Battery packs, power tools and power supply units

Abstract

This application discloses a battery pack, a power tool, and a power supply device. The battery pack includes: a housing; a plurality of battery cells disposed within the housing; and an insulating layer applied to at least some of the polar end faces of the battery cells, wherein the insulating layer is made of a second material having water-swellable properties.

Description

Technical Field

[0001] This application relates to the field of power tool technology, specifically to a battery pack, power tool, and power supply device. Background Technology

[0002] A type of battery pack in related technologies can power power tools, household appliances, or other electric devices. Battery pack safety has always been a major concern. In particular, thermal runaway in battery packs poses a significant threat to battery safety and the personal and property safety of users. To avoid or reduce thermal runaway in battery packs, safety structures or materials are typically incorporated to mitigate its impact.

[0003] This section provides background information related to this application, which is not necessarily prior art. Utility Model Content

[0004] One object of this application is to solve or at least alleviate some or all of the aforementioned problems. Therefore, one object of this application is to provide a battery pack, power tools, and a power supply device.

[0005] To achieve the above objectives, this application adopts the following technical solution:

[0006] A battery pack includes: a housing; a plurality of battery cells disposed within the housing; wherein the battery pack further includes an insulating layer, the insulating layer being applied at least to the polar end faces of some of the battery cells, and the insulating layer being made of a second material having water-swellable properties.

[0007] In some embodiments, the battery pack further includes a cell connector, and an insulating layer at least covers the electrical connection between the cell connector and the polarity end face.

[0008] In some embodiments, the battery pack further includes: a cell support for supporting the cell unit; an end cap disposed on the polarity end face; and an insulating layer applied between the cell support and the end cap.

[0009] In some embodiments, the second material comprises water-swellable polyurethane.

[0010] In some embodiments, the water absorption expansion coefficient of the second material is greater than or equal to 150% and less than or equal to 500%.

[0011] In some embodiments, the housing is substantially sealed by a second material.

[0012] In some embodiments, the second material remains insulating both before and after swelling upon contact with water.

[0013] In some embodiments, at least a portion of the battery cell is surrounded by a first material in a water-locking state.

[0014] A battery pack includes: a housing; a plurality of battery cells disposed within the housing; a power transmission terminal configured to at least transmit power; and a circuit board assembly including at least circuit boards associated with the battery cells and / or circuit boards associated with the power transmission terminal; wherein the battery pack further includes an insulating layer, the insulating layer being applied at least to the circuit board assembly, and the insulating layer being composed of a second material having water-swellable properties.

[0015] An electric tool includes: a tool housing; a motor and an electrical connection assembly disposed within the tool housing; a battery pack configured to power at least the motor; wherein the electric tool further includes an insulating layer applied at least to the electrical connection assembly, and the insulating layer is made of a second material having water-swellable properties.

[0016] A power supply device includes: a device housing; an electrical power transmission end configured to at least transmit electrical power; an electrical power processing module configured to process the transmitted electrical power; and an electrical connection assembly disposed within the device housing; wherein the power supply device further includes an insulating layer, the insulating layer being applied at least to the electrical connection assembly, and the insulating layer being composed of a second material having water-absorbing and swelling properties.

[0017] A battery pack includes: a housing; a plurality of battery cells disposed within the housing; wherein at least a portion of the battery cells are surrounded by a first material in a water-locking state.

[0018] In some embodiments, the housing is a fully sealed housing.

[0019] In some embodiments, the internal air pressure of the battery pack is less than one standard atmosphere.

[0020] In some embodiments, at least a portion of the battery cell is surrounded by a heat dissipation medium.

[0021] In some embodiments, the heat dissipation medium includes a first material in a water-locking state.

[0022] In some embodiments, the first material includes at least one of a water-absorbing resin and a water-absorbing fiber.

[0023] In some embodiments, at least a portion of the cell's polar end face is provided with an insulating layer, and the insulating layer is made of a second material that has water-absorbing and swelling properties.

[0024] In some embodiments, the water absorption expansion coefficient of the second material is greater than that of the first material.

[0025] In some embodiments, the second material comprises water-swellable polyurethane.

[0026] A battery pack includes: a housing; a plurality of battery cells disposed within the housing; and a battery cell separator disposed within the housing, the battery cell separator being configured to contact and space from or surround at least a portion of the battery cells; wherein the battery cell separator is at least partially composed of a first material in a water-locking state, or the first material in a water-locking state is disposed within the battery cell separator.

[0027] In some embodiments, the cell separator has a plurality of receiving holes, and a first material in a water-locking state is disposed in the receiving holes.

[0028] In some embodiments, the cell separator is a cell support.

[0029] In some embodiments, the first material includes at least one of a water-absorbing resin and a water-absorbing fiber.

[0030] In some embodiments, the battery pack further includes a pressure relief device that reduces the internal pressure of the battery pack after the internal pressure reaches an upper limit.

[0031] A battery pack includes: a housing; a plurality of battery cells disposed within the housing; wherein at least some of the battery cells are surrounded by a first material in a water-locking state; the housing is provided with a pipe interface for connection to an external circulating cooling system; the first material is configured to be extracted from the battery pack for circulating cooling when the pipe interface is connected to the circulating cooling system.

[0032] In some embodiments, the pipe interface is sealed when the circulating cooling system is not connected.

[0033] In some embodiments, the housing is a fully sealed housing.

[0034] In some embodiments, the pipe interface includes a pipe inlet and a pipe outlet, and a one-way valve is provided at the pipe inlet and the pipe interface.

[0035] In some embodiments, the circulating cooling system is configured to be powered by a battery pack.

[0036] In some embodiments, the circulating cooling system is configured to be powered by an external power source.

[0037] In some embodiments, the battery pack further includes a retainer disposed within the housing, which retains the first material in a circulating flow path adjacent to the cell unit during the process of the circulating heat dissipation system driving the first material to circulate heat dissipation.

[0038] In some embodiments, the battery pack further includes a cell support that supports the cell unit; the retainer includes the cell support.

[0039] In some embodiments, the first material includes a water-absorbing resin.

[0040] In some embodiments, the first material is in a fluid state within the battery pack.

[0041] A charger includes: a charger housing; a circulating heat dissipation system disposed inside the charger housing; a heat dissipation system interface is provided on the charger housing; when the charger is electrically connected to a battery pack, the heat dissipation system interface is connected to the battery pack to draw out the cooling fluid inside the battery pack for circulating heat dissipation.

[0042] In some embodiments, the circulating cooling system includes at least a pump and connecting pipes; the pump includes a plunger pump or a peristaltic pump.

[0043] In some embodiments, the circulating cooling system further includes a cooling device, one end of which is connected to the pump and the other end of which is connected to the cooling system interface.

[0044] In some embodiments, the heat dissipation device includes a fan and / or a condenser.

[0045] In some embodiments, the pump's output power is greater than or equal to 0.1W and less than or equal to 200W.

[0046] In some embodiments, the maximum charging rate of the charger is greater than or equal to 2C.

[0047] In some embodiments, the charger is adapted to a battery pack for power tools.

[0048] In some embodiments, the charger housing is also provided with a charger interface, which is electrically connected to the battery pack to charge the battery pack.

[0049] In some embodiments, the cooling fluid includes a water-absorbing resin, cooling oil, liquid water, or fluorinated liquid.

[0050] A charging system includes: a battery pack, comprising: a housing; a plurality of battery cells disposed within the housing; a cooling fluid disposed within the housing; and a pipe interface disposed on the housing; and a charger, comprising: a charger housing; and a circulating cooling system disposed within the charger housing; and a cooling system interface disposed on the charger housing; wherein, when the battery pack and the charger are coupled, the pipe interface is connected to the cooling system interface, and the cooling fluid is drawn from the battery pack by the circulating cooling system for circulating cooling.

[0051] In some embodiments, the circulating cooling system includes at least a pump and connecting pipes; the pump includes a plunger pump or a peristaltic pump.

[0052] In some embodiments, the circulating cooling system further includes a cooling device; one end of the cooling device is connected to the pump, and the other end is connected to the cooling system interface.

[0053] In some embodiments, the heat dissipation device includes a fan and / or a heat sink.

[0054] In some embodiments, the pump's output power is greater than or equal to 0.1W and less than or equal to 200W.

[0055] In some embodiments, the cooling fluid includes cooling gas and / or coolant.

[0056] In some embodiments, the coolant includes at least one of water, water-absorbing resin, perfluorohexanone, and cooling oil.

[0057] In some embodiments, the maximum charging rate of the charger is greater than or equal to 2C.

[0058] In some embodiments, the charging system is adapted to the power tool, the battery pack powers the power tool, and the charger is adapted to the battery pack for the power tool.

[0059] In some embodiments, the battery pack further includes a retainer disposed within the housing, which retains the cooling fluid in the circulation path adjacent to the battery cell during the circulation cooling system driving the cooling fluid to circulate and dissipate heat.

[0060] An electric tool system includes: a battery pack, comprising: a housing; multiple battery cells disposed within the housing; a cooling fluid disposed within the housing; and a pipe interface provided on the housing; and an electric tool, comprising: a tool body; and a circulating cooling system disposed within the tool body; with a cooling system interface formed on the tool body; wherein, when the battery pack and the tool body are coupled, the pipe interface is connected to the cooling system interface, and the cooling fluid is drawn from the battery pack by the circulating cooling system for circulating cooling.

[0061] An electric tool includes: a tool body; a circulating cooling system disposed within the tool body; a cooling system interface formed on the tool body; when the electric tool is connected to a battery pack, the cooling system interface is connected to the battery pack to draw cooling fluid from the battery pack for circulating cooling.

[0062] An adapter includes: an adapter housing; a circulating cooling system disposed within the adapter housing; a cooling system interface provided on the adapter housing; when the adapter is electrically connected to a battery pack, the cooling system interface is connected to the battery pack to draw cooling fluid from the battery pack for circulating cooling.

[0063] The advantages of this application are that it provides a battery pack, power tool, and power supply device with good safety performance and easy manufacturing process, which also has the characteristics of being green and environmentally friendly; and provides a battery pack, charger, charging system, and power tool system with even better safety performance, which has good heat dissipation performance and can effectively control heat spread. Attached Figure Description

[0064] Figure 1 This is a schematic diagram of the battery pack and power tool used as embodiments in this application;

[0065] Figure 2 This is a perspective view of a battery pack as one embodiment of this application;

[0066] Figure 3 yes Figure 2 A 3D view of multiple battery cell units, cell separators, and circuit board assemblies within the battery pack shown.

[0067] Figure 4 yes Figure 2 The exploded view shows the cell separator, polarity face, and circuit board assembly inside the battery pack.

[0068] Figure 5 yes Figure 2 The image shows a cross-sectional view of the battery pack from one perspective.

[0069] Figure 6 yes Figure 2 The battery pack shown is a cross-sectional view from another perspective;

[0070] Figure 7 This is a perspective view of a power supply device as an embodiment of this application;

[0071] Figure 8 This is a schematic diagram of the battery pack and external circulating heat dissipation system as one embodiment of this application;

[0072] Figure 9 This is a perspective view of a charging system as one embodiment of this application;

[0073] Figure 10A yes Figure 9 A 3D view of the battery pack and charger in the uncoupled state in the charging system shown.

[0074] Figure 10B yes Figure 9 Another perspective view of the charging system shown, with the battery pack and charger in an uncoupled state;

[0075] Figure 11 yes Figure 8 A three-dimensional view of part of the internal structure of the battery pack and charger in the charging system shown.

[0076] Figure 12 This is a schematic diagram of a circulating heat dissipation system as one embodiment of this application;

[0077] Figure 13 This is a schematic diagram of the connection point between the pipe interface of the battery pack and the heat dissipation system interface of the circulating heat dissipation system in this application;

[0078] Figure 14This is a perspective view of an electric tool system as an embodiment of this application.

[0079] Caption:

[0080] 100. Battery pack; 10. Housing; 11. Pipe interface; 111. One-way valve; 12. Charging interface; 20. Cell unit; 30. Cell separator; 31. Cell bracket; 32. Cell assembly separator; 33. End cap; 40. Electrical connection assembly; 41. Cell connecting piece; 42. Polar end face; 50. Circuit board assembly; 51. Circuit board; 60. First material / cooling fluid; 70. Second material; 80. Retaining element;

[0081] 200. Power tools / tool ​​bodies; 200a. Ride-on lawnmowers; 200b. Electric drills; 200c. Chainsaws; 200d. Lawn trimmers; 200e. Hair dryers; 200f. All-terrain vehicles; 220. Circulating cooling systems; 300. Power supply units; 400. Chargers; 410. Charger housings; 411. Cooling system interfaces; 412. Charger interfaces; 420. Circulating cooling systems; 421. Pumps; 422. Connecting pipes; 423. Cooling devices; 423a. Fans; 423b. Condensers; 500. Charging systems; 600. Power tool systems. Detailed Implementation

[0082] Before explaining any implementation of this application in detail, it should be understood that this application is not limited to its application to the structural details and component arrangements set forth in the following description or shown in the above drawings.

[0083] In this application, the terms "comprising," "including," "having," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element.

[0084] In this application, the term "and / or" describes the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent three cases: A existing alone, A and B existing simultaneously, and B existing alone. Additionally, the character " / " in this application generally indicates that the preceding and following related objects have an "and / or" relationship.

[0085] In this application, the terms "connection," "combination," "coupling," and "installation" can refer to direct connection, combination, coupling, or installation, or indirect connection, combination, coupling, or installation. For example, a direct connection refers to two parts or components being connected together without the need for an intermediary, while an indirect connection refers to two parts or components each being connected to at least one intermediary, with the connection achieved through the intermediary. Furthermore, "connection" and "coupling" are not limited to physical or mechanical connections or couplings, but can also include electrical connections or couplings.

[0086] In this application, those skilled in the art will understand that relative terms (e.g., “about,” “approximately,” “basically,” etc.) used in conjunction with quantities or conditions are to include the values ​​and have the meaning indicated by the context. For example, such relative terms include at least the degree of error associated with the measurement of a particular value, tolerances associated with the particular value due to manufacturing, assembly, use, etc. Such terms should also be considered as disclosing a range defined by the absolute values ​​of the two endpoints. Relative terms may refer to a certain percentage (e.g., 1%, 5%, 10% or more) of the indicated value. Numerical values ​​not using relative terms should also be disclosed as specific values ​​with tolerances. Furthermore, “basically” when expressing relative angular relationships (e.g., substantially parallel, substantially perpendicular) may refer to a certain degree (e.g., 1 degree, 5 degrees, 10 degrees or more) added to or subtracted from the indicated angle.

[0087] In this application, those skilled in the art will understand that the function performed by a component can be performed by one component, multiple components, one part, or multiple parts. Similarly, the function performed by a part can also be performed by one part, one component, or a combination of multiple parts.

[0088] In this application, the directional terms "upper," "lower," "left," "right," "front," and "rear" are used to describe the orientation and positional relationships shown in the accompanying drawings and should not be construed as limiting the embodiments of this application. Furthermore, in the context, it should be understood that when an element is mentioned as being connected "upper" or "lower" to another element, it can be directly connected to the other element "upper" or "lower," or indirectly connected through an intermediate element. It should also be understood that directional terms such as upper side, lower side, left side, right side, front side, and rear side not only represent positive orientation but can also be understood as lateral orientation. For example, "below" can include directly below, lower left, lower right, lower front, and lower rear.

[0089] In this application, the terms "controller," "processor," "central processing unit," "CPU," and "MCU" are used interchangeably. When using the unit "controller," "processor," "central processing unit," "CPU," or "MCU" to perform a specific function, unless otherwise stated, these functions may be performed by a single or multiple of the aforementioned units.

[0090] In this application, the terms "device," "module," or "unit" are used to describe devices that can be implemented in hardware or software to perform a specific function.

[0091] In this application, the terms “calculation,” “judgment,” “control,” “determine,” “identify,” etc., refer to the operation and process of a computer system or similar electronic computing device (e.g., controller, processor, etc.).

[0092] The technical solution proposed in this application will be described in detail below with reference to the accompanying drawings and specific embodiments.

[0093] This application primarily provides a battery pack 100 with improved safety performance, as well as a power supply device 300 and a power tool 200 with improved safety performance. Any two of the battery pack 100, power supply device 300, and power tool 200 in this application can have a charge-discharge relationship, thereby constituting a power system or tool system with higher safety. The battery pack 100 can power different types of power tools 200, see reference [reference missing]. Figure 1The power tools 200 that can be powered by the battery pack 100 in this application include, but are not limited to: a ride-on lawnmower 200a, an electric drill 200b, a chainsaw 200c, a lawn mower 200d, a hair dryer 200e, and an all-terrain vehicle 200f. In addition to the illustrations, the power tools 200 that can be powered by the battery pack 100 can also be handheld power tools, such as drills, pruning machines, and circular saws. Alternatively, the power tools 200 can also be benchtop tools, such as table saws, miter saws, metal cutters, and electric wood milling machines. Alternatively, the power tools 200 can also be push-type power tools, such as push lawnmowers and push snow sweepers. Alternatively, the power tools 200 can also be ride-on power tools, such as ride-on lawnmowers, stand-up lawnmowers, and all-terrain vehicles. Alternatively, the power tools 200 can also be outdoor wheeled tools or outdoor electric vehicles. Alternatively, the power tool 200 can also be a robotic tool, such as a lawnmower robot, snowplow robot, etc. In some embodiments, the power tool 200 can be a light bulb, electric fan, electric vehicle, etc. In some embodiments, the power tool 200 can also be a gardening tool, such as a pruning machine, hair dryer, lawnmower, chainsaw, etc. Alternatively, the power tool 200 can also be a decorating tool, such as a screwdriver, nail gun, circular saw, sander, etc. In some embodiments, the power tool 200 can also be a vegetation care tool, such as a lawn mower, lawn trimmer, pruning machine, chainsaw, etc. Alternatively, the power tool 200 can also be a cleaning tool, such as a hair dryer, snowplow, washing machine, etc. In some embodiments, the power tool 200 can also be a drilling tool, such as a drill, screwdriver, wrench, hammer drill, etc. Alternatively, the power tool 200 can also be a sawing tool, such as a reciprocating saw, jigsaw, circular saw, etc. Alternatively, the power tool 200 can also be a grinding tool, such as an angle grinder, sander, etc. Alternatively, the power tool 200 can also be other tools, such as a light bulb, fan, etc. It is understood that other electrical devices that can be powered by the battery pack 100 may also be included in the scope of the power tool 200 described in this application.

[0094] In some embodiments, the battery pack, charger, power supply, and charging system described below can be adapted in a platform-like manner to be used with first-type and second-type power tools. The first-type power tools include handheld power tools such as jigsaws, impact wrenches, pruning shears, and chainsaws, while the second-type power tools include outdoor work vehicles such as ride-on lawnmowers, stand-up lawnmowers, and all-terrain vehicles. The battery pack, charger, power supply, and charging system described below are compatible with the aforementioned first-type and second-type power tools in terms of mechanical structure and electrical characteristics. Furthermore, the battery pack, charger, power supply, and charging system can also be adapted to third-type power tools, which can be table saws, miter saws, metal cutters, and other table-type tools.

[0095] It should be noted that power tools 200 generally have a battery pack mounting section for inserting the battery pack 100. The structure and location of the battery pack mounting section vary depending on the tool. Outdoor wheeled tools, outdoor electric vehicles, or ride-on lawnmowers generally have a set of wheels, a motor, working attachments (such as a mowing assembly), and a drive motor, etc. The conventional components of other types of power tools 200 will not be described in detail here.

[0096] refer to Figures 2 to 6 The battery pack 100 includes at least a housing 10 and one or more battery cell units 20. The housing 10 forms the main external structure of the battery pack 100, and its interior has a space for accommodating one or more battery cell units 20, which are used to store electrical energy. In addition to the housing 10 and the one or more battery cell units 20, the battery pack 100 generally also includes an electrical connection assembly 40 and a circuit board assembly 50, which work together to realize the power transmission and control of the battery pack 100 at the hardware and software levels.

[0097] The battery cell unit 20 can be a cylindrical battery, a prismatic battery, a pouch battery, an aluminum-plastic film battery, or a metal-cased battery, etc. In some embodiments, the battery cell unit 20 can be a unitab battery, a bitab battery, or a plenum battery. In some embodiments, at least some of the battery cell units 20 can be lithium iron phosphate cells, or at least some of the battery cell units 20 can be lithium-ion cells, such as ternary lithium cells, or at least some of the battery cell units 20 can be sodium-ion cells, or at least some of the battery cell units 20 can be capacitor batteries, or at least some of the battery cell units 20 can be supercapacitors. In some embodiments, the battery pack 100 contains a mixture of battery cell units 20 made of various materials or with different properties. The number of battery cell units 20 in the battery pack 100 can be set according to actual needs.

[0098] like Figure 4 , Figure 6 As shown, the electrical connection assembly 40 may include a cell connecting piece 41, which can connect the positive and negative terminals of multiple cell units 20, thereby forming a series or parallel connection of multiple cell units 20. The number of cell units 20 connected to the cell connecting piece 41 is specifically related to the rated voltage of the battery pack 100 or the capacity of the battery pack 100. In this embodiment, the cell connecting piece 41 is substantially attached to the positive or negative terminals of multiple cell units 20.

[0099] like Figure 3As shown, the circuit board assembly 50 may include at least one circuit board 51 and electrical connectors connecting the circuit board 51 and the battery cell unit 20. The electrical connection assembly 40 may also include interfaces on the housing 10 for connecting to external electrical devices and / or charging devices, as well as several internal interfaces disposed within the housing 10. The external interfaces may include positive and negative terminals of the battery pack 100 and communication terminals. The positive and negative terminals are used for charging and discharging, and the communication terminals are used for data transmission. The discharging interface and the charging interface may be separate interfaces, or they may share a single charging / discharging interface. It is understood that the division of components included in the electrical connection assembly 40 and the circuit board assembly 50 is not absolute; for example, the electrical connectors connecting the circuit board 51 and the battery cell unit 20 may also be considered part of the electrical connection assembly 40.

[0100] The diameter of the battery cell unit 20 is greater than or equal to 3 cm, for example, the diameter of the battery cell unit 20 is 3 cm, 3.5 cm, or 4 cm, etc. In some embodiments, the diameter of the battery cell unit 20 is greater than or equal to 4 cm, for example, it can be 4.5 cm, 4.6 cm, or 5 cm, etc. In some embodiments, the height of the battery cell unit 20 is greater than or equal to 8 cm, for example, the height of the battery cell unit 20 is 8 cm, 9 cm, 10 cm, 11 cm, 12 cm, 13 cm, or 13.5 cm, etc. The size of the battery cell unit 20 is relatively large, and the battery cell units 20 are not completely sealed together. If some battery cell units 20 experience thermal runaway during the operation of the battery pack 100, it will affect its adjacent battery cell units 20, thereby causing the battery pack 100 to experience a serious safety accident such as explosion or fire.

[0101] To improve the heat dissipation capacity of the battery cell unit 20 and enhance the safety performance of the battery pack 100, such as Figure 5 , Figure 6 As shown, in this application, at least a portion of the battery cell 20 is surrounded by a first material 60 in a water-locking state. The water-locking state of the first material 60 stems from its water-absorbing and moisture-absorbing physical properties; water molecules can be adsorbed in a liquid state on the surface or inside the first material 60. It should be noted that in this application, the battery cell 20 is first surrounded by an insulating material, and then the first material 60 surrounds the insulating material surrounding the battery cell 20. Therefore, the first material 60 in a water-locking state does not cause leakage problems in the battery cell 20. Furthermore, the portion of the first material 60 in the water-locking state still retains its insulating properties, further preventing the aforementioned leakage problem.

[0102] like Figure 5 , Figure 6As shown, in some embodiments, the first material 60 in a water-locking state wraps around the periphery of the cell unit 20 along the axial direction, and the axial direction of the cell unit 20 is perpendicular to the polar end face 42 of the cell unit 20. In some embodiments, the ratio of the axial length of the first material 60 surrounding the periphery of the cell unit 20 to the axial length of the cell unit 20 itself is greater than or equal to 0.3. Optionally, the ratio of the axial length of the first material 60 to the axial length of the cell unit 20 itself is greater than or equal to 0.5. In other embodiments, it is not excluded that other parts of the battery pack 100 housing 10 may also be provided with the first material 60 in a water-locking state.

[0103] Because water has a high specific heat capacity and high thermal conductivity, as the battery cell 20 generates heat during operation, the water contained within the first material 60 surrounding the battery cell 20 can effectively absorb and conduct the heat generated by the battery cell 20, thereby improving the heat dissipation capacity of the battery cell 20. Furthermore, when the heat generated by the battery cell 20 exceeds a certain limit, the water contained within the first material 60 will vaporize, changing from a liquid state to a gaseous state and absorbing a large amount of heat. At this time, the water that was originally locked within the first material 60 will detach from the first material 60 and freely enter the housing 10 of the battery pack 100, and the first material 60 will gradually change from a water-locked state to a non-water-locked state. As the cell unit 20 finishes its operation, the temperature of the battery pack 100 gradually drops. The water within the housing 10 liquefies, transforming from a gaseous to a liquid state and being reabsorbed by the first material 60. The first material 60 gradually returns to its water-locked state. This vaporization-liquefaction of water forms a recyclable heat dissipation system within the battery pack 100, improving the heat dissipation capacity of the cell unit 20, enhancing the safety performance of the battery pack 100, and preventing thermal runaway. In some cases, the first material 60 in its water-locked state also has a certain fire-extinguishing effect. Furthermore, the aforementioned technical improvement achieved by the first material 60 in conjunction with water does not impose any environmental burden, utilizes entirely green materials, and has no pollution or damage issues.

[0104] In some embodiments, the housing 10 of the battery pack 100 is a fully sealed housing, that is, the housing space is basically a sealed space, so that the water originally locked in the first material 60 will not escape from the housing 10 even after absorbing heat and vaporizing, and the above-mentioned cycle process can be realized.

[0105] In some embodiments, the housing 10 of the battery pack 100 is further provided with a pressure relief device to discharge gas from the housing 10 when the gas pressure inside the battery pack 100 is too high, thereby preventing accidents such as explosions. In some embodiments, the housing 10 of the battery pack 100 has one or more weak points achieved by making the housing 10 thinner. The weak points on the housing 10 can be ruptured by gas after the gas pressure inside the pack reaches a critical point, thereby achieving the above-mentioned pressure relief and explosion prevention function.

[0106] In some embodiments, the internal pressure of the battery pack 100 is less than one standard atmosphere, i.e., it is in a negative pressure state. This lowers the boiling point of water within the battery pack 100 and facilitates water evaporation. The first material 60, in a water-locked state, becomes more sensitive to temperature changes in the cell unit 20. In some embodiments, based on experimental testing and analysis, the critical temperature for water vaporization within the first material 60 can be controlled by adjusting the internal pressure of the battery pack 100. In some embodiments, the internal pressure of the battery pack 100 is greater than or equal to 0.3 standard atmospheres. Optionally, the internal pressure of the battery pack 100 is greater than or equal to 0.4 standard atmospheres and less than or equal to 0.8 standard atmospheres. Preferably, the internal pressure of the battery pack 100 is greater than or equal to 0.5 standard atmospheres and less than or equal to 0.7 standard atmospheres. In one embodiment, the internal pressure of the battery pack 100 is 0.6 standard atmospheres. In some embodiments, the pressure relief device described above can also monitor and regulate the air pressure inside the battery pack 100 to keep it within a preset range that allows the first material 60 in a water-locking state to operate precisely. The setting of the air pressure inside the battery pack 100 can be referenced in the following table of water vapor pressure and saturation temperature.

[0107]

[0108] In some embodiments, the first material 60 includes at least one of a water-absorbing resin and a water-absorbing fiber. Alternatively, the first material 60 may be a mixture or polymer of one or more of a superabsorbent polymer, absorbent paper or other absorbent fibers, a swelling agent, zeolite, activated carbon, and rock wool. Specifically, the first material 60 will not degrade at least during the normal lifespan of the battery pack 100, ensuring its continued functionality throughout the battery pack 100's lifespan. In some embodiments, a portion (of the water-locked first material 60) is also fluid.

[0109] In some embodiments, at least a portion of the battery cell units 20 within the battery pack 100 are surrounded by a heat dissipation medium. In some embodiments, the first material 60 in a water-locking state is part of the heat dissipation medium; that is, in addition to the first material 60 in a water-locking state, other heat dissipation media may be provided around at least a portion of the battery cell units 20 within the battery pack 100. Specifically, in one embodiment, liquid water may be filled into the housing 10 of the battery pack 100, and the battery cell units 20 may or may not be surrounded by the first material 60. The liquid water within the housing 10 can still complete the aforementioned heat conduction, vaporization, and liquefaction processes to a certain extent to improve heat dissipation and safety. In another embodiment, high-flash-point oil may be filled into the housing 10 of the battery pack 100, and the battery cell units 20 may be surrounded by a material capable of locking the oil within.

[0110] In some embodiments, the thickness of the heat dissipation medium surrounding the cell unit 20 is less than or equal to 4 mm. In some embodiments, the thickness of the heat dissipation medium surrounding the cell unit 20 is less than or equal to 3 mm. Optionally, the thickness of the heat dissipation medium surrounding the cell unit 20 is less than or equal to 1 mm, or greater than or equal to 1 mm and less than or equal to 2 mm, or greater than or equal to 2 mm and less than or equal to 3 mm. Preferably, the thickness of the heat dissipation medium surrounding the cell unit 20 is greater than or equal to 1 mm and less than or equal to 2 mm.

[0111] In some embodiments, the ratio of the weight of the first material 60 surrounding a battery cell 20 to the weight of water locked within the first material 60 is less than or equal to 1:1. Optionally, the ratio of the weight of the first material 60 surrounding a battery cell 20 to the weight of water locked within the first material 60 is greater than or equal to 1:150 and less than or equal to 1:1. The weight of water locked within the first material 60 surrounding a battery cell 20 is less than or equal to 5g. Optionally, the mass of water locked within the first material 60 surrounding a battery cell 20 is greater than or equal to 1g and less than or equal to 3g. Preferably, the mass of water locked within the first material 60 surrounding a battery cell 20 is between 1g and 2g.

[0112] In one alternative implementation, such as Figure 5 , Figure 6 As shown, within the battery pack 100, the first material 60 in a water-locking state can form at least a portion of the cell separator 30 or be disposed within the cell separator 30. The cell separator 30 can be disposed together with the cell unit 20 within the receiving space formed by the housing 10. The cell separator 30 can contact at least a portion of the cell unit 20 and can be spaced apart from or surround at least a portion of the cell unit 20. Specifically, in some embodiments, the first material 60 in a water-locking state can be used directly to form the cell separator 30 or a portion of the cell separator 30 within the battery pack 100. In other embodiments, other materials can be used to form the cell separator 30, and the interior of the cell separator 30 can be filled with the first material 60 in a water-locking state, or the first material 60 in a water-locking state can be surrounded on the surface of the cell separator 30. When the first material 60 in a water-locking state is disposed within the cell separator 30, at least a portion of its surface is not sealed to allow the water locked within the first material 60 to vaporize.

[0113] In some embodiments, the cell separator 30 made of the first material 60 can have a honeycomb-like, sponge-like, or other porous structure to facilitate the vaporization of water locked within the first material 60. In other embodiments, the cell separator 30 can have multiple receiving holes, and the first material 60 in the water-locked state can be disposed and filled in the receiving holes. The receiving holes on the cell separator 30 can be located near the position of the cell unit 20 where heat generation is higher.

[0114] Similar to the above, in some embodiments, the first material 60 constituting or filling the cell separator 30 in a water-locking state includes at least one of water-absorbing resin and water-absorbing fiber. Specifically, it may include one or more of superabsorbent polymer, water-absorbing paper or other water-absorbing fibers, and will not degrade within the normal lifespan of the battery pack 100.

[0115] like Figures 3 to 6 As shown, in some embodiments, the cell separator 30 includes a cell support 31, and in other embodiments, the cell separator 30 also includes a cell group separator 32, etc. The cell support 31 and / or the cell group separator 32, etc., of the cell separator 30 can independently or in combination support one or more cell units 20, and can separate several cell units 20 from other cell units 20, or separate different cell units 20 from each other, or act as a enclosure for at least some of the cell units 20. In some embodiments, the cell separator 30, such as the cell support 31 and the cell group separator 32, has multiple support positions for supporting the cell units 20, so that the cell units 20 can maintain a stable position within the housing 10, and that there is a certain interval between adjacent cell units 20, providing a certain heat dissipation space for each cell unit 20.

[0116] Following on from the previous text, besides utilizing the moisture locked within the first material surrounding the battery cell for vaporization-liquefaction circulation cooling within the battery pack, the first material or other cooling fluids themselves can also facilitate internal-external circulation cooling of the battery pack. This can similarly improve issues such as heat dissipation, thermal runaway, and heat propagation within the battery pack. (Reference) Figures 8 to 14In this application, the battery pack 100 includes a housing 10, a plurality of battery cell units 20, and a portion of the first material or other cooling fluid 60 in a water-locked state surrounding at least some of the battery cell units 20. The housing 10 also has a pipe interface 11 for an external circulating cooling system to access. After the external circulating cooling system connects to the battery pack 100 through the pipe interface 11 on the housing 10, a path for the first material or other cooling fluid 60 to flow is formed between them. The pipe interface 11 is the port of this flow path. The circulating cooling system can extract the first material or other cooling fluid 60 from the battery pack 100, cool it outside the battery pack 100, and then return the cooled first material or other cooling fluid 60 to the battery pack 100. The cooling fluid 60 can effectively absorb the heat generated on the surface of the battery cell 20 within the battery pack 100. After absorbing heat, it can be transferred to the outside of the battery pack 100 for rapid heat dissipation by the circulating cooling system. After cooling down, it returns to the battery pack 100 to continue absorbing heat, thus quickly and effectively removing the heat generated by the battery cell 20 during battery pack 100 operation in a cyclical manner. It is understood that the placement of the first material 60 in a water-locking state around at least part of the battery cell 20 as described above is a preferred location for achieving circulating heat dissipation. However, the cooling fluid 60 is not limited to the same location within the housing 10. For example, the cooling fluid 60 can also be directly poured into the housing 10.

[0117] In some embodiments, the cooling fluid 60 includes, but is not limited to, water-absorbing resin, liquid water, cooling oil, and fluorinated liquid. The water-absorbing resin, as the first material 60, can be disposed in a water-locked state within the housing 10 at locations such as the periphery of the battery cell unit 20, or it can be disposed at other locations within the housing 10. In some embodiments, the first material 60 may also include materials other than water-absorbing resin, but the first material 60 capable of circulating heat dissipation inside and outside the battery pack 100 must be in a fluid state within the housing 10, for example, in a gel state. In other words, the first material 60 may include water-absorbing fibers, but these fibers cannot dissipate heat outside the battery pack 100 using a circulating heat dissipation system. The cooling fluid 60 can be the first material, but is not limited to it.

[0118] Specifically, such as Figure 10A , Figure 10BAs shown, the pipe interface 11 on the housing 10 of the battery pack 100 may include a pipe inlet 11a and a pipe outlet 11b. At the pipe inlet 11a, the cooling fluid 60, such as the first material, is returned to the battery pack 100 by the circulating cooling system. At the pipe outlet 11b, the cooling fluid 60 is extracted from the battery pack 100 by the circulating cooling system. The circulating cooling system establishes a circulating flow path between the pipe inlet 11a and the pipe outlet 11b. This circulating flow path can be a unidirectional loop, in which the cooling fluid 60 moves circumferentially to circulate and dissipate heat during operation. In some embodiments, the pipe interface 11 may also be bidirectional, with both the extraction and input of the cooling fluid 60 passing through the pipe interface 11, establishing a bidirectional reciprocating path between the circulating cooling system and the pipe interface 11. In some embodiments, the pipe inlet 11a and the pipe outlet 11b may be located on the same side of the battery pack 100 housing 10, for example, both located on the front / rear side of the housing 10, or both located on the left / right side of the housing 10; in some embodiments, the pipe inlet 11a and the pipe outlet 11b may also be located on different sides of the battery pack 100 housing 10, for example, respectively located on the front and rear sides of the housing 10, or respectively located on the left and right sides of the housing 10.

[0119] In some embodiments, the pipe interface 11 has a sealed state and a conductive state. When the external circulating cooling system is not connected to the battery pack 100, the pipe interface 11 can remain in a sealed state, and the cooling fluid 60 cannot leave the battery pack 100 through the pipe interface 11, remaining confined within the battery pack 100 housing 10. However, when the circulating cooling system is connected to the battery pack 100, the pipe interface 11 will change to a conductive state due to the system connection, opening the path for the cooling fluid 60 (such as the first material) to communicate with the outside, allowing the circulating cooling system to extract the cooling fluid 60 out of the battery pack 100. In some embodiments, such as... Figure 13 As shown, a one-way valve 111 is provided at the pipe inlet 11a and pipe outlet 11b to restrict the flow direction of the cooling fluid 60, such as the first material, and to maintain a sealed interface when the circulating heat dissipation system is not connected. Specifically, the one-way valve 111 may consist of a valve body, a valve core, and a spring. When the interface is connected, if the guide is in the permitted direction, the spring is compressed, and the valve core, such as the ball, moves along the valve body to allow the fluid to pass through. If the interface is not connected or is not guided in the permitted direction, the spring extends, causing the valve core, such as the ball, to close the fluid passage with the valve body.

[0120] In some embodiments, the battery pack 100 further includes a retainer 80, which can confine the cooling fluid 60 within the battery pack 100 to a certain space. For example, the retainer 80 can confine the cooling fluid 60 to a sealed space except for the interface to cooperate with the circulating heat dissipation system to achieve circulating movement. When the circulating heat dissipation system is not working, the cooling fluid 60 is held by the retainer 80 within a preset space and is in a state where it does not flow randomly. For example, the retainer 80 can hold the cooling fluid, such as the first material 60 in a water-locked state, around the cell unit 20. When the circulating heat dissipation system is working, the cooling fluid 60 is also held by the retainer 80 within the preset space. However, at this time, the cooling fluid 60 will flow within the preset space and pass through the pipe interface 11 to achieve its own circulating heat dissipation.

[0121] In some embodiments, such as Figure 4 , Figure 11 , Figure 12 As shown above, following the preceding text, the battery pack 100 includes a cell support 31 that supports and separates the cell units 20. This cell support 31 can also serve as the aforementioned retaining member 80 within the battery pack 100. Specifically, the cell support 31 can be positioned around the cell unit 20, located between the housing 11 and the cell unit 20, with the cooling fluid 60 located between the cell support 31 and the cell unit 20. In one embodiment, the cell support 31 can cooperate with components such as the end cap 33 to form a sealed space outside the cell unit 20. Both the cell unit 20 and the cooling fluid 60 are disposed within this sealed space, with the cooling fluid 60 located between the inner wall of the cell support 31 and the outer wall of the cell unit 20. This sealed space has a port that can communicate with the pipe interface 11, allowing the cooling fluid 60 maintained within the sealed space during operation of the circulating cooling system to be extracted or transported back to the battery pack 100 for circulating cooling.

[0122] In other embodiments, the retainer 80 may also be borne by the housing 10, or the retainer 80 may be integrally formed with the housing 10. Specifically, the housing 10 may be a fully sealed housing and have a retaining portion that extends inward to support and block the cell unit 20. The cooling fluid 60 is located between the inner wall of the housing 10 or the housing retaining portion and the outer wall of the cell unit 20. When the circulating heat dissipation system is working, it can be directly drawn out or transported back to the battery pack 100 through the pipe interface 11 on the housing 10.

[0123] In some embodiments, the multiple cell units 20 within the battery pack 100 can each constitute multiple cell modules. The flow path of the cooling fluid 60 under the action of the circulating heat dissipation system can pass through and connect the multiple cell modules, that is, one path runs through multiple cell modules; or, the paths of the cooling fluid 60 through each cell module may not be connected, that is, multiple paths flow through multiple modules respectively, but in this case, the multiple paths can converge at the pipe interface 11. Correspondingly, the aforementioned retaining member 80 can be provided for the multiple cell modules as a whole, or it can be provided for each cell module separately.

[0124] In one alternative implementation, the external circulating cooling system of the battery pack 100 can be housed within the charger 400, thereby effectively dissipating heat from the battery pack 100 during high-temperature charging scenarios. Conversely, the circulating cooling system 420 housed within the charger 400 can also provide circulating cooling for the battery pack 100 in non-battery pack charging scenarios. It is understood that the circulating cooling system for dissipating heat from the cooling fluid 60 within the battery pack 100 may not be housed within the charger 400. In another alternative implementation, the circulating cooling system can also be housed within the power tool 200 to effectively dissipate heat during battery pack discharging scenarios, or the circulating cooling system can be independently housed in a dedicated cooling device.

[0125] In some embodiments where the circulating cooling system 420 is located within the charger 400, the electrical connection between the battery pack 100 and the charger 400 for power transmission, and the mechanical connection for circulating cooling, can be implemented simultaneously. That is, when the battery pack 100 and the charger 400 are plugged in, rapid electrical connection and pipe connection can be achieved simultaneously. Specifically, the battery pack 100 housing 10, in addition to the pipe interface 11, also has a charging interface 12. The pipe interface 11 of the battery pack 100 is mechanically connected to the charger 400, and the charging interface 12 is electrically connected to the charger 400. Furthermore, the electrical connection of the charging interface 12 generally also requires structural connection. In other embodiments, the electrical and mechanical connections between the battery pack 100 and the charger 400 can be asynchronous. For example, the connection between the pipe interface 11 of the battery pack 100 and the circulating cooling system 420 of the charger 400 can also be manually operated, allowing the user to choose the appropriate time to activate the circulating cooling system 420.

[0126] In some embodiments, the circulating cooling system 420 is designed with various verification and control logics during operation. Specifically, the circulating cooling system 420 has startup logic. In some embodiments, before starting operation, the circulating cooling system 420 checks whether the connection between the battery pack 100 pipe interface 11 and the charger 400 cooling system interface 411 (described later) is successful, or further checks the sealing of the interface connection. In some embodiments, the circulating cooling system 420 starts before the battery pack 100 is charged, circulating cooling the battery pack 100 until its temperature drops to a level that meets the charging requirements before charging. In other embodiments, the circulating cooling system 420 starts and continues to operate as the battery pack 100 is charging, or the system monitors the temperature of the battery pack 100 during charging to determine whether to start the circulating cooling system 420 to cool the battery pack 100, operating if the temperature exceeds the limit and stopping the circulating cooling if the temperature does not exceed the limit.

[0127] Correspondingly, such as Figures 9 to 11 As shown, this application also proposes a charger 400. The charger 400 includes a charger housing 410 and a circulating heat dissipation system 420. The charger housing 410 forms the main exterior of the charger 400 and has an internal accommodating space within which the circulating heat dissipation system 420 can be housed. The charger housing 410 also has a heat dissipation system interface 411, and the pipe interface 11 on the upper housing 10 of the battery pack 100 described above can mate with this heat dissipation system interface 411 to form a path for the flow of cooling fluid 60, such as the first material. If a one-way valve is provided at the pipe interface 11, a corresponding structure will be provided at the heat dissipation system interface 411 to achieve one-way flow of the pipe inlet 11a or the pipe outlet 11b. In addition to the heat dissipation system interface 411, the charger housing 400 also has a charger interface 412 for electrical connection with the charging interface 12 of the battery pack 100. In some embodiments, the maximum charging rate of the charger 400 can be greater than or equal to 2C. For example, the charging rate is the ratio between the charging current when the charger 400 can charge the battery pack 100 and the capacity of the battery pack 100. That is, the charger 400 has the ability to quickly charge the battery pack 100 and other electrical devices. When the battery pack 100 is charged by the charger 400, the temperature rise is relatively strong, which increases the necessity of designing the above-mentioned circulating heat dissipation system 420.

[0128] It should be noted that although the charger 400 is equipped with a circulating cooling system 420 to circulate cooling for the battery pack 100, which has an internal cooling fluid 60, it can also charge other ordinary battery packs that do not have a cooling fluid 60. The circulating cooling function and the charging function of the charger 400 can be independent of each other. Similarly, the battery pack 100 with a cooling fluid 60 inside the housing 10 can be charged by the charger 400 equipped with the circulating cooling system 420, or by other ordinary chargers that do not have a circulating cooling system. For example, the battery pack 100 described above, with a first material 60 such as water-absorbing resin disposed around the battery cell 20, can still quickly and effectively remove heat from the surface of the battery cell 20 by utilizing the high latent heat of vaporization of water when the first material 60 is in a water-locked state without the assistance of an external circulating cooling system. This isolates the heat conduction between the surfaces of the battery cells 20, preventing or mitigating thermal runaway and heat propagation. When an external circulating cooling system is in place, the first material such as water-absorbing resin or other cooling fluids 60 can be extracted from the battery pack 100 for external cooling and circulating heat dissipation, further removing heat generated on the surface of the battery cell 20. A preferred implementation of this application is a charging system 500 that combines a battery pack 100 with a cooling fluid 60 with a charger 400 with a circulating cooling system 420. In the charging system 500, circulating heat dissipation and charging can also be performed separately.

[0129] like Figure 12As shown, the aforementioned circulating cooling system 420 may include at least a pump 421 and a connecting pipe 422. The pump 421 drives the movement of the cooling fluid 60, such as the first material, within the circulating cooling system 420. The connecting pipe 422 cooperates with the pipe interface 11 described above and the cooling system interface on the charger 400 or power tool 200, which will be described later, to create a path for the cooling fluid 60 to flow. Specifically, taking the pipe interface 11, which includes a pipe inlet 11a and a pipe outlet 11b, as an example, the operation of the pump 421 can draw the cooling fluid 60 from the pipe outlet 11b and send it into the connecting pipe 422. The pump 421 then drives the cooling fluid 60 through the connecting pipe 422 to circulate within the circulating cooling system 420 for natural and / or auxiliary cooling, until it reaches the pipe inlet 11a and exits the connecting pipe 422, where it is returned to the battery pack 100. In some embodiments, to enable the circulating cooling system 420 to drive the cooling fluid 60, the housing 10 of the battery pack 100 can be a fully sealed housing to achieve the pressure environment required for the pump 421 to operate. In some embodiments, a retaining member 80 or the like can form a sealed space outside the cell unit 20 to confine the cooling fluid 60 and allow it to pass through. The connecting pipe 422 of the circulating cooling system 420 can be connected to the sealed space formed by the retaining member 80 or the like to cooperate with the pump 421 to operate successfully. In some embodiments, the pump 421 in the circulating cooling system 420 can be a plunger pump or a peristaltic pump, which are well adapted to the above scenario. Of course, other types of pumps can also be selected. In some embodiments, the output power of the pump 421 is greater than or equal to 0.1W and less than or equal to 200W. Optionally, the output power of pump 421 can be greater than or equal to 0.1W and less than or equal to 20W, for example, 2 to 5W, or the output power of pump 421 can be greater than or equal to 0.5W and less than or equal to 50W, to ensure that some cooling fluids 60, such as the first material with relatively weak flow, can move smoothly under the drive of pump 421, and that the cooling fluids 60 are not insufficiently cooled due to excessive flow rate. In some embodiments, the circulating cooling system 420 arranged in charger 400 can be powered by the battery pack 100 connected thereto. In other embodiments, the circulating cooling system 420 can also be powered by other external power sources. Specifically, charger 400 can be provided with a voltage conversion circuit corresponding to the voltage requirements of components such as pump 421 in circulating cooling system 420, to convert electrical energy from battery pack 100 or mains power into the appropriate form. In some cases, circulating cooling system 420 can use the internal auxiliary power supply of charger 400.

[0130] In some embodiments, the circulating cooling system 420, in addition to the pump 421 and the connecting pipe 422, also includes a cooling device 423. One end of the device is connected to the pump 421 via the connecting pipe 422, and the other end is connected to the cooling system interface 411 on the charger housing 410 via the connecting pipe 422. This device provides further auxiliary cooling to the cooling fluid 60 in addition to natural cooling. Specifically, driven by the pump 421, the cooling fluid 60 is first drawn from the battery pack 100 through the pipe interface 11, and then enters the connecting pipe 422 inside the charger 400 through the cooling system interface 411. The cooling fluid 60 travels through the connecting pipe 422 and then reaches the cooling device 423. The cooling device 423 dissipates heat from the cooling fluid 60. After cooling, the cooling fluid 60 leaves the cooling device 423, travels through the connecting pipe 422 until it leaves the charger 400 through the cooling system interface 411, and finally returns to the battery pack 100 through the pipe interface 11, completing one cycle of cooling.

[0131] In some embodiments, the heat dissipation device 423 may include one or more of a fan 423a, a condenser 423b, or other heat sinks. In some embodiments, the cooling fluid 60 can dissipate heat directly within the connecting pipe 422. For example, a coiled connecting pipe 422 may be provided in the circulating heat dissipation system 420, and the cooling airflow of the fan 423a passes through the connecting pipe 422 or a relatively dense section of the connecting pipe 422. Heat sinks and the like may also be arranged along the connecting pipe 422 or located in a relatively dense section of the connecting pipe 422. In some embodiments, the cooling fluid 60 may also flow out of the connecting pipe 422 for heat dissipation. For example, the circulating heat dissipation system 420 may also be provided with a cavity or tank for temporary storage of the cooling fluid 60, which is connected to the connecting pipe 422 as a loop in the circulating flow path. Other heat sinks such as the fan 423a, the condenser 423b, and heat sinks may be located near this cavity or tank. Of course, this is just an exemplary description of the heat dissipation device 423. There are many possible implementation methods for the specific type and specific setting of the heat dissipation device 423 in the circulating heat dissipation system 420, which will not be elaborated here.

[0132] Following the preceding text, this application also proposes a charging system 500. The charging system 500 includes a battery pack 100 and a charger 400. The battery pack 100 includes a housing 10, multiple battery cells 20 disposed within the housing 10, and a cooling fluid 60. The housing 10 has a pipe interface 11 for connection to a connecting pipe 422. The charger 400 includes a charger housing 410 and a circulating heat dissipation system 420 disposed within the charger housing 410. The charger housing 410 also has a heat dissipation system interface 411 that connects to the pipe interface 11. After the battery pack 100 and charger 400 are coupled, the pipe interface 11 connects to the heat dissipation system interface 411, allowing the cooling fluid 60 to be drawn out of the battery pack 100 for circulating heat dissipation under the action of the circulating heat dissipation system 420.

[0133] The cooling fluid 60 within the battery pack 100 of the charging system 500 includes, but is not limited to, liquid water, water-absorbing resin in a water-locking state, fluorinated liquids such as perfluorohexanone, and high-flash-point cooling oil, as described above. It can also be other coolants or cooling gases. Furthermore, the charging system 500 is compatible with the various power tools 200 described above. The battery pack 100 can be used to power the power tool 200, and the charger 400 can charge the battery pack 100, serving as a charger for the power tool's battery pack. Other related details can be found in the described battery pack 100 and charger 400 solutions.

[0134] It is understood that although the circulating heat dissipation system 420 is arranged in the charger 400 in the above embodiments, the composition of the circulating heat dissipation system described above, the selection of its components, and its operation are not entirely limited to the charger 400. Referring to the foregoing, circulating heat dissipation systems arranged in other devices can also be deduced by analogy. For example, this application also proposes a power tool system 600, in which the circulating heat dissipation system 220 can also be arranged in the power tool 200.

[0135] The power tool system 600 includes a battery pack 100 and a power tool 200. The battery pack 100 is detachably mounted to the battery mounting section of the power tool 200 and can power the power tool 200. In some embodiments, the same battery pack 100 can power multiple different power tools 200, or the same power tool 200 can be powered by multiple different battery packs 100. In some embodiments, the battery pack 100 can power at least a first type of power tool and a second type of power tool. In one embodiment, the first type of power tool can be a handheld power tool such as a jigsaw, impact wrench, pruning machine, or chainsaw, and the second type of power tool can be an outdoor work vehicle such as a ride-on lawnmower, stand-up lawnmower, or all-terrain vehicle. In some embodiments, the battery pack 100 can also power a third type of power tool, specifically, a table saw, miter saw, or metal cutter.

[0136] The battery pack 100 includes a housing 10 and a plurality of battery cells 20 disposed within the housing 10, as well as a cooling fluid 60 such as a first material. A pipe interface 11 is provided on the housing 10. The power tool includes a tool body 200 and a circulating heat dissipation system 220 disposed within the tool body 200. A heat dissipation system interface 211 is provided on the tool body 200 to interface with the pipe interface 11. In some embodiments, the power tool 200 further includes working attachments such as saw blades or drill bits that actually perform tasks such as cutting, fastening, and grinding, and / or a walking assembly that supports and drives wheeled equipment such as a manned lawnmower. The power tool 200 also includes a working motor that drives the aforementioned working attachments and / or a walking motor that drives the aforementioned walking assembly. The battery pack 100 can supply power to the working motor and / or the walking motor. After the battery pack 100 is coupled to the power tool 200, that is, after the battery pack 100 is installed in the battery mounting part of the power tool body 200, the pipe interface 11 is connected to the heat dissipation system interface 211, and the cooling fluid 60 can be drawn out of the battery pack 100 for circulating heat dissipation under the action of the circulating heat dissipation system 220. In some embodiments, the cooling fluid 60 in the battery pack 100 of the power tool system 500 includes, but is not limited to, the liquid water, water-absorbing resin, perfluorohexanone and other fluorinated liquids, cooling oil, etc., as described above, or other coolants or cooling gases.

[0137] In some embodiments, the pipe interface 11 of the battery pack 100 remains sealed when not connected to the power tool 200. In some embodiments, the pipe interface 11 of the battery pack 100 includes a pipe inlet 11a and a pipe outlet 11b, and one-way valves may be provided at the pipe inlet 11a and the pipe outlet 11b. In some embodiments, a retainer 80 is also provided within the battery pack 100, which confines the cooling fluid 60 near the cell unit 20 so that the cooling fluid 60 can effectively remove heat generated on the surface of the cell unit 20 when the circulating cooling system is operating. In some embodiments, the retainer 80 may include a cell support 31, or the retainer 80 may also be constituted by the housing 10. In some embodiments, the retainer 80 forms a sealed space outside the cell unit 20, and the cooling fluid 60 is confined within this sealed space except for exiting through the pipe interface 11 connected to the retainer. In some embodiments, the housing 10 of the battery pack 100 is a fully sealed housing.

[0138] In some embodiments, the circulating cooling system 220 of the power tool system 500 includes a pump, connecting pipes, or further includes a fan, condenser, heat sink, and other cooling devices. The cooling fluid 60 within the battery pack 100, driven by the pump in the circulating cooling system 220 of the power tool 200, undergoes natural cooling within the system via the pipe interface 11 and the cooling system interface 211 through the connecting pipe, or is further subjected to assisted forced cooling using cooling devices. After cooling, the cooling fluid 60 is then pumped back into the battery pack 100 through the connecting pipe. In some embodiments, the output power of pumps such as plunger pumps and peristaltic pumps in the circulating cooling system 220 of the power tool 200 is greater than or equal to 0.1W and less than or equal to 200W.

[0139] Following the preceding text, this application also proposes an adapter that can be connected between any two of electrical devices such as a battery pack, charger, and power tool, serving as an intermediary for the transmission of electrical energy and information between them. The adapter can perform tasks such as enabling / disabling, power regulation, and protocol conversion. The circulating heat dissipation system described above can also be arranged in this adapter. In this implementation, the adapter includes an adapter housing as its main body and a circulating heat dissipation system disposed within the receiving space formed by the adapter housing. The adapter housing also has a heat dissipation system interface that can connect to the pipe interface 11 of the battery pack 100. Through the interface connection, the cooling fluid 60, such as the first material, inside the battery pack 100 can be extracted from the battery pack 100 for circulating heat dissipation. Other related content can be found in the preceding text and will not be repeated here.

[0140] Besides considerations regarding thermal runaway, waterproofing and insulation performance are also key aspects of battery pack safety. (Refer to...) Figures 2 to 6In this application, the battery pack 100, in addition to the housing 10 and multiple battery cells 20, also includes an insulating layer made of a second material 70 with water-swellable properties. This insulating layer can be applied to at least some of the polar end faces 42 of the battery cells 20. Although insulating materials are generally applied to the parts of the battery pack 100 that require insulation, there are still certain gaps around components such as the polar end face 42, circuit board assembly 50, and electrical connection assembly 40 inside the housing 10 of the battery pack 100. Water seeping into the housing 10 of the battery pack 100 or water evaporating and liquefying inside the housing 10 of the battery pack 100 may remain in the gaps around the electrical components, causing safety hazards. The second material 70 has good water-swellable properties. This physical property indicates that the second material 70 can absorb the water it comes into contact with and expand accordingly. It should also be noted that the water-swellable properties of the second material 70 are different from the water absorption and swelling properties of other materials. The second material 70 has good insulating properties before and after contact with water and does not present an overall "wet" state. The insulating layer made of the second material 70 applied to the polar end face 42 expands upon contact with water after it seeps into the battery pack 100 housing 10. It rapidly absorbs the moisture, expands, and seals the gaps between the cell unit 20 polar end face 42 and the housing 10 or other components, thus ensuring that small amounts of moisture inside the battery pack 100 housing 10 do not interfere with the cell unit 20 polar end face 42, preventing corrosion and creepage. This keeps the relevant areas dry and insulated. Furthermore, after the absorbed moisture evaporates, the second material 70 returns to its initial volume state, allowing for repeated recycling. The insulating layer made of the second material 70 will not degrade at least within the normal lifespan of the battery pack 100.

[0141] The second material 70 can be in the form of a gel. In some embodiments, the insulating layer can be applied by pressure injection or vacuum injection. For example, after the battery cell unit 20 and related components are placed in an opening in the end cap 33 near the polar end face 42 inside the battery pack 100, the insulating layer can be applied through the opening in the end cap 33. In some embodiments, the second material 70 includes water-swellable polyurethane, i.e., water-swellable polyurethane elastomer.

[0142] In some embodiments, the water absorption expansion coefficient of the second material 70 is greater than or equal to 150% and less than or equal to 500%. Alternatively, the water absorption expansion coefficient of the second material 70 is greater than or equal to 200% and less than or equal to 450%. In some embodiments, the water absorption expansion coefficient of the second material 70 is greater than that of the first material 60, and the first material 60 in a water-locking state is disposed on the periphery of at least a portion of the battery cell 20.

[0143] like Figure 4 , Figure 6As shown, in some embodiments, each cell unit 20 has positive and negative electrode connecting pieces 41 located near the polarity end face 42. The insulating layer made of a second material 70 with water-swelling properties is applied at least at and near the electrical connection between the positive and negative electrode connecting pieces 41 and the polarity end face 42, covering the electrical connection between the connecting pieces 41 and the polarity end face 42. In other embodiments, one or more cell units 20 are enclosed within and supported and isolated by the cell support 31 and the end cap 33, with a gap between the cell support 31 and the end cap 33. The insulating layer made of the second material 70 with water-swelling properties is applied at least between the cell support 31 and the end cap 33. In some embodiments, through the application of the insulating layer, the battery pack 100 housing 10 forms a substantially fully sealed space accommodating the plurality of cell units 20. It is understandable that the above-mentioned insulating layer can also be applied to other parts of the battery pack 100 that have insulation requirements. The electrical connection between the positive and negative electrode connecting pieces and the polarity end face 42, as well as the gap between the end cover 33 and the cell support 31, are preferred choices for applying insulating layers to the battery pack 100. However, this does not constitute a limitation on applying insulating layers made of a second material 70 with water-swelling properties to other parts of the battery pack 100.

[0144] In one alternative implementation, such as Figure 4 , Figure 6 As shown, within the battery pack 100, an insulating layer made of a second material 70 with water-swellable properties can be applied to at least the circuit board assembly 50. The circuit board assembly 50 includes a circuit board 51 associated with the cell unit 20 and / or a circuit board 51 associated with a power transmission terminal, wherein the power transmission terminal is at least a terminal and / or interface for performing power transfer within the battery pack 100 and / or between the battery pack 100 and external devices. In some embodiments, the circuit board 51 is plate-shaped, and the insulating layer made of the second material 70 with water-swellable properties can cover at least a portion of the surface of the circuit board 51.

[0145] In one alternative implementation, the scheme described above of providing a first material 60 in a water-locked state around the periphery of the cell unit 20 and the scheme of applying an insulating layer made of a second material 70 with water-swelling properties to at least the polar end face 42 and / or circuit board assembly 50 within the battery pack 100 can be used simultaneously to reduce the corrosion and creepage hazards of water locked within the first material 60, thereby achieving a safety performance improvement that addresses both thermal runaway and insulation issues.

[0146] Following the preceding text, the insulating layer made of the second material 70 with water-swellable properties can also be applied to protect electrical components in the power tool 200 and the power supply unit 300. This application also proposes a power tool 200, which includes a tool housing constituting the main body of the tool's appearance. This tool housing forms a receiving space, within which a motor serving as the prime mover of the power tool 200 and electrical connection components for transmitting electrical energy and data signals are disposed. The insulating layer made of the second material 70 with water-swellable properties can be applied at least to the electrical connection components. In some embodiments, the power tool 200 also includes a circuit board assembly for functional control, also disposed within the receiving space formed by the tool housing. The insulating layer made of the second material 70 with water-swellable properties can also be applied to the circuit board assembly.

[0147] This application also proposes a power supply device 300, which can be portable or hand-pushable. It can directly or indirectly interact with the battery pack 100, charger, adapter, power tool 200, etc., for charging and discharging. The power supply device 300 can be a power receiver or a power supplier. The power supply device 300 has an internal or external power transmission terminal for power exchange, through which power can be transmitted. In some embodiments, the power supply device 300 can be connected to mains power and supply power to the battery pack 100 inserted therein. In other embodiments, the power supply device 300 contains an energy storage device and can supply power to the battery pack 100 inserted therein. In still other embodiments, the power supply device 300 contains an energy storage device and can supply power to the power tool 200. In yet another embodiment, the power supply device 300 contains an energy storage device and can be connected to mains power or receive power from the battery pack 100. The power supply device 300 includes a housing that forms the main body of the device's appearance. This housing has a receiving space. A power processing module performing AC / DC conversion, buck-boost conversion, rectification, and filtering, as well as electrical connection components for transmitting power and data signals, are disposed within this receiving space. An insulating layer made of a second material 70 with water-swelling properties can be applied at least to the electrical connection components. These electrical connection components include, but are not limited to, various types of terminals and / or interfaces, as well as related electronic components and circuitry. In some embodiments, the power supply device 300 is an adapter or power converter, etc.

[0148] The various technical solutions and corresponding embodiments related to the battery packs, chargers, power tools, and other equipment described above can be selectively and adaptively combined without conflict.

[0149] The foregoing has shown and described the basic principles, main features, and advantages of this application. Those skilled in the art should understand that the above embodiments do not limit this application in any way, and all technical solutions obtained by equivalent substitution or equivalent transformation fall within the protection scope of this application.

Claims

1. A battery pack, comprising: case; Multiple battery cell units are disposed within the housing; The battery pack is characterized in that it further includes an insulating layer, which is applied at least to the polar end face of a portion of the battery cell, and the insulating layer is made of a second material that is water-swellable.

2. The battery pack according to claim 1, characterized in that, The battery pack also includes a cell connector, and the insulating layer at least covers the electrical connection between the cell connector and the polarity end face.

3. The battery pack according to claim 1, characterized in that, The battery pack further includes: a cell support for supporting the cell unit; an end cap disposed on the polarity end face; and an insulating layer applied between the cell support and the end cap.

4. The battery pack according to any one of claims 1 to 3, characterized in that, The second material includes water-swellable polyurethane.

5. The battery pack according to claim 1, characterized in that, The water absorption expansion coefficient of the second material is greater than or equal to 150% and less than or equal to 500%.

6. The battery pack according to claim 1, characterized in that, The shell is essentially fully sealed by the second material.

7. The battery pack according to claim 1, characterized in that, The second material retains its insulating properties both before and after swelling upon contact with water.

8. The battery pack according to claim 1, characterized in that, At least a portion of the battery cell is surrounded by a first material in a water-locking state.

9. A battery pack, comprising: case; Multiple battery cell units are disposed within the housing; The power transmission end is configured to perform at least power transmission. The circuit board assembly includes at least a circuit board belonging to the battery cell unit and / or a circuit board belonging to the power transmission end; The battery pack is characterized in that it further includes an insulating layer, which is applied at least to the circuit board assembly, and the insulating layer is made of a second material that is water-swellable.

10. An electric tool, comprising: Tool casing; The motor and electrical connection assembly are housed within the tool housing; The battery pack is configured to power at least the motor. The power tool is characterized in that it further includes an insulating layer, which is applied at least to the electrical connection assembly, and the insulating layer is made of a second material that is water-swellable.

11. A power supply device, comprising: Device casing; The power transmission end is configured to perform at least power transmission. The power processing module is configured to process the transmitted power. An electrical connection assembly is disposed within the housing of the device; The power supply device is characterized in that it further includes an insulating layer, which is applied at least to the electrical connection assembly, and the insulating layer is made of a second material having water-absorbing and swelling properties.

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