Battery pack for electric motorcycle

Abstract

The utility model discloses a battery pack for an electric motorcycle, which comprises a battery bottom shell, a battery upper cover and battery modules, each battery module comprises a battery cell and a battery cell support frame, and after the two battery modules are fixedly connected, the positive electrode and the negative electrode of the battery cell are respectively welded with a battery connecting piece to form a circuit connecting loop of the battery pack. Special supporting faces are designed at the four corners of the support, a stable and accurate positioning platform is provided for battery cells, the height of the supporting faces is controlled, it is ensured that all the battery cells are evenly supported, a lifting handle and a connector of an electric motorcycle battery pack are designed in a sinking mode, the lifting handle and the connector are embedded into a shell of the battery pack, and therefore the battery pack is convenient to use. The battery pack is compact in overall structure, light in weight and high in energy density, the battery pack is easy to manufacture and assemble, the battery modules are firmly fixed, the heat exchange effect between the battery modules and the external environment is good, and heat dissipation is excellent.

Description

TECHNICAL FIELD

[0001] The utility model relates to new energy battery assembly technical field especially relates to a battery pack for electric motorcycle. BACKGROUND

[0002] With the continuous progress of technology, the energy density of electric motorcycle battery is continuously improved, the charging time is not shortened, the battery life is prolonged, which makes the endurance and performance of electric motorcycle significantly improved. Secondly, with the expansion of battery production scale, the reduction of material cost and the improvement of production process, the cost of electric motorcycle battery gradually decreases, which makes electric motorcycle more competitive.

[0003] Chinese patent document CN217655949U discloses a "high-strength electric motorcycle battery structure with heat dissipation function". It includes: a battery module, including a battery module assembly, a set of matched U-shaped sheet metal racks are arranged at the upper and lower ends of the battery module assembly, and a plurality of L-shaped sheet metal racks are fixedly connected around the U-shaped sheet metal racks; a battery aluminum cylinder, a plurality of module fixing beams are arranged on the inner wall of the battery aluminum cylinder, one end of the battery aluminum cylinder is matched with the L-shaped sheet metal rack, and the other end is fixedly connected with a set of module pressing plates through screws; a heat dissipation module matched with the battery aluminum cylinder. The above technical scheme is difficult to balance the needs of reducing the volume, increasing the high energy density and improving the heat dissipation. SUMMARY

[0004] The utility model mainly solves the technical problem that the original technical scheme is difficult to balance the needs of reducing the volume, increasing the high energy density and improving the heat dissipation, and provides a battery pack for electric motorcycle. A special supporting surface is designed at the four corners of the bracket to provide a stable and accurate positioning platform for the battery cell. The height of the supporting surface is controlled to ensure that each battery cell is uniformly supported. The handle and connector of the electric motorcycle battery pack adopt a sinking design, embedding the handle and connector into the shell of the battery pack. The overall structure of the battery pack is compact, light in weight and high in energy density. The battery pack is easy to manufacture and assemble, the battery module is fixed firmly, the heat exchange effect between the battery module and the external environment is good, and the heat dissipation is excellent.

[0005] The above-mentioned technical problems of this utility model are mainly solved by the following technical solution: This utility model includes a battery bottom shell and a battery top cover, and also includes a battery module. The battery module includes a battery cell and a battery cell support frame. After two battery modules are fixedly connected, the positive and negative terminals of the battery cells are welded to the battery connecting pieces to form the circuit connection loop of the battery pack. After the battery cells are installed on the battery cell support frame, the two battery modules are spot welded together with the battery connecting pieces, and then the two modules are fixed together with screws and nuts. The positive and negative terminals of the battery cells are welded to the connecting pieces to form the circuit connection loop of the battery pack, forming the battery module. Then, the BMS protection board and other components are installed. The battery module is then fastened and fixed to the middle section of the battery shell with screws. After the heat-conducting pads are pasted on both sides of the battery module, the front cover and rear cover of the battery shell are fastened and fixed to the battery module and the middle section of the battery shell with screws to complete the manufacture of the electric motorcycle battery pack.

[0006] Preferably, the battery cell support frame includes a first battery cell bracket and a second battery cell bracket, with a plurality of corresponding through holes on the first and second battery cell brackets. The battery bracket has a raised design around its perimeter, ensuring sufficient assembly space for the battery cells during module assembly and preventing damage to the battery cells due to external pressure when the module is locked.

[0007] Preferably, the first and second cell supports have support surfaces at their four corners, and the support surfaces of the first and second cell supports abut against each other, forming a cell placement space inside the cell support frame.

[0008] Preferably, the first and second cell supports are respectively provided with battery connecting tabs on their outer sides. The connecting tabs are made of pure nickel, with low internal resistance and low heat generation during overcurrent. The positive and negative connecting tabs of the battery module adopt a copper busbar laser-welded nickel sheet process, which can enhance the overcurrent capacity of the positive and negative positions of the battery module and reduce heat generation. The series connecting tabs between the positive and negative terminals and between the modules use a 0.5mm thick copper busbar design to ensure overcurrent capacity while reducing heat generation.

[0009] Preferably, the diameter of the through hole is larger than the diameter of the battery cell, the battery cell is placed in the through hole, and the positive and negative terminals of the battery cell abut against the battery connecting piece, respectively.

[0010] Preferably, after the two battery modules are fixedly connected, the side of the battery module is provided with a series battery connecting piece. The locking end plates on both sides of the battery module have U-shaped grooves to reserve assembly space when assembling the module.

[0011] Preferably, a BMS protection board is fixed above the battery module, and the battery connector pins are soldered to the BMS protection board. The BMS protection board is a one-piece board that can adapt to the shape of the battery bracket, reducing the number of components such as ribbon cables in conventional ribbon cable protection boards and reducing the required installation space. The BMS protection board has pre-drilled holes and is fixed to the studs of the cell bracket with screws to prevent vibration of the protection board from causing the battery connector to break or the wire harness solder joints to fall off.

[0012] Preferably, the top of the battery cover has a recess, and a battery housing handle is located in the recess. A portion of the top of the battery housing cover is recessed to accommodate a handle and connector, reducing external volume and facilitating battery pack installation and removal. The battery housing base and battery housing cover are made of aluminum alloy. The battery box bottom shell has studs for fixing the battery module to the battery housing base. Both the battery housing base and battery housing cover have screw holes, allowing them to be fastened together with screws. The shortened spacing between the screw holes on the battery box top cover effectively improves the battery box's sealing performance. The battery housing bottom shell has screws, and end plates are used on both sides of the battery module, which are tightened with nuts to reinforce module fixation.

[0013] Preferably, the top of the battery cover is further provided with a first connector and a second connector. The battery cover is pre-processed, and the first connector is fixed with the first connector screw. At the same time, the wiring harness of the first connector passes through the reserved hole in the cover, and the second connector is fixed with the second connector screw.

[0014] Preferably, the two battery modules are provided with a first double-sided adhesive epoxy board on both sides, and a second double-sided adhesive epoxy board in the middle of the battery modules. A complete battery pack consists of two identical modules connected in series, with the total positive and total negative terminals of the modules located on both sides of the modules. The modules are separated in the middle by a second double-sided adhesive epoxy board 21, and the sides are covered by the first double-sided adhesive epoxy boards. Then, end plates are pasted onto the first double-sided adhesive epoxy boards on both sides. The screw holes of the end plates, the first double-sided adhesive epoxy boards, the second double-sided adhesive epoxy boards, and the first and second cell support frames are basically aligned. Epoxy boards are used to isolate individual battery modules and between modules and end plates, providing insulation and flame retardant treatment for the modules. The end plates conduct the heat of the battery modules to the external environment, resulting in good heat exchange between the battery modules and the external environment and excellent heat dissipation.

[0015] The beneficial effects of this utility model are as follows: By designing special support surfaces at the four corners of the bracket, a stable and precise positioning platform is provided for the battery cells. The height of the support surfaces is controlled to ensure that each battery cell is evenly supported. The handle and connector of the electric motorcycle battery pack adopt a sunken design, embedding the handle and connector into the outer shell of the battery pack, making the overall structure of the battery pack compact, lightweight and high energy density. Furthermore, the battery pack is simple to manufacture and assemble, the battery modules are firmly fixed, and the heat exchange effect between the battery modules and the external environment is good, resulting in excellent heat dissipation. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the structure of this utility model.

[0017] Figure 2 This is an exploded view of a battery pack according to this utility model.

[0018] Figure 3 This is an exploded view of a battery module according to this utility model.

[0019] Figure 4 This is an exploded view of a battery connector, battery cell, and bracket according to this utility model.

[0020] Figure 5 This is a connection diagram of a battery module according to the present invention.

[0021] In the diagram, 1 is the battery housing base, 2 is the battery housing top cover, 3 is the first connector, 4 is the battery housing handle, 5 is the second connector, 6 is the top cover screw, 7 is the first end plate, 8 is the second end plate, 9 is the series battery connecting piece, 10 is the BMS protection board, 11 is the nut, 12 is the screw, 13 is the protection board screw, 14 is the first protection board battery connecting piece, 15 is the first main battery connecting piece, 16 is the second protection board battery connecting piece, 17 is the first insulating epoxy board, 18 is the connecting piece screw, 19 is the first cell bracket, 20 is the second cell bracket, 21 is the second insulating epoxy board, 22 is the cell, 23 is the second main battery connecting piece, 24 is the first connector screw, and 25 is the second connector screw. Detailed Implementation

[0022] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this application will be further described in detail below through embodiments and in conjunction with the accompanying drawings. It should be understood that the specific embodiments described herein are only one preferred embodiment of this application and are only used to explain this application. They do not limit the scope of protection of this application. All other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0023] This invention has the following advantages compared to other technologies:

[0024] 1. Ensuring the safety and stability of battery cells is crucial during the design and assembly of battery modules. Controlling the assembly height of the cells is one of the key factors in achieving this goal. To precisely control the assembly height of the cells and prevent damage during battery module tightening, the design of the support frame is essential. The four corners of the support frame are designed with dedicated support surfaces, which provide a stable and precise positioning platform for the cells. By controlling the height of these support surfaces, it can be ensured that each cell is evenly supported, and the assembly height remains within the design limits.

[0025] 2. In the design of electric motorcycle batteries, copper-nickel composite materials are used to manufacture the nickel sheets for both the positive and negative electrodes to improve battery conductivity and overall performance. This composite material combines the excellent conductivity of copper with the corrosion resistance of nickel, enabling the nickel sheets to effectively reduce internal resistance and improve energy transfer efficiency during battery charging and discharging. Simultaneously, the use of copper-nickel composite materials also enhances the mechanical strength and stability of the nickel sheets, ensuring their reliability and durability over long-term use. This design not only improves the overall performance of the battery but also provides electric motorcycles with longer driving range and enhanced safety.

[0026] 3. In electronic equipment and electrical systems, wire harness connections are crucial for ensuring stable circuit operation. Traditional wire harness connections typically employ soldering, where solder is melted by heating to form a strong electrical connection with the metal wires and connection points. However, while soldering provides reliable connections in many cases, it may not be the optimal choice for certain applications. Especially in equipment requiring frequent disassembly and maintenance, or operating in harsh environments such as vibration and impact, soldered connections can affect the stability and reliability of the equipment due to solder fatigue, cracking, or detachment. To overcome these potential problems, bolted connections are an effective alternative for wire harness connections.

[0027] 4. In battery management systems, the design and manufacture of the protection board are crucial for ensuring safe battery operation. To improve the stability and reliability of the protection board, especially in harsh working environments such as vibration and shock, its structure and connection methods require special design. Nickel sheets, as an important component of the battery pack, are responsible for battery charge and discharge management. To ensure a stable and reliable connection between the nickel sheets and the protection board, spot welding is typically used. Spot welding is a welding method that utilizes the heat generated by current passing through the contact point to locally melt the metal surface and rapidly cool and solidify, thus forming a weld joint. This method can create a strong electrical connection while keeping the connection point small, helping to reduce the impact of vibration on the connection point.

[0028] 5. Ensuring the stability and safety of battery components is crucial when designing and manufacturing battery packs. To achieve this, the connection between the protection board and the cell support needs careful design to ensure the protection board remains stable and does not shift or wobble under various operating conditions, including severe vibration and impact. In this design, fixing the protection board to the cell support with screws is a common and effective connection method. Screw fixing provides a reliable mechanical connection, ensuring good contact and fixation between the protection board and the cell support.

[0029] 6. Optimizing space utilization and increasing energy density are two important design goals when designing electric motorcycle battery packs. This utility model achieves a compact overall battery pack structure through a series of innovative designs, while ensuring functionality and safety. The handle and connectors of the electric motorcycle battery pack adopt a recessed design, embedding them into the outer shell of the battery pack instead of protruding them. The advantage of this design is that it saves space, reduces the protruding parts on the outside of the battery pack, thereby reducing the overall external dimensions and making the battery pack more compact.

[0030] Before discussing the exemplary embodiments in more detail, it should be mentioned that some exemplary embodiments are described as processes or methods depicted as flowcharts. Although the flowcharts describe the operations (or steps) as sequential processes, many of the operations (or steps) can be performed in parallel, concurrently, or simultaneously. Furthermore, the order of the operations can be rearranged. The process can be terminated when its operation is completed, but it may also have additional steps not included in the figures; the process may correspond to a method, function, procedure, subroutine, subroutine, etc.

[0031] The technical solution of this utility model will be further described in detail below through embodiments and in conjunction with the accompanying drawings.

[0032] Example: A battery pack for an electric motorcycle according to this example, such as... Figure 1 As shown, the battery pack includes a bottom shell 1 and a top cover 2, as well as a battery module. The battery module includes a cell 22 and a cell support frame. After the two battery modules are fixedly connected, the positive and negative terminals of the cell 22 are welded to battery connecting pieces to form the battery pack's circuit connection loop. After the cells are installed onto the cell support frame, the two battery modules are spot-welded together using battery connecting pieces. Then, the two modules are fixed together using screws and nuts. The positive and negative terminals of the cells are welded to the connecting pieces to form the battery pack's circuit connection loop, thus forming the battery module. Then, the BMS protection board and other components are installed. Finally, the battery module is screwed and fixed to the middle section of the battery casing. After attaching thermal pads to both sides of the battery module, the front and rear covers of the battery casing are screwed and fixed to the battery module and the middle section of the battery casing, completing the electric motorcycle battery pack manufacturing.

[0033] The battery cell support frame includes a first battery cell bracket 19 and a second battery cell bracket 20, each with a plurality of corresponding through holes. The diameter of the through holes is larger than the diameter of the battery cell 22. The battery cell 22 is placed in the through holes, with its positive and negative terminals abutting against the battery connectors, respectively. The battery bracket has a raised design around its perimeter. During module assembly, the support surfaces around the bracket ensure sufficient assembly space for the battery cells, preventing damage to the cells due to external pressure when the module is locked.

[0034] The first cell support 19 and the second cell support 20 have supporting surfaces at their four corners, which abut against each other. The inner side of the cell support frame forms the space for placing the cell 22. Battery connecting pieces are respectively provided on the outer sides of the first cell support 19 and the second cell support 20. The connecting pieces are made of pure nickel, with low internal resistance and low heat generation during overcurrent. The positive and negative connecting pieces of the battery module adopt a copper busbar laser welding nickel sheet process, which can enhance the overcurrent capacity of the positive and negative positions of the battery module and reduce heat generation. The series battery connecting pieces between the positive and negative positions of the module and between the modules use a 0.5mm thick copper busbar design to ensure overcurrent capacity while reducing heat generation.

[0035] After the two battery modules are fixedly connected, a series battery connecting piece 9 is provided on the side of the battery module. The locking end plates on both sides of the battery module have U-shaped grooves to provide assembly space during module assembly. A BMS protection board 10 is fixed on top of the battery module, and the pins of the battery connecting piece are soldered to the BMS protection board 10. The BMS protection board is a one-piece board that can adapt to the shape of the battery bracket, reducing the number of components such as ribbon cables in conventional ribbon cable protection boards and reducing the required installation space. The BMS protection board has pre-drilled holes for fixing to the studs of the cell bracket with screws to prevent vibration of the protection board from causing the battery connecting piece to break or the wire harness solder joints to detach.

[0036] The top of the battery cover 2 has a recess, where a battery housing handle 4 is located. A portion of the top of the battery housing cover is recessed to accommodate a handle and connectors, reducing external volume and facilitating battery pack installation and removal. The battery housing base and battery housing cover are made of aluminum alloy. The battery box bottom shell has studs for fixing the battery module to the battery housing base. Both the battery housing base and battery housing cover have screw holes, allowing for screw fastening. The shortened spacing between the screw holes on the battery box cover effectively improves the battery box's sealing performance. The battery housing bottom shell has screws, and end plates are used on both sides of the battery module, secured with nuts for enhanced module fixation. The top of the battery cover 2 also has a first connector 3 and a second connector 5. The battery housing cover is pre-processed, and the first connector screws are used to fix the first connector. Simultaneously, the wiring harness of the first connector passes through pre-drilled holes in the cover, and the second connector screws are used to fix the second connector.

[0037] Two battery modules are equipped with first double-sided adhesive epoxy boards 17 on both sides, and a second double-sided adhesive epoxy board 21 in the middle of the battery modules. A complete battery pack consists of two identical modules connected in series, with the total positive and total negative terminals of the modules located on both sides of the modules. The modules are separated in the middle by the second double-sided adhesive epoxy board 21, and the sides are covered by the first double-sided adhesive epoxy boards. Then, end plates are pasted onto the first double-sided adhesive epoxy boards on both sides. The screw holes of the end plates, the first double-sided adhesive epoxy boards, the second double-sided adhesive epoxy boards, and the first and second cell support frames are basically aligned. Individual battery modules and the modules and end plates are separated by epoxy boards, which provide insulation and flame retardant treatment for the modules. The end plates conduct the heat of the battery modules to the external environment, resulting in good heat exchange between the battery modules and the external environment and excellent heat dissipation.

[0038] Example 2

[0039] like Figure 4 As shown, cell 22 is installed onto cell bracket 19 and cell bracket 20. After the cell is installed, the positive and negative terminals of cell 22 are welded to battery connecting pieces 14, 15, 16, and 23 to form a continuous circuit loop for the battery pack. Connecting piece 15 is made of pure nickel, which has low internal resistance and generates less heat during overcurrent. The positive and negative connecting pieces 15 and 23 of the battery module are made using a copper busbar laser welding process to enhance the overcurrent capacity of the positive and negative positions of the battery module and reduce heat generation.

[0040] like Figure 3 As shown, a complete battery pack consists of two identical modules connected in series. The positive and negative leads of the modules are located on both sides of the module. The modules are separated in the middle by a double-sided adhesive epoxy board 21, and the two sides are covered by double-sided adhesive epoxy boards 17. Then, the end plate 7 is pasted onto the double-sided adhesive epoxy boards 17 on both sides. The screw holes of the end plate 7, the double-sided adhesive epoxy board 17, the double-sided adhesive epoxy board 21, and the screw holes of the cell support brackets 19 and 20 are basically aligned. Then, the two modules are locked together using screws 12 and nuts 11. The cell brackets 19 and 20 have pre-drilled holes on both sides, and embedded nuts are installed in the brackets. After the two modules are locked, the battery connecting piece 9 is connected in series by screws 18. At the same time, the battery connecting piece 15 is fixed on the other side by screws 18, which stretches the positive and negative leads of the battery module to the top of the battery module. Finally, install the BMS protection board 10 and fix it to the top of the module with screws 13. Then, solder the pins of each connecting piece 14 and connecting piece 16 to the BMS protection board 10. This completes the assembly of the battery module. The battery connecting pieces 15 at the positive and negative positions of the battery and the battery connecting pieces connected in series between the module use copper busbars.

[0041] like Figure 2As shown, the battery casing cover is pre-processed, and the connector 3 is fixed with screw 24. At the same time, the wiring harness of the connector 3 passes through the reserved hole in the cover, and the connector 5 is fixed with screw 25.

[0042] like Figure 2 , Figure 5 As shown, the battery module completed according to the above assembly steps is assembled with the screw of the outer casing base through the U-shaped hole reserved on the end plate. The battery module is fixed together with the battery casing base using nut 11. The connector wire harness of the battery casing cover 2 is soldered to the protection plate. After the battery casing cover 2 and the battery casing base 1 are combined, the cover is locked with screw 6.

[0043] The specific embodiments described herein are merely illustrative examples illustrating the spirit of the invention. The above embodiments only express several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of this patent application. It should be noted that those skilled in the art to which this application pertains can make various modifications or additions to the described specific embodiments or use similar methods to substitute them, but without departing from the spirit of this application or exceeding the scope defined by the appended claims. For those skilled in the art, multiple variations and improvements can be made without departing from the concept of this application. Therefore, the scope of protection of this patent should be determined by the appended claims.

Claims

1. A battery pack for an electric motorcycle, comprising a battery bottom shell (1) and a battery top cover (2), characterized in that, It also includes a battery module, which includes a cell (22) and a cell support frame. After the two battery modules are fixedly connected, the positive electrode of the cell (22) and the negative electrode of the cell (22) are respectively welded to the battery connecting piece to form the circuit connection loop of the battery pack. The battery cell support frame includes a first battery cell bracket (19) and a second battery cell bracket (20) with support surfaces at the four corners, and the support surfaces of the two abut against each other to form a space for placing the battery cell (22).

2. A battery pack for an electric motorcycle according to claim 1, characterized in that, The first cell support (19) and the second cell support (20) are provided with a plurality of corresponding through holes.

3. A battery pack for an electric motorcycle according to claim 1 or 2, characterized in that, The first cell bracket (19) and the second cell bracket (20) are respectively provided with battery connecting pieces on their outer sides.

4. A battery pack for an electric motorcycle according to claim 2, characterized in that, The diameter of the through hole is larger than the diameter of the battery cell (22). The battery cell (22) is placed in the through hole, and the positive and negative terminals of the battery cell (22) abut against the battery connecting piece, respectively.

5. A battery pack for an electric motorcycle according to claim 1, characterized in that, After the two battery modules are fixedly connected, a series battery connecting piece (9) is provided on the side of the battery module.

6. A battery pack for an electric motorcycle according to claim 3, characterized in that, A BMS protection board (10) is fixed above the battery module, and the battery connector pins are soldered to the BMS protection board (10).

7. A battery pack for an electric motorcycle according to claim 1, characterized in that, The top of the battery cover (2) has a recess, and the recess has a battery casing handle (4).

8. A battery pack for an electric motorcycle according to claim 1 or 7, characterized in that, The top of the battery cover (2) is also provided with a first connector (3) and a second connector (5).

9. A battery pack for an electric motorcycle according to claim 3, characterized in that, The two battery modules are provided with a first double-sided adhesive epoxy board (17) on both sides, and a second double-sided adhesive epoxy board (21) is provided in the middle of the battery module.

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