Werkzeugakkupack

Abstract

A tool battery pack comprising a housing assembly, a cell assembly, a pole piece holder, and a control device, wherein the housing assembly serves to accommodate the cell assembly, the pole piece holder, and the control device; wherein the control device is connected to the pole piece holder and the cell assembly; wherein the cell assembly comprises a plurality of unit cells and a cell holder, wherein the control device is provided on the cell holder;wherein the control device comprises a control board and a connecting element, characterized in that the connecting element comprises sheet-like detection elements for unit cells and connecting pole pieces, one end of the connecting pole piece being connected to the unit cell respectively, the unit cell detection element having a first connecting end and a second connecting end, the other end of the connecting pole piece being directly connected to the first connecting end, the first connecting end integrating a plurality of connecting pieces, the second connecting end being connected to the control board by welding.;

Description

Cross-reference to related applications

[0001] This application claims priority from Chinese patent application No. 202520348339.4, filed with the Chinese Patent Office on February 28, 2025, and entitled “Battery Pack,” Chinese patent application No. 202520561968.5, filed with the Chinese Patent Office on March 27, 2025, and Chinese patent application No. 202520561968.5, filed with the Chinese Patent Office on April 1, 2025, and entitled “Tool Battery Pack,” the entire contents of which are incorporated into this application by reference. Technical area

[0002] The embodiment of the application relates to the field of energy supply, in particular to a tool battery pack. Background technology

[0003] In the field of existing tool battery packs, a one- or two-parallel cell assembly is typically used as the basic unit, with power output realized through a group structure of the unit cells. The negative and positive terminals of each cell are welded with conductive electrodes made of nickel or copper-aluminum composite and electrically connected to the control board (BMS) via a separate wiring harness. Specifically, each cell corresponds to a set of separate wiring harnesses, one end of which is attached to the conductive pole piece by laser welding or resistance welding, and the other end is connected to the detection terminal of the control board via push-in terminals (such as JST, XH2.54, etc.), forming a multi-channel network for monitoring voltage, temperature, and internal resistance.

[0004] This conventional architecture presents significant technical inconsistencies: First, the number of wiring harnesses increases linearly with the number of cells, as the battery pack capacity increases. Taking a typical 18V / 5.0Ah power tool battery pack as an example, using 21700 cells with a 2-parallel and 5-series structure requires at least 10 groups of separate wiring harnesses (including redundant detection channels). The wire harness diameters generally range from AWG22 to AWG24 and occupy approximately 12%-15% of the battery pack's internal volume. This not only limits energy density improvements but also requires the enclosure structure design to accommodate complex cable slot alignment surfaces and terminal slots, resulting in a space-performance trade-off.

[0005] Second, high-frequency vibrations from power tools (up to 50 Hz or more, amplitude ±2 mm) under dynamic working conditions trigger the resonance effect of the wiring harness, which is particularly pronounced. The free end of the wiring harness easily rubs against the adjacent core sheath or metal bracket in an incompletely clamped state, leading to breakage of the insulating layer (for example, the wear rate of the PVC / PET wiring harness reaches 0.25 mm after 3,000 vibration cycles). 2 Statistics show that such micro-short-circuit failures caused by mechanical fatigue account for 38.6% of returned tool battery pack cases, and most of them occur in the area where the stress is concentrated and the bending radius of the wiring harness is less than 5D (where D is the wire diameter).

[0006] Furthermore, there are inherent weaknesses in the waterproof design of push-in terminals. Conventional solutions utilize silicone seals (hardness 50 ± 5 Shore A) through compression fit to protect against water ingress. However, with frequent insertion and removal (more than 200 insertion and removal cycles) or due to transverse shear force, relative displacement occurs between the metal pins and the seal material, reducing the interfacial sealing pressure and making it difficult to maintain the protection class. Content of the utility model

[0007] It is an object of embodiments of the present application to provide a tool battery pack that solves the problem of inherent deficiencies in the waterproof design of redundant detection channels and plug-in terminals of a tool battery pack.

[0008] A tool battery pack comprising a housing assembly, a cell assembly, a pole piece holder, and a control device, wherein the housing assembly serves to accommodate the cell assembly, the pole piece holder, and the control device; wherein the control device is connected to the pole piece holder and the cell assembly; wherein the cell assembly comprises a plurality of unit cells and a cell holder, wherein the control device is provided on the cell holder; wherein the control device has a control board and a connecting element, wherein the connecting element has sheet-like detection elements for unit cells and connecting pole pieces, wherein one end of the connecting pole piece is connected to the unit cell, respectively, wherein the unit cell detection element has a first connection end and a second connection end, wherein the other end of the connecting pole piece is directly connected to the first connection end,The first connection end integrates multiple connectors, and the second connection end is connected to the control board by welding. Compared with the loose structure of "discrete wiring harnesses + plug-in terminals" of conventional power tool battery packs, which poses the problem of redundant detection paths and design flaws of the power tool battery pack's plug-in terminals regarding waterproofness, this application replaces the discrete wiring harness by adopting the plate / sheet-shaped detection element for unit cells and integrates the N-cell detection paths into a single connector through the integrated layout of multiple pole pieces, thus realizing the advantages of power tool battery packs in terms of space utilization, dynamic reliability, signal accuracy, and environmental resistance. The reliability,The signal accuracy and environmental tolerance of the tool battery pack are comprehensively improved, making it particularly suitable for the high-vibration and high-humidity working conditions of industrial power tools.

[0009] Optionally, the second connection end has a first welding plate at least equal to the number of unit cells, each first welding plate being directly connected to the second connection end of the unit cell sensing element by a soldering process to form a separate electrical channel, which can eliminate the common grounding interference of the conventional wiring harness.

[0010] Optionally, the control board features a second weld plate that is at least equal to the number of first weld plates at the second connection end. By precisely matching the number of second weld plates on the control board with the first weld plates on the connector, the loose architecture of "discrete plug-in terminal + wiring harness" is upgraded to the integrated paradigm of "matrix of weld plates - rigid connection." This completely solves the problems of electrical failure and mechanical fatigue of the tool battery pack under high vibration and high humidity conditions.

[0011] Optionally, the area of ​​the first weld plate is less than or equal to the area of ​​the second weld plate. A smaller area of ​​the first weld plate allows it to fully adhere to the larger second weld plate, reducing the risk of potential short circuits between adjacent weld plates, thereby improving the safety and reliability of the circuit and ensuring good thermal conduction and electrical connection. At the same time, the smaller weld plate acts on the larger weld plate during thermal expansion, reducing the mechanical stress caused by thermal expansion and contraction, thereby reducing fatigue and potential cracking at the solder joints. This configuration increases the mechanical strength of the weld and improves the stability and durability of the joint.

[0012] Optionally, the first weld plate has at least one through-hole extending through the first weld plate, which increases the penetration ability of the solder through the through-hole during the soldering process, improving the mechanical strength and the strength of the conductive connection. The through-hole allows for better solder filling to form a more robust and better conductive connection.

[0013] Optionally, the ratio between the through-hole opening and the weld plate width of the first weld plate containing the opening is less than or equal to 1:2. By setting a ratio between the through-hole opening and the weld plate width of the first weld plate containing the opening that is less than or equal to 1:2, the solder penetration ability through the through-hole during the soldering process is increased, improving the mechanical strength and the strength of the conductive joint. The through-hole allows for better solder filling to form a more robust and better conductive joint.

[0014] Optionally, the minimum distance e between adjacent weld plates is greater than or equal to 0.2 mm and less than or equal to 2 mm. By specifying that the minimum distance e between adjacent weld plates is greater than or equal to 0.2 mm and less than or equal to 2 mm, the risk of short circuits due to solder bridges or contamination by conductive particles is effectively reduced, and welding defects caused by prestressing in the manufacturing process can also be reduced.During manufacturing and operation, increased spacing provides greater tolerance for errors in soldering and subsequent operations, increases overall circuit safety and reliability, prevents signal crosstalk, improves signal integrity and transmission efficiency, allowing each area of ​​the weld plate to effectively dissipate heat, avoiding excessive concentration of local overheating problems caused by increased weld plate spacing, allowing better heat diffusion and management.

[0015] Optionally, the distance f between the peripheral component and the adjacent first weld plate is greater than or equal to 1 mm and less than or equal to 25 mm. This allows the distance between the weld plate and the peripheral components to be increased, which helps reduce mutual interference from electromagnetic interference. This physical isolation can reduce signal coupling on the circuit board, improve signal integrity, and ensure more stable electrical performance. At the same time, the increased distance between the components and the weld plate reduces the risk of short circuits due to accidental contact or material bridging (e.g., solder overflow), and the risk of short circuits, resulting in a larger safety margin for production and subsequent operation of the device.Then, the larger distance improves the heat diffusion capabilities of the circuit board, so that heat can be more effectively dissipated from the high-temperature zone to avoid local overheating and heat buildup problems.

[0016] Optionally, the distance f between the peripheral component and the adjacent second welding plate is greater than or equal to 1 mm and less than or equal to 25 mm. This allows the distance between the welding plate and the peripheral components to be increased, which helps reduce mutual interference from electromagnetic interference. This physical isolation can reduce signal coupling on the circuit board, improve signal integrity, and ensure more stable electrical performance. At the same time, the increased distance between the components and the welding plate reduces the risk of short circuits due to accidental contact or material bridging (e.g., solder overflow), and the risk of short circuits, resulting in a larger safety margin for production and subsequent operation of the device.Then, the larger distance improves the heat diffusion capabilities of the circuit board, so that heat can be more effectively dissipated from the high-temperature zone to avoid local overheating and heat buildup problems.

[0017] Optionally, the first welding plate has a tinning thickness of 0.05-0.15 mm, which can be used to improve the galvanic isolation effect of the soldering area by reducing excessive solder flow during the soldering process and reducing the risk of solder bridges and short circuits.

[0018] Optionally, the second welding plate has a tinning thickness of 0.05-0.15 mm, which can be used to improve the galvanic isolation effect of the soldering area by reducing excessive solder flow during the soldering process and reducing the risk of solder bridges and short circuits. Illustration of the attached drawings

[0019] One or more embodiments are illustrated by way of example with reference to the figures of the accompanying drawings, wherein the exemplary figures do not represent a limitation of the embodiments. Fig. 1 is a three-dimensional plan view of a tool battery pack provided by an embodiment of the present application; Fig. 2 is a bottom three-dimensional view of a tool battery pack provided by an embodiment of the present application; Fig. 3 is a view of the internal structure of a tool battery pack provided by an embodiment of the present application; Fig. 4 is an exploded diagram of the internal structure of a tool battery pack provided by an embodiment of the present application; Fig. 5 is a cross-sectional view of a unit cell provided by an embodiment of the present application; Fig. 6 is a three-dimensional view of a first end surface of a water sealing plate of a tool battery pack provided by an embodiment of the present application; Fig. 7 is a three-dimensional view of a second end surface of a water sealing plate of a tool battery pack provided by an embodiment of the present application; Fig. 8 is a partially enlarged sectional view of a water sealing plate of a tool battery pack at location A provided by an embodiment of the present application; Fig. 9 shows the partial assembly of a waterproofing plate, a waterproofing layer, a cell holder, and a unit cell according to an embodiment of the present application; Fig. 10 is a partial sectional view of the internal structure of a tool battery pack provided by an embodiment of the present application, with the waterproofing plate and the waterproofing layer hidden; Fig. 11 is a partial three-dimensional perspective view of an output electrode holder provided by an embodiment of the present application; Fig. 12 is a front view of an electrode holder provided by an embodiment of the present application; Fig. 13 is an internal structural view of the tool battery pack provided by an embodiment of the present application; Fig. 14 is a three-dimensional view of a connecting element provided by an embodiment of the present application; Fig. 15 is a front view of the first welding holder provided by an embodiment of the present application; Fig. 16 is a front view of the second welding holder provided by an embodiment of the present application; Fig. 17 is a graph of temperature change data of a 60V cell and cell end area in a 30A discharge mode provided by an embodiment of the present application. Specific embodiments

[0020] In order to clarify the purpose, technical solutions, and advantages of the embodiments of the present application, the various embodiments of the present application are described in detail below in conjunction with the accompanying drawings. A person skilled in the art will appreciate that in the various embodiments of the present application, certain technical details are disclosed merely for clarity. Even without these technical details, as well as without various variations and modifications based on the following embodiments, the technical solution to be protected by the present application can be achieved. The following embodiments are divided for the sake of simplicity and do not represent a limitation on the specific configuration of the present application.Each embodiment may be combined with or refer to any other, provided they do not contradict each other.

[0021] In the current state of the art, tool battery packs typically use a single or double parallel cell assembly as the base unit, with power output realized through a group structure of the unit cells. The negative and positive terminals of each cell are welded with conductive electrodes made of nickel or copper-aluminum composite and electrically connected to the control system (BMS) via a separate wiring harness. Specifically, each cell corresponds to a set of separate wiring harnesses, one end of which is attached to the conductive pole piece by laser welding or resistance welding, and the other end is connected to the detection terminal of the control system board via push-in terminals (such as JST, XH2.54, etc.), forming a multi-channel network for monitoring voltage, temperature, and internal resistance.

[0022] This conventional architecture presents significant technical inconsistencies: First, the number of wiring harnesses increases linearly with the number of cells, as the battery pack capacity increases. Taking a typical 18V / 5.0Ah power tool battery pack as an example, using 21700 cells with a 2-parallel and 5-series structure requires at least 10 groups of separate wiring harnesses (including redundant detection channels). The wire harness diameters generally range from AWG22 to AWG24 and occupy approximately 12%-15% of the battery pack's internal volume. This not only limits energy density improvements but also requires the enclosure structure design to accommodate complex cable slot alignment surfaces and terminal slots, resulting in a space-performance trade-off.

[0023] Second, high-frequency vibrations from power tools (up to 50 Hz or more, amplitude ±2 mm) under dynamic working conditions trigger the resonance effect of the wiring harness, which is particularly pronounced. The free end of the wiring harness easily rubs against the adjacent core sheath or metal bracket in an incompletely clamped state, leading to breakage of the insulating layer (for example, the wear rate of the PVC / PET wiring harness reaches 0.25 mm after 3,000 vibration cycles). 2 Statistics show that such micro-short-circuit failures caused by mechanical fatigue account for 38.6% of returned tool battery pack cases, and most of them occur in the area where the stress is concentrated and the bending radius of the wiring harness is less than 5D (where D is the wire diameter).

[0024] Furthermore, there are inherent weaknesses in the waterproof design of push-in terminals. Conventional solutions utilize silicone seals (hardness 50 ± 5 Shore A) through compression fit to protect against water ingress. However, with frequent insertion and removal (more than 200 insertion and removal cycles) or due to transverse shear force, relative displacement occurs between the metal pins and the seal material, reducing the interfacial sealing pressure and making it difficult to maintain the protection class.

[0025] The inventor of this application discovered the above-mentioned defects and analyzed the causes of the defects by examining the overtemperature of the cells of power tool battery packs, the internal temperature of the thermal runaway cells, and the overall heat transfer of the battery pack in the prior art. This cleverly overcomes the volume of the power tool battery pack and the low production efficiency of the battery pack by constructing the water sealing element and appropriately designing the structure and materials. At the same time, it can provide rapid pressure relief for the thermal runaway cells, preventing the secondary triggering of thermal runaway and other problems, and implementing a lightweight, efficient, and safe insulation solution.

[0026] An embodiment of the present application is described in more detail below in conjunction with the accompanying drawings: With reference to Fig. 1- Fig. 17 discloses a tool battery pack comprising a housing assembly 1, a cell assembly 2, a pole piece holder 3 and a control device 4;

[0027] The housing assembly 1 has a first cooling opening 11, a holder seat (not shown), an opening 13, and a second cooling opening 14. The housing assembly 1 is used to accommodate the cell assembly 2, the pole piece holder 3, and the control device 4; the opening 13 is arranged corresponding to the location of the pole piece holder 3 in the housing assembly 1 so that the tool pole piece penetrates it and connects to the pole piece holder 3.wherein a second cooling opening 14 is arranged on the side of the battery pack with the opening 13, wherein the first cooling opening 11 and the second cooling opening 14 are provided opposite each other on the surface of the housing assembly 1, wherein the first cooling opening 11 is an air inlet, while the second cooling opening 14 is an air outlet, wherein a linear air channel is formed by the arrangement of the first cooling opening 11 and the second cooling opening 14, so that such a direct ventilation path helps the airflow to flow through the battery pack more efficiently, thereby ensuring that the internal temperature of the battery pack is always kept within a safe range, which greatly improves the heat dissipation efficiency of the battery pack and reduces the risk of explosion caused by cell overheating;wherein holder seats (not shown) are provided on at least one side of the housing assembly 1 for securing the cell assembly 2 to prevent movement of the cell holder 22 within the housing assembly 1; wherein the total area of ​​the first cooling opening 11 is larger than the total area of ​​the second cooling opening 14, wherein the air flow enters the housing assembly 1 through the first cooling opening 11 and is then discharged from the second cooling opening 14, wherein the first cooling opening 11 has a larger area which promotes the introduction of more cold air so that the cold air can fully come into contact with the cell assembly 2;

[0028] In one embodiment, the housing assembly 1 also includes a third cooling opening 15, wherein the third cooling opening 15 is arranged on a different side of the housing assembly 1 than the side where the first cooling opening 11 and the second cooling opening 14 are located, so that the air flow can enter the battery pack from that side. The air flow passing through the third cooling opening 15 and the air flow passing through the first cooling opening 11 converge into a single air flow, which is discharged from the second cooling opening 14. With the addition of a third cooling opening 15, the air flow can enter the battery pack in different directions, so that the heat of the cell assembly 2 can be distributed more evenly, thereby avoiding the phenomenon of local overheating.Converging the airflow inside can cover the cell surface more comprehensively and efficiently, maintaining overall heat balance and further enhancing the heat dissipation capacity of the battery pack. This not only increases air circulation and improves the efficiency of internal heat exchange, but also allows the battery pack to fully dissipate heat through other inlet ports even if one cooling port is partially blocked due to external factors, thus ensuring the reliability of the cooling system. This heat dissipation method, with multiple inlet ports and a single outlet port, contributes to a faster reduction of the cell surface temperature.

[0029] In one embodiment, the housing assembly 1 also includes a third cooling opening 15, wherein the third cooling opening 15 is arranged on any one of the two opposite sides of the housing assembly 1 other than the side where the first cooling opening 11 and the second cooling opening 14 are located, so that the airflow can enter the battery pack from this opposite side. The airflow passing through the third cooling opening 15 and the airflow passing through the first cooling opening 11 form a single airflow that is discharged from the second cooling opening 14. With the addition of a third cooling opening 15, the airflow can enter the battery pack in different directions, so that the heat of the cell assembly 2 can be distributed more evenly, thereby avoiding the phenomenon of local overheating.Converging the airflow inside can cover the cell surface more comprehensively and efficiently, maintaining overall heat balance and further enhancing the heat dissipation capacity of the battery pack. This not only increases air circulation and improves the efficiency of internal heat exchange, but also allows the battery pack to fully dissipate heat through other inlet ports even if one cooling port is partially blocked due to external factors, thus ensuring the reliability of the cooling system. This heat dissipation method, with multiple inlet ports and a single outlet port, contributes to a faster reduction of the cell surface temperature.

[0030] In one embodiment, the total area of ​​the third cooling opening 15 is less than or equal to the total area of ​​the second cooling opening 14, thereby solving the problem of localized overheating caused by a single airflow direction. Airflow in the lateral or other directions can flow sufficiently to ensure uniform heat dissipation throughout all parts of the cell, thus avoiding performance losses or risks due to locally high temperatures.The refined arrangement of the cooling holes can better control the temperature gradient in different areas of the device, and the arrangement with multiple inlet holes and one outlet hole makes it possible to ensure sufficient airflow and heat dissipation in the remaining cooling holes when one of the cooling holes fails due to external blockage or other problems, thus ensuring the continuity and reliability of the system.

[0031] In one embodiment, the total area of ​​the third cooling opening 15 is larger than the total area of ​​the second cooling opening 14, thereby solving the problem of localized overheating caused by a single airflow direction. Airflow in the lateral or other directions can flow sufficiently to ensure uniform heat dissipation in all parts of the cell, thus avoiding performance losses or risks due to locally confined high temperatures.The refined arrangement of the cooling holes can better control the temperature gradient in different areas of the device, and the arrangement with multiple inlet holes and one outlet hole makes it possible to ensure sufficient airflow and heat dissipation in the remaining cooling holes when one of the cooling holes fails due to external blockage or other problems, thus ensuring the continuity and reliability of the system.

[0032] In one embodiment, the second cooling opening 14 is provided in a central area on one side of the housing assembly 1 with an opening 13, this side facing the first cooling opening 11, so that the airflow can cover the surface of the cell assembly 2 more evenly. Distributing the airflow from the center to the periphery reduces the problem of local heat concentration and contributes to maintaining a uniform temperature distribution inside the battery pack.

[0033] In one embodiment, the second cooling opening 14 is provided near the opening 13 in a central area on one side of the housing assembly 1 with an opening 13, which side faces the first cooling opening 11, so that the airflow can cover the surface of the cell assembly 2 more evenly. Distributing the airflow from the center to the periphery reduces the problem of local heat concentration and contributes to maintaining a uniform temperature distribution inside the battery pack.

[0034] In one embodiment, the housing assembly 1 has a locking position 16. The housing assembly 1 is used to lock the battery pack to prevent movement of the battery pack. The second cooling opening 14 is provided in a central region on a side of the housing assembly 1 with an opening 13 or between the opening 13 and the locking position 16, this side facing the first cooling opening 11, so that the airflow can cover the surface of the cell assembly 2 more evenly. The distribution of the airflow, which spreads from the center to the periphery, reduces the problem of local heat concentration and contributes to maintaining a uniform temperature distribution inside the battery pack.

[0035] In one embodiment, the housing assembly 1 is a 2-split mold combination, wherein the housing assembly 1 is constructed as a concave housing with openings on the top or on both sides, wherein the end caps are connected to the housing from the opening side; wherein the housing assembly 1 is a 3-split mold combination, wherein the housing assembly 1 is constructed as a one-piece, continuously split housing with openings on opposite sides, wherein the end caps are connected to the housing from the openings; wherein the housing assembly 1 is a 4-split mold combination, wherein the housing assembly 1 is constructed as a continuously split housing with openings on opposite sides, wherein the housing is attachable at the top and bottom, wherein the end caps are connected to the housing from the openings; wherein the housing assembly 1 is assembled without particular restriction.

[0036] In one embodiment, the housing assembly 1 further comprises a water outlet opening 113, wherein the water outlet opening 113 is provided on at least one side other than the surface of the battery pack on which the opening 13 is located, in order to drain water entering the housing assembly 1.

[0037] As in Fig. As shown in Figure 4, the cell assembly 2 comprises a unit cell 21, a cell holder 22, a waterproofing layer 23 and a waterproofing element 24.

[0038] The unit cell 21 is a cylindrical cell with a first cell end face 211 and a second cell end face 212.

[0039] With reference to Fig. 5, in one embodiment, the first cell end surface 211 has a positive pole end surface 2111 and the positive pole end surface 2111 is a flat end surface.

[0040] With reference to Fig. 5, in one embodiment, the first cell end face 211 has a positive pole end face 2111 and the positive pole end face 2111 has a cap end face 21111, the cap end face 21111 protruding outwardly from the positive pole end face 2111.

[0041] With reference to the Fig. 5 and Fig. 9, in one embodiment, the first cell end face 211 has a positive terminal end face 2111 and also a negative terminal end face 2112. A separator 2113 is provided between the negative terminal end face 2112 and the positive terminal end face 2111 to isolate the positive electrode from the negative electrode to prevent short circuiting. At the first cell end face 211, the exposed hole 222 exposes the first edge, with the edge of the negative terminal end face 2112 near the central axis of the unit cell 21 being the first edge, and the projection distance C between the first edge and the edge within the exposed hole 222 being greater than or equal to 0.1 mm. With a distance between the exposed hole 222 and the first edge, not only is the insulating insulation structurally improved, but also the waterproofing layer 23 is allowed to cover the negative terminal end face 2112 and the separator 2113.Once the separator 2113 breaks or fails due to aging, the waterproofing layer 23 becomes an additional barrier layer that prevents water vapor from penetrating the cell. At the same time, the waterproofing layer 23 covers the negative terminal end face 2112 and the exposed hole 222, preventing water vapor from penetrating the cell end face along its length from the mounting gaps of the receiving slot 221 and further from contacting the positive terminal end face 2111 and the negative terminal end face 2112, thus preventing a potential short circuit.

[0042] With reference to Fig. 4, the cell holder 22 has a receiving slot 221, an exposed hole 222, a first end 223, a second end 224, wherein the first end 223 of the cell holder 22 has a receiving slot 221 that receives the unit cell 21, wherein one end of the receiving slot 221 has a groove into which the unit cell 21 projects, wherein the other end of the receiving slot 221 has an exposed hole 222 that extends through the cell holder 22, wherein the area within the exposed hole 222 is smaller than the cross-sectional area of ​​the receiving slot 221 that is parallel to the exposed hole 222, wherein the area of ​​the exposed hole 222 is smaller than the maximum area of ​​the first cell end surface 211 that extends into the receiving slot 221, wherein the shape of the exposed hole 222 has a rounded shape, a includes, but is not limited to, oval shape, square shape and other shapes;wherein the cell holder 22 is securely attached to the holder seat within the housing assembly 1 by means of, but not limited to, a welded or screwed connection to provide additional structural support and protection against vibrations;

[0043] With reference to Fig. 10, in one embodiment, the cell holder 22 includes a limiting portion 225 that cooperates with the holder seat, the limiting portion 225 including a locking element (not shown), the locking element (not shown) being in a form that includes, but is not limited to, a structural locking shape, the locking element (not shown) being a screw hole, or being screwed into place by a screw, or the locking element (not shown) being a first mortise and tenon structure and being attached to the housing assembly 1 by a second mortise and tenon structure by snapping it in, or by welding the limiting portion 225 to the housing assembly 1, or by locking it by gluing or other methods to ensure that the cell holder 22 does not move within the housing assembly 1.

[0044] With reference to Fig. 9, in one embodiment, the hole height D of the exposed hole 222 is greater than or equal to 0.5 mm, less than or equal to 2.5 mm. By setting the hole height D of the exposed hole 222 to greater than or equal to 0.5 mm, an effective support strength for the unit cell 21 can be achieved, preventing the position of the unit cell 21 from shifting due to vibration or other external forces during normal use, thus improving the overall mechanical stability and safety of the battery pack. Since it is less than or equal to 2.5 mm, the use of unnecessary materials can be avoided while strengthening the support force, thereby optimizing the weight of the battery pack and further improving energy efficiency and endurance performance. When designing the height range, the utilization rate of the cell's internal space is also taken into account.Based on safe mechanical support, the appropriate setting of the height inside the hole avoids unnecessary occupancy of the effective space of the battery pack, so that the battery pack can maximize the capacity and energy density within the limited space.

[0045] The waterproofing layer 23 is provided at the second end 224 of the cell holder 22 by an adhesive or vacuum deposition process. The waterproofing layer 23 covers the first cell end face 211 and the second cell end face 212 of the unit cell 21 to prevent a short circuit caused by contact between the first cell end face 211 and the second cell end face 212, and the outside water vapor.

[0046] With reference to the Fig. 6 to Fig. 10, the waterproofing member 24 is provided at a second end 224 of the cell holder 22, the waterproofing member 24 having a first end surface 241 remote from the cell holder 22 and a second end surface 242 proximate the cell holder 12, and at least a portion of the waterproofing layer between the second end surface 242 and the cell holder 12. The addition of the waterproofing member 24 eliminates the need to wait for the waterproofing layer to dry for subsequent assembly work after covering the waterproofing layer 23 on the cell holder 22, which greatly improves production line efficiency, reduces waiting time, and improves production flexibility and responsiveness.

[0047] With reference to Fig. 9, in one embodiment, the first end face 241 has a first convex surface 2411 at the exposed hole 222, which protrudes toward the end face of the unit cell 21, and the second end face 242 is a flat surface. The water sealing member 24 has a first convex surface 2411 at the position of the exposed hole 222, and the water sealing member 24 is formed in the weak region of the exposed hole 222. When the cell has an abnormal overtemperature, it usually has a high-voltage and high-temperature fire in the region of the first cell end face 211. At this time, the abnormal unit cell 21 can quickly break through the water sealing plate in the weak region, thereby providing a safe pressure relief mechanism to prevent the adjacent unit cell 21 or the adjacent cell assembly 2 from being affected, so that continuous deflagration occurs.

[0048] With reference to Fig. 9, in one embodiment, the first end surface 241 has a first convex surface 2411 at the exposed hole 222, which protrudes toward the end surface of the unit cell 21, and the second end surface 242 is a flat surface, wherein the distance b between the first convex surface 2411 and the second end surface 242 is greater than 0.3 mm and less than or equal to 3 mm. By setting the range of the distance b between the first convex surface 2411 and the second end surface 242, the thickness of the weak area can be controlled as much as possible to be easily broken. At the same time, it effectively prevents the problem of the waterproofing layer being broken due to improper operation during the pressing process, and ensures that it simultaneously provides waterproof protection and a clear and controlled safe pressure relief channel for abnormal conditions such as high pressure and high temperature.In addition, by clarifying the range of b, the thickness of the weak point area can be maintained in the manufacturing process, which not only ensures quality control in mass production, but also can improve the stability of the production process.

[0049] In one embodiment, the second end surface 242 is not planar, and the second end surface 242 has a second convex surface 2421 at the exposed opening 222 protruding toward the end surface of the unit cell 21, wherein the distance a-2 between the second convex surface 2421 and the positive terminal end surface 2111 is greater than or equal to 0.1 mm, or the distance a-1 between the second convex surface 2421 and the cap end surface 21111 is greater than or equal to 0.1 mm. By setting the range of a-1 and a-2, the thickness of the waterproofing layer in the weak area can be controlled as much as possible under effective waterproofing protection, thereby providing a clear and controlled safe pressure relief channel for high pressure, high temperature, and other abnormal situations.In addition, by clarifying the range of a-1 and a-2, the thickness of the weak point area can be maintained in the manufacturing process, which not only ensures quality control in mass production, but also can improve the stability of the production process.

[0050] In one embodiment, the second end surface 242 is not planar, and the second end surface 242 has a second convex surface 2421 at the exposed opening 222 protruding toward the end surface of the unit cell 11, wherein the distance a-2 between the second convex surface 2421 and the positive terminal end surface 2111 is greater than or equal to 0.1 mm or less than 2 mm, or the distance a-1 between the second convex surface 2421 and the cap end surface 21111 is greater than or equal to 0.1 mm or less than 2 mm. By setting the range of a-1 and a-2, the thickness of the waterproofing layer in the weak area can be controlled as much as possible under the effective waterproofing protection, thereby providing a clear and controlled safe pressure relief channel for high pressure, high temperature, and other abnormal situations.In addition, by clarifying the range of a-1 and a-2, the thickness of the weak point area can be maintained in the manufacturing process, which not only ensures quality control in mass production, but also can improve the stability of the production process.

[0051] In one embodiment, the second end face 242 has a second convex surface 2421 at the exposed opening 222, which protrudes toward the end face of the unit cell 21, wherein the distance between the second convex surface 2421 and the positive terminal end face 2111 is greater than or equal to 0.5 mm, less than 1 mm, or the distance a-1 between the second convex surface 2421 and the cap end face 21111 is greater than or equal to 0.5 mm, less than 1.5 mm. By setting the range of a-1 and a-2, the thickness of the waterproofing layer in the weak area can be controlled as much as possible under the effective waterproofing protection, thereby providing a clear and controlled safe pressure relief channel for high pressure, high temperature, and other abnormal situations.In addition, by clarifying the range of a-1 and a-2, the thickness of the weak point area can be maintained in the manufacturing process, which not only ensures quality control in mass production, but also can improve the stability of the production process.

[0052] In one embodiment, the second end face 242 has a second convex surface 2421 at the exposed opening 222, which protrudes toward the end face of the unit cell 11, wherein the distance a-2 between the second convex surface 2421 and the positive terminal end face 2111 is greater than or equal to 0.3 mm, less than or equal to 0.8 mm, or the distance a-1 between the second convex surface 2421 and the cap end face 21111 is greater than or equal to 0.3 mm, less than or equal to 1.2 mm. By setting the range of a-1 and a-2, the thickness of the waterproofing layer in the weak area can be controlled as much as possible under the effective waterproofing protection, thereby providing a clear and controlled safe pressure relief channel for high pressure, high temperature, and other abnormal situations.In addition, by clarifying the range of a-1 and a-2, the thickness of the weak point area can be maintained in the manufacturing process, which not only ensures quality control in mass production, but also can improve the stability of the production process.

[0053] With reference to Fig. 17, in one embodiment, the water sealing element 24 is a non-metallic material having a thermal softening temperature greater than or equal to 90°. As shown in Fig. As shown in Figure 17, the temperature rise of the cell end face of the 60V unit cell 21 during the 30A discharge process is approximately 60°C. As the current increases, the temperature rise of the cell end face also increases. When the cell temperature exceeds abnormal values ​​during the charge and discharge process, a high-voltage and high-temperature fire usually occurs in the region of the first cell end face 211 to protect the unit cell 21. At this time, the temperature of the cell end face is usually above 100°C. Since the water seal member 24 is a non-metallic material with a thermal softening temperature greater than or equal to 90°C, the water seal member 24 may soften spontaneously during the heating process of the abnormal unit cell 21.At this time, the abnormal unit cell 21 can break through the water sealing element in the weak area more quickly, thereby providing a safe pressure relief mechanism to avoid continuous deflagration affecting the adjacent unit cell 21 or the adjacent cell assembly 2. At the same time, in order to achieve a stable and effective waterproof effect, it cannot be affected by temperature during the heating process of the normal unit cell 21.

[0054] In one embodiment, the waterproofing member 24 is ABS\PC\PP\PE\Nylon\PA\GF. By setting the waterproofing member 24 as ABS\PC\PP\PE\Nylon\PA\GF, the waterproofing member 24 can soften itself during the heating process of the abnormal unit cell 21. At this time, the abnormal unit cell 21 can break through the waterproofing member in the weak area more quickly, thereby providing a safe pressure relief mechanism to prevent continuous deflagration from affecting the adjacent unit cell 21 or the adjacent cell assembly 2. At the same time, to achieve a stable and effective waterproofing effect, it can be unaffected by temperature during the heating process of the normal unit cell 21.

[0055] In one embodiment, the water sealing member 24 is a uniform-thickness water sealing plate having a thickness greater than or equal to 0.3 mm and less than or equal to 3 mm. The water sealing member 24 has a first convex surface 2411 and a second convex surface 2421 at the exposed hole 222, which protrude toward the end face of the unit cell 21. The convex surface 2411 and the second convex surface are formed in the weak region of the exposed hole 222. When the cell experiences abnormal overtemperature, it typically experiences a high-voltage and high-temperature fire in the region of the first cell end face 211.At this time, the abnormal unit cell 21 can quickly break through the water seal plate in the weak area, thereby providing a safe pressure relief mechanism to avoid affecting the adjacent unit cell 21 or the adjacent cell assembly 2, so that continuous deflagration occurs.

[0056] In one embodiment, the water sealing member 24 is a water sealing plate with uneven thickness, wherein the thickness of the water sealing member 24 at the exposed hole 222 is less than the thickness of the water sealing member 24 outside the exposed hole 222, and the water sealing member 24 is formed in the weak region of the exposed hole 222. When the cell experiences an abnormal overtemperature, it typically exhibits a high-voltage and high-temperature fire in the region of the first cell end face 211. At this time, the abnormal unit cell 21 can quickly break through the water sealing plate in the weak region, thereby providing a safe pressure relief mechanism to prevent the adjacent unit cell 21 or the adjacent cell assembly 2 from being affected, so that continuous deflagration occurs.

[0057] With reference to Fig. 4 In one embodiment, the water seal member 24 has a positioning member 226, wherein the positioning member 226 is a positioning hole, wherein the positioning post is provided in the cell holder 22, wherein the positioning post has a size of 1 mm-10 mm, which enables effective positioning.

[0058] In one embodiment, the water seal member 24 has a positioning member 226, wherein the positioning member 226 is a positioning post, wherein the positioning post has a size of 0.5 mm-2 mm, wherein the positioning hole is provided in the cell holder 22, wherein the positioning hole can accommodate some or all of the positioning;

[0059] In one embodiment, the water seal member 24 forms a limited fit to the cell holder 22. Embodiments include, but are not limited to, snap-fit ​​structural connections, welding, adhesive bonding, and other forms of process connection that are not limited to a mortise and tenon structure.

[0060] With reference to Fig. 10 - Fig. 12, the pole piece holder 3 has a terminal assembly 32, a terminal mounting seat 33, the terminal mounting seat 33 having a guide slot 331, a mounting end 332, and a water sealing space 333, the guide slot 331 being used to guide the tool pole piece in the correct insertion direction to avoid a short circuit caused by the installation error, and at the same time still being used to stabilize the tool pole piece to ensure that it is effectively connected to the control device 4; the mounting end 332 being used for firmly connecting to the control device 4.The water sealing space 333 includes a first water sealing space 3331, a second water sealing space 3332, wherein the first water sealing space 3331 is a mounting gap between the terminal mounting seat 33 and the terminal assembly 32 when the terminal mounting seat 33 is limited to the terminal assembly 32, wherein the second water sealing space 3332 is a mounting gap between the terminal mounting seat 33 and the control device 4, wherein the second water sealing space 3332 has at least one inlet opening 33321, wherein the inlet opening 33321 is arranged between the terminal mounting seat 33 in the control device 4.The position of the inlet opening 33321 is designed to facilitate the waterproofing material's rapid and even penetration into and filling the second waterproofing chamber 3332 during operation, achieving efficient waterproofing during assembly and maintenance and maintaining the safe operation of the control device for a long time. Completely filling the second waterproofing chamber 3332 provides a basic waterproofing barrier for the terminal assembly 32, protecting the internal structure from moisture and contaminants that could cause the control board to malfunction.

[0061] In one embodiment, the fixing end 332 has a height of greater than or equal to 0.5 mm and less than or equal to 3 mm in a columnar shape, the first end of the fixing end 332 being connected to the terminal fixing seat 33, the second end being connected to the control device 4, the fixing end 332 supporting the terminal fixing seat 33 so that the terminal fixing seat 33 is not in contact with the control device 4, the second waterproof space 3332 being the projection area from the terminal fixing seat 33 in the control device 4, the terminal fixing seat 33 being located in the non-contact space between control devices 4.

[0062] In one embodiment, the terminal fixing seat 33 has a fixing end 332 in a protruding shape on the side near the control device 4, the fixing end 332 being connected to the control device 4, the fixing end 332 supporting the terminal fixing seat 33 so that the terminal fixing seat 33 is not in contact with the control device 4, the second waterproof space 3332 forming the projection area of ​​the terminal fixing seat 33 in the control device 4, the terminal fixing seat 33 being located in a non-contact space between control devices 4.

[0063] In one embodiment, the waterproofing material of the first waterproofing space 3331 and the second waterproofing space 3332 is encapsulated in a single molded part by vacuum deposition, wherein the height distance of the inlet opening 33321 is greater than or equal to 0.5 mm and / or the lowest height distance of the second waterproofing space 3332 is greater than or equal to 0.5 mm. A distance greater than or equal to 0.5 mm allows the waterproofing material to be better filled into the second waterproofing space 3332 under the compression of the overall size of the battery pack by vacuum deposition, preventing the central region of the second waterproofing space 3332 from being filled in place and the waterproofing material from being unevenly distributed in the second waterproofing space 3332.

[0064] In one embodiment, the waterproofing material of the first waterproofing space 3331 and the second waterproofing space 3332 is encapsulated in a single molded part by low-pressure injection molding, wherein the height distance of the inlet opening 33321 is greater than or equal to 0.8 mm and / or the lowest height distance of the second waterproofing space 3332 is greater than or equal to 0.8 mm. A distance greater than or equal to 0.8 mm allows the waterproofing material to be better filled into the second waterproofing space 3332 by low-pressure injection molding under the compression of the overall size of the battery pack, preventing the central region of the second waterproofing space 3332 from being filled in place and the waterproofing material from being unevenly distributed in the second waterproofing space 3332.

[0065] In one embodiment, the waterproofing material of the first waterproofing space 3331 and the second waterproofing space 3332 is encapsulated in a single molded part by the glue filling, wherein the height distance of the inlet opening 33321 is greater than or equal to 0.5 mm and / or the lowest height distance of the second waterproofing space 3332 is greater than or equal to 0.5 mm. By setting a distance greater than or equal to 0.5 mm, the waterproofing material can be better filled into the second waterproofing space 3332 under the compression of the overall size of the battery pack by glue filling, while preventing the central region of the second waterproofing space 3332 from being filled in place and the waterproofing material from being unevenly distributed in the second waterproofing space 3332.

[0066] The control device 4 is provided on the cell holder 22, the control device 4 having a control board 41 and a connector 42, the control board 41 having at least a control module and a communication module, the control board 41 connecting the unit cell 21 from the exposed hole 222 through the connector 42 to achieve at least the communication and control functions, the control module serving to regulate parameters such as the voltage, the current and the temperature in the battery pack to ensure the safe and efficient operation of the entire system, the communication module serving to exchange data with an external device to realize the monitoring of the operating state of the battery pack.

[0067] With reference to Fig. 14 - Fig. 16, the connecting member 42 includes unit cell detection elements 421 and connecting pole pieces 422, the unit cell detection element 421 having a first connection end 4211 and a second connection end 4212, the connecting pole piece 422 being connected to the first connection end 4211, the connecting pole piece 422 being connected to the unit cell 21 through the exposed hole 222, and the second connection end 4212 being connected to the control board 41 by welding to avoid problems that the terminals have poor waterproof performance due to messy wiring through the terminal connection and control board and are inconvenient to maintain inside the battery pack.Compared with the loose "discrete wiring harness + plug-in terminal" structure of conventional power tool battery packs, which brings with it the problem of redundant detection paths and design flaws of the plug-in terminals of the power tool battery pack regarding waterproof performance, this application replaces the discrete wiring harness by adopting a plate / sheet-shaped detection element for unit cells and integrates the detection paths of N-cells into a single connector through the integrated layout of multiple pole pieces, thus realizing the advantages of power tool battery packs in terms of space utilization, dynamic reliability, signal accuracy, and environmental resistance. The reliability, signal accuracy, and environmental tolerance of the power tool battery pack are comprehensively improved, and it is particularly suitable for the high-vibration and high-humidity working conditions of industrial power tools.

[0068] In one embodiment, the second connection end 4212 has a first weld plate 42121 that is at least equal to the number of unit cells 21, wherein the control board 41 has a second weld plate 411 that is at least equal to the number of first weld plates 42121 at the second connection end 4212, wherein the area of ​​the first weld plate 42121 is less than or equal to the area of ​​the second weld plate 411. With the construction that the area of ​​the first weld plate 42121 is less than or equal to the area of ​​the second weld plate 411, a smaller area of ​​the first weld plate 42121 allows it to fully adhere to the larger second weld plate 411, reducing the risk of possible short circuits between adjacent weld plates, thereby improving the safety and reliability of the circuit and ensuring good thermal conduction and electrical connection.At the same time, the smaller weld plate acts on the larger weld plate during thermal expansion, reducing the mechanical stress caused by thermal expansion and contraction, thus reducing fatigue and potential cracking at the brazing joints. This configuration increases the mechanical strength of the weld and improves the stability and durability of the joint.

[0069] In one embodiment, the second connection end 4212 has a first weld plate 42121 that is at least equal to the number of unit cells 21, wherein each first weld plate 42121 is directly connected to the second connection end 4212 of the sensing element of unit cells 421 by a soldering process to form a separate electrical channel that can eliminate the common grounding disturbance of the conventional wiring harness, wherein the control board 41 has a second weld plate 411 that is at least equal to the number of first weld plates 42121 at the second connection end 4212, wherein the precise matching of the number of second weld plates 411 of the control board with the first weld plates of the connection element upgrades the loose architecture of the “discrete plug-in terminal + wiring harnesses” to the integrated paradigm of “matrix of weld plates - rigid connection”.This completely solves the problem of electrical failure and mechanical fatigue of the tool battery pack under high vibration and high humidity conditions. The first welding plate 42121 has at least one through-hole 42122 passing through the first welding plate 42121, the ratio between the opening of the through-hole 42122 and the width of the welding plate of the first welding plate 42121 in which the opening is located being less than or equal to 1:2. By setting a ratio between the opening of the through-hole 42122 and the width of the welding plate of the first welding plate 42121 in which the opening is located being less than or equal to 1:2, the penetration ability of the solder metal through the through-hole during the soldering process is increased, and the mechanical strength and the strength of the conductive connection are improved.The through-hole allows for better filling of the solder to form a more robust and better conductive connection.

[0070] In one embodiment, the second connection end 4212 has a first weld plate 42121 that is at least equal to the number of unit cells 21, and the control board 41 has a second weld plate 411 that is at least equal to the number of first weld plates 42121 at the second connection end 4212. In the first weld plate 42121 and / or the second weld plate 411, the minimum distance e between adjacent weld plates is greater than or equal to 0.2 mm and less than or equal to 2 mm. By setting the minimum distance e between adjacent weld plates to be greater than or equal to 0.2 mm and less than or equal to 2 mm, the risk of short circuits due to solder bridges or contamination by conductive particles is effectively reduced, and welding defects caused by prestress in the manufacturing process can also be reduced.During manufacturing and operation, increased spacing provides greater tolerance for errors in soldering and subsequent operations, increases overall circuit safety and reliability, prevents signal crosstalk, improves signal integrity and transmission efficiency, and allows each area of ​​the weld plate to effectively dissipate heat, avoiding excessive concentration of local overheating problems caused by increased weld plate spacing, allowing better heat diffusion and control.

[0071] In one embodiment, the second connection end 4212 has a first weld plate 42121 that is at least equal to the number of unit cells 21, and the control board 41 has a second weld plate 411 that is at least equal to the number of first weld plates 42121 at the second connection end 4212. The distance f between the peripheral component and the adjacent welding area of ​​the first weld plate 42121 and / or the second weld plate 411 is greater than or equal to 1 mm and less than or equal to 25 mm. By setting f to be greater than or equal to 1 mm and less than or equal to 25 mm, the distance between the weld plate and the peripheral components can be increased, which helps reduce mutual interference from electromagnetic interference. This physical isolation can reduce signal coupling on the circuit board, improve signal integrity, and ensure more stable electrical performance.At the same time, the increased distance between the components and the welding plate reduces the risk of short circuits due to accidental contact or material bridging (e.g., solder overflow), resulting in a greater safety margin for production and subsequent operation of the device. The increased distance also improves the heat diffusion capabilities of the circuit board, allowing heat to be more effectively dissipated from the high-temperature zone, preventing local overheating and heat buildup problems.

[0072] In one embodiment, the first welding plate 42121 and / or the second welding plate 411 has a tinning thickness of 0.05-0.15 mm. Setting the tinning thickness to 0.05-0.15 mm serves to improve the galvanic isolation effect of the soldering area by reducing excessive solder flow during the soldering process and reducing the risk of solder bridges and short circuits.

[0073] In one embodiment, the unit cell detection element is connected to the cell holder, wherein the connection method includes, but is not limited to, connecting it to the cell holder by an adhesive and snap connection.

[0074] An embodiment of the present application is described in more detail below in conjunction with the accompanying drawings: A tool battery pack comprises a housing assembly 1, a cell assembly 2, a pole piece holder 3, and a control device 4, wherein the housing assembly 1 is used to accommodate the cell assembly 2, the pole piece holder 3, and the control device 4; wherein the control device 4 is connected to the pole piece holder 3 and the cell assembly 2.

[0075] The housing assembly 1 has a holder seat (not shown), an opening 13 used to receive the cell assembly, the pole piece holder, and the control device; the opening 13 is arranged corresponding to the location of the pole piece holder 3 in the housing assembly 1 so that the tool pole piece penetrates it and connects to the pole piece holder 3; the holder seat (not shown) is provided on at least one side within the housing assembly 1 to secure the electrical cell assembly 2.

[0076] The cell assembly 2 comprises at least one cylindrical unit cell 21, a cell holder 22, wherein the cell holder 22 is securely attached to the holder seat within the housing assembly 1 by means of a welded or screwed connection, but not limited thereto, to provide additional structural support and protection against vibrations;wherein the cell holder 22 has a receiving slot 221 that receives the unit cell 21, the first end 2211 of the receiving slot 221 having a groove into which the unit cell 21 projects, the second end 2212 of the receiving slot 221 having an exposed hole 222 extending through the cell holder 22, the area within the exposed hole 222 being smaller than the cross-sectional area of ​​the receiving slot 221 that is parallel to the exposed hole 222, the area of ​​the exposed hole 222 being smaller than the maximum area of ​​the first cell end surface 211 that extends into the receiving slot 221;

[0077] The pole piece holder 3 has a terminal assembly 32 and a terminal fixing seat 33, the terminal assembly 32 being fitted into the terminal fixing seat 33, the terminal fixing seat 33 defining the terminal assembly 32, the terminal fixing seat 33 being fixedly connected to the control board, the terminal assembly 32 being connected to the control device 4, the terminal fixing seat 33 having an insertion slot 331, the insertion slot 331 serving to guide the correct insertion direction of the tool pole piece to avoid installation errors resulting in a short circuit, and at the same time can stabilize the tool pole piece to ensure that it is effectively connected to the control device 4.

[0078] The control device 4 is provided on the cell holder 22, the control device 4 having a control board 41 and a connector 42, the control board having at least a control module and a communication module, the control board 41 connecting the unit cell 21 from the exposed hole 222 through the connector 42 to achieve at least the communication and control functions, the control module serving to regulate parameters such as the voltage, the current and the temperature in the battery pack to ensure the safe and efficient operation of the entire system, the communication module serving to exchange data with an external device to realize the monitoring of the operating state of the battery pack.

[0079] The control device 4 is provided on the cell holder 22, the control device 4 having a control board 41 and a connector 42, the control board 41 having at least a control module and a communication module, the control board 41 connecting the unit cell 21 from the exposed hole 222 through the connector 42 to achieve at least the communication and control functions, the control module serving to regulate parameters such as the voltage, the current and the temperature in the battery pack to ensure the safe and efficient operation of the entire system, the communication module serving to exchange data with an external device to realize the monitoring of the operating state of the battery pack.

[0080] With reference to Fig. 14 - Fig.16, the connecting member 42 includes unit cell detection elements 421 and connecting pole pieces 422, the unit cell detection element 421 having a first connection end 4211 and a second connection end 4212, the connecting pole piece 422 being connected to the first connection end 4211, the connecting pole piece 422 being connected to the unit cell 21 through the exposed hole 222, and the second connection end 4212 being connected to the control board 41 by welding to avoid problems that the terminals have poor waterproof performance due to messy wiring through the terminal connection and control board and are inconvenient to maintain inside the battery pack.Compared with the loose "discrete wiring harness + plug-in terminal" structure of conventional power tool battery packs, which brings with it the problem of redundant detection paths and design flaws of the plug-in terminals of the power tool battery pack regarding waterproof performance, this application replaces the discrete wiring harness by adopting the plate / sheet-shaped detection element for 421 unit cells and integrates the detection paths of N-cells into a single connector through the integrated layout of multiple pole pieces, thus realizing the advantages of power tool battery packs in terms of space utilization, dynamic reliability, signal accuracy, and environmental resistance. The reliability, signal accuracy, and environmental tolerance of the power tool battery pack are comprehensively improved, and it is particularly suitable for the high-vibration and high-humidity working conditions of industrial power tools.

[0081] In one embodiment, the second connection end 4212 has a first weld plate 42121 that is at least equal to the number of unit cells 21, wherein each first weld plate 42121 is directly connected to the second connection end 4212 of the unit cell sensing element by a soldering process to form a separate electrical channel that can eliminate the common grounding interference of the conventional wiring harness, wherein the control board 41 has a second weld plate 411 that is at least equal to the number of the first weld plate 42121 at the second connection end 4212, wherein the precise matching of the number of the second weld plates 411 of the control board with the first weld plates 42121 of the connection element upgrades the loose architecture of the “discrete plug-in terminal + wiring harnesses” to the integrated paradigm of “matrix of weld plates - rigid connection”.This completely solves the problem of electrical failure and mechanical fatigue of the tool battery pack under high vibration and high humidity conditions, with the area of ​​the first weld plate 42121 being less than or equal to the area of ​​the second weld plate 411. By specifying that the area of ​​the first weld plate 42121 is less than or equal to the area of ​​the second weld plate 411, a smaller area of ​​the first weld plate 42121 allows it to fully adhere to the larger second weld plate 411, reducing the risk of potential short circuits between adjacent weld plates, improving the safety and reliability of the circuit, and ensuring good thermal conduction and electrical connection.At the same time, the smaller weld plate acts on the larger weld plate during thermal expansion, reducing the mechanical stress caused by thermal expansion and contraction, thus reducing fatigue and potential cracking at the brazing joints. This configuration increases the mechanical strength of the weld and improves the stability and durability of the joint.

[0082] In one embodiment, the second connection end 4212 has a first weld plate 42121 that is at least equal to the number of unit cells 21, wherein the control board 41 has a second weld plate 411 that is at least equal to the number of first weld plates 42121 at the second connection end 4212, wherein the first weld plate 42121 has at least one through hole 42122 that passes through the first weld plate 42121, wherein the ratio between the opening of the through hole 42122 and the width of the weld plate of the first weld plate 42121 in which the opening is located is less than or equal to 1:2.By setting a ratio of less than or equal to 1:2 between the opening of the through-hole 42122 and the width of the weld plate of the first weld plate 42121, in which the opening is located, the solder penetration ability through the through-hole during the soldering process is increased, improving the mechanical strength and the strength of the conductive connection. The through-hole allows for better solder filling to form a more robust and better conductive connection.

[0083] In one embodiment, the second connection end 4212 has a first weld plate 42121 that is at least equal to the number of unit cells 21, and the control board 41 has a second weld plate 411 that is at least equal to the number of first weld plates 42121 at the second connection end 4212. In the first weld plate 42121 and / or the second weld plate 411, the minimum distance e between adjacent weld plates is greater than or equal to 0.2 mm and less than or equal to 2 mm. By setting the minimum distance e between adjacent weld plates to be greater than or equal to 0.2 mm and less than or equal to 2 mm, the risk of short circuits due to solder bridges or contamination by conductive particles is effectively reduced, and welding defects caused by prestress in the manufacturing process can also be reduced.During manufacturing and operation, increased spacing provides greater tolerance for errors in soldering and subsequent operations, increases overall circuit safety and reliability, prevents signal crosstalk, improves signal integrity and transmission efficiency, and allows each area of ​​the weld plate to effectively dissipate heat, avoiding excessive concentration of local overheating problems caused by increased weld plate spacing, allowing better heat diffusion and control.

[0084] In one embodiment, the second connection end 4212 has a first weld plate 42121 that is at least equal to the number of unit cells 21, and the control board 41 has a second weld plate 411 that is at least equal to the number of first weld plates 42121 at the second connection end 4212. The distance f between the peripheral component and the adjacent welding area of ​​the first weld plate 42121 and / or the second weld plate 411 is greater than or equal to 1 mm and less than or equal to 25 mm. By setting f to be greater than or equal to 1 mm and less than or equal to 25 mm, the distance between the weld plate and the peripheral components can be increased, which helps reduce mutual interference from electromagnetic interference. This physical isolation can reduce signal coupling on the circuit board, improve signal integrity, and ensure more stable electrical performance.At the same time, the increased distance between the components and the welding plate reduces the risk of short circuits due to accidental contact or material bridging (e.g., solder overflow), resulting in a greater safety margin for production and subsequent operation of the device. The increased distance also improves the heat diffusion capabilities of the circuit board, allowing heat to be more effectively dissipated from the high-temperature zone, preventing local overheating and heat buildup problems.

[0085] In one embodiment, the first welding plate 42121 and / or the second welding plate 411 has a tinning thickness of 0.05-0.15 mm. Setting the tinning thickness to 0.05-0.15 mm serves to improve the galvanic isolation effect of the soldering area by reducing excessive solder flow during the soldering process and reducing the risk of solder bridges and short circuits.

[0086] In one embodiment, the first welding plate 42121 and / or the second welding plate 411 has a tinning thickness of 0.05-0.1 mm.

[0087] In one embodiment, the unit cell detection element is connected to the cell holder, wherein the connection method includes, but is not limited to, connecting it to the cell holder by an adhesive and snap connection.

[0088] It will be understood by those skilled in the art that the embodiments described above are merely exemplary and that numerous modifications in form and design may be made without departing from the spirit or scope of the present application.

Claims

[1] A tool battery pack comprising a housing assembly, a cell assembly, a pole piece holder, and a control device, wherein the housing assembly serves to accommodate the cell assembly, the pole piece holder, and the control device; wherein the control device is connected to the pole piece holder and the cell assembly; wherein the cell assembly comprises a plurality of unit cells and a cell holder, wherein the control device is provided on the cell holder; wherein the control device has a control board and a connecting element, characterized byin that the connecting element has detection elements of a sheet-like shape for unit cells and connecting pole pieces, wherein one end of the connecting pole piece is connected to the unit cell accordingly, wherein the detection element for unit cells has a first connection end and a second connection end, wherein the other end of the connecting pole piece is directly connected to the first connection end, wherein the first connection end integrates a plurality of connection pieces, wherein the second connection end is connected to the control board by a welding process. [2] Tool battery pack according to claim 1, characterized by that the second connection end has a first weld plate which corresponds at least to the number of unit cells. [3] Tool battery pack according to claim 2, characterized by that the control board has a second welding plate that is at least equal to the number of the first welding plate at the second connection end. [4] Tool battery pack according to claim 3, characterized by that the area of ​​the first welding plate is less than or equal to the area of ​​the second welding plate. [5] Tool battery pack according to claim 2, characterized by that the first welding plate has at least one through hole passing through the first welding plate. [6] Tool battery pack according to claim 5, characterized by that the ratio between the opening of the through hole and the width of the welding plate of the first welding plate in which the opening is located is less than or equal to 1:

2. [7] Tool battery pack according to claim 3, characterized by that the minimum distance e between adjacent welding plates is greater than or equal to 0.2 mm and less than or equal to 2 mm. [8] Tool battery pack according to claim 3, characterized bythat the distance f between the peripheral component and the adjacent first welding plate is greater than or equal to 1 mm and less than or equal to 25 mm. [9] Tool battery pack according to claim 3, characterized by that the distance f between the peripheral component and the adjacent second welding plate is greater than or equal to 1 mm and less than or equal to 25 mm. [10] Tool battery pack according to claim 2, characterized by that the first welding plate has a tinning thickness of 0.05-0.15 mm. [11] Tool battery pack according to claim 3, characterized by that the second welding plate has a tinning thickness of 0.05-0.15 mm.

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