Battery pack with balanced bus, and scooter battery module with the battery pack

Abstract

The present invention belongs to the field of battery technology and provides a battery cell assembly with balanced current distribution and a scooter battery module equipped with the battery cell assembly. The battery cell assembly with balanced current distribution includes: four brackets, two groups of 21700 battery cells, and two groups of nickel sheets. The 21700 battery cells are secured by screw columns on the four brackets. The two groups of nickel sheets adopt a symmetrical balanced current distribution design, and the difference in overcurrent path resistance of each 21700 battery cell is ≤5%. The present invention adopts a symmetrical balanced current distribution design, which effectively improves the uniformity of current distribution between the battery cell groups and avoids battery cell overheating and damage caused by uneven current distribution. The four brackets firmly secure the two groups of 21700 battery cells via the screw column structure, ensuring the stability and safety of the battery cell assembly during scooter operation.

Description

Technical Field

[0001] The present invention relates to the technical field of batteries, and in particular to a battery cell group with balanced current collection and a scooter battery module with the battery cell group. Background Art

[0002] Traditional scooter battery modules utilize an asymmetric busbar design, resulting in significant differences in the current paths of the positive and negative nickel plates. This design places excessive loads on some cells (especially those near the protection board, where current density is higher), leading to abnormally high local temperatures, shortened service life, and insufficient overall battery life stability. Furthermore, the layout of multiple series-parallel battery packs (such as the 13S5P) is too loose, and the cells are not compactly arranged, resulting in space utilization rates over 30% lower than the industry average. The staggered cells require flying leads for jumper connections, and the insulation of solder joints relies on heat shrink tubing or glue, which can easily cause short circuits or even fires due to insulation failure. The male mold bracket relies primarily on glue or double-sided tape for fastening, which cannot pass a 1.5-meter drop test, and the plastic casing is also insufficiently waterproof.

[0003] Therefore, it is necessary to provide a battery cell group with balanced current and a scooter battery module with the battery cell group. Summary of the Invention

[0004] The present invention provides a battery cell group with balanced current collection and a scooter battery module with the battery cell group. Through the balanced current collection design, uniform current distribution between battery cells is achieved, effectively avoiding the problem of battery cell overload in traditional asymmetric current collection design, significantly reducing local temperature rise abnormalities, extending the service life of the battery cells, and improving the stability of overall endurance. The battery cell group adopts a compact arrangement, which greatly improves space utilization. Compared with the traditional multi-series and parallel battery pack layout, the space utilization is increased by more than 30%. In addition, a flying wire-free design is adopted between the battery cells, and all connections are processed by reliable welding and insulation, avoiding the risk of short circuit and fire caused by insulation failure. A stable bracket is used to fix the battery cell group and the scooter battery module, without relying on glue or double-sided tape, and the shell design meets high-level waterproof standards, ensuring stable operation in harsh environments.

[0005] The present invention provides a battery cell group with balanced current collection, comprising: four brackets, two groups of 21700 battery cells, and two groups of nickel sheets; the 21700 battery cells are fixed by the screw column structure of the four brackets; the two groups of nickel sheets adopt a symmetrical balanced current collection design, and the overcurrent path resistance difference of each 21700 battery cell is ≤5%.

[0006] Furthermore, the four brackets include bracket A, bracket B, bracket C, and bracket D; the two groups of 21700 battery cells include a first group of 21700 battery cells and a second group of 21700 battery cells; the two groups of nickel sheets include a first group of nickel sheets and a second group of nickel sheets;

[0007] The first set of 21700 battery cells are fixed to the screw posts of brackets A and B using M2.3 self-tapping screws. The first set of nickel sheets are spot welded through the limit installation of brackets A and B to form bracket A / B battery module-1.

[0008] The second set of 21700 battery cells are fixed to the screw posts of brackets C and D using M2.3 self-tapping screws. The second set of nickel sheets are spot welded through the limit installation of brackets C and D to form bracket C / D battery module-2.

[0009] The A / B battery module-1 and the C / D battery module-2 are fixed to the screw columns of brackets B and C using M2.3 screws to form a 13S5P battery cell group.

[0010] Furthermore, the welding point of each nickel sheet in the two groups of nickel sheets is located in the limiting groove of each of the four brackets, and the distance between the welding point and the adjacent nickel sheet is ≥3 mm.

[0011] Furthermore, EVA foam and epoxy board are respectively attached to both sides of bracket A and bracket D.

[0012] A scooter battery module includes: a BMS motherboard, a battery compartment, 65 battery cells, and a battery cell group with a balanced current bus; the 65 battery cells and the battery cell group are compactly arranged and configured in a preset physical space of the battery compartment, and the physical space occupied by the battery cell group is the same as the physical space occupied by each of the 66 battery cells; the BMS motherboard is configured in the battery compartment.

[0013] Furthermore, the BMS mainboard is fixed to the battery cell group through the positioning columns and screw columns of bracket A, bracket B, bracket C, and bracket D, using M2.3 self-tapping screws. The distance between the BMS mainboard and the battery cell group is ≥2mm.

[0014] Furthermore, the left and right sides of the BMS protection plate are equipped with EVA foam, and the top and bottom sides are equipped with silicone waterproof rings;

[0015] The silicone waterproof ring integrates a leakage sensor, a microprocessor and an alarm. The leakage sensor is used to collect the ambient humidity according to the set collection cycle; the microprocessor determines the threshold of the ambient humidity. If it exceeds the set first humidity threshold for three consecutive times, the alarm is controlled to sound an alarm; if the ambient humidity is lower than the set second humidity threshold, the alarm is controlled to cancel the alarm.

[0016] Furthermore, the second nickel sheet in the first group of nickel sheets and the first nickel sheet in the second group of nickel sheets are connected in series and in parallel via the BMS mainboard; the second nickel sheet in the first group of nickel sheets is fixedly mounted and spot welded on bracket B; the first nickel sheet in the second group of nickel sheets is fixedly mounted and spot welded on bracket C;

[0017] The first nickel sheet in the first group of nickel sheets and the second nickel sheet in the second group of nickel sheets are routed in series and in parallel through the wire holes of bracket A, bracket B, bracket C, and bracket D, and the number of flying wires is ≤5; the first nickel sheet in the first group of nickel sheets is spot welded on bracket A for limiting installation; the second nickel sheet in the second group of nickel sheets is spot welded on bracket D for limiting installation.

[0018] Furthermore, the BMS mainboard has a built-in dynamic balancing algorithm. The balancing current is set to ≥100mA. The dynamic balancing algorithm performs the following steps:

[0019] Monitor the voltage of each battery cell in real time and calculate the average voltage of the two groups of batteries, as well as the maximum deviation between the battery cell voltage and the average voltage;

[0020] When the maximum deviation is greater than or equal to the set deviation threshold, active balancing is started and the balancing current is proportionally controlled to ensure that the balancing current is ≥100mA. The cells are sorted in descending order of deviation value and the first three cells with the largest deviation are selected for priority balancing to avoid excessive temperature rise caused by balancing multiple cells at the same time. Priority balancing is: cyclic balancing is performed according to the set balancing time and rotation interval.

[0021] Furthermore, the battery compartment is made of aluminum alloy and has a multi-layer protective structure inside; the protective structure includes an insulating lining, a buffer layer and a sealing strip.

[0022] Compared with the prior art, the present invention has the following advantages and beneficial effects: the battery cell group has a compact structure, and the balanced confluence design effectively reduces the voltage difference between the battery cells, thereby improving the safety and stability of the battery module; at the same time, the use of M2.3 screws for locking and fixing ensures a firm connection between the battery cell group and the BMS mainboard, reducing the risk of loose connection due to vibration or external force impact; in addition, the use of EVA foam and epoxy board further enhances the shock resistance and insulation performance of the battery module; and the leakage sensor, microprocessor and alarm integrated in the silicone waterproof ring can promptly issue an alarm when leakage occurs in the battery module, effectively avoiding safety hazards.

[0023] Other features and advantages of the present invention will be described in the following description, and in part will become apparent from the description, or will be understood by practicing the present invention. The purpose and other advantages of the present invention can be realized and obtained by the structures particularly pointed out in the written description and the accompanying drawings.

[0024] The technical solution of the present invention is further described in detail below through the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention. In the accompanying drawings:

[0026] Figure 1 It is a schematic diagram of the structure of a battery cell group with balanced current;

[0027] Figure 2 Schematic diagram of the connection structure between the battery cell, nickel sheet and bracket;

[0028] Figure 3 This is a schematic diagram of the scooter battery module structure. DETAILED DESCRIPTION

[0029] The preferred embodiments of the present invention are described below with reference to the accompanying drawings. It should be understood that the preferred embodiments described herein are only used to illustrate and explain the present invention, and are not used to limit the present invention.

[0030] The present invention provides a battery pack with balanced busbars, such as Figure 1 As shown, it includes: four brackets, two groups of 21700 battery cells, and two groups of nickel sheets; the 21700 battery cells are fixed by the screw column structure of the four brackets; the two groups of nickel sheets adopt a symmetrical balanced bus design, and the overcurrent path resistance difference of each 21700 battery cell is ≤5%.

[0031] The working principle of the above technical solution is as follows: the 21700 battery cells in the battery pack are fixed by the screw column structure of four brackets, ensuring the stability and structural strength of the battery pack; the two groups of nickel sheets adopt a symmetrical balanced confluence design, which makes the current more evenly distributed in the battery pack, effectively avoiding local overheating and excessive current problems; the strict control of the resistance difference of the overcurrent path of each 21700 battery cell (≤5%) further improves the working efficiency and safety of the battery pack; in actual operation, when the battery module needs to discharge, the current is evenly distributed to each battery cell through the nickel sheet, ensuring that each battery cell can discharge at a similar rate; similarly, during the charging process, the current can also flow back to each battery cell evenly through the nickel sheet, avoiding battery performance differences and safety hazards caused by uneven current distribution.

[0032] The beneficial effects of the above technical solution are: the solution provided in this embodiment can significantly improve the working efficiency and safety of the battery pack; the battery cells in the battery pack are fixed by a stable bracket structure, and the nickel sheet adopts a symmetrical and balanced confluence design, which makes the current distribution more uniform, thereby extending the service life of the battery cells and reducing the failure rate caused by local overheating or excessive current.

[0033] In one embodiment, Figure 2 As shown, the four brackets include bracket A, bracket B, bracket C and bracket D; the two groups of 21700 battery cells include a first group of 21700 battery cells and a second group of 21700 battery cells; the two groups of nickel sheets include a first group of nickel sheets and a second group of nickel sheets;

[0034] The first set of 21700 battery cells are fixed to the screw posts of brackets A and B using M2.3 self-tapping screws. The first set of nickel sheets are spot welded through the limit installation of brackets A and B to form bracket A / B battery module-1.

[0035] The second set of 21700 battery cells are fixed to the screw posts of brackets C and D using M2.3 self-tapping screws. The second set of nickel sheets are spot welded through the limit installation of brackets C and D to form bracket C / D battery module-2.

[0036] The A / B battery module-1 and the C / D battery module-2 are fixed to the screw columns of brackets B and C using M2.3 screws to form a 13S5P battery cell group.

[0037] The working principle of the above technical solution is as follows: each cell in the cell group is fixed and connected by a bracket and nickel sheets, achieving stable combination and power transmission between the cells; bracket A and bracket B jointly carry the first group of 21700 battery cells, and realize series or parallel connection between the battery cells through the first group of nickel sheets, forming bracket A / B battery module-1; similarly, bracket C and bracket D carry the second group of 21700 battery cells, connected by the second group of nickel sheets, forming bracket C / D battery module-2; these two modules are then connected by screws on brackets B and bracket C to form an integrated 13S5P battery group; in this battery group, the balancing bus design ensures that the voltage and current of each battery cell are balanced during operation, avoiding the degradation of battery module performance due to cell performance differences; the balancing bus system may include a balancing circuit and a bus bar. The balancing circuit is responsible for monitoring and adjusting the voltage of each battery cell to ensure that the voltage difference between the batteries is within the allowable range; the bus bar aggregates the power of the battery group and outputs it for use by the scooter battery module.

[0038] The beneficial effect of the above technical solution is that by adopting the solution provided by this embodiment, the battery cell group design not only improves the overall performance of the battery module, but also enhances its safety and reliability.

[0039] In one embodiment, the welding point of each nickel sheet in the two groups of nickel sheets is located in the limiting groove of each bracket in the four brackets, and the distance between the welding point and the adjacent nickel sheet is ≥3 mm.

[0040] The working principle of the above technical solution is as follows: the welding point is designed to be in the limiting groove of the bracket. Such a layout not only ensures the stability of the welding point, but also effectively prevents the risk of welding point damage or short circuit that may occur during the assembly and use of the battery module; at the same time, the spacing of ≥3mm between the welding point and the adjacent nickel sheet reduces the electrical interference or short circuit problems that may be caused by the close distance between the nickel sheets, further improving the safety and reliability of the battery module; when the battery cell group is working in the scooter battery module, the current is transmitted from the battery cell to the battery cell through the nickel sheet to form a complete circuit loop; and the welding point is the key node connecting the battery cell and the nickel sheet. Its stability and safety are directly related to the working efficiency of the entire battery module. By setting the welding point in the limiting groove of the bracket and strictly controlling the spacing between the welding point and the adjacent nickel sheet.

[0041] The beneficial effects of the above technical solution are as follows: by adopting the solution provided in this embodiment, the battery cell pack design ensures the stability and efficiency of the current during transmission, while also improving the service life and safety of the battery module.

[0042] In one embodiment, EVA foam and epoxy board are respectively attached to both sides of bracket A and bracket D.

[0043] The working principle of the above technical solution is as follows: EVA foam is mainly used for buffering and fixing between the battery cell group and the scooter battery module shell. It has good elasticity and shock absorption properties, and can effectively absorb the vibration and impact that the battery module may encounter during use, protecting the battery cell group from external forces, and ensuring the stability of current transmission and the safety of the battery module; while the epoxy board is used as an isolation layer between the battery cell group and the external environment due to its excellent insulation properties and mechanical strength. It can effectively prevent direct contact between the battery cell group and the shell, avoid the risk of electrical short circuit, and also provide a solid support structure for the battery cell group.

[0044] The beneficial effect of the above technical solution is that the solution provided by this embodiment not only enhances the overall stability of the battery module, but also further improves its safety and reliability.

[0045] A scooter battery module, such as Figure 3 As shown, it includes: a BMS mainboard, a battery compartment, 65 battery cells and a battery cell group with a balanced bus; the 65 battery cells and the battery cell group are compactly arranged in the preset physical space of the battery compartment, and the physical space occupied by the battery cell group is the same as the physical space occupied by each of the 66 battery cells; the BMS mainboard is configured in the battery compartment.

[0046] The working principle of the above technical solution is as follows: The BMS motherboard, as the core component of the battery management system, is responsible for monitoring, managing and protecting the battery cell group. It can detect key parameters such as voltage, current and temperature of each battery cell in real time to ensure the balance and safety of the battery cell group during the charging and discharging process. When abnormal parameters of a certain battery cell are detected, the BMS motherboard will quickly activate the protection mechanism, such as cutting off the power supply or adjusting the charging and discharging strategy to prevent the battery cell from overcharging, over-discharging or overheating, thereby extending the service life of the battery module; in addition, the battery cell group realizes balanced current distribution between the battery cells through the balanced convergence design. During the charging and discharging process, the balanced convergence device can automatically adjust the charging and discharging current of each battery cell to ensure the stability and efficiency of the overall performance of the battery cell group.

[0047] The beneficial effects of the above technical solution are as follows: adopting the solution provided by this embodiment not only improves the energy density and power output of the battery module, but also reduces the performance difference between battery cells and prolongs the cycle life of the battery module.

[0048] In one embodiment, the BMS mainboard is fixed to the battery cell group through the positioning columns and screw columns of bracket A, bracket B, bracket C, and bracket D, using M2.3 self-tapping screws, and the distance between the BMS mainboard and the battery cell group is ≥2mm.

[0049] The working principle of the above technical solution is as follows: the BMS motherboard ensures a stable connection with the battery cell group by fixing it, while maintaining an appropriate spacing, which is conducive to heat dissipation and preventing short circuits; during the operation of the scooter battery module, the BMS motherboard continuously monitors the status of the battery cell group, and obtains the voltage, current and temperature information of the battery cell group in real time through high-precision sensors and data acquisition circuits. After being processed by the microprocessor on the motherboard, this information is used to determine whether the working status of the battery cell group is normal. Once an abnormality is found, such as a battery cell with too high or too low voltage, too large current or too high temperature, the BMS motherboard will immediately activate the preset protection strategy, such as adjusting the charge and discharge current, cutting off the power supply or triggering an alarm to ensure the safe operation of the battery module; in addition, the balancing convergence device automatically adjusts the charge and discharge current between the battery cells under the monitoring of the BMS motherboard, further improving the overall performance and stability of the battery module.

[0050] The beneficial effects of the above technical solution are as follows: the solution provided by this embodiment can effectively avoid the performance degradation and safety hazards of the battery module caused by the imbalance between the battery cells in the battery pack, thereby extending the service life of the battery module; at the same time, through the real-time monitoring and protection strategy of the BMS motherboard, abnormal situations can be discovered and handled in the first time, significantly improving the safety and reliability of the battery module; in addition, the application of the balancing convergence device not only improves the overall performance of the battery module, but also enables the scooter battery module to maintain stable energy output in a complex and changeable riding environment, providing the scooter with long-lasting and stable power support.

[0051] In one embodiment, EVA foam is provided on both the left and right sides of the BMS protection plate, and silicone waterproof rings are provided on both the top and bottom sides;

[0052] The silicone waterproof ring integrates a leakage sensor, a microprocessor and an alarm. The leakage sensor is used to collect the ambient humidity according to the set collection cycle; the microprocessor determines the threshold of the ambient humidity. If it exceeds the set first humidity threshold for three consecutive times, the alarm is controlled to sound an alarm; if the ambient humidity is lower than the set second humidity threshold, the alarm is controlled to cancel the alarm.

[0053] The working principle of the above technical solution is: when the scooter battery module is in a complex and changeable riding environment, it will inevitably encounter rain, mud and other humid conditions. At this time, EVA foam, as a buffer and shockproof material, can effectively protect the BMS protection board from external impact. At the same time, its excellent sealing performance can also block water penetration to a certain extent. The silicone waterproof ring further enhances the waterproof effect. Its soft material and tight fitting design ensure that moisture cannot easily penetrate into the BMS protection board; the leakage sensor integrated on the silicone waterproof ring is like a pair of alert eyes that constantly monitors the humidity changes in the surrounding environment. Once the ambient humidity exceeds Within the preset safety range, the microprocessor will respond quickly and perform threshold judgment on the humidity values collected three times in a row. If the judgment result confirms that there is a risk of leakage, the microprocessor will immediately activate the alarm mechanism and issue a clear alarm prompt through the alarm to remind the user to take timely measures to avoid damage to the battery module due to moisture intrusion; on the contrary, if the ambient humidity gradually decreases to within the safety range, that is, less than the set second humidity threshold, the microprocessor will control the alarm to cancel the alarm and restore the normal monitoring state. This intelligent monitoring and alarm mechanism not only improves the safety performance of the scooter battery module, but also provides users with a more convenient and reliable use experience.

[0054] The beneficial effects of the above technical solution are as follows: the solution provided in this embodiment can significantly improve the adaptability and durability of the scooter battery module in complex and changeable environments; through the dual protection of EVA foam and silicone waterproof ring, the potential threat of the external humid environment to the BMS protection board is effectively isolated, greatly extending the service life of the battery module; at the same time, the integrated leakage sensor and intelligent monitoring and alarm mechanism realize real-time and accurate control of the battery module status. Once an abnormal situation is detected, it can respond quickly, thereby ensuring the safe and stable operation of the scooter battery module.

[0055] In one embodiment, the second nickel sheet in the first group of nickel sheets and the first nickel sheet in the second group of nickel sheets are connected in series and in parallel via the BMS mainboard; the second nickel sheet in the first group of nickel sheets is fixedly mounted and spot welded on bracket B; the first nickel sheet in the second group of nickel sheets is fixedly mounted and spot welded on bracket C;

[0056] The first nickel sheet in the first group of nickel sheets and the second nickel sheet in the second group of nickel sheets are routed in series and in parallel through the wire holes of bracket A, bracket B, bracket C, and bracket D, and the number of flying wires is ≤5; the first nickel sheet in the first group of nickel sheets is spot welded on bracket A for limiting installation; the second nickel sheet in the second group of nickel sheets is spot welded on bracket D for limiting installation.

[0057] The working principle of the above technical solution is as follows: the second nickel sheet in the first group of nickel sheets and the first nickel sheet in the second group of nickel sheets, after precise current confluence processing by the BMS mainboard, realize the series and parallel connection between the battery cells, thereby ensuring the balanced distribution of current inside the battery module. At the same time, the two nickel sheets are respectively limitedly installed and spot welded on bracket B and bracket C. This fixing method not only improves the stability of the connection, but also effectively avoids the problem of poor contact caused by vibration during the driving of the scooter; on the other hand, the first nickel sheet in the first group of nickel sheets and the second nickel sheet in the second group of nickel sheets are cleverly routed through the wire holes on bracket A, bracket B, bracket C, and bracket D, and finally realize the series and parallel confluence. This design greatly reduces the number of flying wires, making the wiring of the entire battery cell group simpler and more compact, which not only improves the space utilization of the battery module, but also helps to reduce the risk of short circuit caused by too many flying wires; the two nickel sheets are also limitedly installed and spot welded on the corresponding bracket A and bracket D, further enhancing the reliability of the connection;

[0058] The beneficial effects of the above technical solution are: by adopting the solution provided in this embodiment, efficient and balanced convergence of the battery cells inside the scooter battery module is achieved. During the use of the scooter, the battery module can stably provide power to ensure the normal driving of the scooter, while also providing users with a safer and more reliable use experience.

[0059] In one embodiment, the BMS mainboard has a built-in dynamic balancing algorithm, and the balancing current is set to ≥100mA. The dynamic balancing algorithm performs the following steps:

[0060] Monitor the voltage of each battery cell in real time and calculate the average voltage of the two groups of batteries, as well as the maximum deviation between the battery cell voltage and the average voltage;

[0061] When the maximum deviation is greater than or equal to the set deviation threshold, active balancing is started and the balancing current is proportionally controlled to ensure that the balancing current is ≥100mA. The cells are sorted in descending order of deviation value and the first three cells with the largest deviation are selected for priority balancing to avoid excessive temperature rise caused by balancing multiple cells at the same time. Priority balancing is: cyclic balancing is performed according to the set balancing time and rotation interval.

[0062] The working principle of the above technical solution is as follows: the BMS motherboard can monitor the voltage status of each battery cell in the scooter battery module in real time through the built-in dynamic balancing algorithm; first, the system will calculate the average value of all battery cell voltages, and find the battery cell with the largest deviation from the average voltage, and determine this maximum deviation value. Once this maximum deviation value exceeds the preset deviation threshold, it means that there is battery cell voltage imbalance in the battery module. At this time, the BMS motherboard will immediately start the active balancing function; during the active balancing process, the BMS motherboard will control the size of the balancing current according to the preset ratio to ensure that the balancing current is always maintained at a level of ≥100mA to ensure balancing efficiency; at the same time, in order to avoid the problem of excessive temperature rise caused by balancing multiple batteries at the same time, The system will select the first three cells with the largest deviations for priority balancing in the order of cell voltage deviation from large to small. This priority balancing strategy can not only effectively reduce the temperature difference inside the battery module, but also ensure that the balancing process is more efficient and safe. Specifically, priority balancing is a cyclic balancing according to the set balancing time and rotation interval. During the balancing time, the selected cells will transfer charge through a specific balancing circuit to achieve voltage balance. When the set balancing time is reached, the system will switch to the next cell for balancing until the first three cells with the largest deviations have completed a round of balancing. Then, the system will repeat this cyclic balancing process according to the set rotation interval to ensure continuous balance of the cell voltages inside the battery module.

[0063] The beneficial effects of the above technical solution are as follows: the solution provided in this embodiment can significantly improve the voltage balancing efficiency and safety of the scooter battery module; by real-time monitoring of the battery cell voltage and dynamic adjustment of the balancing current, it is ensured that each battery cell can be promptly and effectively balanced, thereby avoiding battery performance degradation and safety hazards caused by uneven battery cell voltage; in addition, through the priority balancing strategy, the temperature difference inside the battery module is further reduced, the battery service life is extended, and the overall performance and user experience of the scooter are improved.

[0064] In one embodiment, the battery compartment is made of aluminum alloy and has a multi-layer protective structure inside; the protective structure includes an insulating lining, a buffer layer and a sealing strip.

[0065] The working principle of the above technical solution is as follows: the battery compartment made of aluminum alloy has good heat dissipation performance and high mechanical strength, which can effectively protect the battery cell group from external impact and damage; the insulating lining is located between the battery cell group and the inner wall of the battery compartment, which plays the role of electrical isolation, preventing the battery cell group from causing safety accidents due to short circuit. The buffer layer is set around the battery cell group and is made of elastic material. It can absorb and disperse impact energy to further protect the safety of the battery cell group; the sealing strip is used to seal the battery compartment to prevent impurities such as moisture and dust from entering the battery compartment, ensuring that the battery cell group works in a good environment; when the scooter battery module is working, the battery cell group will generate a certain amount of heat. The aluminum alloy battery compartment can quickly conduct the heat away to maintain the temperature inside the battery module stable; at the same time, the multi-layer protective structure can effectively isolate the battery cell group from the external environment, preventing the battery cell group from being disturbed and damaged by the outside world.

[0066] The beneficial effects of the above technical solution are: adopting the solution provided by this embodiment not only improves the safety and reliability of the battery module, but also extends the service life of the battery.

[0067] Obviously, those skilled in the art may make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if such changes and modifications fall within the scope of the claims and their equivalents, the present invention is intended to include such changes and modifications.

Claims

1. A scooter battery module, characterized in that: include: The BMS motherboard, battery compartment, 65 battery cells, and a battery pack with balancing busbars; the 65 battery cells and the battery pack are compactly arranged within the preset physical space of the battery compartment, with the battery pack occupying the same physical space as each of the 66 battery cells; the BMS motherboard is configured within the battery compartment; The battery pack with balanced current includes: four brackets, two sets of 21700 battery cells, and two sets of nickel sheets; the 21700 battery cells are fixed by the screw column structure of the four brackets; The four brackets include bracket A, bracket B, bracket C, and bracket D; the two groups of 21700 battery cells include a first group of 21700 battery cells and a second group of 21700 battery cells; the two groups of nickel sheets include a first group of nickel sheets and a second group of nickel sheets; The first set of 21700 battery cells are fixed to the screw posts of brackets A and B using M2.3 self-tapping screws. The first set of nickel sheets are spot welded through the limit installation of brackets A and B to form bracket A / B battery module-1. The second set of 21700 battery cells are fixed to the screw posts of brackets C and D using M2.3 self-tapping screws. The second set of nickel sheets are spot welded through the limit installation of brackets C and D to form bracket C / D battery module-2. Secure the battery cell module-1 of bracket A / B and the battery cell module-2 of bracket C / D with M2.3 screws through the screw columns of bracket B and bracket C to form a battery cell group. The two sets of nickel sheets adopt a symmetrical balanced current bus design, and the difference in overcurrent path resistance of each 21700 battery cell is ≤5%; The second nickel sheet in the first group of nickel sheets and the first nickel sheet in the second group of nickel sheets are connected in series and in parallel via the BMS mainboard; the second nickel sheet in the first group of nickel sheets is fixedly mounted and spot welded on bracket B; the first nickel sheet in the second group of nickel sheets is fixedly mounted and spot welded on bracket C; The first nickel sheet in the first group of nickel sheets and the second nickel sheet in the second group of nickel sheets are routed in series and in parallel through the wire holes of bracket A, bracket B, bracket C, and bracket D, and the number of flying wires is ≤5; the first nickel sheet in the first group of nickel sheets is spot welded on bracket A for limiting installation; the second nickel sheet in the second group of nickel sheets is spot welded on bracket D for limiting installation.

2. A scooter battery module according to claim 1, characterized in that: The welding point of each nickel sheet in the two groups of nickel sheets is located in the limiting groove of each bracket in the four brackets, and the distance between the welding point and the adjacent nickel sheet is ≥3mm.

3. A scooter battery module according to claim 1, characterized in that: EVA foam and epoxy board are respectively attached to both sides of bracket A and bracket D.

4. The scooter battery module according to claim 1, characterized in that: The BMS mainboard is fixed to the battery cell group through the positioning columns and screw columns of bracket A, bracket B, bracket C, and bracket D, using M2.3 self-tapping screws. The distance between the BMS mainboard and the battery cell group is ≥2mm.

5. The scooter battery module according to claim 1, characterized in that: The left and right sides of the BMS protection plate are equipped with EVA foam, and the top and bottom sides are equipped with silicone waterproof rings; The silicone waterproof ring integrates a leakage sensor, a microprocessor and an alarm. The leakage sensor is used to collect the ambient humidity according to the set collection cycle; the microprocessor determines the threshold of the ambient humidity. If it exceeds the set first humidity threshold for three consecutive times, the alarm is controlled to sound an alarm; if the ambient humidity is lower than the set second humidity threshold, the alarm is controlled to cancel the alarm.

6. The scooter battery module according to claim 1, characterized in that: The BMS motherboard has a built-in dynamic balancing algorithm. The balancing current is set to ≥100mA. The dynamic balancing algorithm performs the following steps: Monitor the voltage of each battery cell in real time and calculate the average voltage of the two groups of batteries, as well as the maximum deviation between the battery cell voltage and the average voltage; When the maximum deviation is greater than or equal to the set deviation threshold, active balancing is started and the balancing current is proportionally controlled to ensure that the balancing current is ≥100mA. The cells are sorted in descending order of deviation value and the first three cells with the largest deviation are selected for priority balancing to avoid excessive temperature rise caused by balancing multiple cells at the same time. Priority balancing is: cyclic balancing is performed according to the set balancing time and rotation interval.

7. The scooter battery module according to claim 1, characterized in that: The battery compartment is made of aluminum alloy and has a multi-layer protective structure inside; the protective structure includes an insulating lining, a buffer layer and a sealing strip.

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