Electrolyte injection nozzle, electrolyte injection apparatus, battery cell, battery, and electric device

Abstract

An electrolyte injection nozzle, an electrolyte injection apparatus, a battery cell, a battery, and an electric device, belonging to the technical field of batteries. The electrolyte injection nozzle comprises an expanding section, and the flow area of the electrolyte injection nozzle in the expanding section increases along the direction from the inlet end of the electrolyte injection nozzle to the outlet end of the electrolyte injection nozzle.

Description

Liquid injection nozzle, liquid injection device, battery cell, battery and electrical device

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application is based on the Chinese patent application with application number 202322279976.4 and application date 2023-08-23, and claims the priority of the above-mentioned Chinese patent application. The entire content of the above-mentioned Chinese patent application is hereby introduced into this application as a reference. Technical Field

[0003] The present application relates to the field of battery technology, and in particular to a liquid injection nozzle, a liquid injection device, a battery cell, a battery, and an electrical device. Background Art

[0004] In recent years, new energy vehicles have experienced rapid development. In the electric vehicle sector, power batteries, as the power source of electric vehicles, play an irreplaceable and important role. Power batteries consist of several battery cells, but the manufacturing efficiency of these cells is relatively low and needs to be improved.

[0005] Summary of the Invention

[0006] The embodiments of the present application provide a liquid injection nozzle, a liquid injection device, a battery cell, a battery, and an electrical device, which can improve the manufacturing efficiency of the battery cell.

[0007] In a first aspect, an embodiment of the present application provides a liquid injection nozzle, which includes an expansion section, and the flow area of ​​the liquid injection nozzle increases in the expansion section along the direction from the inlet end of the liquid injection nozzle to the outlet end of the liquid injection nozzle.

[0008] In the above technical solution, when the electrolyte flows through the injection nozzle, it will pass through the expansion section, which is beneficial to improving the injection efficiency, shortening the injection time, and improving the manufacturing efficiency of the battery cell.

[0009] In some embodiments, the flow area of ​​the inlet end of the liquid injection nozzle is smaller than the flow area of ​​the outlet end of the liquid injection nozzle.

[0010] In the above technical solution, since the flow area at the outlet of the injection nozzle is larger than that at the inlet, the injection area can be effectively increased, thereby improving injection efficiency, shortening injection time, and increasing the production efficiency of battery cells. Furthermore, since the flow area at the outlet of the injection nozzle of the embodiment of the present application is larger than that at the inlet, it is equivalent to a flared outlet, and the outlet resistance is relatively small. Positive pressure can be eliminated during the injection process, thereby reducing the risk of liquid spraying.

[0011] In some embodiments, the expansion section is formed in a gradually diverging shape in which the flow area gradually increases from the inlet end to the outlet end.

[0012] In the above technical solution, by setting the expansion section to a gradually expanding form, it is beneficial to improve the flow characteristics of the electrolyte flowing through the expansion section and reduce the flow resistance loss.

[0013] In some embodiments, the injection nozzle includes a tapered section, which is arranged on the side of the amplification section away from the inlet end. The flow area of ​​the tapered section gradually decreases along the direction from the inlet end to the outlet end, and the minimum cross-sectional end of the tapered section constitutes the outlet end.

[0014] In the above technical solution, the outlet position of the liquid injection nozzle is set to a slightly constricted form, so as to facilitate the coordination between the liquid injection nozzle and the liquid injection port, improve the problem of conductive particles formed by friction and collision between the liquid injection nozzle and the liquid injection port of the battery cell, and reduce the risk of conductive particles entering the shell from the liquid injection port and causing reliability problems to the battery cell assembly, thereby helping to improve the reliability of the battery cell.

[0015] In some embodiments, the flow area of ​​the minimum cross-section end of the tapered section is larger than the flow area of ​​the minimum cross-section end of the expansion section, and the axial length of the tapered section is smaller than the axial length of the expansion section.

[0016] In the above technical solution, it is beneficial to obtain a larger expansion range, thereby improving the injection efficiency, shortening the injection time, and improving the production efficiency of the battery cell, and it is also beneficial to the coordination between the outlet end of the injection nozzle and the injection port, improving the problem of conductive particles formed by friction and collision between the injection nozzle and the injection port of the battery cell, reducing the risk of conductive particles entering the shell from the injection port and causing reliability problems to the battery cell assembly, thereby helping to improve the reliability of the battery cell.

[0017] In some embodiments, the injection nozzle includes a first equal cross-sectional segment, which is connected between the expansion segment and the tapered segment, and the flow area of ​​the first equal cross-sectional segment is equal to the flow area of ​​the maximum cross-sectional end of the tapered segment and the flow area of ​​the maximum cross-sectional end of the expansion segment, and the axial length of the first equal cross-sectional segment is greater than the axial length of the tapered segment.

[0018] In the above technical solution, the axial length of the section of the liquid injection nozzle with a larger flow area is relatively long, thereby more effectively improving the liquid injection efficiency, shortening the liquid injection time, and improving the production efficiency of the battery cell.

[0019] In some embodiments, the outer wall of the tapered section is a smoothly curved surface.

[0020] In the above technical solution, when the injection nozzle and the injection port cooperate, the friction and collision between the tapered section and the injection port of the battery cell can be further reduced, and the problem of conductive particles falling into the injection port can be further reduced, which is conducive to further improving the reliability of the battery cell.

[0021] In some embodiments, the injection nozzle includes a second equal cross-sectional segment, which is connected to the side of the amplification segment away from the outlet end, and the flow area of ​​the second equal cross-sectional segment is equal to the flow area of ​​the minimum cross-sectional end of the amplification segment, and the end of the second equal cross-sectional segment away from the amplification segment constitutes the inlet end.

[0022] In the above technical solution, the structure of the liquid injection nozzle is simple and it is convenient to connect the liquid injection nozzle with the electrolyte supply channel of the liquid injection device.

[0023] In some embodiments, the outlet end of the liquid injection nozzle is formed into an elongated strip shape.

[0024] In the above technical solution, it is beneficial to increase the area of ​​the outlet end while reducing the size occupied by the outlet end of the injection nozzle in multiple directions, which is beneficial for the injection nozzle to cooperate with the relatively thin battery cell and improve the adaptability of the injection nozzle, so as to make full use of the space on the battery cell as much as possible and increase the area of ​​the outlet end of the injection nozzle as much as possible.

[0025] In some embodiments, the cross-sectional shape of the amplification section is consistent with the shape of the outlet end of the injection nozzle.

[0026] In the above technical solution, the shape of the liquid injection nozzle is gradually changed and smoothly transitioned, which is beneficial to improving the flow performance of the electrolyte in the liquid injection nozzle.

[0027] In a second aspect, an embodiment of the present application further provides a liquid injection device, comprising a liquid injection nozzle according to any of the above-mentioned schemes.

[0028] In the above technical solution, the injection efficiency can be improved and the injection time can be shortened.

[0029] On the third aspect, an embodiment of the present application also provides a battery cell, including a shell assembly, a housing cavity in the shell assembly, and a liquid injection port connected to the housing cavity on the shell assembly. The battery cell is injected with liquid using the liquid injection nozzle of any of the above-mentioned schemes, and the liquid injection nozzle injects liquid into the housing cavity through the liquid injection port.

[0030] In the above technical solution, since the liquid is injected using the liquid injection nozzle according to the embodiment of the present application, the liquid injection efficiency can be improved, which is conducive to shortening the manufacturing process of the battery cell.

[0031] In some embodiments, the shape of the filling port matches the shape of the outlet end of the filling nozzle.

[0032] In the above technical solution, the size of the liquid injection port can be fully utilized and the size of the outlet end of the liquid injection nozzle can be made as large as possible, thereby improving the liquid injection efficiency. Moreover, since the shape of the liquid injection port matches the shape of the outlet end of the liquid injection nozzle, it is helpful to improve the leakage problem.

[0033] In some embodiments, the outlet end of the liquid injection nozzle is adapted to be embedded in the liquid injection port.

[0034] In the above technical solution, the liquid injection port can limit and surround the outlet end of the liquid injection nozzle, thereby improving the matching stability between the liquid injection nozzle and the liquid injection port and reducing the chance of leakage during the liquid injection process.

[0035] In some embodiments, the shell assembly has a receiving groove with a notch open in a direction away from the receiving cavity. The shell assembly also has a liquid hole connecting the receiving groove and the receiving cavity, and the notch of the receiving groove constitutes a liquid injection port.

[0036] In the above technical solution, the holding tank can serve as a buffer for the electrolyte, thereby improving problems such as splashing and overflowing of the electrolyte. Moreover, the sidewalls of the holding tank can, to a certain extent, prevent the electrolyte from splashing, reducing external contamination caused by the electrolyte and facilitating rapid injection. Moreover, since the notch of the holding tank is larger than the perforated form, it is beneficial to increase the area of ​​the injection port, thereby facilitating a larger outlet end of the injection nozzle, thereby further improving the injection efficiency.

[0037] In some embodiments, a cross section of the slot section of the receiving slot gradually increases in a direction away from the receiving cavity.

[0038] In the above technical solution, since the notch section of the receiving tank is in a flared form, the problem of electrolyte overflow from the receiving tank can be further reduced. In addition, when the outlet end of the injection nozzle is configured to be embedded in the injection port, the notch section of the receiving tank is set to a flared form, so that the injection nozzle can be easily extended into the notch section of the receiving tank, thereby improving the installation efficiency before injection.

[0039] In some embodiments, the housing assembly includes a housing and a pole structure, the housing defines a receiving cavity, the pole structure is disposed on the housing, and the liquid injection port is disposed on the pole structure.

[0040] In the above technical solution, by providing an injection port on the pole structure that can inject electrolyte into the accommodating cavity, the electrolyte can be injected from the pole structure. There is no need to provide a separate injection port on the battery cell shell, so the injection port does not occupy the space of the shell separately. The pole structure does not need to be reduced in size to avoid the injection port. Therefore, the area of ​​the pole structure and the flow area can be increased without increasing the size of the shell, which is beneficial to reducing the flow resistance and improving the current flow efficiency of the battery cell. Increasing the area of ​​the pole structure is also beneficial to the assembly connection between the pole structure and the shell. In addition, since there is no need to increase the size of the shell to increase the area of ​​the pole structure, it is beneficial to achieve miniaturization and lightweighting of the shell. In addition, since there is no need to provide a separate injection port on the battery cell shell and perform special processing on the shell, it is beneficial to reduce the structural complexity and processing difficulty of the shell. Furthermore, there is no need to partially thicken the shell to weld the sealing nails on it, which can further simplify the structure and processing of the shell. There is also no need to thicken the shell as a whole to weld the sealing nails on it, which helps meet the requirements of lightweight and thin shell, helps improve the energy density of battery cells, and helps reduce the weight and material cost of the shell. In addition, by arranging the liquid injection port on the pole structure, it can be facilitated to manufacture and process the liquid injection port, making it easier to meet the design requirements and application needs in terms of size and shape, which helps to reduce the difficulty and cost of processing the liquid injection port.

[0041] In some embodiments, the shell assembly includes a shell and a pole structure, the shell defines a accommodating cavity, the pole structure includes a pole body and a pole cover, the pole body is installed on the shell, the accommodating groove and the liquid hole are both formed on the pole body, and the pole cover is covered on the notch of the accommodating groove.

[0042] In the above technical solution, before electrolyte injection, the terminal cover plate can be left uninstalled, leaving the slot of the receiving tank open. The slot of the receiving tank can then be injected with electrolyte using a liquid injection nozzle. After injection, the terminal cover plate can be used to seal the slot of the receiving tank, thereby preventing electrolyte leakage from the slot of the receiving tank and improving the reliability of the battery cell. Furthermore, since the terminal cover plate covers the slot of the receiving tank, the assembly and connection of the terminal cover plate and the terminal body are facilitated.

[0043] In some embodiments, the pole body is in an elongated strip shape, and the receiving groove is formed as an elongated strip groove extending from one end to the other end of the pole body in a longitudinal direction.

[0044] In the above technical solution, it is beneficial to fully utilize the space of the pole body to increase the size of the receiving groove and improve the injection efficiency. For example, the outlet end of the injection nozzle is set to match the shape of the notch of the receiving groove, which is beneficial to further improve the injection efficiency.

[0045] In some embodiments, the battery cell includes a cell assembly, the cell assembly includes an active material coating portion received in a receiving cavity, and a conductive portion connected to the active material coating portion, a connecting hole connecting the receiving groove and the receiving cavity is formed on the pole body, there are one or more connecting holes and at least one connecting hole serves as a liquid passage hole, and the conductive portion is passed through at least one connecting hole to be at least partially received in the receiving groove.

[0046] In the above technical solution, by accommodating at least part of the conductive part in the receiving groove, at least part of the conductive part occupies the space in the receiving groove, thereby reducing the space occupied by the conductive part in the receiving cavity, saving space in the receiving cavity to accommodate a larger volume of active material coating part, which is beneficial to improving the energy density of the battery cell, or when the energy density of the battery cell remains unchanged, it is beneficial to reduce the size of the battery cell.

[0047] In a fourth aspect, an embodiment of the present application further provides a battery, comprising a busbar component and a battery cell according to any of the above-mentioned solutions, wherein there are multiple battery cells and at least two of the battery cells are electrically connected via the busbar component.

[0048] In the above technical solution, since the manufacturing efficiency of the battery cell according to the embodiment of the present application is improved, it is beneficial to improve the manufacturing efficiency of the battery and reduce the manufacturing cost of the battery.

[0049] In a fifth aspect, an embodiment of the present application further provides an electrical device comprising a battery according to any of the above-mentioned solutions.

[0050] In the above technical solution, since the manufacturing cost of the battery is reduced, it is beneficial to reduce the use cost of the electrical device. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following is a brief introduction to the drawings required for use in the embodiments. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without creative work.

[0052] FIG1 is a schematic structural diagram of a vehicle provided in some embodiments of the present application;

[0053] FIG2 is an exploded view of the structure of a battery provided in some embodiments of the present application;

[0054] FIG3 is a schematic structural diagram of a battery cell provided in some embodiments of the present application;

[0055] FIG4 is a schematic cross-sectional view of a liquid injection nozzle provided in some embodiments of the present application;

[0056] FIG5 is a schematic diagram of the cooperation between the liquid injection nozzle and the battery cell shown in FIG4 ;

[0057] FIG6 is a left side view of the liquid injection nozzle shown in FIG4;

[0058] FIG7 is a bottom view of the liquid injection nozzle shown in FIG4;

[0059] FIG8 is a schematic orthographic projection diagram of a battery cell provided in some embodiments of the present application;

[0060] FIG9 is a cross-sectional view along line NN in FIG8 ;

[0061] FIG10 is a partial enlarged view of FIG9;

[0062] FIG11 is a schematic cross-sectional view of a battery cell provided in some embodiments of the present application;

[0063] FIG12 is a schematic diagram of the cooperation between the pole body and the conductive portion provided in some embodiments of the present application;

[0064] FIG13 is a schematic diagram of the cooperation between the pole body and the conductive part provided in some embodiments of the present application;

[0065] FIG14 is a schematic diagram of the cooperation between a battery cell and a busbar component provided in some embodiments of the present application.

[0066] Figure markings: vehicle 1000; first direction X; second direction Y; third direction Z; battery 100; controller 200; motor 300; case 101; first case body 1011; second case body 1012; battery cell 102; shell assembly 1021; pole structure 1020; shell 1; accommodating chamber 1A; first shell wall 11; second shell wall 12; pole body 2; accommodating groove 211; connecting hole 22; first connecting hole 221; second connecting hole 222; liquid hole 23; pressure relief structure 1022; pole cover 3; battery cell assembly 7; active material coating portion 71; conductive portion 72; confluence component 103; liquid injection port 1029; liquid injection nozzle 9; inlet end 9a; outlet end 9b; liquid injection channel 91; expansion section 92; tapered section 93; first uniform cross-section section 94; second uniform cross-section section 95. DETAILED DESCRIPTION

[0067] To make the purpose, technical solutions, and advantages of the embodiments of this application more clear, the technical solutions in the embodiments of this application will be clearly described below in conjunction with the drawings in the embodiments of this application. Obviously, the described embodiments are part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0068] Unless otherwise defined, all technical and scientific terms used in this application have the same meanings as commonly understood by those skilled in the art to which this application belongs. The terms used in the specification of this application are for the purpose of describing specific embodiments only and are not intended to limit this application. The terms "including" and "having" and any variations thereof in the specification and claims of this application and the above-mentioned drawings are intended to cover non-exclusive inclusions. The terms "first" and "second" in the specification and claims of this application or the above-mentioned drawings are used to distinguish different objects, rather than to describe a specific order or a primary-secondary relationship.

[0069] References to "embodiments" in this application mean that a particular feature, structure, or characteristic described in connection with the embodiment may be included in at least one embodiment of the application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor does it constitute an independent or alternative embodiment that is mutually exclusive of other embodiments.

[0070] In the description of this application, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," "connected," and "attached" should be understood in a broad sense. For example, they may refer to fixed connections, detachable connections, or integral connections; they may refer to direct connections, indirect connections through an intermediate medium, or internal connections between two components. Those skilled in the art will understand the specific meanings of the above terms in this application based on specific circumstances.

[0071] The term "and / or" in this application simply describes an association between related objects, indicating that three possible relationships exist. For example, A and / or B can represent: A exists alone, A and B exist simultaneously, and B exists alone. In addition, the character " / " in this application generally indicates that the related objects are in an "or" relationship.

[0072] In the embodiments of this application, the same reference numerals represent the same components, and for the sake of brevity, detailed descriptions of the same components in different embodiments are omitted. It should be understood that the thickness, length, width, and other dimensions of the various components in the embodiments of this application, as well as the overall thickness, length, width, and other dimensions of the integrated device shown in the drawings are merely illustrative and should not constitute any limitation on this application.

[0073] The term "plurality" used in this application refers to two or more (including two).

[0074] In this application, battery cells may include lithium-ion secondary batteries, lithium-ion primary batteries, lithium-sulfur batteries, sodium-lithium-ion batteries, sodium-ion batteries, or magnesium-ion batteries, etc., and the embodiments of this application do not limit this. Battery cells may be cylindrical, flat, rectangular, or other shapes, etc., and the embodiments of this application do not limit this. Battery cells are generally divided into three types based on the packaging method: cylindrical battery cells, prismatic battery cells, and soft-pack battery cells, and the embodiments of this application do not limit this.

[0075] The battery referred to in the embodiments of this application refers to a single physical module that includes one or more battery cells to provide higher voltage and capacity. For example, the battery referred to in this application may include a battery module or a battery pack. A battery module generally includes multiple battery cells. A battery pack generally includes a casing for enclosing one or more battery cells or one or more battery modules. The casing prevents liquids or other foreign matter from affecting the charging or discharging of the battery cells.

[0076] A battery cell consists of a housing, a cell assembly, and an electrolyte. The housing holds the cell assembly and electrolyte. The cell assembly includes at least one electrode assembly, which consists of a positive electrode sheet, a negative electrode sheet, and a separator. The electrode assembly can be a wound or stacked structure. A battery cell primarily operates by the movement of metal ions between the positive and negative electrode sheets.

[0077] A positive electrode sheet generally includes a positive current collector and a positive active material layer. The positive active material layer is directly or indirectly coated on the positive current collector. The uncoated positive current collector protrudes from the coated positive current collector, serving as the positive tab. For lithium-ion batteries, for example, the positive current collector can be made of aluminum, and the positive active material layer can be made of lithium cobalt oxide, lithium iron phosphate, ternary lithium, or lithium manganese oxide.

[0078] A negative electrode sheet generally includes a negative electrode current collector and a negative electrode active material layer. The negative electrode active material layer is directly or indirectly coated on the negative electrode current collector. The negative electrode current collector not coated with the negative electrode active material layer protrudes from the negative electrode current collector coated with the negative electrode active material layer, and the negative electrode current collector not coated with the negative electrode active material layer serves as the negative electrode tab. The negative electrode current collector can be made of copper, and the negative electrode active material layer can be made of carbon, silicon, or other materials.

[0079] To ensure that high currents can pass without melting, the positive electrode tabs are multiple and stacked together to form the positive electrode tab portion, and the negative electrode tabs are multiple and stacked together to form the negative electrode tab portion. The housing is provided with pole posts, and the positive electrode tab portion is electrically connected to the positive electrode post, and the negative electrode tab portion is electrically connected to the negative electrode post. For example, the tab portion can be welded to the pole post to form a direct electrical connection between the tab portion and the pole post. For another example, the battery cell assembly can include an adapter plate, and the tab portion is welded to the adapter plate, and the adapter plate is welded to the pole post to form an indirect electrical connection between the tab portion and the pole post.

[0080] The material of the isolation film is not limited, and can be, for example, polypropylene or polyethylene.

[0081] During the production process of battery cells, electrolyte needs to be injected into the shell. To facilitate the injection of electrolyte, an injection port is usually opened on the shell, and the liquid is injected into the injection port through an injection nozzle. In order to prevent the injected electrolyte from leaking, the injection nozzle is usually set to a tubular shape with a pointed lower end, and the pointed part is inserted into the injection port. However, the injection efficiency of this type of injection nozzle is low, and the injection time is long, which affects the production efficiency of the battery cell. Moreover, the injection nozzle in the related art is set to a tubular shape with a pointed lower end, that is, the form of a closed outlet, so the resistance to the electrolyte flowing out of the injection nozzle is large, and positive pressure needs to be applied during the injection process, which poses a risk of spraying.

[0082] In order to improve the above-mentioned technical problems, the present application proposes a liquid injection nozzle. The liquid injection nozzle of the embodiment of the present application is configured to include an amplification section. The flow area of ​​the liquid injection nozzle increases in the amplification section along the direction from the inlet end of the liquid injection nozzle to the outlet end of the liquid injection nozzle, that is, the inlet area of ​​the amplification section is smaller than the outlet area of ​​the amplification section. For example, the amplification section can be in a gradually expanding form or a step-expanding form. In this way, when the electrolyte flows through the liquid injection nozzle, it will pass through a flow channel section that suddenly expands or gradually expands, which is conducive to improving the liquid injection efficiency and shortening the liquid injection production time. It can also reduce the passage resistance in the amplification section, so that no positive pressure is applied during the liquid injection process, which is conducive to reducing the risk of liquid spraying.

[0083] The present invention provides an electric device that uses a battery as a power source. The electric device may be, but is not limited to, a mobile phone, a tablet, a laptop computer, an electric toy, an electric tool, a battery-powered vehicle, an electric car, a ship, a spacecraft, etc. The electric toy may include a fixed or mobile electric toy, such as a game console, an electric car toy, an electric ship toy, and an electric airplane toy, etc. The spacecraft may include an airplane, a rocket, a space shuttle, and a spacecraft, etc.

[0084] For the convenience of description, the following embodiments are described by taking a vehicle 1000 as an example of an electrical device according to an embodiment of the present application.

[0085] Please refer to Figure 1, which is a schematic structural diagram of a vehicle 1000 provided in some embodiments of the present application. The vehicle 1000 can be a fuel vehicle, a gas vehicle or a new energy vehicle. The new energy vehicle can be a pure electric vehicle, a hybrid vehicle or an extended-range vehicle, etc. A battery 100 is provided inside the vehicle 1000, and the battery 100 can be provided at the bottom, head or tail of the vehicle 1000. The battery 100 can be used to power the vehicle 1000. For example, the battery 100 can serve as an operating power source for the vehicle 1000. The vehicle 1000 may also include a controller 200 and a motor 300. The controller 200 is used to control the battery 100 to power the motor 300, for example, for starting, navigating and driving the vehicle 1000.

[0086] In some embodiments of the present application, the battery 100 can serve not only as an operating power source for the vehicle 1000, but also as a driving power source for the vehicle 1000, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle 1000.

[0087] Please refer to Figure 2, which is an exploded view of the structure of the battery 100 provided in some embodiments of the present application. The battery 100 includes a box body 101 and a plurality of battery cells 102, and the battery cells 102 are accommodated in the box body 101. The box body 101 is used to provide an assembly space for the battery cells 102, and the box body 101 can adopt a variety of structures. In some embodiments, the box body 101 may include a first box body 1011 and a second box body 1012, and the first box body 1011 and the second box body 1012 cover each other, and the first box body 1011 and the second box body 1012 jointly define an assembly space for accommodating the battery cells 102. The second box body 1012 can be a hollow structure with one end open, and the first box body 1011 can be a plate-like structure. The first box body 1011 covers the open side of the second box body 1012, so that the first box body 1011 and the second box body 1012 jointly define an assembly space. The first box body 1011 and the second box body 1012 can also be hollow structures with one side open, and the open side of the first box body 1011 covers the open side of the second box body 1012. Of course, the box body 101 formed by the first box body 1011 and the second box body 1012 can be of various shapes, such as a cylinder, a cuboid, etc.

[0088] In the battery 100, multiple battery cells 102 can be connected in series, in parallel, or in a hybrid configuration. A hybrid configuration refers to a combination of series and parallel connections within the multiple battery cells 102. Multiple battery cells 102 can be directly connected in series, in parallel, or in a hybrid configuration, and then the entire structure of the multiple battery cells 102 is housed within the housing 101. Alternatively, the battery 100 can be constructed by first connecting multiple battery cells 102 in series, in parallel, or in a hybrid configuration to form a battery module. The multiple battery modules are then connected in series, in parallel, or in a hybrid configuration to form a single structure, which is then housed within the housing 101. The battery 100 may also include other structures, such as a busbar assembly for electrically connecting the multiple battery cells 102.

[0089] Each battery cell 102 can be a secondary battery or a primary battery; it can also be a lithium-sulfur battery, a sodium-ion battery, or a magnesium-ion battery, but is not limited thereto. The battery cell 102 can be cylindrical, flat, or rectangular. For example, referring to the embodiment shown in FIG3 , the length of the battery cell 102 is a first direction X, the width of the battery cell 102 is a second direction Y, and the height of the battery cell 102 is a third direction Z. The first direction X, the second direction Y, and the third direction Z are mutually perpendicular.

[0090] According to some embodiments of the present application, in combination with Figure 4, the injection nozzle 9 includes an expansion section 92, and the flow area of ​​the injection nozzle 9 increases in the expansion section 92 along the direction from the inlet end 9a of the injection nozzle 9 to the outlet end 9b of the injection nozzle 9, that is, the inlet area of ​​the expansion section 92 is smaller than the outlet area of ​​the expansion section 92. For example, the expansion section 92 can be in a gradually expanding form or a step-expanding form.

[0091] In the above technical solution, since the injection nozzle 9 includes the expansion section 92, the injection flow channel 91 in the injection nozzle 9 includes a flow channel section with a sudden or gradual increase in area. When the electrolyte flows through the injection nozzle 9, it will pass through the flow channel section with a sudden or gradual increase in flow area, which is conducive to improving the injection efficiency and shortening the injection production time. It can also reduce the passage resistance in the expansion section 92, so that positive pressure can be omitted during the injection process, which is conducive to reducing the risk of liquid spraying. Of course, in some cases, if positive pressure is required, it can of course be added, and this is not limited here.

[0092] According to some embodiments of the present application, with reference to FIG4 , the flow area of ​​the inlet end 9a of the liquid injection nozzle 9 is smaller than the flow area of ​​the outlet end 9b of the liquid injection nozzle 9. In other words, the liquid injection nozzle 9 defines a liquid injection channel 91, and the inlet area of ​​the liquid injection channel 91 is smaller than the outlet area of ​​the liquid injection channel 91.

[0093] For example, in combination with Figures 4 and 5, the inlet end 9a of the injection nozzle 9 is connected to the electrolyte supply channel of the injection device, and the outlet end 9b of the injection nozzle 9 is directly connected to the injection port 1029 on the battery cell 102, so that the injection device can transport the electrolyte to the injection channel of the injection nozzle 9 through the supply channel, and the electrolyte entering the injection channel can be injected into the shell 1 of the battery cell 102 through the injection port 1029.

[0094] Among them, because the flow area of ​​the outlet end 9b of the injection nozzle 9 is larger than that of the inlet end 9a, the injection area can be effectively increased, the injection efficiency can be improved, the injection time can be shortened, and the production efficiency of the battery cell 102 can be improved. In addition, the injection nozzle 9 of the embodiment of the present application has a larger flow area at the outlet end 9b than at the inlet end 9a, which is equivalent to a flared outlet. The outlet resistance is relatively small, and positive pressure can be eliminated during the injection process, thereby reducing the risk of liquid spraying.

[0095] In some embodiments of the present application, in conjunction with FIG4 , the amplification section 92 is formed into a gradually expanding shape in which the flow area gradually increases in the direction from the inlet end 9a to the outlet end 9b. Thus, by setting the amplification section 92 to a gradually expanding form, it is beneficial to improve the flow characteristics of the electrolyte flowing through the amplification section 92 and reduce the flow resistance loss. Of course, the present application is not limited to this. For example, the amplification section 92 can also be set to a step-wise expansion form. For example, the amplification section 92 can include a plurality of equal cross-sectional sections, and the areas of the plurality of equal cross-sectional sections are different, and are arranged in order from small to large in the direction from the inlet end 9a to the outlet end 9b to present a step-wise expansion effect.

[0096] In some embodiments of the present application, in conjunction with FIG4 , the injection nozzle 9 includes a tapered section 93, which is located on the side of the expansion section 92 away from the inlet end 9a. The flow area of ​​the tapered section 93 gradually decreases along the direction from the inlet end 9a to the outlet end 9b, and the smallest cross-sectional end of the tapered section 93 constitutes the outlet end 9b. Thus, the outlet position of the injection nozzle 9 is set to a slightly constricted form, thereby facilitating the coordination between the injection nozzle 9 and the injection port 1029, improving the problem of conductive particles formed by friction and collision between the injection nozzle 9 and the injection port 1029 of the battery cell 102, and reducing the risk of conductive particles entering the housing 1 from the injection port 1029 and causing reliability problems for the battery cell assembly 7, thereby facilitating the improvement of the reliability of the battery cell 102.

[0097] For example, in combination with Figure 4, the outer wall of the tapered section 93 is a smooth curved surface, that is, the longitudinal section of the tapered section 93 is an arc or an approximate arc, so that when the injection nozzle 9 and the injection port 1029 are matched, the friction and collision between the tapered section 93 and the injection port 1029 of the battery cell 102 can be further reduced, and the problem of conductive particles falling into the injection port 1029 can be further reduced, which is conducive to further improving the reliability of the battery cell 102.

[0098] For example, the outer wall of the expansion section 92 may be a smooth curved surface or an inclined surface, that is, the longitudinal section of the expansion section 92 may be an inclined surface or an arc or an approximate arc, thereby enabling flexible design.

[0099] In some embodiments of the present application, as shown in Figure 4, the flow area at the minimum cross-sectional end of the tapered section 93 is larger than the flow area at the minimum cross-sectional end of the expansion section 92, and the axial length L3 of the tapered section 93 is smaller than the axial length L2 of the expansion section 92.

[0100] Exemplarily, the inlet to the outlet of the injection nozzle 9 extends in a direction from top to bottom, the expansion section 92 is located above the tapered section 93, the expansion section 92 gradually increases or increases in a step-by-step manner from top to bottom, and the tapered section 93 gradually decreases from top to bottom. The upper end of the expansion section 92 is its minimum cross-sectional end, and the lower end of the tapered section 93 is its minimum cross-sectional end. The area of ​​the lower end of the tapered section 93 is larger than the area of ​​the upper end of the expansion section 92, and the height of the expansion section 92 in the up and down directions is larger than the height of the tapered section 93 in the up and down directions.

[0101] As a result, it is beneficial to obtain a larger expansion range, thereby improving the injection efficiency, shortening the injection time, and improving the production efficiency of the battery cell 102, and it is also beneficial to the coordination between the outlet end 9b of the injection nozzle 9 and the injection port 1029, improving the problem of conductive particles formed by friction and collision between the injection nozzle 9 and the injection port 1029 of the battery cell 102, and reducing the risk of conductive particles entering the shell 1 from the injection port 1029 and causing reliability problems to the battery cell assembly 7, thereby improving the reliability of the battery cell 102.

[0102] In some embodiments of the present application, as shown in FIG4 , the liquid injection nozzle 9 includes a first uniform cross-sectional section 94, which is connected between the expansion section 92 and the tapered section 93, and the flow area of ​​the first uniform cross-sectional section 94 is equal to the flow area at the maximum cross-sectional end of the tapered section 93 and the flow area at the maximum cross-sectional end of the expansion section 92, respectively, and the axial length L4 of the first uniform cross-sectional section 94 is greater than the axial length L3 of the tapered section 93. For example, the expansion section 92, the first uniform cross-sectional section 94, and the tapered section 93 are arranged in sequence from top to bottom, and the flow area of ​​the expansion section 92 increases from top to bottom, while the flow area of ​​the tapered section 93 decreases from top to bottom. The flow area at the upper end of the first uniform cross-sectional section 94 is equal to the flow area at the upper end of the tapered section 93 and the flow area at the lower end of the expansion section 92, respectively, and the height of the first uniform cross-sectional section 94 in the vertical direction is greater than the height of the tapered section 93 in the vertical direction. Therefore, the axial length of the section of the liquid injection nozzle 9 with a larger flow area is relatively long, which can more effectively improve the liquid injection efficiency, shorten the liquid injection time, and improve the production efficiency of the battery cell 102.

[0103] In some embodiments of the present application, the injection nozzle 9 includes a second uniform cross-sectional section 95, which is connected to the side of the amplification section 92 away from the outlet end 9b, and the flow area of ​​the second uniform cross-sectional section 95 is equal to the flow area of ​​the minimum cross-sectional end of the amplification section 92, and the end of the second uniform cross-sectional section 95 away from the amplification section 92 constitutes the inlet end 9a of the injection nozzle 9. For example, the second uniform cross-sectional section 95 and the amplification section 92 are arranged in sequence from top to bottom, and the flow area of ​​the amplification section 92 increases from top to bottom, the flow area of ​​the second uniform cross-sectional section 95 is equal to the flow area of ​​the upper end of the amplification section 92, and the upper end of the second uniform cross-sectional section 95 constitutes the inlet end 9a of the injection nozzle 9. As a result, the structure of the injection nozzle 9 is simple, and it is convenient to connect the injection nozzle 9 to the electrolyte supply channel of the injection device.

[0104] Of course, the present application is not limited thereto. For example, in other embodiments of the present application, at least one of the first uniform cross-section segment 94 , the second uniform cross-section segment 95 , and the tapered segment 93 may be eliminated.

[0105] In some embodiments of the present application, in conjunction with Figures 4, 6 and 7, the outlet end 9b of the injection nozzle 9 is formed into a long strip, that is, the length of the outlet end 9b of the injection nozzle 9 is greater than the width, which is beneficial for increasing the area of ​​the outlet end 9b while reducing the size occupied by the outlet end 9b of the injection nozzle 9 in multiple directions, which is beneficial for the injection nozzle 9 to cooperate with the relatively thin battery cell 102, improve the adaptability of the injection nozzle 9, and make full use of the space on the battery cell 102 as much as possible, and increase the area of ​​the outlet end 9b of the injection nozzle 9 as much as possible. Exemplarily, the outlet end 9b of the injection nozzle 9 is formed into a rectangle, an oblong, or an ellipse. Among them, the oblong can also be called a runway shape, that is, the length of the rectangle is spliced ​​with semicircles at both ends.

[0106] For example, as shown in Figures 3 and 8, the length direction of the battery cell 102 is the first direction X, the width direction of the battery cell 102 is the second direction Y, and the height direction of the battery cell 102 is the third direction Z. When the injection port 1029 is arranged on one side of the battery cell 102 in the third direction, and the size of the battery cell 102 in the first direction X is much larger than the size of the battery cell 102 in the second direction Y, the outlet end 9b of the injection nozzle 9 is set to be a long strip shape, and the length direction of the outlet end 9b of the injection nozzle 9 can be set to be consistent with the first direction X, and the width direction of the outlet end 9b of the injection nozzle 9 can be set to be consistent with the second direction Y, so that the space on the battery cell 102 can be fully utilized and the area of ​​the outlet end 9b of the injection nozzle 9 can be increased as much as possible.

[0107] In some embodiments of the present application, the cross-sectional shape of the amplification section 92 can be set to be consistent with the shape of the outlet end 9b of the liquid injection nozzle 9, thereby facilitating a gradual change in the shape of the liquid injection nozzle 9, a smooth transition, and improving the flow properties of the electrolyte in the liquid injection nozzle 9. For example, when the outlet end 9b of the liquid injection nozzle 9 is formed into a long strip shape, the cross-sectional shape of the amplification section 92 is formed into an elongated structure, that is, the length of the cross-sectional shape of the amplification section 92 is greater than the width. For example, the cross-sectional shape of the amplification section 92 is formed into a rectangular, oblong, or elliptical shape.

[0108] The present application also provides a liquid injection device, including the liquid injection nozzle 9 of any of the above-mentioned solutions. The liquid injection device of the embodiment of the present application can improve liquid injection efficiency and shorten liquid injection time. It is understood that the specific structure of the liquid injection device is not limited, and for example, it can include a container for storing electrolyte, a liquid supply channel connecting the container and the liquid injection nozzle 9, and a control system for controlling whether the liquid supply channel supplies liquid to the liquid injection nozzle 9.

[0109] The present application also proposes a battery cell 102. In conjunction with Figures 8-10, the battery cell 102 includes a shell assembly 1021, which has a accommodating cavity 1A. The shell assembly 1021 has a liquid injection port 1029 connected to the accommodating cavity 1A. In conjunction with Figures 3-7, the battery cell 102 adopts the liquid injection nozzle 9 of any of the above-mentioned schemes to inject liquid, and the liquid injection nozzle 9 injects liquid into the accommodating cavity 1A through the liquid injection port 1029.

[0110] Specifically, the outlet end 9b of the injection nozzle 9 can be aligned with the injection port 1029 on the battery cell 102, for example, the injection nozzle 9 can be inserted into or cover the injection port 1029, and the injection device can be started. The injection device can transport the electrolyte through the injection nozzle 9 to the injection port 1029. The electrolyte injected from the injection port 1029 can be injected into the accommodating cavity 1A, thereby achieving the injection of the battery cell 102. In this way, due to the use of the injection nozzle 9 according to the embodiment of the present application, the injection efficiency can be improved, which is conducive to shortening the process of the battery cell 102.

[0111] In some embodiments of the present application, as shown in Figures 7 and 8, the shape of the liquid injection port 1029 matches the shape of the outlet end 9b of the liquid injection nozzle 9. As a result, the size of the liquid injection port 1029 can be fully utilized, and the size of the outlet end 9b of the liquid injection nozzle 9 can be made as large as possible, thereby improving the liquid injection efficiency. In addition, since the shape of the liquid injection port 1029 matches the shape of the outlet end 9b of the liquid injection nozzle 9, it is helpful to improve the leakage problem.

[0112] It is worth noting that when the shape of the liquid filling port 1029 matches the shape of the outlet end 9b of the liquid filling nozzle 9, in some examples, the outlet end 9b of the liquid filling nozzle 9 can be embedded in the liquid filling port 1029, so as to reduce the fitting gap between the two. In other examples, the outlet end 9b of the liquid filling nozzle 9 can also be covered on the liquid filling port 1029, so as to reduce the contamination of the electrolyte to other positions on the battery cell 102.

[0113] In some embodiments of the present application, as shown in FIG7 , the outlet end 9b of the injection nozzle 9 is adapted to be embedded within the injection port 1029. That is, before injection, the outlet end 9b of the injection nozzle 9 can be inserted into the injection port 1029. Thus, the injection port 1029 can limit and surround the outlet end of the injection nozzle 9, thereby improving the stability of the fit between the injection nozzle 9 and the injection port 1029 and reducing the chance of leakage during the injection process.

[0114] Moreover, when the shape of the liquid injection port 1029 matches the shape of the outlet end 9b of the liquid injection nozzle 9, if the outlet end 9b of the liquid injection nozzle 9 is suitable for being embedded in the liquid injection port 1029, the fitting gap between the two can be reduced, which is conducive to further improving the liquid injection efficiency and reducing the problem of liquid leakage.

[0115] In some embodiments of the present application, as shown in FIG9 , the housing assembly 1021 includes a receiving groove 211 with a notch open in a direction away from the receiving chamber 1A. The housing assembly 1021 also includes a liquid passage hole 23 connecting the receiving groove 211 with the receiving chamber 1A. The notch of the receiving groove 211 constitutes a liquid injection port 1029. Thus, when electrolyte is injected into the battery cell 102, the electrolyte injected from the injection nozzle 9 first flows into the receiving groove 211 through the notch of the receiving groove 211 (i.e., the liquid injection port 1029). The electrolyte entering the receiving groove 211 then flows toward the receiving chamber 1A via the liquid passage hole 23.

[0116] Thus, the receiving tank 211 can play the role of caching the electrolyte to improve the problems of electrolyte splashing and overflowing. Moreover, the side wall of the receiving tank 211 (i.e., the tank wall extending from the notch of the receiving tank 211 toward the receiving chamber 1A) can block the electrolyte from splashing to a certain extent, reduce the pollution caused by the electrolyte to the outside, and facilitate rapid injection. Moreover, since the notch of the receiving tank 211 is relatively large in area relative to the perforation, it is beneficial to increase the area of ​​the injection port 1029, thereby facilitating the enlargement of the outlet end 9b of the injection nozzle 9, thereby further improving the injection efficiency.

[0117] In some embodiments of the present application, as shown in FIG7 , the cross-section of the notch section of the receiving tank 211 gradually increases in size as it moves away from the receiving cavity 1A, i.e., the notch section of the receiving tank 211 is in a flared form. In the above technical solution, since the notch section of the receiving tank 211 is in a flared form, the problem of electrolyte overflow from the receiving tank 211 can be further reduced. In addition, when the outlet end 9b of the liquid injection nozzle 9 is configured to be embedded in the liquid injection port 1029, the notch section of the receiving tank 211 is configured to be in a flared form, so that the liquid injection nozzle 9 can be easily inserted into the notch section of the receiving tank 211, thereby improving the installation efficiency before liquid injection.

[0118] It is worth noting that the location of the liquid injection port 1029 on the shell assembly 1021 is not limited. For example, when the battery cell 102 needs to be injected, the battery cell 102 can be placed so that the liquid injection port 1029 is located at the top of the shell assembly 1021. At this time, the electrolyte injected into the liquid injection port 1029 through the liquid injection nozzle 9 can enter the accommodating cavity 1A downward, thereby improving the convenience of liquid injection and reducing the probability of electrolyte overflow and splashing. When the battery cell 102 is working, the liquid injection port 1029 can be sealed. At this time, the battery cell 102 can be placed so that the liquid injection port 1029 is located at any position of the shell assembly 1021. For example, when the battery cell 102 is working, the liquid injection port 1029 can be located at the top, bottom, side, etc. of the shell assembly 1021.

[0119] In some embodiments of the present application, as shown in FIG10 , the housing assembly 1021 may include a housing 1 and a pole structure 1020 , wherein the housing 1 defines a receiving cavity 1A, the pole structure 1020 is disposed in the housing 1 , and the liquid injection port 1029 is disposed on the pole structure 1020 .

[0120] According to the battery cell 102 of the embodiment of the present application, by providing an injection port 1029 on the pole structure 1020 for injecting electrolyte into the accommodating cavity 1A, the electrolyte is injected from the pole structure 1020, eliminating the need to separately provide the injection port 1029 on the housing 1 of the battery cell 102. Therefore, the injection port 1029 does not occupy the space of the housing 1 separately, and the pole structure 1020 does not need to be reduced in size to avoid the injection port 1029. Thus, the area and flow area of ​​the pole structure 1020 can be increased without increasing the size of the housing 1, which is beneficial for reducing flow resistance and improving the current flow efficiency of the battery cell 102. Furthermore, increasing the area of ​​the pole structure 1020 also facilitates the assembly and connection of the pole structure 1020 with the housing 1. Furthermore, since the size of the housing 1 does not need to be increased to increase the area of ​​the pole structure 1020, the housing 1 is miniaturized and lightweight.

[0121] Furthermore, since there is no need to separately open the liquid injection port 1029 on the shell 1 of the battery cell 102 and perform special processing on the shell 1, the structural complexity and processing difficulty of the shell 1 are reduced. Furthermore, there is no need to partially thicken the shell 1 in order to weld the sealing nails on the shell 1, which can further simplify the structure and processing of the shell 1. There is also no need to thicken the shell 1 as a whole in order to weld the sealing nails on the shell 1. This helps meet the requirements for thinness and lightness of the shell 1, helps improve the energy density of the battery cell 102, and helps reduce the weight and material cost of the shell 1. Moreover, by arranging the liquid injection port 1029 on the pole structure 1020, the manufacturing and processing of the liquid injection port 1029 can be facilitated, so that the size and shape of the liquid injection port 1029 can more easily meet the design requirements and application needs, which helps reduce the processing difficulty and processing cost of the liquid injection port 1029.

[0122] It is worth noting that the structure of the pole structure 1020 and the form of the liquid injection port 1029 provided thereon are not limited and can be specifically designed according to actual conditions. For example, in some specific embodiments, the liquid injection port 1029 can be in the form of a perforation penetrating the pole structure 1020, thereby simplifying the structure.

[0123] For another example, in some specific embodiments, when the liquid injection port 1029 is formed by the notch of the receiving tank 211, as shown in Figures 10 and 11, the housing assembly 1021 includes a housing 1 and a pole structure 1020. The housing 1 defines a receiving chamber 1A. The pole structure 1020 includes a pole body 2 and a pole cover 3. The pole body 2 is mounted on the housing 1. The receiving tank 211 and the liquid hole 23 are both formed on the pole body 2. The pole cover 3 covers the notch of the receiving tank 211. Therefore, before liquid injection, the pole cover 3 can be left uninstalled, leaving the notch of the receiving tank 211 open. The liquid injection nozzle 9 can be used to inject liquid into the notch of the receiving tank 211. After liquid injection, the pole cover 3 can be used to seal the notch of the receiving tank 211, thereby preventing leakage of electrolyte from the notch of the receiving tank 211 and improving the reliability of the battery cell 102. Particularly, since the pole cover 3 is covered in the notch of the accommodating groove 211 , the pole cover 3 is easily assembled and connected with the pole body 2 .

[0124] Furthermore, by providing the terminal structure 1020 with a receiving groove 211 and a liquid hole 23 for injecting electrolyte into the receiving cavity 1A, electrolyte injection is achieved through the terminal structure 1020, eliminating the need for a separate liquid injection port 1029 on the housing 1 of the battery cell 102. Consequently, the liquid injection port 1029 does not occupy separate space within the housing 1, and the terminal structure 1020 does not need to be reduced in size to accommodate the liquid injection port 1029. This allows the area and flow area of ​​the terminal structure 1020 to be increased without increasing the size of the housing 1, thereby facilitating reduced flow resistance and improved current flow efficiency of the battery cell 102. Furthermore, increasing the area of ​​the terminal structure 1020 also facilitates assembly and connection between the terminal structure 1020 and the housing 1. Furthermore, since the size of the housing 1 does not need to be increased to accommodate the area of ​​the terminal structure 1020, miniaturization and lightweighting of the housing 1 are facilitated.

[0125] It is worth noting that the assembly connection method of the pole cover plate 3 and the pole body 2 is not limited, for example, it can be welding (such as fusion welding or brazing, etc.) or bonding, etc. For example, the pole cover plate 3 is connected to the pole body 2 by laser welding, but the laser welding of the pole cover plate 3 and the pole body 2 has high requirements for the cleanliness of the notch section of the receiving groove 211. If there is residual electrolyte in the notch section of the receiving groove 211, the electrolyte is easily vaporized by heat, and the waste gas generated by the vaporization will rush out of the welding pool and cause defects such as pinholes and explosion points in the weld. In some embodiments of the present application, by setting the notch section of the receiving groove 211 to a flared form, the problem of liquid accumulation in the notch section of the receiving groove 211 can be reduced, thereby facilitating the improvement of the welding yield of the pole cover plate 3 and the pole body 2.

[0126] In some embodiments of the present application, as shown in FIG8 , the pole body 2 is elongated, i.e., the length of the pole body 2 is greater than its width, and the receiving groove 211 is formed as an elongated groove extending from one end of the length of the pole body 2 to the other end. For example, at least one of the cross-sections of the pole body 2 and the receiving groove 211 is rectangular, oblong, or elliptical. The oblong shape can also be called a racetrack shape, i.e., a rectangular shape with semicircles joined at each end.

[0127] In the above technical solution, the setting of the receiving groove 211 is conducive to making full use of the space of the pole body 2 to increase the size of the receiving groove 211 and improve the injection efficiency. Combined with Figures 7 and 8, if the outlet end 9b of the injection nozzle 9 is set to match the notch shape of the receiving groove 211, it is conducive to further improving the injection efficiency.

[0128] In some embodiments of the present application, as shown in FIG10 , the battery cell 102 includes a cell assembly 7, and the cell assembly 7 includes an active material coating portion 71 housed in the accommodating cavity 1A, and a conductive portion 72 connected to the active material coating portion 71. Exemplarily, the conductive portion 72 can be connected to the pole body 2 to form an electrical connection, thereby realizing the output of the cell assembly 7 from the electrode at the pole body 2. For example, the conductive portion 72 can be welded to the pole body 2 to achieve connection. It is understandable that the active material coating portion 71 may include a current collector coated with an active material layer, and the conductive portion 72 may include only a pole ear portion, or may also include a pole ear portion and a transition piece electrically connected to the pole ear portion, etc., and there is no limitation here.

[0129] As shown in Figure 10, a connecting hole 22 connecting the accommodating groove 211 and the accommodating cavity 1A is formed on the pole body 2. There are one or more connecting holes 22 and at least one connecting hole 22 serves as a liquid hole 23. The conductive part 72 is passed through at least one connecting hole 22 to be at least partially received in the accommodating groove 211. Exemplarily, a receiving groove 211 and a connecting hole 22 are formed on the pole body 2, the receiving groove 211 is open in a direction away from the receiving chamber 1A to connect with the outside of the shell 1, the connecting hole 22 is located on the side of the receiving groove 211 close to the receiving chamber 1A, the connecting hole 22 passes through the groove wall on the side of the receiving groove 211 close to the receiving chamber 1A to connect the receiving groove 211 and the receiving chamber 1A, at least one connecting hole 22 is a liquid hole 23, the conductive part 72 can pass through the connecting hole 22 serving as the liquid hole 23 (that is, the connecting hole 22 through which the conductive part 72 passes can still be used for the flow of electrolyte after passing through the conductive part 72), or can pass through the connecting hole 22 that does not serve as the liquid hole 23 (that is, the connecting hole 22 through which the conductive part 72 passes cannot be used for the flow of electrolyte after passing through the conductive part 72).

[0130] Therefore, by accommodating at least part of the conductive part 72 in the receiving groove 211, at least part of the conductive part 72 occupies the space in the receiving groove 211, thereby reducing the space occupied by the conductive part 72 in the receiving cavity 1A, saving space in the receiving cavity 1A to accommodate a larger volume of the active material coating part 71, which is beneficial to improving the energy density of the battery cell 102, or when the energy density of the battery cell 102 remains unchanged, it is beneficial to reduce the size of the battery cell 102.

[0131] In some embodiments, referring to FIG. 12 , the communicating hole 22 through which the conductive portion 72 is passed is a first communicating hole 221 (i.e., at least one communicating hole 22 through which the conductive portion 72 is passed is the first communicating hole 221). At least the first communicating hole 221 can serve as the liquid passage 23. Thus, when the electrode body 2 has the first communicating hole 221 through which the conductive portion 72 passes, regardless of whether the electrode body 2 has the second communicating hole 222 not through which the conductive portion 72 is passed, as described later, the first communicating hole 221 through which the conductive portion 72 is passed also serves as the liquid passage. That is, the first communicating hole 221 through which the conductive portion 72 is passed also provides a liquid passage space. During liquid injection, after the electrolyte is injected into the receiving tank 211, at least a portion of the electrolyte can flow into the receiving chamber 1A from the first communicating hole 221 through which the conductive portion 72 is passed.

[0132] In some embodiments, in combination with Figure 13, the connecting hole 22 with the conductive part 72 is a first connecting hole 221, and the connecting hole 22 is multiple and also includes at least one second connecting hole 222 that is not penetrated by the conductive part 72 (that is, at least one connecting hole 22 is not penetrated by the conductive part 72, and the connecting hole 22 that is not penetrated by the conductive part 72 is the second connecting hole 222), and at least the second connecting hole 222 can be used as the liquid hole 23.

[0133] For example, when the first connecting hole 221 also takes into account the liquid passing function (that is, the first connecting hole 221 still has a liquid passing gap after passing through the conductive part 72), the first connecting hole 221 and the second connecting hole 222 both serve as liquid passing holes 23. When injecting liquid, after the electrolyte is injected into the containing tank 211, a part of it can flow into the containing cavity 1A from the first connecting hole 221 through which the conductive part 72 is passed, and a part of it can flow into the containing cavity 1A from the second connecting hole 222 without which the conductive part 72 is not passed.

[0134] For another example, when the first connecting hole 221 does not have a liquid-passing function (i.e., the first connecting hole 221 is blocked and cannot pass liquid after passing through the conductive portion 72), only the second connecting hole 222 serves as the liquid-passing hole 23. When injecting liquid, after the electrolyte is injected into the containing tank 211, it only flows into the containing cavity 1A from the second connecting hole 222 that does not penetrate the conductive portion 72.

[0135] In the embodiment of the present application, when at least the first communicating hole 221 is used as the liquid passage hole 23, the first communicating hole 221 also has the liquid passage function, that is, after the first communicating hole 221 is penetrated by the conductive portion 72, it can be used to pass the electrolyte. At this time, at least the first communicating hole 221 can be used to pass the electrolyte, so that it can be selected as needed whether to set a communicating hole 22 (such as the second communicating hole 222) that is not penetrated by the conductive portion 72, which is beneficial to reduce the total number of communicating holes 22 opened, thereby simplifying the structure and processing of the pole body 2 and improving the structural strength of the pole body 2.

[0136] In the embodiment of the present application, when at least the second communicating hole 222 serves as the liquid passage 23, the electrolyte can be passed through at least the second communicating hole 222. In this case, the first communicating hole 221 does not need to have a larger diameter or number to allow the electrolyte to pass through the first communicating hole 221, nor does the conductive portion 72 need to be smaller to allow the electrolyte to pass through the first communicating hole 221. The first communicating hole 221 only needs to be slightly larger than the conductive portion 72 to allow the conductive portion 72 to pass through. This can alleviate the problem of impurities and the like falling into the accommodating cavity 1A through the gap between the conductive portion 72 and the first communicating hole 221. It can also alleviate the problem of localized weakness in the pole body 2 caused by the oversized first communicating hole 221. The conductive portion 72 can also be relatively larger, which is beneficial for improving the current flow efficiency. Furthermore, since the electrolyte is not affected by the conductive portion 72 when passing through the second communicating hole 222, the injection efficiency can be improved, and the electrolyte is less likely to cause contamination and corrosion on the conductive portion 72.

[0137] For example, in Example 1 of the present application, there is at least one connecting hole 22, and each connecting hole 22 is penetrated by a conductive portion 72, so each connecting hole 22 is a first connecting hole 221. At this time, at least one first connecting hole 221 constitutes a liquid hole 23. After the electrolyte is injected into the containing tank 211, it flows into the containing cavity 1A from the first connecting hole 221 penetrated by the conductive portion 72.

[0138] For example, in Example 2 of the present application, there are at least two connecting holes 22, at least one connecting hole 22 is a first connecting hole 221 having a conductive portion 72 passed through it, and at least one connecting hole 22 is a second connecting hole 222 not having a conductive portion 72 passed through it. At this time, the first connecting hole 221 and the second connecting hole 222 both constitute liquid holes 23. After the electrolyte is injected into the containing tank 211, a part of it flows into the containing cavity 1A from the first connecting hole 221 having a conductive portion 72 passed through it, and the rest of it flows into the containing cavity 1A from the second connecting hole 222 not having a conductive portion 72 passed through it.

[0139] For example, in Example 3 of the present application, there are at least two connecting holes 22, at least one connecting hole 22 is a first connecting hole 221 having a conductive portion 72 passing through it, and at least one connecting hole 22 is a second connecting hole 222 not having a conductive portion 72 passing through it. After the first connecting hole 221 passes through the conductive portion 72, it is blocked and cannot pass liquid. At this time, only the second connecting hole 222 constitutes the liquid hole 23. After the electrolyte is injected into the containing tank 211, it flows into the containing cavity 1A from the second connecting hole 222 not having a conductive portion 72 passing through it.

[0140] In some embodiments, referring to Figures 12 and 13 , the pole body 2 is formed into an elongated structure, and the communication hole 22 (i.e., the first communication hole 221) through which the conductive portion 72 is disposed is formed as an elongated hole, with a length greater than a width and extending from one end of the pole body 2 to the other end. This allows full utilization of the space in the pole body 2, maximizing the length of the first communication hole 221. This allows the first communication hole 221 to pass through a larger conductive portion 72, thereby facilitating an increase in the size of the conductive portion 72 and improving current flow efficiency. When the first communication hole 221 serves as the liquid passage 23, increasing the length of the first communication hole 221 also improves liquid injection efficiency.

[0141] In some embodiments, when the connecting hole 22 through which the conductive part 72 is passed is the first connecting hole 221, there are multiple first connecting holes 221 and conductive parts 72, and each first connecting hole 221 is passed through by at least one conductive part 72. At this time, at least two connecting holes 22 are respectively passed through by the conductive part 72, thereby improving the problem that the size of a single first connecting hole 221 is large, resulting in local weak strength of the pole body 2. Moreover, if the first connecting hole 221 is used as a liquid hole 23, increasing the number of the first connecting holes 221 is also beneficial to improving the injection efficiency.

[0142] For example, when the first communication holes 221 are formed as elongated holes with a length greater than width and a length extending from one end of the pole body 2 to the other end, multiple first communication holes 221 can be spaced apart along the width of the pole body 2. This allows for more efficient use of the space on the pole body 2 and alleviates the problem of a single large first communication hole 221 causing localized weakness in the pole body 2. Furthermore, if the first communication holes 221 serve as liquid passage holes 23, increasing the number of first communication holes 221 can also improve liquid injection efficiency.

[0143] In some embodiments, referring to FIG. 13 , when the pole body 2 has both a first communication hole 221 and a second communication hole 222, if the first communication hole 221 is formed as an elongated hole with a length greater than a width and a length extending from one end of the pole body 2 to the other end, the second communication hole 222 can be provided at at least one of the two ends of the length of the first communication hole 221. This allows for full utilization of space, maximizes the size of the second communication hole 222 while improving the structural strength of the pole body 2, and improves liquid injection efficiency. Furthermore, providing a second communication hole 222 at both ends of the length of the first communication hole 221 can further improve liquid injection efficiency, reduce the size of each second communication hole 222, and alleviate the problem of localized weakness in the pole body 2.

[0144] Of course, in the embodiment of the present application, the shape of the first connecting hole 221 and the relative positional relationship between the first connecting hole 221 and the second connecting hole 222 are not limited to the above description and can be adjusted according to actual conditions.

[0145] Of course, the present application is not limited to this. The liquid injection port 1029 may not be set on the pole structure 1022. For example, the liquid injection port 1029 may also be directly set on the shell 1, or set on a pressure relief structure installed on the shell 1, etc., thereby achieving flexible design of the position of the liquid injection port 1029.

[0146] In some embodiments of the present application, as shown in FIG10 , the housing 1 includes a first housing wall 11 , and the liquid injection port 1029 is directly or indirectly provided on the first housing wall 11 . Specifically, as shown in FIG10 , the first housing wall 11 is integrally formed with at least one second housing wall 12 , and the second housing wall 12 extends toward one side in the thickness direction of the first housing wall 11 . Alternatively, the first housing wall 11 may be configured as an integrally formed cover plate. Thus, the position of the liquid injection port 1029 can be flexibly designed, thereby increasing the scope of application of the battery cell 102 of the embodiments of the present application.

[0147] It is worth noting that the second shell wall 12 can extend from an edge of the first shell wall 11. When the first shell wall 11 is rectangular, at least one of the four edges of the first shell wall 11 can extend from the second shell wall 12. For example, only one edge of the first shell wall 11 extends from the second shell wall 12. Alternatively, only two edges of the first shell wall 11 can extend from the second shell wall 12. Alternatively, three edges of the first shell wall 11 can extend from the second shell wall 12. Alternatively, all four edges of the first shell wall 11 can extend from the second shell wall 12. For example, when the housing 1 is a rectangular shell, any wall surface of the rectangular shell can serve as the first shell wall 11.

[0148] For example, the shell 1 may include a shell body and a cover plate, the shell body defines a space open on one side, and the cover plate is arranged on the open side of the shell body to form a accommodating chamber 1A between the shell body and the cover plate. At this time, the wall surface of the shell body opposite to the cover plate is the first shell wall 11, and the wall surface of the shell body connected between the first shell wall 11 and the cover plate is the second shell wall 12, or, the wall surface of the shell body opposite to the cover plate is the second shell wall 12, and the wall surface of the shell body connected between the second shell wall 12 and the cover plate is the first shell wall 11, or, the cover plate is the first shell wall 11, either way.

[0149] According to some embodiments of the present application, in combination with Figures 2 and 14, the present application also provides a battery 100, including a busbar component 103 and a battery cell 102 of any of the above-mentioned solutions, wherein the battery cells 102 are multiple and at least two are electrically connected through the busbar component 103. In this way, multiple battery cells 102 can be connected in series and / or in parallel. The manufacturing efficiency of the battery 100 according to the embodiment of the present application can be improved. It is worth noting that the battery 100 according to the embodiment of the present application may include a case 101 or may not include the case 101.

[0150] For example, when multiple battery cells 102 are connected in series, the anode pole cover 3 of one battery cell 102 is connected to the cathode pole cover 3 of the next battery cell 102 through a busbar component 103, and at the same time, the cathode pole cover 3 of the battery cell 102 is connected to the anode pole cover 3 of the previous battery cell 102 through another busbar component 103.

[0151] The present application also provides an electrical device, including the battery 100 of any of the above solutions. According to some embodiments of the present application, the present application also provides an electrical device, including the battery 100 of any of the above solutions, for providing power to the electrical device. The electrical device can be any of the aforementioned devices or systems employing the battery 100.

[0152] A specific embodiment according to the present application is described below.

[0153] The battery cell 102 includes a shell 1, a pole body 2, a pole cover 3 and a cell assembly 7. The shell 1 defines a accommodating chamber 1A. The pole body 2 is arranged on the shell 1. A accommodating groove 211 and a connecting hole 22 are formed on the pole body 2. The notch of the accommodating groove 211 is open in a direction away from the accommodating chamber 1A. The connecting hole 22 connects the first accommodating groove 211 and the accommodating chamber 1A. There are one or more connecting holes 22 and at least one connecting hole 22 serves as a liquid passage 23. The pole cover 3 is a non-porous cover and is covered on the pole body 2 and is used to seal the notch of the accommodating groove 211.

[0154] The battery cell assembly 7 includes an active material coating portion 71 and a conductive portion 72. The active material coating portion 71 is accommodated in the accommodating cavity 1A. The conductive portion 72 connects the active material coating portion 71 and the pole body 2. The conductive portion 72 is passed through at least one connecting hole 22 to be at least partially accommodated in the first accommodating groove 211. The portion of the conductive portion 72 located in the first accommodating groove 211 is welded to the pole body 2.

[0155] When manufacturing the battery cell 102, the conductive part 72 is first passed through the connecting hole 22 on the pole body 2 to achieve welding between the conductive part 72 and the pole body 2. Then, the electrolyte is injected into the receiving tank 211 using the injection nozzle 9. The electrolyte injected into the receiving tank 211 enters the shell 1 through the liquid hole 23. After the injection is completed, the pole cover 3 is sealed and welded to the pole body 2 to achieve a tight seal.

[0156] The injection nozzle 9 includes a second constant cross-section section 95, an expansion section 92, a first constant cross-section section 94 and a tapered section 93, which are sequentially arranged along the direction from the inlet end 9a of the injection nozzle 9 to the outlet end 9b of the injection nozzle 9. The expansion section 92 is formed into a gradually expanding shape in which the flow area gradually increases along the direction from the inlet end 9a to the outlet end 9b. The flow area of ​​the tapered section 93 gradually decreases along the direction from the inlet end 9a to the outlet end 9b, and the flow area at the minimum cross-section end of the tapered section 93 is larger than the flow area at the minimum cross-section end of the expansion section 92, and the axial length L3 of the tapered section 93 is smaller than the axial length L2 of the expansion section 92, and the outer wall of the tapered section 93 is a smooth curved surface.

[0157] The flow area of ​​the first equal cross-section section 94 is equal to the flow area of ​​the maximum cross-section end of the tapered section 93 and the flow area of ​​the maximum cross-section end of the amplification section 92, respectively, and the axial length L4 of the first equal cross-section section 94 is greater than the axial length L3 of the tapered section 93. The flow area of ​​the second equal cross-section section 95 is equal to the flow area of ​​the minimum cross-section end of the amplification section 92. The minimum cross-section end of the tapered section 93 constitutes the outlet end 9b of the injection nozzle 9, and the end of the second equal cross-section section 95 away from the amplification section 92 constitutes the inlet end 9a of the injection nozzle 9. The flow area of ​​the inlet end 9a of the injection nozzle 9 is smaller than the flow area of ​​the outlet end 9b of the injection nozzle 9. The outlet end 9b of the injection nozzle 9 is formed into a long strip shape, and the cross-sectional shape of the amplification section 92 is consistent with the shape of the outlet end 9b of the injection nozzle 9.

[0158] For example, when the injection nozzle 9 is arranged with the upper end as the inlet end 9a and the lower end as the outlet end 9b, the cross-section of the second uniform cross-section section 95 is circular with a uniform diameter from top to bottom, the cross-section of the expansion section 92 is oblong with a cross-sectional area gradually increasing from top to bottom, the cross-section of the first uniform cross-section section 94 is oblong with a uniform cross-sectional area from top to bottom, and the cross-sectional area of ​​the tapered section 93 is oblong with a cross-sectional area gradually decreasing from top to bottom. The injection nozzle 9 can be made of corrosion-resistant or metal material.

[0159] In the related art, during the injection process of a battery cell, the injection efficiency is low due to the small outlet end of the injection nozzle, and high positive pressure is required to assist the injection. After the injection, the internal retraction of the battery cell causes the electrolyte to spray out. In the embodiment of the present application, however, since the cross-sections of the notch of the receiving tank 211, the expansion section 92, the first uniform cross-section section 94, and the tapered section 93 are all constructed as oblong, during injection, the tapered section 93 is inserted into the notch section of the receiving tank 211. The outlet end 9b of the injection nozzle 9 has a larger area, which is conducive to improving the injection efficiency of the electrolyte. The injection does not require positive pressure, and the electrolyte can effectively reduce the internal pressure of the battery cell 102 during the injection process, thereby reducing the risk of liquid spraying.

[0160] The tapered section 93 is inserted into the notch section of the accommodating groove 211. Since the tapered section 93 is in a closed form and the outer wall is a smooth curved surface, the friction problem caused by the tapered section 93 being inserted into the notch section of the accommodating groove 211 can be reduced, and the reliability problem caused by the conductive particles generated by friction entering the battery cell 102 can be reduced, thereby improving the reliability of the battery cell 102.

[0161] In short, the top of the injection nozzle 9 is connected to the electrolyte supply channel of the injection device, and the bottom is directly connected to the injection port 1029 on the battery cell 102. The outlet end 9b of the injection nozzle 9 is oblong, which can effectively increase the injection area and improve the injection efficiency. At the same time, the outlet end 9b of the injection nozzle 9 is set to a closed form, which can fit well with the injection port 1029, which is conducive to reducing the problem of electrolyte overflow during the injection process. The insertion of the injection nozzle 9 into the injection port 1029 can also better prevent the injection nozzle 9 and the injection port 1029 from rubbing against each other, causing the conductive particles to fall, thereby improving the reliability of the battery cell 102.

[0162] It should be noted that, unless there is any conflict, the embodiments and features in the embodiments of this application can be combined with each other.

[0163] The above are merely preferred embodiments of the present application and are not intended to limit the present application. Those skilled in the art will readily appreciate that various modifications and variations are possible. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present application shall be included within the scope of protection of the present application.

Claims

1. A liquid injection nozzle, wherein: The liquid injection nozzle comprises an expansion section, and a flow area of ​​the liquid injection nozzle increases in the expansion section along a direction from an inlet end of the liquid injection nozzle to an outlet end of the liquid injection nozzle.

2. The liquid injection nozzle according to claim 1, wherein: The flow area of ​​the inlet end of the liquid injection nozzle is smaller than the flow area of ​​the outlet end of the liquid injection nozzle.

3. The liquid injection nozzle according to claim 1 or 2, wherein: The expansion section is formed in a gradually expanding shape in which a flow area gradually increases along a direction from the inlet end to the outlet end.

4. The liquid injection nozzle according to any one of claims 1 to 3, wherein: The injection nozzle includes a tapered section, which is arranged on a side of the expansion section away from the inlet end. The flow area of ​​the tapered section gradually decreases along the direction from the inlet end to the outlet end, and the smallest cross-section end of the tapered section constitutes the outlet end.

5. The liquid injection nozzle according to claim 4, wherein: The flow area of ​​the minimum cross-section end of the tapered section is larger than the flow area of ​​the minimum cross-section end of the amplification section, and the axial length of the tapered section is smaller than the axial length of the amplification section.

6. The liquid injection nozzle according to claim 4 or 5, wherein: The injection nozzle includes a first equal cross-sectional section, which is connected between the expansion section and the tapered section, and the flow area of ​​the first equal cross-sectional section is equal to the flow area of ​​the maximum cross-sectional end of the tapered section and the flow area of ​​the maximum cross-sectional end of the expansion section, and the axial length of the first equal cross-sectional section is greater than the axial length of the tapered section.

7. The liquid injection nozzle according to any one of claims 4 to 6, wherein: The outer wall of the tapered section is a smooth curved surface.

8. The liquid injection nozzle according to any one of claims 1 to 7, wherein: The injection nozzle includes a second equal cross-sectional section, which is connected to the side of the amplification section away from the outlet end, and the flow area of ​​the second equal cross-sectional section is equal to the flow area of ​​the minimum cross-sectional end of the amplification section, and the end of the second equal cross-sectional section away from the amplification section constitutes the inlet end.

9. The liquid injection nozzle according to any one of claims 1 to 8, wherein: The outlet end of the liquid injection nozzle is formed in a long strip shape.

10. The liquid injection nozzle according to any one of claims 1 to 9, wherein: The cross-sectional shape of the amplification section is consistent with the shape of the outlet end of the injection nozzle.

11. A liquid injection device, wherein: It comprises a liquid injection nozzle according to any one of claims 1-10.

12. A battery cell, wherein: It comprises a shell component, wherein the shell component has a accommodating cavity, and the shell component has a liquid injection port connected to the accommodating cavity, and the battery cell is injected with liquid using the liquid injection nozzle according to any one of claims 1-11, and the liquid injection nozzle injects liquid into the accommodating cavity through the liquid injection port.

13. The battery cell according to claim 12, wherein: The shape of the liquid injection port matches the shape of the outlet end of the liquid injection nozzle.

14. The battery cell according to claim 12 or 13, wherein: The outlet end of the liquid injection nozzle is suitable for being embedded in the liquid injection port.

15. The battery cell according to any one of claims 12 to 14, wherein: The shell component has a receiving groove with a notch opening toward a direction away from the receiving cavity. The shell component also has a liquid hole connecting the receiving groove and the receiving cavity. The notch of the receiving groove constitutes the liquid injection port.

16. The battery cell according to claim 15, wherein: The cross section of the notch section of the accommodating groove gradually increases in a direction away from the accommodating cavity.

17. The battery cell according to any one of claims 12 to 16, wherein: The shell assembly comprises a shell and a pole structure, the shell defines a receiving cavity, the pole structure is arranged on the shell, and the liquid injection port is arranged on the pole structure.

18. The battery cell according to claim 15 or 16, wherein: The shell assembly includes a shell and a pole structure, the shell defines a accommodating cavity, the pole structure includes a pole body and a pole cover plate, the pole body is installed on the shell, the accommodating groove and the liquid hole are both formed on the pole body, and the pole cover plate is covered on the notch of the accommodating groove.

19. The battery cell according to claim 18, wherein: The pole body is in the shape of an elongated strip, and the receiving groove is formed as an elongated strip groove extending in the length direction from one end of the pole body to the other end of the pole body.

20. The battery cell according to claim 18 or 19, wherein: The battery cell includes a cell assembly, which includes an active material coating portion received in the accommodating cavity, and a conductive portion connected to the active material coating portion. A connecting hole connecting the accommodating groove and the accommodating cavity is formed on the pole body. There are one or more connecting holes and at least one of the connecting holes serves as the liquid passage hole. The conductive portion is passed through at least one of the connecting holes to be at least partially received in the accommodating groove.

21. A battery, wherein: The invention comprises a busbar component and a battery cell according to any one of claims 12 to 20, wherein the battery cells are plural and at least two of the battery cells are electrically connected via the busbar component.

22. An electrical device, wherein: Comprising a battery according to claim 21.

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