Battery cell, method and apparatus for manufacturing the same, battery, and electric device

Abstract

The application relates to a battery monomer, a manufacturing method and manufacturing equipment thereof, a battery and a power utilization device, and belongs to the technical field of battery manufacturing. The application provides a battery monomer which comprises a shell comprising a first wall, an electrode terminal insulatively installed on the first wall, an electrode assembly arranged in the shell, the electrode assembly being provided with a center hole and a first tab, a current collecting member arranged between the first wall and the electrode assembly, the current collecting member comprising a center part and a surrounding part, the center part being used for connecting the electrode terminal, and the surrounding part being used for connecting the first tab, and a flow guide channel arranged on the current collecting member and configured to guide electrolyte in the center hole to diffuse from the center part to the surrounding part. The battery monomer has high liquid injection efficiency, capacity and safety performance. The application further provides a battery and a power utilization device comprising the battery monomer. The application further provides a manufacturing method and manufacturing equipment of the battery monomer.

Description

Technical Field

[0001] This application relates to the field of battery manufacturing technology, and more specifically, to a battery cell and its manufacturing method and equipment, a battery, and an electrical device. Background Technology

[0002] With the continued prosperity of the new energy vehicle market, the power battery industry has rapidly expanded its production capacity and grown stronger. Lithium battery technology has become increasingly sophisticated, placing higher and higher demands on the safety performance, energy density, and industrialization requirements of battery cells.

[0003] During the assembly of battery cells, electrolyte needs to be injected into the cells to wet the electrode components. However, the current electrolyte injection efficiency for battery cells is low, resulting in poor wetting of the electrode components, leading to low battery cell capacity and poor safety performance. Summary of the Invention

[0004] Therefore, this application proposes a battery cell, its manufacturing method and equipment, battery, and electrical device, wherein the electrolyte can more quickly and fully wet the electrode assembly, thereby not only improving the electrolyte injection efficiency of the battery cell, but also improving the battery cell's capacity and safety performance.

[0005] A first aspect of this application provides a battery cell, comprising: a housing including a first wall; electrode terminals insulatedly mounted on the first wall; an electrode assembly disposed within the housing, the electrode assembly having a central hole, and a first tab formed at one end of the electrode assembly facing the first wall; and a current collector disposed between the first wall and the electrode assembly, the current collector comprising a central portion and a peripheral portion, the central portion corresponding to the central hole, the central portion being used to connect the electrode terminals, and the peripheral portion being used to connect the first tab; wherein the current collector is provided with a flow guiding channel configured to guide electrolyte in the central hole to diffuse from the central portion to the peripheral portion.

[0006] When injecting electrolyte into a battery cell, the electrolyte enters the central hole, and the flow channel guides the electrolyte in the central hole to diffuse from the center to the surrounding area, so as to quickly and fully wet the electrode assembly. This not only improves the electrolyte injection efficiency of the battery cell, but also improves the battery cell's capacity and safety performance.

[0007] According to some embodiments of this application, the flow channel is a first through hole, which is located at the edge of the central portion.

[0008] In the above scheme, the first through hole is located at the edge of the center. The electrolyte flows through the first through hole from the side of the current collector near the electrode assembly to the side near the first wall, and then diffuses to the surrounding area, quickly and fully wetting the electrode assembly.

[0009] According to some embodiments of this application, the central portion protrudes from the surrounding portion in the direction of the electrode terminal, the current collector further includes a transition portion surrounding the central portion, the transition portion connecting the central portion and the surrounding portion, and the first through hole is disposed in the transition portion.

[0010] In the above design, the central portion protrudes from the surrounding portion towards the electrode terminals, and together with the transition portion, forms a liquid storage space communicating with the central hole. A first through-hole is formed in the transition portion. After the electrolyte enters the liquid storage space from the central hole, it flows along the opening direction of the first through-hole to the side of the current collector near the first wall. Because the electrolyte continues to diffuse to the surrounding portion along the opening direction of the first through-hole, it can quickly and fully wet the electrode assembly.

[0011] According to some embodiments of this application, the number of the first through holes is multiple, and the multiple first through holes are spaced apart around the central portion.

[0012] In the above scheme, multiple first through holes are spaced apart around the central part, which can guide the electrolyte to diffuse circumferentially around the central part to the surrounding part, so that the electrolyte can quickly and fully wet the electrode assembly.

[0013] According to some embodiments of this application, along the circumference of the central portion, the total length of the plurality of first through holes is greater than or equal to 1 / 2 of the circumference of the transition portion.

[0014] In the above scheme, since the overcurrent area of ​​the transition section is smaller than that of the central and surrounding sections connected to it, the current collector component is melted in time when the internal current of the battery cell is too large, so that the electrode terminal is disconnected from the first tab in time, and the battery cell has better safety performance.

[0015] According to some embodiments of this application, the first through hole is an arc-shaped hole extending circumferentially along the center portion.

[0016] In the above scheme, the first through hole is an arc-shaped hole extending circumferentially along the center, which can increase the opening area of ​​the first through hole, which is conducive to the diffusion of electrolyte, and can also reduce the height of the center protrusion relative to the surrounding part, reduce the thickness of the current collector, and make the battery cell structure compact and have a higher energy density.

[0017] According to some embodiments of this application, a second through hole is provided on the surrounding portion, and the second through hole is further away from the center portion relative to the first through hole.

[0018] In the above scheme, the second through hole is provided in the surrounding part, which can partially expose the gap between two adjacent electrode layers of the electrode assembly. The electrolyte can enter the gap between two adjacent electrode layers of the electrode assembly through the second through hole to quickly and fully wet the electrode assembly.

[0019] According to some embodiments of this application, the number of second through holes is multiple, and the multiple second through holes are spaced apart around the central portion.

[0020] In the above scheme, multiple second through holes are spaced apart around the central part, which can guide the electrolyte to enter the gap between two adjacent electrode layers of the electrode assembly around the central part in a circumferential direction, so as to quickly and fully wet the electrode assembly.

[0021] According to some embodiments of this application, a first groove is provided on the side of the surrounding portion opposite to the electrode assembly, and the first groove is used to connect the first through hole and the second through hole.

[0022] In the above scheme, the first groove is disposed on the side of the surrounding part away from the electrode assembly, and the first groove connects the first through hole and the second through hole, which can guide the electrolyte to flow from the first through hole to the second through hole to enter the interior of the electrode assembly, and can increase the space on the side of the current collector away from the electrode assembly, thereby increasing the diffusion rate of the electrolyte.

[0023] According to some embodiments of this application, the first groove extends radially along the electrode assembly to the outer peripheral surface of the surrounding portion.

[0024] In the above scheme, the first groove extends to the outer peripheral surface of the surrounding part, which can guide excess electrolyte to flow into the gap between the electrode assembly and the housing, so that the electrolyte can quickly fill the interior of the housing and fully wet the electrode assembly.

[0025] According to some embodiments of this application, the battery cell further includes: an insulating member disposed between the current collector and the first wall for insulating and isolating the current collector and the first wall; the insulating member has a second groove on the side facing the current collector, the second groove being used to connect the first through hole and the second through hole.

[0026] In the above scheme, the electrolyte flowing out from the first through hole enters the gap between the insulating component and the current collector. The second groove can guide the electrolyte to flow from the first through hole to the second through hole to enter the interior of the electrode assembly, and can increase the space on the side of the current collector away from the electrode assembly, thereby increasing the diffusion rate of the electrolyte.

[0027] According to some embodiments of this application, the second groove extends radially along the electrode assembly to the outer peripheral surface of the insulator.

[0028] In the above scheme, the second groove extends to the outer peripheral surface of the insulating component, which can guide excess electrolyte to flow into the gap between the electrode assembly and the housing, so that the electrolyte can quickly fill the interior of the housing and fully wet the electrode assembly.

[0029] According to some embodiments of this application, the flow channel is a third groove, which is disposed on the side of the surrounding portion facing the electrode assembly, and the third groove communicates with the central hole.

[0030] In the above scheme, the electrolyte in the central hole enters the gap between the electrode assembly and the current collector, and the third groove can guide the electrolyte to diffuse to the surrounding area, thereby increasing the diffusion rate of the electrolyte.

[0031] According to some embodiments of this application, the third groove extends radially along the electrode assembly to the outer peripheral surface of the surrounding portion.

[0032] In the above scheme, the third groove extends to the outer peripheral surface of the surrounding part, which can guide excess electrolyte to flow into the gap between the electrode assembly and the housing, so that the electrolyte can quickly fill the interior of the housing and fully wet the electrode assembly.

[0033] According to some embodiments of this application, the outer casing further includes a second wall, which is disposed opposite to the first wall along the axial direction of the central hole. The second wall is provided with a liquid injection hole at a position corresponding to the central hole. The battery cell further includes a sealing element for sealing the liquid injection hole.

[0034] In the above scheme, the injection hole and the flow channel are respectively set on both sides of the central hole along the axial direction. The electrolyte enters the central hole through the injection hole, part of the electrolyte enters the electrode assembly from the central hole, and the other part of the electrolyte enters the flow channel. The flow channel guides the electrolyte to further diffuse from the center to the surrounding part, so as to quickly and fully wet the electrode assembly.

[0035] According to some embodiments of this application, a second tab is formed at one end of the electrode assembly facing the second wall, the first tab and the second tab have opposite polarities, and the second tab is electrically connected to the second wall.

[0036] In the above scheme, the first tab of the battery cell is electrically connected to the electrode terminal, and the second tab is electrically connected to the second wall. The battery cell is electrically connected to the outside through the electrode terminal and the outer casing, which simplifies the structure of the battery cell.

[0037] According to some embodiments of this application, the housing includes a shell and an end cap. The shell includes a bottom wall and a side wall. The side wall surrounds the bottom wall. One end of the side wall is connected to the bottom wall, and the other end forms an opening. The end cap covers the opening. The first wall is the bottom wall, and the second wall is the end cap.

[0038] In the above scheme, the liquid injection hole is opened in the end cap, the electrode terminal is set in the bottom wall, and the current collector is set between the bottom wall and the electrode assembly. This allows the electrode terminal to be welded to the current collector first, and then the opening is covered by the end cap, which simplifies the assembly process of the battery cell.

[0039] A second aspect of this application provides a battery comprising the battery cell described in the second aspect of this application.

[0040] A third aspect of this application provides an electrical device including the battery described in the third aspect of this application.

[0041] The fourth aspect of this application provides a method for manufacturing a single battery cell, comprising:

[0042] A housing and electrode terminals are provided. The housing includes a bottom wall and a side wall. The side wall surrounds the bottom wall, with one end connected to the bottom wall and the other end forming an opening. The electrode terminals are insulated and mounted on the bottom wall.

[0043] An electrode assembly is provided, the electrode assembly having a central hole, a first tab being formed at one end of the electrode assembly, and a second tab being formed at the other end;

[0044] A flow collecting component is provided, the flow collecting component including a central part and a surrounding part, and a flow guiding channel is provided on the flow collecting component;

[0045] An end cap is provided, wherein the end cap is provided with a liquid injection hole;

[0046] Connect the peripheral portion to the first electrode tab, align the central portion with the central hole, place the electrode assembly into the housing, position the current collector between the bottom wall and the electrode assembly, and connect the central portion to the electrode terminal.

[0047] Cover the opening with the end cap and connect it to the second electrode tab, so that the injection hole corresponds to the position of the center hole;

[0048] Electrolyte is injected into the interior of the housing through the injection hole. The electrolyte enters the central hole and diffuses from the center to the surrounding area through the flow channel.

[0049] The fifth aspect of this application provides an apparatus for manufacturing a single battery cell, comprising:

[0050] A first providing device is used to provide a housing and electrode terminals. The housing includes a bottom wall and a side wall. The side wall surrounds the bottom wall. One end of the side wall is connected to the bottom wall, and the other end forms an opening. The electrode terminals are insulated and mounted on the bottom wall.

[0051] A second providing device is used to provide an electrode assembly having a central hole, a first tab being formed at one end of the electrode assembly, and a second tab being formed at the other end;

[0052] A third providing device is used to provide a flow collecting component, the flow collecting component including a central part and a peripheral part, and a flow guiding channel is provided on the flow collecting component;

[0053] The fourth providing device is used to provide an end cap, wherein the end cap is provided with a liquid injection hole;

[0054] The first assembly module is used to connect the peripheral portion to the first tab, align the central portion with the central hole, place the electrode assembly into the housing, position the current collector between the bottom wall and the electrode assembly, connect the central portion to the electrode terminal, cover the opening with the end cap and connect it to the second tab, and align the injection hole with the central hole.

[0055] The second assembly module is used to inject electrolyte into the interior of the housing through the injection hole. The electrolyte enters the central hole and diffuses from the center to the surrounding area through the flow channel.

[0056] Additional aspects and advantages of this application will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of this application. Attached Figure Description

[0057] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0058] Figure 1 The diagram shown is a simplified schematic of a vehicle according to one embodiment of this application;

[0059] Figure 2 What is shown is Figure 1 A schematic diagram of the battery structure in a Chinese vehicle;

[0060] Figure 3The diagram shown is an exploded view of a battery cell according to some embodiments of this application;

[0061] Figure 4 What is shown is Figure 3 Cross-sectional view of a single battery cell;

[0062] Figure 5 The diagram shown is a structural schematic of a first type of current collector for a battery cell according to some embodiments of this application;

[0063] Figure 6 What is shown is Figure 5 A schematic diagram of the structure of the flow guide channel and the central hole of the flow collection component;

[0064] Figure 7 The diagram shown is a structural schematic of a second type of current collector for a battery cell according to some embodiments of this application;

[0065] Figure 8 What is shown is Figure 7 A schematic diagram of the structure of the flow guide channel and the central hole of the flow collection component;

[0066] Figure 9 The diagram shown is a structural schematic of a third type of current collector in a battery cell according to some embodiments of this application;

[0067] Figure 10 What is shown is Figure 9 A schematic diagram of the structure of the flow guide channel and the central hole of the flow collection component;

[0068] Figure 11 The diagram shown is a structural schematic of a third type of current collector in a battery cell according to some embodiments of this application;

[0069] Figure 12 What is shown is Figure 11 A schematic diagram of the structure of the flow guide channel and the central hole of the flow collection component;

[0070] Figure 13 The diagram shown is a structural schematic of the insulating component in a battery cell according to some embodiments of this application;

[0071] Figure 14 What is shown is Figure 13 A schematic diagram of the structure of the guide channel between the middle insulating component and the current collecting component;

[0072] Figure 15 The diagram shown is a structural schematic of a fourth type of current collector in a battery cell according to some embodiments of this application;

[0073] Figure 16 What is shown is Figure 15A schematic diagram of the structure of the flow guide channel and the central hole of the flow collection component;

[0074] Figure 17 The diagram shown is a schematic representation of a method for manufacturing a battery cell according to some embodiments of this application;

[0075] Figure 18 The diagram shown is a schematic diagram of a battery cell manufacturing apparatus according to some embodiments of this application;

[0076] The above figures are not provided to scale.

[0077] Icons: 1000 - Vehicle; 100 - Battery; 10 - Battery cell; 11 - Casing; 111 - Shell; 1111 - Bottom wall; 1112 - Side wall; 112 - End cap; 1121 - Injection hole; 113 - Opening; 12 - Electrode assembly; 121 - Body; 1211 - Center hole; 1212 - First end; 1213 - Second end; 122 - First tab; 123 - Second tab; 13 - Electrode terminal; 14 - Current collector; 141 - Center; 142 - Peripheral; 1421 - Second through hole; 1422 - First groove; 1423 - Third groove; 1424 - First outer peripheral surface; 14 3-Transition section; 1431-First through hole; 144-First surface; 145-Second surface; 146-Liquid storage space; 15-Seal; 16-Insulator; 161-Third surface; 1611-Second groove; 162-Fourth surface; 163-Second outer peripheral surface; 20-Box; 21-First box; 22-Second box; 200-Controller; 300-Motor; 2000-Manufacturing equipment; 2100-First supply device; 2200-Second supply device; 2300-Third supply device; 2400-Fourth supply device; 2500-First assembly module; 2600-Second assembly module. Detailed Implementation

[0078] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0079] Unless otherwise defined, all technical and scientific terms used in this application have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the terminology used in the description of this application is for the purpose of describing particular embodiments only and is not intended to limit the application; the terms "comprising" and "having," and any variations thereof, in the description, claims, and accompanying drawings of this application are intended to cover non-exclusive inclusion. The terms "first," "second," etc., in the description, claims, or accompanying drawings of this application are used to distinguish different objects, not to describe a specific order or hierarchy.

[0080] In this application, the term "embodiment" means that a specific feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a mutually exclusive, independent, or alternative embodiment. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described in this application can be combined with other embodiments.

[0081] In the description of this application, it should be noted that unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "attachment" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0082] In this application, "multiple" means two or more (including two).

[0083] In this application, the battery cell 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 are not limited to these. The battery cell may be cylindrical, flat, cuboid, or other shapes, etc., and the embodiments of this application are not limited to these. Battery cells are generally divided into three types according to their packaging method: cylindrical battery cells, prismatic battery cells, and pouch battery cells.

[0084] The battery mentioned in the embodiments of this application refers to a single physical module comprising one or more battery cells to provide higher voltage and capacity. For example, the battery mentioned in this application may include a battery module or a battery pack. A battery generally includes a housing for encapsulating one or more battery cells, which prevents liquids or other foreign matter from affecting the charging or discharging of the battery cells.

[0085] A single battery cell includes an electrode assembly and an electrolyte. The electrode assembly consists of a positive electrode, a negative electrode, and a separator. The battery cell primarily functions by the movement of metal ions between the positive and negative electrodes. The positive electrode includes a positive current collector and a positive active material layer. The positive active material layer is coated on the surface of the positive current collector, and the uncoated positive current collector protrudes beyond the coated one, serving as the positive electrode tab. Taking a lithium-ion battery as an example, the positive current collector can be made of aluminum, and the positive active material can be lithium cobalt oxide, lithium iron phosphate, ternary lithium, or lithium manganese oxide, etc. The negative electrode includes a negative current collector and a negative active material layer. The negative active material layer is coated on the surface of the negative current collector, and the uncoated negative current collector protrudes beyond the coated one, serving as the negative electrode tab. The negative electrode current collector can be made of copper, and the negative electrode active material can be carbon or silicon, etc. To ensure that a large current can pass through without melting, there are multiple positive electrode tabs stacked together, and there are multiple negative electrode tabs stacked together. The separator can be made of PP (polypropylene) or PE (polyethylene), etc. In addition, the electrode assembly can be a wound structure or a stacked structure, and the embodiments of this application are not limited to these.

[0086] The battery cell also includes a current collector, which is used to electrically connect the tabs and electrode terminals of the battery cell to deliver electrical energy from the electrode assembly to the electrode terminals, and then to the outside of the battery cell via the electrode terminals. Multiple battery cells are electrically connected through a current collector to realize series, parallel or mixed connection of multiple battery cells.

[0087] In related technologies, when injecting electrolyte into a battery cell, the electrolyte has difficulty spreading after entering the casing. This not only results in a long injection time and low injection efficiency, but also prevents the electrolyte from fully wetting the electrode components. Consequently, the electrolyte does not fully wet the electrode components, making it easy for lithium plating to occur in the battery cell during charging and discharging, and the battery capacity is also affected.

[0088] The inventors discovered that the internal structure of a battery cell is typically quite compact, with tight contact between the electrode assembly and current collector, between the current collector and the casing, and between the electrode assembly and the casing. This reduces the volume of the battery cell and increases its energy density. However, existing battery cells lack internal channels to guide the rapid diffusion of the electrolyte. After entering the casing, the electrolyte diffuses through the gaps between the two tightly contacting components, resulting in slow and uneven diffusion. This leads to low electrolyte injection efficiency and poor wetting of the electrode assembly.

[0089] Based on the above ideas, this application proposes a new technical solution in which the electrolyte can wet the electrode assembly more quickly and fully, thereby not only improving the electrolyte injection efficiency of the battery cell, but also improving the battery cell's capacity and safety performance.

[0090] It is understood that the battery cells described in the embodiments of this application can directly supply power to electrical devices, or they can be connected in parallel or series to form a battery to supply power to various electrical devices in the form of a battery.

[0091] It is understood that the electrical devices using battery cells, battery modules, or batteries described in the embodiments of this application can take many forms, such as mobile phones, portable devices, laptops, electric vehicles, electric cars, ships, spacecraft, electric toys, and power tools. For example, spacecraft include airplanes, rockets, space shuttles, and spacecraft. Electric toys include stationary or mobile electric toys, such as game consoles, electric car toys, electric ship toys, and electric airplane toys. Power tools include metal cutting power tools, grinding power tools, assembly power tools, and railway power tools, such as electric drills, electric grinders, electric wrenches, electric screwdrivers, electric hammers, impact drills, concrete vibrators, and electric planers.

[0092] The battery cells and batteries described in the embodiments of this application are not limited to the electrical devices described above, but can also be applied to all electrical devices that use battery cells and batteries. However, for the sake of brevity, the following embodiments are all illustrated using electric vehicles as an example.

[0093] Figure 1 The diagram shown is a simplified schematic of a vehicle according to one embodiment of this application. Figure 2 What is shown is Figure 1 A schematic diagram of the battery structure in a Chinese vehicle.

[0094] like Figure 1 As shown, the vehicle 1000 is equipped with a battery 100, a controller 200, and a motor 300. For example, the battery 100 can be installed at the bottom, front, or rear of the vehicle 1000. The vehicle 1000 can be a gasoline-powered vehicle, a natural gas-powered vehicle, or a new energy vehicle. New energy vehicles can be pure electric vehicles, hybrid electric vehicles, or range-extended electric vehicles, etc.

[0095] In some embodiments of this application, the battery 100 can be used to power the vehicle 1000; for example, the battery 100 can serve as the operating power source for the vehicle 1000. The controller 200 is used to control the power supply provided by the battery 100 to the motor 300, for example, to meet the power requirements of the vehicle 100 during startup, navigation, and driving.

[0096] In other embodiments, the battery 100 can not only serve as the operating power source for the vehicle 1000, but also as the driving power source for the vehicle 1000, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle.

[0097] In this application, the battery 100 mentioned in the embodiments refers to a single physical module comprising one or more battery cells 10 to provide higher voltage and capacity. Multiple battery cells 10 can be connected in series, parallel, or a combination thereof to directly form the battery 100. A combination thereof means that multiple battery cells 10 are connected in both series and parallel configurations. Alternatively, multiple battery cells 10 can first be connected in series, parallel, or a combination thereof to form a battery 100 module, and then multiple battery 100 modules can be connected in series, parallel, or a combination thereof to form the battery 100.

[0098] like Figure 2 As shown, the battery 100 includes multiple battery cells 10 and a housing 20, with the battery cells 10 placed inside the housing 20. The housing 20 includes a first housing 21 and a second housing 22, which are closed together to form a battery 100 cavity, within which multiple battery 100 modules are placed. The shapes of the first housing 21 and the second housing 22 can be determined based on the combined shape of the multiple battery 100 modules, and both the first housing 21 and the second housing 22 may have an opening. For example, both the first housing 21 and the second housing 22 can be hollow cuboids with only one open side each. The openings of the first housing 21 and the second housing 22 are opposite to each other, and the first housing 21 and the second housing 22 are interlocked to form a housing 20 with a closed cavity. Multiple battery cells 10 are connected in parallel, series, or mixed configurations and placed inside the housing 20 formed by the interlocking of the first housing 21 and the second housing 22.

[0099] Figure 3 The diagram shown is an exploded view of a battery cell according to some embodiments of this application; Figure 4 What is shown is Figure 3 Cross-sectional view of a single battery cell.

[0100] like Figure 3 and Figure 4 As shown, the battery cell 10 includes a housing 11, an electrode assembly 12, electrode terminals 13, a current collector 14, and a seal 15.

[0101] The housing 11 includes a housing 111 and an end cap 112. The housing 111 includes a bottom wall 1111 and a side wall 1112. The side wall 1112 surrounds the bottom wall 1111. One end of the side wall 1112 is connected to the bottom wall 1111, and the other end forms an opening 113. The end cap 112 covers the opening 113 to enclose the electrode assembly 12 inside the housing 11.

[0102] One of the bottom wall 1111 and the end cap 112 is provided with an electrode lead-out hole, and the electrode terminal 13 is insulated and installed in the electrode lead-out hole. The electrode lead-out hole is provided with a plastic part with a through hole, and the electrode terminal 13 is installed in the through hole to achieve insulated installation in the electrode lead-out hole.

[0103] The housing 111 can be cylindrical, elliptical, or hexahedral. The housing 111 can be made of a metallic material, such as aluminum, aluminum alloy, or nickel-plated steel. The end cap 112 is a plate-like structure, and its size and shape match the opening 113 of the housing 111. The end cap 112 is fixed to the opening 113 of the housing 111, thereby enclosing the electrode assembly 12 and the electrolyte within the receiving cavity of the housing 111. The end cap 112 is made of a metallic material, such as aluminum or steel.

[0104] In some embodiments of this application, the housing 111 is a cylinder, with its axial direction extending along a first axis P and its radial direction extending along a first direction R. The first axis P and the first direction R are perpendicular to each other, and the end cap 112 is a circular plate structure. In other embodiments, the housing 111 may also be a hexahedron, and the end cap 112 may be a square or rectangular plate structure.

[0105] Electrode assembly 12 is disposed within housing 11. Electrode assembly 12 includes a main body 121, a first tab 122, and a second tab 123. The main body 121 includes a positive electrode, a negative electrode, and a separator. The separator is located between the positive and negative electrode to separate them. The first tab 122 and the second tab 123 have opposite polarities. The first tab 122 is connected to electrode terminal 13 via current collector 14, and the second tab 123 is electrically connected to housing 11. Of the first tab 122 and the second tab 123, the first tab 122 is the positive tab, and the second tab 123 is the negative tab. The second tab 123 can be in direct contact with housing 11 or connected to housing 11 via another current collector. The material of the current collector 14 corresponding to the first tab 122 is aluminum, and the material of the current collector corresponding to the second tab 123 is copper, based on the implementation form that "the second tab 123 is connected to the outer casing 11 through another current collector".

[0106] The current collector 14 is used to connect the first tab 122 and the electrode terminal 13. The current collector 14 includes a central portion 141 and a peripheral portion 142. The central portion 141 corresponds to the central hole 1211. The central portion 141 is used to connect the electrode terminal 13, and the peripheral portion 142 is used to connect the first tab 122.

[0107] The thickness direction of the current collecting member 14 extends along the first axis P. The size and shape of the current collecting member 14 can match the size and shape of the housing 111 or not match the size and shape of the housing 111.

[0108] In some embodiments of this application, the housing 111 is cylindrical, and the current collecting member 14 is a circular plate structure with its axis along the first axis P. In other embodiments, the housing 111 may also be hexahedral, and the current collecting member 14 may be a square plate structure with its thickness direction extending along the first axis P.

[0109] like Figure 3 and Figure 4 As shown, the outer casing 11 also has an injection hole 1121, which is used to inject electrolyte into the interior of the outer casing 11. The sealing element 15 is used to seal the injection hole 1121 after the electrolyte injection is completed. The injection hole 1121 can be sealed by a riveting process, forming the sealing element 15 after riveting. The sealing element 15 can also be an elastic element made of rubber, silicone, or other materials, which is inserted into the injection hole 1121 to seal it.

[0110] like Figure 3 and Figure 4 As shown, some embodiments of this application propose a battery cell 10, including a housing 11, an electrode assembly 12, and a current collector 14. The housing 11 includes a first wall, with electrode terminals 13 insulatedly mounted to the first wall. The electrode assembly 12 is disposed within the housing 11, having a central hole 1211. A first tab 122 is formed at the end of the electrode assembly 12 facing the first wall. The current collector 14 is disposed between the first wall and the electrode assembly 12, and includes a central portion 141 and a peripheral portion 142. The central portion 141 corresponds to the central hole 1211, and is used to connect the electrode terminals 13. The peripheral portion 142 is used to connect the first tab 122. A flow channel is provided on the current collector 14, configured to guide the electrolyte in the central hole 1211 to diffuse from the central portion 141 to the peripheral portion 142.

[0111] The electrode assembly 12 is formed by winding, and the central hole 1211 is the winding center of the electrode assembly 12. The central hole 1211 penetrates the main body 121 along the first axis P. Along the extension direction of the first axis P, the end of the central hole 1211 near the first wall is the first end 1212, and the end away from the first wall is the second end 1213.

[0112] The first wall is arranged on the same side as the first tab of the electrode assembly, and the first wall is part of the shell wall of the outer casing. In some embodiments of this application, the first wall is a bottom wall 1111, and the electrode terminal 13 is insulatedly disposed on the bottom wall 1111. In other embodiments, the first wall may also be an end cap 112, and the electrode terminal 13 is insulatedly disposed on the end cap 112.

[0113] The injection hole 1121 can be located on the first wall or on other walls of the outer casing. In some embodiments of this application, along the extension direction of the first axis P, the injection hole 1121 is located on the opposite side of the electrode terminal 13, and the injection hole 1121 corresponds to the second end 1213 of the central hole 1211. The electrolyte flows from the second end 1213 of the central hole 1211 to the first end 1212, and then diffuses into the periphery 142 of the current collecting member 14 through the flow guiding channel. In other embodiments, the injection hole 1121 can also be located on the same side as the electrode terminal 13, and the injection hole 1121 corresponds to the first end 1212 of the central hole 1211. The electrolyte enters the central hole 1211 from the first end 1212 of the central hole 1211, and then diffuses into the periphery 142 of the current collecting member 14 through the flow guiding channel.

[0114] The current collector 14 can have various embodiments. The central portion 141 can be a circular plate structure or a square plate structure; the peripheral portion 142 can be a closed annular structure arranged circumferentially around the central portion 141, or it can be an open annular structure arranged circumferentially around the central portion 141. The edge of the central portion 141 can be directly connected to the peripheral portion 142, and the surfaces of the central portion 141 and the peripheral portion 142 are flush; the central portion 141 can also protrude from the peripheral portion 142 toward the electrode terminal 13. The central axis of the central portion 141 and the central axis of the peripheral portion 142 can be coincident, for example, the central portion 141 is a disc structure, and the peripheral portion 142 is an annular structure arranged circumferentially around the central axis of the disc structure; the central axis of the central portion 141 and the central axis of the peripheral portion 142 can also be non-coincident, so as to reliably connect with the electrode terminal.

[0115] The central portion 141 corresponds to the central hole 1211, allowing the electrolyte in the central hole 1211 to enter the guiding channel from the first end 1212 and diffuse from the central portion 141 to the surrounding portion 142. The central portion 141 and the central hole 1211 can be coaxially or non-coaxially arranged. In some embodiments of this application, the central axis of the central portion 141 coincides with the axis of the central hole 1211, that is, the central axis of the central portion 141 is also the first axis P; in other embodiments, the central axis of the central portion 141 may also be parallel to or inclined to the first axis P.

[0116] The flow channel is used to guide the electrolyte to diffuse from the central hole 1211 to the surrounding portion 142. The flow channel can have various implementations. The flow channel can be a through hole provided at the edge of the central portion 141, through which the electrolyte flows from the first through hole 1431 to the side of the current collector 14 away from the electrode assembly 12 and diffuses into the surrounding portion 142. Alternatively, the flow channel can be a groove provided on the side of the surrounding portion 142 facing the electrode assembly 12, through which the electrolyte enters between the current collector 14 and the electrode assembly 12 and diffuses into the surrounding portion 142.

[0117] One end of the flow channel is connected to the central hole 1211, and the other end can extend to the surrounding part 142 or to the edge of the flow collecting member 14; further, the other end of the flow channel can extend along the first direction R to the edge of the flow collecting member 14, or it can spiral around the first axis P to the edge of the flow collecting member 14.

[0118] There can be one flow channel, through which all the electrolyte in the central hole 1211 diffuses from the center 141 to the surrounding part 142; or there can be multiple flow channels, which are circumferentially distributed around the first axis P. The electrolyte in the central hole 1211 enters multiple flow channels, and the multiple flow channels together guide the electrolyte to diffuse from the center 141 to the surrounding part 142.

[0119] When the battery cell 10 is injected with electrolyte, the electrolyte enters the central hole 1211. The flow channel guides the electrolyte in the central hole 1211 to diffuse from the center 141 to the surrounding part 142, so as to quickly and fully wet the electrode assembly 12. This not only improves the electrolyte injection efficiency and assembly efficiency of the battery cell 10, but also improves the stability of the capacitance of the battery cell 10.

[0120] like Figure 3 and Figure 4 As shown, in some embodiments of this application, the outer casing 11 further includes a second wall, which is disposed opposite to the first wall along the axial direction of the central hole 1211. The second wall is provided with a liquid injection hole 1121 at the position corresponding to the central hole 1211. The battery cell 10 further includes a sealing member 15 for sealing the liquid injection hole 1121.

[0121] The central hole 1211 extends along the first axis P. A second wall and a first wall are respectively disposed on opposite sides of the central hole 1211 along the first axis P. The second wall is located at the second end 1213 of the central hole 1211, thus achieving a cross-sectional arrangement of the injection hole 1121 and the flow guiding channel of the flow collecting member 14. Based on the aforementioned embodiment where "the first wall is the bottom wall 1111," the second wall is an end cap 112, and the injection hole 1121 is disposed on the end cap 112. Based on the aforementioned embodiment where "the first wall is the end cap 112," the second wall is the bottom wall 1111, and the injection hole 1121 is disposed on the bottom wall 1111.

[0122] With the above-described structure, the injection hole 1121 and the flow channel are respectively located on both sides of the central hole 1211 along the axial direction. The electrolyte enters the central hole 1211 through the injection hole 1121. A portion of the electrolyte enters the electrode assembly 12 from the central hole 1211, and another portion of the electrolyte enters the flow channel. The flow channel guides the electrolyte to further diffuse from the central part 141 to the surrounding part 142, so as to quickly and fully wet the electrode assembly 12.

[0123] like Figure 3 and Figure 4 As shown, in some embodiments of this application, a second tab 123 is formed at the end of the electrode assembly 12 facing the second wall. The first tab 122 and the second tab 123 have opposite polarities, and the second tab 123 is electrically connected to the second wall.

[0124] Based on the aforementioned implementation of "the first wall is the bottom wall 1111 and the second wall is the end cap 112", the second electrode 123 is connected to the end cap 112 through another current collector 14. The current collector 14, which is provided with a current guide channel, is disposed between the bottom wall 1111 and the electrode assembly 12. The central part 141 of the current collector 14 is connected to the electrode terminal 13, and the peripheral part 142 is connected to the first electrode 122.

[0125] Based on the aforementioned implementation of "the first wall is the end cap 112 and the second wall is the bottom wall 1111", the second electrode 123 is connected to the bottom wall 1111 through another current collector 14. The current collector 14, which is provided with a current guiding channel, is disposed between the end cap 112 and the electrode assembly 12. The central part 141 of the current collector 14 is connected to the electrode terminal 13, and the peripheral part 142 is connected to the first electrode 122.

[0126] With the above structure, the first tab 122 of the battery cell 10 is electrically connected to the electrode terminal 13, the second tab 123 is electrically connected to the second wall, and the outer casing 11 serves as the negative electrode of the battery cell 10 and is electrically connected to the outside, thus simplifying the structure of the battery cell 10.

[0127] like Figure 3 and Figure 4 As shown, in some embodiments of this application, the outer casing 11 includes a housing 111 and an end cap 112. The housing 111 includes a bottom wall 1111 and a side wall 1112. The side wall 1112 surrounds the bottom wall 1111. One end of the side wall 1112 is connected to the bottom wall 1111, and the other end forms an opening 113. The end cap 112 covers the opening 113. The first wall is the bottom wall 1111, and the second wall is the end cap 112.

[0128] With the above-described structure, the injection hole 1121 is opened on the end cap 112, which is easy to manufacture and form; the electrode terminal 13 is disposed on the bottom wall 1111, and the current collector 14 is disposed between the bottom wall 1111 and the electrode assembly 12, which allows the electrode terminal 13 to be welded to the current collector 14 first, and then the end cap 112 to cover the opening 113, simplifying the assembly process of the battery cell 10.

[0129] Figure 5 The diagram shown is a structural schematic of a first type of current collector for a battery cell according to some embodiments of this application; Figure 6 What is shown is Figure 5 A schematic diagram of the flow guiding channel and the central hole of the flow collecting component.

[0130] like Figure 5 and Figure 6 As shown, in some embodiments of this application, the flow channel is a first through hole 1431, which is located at the edge of the central portion 141.

[0131] The "edge of the central portion 141" can be a transition structure between the central portion 141 and the surrounding portion 142, or it can be the part of the surrounding portion 142 that is close to the central portion 141.

[0132] The first through hole 1431 penetrates the current collector 14 along the thickness direction of the current collector 14 to guide the electrolyte into the side of the current collector 14 away from the electrode assembly 12 and further diffuse to the surrounding part 142.

[0133] like Figure 5 and Figure 6 As shown, in some embodiments of this application, the current collecting member 14 is a flat plate structure with a flat surface, the central part 141 is directly connected to the surrounding part 142, the surfaces of the central part 141 and the surrounding part 142 are flat on a plane perpendicular to the first axis P, and the axial direction of the first through hole 1431 is parallel to the first axis P.

[0134] In other embodiments, the current collecting member 14 may also be a flat plate structure with an uneven surface. On a plane perpendicular to the first axis P, the central portion 141 protrudes from the surrounding portion 142, the transition portion 143 connects the central portion 141 and the surrounding portion 142, and the axial direction of the first through hole 1431 is parallel to the first direction R.

[0135] One first through-hole 1431 can be provided, through which all the electrolyte in the central hole 1211 diffuses from the center 141 to the surrounding area 142. Alternatively, multiple first through-holes 1431 can be provided, circumferentially distributed around the first axis P. The electrolyte in the central hole 1211 enters multiple first through-holes 1431, and the multiple first through-holes 1431 jointly guide the electrolyte to diffuse from the center 141 to the surrounding area 142. The first through-hole 1431 can be a circular hole, or an elliptical hole, a square hole, a triangular hole, or an arc-shaped hole, etc.

[0136] With the above-described structure, the first through hole 1431 is located at the edge of the central part 141. The electrolyte flows through the first through hole 1431 from the side of the current collector 14 near the electrode assembly 12 to the side near the first wall, and then diffuses to the surrounding part 142, quickly and fully wetting the electrode assembly 12.

[0137] Figure 7The diagram shown is a structural schematic of a second type of current collector for a battery cell according to some embodiments of this application; Figure 8 What is shown is Figure 7 A schematic diagram of the flow guiding channel and the central hole of the flow collecting component.

[0138] like Figure 7 and Figure 8 As shown, in some embodiments of this application, the central portion 141 protrudes from the surrounding portion 142 in the direction of the electrode terminal 13. The current collector 14 also includes a transition portion 143, which surrounds the central portion 141 and connects the central portion 141 and the surrounding portion 142. A first through hole 1431 is provided in the transition portion 143.

[0139] Along the extension direction of the first axis P, the central portion 141 protrudes from the peripheral portion 142 toward the electrode terminal 13 and is connected to the electrode terminal 13. The transition portion 143 connects the central portion 141 and the peripheral portion 142, which not only electrically connects the central portion 141 and the peripheral portion 142, but also facilitates the provision of a first through hole 1431 in the transition portion 143.

[0140] Along the extension direction of the first axis P, the first through hole 1431 can be provided in the middle of the transition portion 143, or it can be provided on the side of the transition portion 143 near the center portion 141 or near the peripheral portion 142. The first through hole 1431 can be provided entirely in the transition portion 143, or it can extend from the transition portion 143 to the center portion 141 or the peripheral portion 142.

[0141] There are several ways to form the central portion 141 that protrudes toward the electrode terminal 13. The central portion 141 can be formed by stamping, or the central portion 141 and the surrounding portion 142 can be provided separately and then welded together.

[0142] The central portion 141 and the transition portion 143 together enclose a liquid storage space 146 communicating with the first end 1212 of the central hole 1211. The first through hole 1431 penetrates the transition portion 143 along its thickness direction to guide the electrolyte from the liquid storage space 146 to the side of the current collector 14 opposite to the electrode assembly 12. The thickness direction of the transition portion 143 can extend along the first direction R or along other directions inclined to the first axis P.

[0143] With the above-described structure, the central portion 141 protrudes from the surrounding portion 142 toward the electrode terminal 13, and together with the transition portion 143, forms a liquid storage space 146 communicating with the central hole 1211. The first through hole 1431 is opened in the transition portion 143. After the electrolyte enters the liquid storage space 146 along the axial direction of the central hole 1211, it flows along the opening direction of the first through hole 1431 to the side of the current collector 14 near the first wall. Since the electrolyte continues to diffuse to the surrounding portion 142 along the opening direction of the first through hole 1431, it can quickly and fully wet the electrode assembly 12.

[0144] like Figure 7 and Figure 8 As shown, in some embodiments of this application, there are multiple first through holes 1431, and the multiple first through holes 1431 are arranged at intervals around the central portion 141.

[0145] Specifically, the transition portion 143 is disposed around the first axis P, and the radial direction of the transition portion 143 extends along the first direction R, and the axes of the plurality of first through holes 1431 are located on the same plane perpendicular to the first axis P.

[0146] like Figure 7 As shown, in some embodiments of this application, the multiple first through holes 1431 have the same shape and opening size, so that the liquid output of each first through hole 1431 is the same; the multiple first through holes 1431 are uniformly arranged around the central part 141 in a circumferential manner to guide the electrolyte to diffuse uniformly in a circumferential manner.

[0147] In other embodiments, the shape and opening size of the plurality of first through holes 1431 may also be different, and the plurality of first through holes 1431 may also be arranged non-uniformly around the central part 141. By flexibly setting the opening position and number of the first through holes 1431, the space required by other components inside the battery cell 10 can be avoided and the strength of the current collector 14 can be improved, thus avoiding the current collector 14 from breaking due to too many openings in the transition part 143.

[0148] The number of first through holes 1431 can be two to six, which can both improve the diffusion rate of electrolyte and ensure the strength of current collector 14.

[0149] For example, such as Figure 7 As shown, four first through holes 1431 are provided. The four first through holes 1431 are circumferentially spaced around the first axis P in the transition part 143, and two adjacent first through holes 1431 are spaced 90° apart in the direction around the first axis P.

[0150] With the above-described structure, multiple first through holes 1431 are spaced apart around the central portion 141, which can guide the electrolyte to diffuse circumferentially around the central portion 141 to the surrounding portion 142, so that the electrolyte can quickly and fully wet the electrode assembly 12.

[0151] In some embodiments of this application, along the circumference of the central portion 141, the total length of the plurality of first through holes 1431 is greater than or equal to half the circumference of the transition portion 143.

[0152] It is understood that "the total circumferential length of the transition portion 143 along the central portion 141" refers to the circumference of the outer wall 1112 of the transition portion 143 around the first axis P at the midpoint of the portion where the first through hole 1431 is located, along the extension direction of the first axis P. "The total circumferential length of the plurality of first through holes 1431 along the central portion 141" refers to the total length occupied by all the first through holes 1431 at the midpoint of the aforementioned portion where the first through hole 1431 is located.

[0153] Based on the aforementioned embodiment where "one first through hole 1431 is provided", the first through hole 1431 is continuously formed around the first axis P in the transition portion 143, and occupies at least 180° of the circumferential portion of the transition portion 143. The remaining circumferential portion of the transition portion 143 is a connecting region, which is used to connect the central portion 141 and the surrounding portion 142. Based on the aforementioned embodiment where "four first through holes 1431 are evenly spaced around the central portion 141", each first through hole 1431 occupies at least 45° of the circumferential portion of the transition portion 143, and there is a connecting region between two adjacent first through holes 1431, which is used to connect the central portion 141 and the surrounding portion 142.

[0154] With the above-described structure, since the overcurrent area of ​​the transition section 143 is smaller than that of the central section 141 and the surrounding section 142, the current collector 14 can be melted in time when the internal current of the battery cell 10 is too large, so that the electrode terminal 13 is disconnected from the first tab 122, and the battery cell 10 has better safety performance.

[0155] In some embodiments of this application, the first through hole 1431 is an arc-shaped hole extending circumferentially along the center portion 141.

[0156] It is understandable that "the first through hole 1431 is an arc-shaped hole extending circumferentially along the center portion 141" means that on a plane perpendicular to the first axis P, the projection of the first through hole 1431 is an arc-shaped curve curving around the first axis P.

[0157] Based on the aforementioned embodiment of "four first through holes 1431 are evenly spaced around the central portion 141", all four first through holes 1431 are arc-shaped holes extending circumferentially along the central portion 141.

[0158] With the above-described structure, the first through hole 1431 is an arc-shaped hole extending circumferentially along the center portion 141. This can increase the opening area of ​​the first through hole 1431, which is conducive to the diffusion of electrolyte, and reduce the height of the protrusion of the center portion 141 relative to the surrounding portion 142, thereby reducing the thickness of the current collector 14, making the battery cell 10 compact and having a high energy density.

[0159] Figure 9 The diagram shown is a structural schematic of a third type of current collector in a battery cell according to some embodiments of this application; Figure 10 What is shown is Figure 9 A schematic diagram of the flow guiding channel and the central hole of the flow collecting component.

[0160] like Figure 9 and Figure 10 As shown, in some embodiments of this application, a second through hole 1421 is provided on the peripheral portion 142, and the second through hole 1421 is further away from the center portion 141 than the first through hole 1431.

[0161] The second through-hole 1421 extends through the thickness of the surrounding portion 142, and on a plane perpendicular to the first axis P, the projection of the second through-hole 1421 can completely fall inside the projection of the electrode assembly 12. Electrolyte enters between two adjacent electrode layers of the electrode assembly 12 through the second through-hole 1421 to wet the electrode assembly 12. The projection of the second through-hole 1421 can partially fall inside the projection of the electrode assembly 12. A portion of the electrolyte enters between two adjacent electrode layers of the electrode assembly 12 through the second through-hole 1421, while another portion of the electrolyte flows to the edge of the electrode assembly 12 to enter the space between the electrode assembly 12 and the outer casing 11 (see reference). Figure 4 The gap between the electrodes allows for rapid and full entry into the electrode assembly 12.

[0162] There can be one second through hole 1421, through which the electrolyte enters the electrode assembly 12 from the periphery 142. Alternatively, there can be multiple second through holes 1421, which are circumferentially spaced around the first axis P. The electrolyte enters the multiple second through holes 1421, and the multiple second through holes 1421 together guide the electrolyte from the periphery 142 into the electrode assembly 12 to uniformly wet the electrode assembly 12 circumferentially. Alternatively, there can be multiple sets of second through holes 1421, which are circumferentially spaced around the first axis P. Each set of second through holes 1421 includes multiple second through holes 1421 spaced along the first direction R to fully guide the diffusion of the electrolyte in the first direction R.

[0163] The second through hole 1421 can be a round hole, or an elliptical hole, a square hole, a triangular hole, or a hole of other shapes.

[0164] With the above-described structure, the second through hole 1421 is provided in the surrounding portion 142, which can partially expose the gap between two adjacent electrode layers of the electrode assembly. The electrolyte can enter the gap between two adjacent electrode layers of the electrode assembly 12 through the second through hole 1421 to quickly and fully wet the electrode assembly 12.

[0165] like Figure 9 As shown, in some embodiments of this application, there are multiple second through holes 1421, and the multiple second through holes 1421 are arranged at intervals around the central portion 141.

[0166] like Figure 9 As shown, in some embodiments of this application, the shape and opening size of the plurality of second through holes 1421 can be the same, so that the liquid output of each second through hole 1421 is the same; the plurality of second through holes 1421 can be uniformly arranged around the central part 141 in a circumferential manner to guide the electrolyte to diffuse uniformly in a circumferential manner.

[0167] In other embodiments, the shape and opening size of the plurality of second through holes 1421 may also be different, and the plurality of second through holes 1421 may also be arranged non-uniformly around the center portion 141. By flexibly setting the opening position and number of the second through holes 1421, the space required by other components inside the battery cell 10 can be avoided and the strength of the current collector 14 can be improved, thus avoiding the transition portion 143 from having too many openings, which would make it easy to break.

[0168] like Figure 9As shown, in some embodiments of this application, the second through hole 1421 and the first through hole 1431 can be correspondingly arranged. Based on the aforementioned embodiment of "four first through holes 1431 are evenly spaced around the central portion 141", four first through holes 1431 and four second through holes 1421 are provided. The first through holes 1431 and the second through holes 1421 correspond one-to-one. The second through holes 1421 and the corresponding first through holes 1431 are spaced apart along the radial direction (i.e., the first direction R) of the battery cell 10 to guide the electrolyte to flow along the first direction R from the first through hole 1431 to the second through hole 1421, and then enter the electrode assembly 12 through the second through hole 1421.

[0169] In other embodiments, the number and location of the second through holes 1421 can be set independently of the number and location of the first through holes 1431. For example, four first through holes 1431 are provided, and the four first through holes 1431 are evenly spaced around the first axis P in the transition portion 143; six second through holes 1421 are provided, and the six second through holes 1421 are evenly spaced around the first axis P in the surrounding portion 142.

[0170] With the above-described structure, multiple second through holes 1421 are spaced apart around the central portion 141, which can guide the electrolyte to enter the gap between two adjacent electrode layers of the electrode assembly 12 around the circumference of the central portion 141, so as to quickly and fully wet the electrode assembly 12.

[0171] Figure 11 The diagram shown is a structural schematic of a third type of current collector in a battery cell according to some embodiments of this application; Figure 12 What is shown is Figure 11 A schematic diagram of the structure of the flow guide channel and the central hole of the flow collection component;

[0172] like Figure 11 and Figure 12 As shown, in some embodiments of this application, a first groove 1422 is provided on the side of the peripheral portion 142 away from the electrode assembly 12. The first groove 1422 is used to connect the first through hole 1431 and the second through hole 1421.

[0173] Along the thickness direction of the current collector 14, the side of the current collector 14 facing away from the electrode assembly 12 includes a first surface 144, and the side facing the electrode assembly 12 includes a second surface 145. A first groove 1422 is formed on the first surface 144.

[0174] The first groove 1422 can be formed by stamping or milling. One end of the first groove 1422 is connected to the first through hole 1431, and the other end can extend to the second through hole 1421; the first through hole 1431 can also be formed inside the first groove 1422, and the other end of the first groove 1422 extends to the edge of the surrounding portion 142; the first groove 1422 can extend along the first direction R, or it can extend spirally around the first axis P or extend along other directions.

[0175] Along the extending direction of the first groove 1422, the groove depth of the first groove 1422 can be the same to simplify the shape of the first groove 1422 and make the current collector 14 easier to process and form. The groove depth of the first groove 1422 can also vary along the extending direction of the first groove 1422 to guide the rapid diffusion of the electrolyte. For example, from the first through hole 1431 towards the second through hole 1421, the groove depth of the first groove 1422 gradually increases. The groove width of the first groove 1422 can also be the same to simplify the shape of the first groove 1422 and make the current collector 14 easier to process and form. The groove width of the first groove 1422 can also vary along the extending direction of the first groove 1422 to guide the rapid diffusion of the electrolyte. For example, from the first through hole 1431 towards the second through hole 1421, the groove width of the first groove 1422 gradually increases.

[0176] like Figure 11 As shown, in some embodiments of this application, the diameters of the first through hole 1431 and the second through hole 1421 are the same as the width of the first groove 1422 in the direction surrounding the first axis P, so as to reduce the opening area of ​​the first groove 1422 and make the current collecting member 14 stronger and less prone to breakage. In other embodiments, the width of the first groove 1422 may also be greater than the diameters of the first through hole 1431 and the second through hole 1421 to improve the diffusion rate of the electrolyte.

[0177] like Figure 11 As shown, based on the aforementioned embodiment of "four first through holes 1431 are evenly spaced around the central part 141, and the second through holes 1421 are correspondingly arranged with the first through holes 1431", four first grooves 1422 are provided, and the four first grooves 1422 are spaced around the first axis P. Each first groove 1422 connects the corresponding first through hole 1431 and the second through hole 1421.

[0178] With the above-described structure, the first groove 1422 is disposed on the side of the surrounding portion 142 away from the electrode assembly 12, and the first groove 1422 connects the first through hole 1431 and the second through hole 1421, which can guide the electrolyte to flow from the first through hole 1431 to the second through hole 1421 to enter the interior of the electrode assembly 12, and can increase the space on the side of the current collector 14 away from the electrode assembly 12, thereby increasing the diffusion rate of the electrolyte.

[0179] like Figure 11 As shown, in some embodiments of this application, the first groove 1422 extends radially along the electrode assembly 12 to the outer peripheral surface of the surrounding portion 142.

[0180] Specifically, the outer peripheral surface of the surrounding portion 142 surrounding the first axis P is the first outer peripheral surface 1424, and the first groove 1422 can extend along the first direction R, or extend spirally around the first axis P or extend in other directions.

[0181] like Figure 11 As shown, based on the aforementioned embodiment of "four first through holes 1431 are evenly spaced around the central portion 141, and second through holes 1421 are correspondingly arranged with the first through holes 1431", the first through holes 1431 and the corresponding second through holes 1421 are spaced apart along the first direction R, and the first groove 1422 extends along the first direction R to the first outer peripheral surface 1424 to connect the first through holes 1431 and the corresponding second through holes 1421.

[0182] With the above-described structure, the first groove 1422 extends to the outer peripheral surface of the surrounding portion 142, which can guide excess electrolyte to flow into the gap between the electrode assembly 12 and the housing 11, so that the electrolyte can quickly fill the interior of the housing 11 and fully wet the electrode assembly 12.

[0183] Figure 13 The diagram shown is a structural schematic of the insulating component in a battery cell according to some embodiments of this application; Figure 14 What is shown is Figure 13 A schematic diagram of the structure in which the insulating component and the current collecting component cooperate in guiding the current channel.

[0184] like Figure 13 and Figure 14 As shown, in some embodiments of this application, the battery cell 10 further includes an insulating member 16 disposed between the current collector 14 and the first wall for insulating and isolating the current collector 14 and the first wall. The insulating member 16 has a second groove 1611 on the side facing the current collector 14, and the second groove 1611 is used to connect the first through hole 1431 and the second through hole 1421.

[0185] The insulation member 16 extends along the first axis P in the thickness direction. The side of the insulation member 16 facing the current collecting member 14 includes a third surface 161, and the side facing the first wall includes a fourth surface 162. The second groove 1611 is provided on the third surface 161.

[0186] The shape of the insulating element 16 can match the shape of the housing 111. For example, when the housing 111 is a cylinder, the shape of the insulating element 16 is a circular plate structure. The shape of the insulating element 16 can also be set independently of the shape of the housing 111. For example, when the housing 111 is a cylinder, the shape of the insulating element 16 can be a square plate structure.

[0187] Based on the aforementioned embodiment where "the first wall is the bottom wall 1111", the insulating member 16 is made of lower plastic to insulate and isolate the current collector 14 from the bottom wall 1111. The insulating member 16 may also be an additional component provided to promote electrolyte diffusion.

[0188] The insulating component 16 can be injection molded, and the second groove 1611 can be formed directly on the third surface 161 of the insulating component 16, or it can be formed by planing. One end of the second groove 1611 communicates with the first through hole 1431, and the other end can extend to the second through hole 1421; the second groove 1611 can also extend to the edge of the insulating component 16, and on the plane perpendicular to the first axis P, the projection of the second through hole 1421 falls within the projection range of the second groove 1611; the second groove 1611 can extend along the first direction R, or it can extend spirally around the first axis P or extend in other directions.

[0189] Along the extending direction of the second groove 1611, the groove depth of the second groove 1611 can be the same to simplify the shape of the second groove 1611 and make the insulating member 16 easier to process and form. The groove depth of the second groove 1611 can also vary along the extending direction of the second groove 1611 to guide the rapid diffusion of the electrolyte. For example, from the first through hole 1431 towards the second through hole 1421, the groove depth of the second groove 1611 gradually increases. The groove width of the second groove 1611 can be the same to simplify the shape of the second groove 1611 and make the current collector 14 easier to process and form. The groove width of the second groove 1611 can also vary along the extending direction of the second groove 1611 to guide the rapid diffusion of the electrolyte. For example, from the first through hole 1431 towards the second through hole 1421, the groove width of the second groove 1611 gradually increases.

[0190] In the direction surrounding the first axis P, the diameters of the first through hole 1431 and the second through hole 1421 and the width of the second groove 1611 can be the same to reduce the opening area of ​​the second groove 1611, thereby increasing the strength of the current collecting member 14 and making it less prone to breakage; the width of the second groove 1611 can also be greater than the diameters of the first through hole 1431 and the second through hole 1421 to increase the diffusion rate of the electrolyte.

[0191] The second groove 1611 can be provided corresponding to the first groove 1422 to improve the diffusion rate of the electrolyte. For example, based on the aforementioned embodiment in which "four first through holes 1431 are evenly spaced around the center portion 141, second through holes 1421 are provided corresponding to the first through holes 1431, four first grooves 1422 are provided, and each first groove 1422 connects the corresponding first through hole 1431 and the second through hole 1421", four second grooves 1611 are also provided. On the plane perpendicular to the first axis P, the projected contours of the first groove 1422 and the corresponding second groove 1611 coincide.

[0192] The second groove 1611 can also be set independently of the first groove 1422 to simplify the assembly and positioning requirements of the current collecting member 14 and the insulating member 16. For example, on a plane perpendicular to the first axis P, the projected contours of the first groove 1422 and the corresponding second groove 1611 do not completely coincide; for another example, such as Figure 16 As shown, the first surface 144 of the current collector 14 does not have a first groove 1422, and the first through hole 1431 and the corresponding second through hole 1421 are connected only through the second groove 1611.

[0193] With the above structure, the electrolyte flowing out from the first through hole 1431 enters the gap between the insulating member 16 and the current collector 14. The second groove 1611 can guide the electrolyte to flow from the first through hole 1431 to the second through hole 1421, so that the electrolyte enters the interior of the electrode assembly 12. It can also increase the space on the side of the current collector 14 away from the electrode assembly 12 and improve the diffusion rate of the electrolyte.

[0194] In some embodiments of this application, the second groove 1611 extends radially along the electrode assembly 12 to the outer peripheral surface of the insulator 16.

[0195] Specifically, the outer peripheral surface of the insulating member 16 surrounding the first axis P is the second outer peripheral surface 163. The second groove 1611 may extend along the first direction R, or may extend spirally around the first axis P or extend in other directions.

[0196] Based on the aforementioned implementation method of "four first through holes 1431 are evenly spaced around the central portion 141, and second through holes 1421 are correspondingly arranged with the first through holes 1431", the first through holes 1431 and the corresponding second through holes 1421 are spaced apart along the first direction R, and four second grooves 1611 are provided. Each second groove 1611 extends along the first direction R to the second outer peripheral surface 163 to connect the first through holes 1431 and the corresponding second through holes 1421.

[0197] With the above-described structure, the second groove 1611 extends to the outer peripheral surface of the insulating member 16, which can guide excess electrolyte to flow into the gap between the electrode assembly 12 and the housing 11, so that the electrolyte can quickly fill the interior of the housing 11 and fully wet the electrode assembly 12.

[0198] Figure 15 The diagram shown is a structural schematic of a fourth type of current collector in a battery cell according to some embodiments of this application; Figure 16 What is shown is Figure 15 A schematic diagram of the structure of the flow guide channel and the central hole of the flow collection component;

[0199] like Figure 15 and Figure 16 As shown, in some embodiments of this application, the flow channel is a third groove 1423, which is disposed on the side of the peripheral portion 142 facing the electrode assembly 12, and the third groove 1423 communicates with the central hole 1211.

[0200] Specifically, the second surface 145 of the current collector 14 is provided with a third groove 1423. One end of the third groove 1423 extends to the center portion 141 to communicate with the central hole 1211, and the other end can extend to the edge of the current collector 14 or to the peripheral portion 142. Based on the aforementioned embodiment in which "the center portion 141 protrudes from the peripheral portion 142 toward the electrode terminal 13", one end of the third groove 1423 communicates with the liquid storage space 146 to achieve communication with the central hole 1211.

[0201] The third groove 1423 can be formed by stamping or milling. The third groove 1423 can extend along the first direction R, or extend spirally around the first axis P, or extend in other directions.

[0202] Along the extension direction of the third groove, the depth of the third groove 1423 can be the same to simplify its shape and make the current collector 14 easier to process and shape. Alternatively, the depth of the third groove 1423 can vary along its extension direction to guide rapid electrolyte diffusion; for example, the depth of the third groove 1423 gradually increases from the center 141 to the surrounding portion 142. The width of the third groove 1423 can also be the same to simplify its shape and make the current collector 14 easier to process and shape. Alternatively, the width of the third groove 1423 can vary along its extension direction to guide rapid electrolyte diffusion; for example, the width of the third groove 1423 gradually increases from the center 141 to the surrounding portion 142.

[0203] There can be one third groove 1423, through which the electrolyte diffuses from the center 141 to the surrounding part 142. Alternatively, there can be multiple third grooves 1423, which are circumferentially distributed around the first axis P. The electrolyte enters multiple third grooves 1423, and the multiple third grooves 1423 together guide the electrolyte to diffuse from the center 141 to the surrounding part 142, so as to uniformly wet the electrode assembly 12 circumferentially.

[0204] With the above structure, the electrolyte in the central hole 1211 enters the gap between the electrode assembly 12 and the current collector 14, and the third groove 1423 can guide the electrolyte to diffuse to the surrounding part 142, thereby increasing the diffusion rate of the electrolyte.

[0205] In some embodiments of this application, the third groove 1423 extends radially along the electrode assembly 12 to the outer peripheral surface of the surrounding portion 142.

[0206] The third groove 1423 can extend along the first direction R, or it can extend spirally around the first axis P or extend in other directions. Based on the aforementioned embodiment in which "multiple third grooves 1423 are circumferentially spaced around the first axis P", one end of the third groove 1423 is connected to the central hole 1211, and the other end extends along the first direction R to the first outer peripheral surface 1424 of the surrounding portion 142; based on the aforementioned embodiment in which "one third groove 1423 can be provided", one end of the third groove 1423 is connected to the central hole 1211, and the other end extends spirally around the first axis P to the first outer peripheral surface 1424 of the surrounding portion 142.

[0207] With the above-described structure, the third groove 1423 extends to the outer peripheral surface of the surrounding portion 142, which can guide excess electrolyte to flow into the gap between the electrode assembly 12 and the housing 11, so that the electrolyte can quickly fill the interior of the housing 11 and fully wet the electrode assembly 12.

[0208] Some embodiments of this application provide a battery 100, including a battery cell 10.

[0209] Some embodiments of this application provide an electrical device including a battery 100.

[0210] Figure 17 The diagram shown illustrates a method for manufacturing a single battery cell according to some embodiments of this application.

[0211] like Figure 17 As shown, some embodiments of this application propose a method for manufacturing a battery cell 10, including:

[0212] S100: Provides a housing 111 and an electrode terminal 13. The housing 111 includes a bottom wall 1111 and a side wall 1112. The side wall 1112 surrounds the bottom wall 1111. One end of the side wall 1112 is connected to the bottom wall 1111, and the other end forms an opening 113. The electrode terminal 13 is insulated and installed on the bottom wall 1111.

[0213] S200: Provide an electrode assembly 12, the electrode assembly 12 having a central hole 1211, a first tab 122 formed at one end of the electrode assembly 12, and a second tab 123 formed at the other end;

[0214] S300: A flow collecting component 14 is provided, which includes a central part 141 and a peripheral part 142, and a flow guiding channel is provided on the flow collecting component 14;

[0215] S400: Provides an end cap 112, on which an injection hole 1121 is provided;

[0216] S500: Connect the peripheral portion 142 to the first electrode tab 122, make the central portion 141 correspond to the central hole 1211, put the electrode assembly 12 into the housing 111, make the current collector 14 between the bottom wall 1111 and the electrode assembly 12, and connect the central portion 141 to the electrode terminal 13.

[0217] S600: Cover the opening 113 with the end cap 112 and connect it with the second electrode tab 123 so that the position of the injection hole 1121 corresponds to the position of the center hole 1211;

[0218] S700: Electrolyte is injected into the interior of the housing 111 through the injection hole 1121. The electrolyte enters the central hole 1211 and diffuses from the center 141 to the surrounding part 142 through the guide channel.

[0219] Figure 18 The diagram shown is a schematic of a battery cell manufacturing apparatus according to some embodiments of this application.

[0220] like Figure 18As shown, some embodiments of this application disclose a manufacturing apparatus 2000 for a battery cell 10, comprising:

[0221] The first providing device 2100 is used to provide a housing 111 and an electrode terminal 13. The housing 111 includes a bottom wall 1111 and a side wall 1112. The side wall 1112 surrounds the bottom wall 1111. One end of the side wall 1112 is connected to the bottom wall 1111, and the other end forms an opening 113. The electrode terminal 13 is insulated and installed on the bottom wall 1111.

[0222] The second providing device 2200 is used to provide an electrode assembly 12, the electrode assembly 12 having a central hole 1211, a first tab 122 formed at one end of the electrode assembly 12, and a second tab 123 formed at the other end;

[0223] The third providing device 2300 is used to provide a flow collecting component 14, which includes a central part 141 and a peripheral part 142, and a flow guiding channel is provided on the flow collecting component 14.

[0224] The fourth supplying device 2400 is used to supply an end cap 112, on which an injection hole 1121 is provided;

[0225] The first assembly module 2500 is used to connect the peripheral part 142 to the first tab 122, so that the central part 141 corresponds to the central hole 1211, to put the electrode assembly 12 into the housing 111, so that the current collector 14 is located between the bottom wall 1111 and the electrode assembly 12, to connect the central part 141 to the electrode terminal 13, to cover the opening 113 with the end cap 112 and connect it to the second tab 123, so that the liquid injection hole 1121 corresponds to the central hole 1211.

[0226] The second assembly module 2600 is used to inject electrolyte into the interior of the housing 111 through the injection hole 1121. The electrolyte enters the central hole 1211 and diffuses from the center 141 to the surrounding part 142 through the guide channel.

[0227] like Figure 3 , Figure 4 , Figure 11 and Figure 12As shown, some embodiments of this application propose a cylindrical battery, including a casing 111, an end cap 112, an electrode assembly 12, electrode terminals 13, a positive current collector, rivets, and a lower plastic layer. The end cap 112 has a liquid injection hole 1121, which is sealed with rivets. The electrode assembly 12 includes a positive electrode tab and a negative electrode tab. The positive electrode tab is connected to the bottom wall 1111 of the casing 111 via the positive current collector. The lower plastic layer provides insulation between the positive current collector and the bottom wall 1111. The negative electrode tab makes rigid contact with the end cap 112 via the negative current collector. The center of the positive current collector protrudes towards the bottom wall 1111 to form a central portion 141, and a peripheral portion 142 is circumferentially arranged around the central portion 141. The raised sidewall is provided with a first through hole 1431. The surface of the peripheral portion 142 on the same side as the first through hole 1431 is recessed to form a first groove 1422. The first groove 1422 extends radially along the positive electrode current collector, and a second through hole 1421 is formed inside the radially extending first groove 1422. The second through hole 1421 is used for electrolyte distribution. During electrolyte injection, the electrolyte injection hole 1121 of the cylindrical battery is located on the bottom side. The electrolyte flows upward from the central hole 1211 of the electrode assembly 12, enters the first groove 1422 through the first through hole 1431 of the positive electrode current collector, and diffuses radially. It flows to the gap between the housing 111 and the electrode assembly 12, and enters the electrode assembly 12 through the second through hole 1421, thereby improving the electrolyte wettability of the entire cylindrical battery.

[0228] The positive current collector has a hollowed-out area on its raised sidewall that exceeds half its circumference to function as a fuse. The groove on the bottom wall 1111 of the positive current collector communicates with the first through-hole 1431 to guide the electrolyte into the first groove 1422. Each first groove 1422 can have one, two, or more second through-holes, and their shapes can be circular, triangular, square, elliptical, etc.

[0229] like Figure 3 , Figure 4 , Figure 13 and Figure 14 As shown, some embodiments of this application propose a cylindrical battery, including a casing 111, an end cap 112, an electrode assembly 12, electrode terminals 13, a positive current collector, rivets, and a lower plastic layer. The positive current collector has a first through hole 1431 and a second through hole 1421. The surface of the lower plastic layer facing the positive current collector has a second groove 1611, which mates with the first through hole 1431 and the second through hole 1421. During electrolyte injection, the electrolyte enters the second groove 1611 from the first through hole 1431 and diffuses radially, flowing to the gap between the casing 111 and the electrode assembly 12, and entering the electrode assembly 12 through the second through hole 1421, thereby improving the electrolyte wettability of the entire cylindrical battery.

[0230] The width of the second groove 1611, the height of the center protrusion of the positive current collector, and the diameter of the second through hole 1421 are the same.

[0231] like Figure 3 , Figure 4 , Figure 15 and Figure 16 As shown, some embodiments of this application propose a cylindrical battery, including a casing 111, an end cap 112, an electrode assembly 12, electrode terminals 13, a positive current collector, rivets, and a lower plastic layer. The positive current collector protrudes towards the bottom wall 1111 to form a central portion 141, and a peripheral portion 142 is disposed around the central portion 141. A third groove 1423 is provided on the surface of the peripheral portion 142 facing the electrode assembly 12, and the third groove 1423 extends radially along the positive current collector. During electrolyte injection, the electrolyte flows upward from the central hole 1211 of the electrode assembly 12, diffuses radially within the central protrusion of the positive current collector and the third groove 1423, and flows towards the gap between the casing 111 and the electrode assembly 12 and the electrode assembly 12, improving the electrolyte wettability of the entire cylindrical battery.

[0232] The number of third grooves 1423 can be two to six, and multiple third grooves 1423 are arranged circumferentially at intervals on the positive electrode current collector.

[0233] It should be noted that, where there is no conflict, the features in the embodiments of this application can be combined with each other.

[0234] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A battery cell, characterized in that, include: The outer shell, including the first wall; Electrode terminals are insulated and mounted on the first wall; An electrode assembly is disposed within the housing, the electrode assembly having a central hole, and a first tab formed at the end of the electrode assembly facing the first wall. A current collector is disposed between the first wall and the electrode assembly. The current collector includes a central portion and a peripheral portion. The central portion corresponds to the position of the central hole. The central portion is used to connect the electrode terminal, and the peripheral portion is used to connect the first electrode tab. The current collector is provided with a flow guiding channel, which is a first through hole located at the edge of the central part. The central part protrudes from the surrounding part in the direction of the electrode terminal. The current collector also includes a transition part surrounding the central part and connecting the central part and the surrounding part. The first through hole is disposed in the transition part. The flow guiding channel is configured to guide the electrolyte in the central hole to diffuse from the central part to the surrounding part. The number of first through holes is one, and the length of the first through hole along the circumference of the central portion is greater than or equal to 1 / 2 of the circumference of the transition portion; or, the number of first through holes is multiple, and the total length of the multiple first through holes along the circumference of the central portion is greater than or equal to 1 / 2 of the circumference of the transition portion.

2. The battery cell according to claim 1, characterized in that, Multiple first through holes are spaced apart around the central portion.

3. The battery cell according to claim 1, characterized in that, The first through hole is an arc-shaped hole extending circumferentially along the center portion.

4. The battery cell according to claim 1, characterized in that, A second through hole is provided on the surrounding portion, and the second through hole is further away from the center portion relative to the first through hole.

5. The battery cell according to claim 4, characterized in that, The number of the second through holes is multiple, and the multiple second through holes are spaced apart around the central part.

6. The battery cell according to claim 4, characterized in that, A first groove is provided on the side of the surrounding portion opposite to the electrode assembly, and the first groove is used to connect the first through hole and the second through hole.

7. The battery cell according to claim 6, characterized in that, The first groove extends radially along the electrode assembly to the outer peripheral surface of the surrounding portion.

8. The battery cell according to any one of claims 4-7, characterized in that, The battery cell also includes: An insulating component is disposed between the current collecting member and the first wall to insulate and isolate the current collecting member from the first wall. The side of the insulating component facing the current collecting member is provided with a second groove, which is used to connect the first through hole and the second through hole.

9. The battery cell according to claim 8, characterized in that, The second groove extends radially along the electrode assembly to the outer peripheral surface of the insulator.

10. The battery cell according to claim 1, characterized in that, The flow channel is a third groove, which is located on the side of the surrounding portion facing the electrode assembly and is connected to the central hole.

11. The battery cell according to claim 10, characterized in that, The third groove extends radially along the electrode assembly to the outer peripheral surface of the surrounding portion.

12. The battery cell according to claim 1, wherein, The outer casing further includes a second wall, which is disposed opposite to the first wall along the axial direction of the central hole. A liquid injection hole is provided on the second wall at a position corresponding to the central hole. The battery cell further includes: A sealing element for closing the injection hole.

13. The battery cell according to claim 12, characterized in that, The electrode assembly has a second tab at one end facing the second wall. The first tab and the second tab have opposite polarities, and the second tab is electrically connected to the second wall.

14. The battery cell according to claim 12, characterized in that, The outer casing includes a housing and an end cap. The housing includes a bottom wall and a side wall. The side wall surrounds the bottom wall. One end of the side wall is connected to the bottom wall, and the other end forms an opening. The end cap covers the opening. The first wall is the bottom wall, and the second wall is the end cap.

15. A battery, characterized in that, Includes the battery cell as described in any one of claims 1-14.

16. An electrical appliance, characterized in that, Includes the battery as described in claim 15.

17. A method for manufacturing a battery cell, used in the battery cell as described in any one of claims 1-14, characterized in that, include: A housing and electrode terminals are provided. The housing includes a bottom wall and a side wall. The side wall surrounds the bottom wall, with one end connected to the bottom wall and the other end forming an opening. The electrode terminals are insulated and mounted on the bottom wall. An electrode assembly is provided, the electrode assembly having a central hole, a first tab being formed at one end of the electrode assembly, and a second tab being formed at the other end; A flow collecting component is provided, the flow collecting component including a central part and a surrounding part, and a flow guiding channel is provided on the flow collecting component; An end cap is provided, wherein the end cap is provided with a liquid injection hole; Connect the peripheral portion to the first electrode tab, align the central portion with the central hole, place the electrode assembly into the housing, position the current collector between the bottom wall and the electrode assembly, and connect the central portion to the electrode terminal. Cover the opening with the end cap and connect it to the second electrode tab, so that the injection hole corresponds to the position of the center hole; Electrolyte is injected into the interior of the housing through the injection hole. The electrolyte enters the central hole and diffuses from the center to the surrounding area through the flow channel.

18. A manufacturing apparatus for a battery cell, used in any one of claims 1-14, characterized in that, include: A first providing device is used to provide a housing and electrode terminals. The housing includes a bottom wall and a side wall. The side wall surrounds the bottom wall. One end of the side wall is connected to the bottom wall, and the other end forms an opening. The electrode terminals are insulated and mounted on the bottom wall. A second providing device is used to provide an electrode assembly having a central hole, a first tab being formed at one end of the electrode assembly, and a second tab being formed at the other end; A third providing device is used to provide a flow collecting component, the flow collecting component including a central part and a peripheral part, and a flow guiding channel is provided on the flow collecting component; The fourth providing device is used to provide an end cap, wherein the end cap is provided with a liquid injection hole; The first assembly module is used to connect the peripheral portion to the first tab, align the central portion with the central hole, place the electrode assembly into the housing, position the current collector between the bottom wall and the electrode assembly, connect the central portion to the electrode terminal, cover the opening with the end cap and connect it to the second tab, and align the injection hole with the central hole. The second assembly module is used to inject electrolyte into the interior of the housing through the injection hole. The electrolyte enters the central hole and diffuses from the center to the surrounding area through the flow channel.

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