is efficiently transferred to the aluminum tank via the thermally conductive silicone pad. In addition, the first foam support block provides edge support for the thermally conductive silicone pad while preventing it from curling or falling off due to vibration and impact.

[0011] According to one embodiment of the present invention, the module is placed in an inverted position inside an aluminum drum. After the module is placed in the drum, the aluminum drum is placed upright and then potting adhesive is injected for sealing. This achieves a potting layer of more than 30mm at the bottom. The installation method of the module and aluminum drum in the present invention differs from the traditional upright placement method. After the module is placed in the aluminum drum, the sealing bag of the first expansion foam is torn open, allowing the first expansion foam to expand and connect with the external atmosphere, compressing the battery cell to achieve pre-tightening force loading.

[0012] Based on a method for assembling sodium-ion and lithium-ion battery packs for electric bicycles, the assembly method involves: stacking battery cells sequentially at intervals, filling the spaces between the cells with high-resilience foam, laying a first layer of foam at the bottom of the stacked cells, and welding an adapter plate to the top to achieve electrical connection between the cells, forming a cell assembly; placing the cell assembly into a module bracket, and then inverting the module bracket containing the cell assembly into an aluminum drum. This invention uses the high-resilience foam and the first layer of foam to form a positioning and buffering structure for the cells in the initial assembly stage, preventing the cells from shaking during assembly and subsequent use. The overall inverted mounting of the module bracket ensures that the module and the heat-conducting structure inside the aluminum drum are aligned and fitted, eliminating assembly gaps and ensuring efficient heat dissipation.

[0013] An electric bicycle battery pack with preload loading includes an aluminum drum. A module is placed inverted within the aluminum drum. Each module comprises battery cells stacked sequentially at intervals. The module is placed within a module support with a placement space. The inner wall of the module support and the sides of the stacked battery cells are provided with first expansion foam. By inverting the module into the aluminum drum and simultaneously providing the first expansion foam on the inner wall of the module support and the sides of the stacked battery cells, the expansion properties of the foam are utilized to create a continuous and uniform compressive force on the battery cells, stably loading a preload load onto the cells. This improves the cycle life of the battery cells. Furthermore, the inverted module design, combined with the support and foam wrapping structure, reduces cell movement and displacement.

[0014] According to one embodiment of the present invention, high-resilience foam is filled between the battery cells, an adapter plate is provided above the stacked battery cells, and a first foam is provided at the bottom. The high-resilience foam fills the gaps between the battery cells and adapts to their working deformation to prevent shaking and displacement, while the first foam provides bottom cushioning protection for the battery cells.

[0015] A cover for an electric bicycle battery pack includes a top cover with a handle, a pressure relief hole with a diameter greater than 8mm, an annular wire mesh bonded to the pressure relief hole, and a first ventilated membrane above the annular wire mesh. The pressure relief hole is used to quickly release internal high-temperature and high-pressure gas to avoid the risk of explosion. The annular wire mesh provides physical protection for the first ventilated membrane to prevent it from being punctured by sharp objects and losing its sealing and ventilating function. At the same time, the handle and the pressure relief protection structure are integrated into the top cover, realizing an integrated design of the cover's functions.

[0016] According to one embodiment of the present invention, the protective plate built into the top cover provides physical protection for the protective plate by embedding it inside the top cover, thereby avoiding the risk of damage caused by collisions and bumps, and at the same time achieving an integrated layout of the protective plate and other electrical components inside the top cover.

[0017] According to one embodiment of the present invention, a socket is installed on the top cover. The socket is wired close to electrical components such as the protective plate built into the top cover, reducing exposed wiring and improving the electrical protection level of the battery pack.

[0018] According to one embodiment of the present invention, the top cover can be assembled with an aluminum bucket. The top cover is located inside the end of the aluminum bucket, and the gap between the top cover and the aluminum bucket forms a potting groove. A potting layer is formed in the potting groove by potting adhesive. The top cover and the aluminum bucket are fixedly connected by fixing bolts. The top cover is located inside the end of the aluminum bucket, and the gap between the two forms a potting groove and a potting layer is formed by potting adhesive. The potting layer achieves a seamless seal of the assembly gap, thereby improving the overall sealing performance of the battery pack. At the same time, it does not require thickening the aluminum bucket wall to achieve a seal, which is suitable for the lightweight design of thin aluminum buckets. The gap structure of the potting groove also makes the sealing layer detachable, which is beneficial to reducing the difficulty of subsequent maintenance and disassembly compared with traditional structural adhesive sealant. Attached Figure Description

[0019] To more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are merely exemplary, and those skilled in the art can derive other embodiments based on the provided drawings without creative effort.

[0020] Figure 1 This is a schematic diagram of a sodium-electric and lithium-electric bicycle battery pack according to the present invention; Figure 2 This is a schematic diagram showing the disassembled structure of a sodium-electric and lithium-electric bicycle battery pack according to the present invention; Figure 3 This is a schematic diagram showing the positional relationship between the adapter plate, the fire extinguishing beads, the thermally conductive silicone pad, and the aluminum bucket of the present invention. Figure 4 This is a schematic diagram of the disassembled upper cover of the present invention; Figure 5 This is a schematic diagram of the stacked battery cells and adapter board of the present invention. Figure 6 This is a schematic diagram showing the stacked battery cells, the first foam support block, and the connection between the first foam and the present invention. Figure 7 This is a schematic diagram showing the connection between the stacked battery cells and the first expansion foam of the present invention; Figure 8 This is a schematic diagram of the installation of the module and module bracket of the present invention; Figure 9 This is a schematic diagram showing the first foam support block and the thermally conductive silicone pad installed in the assembled state of the module and module bracket of the present invention. Figure 10 This is a schematic diagram showing the assembly relationship between the thermally conductive silicone pad and the fire extinguishing bead of the present invention; Figure 11 This is a schematic diagram showing the installation of the module and the aluminum bucket after the fire extinguishing beads and thermal conductive silicone pads are installed according to the present invention. Figure 12 This is a first-view schematic diagram of the upper cover of the present invention; Figure 13 This is a schematic diagram of the upper cover of the present invention from a second perspective; Figure 14 This is a schematic diagram illustrating the installation of the top cover, aluminum bucket, and module of the present invention; Figure 15 A schematic diagram showing the placement of an adhesive layer between the top cover and the aluminum drum; Figure 16 This is a schematic diagram of the internal structure of a sodium-electric and lithium-electric bicycle battery pack. Figure 17 for Figure 16 Enlarged view of region A in the image; Figure 18 A schematic diagram showing the installation of a protective cover on the upper part of the cover.

[0021] Explanation of reference numerals in the attached drawings: 10. Aluminum bucket; 11. Fixing bolt; 12. Fire extinguishing bead; 13. Thermally conductive silicone pad; 14. Filler adhesive; 20. Top cover; 21. Handle; 22. Potting layer; 23. Protective cover; 24. Socket; 25. Protective plate; 26. Pressure relief hole of top cover; 27. Annular wire mesh; 28. First breathable membrane; 29. ​​Label; 30. Module bracket; 40. Module; 41. First expansion foam; 42. First foam support block; 43. Adapter plate; 44. High resilience foam; 45. First foam; 46. Battery cell. Detailed Implementation

[0022] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0023] The concepts involved in this application will first be described with reference to the accompanying drawings. It should be noted that the following descriptions of various concepts are only for the purpose of making the content of this application easier to understand and do not constitute a limitation on the scope of protection of this application; furthermore, the embodiments and features in the embodiments of this application can be combined with each other unless otherwise specified. This application will now be described in detail with reference to the accompanying drawings and embodiments.

[0024] Example 1: As shown in the attached figure Figures 1-4 As shown, a sodium-ion and lithium-ion battery pack for electric bicycles includes an aluminum barrel 10, with a module 40 built into the aluminum barrel 10. The bottom of the module 40 has tabs, and the bottom of the aluminum barrel 10 has a thermally conductive silicone pad 13 that contacts the tabs. This invention, by setting the thermally conductive silicone pad 13 at the bottom of the aluminum barrel 10, creates a flexible, gapless fit between the tabs at the bottom of the module 40 and the aluminum barrel 10. Utilizing the metal shell of the aluminum barrel 10 as a heat dissipation base, it achieves rapid heat conduction and temperature equalization of the tabs, reducing the temperature difference of the battery cells, thus improving the heat dissipation efficiency and cycle life of the battery pack.

[0025] As shown in the attached figure Figures 5-7As shown, the module 40 includes battery cells 46 stacked sequentially at intervals, with high-resilience foam 44 filling the spaces between the battery cells 46. An adapter plate 43 is located above the stacked battery cells 46, and a first foam 45 is located at the bottom. The first foam 45 is a plate-shaped MPP foam that can cover the bottom space of the stacked battery cells 46. The high-resilience foam 44 is also plate-shaped, with its width less than or equal to the width of the battery cells 46 and its height less than the height of the battery cells 46. By filling the spaces between stacked battery cells 46 with plate-shaped high-resilience foam 44, laying MPP material first foam 45 at the bottom of battery cells 46, and setting an adapter plate 43 above battery cells 46 to form an overall module 40 structure, the high-resilience foam 44 fills the gaps between battery cells to prevent shaking and can accommodate the slight deformation of battery cells 46. In the later stages of the battery cell 46's life, it will expand. At this time, the battery cell 46 will squeeze the high-resilience foam 44, and the foam will release space. The first foam 45 will provide cushioning protection for the bottom of the battery cell 46. The adapter plate 43 and the foam work together to make the module 40 a stable whole, improve the structural strength and vibration resistance of the module 40, and buffer the structural stress caused by the working deformation of the battery cell 46, thus extending the service life of the battery cell 46 and the module 40.

[0026] The space between the battery cells 46 below the adapter plate 43 is filled with a first foam support block 42. The first foam support block 42 is a strip structure used to fill the gap at the top of the battery cell 46. In the subsequent flip assembly process, after potting, this area, that is, the top of the battery cell 46, is mainly supported by the first foam support block 42 and potting compound. This can replace the top seal of the battery cell 46 as the main load-bearing carrier in the flip state of the module 40, effectively avoiding the risk of damage to the top seal of the battery cell 46 due to concentrated force, and at the same time strengthening the connection stability between the battery cell 46 and the adapter plate 43.

[0027] As shown in the attached figure Figure 8 As shown, the module 40 is placed within a module support 30 with a placement space. The inner wall of the module support 30 and the sides of the stacked battery cells 46 have first expansion foam 41. The first expansion foam 41 is a large, plate-like structure used to fill the gap between the module support 30 and the stacked battery cells 46 of the module 40. An opening is provided at the top of the module support 30 for tearing the sealed bag attached to the first expansion foam 41. By placing the first expansion foam 41 on the inner wall of the module support 30 and the sides of the stacked battery cells 46, the gap between the battery cells 46 and the support 30 is filled, preventing the module 40 from shaking or shifting within the support 30, thus improving the overall vibration and impact resistance of the module 40. Simultaneously, the first expansion foam 41 can expand and compress the battery cells 46, providing a continuous and stable preload force to the battery cells 46.

[0028] As shown in the attached figure Figures 2-3As shown, there are fire extinguishing beads 12 arranged in an array between the thermally conductive silicone pad 13 and the module 40; by arranging the fire extinguishing beads 12 in an array between the thermally conductive silicone pad 13 and the module 40, the fire extinguishing beads 12 can respond quickly and release fire extinguishing agent when thermal runaway occurs, so as to achieve rapid fire extinguishing at the source of the fire.

[0029] As shown in the attached figure Figure 10 As shown, there are at least two thermally conductive silicone pads 13, with fire extinguishing beads 12 between them. The double-layer thermally conductive silicone pads 13 improve the damage resistance and heat conduction efficiency of the thermally conductive structure, ensuring stable heat exchange between the electrode tab and the aluminum barrel 10. At the same time, the fire extinguishing beads 12 are fixed in the heat source area by the thermally conductive silicone pads 13, and can quickly sense and release the fire extinguishing agent in the event of thermal runaway.

[0030] As shown in the attached figure Figure 9 As shown, the edge of the thermally conductive silicone pad 13 that contacts the module 40 is filled with a first foam support block 42. The strip structure of the first foam support block 42 achieves seamless edge filling, ensuring that the heat from the tab is efficiently transferred to the aluminum barrel 10 via the thermally conductive silicone pad 13. In addition, the first foam support block 42 provides edge support for the thermally conductive silicone pad 13 while preventing it from curling or falling off due to vibration and impact.

[0031] As shown in the attached figure Figure 11 As shown, module 40 is placed inverted into aluminum drum 10. After module 40 is placed in the drum, aluminum drum 10 is placed upright and then potting adhesive is injected for sealing. This achieves a potting layer of more than 30mm at the bottom. The installation method of module 40 and aluminum drum 10 in this invention differs from the traditional upright method. After module 40 is placed into aluminum drum 10, the sealed bag of the first expansion foam 41 is torn open, allowing the first expansion foam 41 to expand and connect with the external atmosphere, compressing the battery cell to achieve pre-tightening force loading.

[0032] Example 2: See appendix Figure 1 -Appendix Figure 11 As shown, an electric bicycle battery pack with preload includes an aluminum drum 10. A module 40 is placed inverted inside the aluminum drum 10. The module 40 includes battery cells 46 stacked sequentially at intervals. The module 40 is placed inside a module support 30 with a placement space. The inner wall of the module support 30 and the sides of the stacked battery cells 46 have first expansion foam 41. By inverting the module 40 into the aluminum drum 10 and simultaneously providing the first expansion foam 41 on the inner wall of the module support 30 and the sides of the stacked battery cells 46, the expansion characteristics of the foam are used to form a continuous and uniform compressive force on the battery cells 46, thus stably loading a preload onto the battery cells 46. This improves the cycle life of the battery cells 46. In addition, the inverted module 40 combined with the wrapping structure of the support 30 and the foam 41 also reduces the shaking and displacement of the battery cells 46.

[0033] High-resilience foam 44 is filled between the battery cells 46. An adapter plate 43 is provided above the stacked battery cells 46, and a first foam 45 is provided at the bottom. The high-resilience foam 44 fills the gaps between the battery cells and adapts to their working deformation to prevent shaking and displacement. The first foam 45 provides bottom cushioning protection for the battery cells 46.

[0034] Example 3: A method for manufacturing a sodium-electric and lithium-ion battery pack for electric bicycles is as follows: This invention uses module 40 inverted; the specific placement method is shown in the appendix. Figure 2 -Appendix Figure 3 As shown. Two layers of soft, thermally conductive silicone pads 13 are placed between the battery cell tabs and the aluminum canister 10. Combined with the pressure generated by the battery's own weight, heat is transferred from the tabs to the thermally conductive silicone pads, and then to the aluminum canister. Utilizing the short transmission distance of this transmission channel, along with the battery's own pressure and the softness of the thermally conductive silicone pads, seamless heat transfer is achieved, improving heat dissipation efficiency. Further details are shown in the appendix. Figure 5 Appendix Figure 6 As shown, first foam support blocks 42 are added to both sides of the electrode tab and the top sealing gap of the battery cell 46 to avoid overpressure at the electrode tab. It should be noted that the height of the first foam support block 42 needs to be slightly lower than that of the thermal conductive silicone pad 13. Then, the module 40 is inverted and then filled with glue. When the thermal conductive silicone pad 13 is deformed by overpressure, the cured glue layer on both sides and the first foam support block 42 support the entire module 40 to prevent the thermal conductive silicone pad 13 from being damaged by overpressure.

[0035] See appendix Figure 3 -Appendix Figure 11 As shown, the flexible battery cells are fixed together after being sprayed with adhesive, as... Figure 5 As shown, based on the internal dimensions of the battery pack, a high-resilience foam 44 can be added every few cells 46 to provide pre-tightening force and expansion space. Next, the module 40 is welded with an adapter plate 43 to achieve electrical connection between the cells 46. See appendix. Figure 6 As shown, a first foam 45 is added to the bottom of the battery cell 46 for protection, and a first foam support block 42 is inserted to fill the top seal of the battery cell 46. In the subsequent flip-chip assembly process, after potting, this area, i.e., the top seal of the battery cell 46, is mainly supported by the first foam support block 42 and the potting compound, rather than the thin battery cell top seal itself supporting the weight of the entire module 40, thereby improving the structural strength of the module 40. Next, see the appendix... Figure 7 Appendix Figure 8 As shown, after attaching the first expansion foam 41 to the large side of the stacked battery cells 46, the bare module is inserted into the module bracket 30. The top of the module bracket 30 has an opening for tearing open the sealed bag attached to the first expansion foam 41. Then, see attached... Figure 9 As shown, a first layer of thermally conductive silicone pad 13 is attached to the battery pack tabs, and a first foam support block 42 is attached to the side to fill the gaps on both sides. See attached diagram. Figure 10As shown, a layer of fire extinguishing beads 12 is added above the first layer of thermally conductive silicone pad 13, and then another thin thermally conductive silicone pad 13 is added to fix the fire extinguishing beads 12. The added fire extinguishing beads 12 are used to release fire extinguishing agent when heated in the event of thermal runaway of the battery, thereby extinguishing open flames. Then, see the appendix. Figure 11 As shown, the thin aluminum bucket 10 is inverted to install the module 40. After the module 40 is inserted into the bucket, the aluminum bucket 10 is placed upright and then potting adhesive is injected to achieve a potting layer of more than 30mm at the bottom. After the module 40 is inserted into the aluminum bucket 10, the sealed bag of the first expansion foam 41 is torn open, allowing the first expansion foam 41 to expand and connect with the external atmosphere, compressing the battery cell to achieve pre-tightening force loading. The inverted battery cell is used to improve safety. If thermal runaway occurs, the flame will be directly facing the bottom of the aluminum bucket 10, which is welded at the bottom, thus preventing the flame from spreading. In addition, there is a fire extinguishing bead 12 on the front of the battery cell, which releases fire extinguishing agent to extinguish the fire when the battery cell is heated due to thermal runaway. This invention achieves heat dissipation while ensuring the uniform temperature requirements inside the battery through the tabs, thermally conductive silicone pads 13, aluminum bucket 10, and battery self-weight pressurization structure, reducing the problem of battery pack capacity reduction caused by large temperature differences between battery cells due to positional deviation.

[0036] Example 4: A cover for an electric bicycle battery pack, see attached. Figure 1 -Appendix Figure 4 and appendix Figure 12 -Appendix Figure 18 As shown, The top cover 20 is pre-installed with a protective plate 25, a socket 24, and a handle 21. The handle 21 is bolted to ensure quick switching between different applications. Under the mandatory requirement of the new national standard for all-metal casings, a low-cost fabric handle can be used for initial assembly in the ToC market, while a steel-coated handle is used in the ToB market to meet frequent lifting needs, making the battery pack compatible with both market demands. The top cover 20 has a pressure relief hole 26, where a ring-shaped steel wire mesh 27 is first bonded before the first vent membrane 28 is attached. The diameter of the pressure relief hole 26 is greater than 8mm for rapid pressure relief, especially in extreme cases where a large amount of high-temperature and high-pressure gas is inside the battery, preventing extreme situations such as "explosion". The ring-shaped steel wire mesh 27 serves as a daily protective cover for the pressure relief hole 26, preventing sharp objects from puncturing the first vent membrane 28 and causing air leakage. The pre-installed top cover 20 is then installed onto the aluminum bucket 10 and secured with the first bolts 11 around the perimeter. A potting groove is formed between the top cover 20 and the aluminum cylinder 10. A sealing ring or filler adhesive 14 can be used to cover the assembly gap between the top cover 20 and the aluminum cylinder 10. Then, adhesive is poured into the potting groove to form a potting layer 22. The potting groove is at least 5mm wide, facilitating subsequent battery disassembly by scraping the adhesive layer with a flathead screwdriver. After potting, a ring-shaped protective cover 23 is installed on top. The bottom of the protective cover 23 protrudes and adheres to the potting layer 22, or it can be fixed using side bolts. This protective cover 23 serves as a physical protective cover for the potting layer 22, preventing it from being punctured by sharp objects and also blocking sunlight, thus avoiding accelerated aging of the adhesive layer after exposure to light. This invention, using an aluminum cylinder 10 and a magnesium alloy top cover 20, can effectively protect the battery cells while meeting the requirements for a lightweight battery pack, resulting in a lighter weight and higher strength than commonly used plastic casing solutions. More importantly, the component structure of the thin aluminum cylinder and magnesium alloy top cover effectively shortens the mold opening cycle. The mold-making cycle for commonly used aluminum buckets is within 3 weeks. Compared to all-magnesium alloy shells, magnesium alloy top covers have smaller dimensions and shorter mold-making cycles. Furthermore, the mold-making cost for aluminum buckets is significantly lower than that for magnesium alloy die-cast parts. Smaller magnesium alloy top cover structures are also easier and cheaper to mold than larger all-magnesium alloy structures, resulting in cost savings in product mold-making. This makes them particularly suitable for use in the field of electric bicycle battery packs.

[0037] In this embodiment, the TOC market refers to the TOC battery pack market sold to the general public, while the TOB market refers to the TOB battery pack market sold to users in the sharing market, such as food delivery services.

[0038] It should be noted that the aluminum bucket 10 used in this invention has a thickness of 1.7mm, which, compared to the conventional thickness of 3mm or more, achieves both weight reduction and cost reduction. A grooved structure is added to the outer surface of the aluminum bucket to improve the strength of the battery pack.

[0039] It should also be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on this application. Unless otherwise expressly specified and limited, the terms "installed," "connected," "linked," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication between two elements. For those skilled in the art, the specific meaning of the above terms in this application can be understood according to the specific circumstances.

[0040] The embodiments and / or implementation methods described above are merely preferred embodiments and / or implementation methods for implementing the technology of the present invention, and are not intended to limit the implementation methods of the technology of the present invention in any way. Any person skilled in the art can make some modifications or alterations to other equivalent embodiments without departing from the scope of the technical means disclosed in the content of the present invention, but they should still be regarded as the technology or embodiments that are substantially the same as the present invention.

[0041] This document uses specific examples to illustrate the principles and implementation methods of this application. The descriptions of the above embodiments are only for the purpose of helping to understand the methods and core ideas of this application. The above descriptions are only preferred embodiments of this application. It should be noted that due to the limitations of written expression, while there are objectively infinite specific structures, those skilled in the art can make several improvements, modifications, or changes without departing from the principles of this application, and can also combine the above technical features in an appropriate manner. These improvements, modifications, changes, or combinations, or the direct application of the inventive concept and technical solution to other situations without modification, should all be considered within the scope of protection of this application.

Claims

1. A sodium-electric and lithium-electric electric bicycle battery pack, comprising an aluminum barrel (10), wherein the aluminum barrel (10) contains a built-in module (40), characterized in that, The module (40) has tabs at the bottom, and the aluminum barrel (10) has a thermally conductive silicone pad (13) at the bottom that contacts the tabs.

2. The sodium-ion and lithium-ion battery pack for electric bicycles according to claim 1, characterized in that, The module (40) includes battery cells (46) stacked sequentially at intervals, with high-resilience foam (44) filling the spaces between the battery cells (46), an adapter plate (43) above the stacked battery cells (46), and a first foam (45) at the bottom.

3. A sodium-ion and lithium-ion battery pack for electric bicycles according to claim 2, characterized in that, The first foam support block (42) is filled between the cells (46) below the adapter plate (43).

4. A sodium-ion and lithium-ion battery pack for electric bicycles according to claim 3, characterized in that, The module (40) is placed in a module support (30) with a placement space, and the inner wall of the module support (30) and the side of the stacked cells (46) have a first expansion foam (41).

5. A sodium-ion and lithium-ion battery pack for electric bicycles according to claim 1, characterized in that, Preferably, there are at least two thermally conductive silicone pads (13), and fire extinguishing beads (12) are placed between the thermally conductive silicone pads (13). Preferably, the edge of the thermally conductive silicone pad (13) that contacts the module (40) is filled with a first foam support block (42).

6. A sodium-ion and lithium-ion battery pack for electric bicycles according to claim 1, characterized in that, The module (40) is placed in the aluminum barrel (10) upside down. After the module (40) is placed in the barrel, the aluminum barrel (10) is placed upright and then potting glue is injected for potting.

7. A method for packaging and assembling sodium-ion and lithium-ion batteries for electric bicycles according to any one of claims 2-6, characterized in that, The assembly method is as follows: The battery cells (46) are stacked in sequence at intervals, and high-resilience foam (44) is filled between the battery cells (46). The first foam (45) is laid at the bottom of the stacked battery cells (46), and the top is welded with an adapter plate (43) to realize the electrical connection between the battery cells and form a battery cell assembly. Place the above-mentioned battery cell assembly into the module bracket (30), and invert the module bracket (30) containing the battery cell assembly into the aluminum bucket (10).

8. An electric bicycle battery pack with preload, characterized in that, Includes an aluminum bucket (10), the module (40) is placed in the aluminum bucket (10) in an upside-down manner, the module (40) includes battery cells (46) stacked at intervals in sequence, the module (40) is placed in a module support (30) with a placement space, and the inner wall of the module support (30) and the side of the stacked battery cells (46) have a first expansion foam (41).

9. An electric bicycle battery pack with preload as described in claim 8, characterized in that, The cells (46) are filled with high-resilience foam (44), and a converter plate (43) is provided above the stacked cells (46) and a first foam (45) is provided at the bottom.

10. A cover for an electric bicycle battery pack, comprising a top cover (20) having a handle (21), characterized in that, The upper cover (20) has an upper cover pressure relief hole (26), and an annular wire mesh (27) is bonded to the upper cover pressure relief hole (26). A first breathable membrane (28) is provided above the annular wire mesh (27). Preferably, the upper cover (20) has a built-in protective plate (25); Preferably, the upper cover (20) is equipped with a socket (24); Preferably, the top cover (20) can be assembled with the aluminum barrel (10) in the sodium-electric and lithium-electric bicycle battery pack according to claim 1. The top cover (20) is located on the inner side of the end of the aluminum barrel (10). The gap between the top cover (20) and the aluminum barrel (10) forms a potting groove, and a potting layer (22) is formed in the potting groove by potting glue.

Images