Battery monomer, battery device and power utilization device

Abstract

The embodiment of the utility model provides a battery monomer, a battery device and a power utilization device, the battery monomer comprises a shell assembly, a pressure relief mechanism and an electrode assembly, the shell assembly is provided with an accommodating cavity, the inner wall of the accommodating cavity is provided with a discharge groove, and the discharge groove is communicated with the accommodating cavity; the pressure relief mechanism is arranged on the shell assembly; the electrode assembly is arranged in the containing cavity and spaced from the inner wall of the discharge groove, the pressure relief mechanism and the electrode assembly are spaced to form an air guide space, the discharge groove communicates with the air guide space, and at least part of the discharge groove faces the electrode assembly. According to the battery monomer in the embodiment of the invention, a part of a flowing path of emissions generated by thermal runaway is formed through the discharging groove, so that a gap between the electrode assembly and the accommodating cavity is reduced, and the energy density of the battery monomer is improved; and the flow path of the emissions formed in the single battery bodies can meet the flow demand of the emissions.

Description

Technical Field

[0001] This utility model relates to the field of battery technology, specifically to a battery cell, a battery device, and an electrical device. Background Technology

[0002] In related technologies, the space utilization rate inside a battery cell is directly related to its energy density. To improve the space utilization rate inside a battery cell, it is necessary to reduce the gap between the battery cell casing and the electrode components inside the casing.

[0003] However, after a battery cell experiences thermal runaway, the large amount of high-temperature gas generated needs to reach the pressure relief mechanism of the battery cell through the gap between the casing and the electrode assembly. Therefore, reducing the gap between the casing and the electrode assembly hinders the flow of gas generated by thermal runaway within the battery cell, increasing the risk of explosion after thermal runaway. Utility Model Content

[0004] In view of this, the present invention aims to provide a battery cell, battery device, and electrical device that are beneficial to the space utilization within the battery cell while facilitating the flow of gas generated by thermal runaway within the battery cell.

[0005] To achieve the above objectives, the technical solution of this utility model embodiment is implemented as follows:

[0006] This utility model embodiment provides a battery cell, the battery cell comprising:

[0007] The outer casing assembly has a receiving cavity, and the inner wall of the receiving cavity has a discharge groove, which communicates with the receiving cavity;

[0008] A pressure relief mechanism is provided on the housing assembly;

[0009] An electrode assembly is disposed within the receiving cavity and spaced apart from the inner wall of the discharge groove. The pressure relief mechanism is spaced apart from the electrode assembly to form a gas guiding space. The discharge groove is connected to the gas guiding space, and at least a portion of the discharge groove is disposed facing the electrode assembly.

[0010] In this embodiment of the application, the battery cell forms part of the flow path of the emissions generated by thermal runaway through the discharge groove, which helps to reduce the gap between the electrode assembly and the containment cavity and improve the energy density of the battery cell. At the same time, it helps to ensure that the flow path of the emissions formed in the battery cell can meet the flow requirements of the emissions, which helps to suppress the increase of internal pressure after the battery cell undergoes thermal runaway and helps to reduce the risk of the outer casing assembly breaking due to internal pressure.

[0011] In some embodiments, the gas guiding space is located on one side of the electrode assembly along a first direction, and at least a portion of the discharge groove extends along the first direction and is located on the side of the gas guiding space perpendicular to the first direction. This allows the discharge groove to achieve communication with the gas guiding space and orientation towards the electrode assembly with only one side open, thereby simplifying the manufacturing process of the discharge groove and reducing manufacturing costs.

[0012] In some embodiments, the housing assembly includes a housing and a cover assembly, the housing having a receiving space with one side open, the cover assembly covering the open portion of the receiving space to form the receiving cavity together with the housing, the pressure relief mechanism being provided in at least one of the cover assembly and the housing, and the cover assembly having the discharge groove;

[0013] And / or, the housing is provided with the discharge trough.

[0014] This helps to reduce the distance between the electrode assembly and the cover plate kit, and allows the emissions generated by thermal runaway to be guided to the pressure relief mechanism through the discharge channel after impacting the cover plate kit, thus reducing the risk of emissions leakage due to damage to the cover plate kit.

[0015] In some embodiments, the housing is a cylindrical structure, the cover plate assembly is disposed on at least one side of the housing along its axial direction, and at least a portion of the discharge groove is disposed on the housing and extends along the axial direction of the housing. This facilitates the entry of emissions generated by the battery assembly in various regions along the axial direction of the housing into the discharge groove, and facilitates the smooth discharge of emissions generated by thermal runaway from the battery cells; it also facilitates the formation of the discharge groove along the axial direction of the housing, reducing manufacturing costs.

[0016] In some embodiments, there are multiple discharge channels, and at least some of the discharge channels are evenly arranged around the central axis of the housing. This allows emissions generated by a greater area of ​​the electrode assembly along the radial direction of the housing to enter the discharge channels more quickly, improving discharge efficiency and reducing the risk of damage and breakage of the housing from the impact of the emissions.

[0017] In some embodiments, the dimension of the discharge channel along the axial direction of the housing is equal to the dimension of the receiving space along the axial direction of the housing. This allows emissions generated by a greater area of ​​the electrode assembly along the axial direction of the housing to enter the discharge channel more quickly, improving discharge efficiency and reducing the risk of damage and breakage of the housing under the impact of emissions.

[0018] In some embodiments, at least a portion of the discharge channel is located on the inner wall of the receiving space along the radial direction of the housing. A portion of the cover assembly forms a gap with the electrode assembly along the axial direction of the housing. This gap communicates with the venting space. An open portion of the discharge channel communicates with the side of the gap along the radial direction of the housing away from the central axis of the housing. Another portion of the discharge channel is located on the side of the electrode assembly along the radial direction of the housing. This design allows the venting mechanism, regardless of its location on the cover assembly, to discharge the emissions from the discharge channel into the battery cell through the gap, thus improving the flexibility of the venting mechanism's arrangement on the cover assembly.

[0019] In some embodiments, at least a portion of the discharge channel extends along a first direction, and the dimension of the electrode assembly along the first direction is the maximum dimension of the electrode assembly. This allows emissions generated by the electrode assembly to enter the discharge channel more quickly and in greater quantities, improving discharge efficiency and reducing the risk of the housing being damaged or broken by the impact of the emissions.

[0020] In some embodiments, the housing assembly includes a recess and a body portion. One side surface of the body portion forms part of the inner wall of the receiving cavity. The side surface of the recess near the receiving cavity is recessed to form the discharge groove. The side surface of the recess away from the electrode assembly and the side surface of the body portion away from the electrode assembly are located on the same plane or arc surface. This design prevents the discharge groove from forming additional protrusions on the outer surface of the housing assembly, facilitating a more compact arrangement of the battery cells in the battery device and allowing for the modification of existing battery cells to obtain the discharge groove.

[0021] In some embodiments, the contour of the channel wall in a cross-section perpendicular to the extension direction of the discharge channel is arc-shaped. This arc-shaped channel wall helps reduce the likelihood of cracking due to stress concentration during the impact of the discharged material on the channel wall.

[0022] In some embodiments, in a cross-section perpendicular to the extension direction of the discharge channel, the profile formed by the channel walls gradually narrows away from the open position of the discharge channel. This helps to reduce the likelihood of damage to the channel walls due to impact forces during the flow of waste within the discharge channel.

[0023] In some embodiments, the inner wall of the discharge trough includes two first walls extending along the extension direction of the discharge trough. One edge of the first wall perpendicular to its extension direction forms an open position of the discharge trough, and the other edge is connected to the other first wall. This helps to reduce the probability of damage to the trough wall due to the impact force of the discharged material during its flow within the discharge trough, and the structure is simple and compact, facilitating the manufacture of the discharge trough.

[0024] In some embodiments, the inner wall of the discharge channel includes two second walls and one third wall. The second walls extend along the extension direction of the discharge channel, with one edge of the second wall perpendicular to its extension direction forming an open position of the discharge channel, and the other edge connecting to the third wall. The two second walls are opposite to each other and parallel to the open direction of the discharge channel, and the third wall is perpendicular to the open direction of the discharge channel. This allows the discharge channel to accommodate more emissions, increases the amount of emissions transported from the exhaust channel to the air guide space per unit time, and reduces the risk of damage to the housing assembly due to the pressure of the emissions.

[0025] In some embodiments, the battery cell further includes a reinforcing member, at least a portion of which is located within the discharge channel and abuts against at least a portion of the inner wall of the discharge channel. The reinforcing member is made of a material with a melting point of 80°C to 180°C. Thus, on the one hand, by attaching the reinforcing member to the wall of the discharge channel, the wall of the discharge channel can be supported, which helps to improve the structural strength of the casing assembly under normal use of the battery cell and reduces the risk of damage to the casing assembly under stress. On the other hand, the reinforcing member can melt after the battery cell experiences thermal runaway, allowing the emissions to enter the discharge channel.

[0026] In some embodiments, the reinforcing member completely fills the discharge channel. This allows the reinforcing member to provide better support for the channel walls.

[0027] In some embodiments, the ratio of the depth dimension of the discharge channel to the thickness dimension of the housing assembly ranges from 0.3 to 0.6. This is beneficial to ensure that the area of ​​the cross-section of the discharge channel perpendicular to its extension direction meets the flow rate requirements of the discharged waste while reducing the risk of damage to the housing assembly due to the decrease in structural strength caused by the discharge channel.

[0028] And / or, the size range of the open position of the discharge channel perpendicular to the extension direction of the discharge channel is 0.2mm to 2mm. This facilitates the smooth entry and exit of the discharge material from the discharge channel and also helps to reduce the risk of damage to the housing assembly due to the decrease in the structural strength of the housing assembly caused by the discharge channel.

[0029] And / or, the area of ​​the cross section of the discharge trough perpendicular to its extension direction is the first area, and the area of ​​the cross section of the housing assembly located on the same plane as the first area is the second area. The ratio of the first area to the sum of the first area and the second area is in the range of 0.5% to 50%. This is beneficial to ensure that the area of ​​the cross section of the discharge trough perpendicular to its extension direction meets the flow rate requirements of the discharged waste while reducing the risk of damage to the housing assembly due to the decrease in structural strength caused by the discharge trough.

[0030] This application also provides a battery device, which includes a housing and any of the battery cells described in the foregoing embodiments, wherein the battery cells are located inside the housing.

[0031] Thus, by using the battery cells in the aforementioned embodiments, it is beneficial to improve the energy density of the battery device while reducing the risk of the battery device exploding after the battery cells experience thermal runaway.

[0032] This application also provides an electrical device, which includes the battery device in the foregoing embodiments, and the battery device is used to store or provide electrical energy.

[0033] This helps to increase the operating time of electrical devices and reduces the risk of further damage to electrical devices after thermal runaway of the battery. Attached Figure Description

[0034] Figure 1 This is a schematic diagram of an embodiment of the present invention where the electrical device is a vehicle;

[0035] Figure 2 This is a schematic diagram of a battery in one embodiment of the present invention;

[0036] Figure 3 This is a schematic diagram of a single battery cell in the first embodiment of the present invention;

[0037] Figure 4 for Figure 3 A schematic diagram of the Chinese embodiment from another perspective;

[0038] Figure 5 for Figure 3 A cross-sectional diagram of position AA in the middle;

[0039] Figure 6 for Figure 5 A magnified view of the area at position C in the middle;

[0040] Figure 7 for Figure 3 A cross-sectional view of the BB position in the middle;

[0041] Figure 8 for Figure 7 A magnified view of a portion of position D;

[0042] Figure 9 This is a schematic diagram of the housing in the second embodiment of this application;

[0043] Figure 10 for Figure 9 A cross-sectional view of the EE position;

[0044] Figure 11 for Figure 9 A schematic diagram of the Chinese embodiment from another perspective;

[0045] Figure 12 for Figure 11 A magnified view of the middle F position;

[0046] Figure 13 This is a partially enlarged schematic diagram of the housing in the third embodiment of this application, and its enlarged position is... Figure 11 The F positions are the same in all of them;

[0047] Figure 14 This is a partially enlarged schematic diagram of the housing in the fourth embodiment of this application, and its enlarged position is... Figure 11 The F positions are the same in all of them;

[0048] Figure 15 This is a partially enlarged cross-sectional view of a single battery cell in the fifth embodiment of this application, and the enlarged portion is located at the same position as... Figure 7 The position of D in them is the same.

[0049] Explanation of reference numerals in the attached figures

[0050] 10. Battery cell; 11. Casing assembly; 11a. Receiving cavity; 11b. Discharge groove; 11c. Vent space; 11d. Gap; 111. Casing; 111a. Receiving space; 111b. Central axis; 1111. Recess; 1111a. First wall; 1111b. Second wall; 1111c. Third wall; 1112. Body; 112. Cover plate kit; 12. Pressure relief mechanism; 13. Electrode assembly; 14. Reinforcing member; 20. Housing; 21. First housing; 22. Second housing; 100. Battery device; 200. Controller; 300. Motor; 1000. Electrical device. Detailed Implementation

[0051] It should be noted that, in the absence of conflict, the embodiments and technical features in the embodiments of this utility model can be combined with each other. The detailed description in the specific embodiments should be understood as an explanation of the spirit of this utility model and should not be regarded as an improper limitation of this utility model.

[0052] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains; the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the invention; the terms “comprising” and “having”, and any variations thereof, in the specification and the foregoing description of the invention are intended to cover non-exclusive inclusion.

[0053] In the description of the embodiments of this utility model, technical terms such as "first," "second," and "third" are used only to distinguish different objects and should not be construed as indicating or implying relative importance or implicitly specifying the number, specific order, or primary and secondary relationship of the indicated technical features. In the description of the embodiments of this utility model, "multiple" means two or more, unless otherwise explicitly defined.

[0054] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of the present invention. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0055] In the description of this utility model embodiment, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. Additionally, the character " / " in this document generally indicates that the preceding and following related objects are in an "or" relationship.

[0056] In the description of the embodiments of this utility model, for ease of explanation, as shown in the accompanying drawings, the direction of arrow X is referred to as the "first direction" or "axial direction of the housing".

[0057] In the description of the embodiments of this utility model, unless otherwise explicitly specified and limited, technical terms such as "installation," "connection," "joining," and "fixing" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in the embodiments of this utility model according to the specific circumstances.

[0058] In the description of the embodiments of this utility model, unless otherwise explicitly specified and limited, the technical term "contact" should be interpreted broadly, and can be direct contact, contact through an intermediate medium layer, contact between two contacting parties with essentially no interaction force, or contact between two contacting parties with interaction force.

[0059] In this embodiment of the application, the battery cell can be a secondary battery, which refers to a battery cell that can be recharged to activate the active materials and continue to be used after the battery cell has been discharged.

[0060] The battery cell can be a lithium-ion battery, sodium-ion battery, sodium-lithium-ion battery, lithium metal battery, sodium metal battery, lithium-sulfur battery, magnesium-ion battery, nickel-metal hydride battery, nickel-cadmium battery, lead-acid battery, etc., and the embodiments of this application are not limited to this.

[0061] A single battery cell typically includes an electrode assembly. The electrode assembly includes a positive electrode, a negative electrode, and a separator, with the separator positioned between the positive and negative electrodes. During the charging and discharging process of a single battery cell, active ions (such as lithium ions) repeatedly insert and extract between the positive and negative electrodes. The separator, positioned between the positive and negative electrodes, prevents short circuits while allowing active ions to pass through.

[0062] The electrode assembly can be a wound structure, a stacked structure, or a hybrid structure of wound and stacked.

[0063] In some embodiments, the electrode assembly is a wound structure. The positive and negative electrode sheets are wound into a wound structure.

[0064] In some embodiments, the electrode assembly is a stacked structure.

[0065] In some embodiments, multiple positive and negative electrodes may be provided, and multiple positive and multiple negative electrodes may be stacked alternately.

[0066] In some embodiments, multiple positive electrode sheets may be provided, and negative electrode sheets may be folded to form multiple stacked folded segments, with a positive electrode sheet sandwiched between adjacent folded segments.

[0067] In some embodiments, both the positive and negative electrode sheets are folded to form multiple stacked folded segments.

[0068] In some embodiments, multiple separators may be provided, each disposed between any adjacent positive or negative electrode plates.

[0069] In some embodiments, the separator can be continuously disposed between any adjacent positive or negative electrode plates by means of folding or rolling.

[0070] In some embodiments, the electrode assembly may be cylindrical, flat, or polygonal in shape.

[0071] In some embodiments, the electrode assembly has tabs that allow current to be drawn from the electrode assembly. The tabs include a positive tab and a negative tab.

[0072] In some embodiments, the battery cell may include a casing. The casing may be a steel casing, an aluminum casing, a plastic casing (such as a polypropylene casing), a composite metal casing (such as a copper-aluminum composite casing), or an aluminum-plastic film, etc. In some embodiments, the casing may be a sealed structure or a non-sealed structure. In some embodiments, when the casing is a non-sealed structure, the casing serves to protect the electrode assembly, and a sealing bag is included between the casing and the electrode assembly to encapsulate the electrode assembly and electrolyte. Specifically, the sealing bag may be a bag-shaped insulating component or an aluminum-plastic film. When the casing is a sealed structure, it is used to encapsulate components such as the electrode assembly and electrolyte.

[0073] In some embodiments, the battery cell can be a cylindrical battery cell, a prismatic battery cell, a pouch battery cell, or a battery cell of other shapes. Prismatic battery cells include prismatic battery cells, blade-shaped battery cells, and multi-prismatic batteries, such as hexagonal prismatic batteries. This application does not have any particular limitations.

[0074] In some embodiments, the housing includes an end cap and a housing, the housing having an opening, and the end cap covering the opening. The housing may have one or more openings. The end cap may also have one or more.

[0075] In some embodiments, a pressure relief mechanism is provided on the casing. The pressure relief mechanism is used to release the internal gas of the battery cell.

[0076] In some embodiments, the internal pressure or temperature of a battery cell is actuated to release the internal pressure or temperature when it reaches a predetermined threshold. When the internal pressure or temperature of a battery cell reaches the predetermined threshold, the pressure relief mechanism is activated or a weak structure in the pressure relief mechanism is broken, thereby forming an opening or channel for the release of internal pressure or temperature. The threshold design varies depending on design requirements. The threshold may depend on the materials of one or more of the positive electrode, negative electrode, electrolyte, and separator in the battery cell.

[0077] In some embodiments, the pressure relief mechanism may be integrally formed with the housing.

[0078] In some embodiments, the pressure relief mechanism may also be separately configured and connected to the housing.

[0079] The term "actuation" as used in this application refers to the activation or actuation of the pressure relief mechanism to a certain state, thereby releasing the internal pressure and temperature of the battery cell. The actions of the pressure relief mechanism may include, but are not limited to: movement of components within the mechanism to form an exhaust channel, rupture, breakage, tearing, or opening of at least a portion of the mechanism, etc. When the pressure relief mechanism is activated, the high-temperature, high-pressure substances inside the battery cell are discharged as waste from the activated portion. This method allows for pressure and temperature relief of the battery cell under controllable pressure or temperature, thereby preventing potentially more serious accidents.

[0080] In some embodiments, when the outer casing is a non-sealed structure, the pressure relief mechanism can be configured as a through hole to discharge gas inside the battery cell.

[0081] The emissions from battery cells mentioned in the embodiments of this application include, but are not limited to: electrolyte, dissolved or split positive and negative electrode plates, fragments of separators, high-temperature and high-pressure gases generated by the reaction, flames, etc.

[0082] The battery apparatus mentioned in the embodiments of this application may include one or more battery cell assemblies for providing voltage and capacity. A battery cell assembly may include multiple battery cells, which are connected in series, parallel, or mixed connections via a busbar.

[0083] In some embodiments, a battery cell assembly is typically formed by arranging multiple battery cells.

[0084] In some embodiments, the battery cell assembly can be a battery module, which is formed by arranging and fixing multiple battery cells into a single module. In some embodiments, the battery module can be formed by bundling multiple battery cells together with cable ties.

[0085] In some embodiments, the battery device may be a battery pack, which includes a housing and one or more individual battery cells housed within the housing.

[0086] In some embodiments, the battery cell assembly can be a battery module, and the battery cell assembly can be housed in the housing by fixing the battery module in the housing.

[0087] In some embodiments, the battery cell assembly can also be housed in the housing by directly fixing multiple battery cells to the housing.

[0088] In some embodiments, see Figure 2The enclosure may include a first enclosure and a second enclosure. The first enclosure and the second enclosure are fastened together to form a closed space inside the enclosure to house the individual battery cells. Here, "closed" refers to covering or shutting down; it can be sealed or not sealed. The first enclosure may be a top cover or a bottom plate.

[0089] In some embodiments, the enclosure may include a top cover, a frame, and a bottom plate. The top cover and bottom plate are respectively connected to the frame, so that the interior of the enclosure forms an enclosed space to house the individual battery cells.

[0090] In some embodiments, the housing may be part of the vehicle's chassis structure. For example, a portion of the housing may be at least a part of the vehicle's floor, or a portion of the housing may be at least a part of the vehicle's crossbeams and longitudinal beams.

[0091] The technical solutions described in the embodiments of this application are applicable to various electrical devices that use individual battery cells, such as mobile phones, portable devices, laptops, electric vehicles, electric toys, power tools, vehicles, ships, and spacecraft. For example, spacecraft include airplanes, rockets, space shuttles, and spacecraft.

[0092] Figure 1 This application provides a schematic diagram of the structure of an electrical device 1000 as a vehicle, representing one embodiment of the present application. The vehicle can be a gasoline-powered vehicle, a natural gas-powered vehicle, or a new energy vehicle. New energy vehicles can be pure electric vehicles, hybrid electric vehicles, or range-extended vehicles, etc. Figure 1 As shown, a battery device 100 is installed inside the vehicle. The battery device 100 can be located at the bottom, front, or rear of the vehicle. The battery device 100 can be used to power the vehicle; for example, the battery device 100 can serve as the vehicle's operating power source. The vehicle may also include a controller 200 and a motor 300. The controller 200 is used to control the battery device 100 to supply power to the motor 300, for example, to meet the power needs of the vehicle during starting, navigation, and driving.

[0093] In some embodiments, the battery device in this application is suitable for an energy storage device, which includes one or more battery clusters to increase the voltage and capacity of the energy storage device. A battery cluster may include multiple battery devices connected in series via a busbar to increase the voltage of the energy storage device. When the energy storage device includes multiple battery clusters, the multiple battery clusters are connected in parallel to increase the capacity of the energy storage device.

[0094] Energy storage devices can be used in energy storage power stations, wind power generation systems, solar power generation systems, mobile power systems, or temporary power supply systems. Energy storage devices can store electrical energy as needed and output it when appropriate. For example, an energy storage device can store electrical energy during off-peak hours and provide power to relevant users or electrical equipment during peak hours. The energy storage system provided in this application embodiment can be any power system that requires energy storage devices.

[0095] In some embodiments, the energy storage device is an energy storage container or an energy storage cabinet.

[0096] The embodiments of this utility model will now be described in detail.

[0097] A battery cell includes a casing assembly and an electrode assembly. The casing assembly contains a cavity where the electrode assembly is housed and electrolyte is stored. It is understood that the volume of the electrolyte stored in the cavity and the volume of the electrode assembly are directly related to the battery cell's capacity. Therefore, to improve the energy density of the battery cell, it is necessary to increase the proportion of the electrode assembly's volume to the cavity's volume, which in turn requires a smaller gap between the electrode assembly and the inner wall of the cavity.

[0098] Meanwhile, the gap between the electrode assembly and the inner wall of the housing cavity serves to guide the flow of emissions generated by thermal runaway of the battery cell. Specifically, the housing assembly is equipped with a pressure relief mechanism, the triggering area of ​​which is connected to the housing cavity. After thermal runaway of the battery cell, the generated emissions enter the gap between the electrode assembly and the inner wall of the housing cavity. Under the guidance and constraint of the inner wall of the housing cavity, the emissions reach the triggering area of ​​the pressure relief mechanism and trigger the opening of the pressure relief mechanism, thereby discharging them to the outside of the battery cell.

[0099] However, because the gap between the electrode assembly and the inner wall of the containment cavity becomes smaller, less material passes through the gap to reach the pressure relief mechanism per unit time, which can easily cause the pressure inside the containment cavity to increase, increasing the risk of battery cell explosion.

[0100] To address the aforementioned issues, this application aims to provide a battery cell with an additional discharge groove on the inner wall of its housing cavity. The space between the pressure relief mechanism and the electrode assembly communicates with the discharge groove. After thermal runaway occurs in the battery cell, some of the emissions can enter the space between the pressure relief mechanism and the electrode assembly through the discharge groove, and then be discharged from the battery cell through the pressure relief mechanism. This reduces the gap between the electrode assembly and the inner wall of the housing cavity, while also facilitating faster discharge of emissions generated by thermal runaway.

[0101] This application also provides a battery device 100, see reference. Figure 2The battery device 100 includes a housing 20 and a battery cell 10 as described in the previous embodiment, with the battery cell 10 located inside the housing 20.

[0102] Thus, by using the battery cell 10 in the aforementioned embodiments, it is beneficial to improve the energy density of the battery device 100 while reducing the risk of the battery device 100 exploding after the battery cell 10 experiences thermal runaway.

[0103] This application also provides an electrical device 1000, see reference. Figure 1 The electrical device 1000 includes the battery device 100 in the foregoing embodiments, which is used to store or provide electrical energy.

[0104] This helps to increase the operating time of the electrical device 1000 and also reduces the risk of further damage to the electrical device 1000 after the battery device 100 experiences thermal runaway.

[0105] See Figures 3 to 6 , Figure 8 The battery cell 10 in this embodiment specifically includes a housing assembly 11, a pressure relief mechanism 12, and an electrode assembly 13.

[0106] The outer casing assembly 11 is provided with a receiving cavity 11a, and the inner wall of the receiving cavity 11a is provided with a discharge groove 11b, which is connected to the receiving cavity 11a.

[0107] The pressure relief mechanism 12 is located on the housing assembly 11.

[0108] The electrode assembly 13 is disposed in the receiving cavity 11a and spaced apart from the inner wall of the discharge groove 11b. The pressure relief mechanism 12 is spaced apart from the electrode assembly 13 to form a gas guiding space 11c. The discharge groove 11b is connected to the gas guiding space 11c, and at least a portion of the discharge groove 11b is disposed facing the electrode assembly 13.

[0109] The housing assembly 11 is used to form part of the outer contour surface of the battery cell 10.

[0110] The cavity 11a is used to place the electrode assembly 13 and the electrolyte, and the charging and discharging functions of the battery cell 10 are realized through the electrochemical reaction between the electrolyte and the electrode assembly 13.

[0111] The discharge trough 11b is open at least on one side facing the receiving cavity 11a to communicate with the receiving cavity 11a. Material in the receiving cavity 11a can enter the discharge trough 11b through the open position of the discharge trough 11b, and material in the discharge trough 11b can also enter the receiving cavity 11a through the open position of the discharge trough 11b.

[0112] A portion of the pressure relief mechanism 12 is located inside the receiving cavity 11a, and a portion faces the outside of the battery cell 10.

[0113] When the pressure value inside the receiving cavity 11a is lower than the preset opening pressure of the pressure relief mechanism 12, the pressure relief mechanism 12 is in the closed state, and the material inside the receiving cavity 11a is difficult to be discharged to the outside of the battery cell 10 through the pressure relief structure; when the pressure value inside the receiving cavity 11a is not lower than the preset opening pressure of the pressure relief mechanism 12, the pressure relief mechanism 12 is in the open state, and the material inside the receiving cavity 11a is discharged to the outside of the battery cell 10 through the pressure relief mechanism 12.

[0114] The inner wall of the discharge tank 11b is spaced apart from the electrode assembly 13 to reduce the probability of the electrode assembly 13 clogging the discharge tank 11b.

[0115] At least a portion of the discharge tank 11b faces the electrode assembly 13 so that emissions generated by the electrode assembly 13 after thermal runaway of the battery cell 10 can enter the discharge tank 11b.

[0116] The discharge channel 11b and the venting space 11c form a discharge flow path from electrode assembly 13 to discharge channel 11b, venting space 11c, and pressure relief mechanism 12. Therefore, even if the area outside the discharge channel 11b in the inner wall of the receiving cavity 11a is in contact with the electrode assembly 13, at least part of the discharge generated by the thermal runaway of the battery cell 10 can reach the venting space 11c through the discharge channel 11b and then be discharged from the battery cell 10 through the pressure relief mechanism 12.

[0117] In this embodiment, the battery cell 10 forms part of the flow path for emissions generated by thermal runaway through the discharge groove 11b. This helps to reduce the gap between the electrode assembly 13 and the receiving cavity 11a, thereby increasing the energy density of the battery cell 10. At the same time, it helps to ensure that the flow path of emissions formed within the battery cell 10 can meet the flow requirements of the emissions, which helps to suppress the increase in internal pressure after thermal runaway of the battery cell 10, and helps to reduce the risk of the outer casing assembly 11 breaking due to internal pressure.

[0118] The specific number of discharge troughs 11b is not limited; it can be one. (See also...) Figure 3 and Figure 7 There can also be multiple, so that after thermal runaway of the battery cell 10, the emissions generated by more parts of the electrode assembly 13 can enter the discharge tank 11b.

[0119] The specific number of pressure relief mechanisms 12 can be one or more.

[0120] It is understandable that the air guiding space 11c is part of the receiving cavity 11a.

[0121] In some embodiments, see Figure 5and Figure 6 The gas guiding space 11c is located on one side of the electrode assembly 13 along the first direction, and at least a portion of the discharge groove 11b extends along the first direction and is located on the side of the gas guiding space 11c perpendicular to the first direction.

[0122] That is, the discharge trough 11b is open on at least one side perpendicular to the first direction, and part of the open position on that side faces the electrode assembly 13, while the other part faces and communicates with the air guide space 11c.

[0123] This allows the discharge tank 11b to connect to the air guide space 11c and the electrode assembly 13 with only one side open, thereby simplifying the manufacturing process of the discharge tank 11b and reducing manufacturing costs.

[0124] The specific structural form of the outer casing assembly 11 is not limited.

[0125] For example, see Figure 5 The outer casing assembly 11 includes a housing 111 and a cover plate assembly 112. The housing 111 has a receiving space 111a, one side of which is open. The cover plate assembly 112 covers the open position of the receiving space 111a to form a receiving cavity 11a together with the housing 111.

[0126] During the assembly of the battery cell 10, the electrode assembly 13 is first installed into the housing space 111a through the open position of the housing space 111a. Then, the cover plate kit 112 is placed on the open position of the housing space 111a and the cover plate kit 112 and the housing 111 are sealed together so that the housing cavity 11a forms a closed space.

[0127] In some embodiments, the cover assembly 112 is provided with a through-hole for injecting electrolyte into the mounting cavity from the outside of the battery cell 10 after the cover assembly 112 is placed over the open position of the receiving space 111a. After the electrolyte injection is completed, the injection hole is sealed by a sealant.

[0128] The number of cover plate kits 112 can be one or more.

[0129] In some embodiments, the receiving space 111a is open on at least one side along a first direction, and the cover assembly 112 covers the open position of the receiving space 111a along the first direction.

[0130] In some embodiments, see Figure 5 The pressure relief mechanism 12 is located on the cover plate assembly 112.

[0131] In some embodiments where the receiving space 111a is open in a first direction and the pressure relief mechanism 12 is provided on the cover assembly 112, see [reference]. Figure 6The pressure relief mechanism 12 forms a gas guiding space 11c with the electrode assembly 13 along the first direction.

[0132] In some embodiments, the pressure relief structure is located on the housing 111.

[0133] In some embodiments, the cover assembly 112 is provided with a drain groove 11b.

[0134] This helps to reduce the distance between the electrode assembly 13 and the cover plate assembly 112, and allows the emissions generated by thermal runaway to be guided to the pressure relief mechanism 12 through the discharge channel 11b after impacting the cover plate assembly 112, thereby reducing the risk of emissions leakage due to damage to the cover plate assembly 112.

[0135] In some embodiments, the cover assembly 112 is provided with a discharge channel 11b and a pressure relief mechanism 12.

[0136] This allows for faster discharge of emissions through the pressure relief mechanism 12, reducing the risk of damage to the battery cells 10.

[0137] In some embodiments, see Figure 9 and Figure 10 The housing 111 is provided with a discharge trough 11b.

[0138] This helps to reduce the distance between the electrode assembly 13 and the inner wall of the housing space 111a, and allows the emissions generated by thermal runaway to be guided to the pressure relief mechanism 12 through the discharge channel 11b after impacting the inner wall of the housing space 111a, thereby reducing the risk of emissions leakage due to damage to the housing 111.

[0139] In some embodiments, see Figure 9 and Figure 11 The housing 111 has a cylindrical structure, the cover plate assembly 112 is provided on at least one side of the housing 111 along its axial direction, and at least a portion of the discharge groove 11b is provided on the housing 111 and extends along the axial direction of the housing 111.

[0140] That is, the battery cell 10 is a cylindrical battery cell 10. The accommodating space 111a is open on at least one side along the axial direction of the housing 111.

[0141] The cavity 11a of the cylindrical battery cell 10 is also cylindrical, and the electrode assembly 13 can also be roughly formed into a cylinder by winding, so that the shape of the electrode assembly 13 matches the shape of the cavity 111a, reducing the maximum gap size between the electrode assembly 13 and the inner wall of the cavity 11a, which is beneficial to improving the space utilization of the cavity 111a.

[0142] It is understood that the housing 111 is a cylinder, and the discharge groove 11b is located on the inner wall of the radial side of the installation space, which is arc-shaped.

[0143] This facilitates the entry of emissions generated in various regions of the battery assembly along the axial direction of the housing 111 into the discharge groove 11b, and facilitates the smooth discharge of emissions generated by thermal runaway from the battery cell 10; it also facilitates the formation of the discharge groove 11b along the axial direction of the housing 111, thereby reducing manufacturing costs.

[0144] In some embodiments, the first direction is the axial direction of the housing 111.

[0145] In some embodiments where the number of discharge troughs 11b is multiple, see [reference]. Figure 10 and Figure 11 At least a portion of the discharge channels 11b are evenly arranged around the central axis 111b of the shell 111.

[0146] This allows emissions generated in more areas of the electrode assembly 13 along the radial direction of the housing 111 to enter the discharge trough 11b more quickly, which helps improve discharge efficiency and reduces the risk of damage and breakage of the housing 111 under the impact of emissions.

[0147] In some embodiments, see Figure 10 The dimension of the discharge trough 11b along the axial direction of the shell 111 is equal to the dimension of the receiving space 111a along the axial direction of the shell 111. That is, the dimension of the discharge trough 11b along the axial direction of the shell 111 is L1, and the dimension of the receiving space 111a along the axial direction of the shell 111 is L2, where L1 = L2.

[0148] In other words, even if the electrode assembly 13 experiences thermal runaway at the open end of the housing 111 away from the accommodating space 111a along the axial direction of the housing 111, the resulting emissions can directly enter the discharge trough 11b along the radial direction of the housing 111.

[0149] This allows emissions generated in more areas of the electrode assembly 13 along the axial direction of the housing 111 to enter the discharge trough 11b more quickly, which helps improve discharge efficiency and reduces the risk of damage and breakage of the housing 111 under the impact of emissions.

[0150] In some embodiments, see Figure 6At least a portion of the discharge groove 11b is located on the inner wall of the receiving space 111a along the radial direction of the housing 111. A portion of the cover plate assembly 112 and the electrode assembly 13 are spaced apart along the axial direction of the housing 111 to form a gap 11d. The gap 11d communicates with the gas guiding space 11c. An open position of a portion of the discharge groove 11b communicates with the gap 11d on the side away from the central axis 111b of the housing 111 along the radial direction of the housing 111. Another portion of the discharge groove 11b is located on the side of the electrode assembly 13 along the radial direction of the housing 111.

[0151] This forms a discharge flow path from electrode assembly 13 to discharge groove 11b, gap 11d, venting space 11c, and venting mechanism. Specifically, a portion of the discharge enters the discharge groove 11b radially along the housing 111, moves axially along the housing 111 to one end of the discharge groove 11b near the cover plate assembly 112, and then enters the gap 11d radially from a partially open position of the discharge groove 11b, passes through the gap 11d into the venting space 11c, and is finally discharged from the battery cell 10 by the venting mechanism.

[0152] Along the radial direction of the housing 111, a portion of an exhaust trough 11b is located on one side of the void 11d, and an air guide space 11c is located on the other side of the void 11d.

[0153] This allows the venting mechanism to be positioned at any location on the cover plate assembly 112, enabling the discharge material in the discharge slot 11b to be discharged from the battery cell 10 through the gap 11d, thereby improving the flexibility of the venting mechanism's arrangement on the cover plate assembly 112.

[0154] In some embodiments where the receiving space 111a is open on only one side along the axial direction of the housing 111, a portion of the discharge trough 11b is located on the inner wall of the receiving space 111a on the side of the housing 111a away from the open position of the receiving space 111a along the axial direction of the housing 111.

[0155] This facilitates the discharge generated by the electrode assembly 13 at the open end away from the receiving space 111a along the axial direction of the housing 111 into the discharge trough 11b.

[0156] In some embodiments, see Figure 10 At least a portion of the discharge trough 11b extends along a first direction, and the dimension of the electrode assembly 13 along the first direction is the maximum dimension of the electrode assembly 13.

[0157] The maximum dimension of electrode assembly 13 refers to the largest of the three dimensions of electrode assembly 13 along its length, width, and height directions.

[0158] In other words, the dimension of the electrode assembly 13 along the first direction is larger than the dimension of the electrode assembly 13 along any other direction. Therefore, in the event of thermal runaway, the electrode assembly 13 will produce more emissions perpendicular to the first direction.

[0159] This allows the emissions generated by the electrode assembly 13 to enter the discharge tank 11b more quickly and in greater quantities, which helps improve discharge efficiency and reduces the risk of damage and breakage of the housing 111 under the impact of the emissions.

[0160] In some embodiments, the dimension of the housing 111 along the first direction is the maximum dimension of the housing 111.

[0161] In some embodiments, the dimension of the battery cell 10 along the first direction is the maximum dimension of the battery cell 10.

[0162] In some embodiments, see Figure 12 The housing assembly 11 includes a recess 1111 and a body 1112. One side surface of the body 1112 forms part of the inner wall of the receiving cavity 11a. The side surface of the recess 1111 near the receiving cavity 11a is recessed to form a discharge groove 11b. The side surface of the recess 1111 away from the electrode assembly 13 and the side surface of the body 1112 away from the electrode assembly 13 are located on the same plane or arc surface.

[0163] See Figure 12 The dotted line is the dividing line between the recessed part 1111 and the main body part 1112.

[0164] The thickness of the recessed portion 1111 is less than that of the main body portion 1112.

[0165] The recessed portion 1111 is located on the outer surface of the outer shell assembly 11, away from the electrode assembly 13. Similarly, the body portion 1112 is located on the outer surface of the outer shell assembly 11, away from the electrode assembly 13. Viewed from the outside of the outer shell assembly 11, since the outer surfaces of the recessed portion 1111 and the body portion 1112 are on the same plane or curved surface, there is no clear distinction at their junction.

[0166] In this way, the arrangement of the discharge groove 11b will not form an additional protrusion on the outer surface of the housing assembly 11, which is conducive to a more compact arrangement of the battery cell 10 in the battery device 100, and also facilitates the modification of the existing battery cell 10 to obtain the discharge groove 11b.

[0167] In some embodiments that include a housing 111 and a cover assembly 112, see [reference] Figure 11 and Figure 12 The housing 111 includes a recessed portion 1111 and a body portion 1112.

[0168] In some embodiments where the housing 111 has a cylindrical structure, see [reference]. Figure 11 and Figure 12 The side surface of the recessed portion 1111 away from the electrode assembly 13 and the side surface of the body portion 1112 away from the electrode assembly 13 together form the outer arc surface of the housing 111.

[0169] It is understandable that after the emissions enter the discharge tank 11b, they will impact the tank wall of the discharge tank 11b.

[0170] In some embodiments, see Figure 13 In a cross section perpendicular to the extension direction of the discharge trough 11b, the contour formed by the trough wall of the discharge trough 11b is an arc shape.

[0171] Thus, the arc-shaped discharge trough 11b has a lower chance of cracking due to stress concentration during the impact of the discharge material on the trough wall.

[0172] In some embodiments, the arc-shaped profile formed by the wall of the discharge trough 11b is a minor arc to reduce the probability that the open edge of the discharge trough 11b will form a sharp corner and be easily damaged.

[0173] In some embodiments, see Figure 12 In the cross section of the discharge trough 11b perpendicular to its extension direction, the profile formed by the trough wall of the discharge trough 11b gradually narrows in the direction away from the open position of the discharge trough 11b.

[0174] In other words, the distance between the two walls of the discharge trough 11b perpendicular to its open direction, namely L3, gradually decreases in the direction away from the open position of the discharge trough 11b.

[0175] This helps reduce the likelihood of damage to the tank wall caused by the impact force of the emissions during their flow within the discharge tank 11b.

[0176] It is understandable that the contour formed by the wall of the discharge trough 11b is an arc shape, which achieves the purpose of the contour formed by the wall of the discharge trough 11b gradually narrowing in the direction away from the open position of the discharge trough 11b.

[0177] In some embodiments, see Figure 12 The inner wall of the discharge trough 11b includes two first walls 1111a. The first walls 1111a extend along the extension direction of the discharge trough 11b. One side edge of the first wall 1111a perpendicular to its extension direction forms the open position of the discharge trough 11b, and the other side is connected to the other first wall 1111a.

[0178] In other words, in a cross section perpendicular to the extension direction of the discharge trough 11b, the two first walls 1111a are connected to each other to form an included angle.

[0179] This helps reduce the likelihood of damage to the tank wall caused by the impact force of the discharge material flowing in the discharge tank 11b, and the structure is simple and compact, making it easy to manufacture the discharge tank 11b.

[0180] In some embodiments, see Figure 14 The inner wall of the discharge trough 11b includes two second walls 1111b and one third wall 1111c. The second walls 1111b extend along the extension direction of the discharge trough 11b. One side edge of the second wall 1111b perpendicular to its extension direction forms the open position of the discharge trough 11b, and the other side is connected to the third wall 1111c. The two second walls 1111b are opposite to each other and parallel to the open direction of the discharge trough 11b, and the third wall 1111c is perpendicular to the open direction of the discharge trough 11b.

[0181] With the dimensions of the open position of the discharge groove 11b and the depth dimension of the discharge groove 11b being constant, the cross section of the discharge groove 11b perpendicular to its extension direction is increased, which is beneficial to ensure that the connection position between the inner wall of the receiving cavity 11a and the second wall 1111b does not form an acute angle.

[0182] This allows the discharge trough 11b to hold more emissions, increases the amount of emissions transported from the exhaust trough to the air guide space 11c per unit time, and reduces the risk of damage to the housing assembly 11 due to the pressure of the emissions.

[0183] It is understandable that the area of ​​the housing assembly 11 with the discharge groove 11b has lower structural strength compared to other areas due to the reduction in solid structure.

[0184] In some embodiments, see Figure 15 The battery cell 10 also includes a reinforcing member 14, at least a portion of which is located within the discharge channel 11b and is in contact with at least a portion of the inner wall of the discharge channel 11b. The material of the reinforcing member 14 has a melting point of 80°C to 180°C.

[0185] Thus, on the one hand, by having the reinforcing member 14 fit against the wall of the discharge tank 11b, it can support the wall of the discharge tank 11b, which is beneficial to improving the structural strength of the housing assembly 11 under normal use of the battery cell 10 and reducing the risk of the housing assembly 11 being damaged by force; on the other hand, the reinforcing member 14 can melt after the battery cell 10 undergoes thermal runaway, so that the emissions can enter the discharge tank 11b.

[0186] It is understandable that the material of the reinforcing member 14 has a melting point higher than the temperature of the normal operating environment of the battery cell 10, so that the reinforcing member 14 will not melt when the battery cell 10 is in normal operating condition.

[0187] The specific melting point of the material of the reinforcing member 14 can be 80℃, 90℃, 100℃, 110℃, 120℃, 130℃, 140℃, 150℃, 160℃, 170℃, 180℃, etc.

[0188] The specific material of the reinforcing component 14 is not limited, such as plastic.

[0189] In some embodiments, see Figure 15 The reinforcing member 14 is attached to the two sides of the discharge trough 11b perpendicular to its opening direction, so as to provide better support for the walls of the discharge trough 11b.

[0190] In some embodiments, see Figure 15 The reinforcing member 14 is completely filled into the discharge trough 11b.

[0191] This allows the reinforcing member 14 to provide better support for the wall of the discharge trough 11b.

[0192] In some embodiments, see Figure 12 The ratio of the depth of the discharge trough 11b to the thickness of the outer casing assembly 11 ranges from 0.3 to 0.6. That is, 0.3 ≤ L4 / L5 ≤ 0.6.

[0193] The depth direction of the discharge channel 11b is the same as the thickness direction of the housing assembly 11, and both are along the opening direction of the discharge channel 11b.

[0194] This is beneficial to ensure that the area of ​​the cross section of the discharge trough 11b perpendicular to its extension direction meets the flow rate requirements of the discharged waste, while reducing the risk that the housing assembly 11 may be easily damaged due to the decrease in structural strength caused by the discharge trough 11b.

[0195] The ratio of the depth of the discharge trough 11b to the thickness of the outer casing assembly 11 can be 0.3, 0.35, 0.4, 0.45, 0.5, 0.55, 0.6, etc.

[0196] The specific method for measuring the depth of the discharge trough 11b and the thickness of the outer casing assembly 11 is not limited. For example, in an environment with a room temperature of 25°C, the outer casing assembly 11 is cut perpendicular to the extension direction of the discharge trough 11b. The tip of a vernier caliper is brought into contact with the open edge of the discharge trough 11b, and the vernier is moved perpendicular to the opening direction of the discharge trough 11b until it comes into contact with the outer surface of the outer casing assembly 11. The thickness of the outer casing assembly 11 can be obtained by reading the data from the vernier caliper. The tip of a vernier caliper is brought into contact with the bottom wall of the discharge trough 11b, and the vernier is moved perpendicular to the opening direction of the discharge trough 11b until it comes into contact with the outer surface of the outer casing assembly 11. The wall thickness of the discharge trough 11b region can be obtained by reading the data from the vernier caliper. The depth of the discharge trough 11b is obtained by subtracting the wall thickness of the discharge trough 11b region from the thickness of the outer casing assembly 11.

[0197] In some embodiments, see Figure 12 The dimension of the open position of the discharge trough 11b perpendicular to its extension direction ranges from 0.2 mm (millimeters) to 2 mm. That is, 0.2 mm ≤ L6 ≤ 2 mm.

[0198] This facilitates the smooth entry and exit of emissions into and out of the discharge tank 11b, and also helps to reduce the risk of damage to the housing assembly 11 due to the reduced structural strength of the housing assembly 11 caused by the discharge tank 11b.

[0199] The specific value of the dimension of the open position of the discharge trough 11b perpendicular to the extension direction of the discharge trough 11b can be 0.2mm, 0.4mm, 0.5mm, 0.6mm, 0.8mm, 1mm, 1.2mm, 1.4mm, 1.5mm, 1.6mm, 1.8mm, 2mm, etc.

[0200] The specific method for measuring the dimension of the open position of the discharge trough 11b perpendicular to the extension direction of the discharge trough 11b is not limited. For example, in an environment with a room temperature of 25°C, the tip of the vernier caliper is brought into contact with the edge of the opening of the discharge trough 11b perpendicular to the extension direction of the discharge trough 11b. The vernier is moved so that it comes into contact with the other edge of the opening of the discharge trough 11b perpendicular to the extension direction of the discharge trough 11b. The dimension of the open position of the discharge trough 11b perpendicular to the extension direction of the discharge trough 11b can be obtained by reading the data from the vernier caliper.

[0201] In some embodiments, the area of ​​the cross section of the discharge trough 11b perpendicular to its extension direction is the first area, and the area of ​​the cross section of the housing assembly 11 located in the same plane as the first area is the second area. The ratio of the first area to the sum of the first area and the second area ranges from 0.5% to 50%.

[0202] First area, see reference. Figure 12This refers to the area enclosed by the dashed line in the diagram and the boundary line of the wall of the discharge trough 11b. The dashed line is the extension of the boundary line of the inner wall of the receiving cavity 11a on both sides of the open position of the discharge trough 11b.

[0203] The cross-section containing the first area and the cross-section containing the second area are located on the same plane.

[0204] This is beneficial to ensure that the area of ​​the cross section of the discharge trough 11b perpendicular to its extension direction meets the flow rate requirements of the discharged waste, while reducing the risk that the housing assembly 11 may be easily damaged due to the decrease in structural strength caused by the discharge trough 11b.

[0205] The specific values ​​of the ratio of the first area to the sum of the first and second areas are 0.5%, 1%, 3%, 5%, 8%, 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, etc.

[0206] One of the battery cells 10 in this embodiment is described as follows:

[0207] The battery cell 10 includes a housing assembly 11, a pressure relief mechanism 12, an electrode assembly 13, and a reinforcing member 14. The housing assembly 11 includes a housing 111 and a cover plate kit 112. The housing 111 has a cylindrical structure and a receiving space 111a. The receiving space 111a is open on one side along the axial direction of the housing 111. The cover plate kit 112 is placed on the open position of the receiving space 111a to form a receiving cavity 11a together with the housing 111. The pressure relief mechanism 12 is provided on the cover plate kit 112. The inner wall of the receiving cavity 11a is provided with a discharge groove 11b, which communicates with the receiving cavity 11a. The electrode assembly 13 is located in the receiving cavity 11a and is spaced apart from the inner wall of the discharge groove 11b. The pressure relief mechanism 12 and the electrode assembly 13 are spaced apart to form a venting space 11c. At least a portion of the discharge groove 11b is disposed on the housing 111 and extends along the axial direction of the housing 111. There are multiple discharge grooves 11b, and at least a portion of the discharge grooves 11b are evenly arranged around the central axis 111b of the housing 111. The axial dimension of the discharge groove 11b along the housing 111 is equal to the axial dimension of the receiving space 111a along the housing 111. At least a portion of the discharge groove 11b is located on the inner wall of the receiving space 111a along the radial direction of the housing 111. A portion of the cover plate assembly 112 and the electrode assembly 13 are spaced apart along the axial direction of the housing 111 to form a gap 11d, which communicates with the gas guiding space 11c. A portion of the open position of the discharge groove 11b communicates with the side of the gap 11d along the radial direction of the housing 111 away from the central axis 111b of the housing 111. Another portion of the discharge groove 11b is located on one side of the electrode assembly 13 along the radial direction of the housing 111. The axial dimension of the electrode assembly 13 along the housing 111 is the maximum dimension of the electrode assembly 13. The housing 111 includes a recess 1111 and a body 1112. One side surface of the body 1112 forms part of the inner wall of the receiving cavity 11a. The side surface of the recess 1111 near the receiving cavity 11a is recessed to form a discharge groove 11b. The side surface of the recess 1111 away from the electrode assembly 13 and the side surface of the body 1112 away from the electrode assembly 13 are located on the same plane or arc surface. In a cross-section perpendicular to the extending direction of the discharge groove 11b, the contour formed by the groove wall of the discharge groove 11b is arc-shaped. The reinforcing member 14 completely fills the discharge groove 11b. The melting point of the material of the reinforcing member 14 is 80°C to 180°C. The ratio of the depth dimension of the discharge groove 11b to the thickness dimension of the housing assembly 11 ranges from 0.3 to 0.6. The dimension of the open position of the discharge groove 11b perpendicular to the extending direction of the discharge groove 11b ranges from 0.2 mm to 2 mm. The area of ​​the cross section of the discharge trough 11b perpendicular to its extension direction is the first area, and the area of ​​the cross section of the outer shell assembly 11 located on the same plane as the first area is the second area. The ratio of the first area to the sum of the first area and the second area is in the range of 0.5% to 50%.

[0208] The various embodiments / implementations provided by this utility model can be combined with each other without creating contradictions.

[0209] The above description is merely a preferred embodiment of the present utility model and is not intended to limit the embodiments of the present utility model. For those skilled in the art, the embodiments of the present utility model can have various modifications and variations. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the embodiments of the present utility model should be included within the protection scope of the embodiments of the present utility model.

Claims

1. A battery cell, characterized in that, The battery cell includes: The outer casing assembly has a receiving cavity, and the inner wall of the receiving cavity has a discharge groove, which communicates with the receiving cavity; A pressure relief mechanism is provided on the housing assembly; An electrode assembly is disposed within the receiving cavity and spaced apart from the inner wall of the discharge groove. The pressure relief mechanism is spaced apart from the electrode assembly to form a gas guiding space. The discharge groove is connected to the gas guiding space, and at least a portion of the discharge groove is disposed facing the electrode assembly.

2. The battery cell according to claim 1, characterized in that, The gas guiding space is located on one side of the electrode assembly along the first direction, and at least a portion of the discharge groove extends along the first direction and is located on the side of the gas guiding space perpendicular to the first direction.

3. The battery cell according to claim 1, characterized in that, The housing assembly includes a housing and a cover assembly. The housing has a receiving space with one side open. The cover assembly covers the open position of the receiving space to form the receiving cavity together with the housing. The pressure relief mechanism is provided in at least one of the cover assembly and the housing. The cover assembly has the discharge groove. And / or, the housing is provided with the discharge trough.

4. The battery cell according to claim 3, characterized in that, The housing is a cylindrical structure, the cover plate kit is disposed on at least one side of the housing along its axial direction, and at least a portion of the discharge groove is disposed on the housing and extends along the axial direction of the housing.

5. The battery cell according to claim 4, characterized in that, The number of discharge channels is multiple, and at least some of the discharge channels are evenly arranged around the central axis of the shell.

6. The battery cell according to claim 5, characterized in that, The dimension of the discharge trough along the axial direction of the housing is equal to the dimension of the receiving space along the axial direction of the housing.

7. The battery cell according to claim 5, characterized in that, At least a portion of the discharge trough is located on the inner wall of the receiving space along the radial direction of the housing. A portion of the cover plate assembly forms a gap with the electrode assembly along the axial direction of the housing. The gap communicates with the air guiding space. An open position of a portion of the discharge trough communicates with the side of the gap along the radial direction of the housing away from the central axis of the housing. Another portion of the discharge trough is located on the side of the electrode assembly along the radial direction of the housing.

8. The battery cell according to claim 1, characterized in that, At least a portion of the discharge trough extends along a first direction, and the dimension of the electrode assembly along the first direction is the maximum dimension of the electrode assembly.

9. The battery cell according to claim 1, characterized in that, The housing assembly includes a recess and a body. One side surface of the body forms part of the inner wall of the receiving cavity. The side surface of the recess near the receiving cavity is recessed to form the discharge groove. The side surface of the recess away from the electrode assembly and the side surface of the body away from the electrode assembly are located on the same plane or arc surface.

10. The battery cell according to claim 1, characterized in that, In a cross-section perpendicular to the extension direction of the discharge trough, the contour formed by the trough wall is an arc shape.

11. The battery cell according to claim 1, characterized in that, In a cross-section of the discharge trough perpendicular to its extension direction, the profile formed by the trough walls gradually narrows toward the open position of the discharge trough.

12. The battery cell according to claim 11, characterized in that, The inner wall of the discharge trough includes two first walls, which extend along the extension direction of the discharge trough. One side edge of the first wall perpendicular to its extension direction forms an open position of the discharge trough, and the other side is connected to the other first wall.

13. The battery cell according to claim 1, characterized in that, The inner wall of the discharge trough includes two second walls and one third wall. The second walls extend along the extension direction of the discharge trough. One side edge of the second wall perpendicular to its extension direction forms the open position of the discharge trough, and the other side is connected to the third wall. The two second walls are opposite to each other and parallel to the open direction of the discharge trough, and the third wall is perpendicular to the open direction of the discharge trough.

14. The battery cell according to claim 1, characterized in that, The battery cell also includes a reinforcing member, at least a portion of which is located within the discharge trough and is in contact with at least a portion of the inner wall of the discharge trough. The material of the reinforcing member has a melting point of 80°C to 180°C.

15. The battery cell according to claim 14, characterized in that, The reinforcing member completely fills the discharge trough.

16. The battery cell according to any one of claims 1-15, characterized in that, The ratio of the depth dimension of the discharge trough to the thickness dimension of the outer casing assembly ranges from 0.3 to 0.6; And / or, the size of the open position of the discharge trough perpendicular to the extension direction of the discharge trough ranges from 0.2 mm to 2 mm; And / or, the area of ​​the cross section of the discharge trough perpendicular to its extension direction is the first area, and the area of ​​the cross section of the housing assembly located in the same plane as the first area is the second area, and the ratio of the first area to the sum of the first area and the second area is in the range of 0.5% to 50%.

17. A battery device, characterized in that, The battery device includes a housing and a battery cell as described in any one of claims 1-16, wherein the battery cell is located within the housing.

18. An electrical appliance, characterized in that, The electrical device includes the battery device of claim 17, the battery device being used to store or provide electrical energy.

Images