Current collector plate, cover plate assembly and battery cell

Abstract

The application provides a current collecting plate, a cover plate assembly and a battery cell. The current collecting plate comprises a disc body, a tail part and an overcurrent component; one end of the tail part is connected to one end of the disc body; the overcurrent component is connected to the disc body, and in an unfolded state of the current collecting plate, the overcurrent component is arranged away from the tail part, and the overcurrent component is configured to be in contact with the tail part in a folded state of the current collecting plate. Through the above scheme, the overcurrent component can be arranged in the folding gap of the current collecting plate in the folded state to control the height size of the current collecting plate in the folded state, so as to avoid affecting the height size of the battery cell, and the current collecting plate can also realize overcurrent through the contact between the overcurrent component and the tail part in addition to the connection part between the disc body and the tail part, so as to increase the overcurrent area between the disc body and the tail part and shorten the overcurrent path between the disc body and the tail part. In this way, the resistance of the current collecting plate can be reduced, the Joule heat generated in the charging and discharging process of the battery cell can be reduced, and the overcurrent capacity of the battery cell can be improved.

Description

Technical Field

[0001] This application relates to the field of battery technology, specifically to a current collector, a cover plate assembly, and a battery cell. Background Technology

[0002] Battery cells (also known as battery units or single-cell batteries) are mainly divided into rechargeable secondary batteries and non-rechargeable primary batteries based on whether they are rechargeable. In related technologies, a battery cell includes a cover assembly, a housing, and an electrode assembly. The cover assembly includes a cover plate, a current collector, and terminals. The cover plate closes to the housing to define a cavity for containing the electrolyte and the electrode assembly. The terminals pass through the cover plate and are connected to the electrode assembly via the current collector.

[0003] As the requirements for battery charging and discharging power increase, the size of components involved in current flow in the battery cell is also increased to improve current flow capacity. However, the internal space of the battery cell is limited, and the size of components involved in current flow cannot be increased indefinitely. Therefore, how to improve the current flow capacity of the battery cell without affecting its size is the problem that this application aims to solve. Utility Model Content

[0004] The embodiments of this application provide a current collector, a cover plate assembly, and a battery cell, which can improve the current carrying capacity of the battery cell without affecting the battery cell size.

[0005] Firstly, embodiments of this application provide a current collector, which includes a plate body, a tail section, and a current-carrying component. One end of the tail section is connected to one end of the plate body. The current-carrying component is connected to the plate body. When the current collector is in an unfolded state, the current-carrying component is positioned away from the tail section. The current-carrying component is configured to contact the tail section when the current collector is in a bent state. This allows the current collector to carry current not only through the connection between the plate body and the tail section but also through the current-carrying component. This not only increases the current-carrying area between the plate body and the tail section, thus improving the current-carrying capacity of the current collector, but also allows some current to bypass the connection between the plate body and the tail section and flow directly through the current-carrying component, shortening the current-carrying path between the plate body and the tail section. This reduces the resistance of the current collector, thereby reducing Joule heating generated by the battery cell during charging and discharging, and thus improving the charging and discharging efficiency of the battery cell.

[0006] In some embodiments, when the collector plate is in the deployed state, the collector plate has a length direction, and along the length direction, the plate body has a width dimension D, and the flow-through component has a width dimension B, satisfying: 3mm≤B≤50%D. This avoids the flow-through component's width dimension B being too small, which would be detrimental to molding, and also avoids the flow-through component's width dimension B being too large, which would affect the welding of the collector plate and the electrode tab.

[0007] In some embodiments, the diameter of the disk body is φd, the collector disk has a width direction, and along the width direction, the flow-through component has a length dimension A, satisfying: 5mm≤A≤35%φd; wherein, the width direction is perpendicular to the length direction of the collector disk and parallel to the plane on which the disk body is located. This avoids the flow-through component's length dimension A being too small, which would be detrimental to molding, and also avoids the flow-through component's length dimension A being too large, which would affect the welding of the collector disk and the electrode tab.

[0008] In some embodiments, the distance between the end of the current-carrying element facing away from the disk and the disk is δH, satisfying: 0.5mm≤δH≤5mm. This ensures, on the one hand, that the current-carrying element has sufficient height to contact the tail end, achieving current stability between the current-carrying element and the tail end; on the other hand, it avoids the current-carrying element being too large and occupying too much internal space of the cell, thus helping to ensure a high energy density in the cell.

[0009] In some embodiments, when projected onto a plane parallel to the disk body, the projected area of ​​the flow element away from the disk body is S1, and the area enclosed by the projection of the outer edge line of the end where the flow element connects to the disk body is S2, satisfying: S1 < S2. This allows the flow element to present a structure similar to a cone or stepped shape with a narrow top and wide bottom, thereby reducing the stress at the connection between the flow element and the disk body, improving the stress state at the connection between the flow element and the disk body, and thus enhancing the structural reliability of the collector disk.

[0010] In some embodiments, the surface of the flow element facing away from the disk body is a first surface, and the outer surface of the flow element located between the first surface and the disk body is a first circumferential surface; wherein, a chamfer is provided at the connection between the first surface and the first circumferential surface; And / or, a chamfer is provided at the connection between the first ring circumferential surface and the disk body. In this way, the projected area S2 of the end of the flow element connected to the disk body can be made larger than the projected area S1 of the surface of the flow element away from the disk body, and the structure of the flow element can be made simple and easy to form.

[0011] In some embodiments, when projected onto a plane parallel to the disk body, the projected area of ​​the flow element away from the surface of the disk body is S1, and the area enclosed by the projection of the outer edge line of the disk body is S, satisfying: 15mm 2 ≤S1≤70%S. In this way, the surface of the flow element away from the disk body can have a suitable contact area with the tail to ensure the flow capacity between the flow element and the tail, while avoiding the surface area of ​​the flow element away from the disk body being too large, which would affect the setting of other structures on the disk body; And / or, the disk body is provided with a core positioning structure, and when the collector disk is in the unfolded state, the flow passage component is located on the side of the core positioning structure away from the tail.

[0012] In some embodiments, a groove is provided on the side of the disk body away from the current-carrying element. The groove is disposed opposite to the current-carrying element, and the end of the groove away from the slot opening is disposed inside the current-carrying element. In this way, the current-carrying element can have a larger contact area with the tail end, and the material used in the current-carrying disk can be reduced to reduce the weight of the current-carrying disk, thereby helping to improve the energy density of the battery cell.

[0013] In some embodiments, the thickness of the current-carrying element is less than the thickness of the disk body; this shortens the heat conduction path of the current-carrying element, improves the efficiency of the current-carrying element, thereby improving the heat dissipation efficiency of the current collector disk, and thus improving the heat dissipation efficiency of the battery cell. And / or, the flow element is integrated with the disk body. This reduces the number of connection points on the collector disk, thereby reducing stress concentration at the connection points between the flow element and the disk body, and thus improving the reliability of the connection between the flow element and the disk body.

[0014] In some embodiments, the disk body protrudes outward from the side opposite to the current-carrying element, forming a first recess on the side of the disk body near the current-carrying element and a first protrusion on the side of the disk body opposite to the current-carrying element; wherein the first recess is located close to the current-carrying element. This allows a torque with its torsional center located between the first protrusion and the current-carrying element to be formed on the disk body, increasing the elasticity of the current-carrying disk and thus increasing the compression of the current-carrying disk. In this way, while reducing the internal space occupied by the current-carrying disk within the cell, the contact force between the current-carrying element and the tail section, as well as the contact force between the first protrusion and the electrode assembly, is increased, thereby improving the current-carrying reliability of the current-carrying disk.

[0015] In some embodiments, the tail portion includes a first sub-portion and a second sub-portion, the second sub-portion connecting the first sub-portion and the disk body; wherein, when the current collector is in a bent state, the second sub-portion is folded between the first sub-portion and the disk body. This increases the elasticity of the current collector in the bent state, thereby increasing the compression of the current collector, enabling it to maintain stable contact with the electrode post and electrode assembly, thus improving the reliability of the connection between the current collector and the electrode post and electrode assembly.

[0016] In some embodiments, when the collector plate is in its unfolded state, the collector plate has a length direction, along which the second sub-part has a length dimension C, and the flow passage component has a width dimension B, satisfying: 3mm ≤ B ≤ 70% C. This avoids the flow passage component's width dimension B being too small, which would be detrimental to molding, and also avoids the flow passage component's width dimension B being too large, which would affect the structural design of the collector plate, making the forming process of the collector plate simple and easy to manufacture.

[0017] In some embodiments, when the collector plate is in its deployed state, the collector plate has a length direction, and electrode welding areas are provided on both sides of the plate body along the length direction; wherein, the flow-through component is located between the electrode welding areas. In this way, the collector plate can have a large electrode welding area, while avoiding the flow-through component from affecting the welding between the collector plate and the electrode.

[0018] In some embodiments, the disc body protrudes outward on the side opposite to the current-flowing element to form a protruding tab welding area on the side of the disc body opposite to the current-flowing element, and a second recess is formed on the side of the disc body close to the current-flowing element; thus, a gap is formed between the disc body and the electrode assembly to facilitate electrolyte flow and improve the wetting efficiency of the electrode assembly; And / or, there are two tab welding areas, which are symmetrically distributed about the center of the disk. This improves the structural symmetry of the current collector, which helps to improve the uniformity of stress on the current collector, thereby improving the reliability of the cell.

[0019] In some embodiments, the disc body is provided with a pressure relief port; this allows the high-pressure fluid inside the battery cell to quickly flow into the explosion-proof valve of the battery cell through the pressure relief port, causing the explosion-proof valve to open rapidly for venting and pressure relief, thus ensuring the reliability of the battery cell; And / or, a through groove is provided at the bending section of the collector plate, extending along the center line of the bend. When the collector plate is bent, the through groove is located on the concave surface of the collector plate. This reduces the obstruction of the bend at the concave surface of the collector plate, thereby improving the smoothness of the bend.

[0020] Secondly, embodiments of this application provide a cover plate assembly, which includes a cover plate, an electrode post, a lower plastic component, and the aforementioned current collector; the electrode post passes through the cover plate; the tail end away from the plate body is connected to the electrode post; the lower plastic component is disposed between the cover plate and the current collector. This reduces the resistance of the current collector, thereby reducing Joule heat generated by the battery cell during charging and discharging, and thus improving the charging and discharging efficiency of the battery cell.

[0021] Thirdly, embodiments of this application provide a battery cell comprising a housing, an electrode assembly, and the aforementioned cover assembly; the electrode assembly is disposed within the housing; the cover is closed to the housing, a current collector is connected to the electrode assembly, and a current collector is folded and disposed between the electrode assembly and the cover. This reduces the resistance of the current collector, thereby reducing Joule heat generated during charging and discharging, and thus improving the charging and discharging efficiency of the battery cell.

[0022] The beneficial effects of the embodiments of this application are as follows: In the embodiments of this application, by setting a current-carrying element and making it contact the tail end when the current collector is bent, the current-carrying element can be arranged using the bending gap of the current collector in the bent state to control the height of the current collector in the bent state and avoid affecting the height of the battery cell. Furthermore, the current collector can carry current not only through the connection between the plate body and the tail end, but also through the contact between the current-carrying element and the tail end. This not only increases the current-carrying area between the plate body and the tail end, thus improving the current-carrying capacity of the current collector, but also allows some current to bypass the connection between the plate body and the tail end and flow directly through the current-carrying element, shortening the current-carrying path between the plate body and the tail end. This reduces the resistance of the current collector, thereby reducing Joule heat generated by the battery cell during charging and discharging, and thus improving the current-carrying capacity of the battery cell. Attached Figure Description

[0023] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0024] Figure 1 This is a schematic diagram of the battery cell structure provided in an embodiment of this application; Figure 2 This is a schematic diagram of the structure of the cover plate assembly provided in an embodiment of this application; Figure 3 This is a schematic diagram of the collector disk in its deployed state, provided in an embodiment of this application. Figure 4 This is a side view of the manifold in a bent state provided in an embodiment of this application; Figure 5 This is a side view of the data collector in its deployed state, provided in an embodiment of this application; Figure 6 yes Figure 3 A magnified structural diagram of section E in the middle; Figure 7 yes Figure 5 A cross-sectional view of GG; Figure 8 This is a side view of another manifold in a bent state provided in an embodiment of this application.

[0025] Explanation of reference numerals in the attached figures: 1000 - Cell; 200 - Housing; 300 - Electrode assembly; 100-Cover assembly; 101-Cover; 102-Pole post; 103-Lower plastic part; 104-Upper plastic part; 105-Terminal; 106-Explosion-proof valve; 10-Collector disk; 11-Disc body; 111-Core positioning structure; 112-Groove; 113-First recess; 114-First protrusion; 115-Electrode welding area; 116-Second recess; 117-Pressure relief outlet; 118-Through groove; 12-Tail section; 121-First sub-section; 122-Second sub-section; 123-Slot; 124-Protrusion hull; 13-Flow passage component; 131-First surface; 132-First circumferential surface; 133-Chamfer. Detailed Implementation

[0026] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and 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.

[0027] Furthermore, it should be understood that the specific embodiments described herein are for illustrative and explanatory purposes only and are not intended to limit the scope of this application. In this application, unless otherwise stated, directional terms such as "upper" and "lower" generally refer to the upper and lower positions of the device in its actual use or operation, specifically the directions shown in the accompanying drawings; while "inner" and "outer" refer to the outline of the device.

[0028] The terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the stated features. In the description of this application, "a plurality of" means two or more, unless otherwise explicitly specified.

[0029] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "linking" 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 mechanical connection, an electrical connection, or a connection that allows communication between them; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication between two components or the interaction 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.

[0030] The terms “comprising,” “including,” or any other variations thereof are intended to cover non-exclusive inclusion, such that a product that comprises a list of elements includes not only those elements but also other elements not expressly listed or inherent to such a product.

[0031] Before introducing the current collector, cover plate assembly, and battery cell provided in the embodiments of this application, the relevant technologies of this application will be introduced first. In the relevant technologies, as the requirements for battery charging and discharging power increase, the components of the battery cell involving current flow are also increased in size to improve the current flow capacity. For example, the thickness of the current collector can be increased to improve the current flow capacity of the current collector. However, due to the limited internal space of the battery cell, the increase in the thickness of the current collector is limited, resulting in a not significant improvement in the current flow capacity of the current flow components.

[0032] Furthermore, to improve the ease of welding the current-carrying components to the terminals and electrode assemblies, the current collector is designed as a bent component. That is, during cell assembly, the current collector is flattened, with one end welded to the terminal and the other end welded to the tab of the electrode assembly. After welding, the current collector is bent, folding it along the axial direction of the cell so that it is positioned between the electrode assembly and the cover plate. This results in a longer current path when current flows through the current collector, requiring the current to be transferred from one end to the other. A longer current path means an increased conductive distance for the current collector. According to the resistance formula R=ρL / S (where ρ is resistivity, L is the current path length, and S is the cross-sectional area of ​​the current path), an increased current path length L directly leads to an increase in the current collector's own resistance R. Increased resistance leads to increased Joule heat generated during cell charging and discharging, resulting in a decrease in the cell's charging and discharging efficiency.

[0033] Based on this, embodiments of this application provide a current collector, a cover plate assembly, and a battery cell, which can effectively improve the current carrying capacity of the current collector and shorten the current carrying path of the current carrying components, thereby improving the charging and discharging efficiency of the battery cell.

[0034] The following combination Figures 1 to 8 The present application provides a detailed description of a current collector 10, a cover plate assembly 100, and a battery cell 1000 provided in the embodiments of this application.

[0035] Please see Figure 1 This application provides a battery cell 1000, which includes a housing 200, an electrode assembly 300, and a cover plate assembly 100. The electrode assembly 300 is disposed within the housing 200. The cover plate 101 of the cover plate assembly 100 covers the housing 200, and the terminal post 102 of the cover plate assembly 100 is connected to the electrode assembly 300.

[0036] Understandably, the housing 200 is also used to store electrode liquid.

[0037] It is understood that in the embodiments of this application, the battery cell 1000 may include a lithium-ion secondary battery, a lithium-ion primary battery, a lithium-sulfur battery, a sodium-lithium-ion battery, a sodium-ion battery, or a magnesium-ion battery, etc., and the embodiments of this application are not limited thereto. The battery cell 1000 may be cylindrical, flat, cuboid, or other shapes, etc., and the embodiments of this application are not limited thereto.

[0038] The electrode assembly 300 includes a positive electrode, a separator, and a negative electrode stacked sequentially. The separator insulates and isolates the positive and negative electrodes and provides channels for the flow of metal ions. The cell 1000 primarily relies on the movement of metal ions between the positive and negative electrodes to achieve charging and discharging. 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 edge of the coated positive current collector, serving as the positive electrode tab. Taking a lithium-ion battery as an example, the material of the positive current collector can be aluminum, and the positive active material can be lithium cobalt oxide, lithium iron phosphate, ternary lithium, or lithium manganese oxide, etc. The negative electrode sheet includes a negative electrode current collector and a negative electrode active material layer. The negative electrode active material layer is coated on the surface of the negative electrode current collector. The negative electrode current collector without the negative electrode active material layer protrudes from the edge of the negative electrode current collector with the negative electrode active material layer, and the negative electrode current collector without the negative electrode active material layer serves as the negative electrode tab. The material of the negative electrode current collector can be copper, and the negative electrode active material can be carbon or silicon, etc.

[0039] Please see Figure 2 This application provides a cover plate assembly 100. The cover plate assembly 100 includes a cover plate 101, an electrode post 102, a lower plastic component 103, and a collector plate 10. The electrode post 102 passes through the cover plate 101. One end of the collector plate 10 is connected to the electrode post 102, and the other end is connected to the tab of the electrode assembly 300. The lower plastic component 103 is disposed between the cover plate 101 and the collector plate 10; specifically, the lower plastic component 103 is located between the end of the collector plate 10 connected to the electrode post 102 and the cover plate 101.

[0040] Specifically, the current collector 10 is folded and disposed between the electrode assembly 300 and the cover plate 101. At this time, the lower plastic part 103 is located between the cover plate 101 and the current collector 10 in the folded state. When the current collector 10 is folded, the body 11 and the tail 12 of the current collector 10 are folded together, thereby forming an arc transition zone at the connection between the body 11 and the tail 12. Due to the deformation of the arc transition zone caused by bending, the inner side is compressed and the outer side is stretched. Therefore, under the limiting effect of the material inside the arc transition zone and the rebound effect of the current collector 10, a gap is formed between the body 11 and the tail 12, which can be called the bending gap. The current-carrying component 13 provided in the embodiment of this application is disposed within this bending gap so as not to occupy additional space of the cell 1000, so that the placement of the current-carrying component 13 does not affect the size of the cell 1000.

[0041] It is understood that the cover plate assembly 100 may also include an explosion-proof valve 106, an upper plastic part 104, and a sealing ring. The explosion-proof valve 106 is mounted on the cover plate 101. Additionally, when the pole post 102 is an inverted T-shaped pole post 102, the cover plate assembly 100 may also include a terminal 105. Specifically, the large-diameter end of the pole post 102 is located on the side of the lower plastic part 103 facing away from the cover plate 101, and the small-diameter end of the pole post 102 passes through the lower plastic part 103 and the cover plate 101 in sequence before connecting to the terminal 105. The upper plastic part 104 is disposed between the terminal 105 and the cover plate 101 to insulate and isolate the terminal 105 and the cover plate 101. The sealing ring is ring-shaped on the pole post 102 and located between the pole post 102 and the cover plate 101 to seal the mating part between the cover plate 101 and the pole post 102, preventing electrolyte leakage from this part.

[0042] It is understood that the lower plastic part 103 is used to insulate the cover plate 101 from the internal conductive parts of the battery cell 1000. Specifically, the lower plastic part 103 insulates the cover plate 101 from the large-diameter end of the electrode post 102, the cover plate 101 from the current collector 10, and the cover plate 101 from the electrode assembly 300. At the same time, the cover plate 101 can be axially pressed against the electrode assembly 300 by the lower plastic part 103 to improve the synchronization between the electrode assembly 300 and the housing 200 and prevent the electrode assembly 300 from shaking relative to the housing 200.

[0043] Please see Figure 3 and Figure 4 This application provides a manifold 10. The manifold 10 includes a body 11, a tail portion 12, and a flow-through component 13. One end of the tail portion 12 is connected to one end of the body 11. The flow-through component 13 is connected to the body 11. When the manifold 10 is in an unfolded state, the flow-through component 13 is disposed away from the tail portion 12. The flow-through component 13 is configured to contact the tail portion 12 when the manifold 10 is in a bent state.

[0044] It is understood that the disk body 11, the tail section 12, and the current-carrying component 13 are all conductive structures. For example, when the current collector 10 is connected to the positive electrode tab of the battery cell 1000, and the positive electrode tab is made of aluminum foil, the disk body 11, the tail section 12, and the current-carrying component 13 are all made of aluminum. As another example, when the current collector 10 is connected to the negative electrode tab of the battery cell 1000, and the negative electrode tab is made of copper foil, the disk body 11, the tail section 12, and the current-carrying component 13 are all made of copper.

[0045] It is understood that the disk body 11 and the tail 12 are integrally set so that when the collector disk 10 is in the unfolded state, the disk body 11 and the tail 12 are respectively welded to the electrode assembly 300 and the pole post 102. After the welding is completed, the collector disk 10 can be folded and set between the pole post 102 and the electrode assembly 300 by bending the collector disk 10.

[0046] For example, the manifold 10 is bent once to be folded between the pole post 102 and the electrode assembly 300. In this case, the side view of the manifold 10 can be U-shaped (or C-shaped).

[0047] For example, the collector plate 10 is bent twice to fold between the electrode post 102 and the electrode assembly 300. In this case, the side view of the collector plate 10 can be Z-shaped, such as... Figure 4 As shown.

[0048] It is understandable that the flow-through component 13 can be integrally set with the disk body 11 or welded to the disk body 11.

[0049] In this embodiment, by providing a current-carrying component 13 and ensuring that it contacts the tail portion 12 when the current collector 10 is bent, the current-carrying component 13 can be arranged within the bending gap of the bent current collector 10 to control its height and avoid affecting the height of the battery cell 1000. Furthermore, the current collector 10 can carry current not only through the connection between the plate body 11 and the tail portion 12, but also through the contact between the current-carrying component 13 and the tail portion 12. This not only increases the current-carrying area between the plate body 11 and the tail portion 12, thus improving the current-carrying capacity of the current collector 10, but also allows some current to bypass the connection between the plate body 11 and the tail portion 12 and flow directly through the current-carrying component 13, shortening the current-carrying path between the plate body 11 and the tail portion 12. This reduces the resistance of the current collector 10, thereby reducing the Joule heat generated by the cell 1000 during charging and discharging, which in turn helps to improve the overcurrent capacity and charging and discharging efficiency of the cell 1000.

[0050] Furthermore, by positioning the flow-through component 13 on the side of the disk body 11 away from the tail 12, the flow-through component 13 can contact the tail 12, thereby supporting and limiting the end of the disk body 11 away from the tail 12. This helps maintain the positional stability of the disk body 11 relative to the tail 12 and improves the mechanical stability of the current collector 10 in the folded state. This also ensures sufficient contact force between the end of the disk body 11 away from the tail 12 and the electrode assembly 300, improving the reliability of the connection between the end of the disk body 11 away from the tail 12 and the electrode assembly 300, thus enhancing the reliability of the current flow between the disk body 11 and the electrode assembly 300.

[0051] Please see Figure 5 In some embodiments, when the collector plate 10 is in the deployed state, the collector plate 10 has a length direction. Along this length direction, the plate body 11 has a width dimension D, and the flow passage 13 has a width dimension B, satisfying: 3mm≤B≤50%D.

[0052] Taking a 4680 cylindrical battery cell 1000 (diameter 46mm, length 80mm) as an example, the diameter φd of the disk 11 is 45mm, and the width D of the disk 11 is 36mm. Correspondingly, the width B of the current-carrying component 13 includes, but is not limited to, 9%D, 10%D, 11%D, 12%D, 13%D, 14%D, 15%D, 16%D, 17%D, 18%D, 19%D, 20%D, 21%D, 22%D, 23%D, 24%D, 25%D, 26%D, 27%D, 28%D, 29%D, 30%D, 31%D, ​​32%D, 33%D, 34%D, 35%D, 36%D, 37%D, and 50%D.

[0053] In this embodiment, the above-mentioned limitations can prevent the width dimension B of the flow-through component 13 from being too small, which would be detrimental to molding, and can also prevent the width dimension B of the flow-through component 13 from being too large, which would affect the welding of the collector plate 10 and the electrode tab.

[0054] Please see Figure 5 In some embodiments, the diameter of the disk 11 is φd. The collector disk 10 has a width direction. Along the width direction, the flow passage 13 has a length dimension A, satisfying: 5mm≤A≤35%φd. The width direction is perpendicular to the length direction of the collector disk 10 and parallel to the plane where the disk 11 is located.

[0055] Taking a 4680 cylindrical battery cell 1000 (diameter 46mm, length 80mm) as an example, the diameter φd of the disk 11 is 45mm, and the length dimension A of the current-carrying component 13 includes, but is not limited to, 12%φd, 12.6%φd, 13.2%φd, 13.8%φd, 14.4%φd, 15%φd, 15.6%φd, 16.2%φd, 16.8%φd, 17.4%φd, 18%φd, 18 .6%φd, 19.2%φd, 19.8%φd, 20.4%φd, 21%φd, 21.6%φd, 22.2%φd, 22.8%φd, 23.4%φd, 24%φd, 2 4.6%φd, 25.2%φd, 25.8%φd, 26.4%φd, 27%φd, 27.6%φd, 28.2%φd, 28.8%φd, 29.4%φd, 30%φd.

[0056] In this embodiment, the above-mentioned limitations can prevent the length dimension A of the flow-through component 13 from being too small, which would be detrimental to molding, and can also prevent the length dimension A of the flow-through component 13 from being too large, which would affect the welding of the collector plate 10 and the electrode tab.

[0057] Please see Figure 4 In some embodiments, the distance between the end of the flow element 13 away from the disk body 11 and the disk body 11 is δH, which satisfies: 0.5mm≤δH≤5mm.

[0058] It is understood that the spacing δH includes, but is not limited to, 0.5mm, 0.7mm, 0.9mm, 1mm, 1.1mm, 1.2mm, 1.3mm, 1.5mm, 1.7mm, 1.9mm, 2mm, 2.1mm, 2.2mm, 2.3mm, 2.5mm, 2.7mm, 2.9mm, 3mm, 3.1mm, 3.3mm, 3.5mm, 3.7mm, 3.9mm, 4mm, 4.1mm, 4.3mm, 4.5mm, 4.7mm, 4.9mm, and 5mm.

[0059] In this embodiment, by limiting the spacing δH, on the one hand, it can ensure that the current-carrying component 13 has sufficient height to contact the tail 12 and achieve current stability between the current-carrying component 13 and the tail 12; on the other hand, it can avoid the current-carrying component 13 from having too large a height and occupying too much space inside the cell 1000, thereby helping to ensure that the cell 1000 has a high energy density.

[0060] It is understandable that the larger the gap formed by bending between the disc body 11 and the tail 12, the larger the gap δH.

[0061] In some embodiments, when projected onto a plane parallel to the disk body 11, the projected area of ​​the flow element 13 away from the surface of the disk body 11 is S1, and the area enclosed by the projection of the outer edge line of the end where the flow element 13 connects to the disk body 11 is S2, satisfying: S1 < S2. This allows the flow element 13 to present a structure similar to a cone or stepped shape that is "narrower at the top and wider at the bottom," thereby reducing the stress at the connection between the flow element 13 and the disk body 11, improving the stress state at the connection between the flow element and the disk body 11, and thus enhancing the structural reliability of the collector disk 10.

[0062] Please see Figure 6 In some embodiments, the surface of the flow-through component 13 facing away from the disk body 11 is a first surface 131, and the outer surface of the flow-through component 13 located between the first surface 131 and the disk body 11 is a first circumferential surface 132. A chamfer 133 is provided at the connection between the first surface 131 and the first circumferential surface 132. This ensures that the projected area S2 of the end of the flow-through component 13 connected to the disk body 11 is larger than the projected area S1 of the surface of the flow-through component 13 facing away from the disk body 11, while also making the structure of the flow-through component 13 simple and easy to mold.

[0063] Please see Figure 6 In some embodiments, the surface of the flow-through component 13 facing away from the disk body 11 is a first surface 131, and the outer surface of the flow-through component 13 located between the first surface 131 and the disk body 11 is a first circumferential surface 132. A chamfer 133 is provided at the connection between the first circumferential surface 132 and the disk body 11. This ensures that the projected area S2 of the end of the flow-through component 13 connected to the disk body 11 is larger than the projected area S1 of the surface of the flow-through component 13 facing away from the disk body 11, while also making the structure of the flow-through component 13 simple and easy to mold.

[0064] In some embodiments, the projected area of ​​the flow element 13 away from the surface of the disk body 11 in a plane parallel to the disk body 11 is S1, and the area enclosed by the projection of the outer edge line of the disk body 11 is S, satisfying: 15mm 2 ≤S1≤70%S. In this way, the surface of the flow element 13 facing away from the disk body 11 can have a suitable contact area with the tail 12 to ensure the flow capacity between the flow element 13 and the tail 12, while avoiding the surface area of ​​the flow element 13 facing away from the disk body 11 being too large, which would affect the setting of other structures on the disk body 11.

[0065] Please see Figure 3 In some embodiments, the disk body 11 is provided with a core positioning structure 111. When the collector disk 10 is in the unfolded state, the flow passage 13 is located on the side of the core positioning structure 111 away from the tail 12.

[0066] It is understood that the core positioning structure 111 can be a convex structure, a concave structure, or a through hole. When welding the disk body 11 to the electrode assembly 300, the core positioning structure 111 is used to position the disk body 11 and the electrode assembly 300 to ensure the relative positional accuracy between the disk body 11 and the electrode assembly 300, thereby improving the assembly accuracy of the battery cell 1000 and enhancing the parameter consistency of each battery cell 1000.

[0067] For example, the core positioning structure 111 is a through hole, and the through hole is coaxially arranged with the disc body 11.

[0068] Please see Figure 7 In some embodiments, a groove 112 is provided on the side of the disk 11 facing away from the current-carrying element 13. The groove 112 is disposed opposite to the current-carrying element 13, and the end of the groove 112 away from the slot opening is disposed inside the current-carrying element 13. In this way, the current-carrying element 13 can have a larger contact area with the tail 12, and the material used in the current-carrying disk 10 can be reduced to reduce the weight of the current-carrying disk 10, thereby helping to improve the energy density of the battery cell 1000.

[0069] In addition, the above settings can increase the surface area of ​​the current collector 10, thereby increasing the heat dissipation area of ​​the current collector 10 and improving the heat dissipation efficiency of the battery cell 1000.

[0070] In some embodiments, the thickness of the current-carrying element 13 is less than the thickness of the disk body 11. This shortens the heat conduction path of the current-carrying element 13, improves the efficiency of the current-carrying element 13, thereby improving the heat dissipation efficiency of the current collector disk 10, and thus improving the heat dissipation efficiency of the battery cell 1000.

[0071] Please see Figure 7 In some embodiments, the flow-through element 13 is integrally formed with the disk body 11. This reduces the number of connection points of the collector disk 10, thereby reducing stress concentration at the connection between the flow-through element 13 and the disk body 11, which helps to improve the reliability of the connection between the flow-through element 13 and the disk body 11.

[0072] Please see Figure 7 In some embodiments, the disk body 11 protrudes outward on the side opposite to the flow passage member 13, forming a first recess 113 on the side of the disk body 11 near the flow passage member 13, and a first protrusion 114 on the side of the disk body 11 opposite to the flow passage member 13. The first recess 113 is located near the flow passage member 13.

[0073] When the current collector 10 is applied to the battery cell 1000, it contacts the tail portion 12 via the current-passing element 13, causing the disk body 11 to be subjected to pressure pointing towards the electrode assembly 300 at the current-passing element 13. Simultaneously, the first protrusion 114 abuts against the electrode assembly 300, causing the disk body 11 to be subjected to pressure pointing towards the cover plate 101 at the first protrusion 114. This creates a torque on the disk body 11 with its torsional center located between the first protrusion 114 and the current-passing element 13, increasing the elasticity of the current collector 10 and thus increasing its compression. In this way, while reducing the internal space occupied by the current collector 10 in the battery cell 1000, it also increases the contact force between the current-passing element 13 and the tail portion 12, as well as the contact force between the first protrusion 114 and the electrode assembly 300, thereby improving the current-passing reliability of the current collector 10.

[0074] Please see Figure 4 In some embodiments, the tail portion 12 includes a first sub-portion 121 and a second sub-portion 122. The second sub-portion 122 connects the first sub-portion 121 and the disk body 11. When the collector disk 10 is in a bent state, the second sub-portion 122 is folded between the first sub-portion 121 and the disk body 11. This increases the elasticity of the collector disk 10 in the bent state, thereby increasing the compression of the collector disk 10, allowing it to maintain stable contact with the electrode post 102 and the electrode assembly 300, thus improving the reliability of the connection between the collector disk 10 and the electrode post 102 and the electrode assembly 300.

[0075] It is understandable that the bending direction between the second sub-part 122 and the disk body 11 is opposite to the bending direction between the second sub-part 122 and the first sub-part 121.

[0076] In addition, the above settings can also make the current collector 10 have a longer length in the unfolded state, so as to reduce the mutual interference between the welding of the current collector 10 and the electrode post 102 and the welding of the current collector 10 and the electrode assembly 300, thereby improving the reliability of the cell 1000.

[0077] In order to shorten the flow path, when the collector plate 10 is in the unfolded state, the flow element 13 can be set away from the tail 12 so that the flow element 13 is set closer to the pole 102 in the flow path.

[0078] Please see Figure 5In some embodiments, when the collector plate 10 is in its unfolded state, the collector plate 10 has a length direction. Along the length direction, the second sub-part 122 has a length dimension C, and the flow passage member 13 has a width dimension B, satisfying: 3mm ≤ B ≤ 70% C. This avoids the flow passage member 13 having an excessively small width dimension B, which would be detrimental to molding, and also avoids the flow passage member 13 having an excessively large width dimension B, which would affect the structural design of the collector plate 10. This simplifies the molding process of the collector plate 10 and makes it easy to manufacture.

[0079] Please see Figure 5 In some embodiments, when the collector plate 10 is in its unfolded state, the collector plate 10 has a length direction. A tab welding area 115 is provided on both sides of the plate body 11 along the length direction. The flow-through element 13 is located between the tab welding areas 115. This allows the collector plate 10 to have a large tab welding area 115 while preventing the flow-through element 13 from interfering with the welding between the collector plate 10 and the tabs.

[0080] Please see Figures 3 to 7 In some embodiments, the disc 11 protrudes outward on the side opposite to the flow element 13 to form a protruding tab welding area 115 on the side of the disc 11 opposite to the flow element 13, and a second recess 116 is formed on the side of the disc 11 close to the flow element 13. This allows for a gap between the disc 11 and the electrode assembly 300, facilitating electrolyte flow and improving the wetting efficiency of the electrode assembly 300. For example, the first recess 113 is connected to the second recess 116, and the surface of the first protrusion 114 facing away from the disc body 11 is coplanar with the tab welding area 115.

[0081] Please see Figure 5 In some embodiments, there are two tab welding areas 115, which are symmetrically distributed about the center of the disk body 11. This improves the structural symmetry of the current collector 10, thereby improving the uniformity of stress on the current collector 10 and thus enhancing the reliability of the battery cell 1000.

[0082] Please see Figure 3 In some embodiments, the disc body 11 is provided with a pressure relief port 117. In this way, the high-pressure fluid in the battery cell 1000 can quickly flow into the explosion-proof valve 106 of the battery cell 1000 through the pressure relief port 117, so that the explosion-proof valve 106 can be opened quickly to release air and pressure, and ensure the reliability of the battery cell 1000.

[0083] Please see Figure 3In some embodiments, a through groove 118 is provided at the bending portion of the collector plate 10. The through groove 118 extends along the center line of the bend. When the collector plate 10 is in a bent state, the through groove 118 is located on the concave surface of the collector plate 10. In this way, the obstruction of bending at the concave surface of the collector plate 10 can be reduced when the collector plate 10 is bent, thereby improving the smoothness of bending of the collector plate 10.

[0084] Specifically, the through groove 118 is provided at the connection between the second sub-part 122 and the disk body 11, and at the connection between the second sub-part 122 and the first sub-part 121. The through groove 118 at the connection between the second sub-part 122 and the disk body 11 is located on the side of the disk body 11 closer to the flow-through member 13, while the through groove 118 between the second sub-part 122 and the first sub-part 121 is located on the side of the second sub-part 122 away from the flow-through member 13.

[0085] Please see Figure 8 In some embodiments, a slot 123 is provided on the tail portion 12. When the collector plate 10 is bent, a portion of the flow-through component 13 extends into the slot 123 and is press-fitted with the slot 123, with the end of the flow-through component 13 away from the plate body 11 contacting the bottom surface of the slot 123. This increases the contact area between the flow-through component 13 and the tail portion 12, thereby improving their flow capacity. Furthermore, the press-fit between the flow-through component 13 and the slot 123 prevents the plate body 11 from springing back relative to the tail portion 12 after the collector plate 10 is bent, thus improving the stability of the collector plate 10 in the bent state.

[0086] Specifically, a protrusion 124 is provided on the side of the second sub-part 122 opposite to the slot 123, and the protrusion 124 and the slot 123 are arranged opposite to each other along the thickness direction of the second sub-part 122. When the collector plate 10 is in a bent state, the protrusion 124 contacts the first sub-part 121. In this way, the flow area between the first sub-part 121 and the second sub-part 122 can be increased, thereby improving the flow capacity of the collector plate 10.

[0087] For example, the bottom of the slot 123 is disposed within the protrusion 124, thereby increasing the depth of the slot 123 and increasing the mating area between the slot 123 and the flow member 13, thereby increasing the contact area between the flow member 13 and the tail 12, which helps to improve the flow capacity between them.

[0088] The embodiments of this application have been described in detail above. Specific examples have been used to illustrate the principles and implementation methods of this application. The description of the above embodiments is only for the purpose of helping to understand the method and core ideas of this application. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the ideas of this application. Therefore, the content of this specification should not be construed as a limitation of this application.

Claims

1. A collector disk (10), characterized in that, include: Disk body (11); The tail (12) is connected at one end to one end of the disc body (11); as well as A flow-through component (13) is connected to the disk body (11). When the flow-collecting disk (10) is in the unfolded state, the flow-through component (13) is disposed away from the tail (12). The flow-through component (13) is configured to contact the tail (12) when the flow-collecting disk (10) is in the bent state.

2. The collector disk (10) according to claim 1, characterized in that, When the collector plate (10) is in the unfolded state, the collector plate (10) has a length direction, and along the length direction, the plate body (11) has a width dimension D, and the flow passage component (13) has a width dimension B, satisfying: 3mm≤B≤50%D.

3. The collector disk (10) according to claim 1, characterized in that, The diameter of the disk body (11) is φd, the collector disk (10) has a width direction, and along the width direction, the flow passage (13) has a length dimension A, satisfying: 5mm≤A≤35%φd; The width direction is perpendicular to the length direction of the collector disk (10) and parallel to the plane where the disk body (11) is located.

4. The collector disk (10) according to claim 1, characterized in that, The distance between the end of the flow-through component (13) away from the disk body (11) and the disk body (11) is δH, which satisfies: 0.5mm≤δH≤5mm.

5. The collector disk (10) according to any one of claims 1-4, characterized in that, Projected in a plane parallel to the disk body (11), the projected area of ​​the flow-through component (13) away from the surface of the disk body (11) is S1, and the area enclosed by the projection of the outer edge line of the end of the flow-through component (13) connected to the disk body (11) is S2, satisfying: S1 < S2.

6. The collector disk (10) according to claim 5, characterized in that, The surface of the flow-through component (13) facing away from the disk body (11) is the first surface (131), and the outer surface of the flow-through component (13) located between the first surface (131) and the disk body (11) is the first circumferential surface (132). A chamfer (133) is provided at the connection between the first surface (131) and the first circumferential surface (132); And / or, a chamfer (133) is provided at the connection between the first circumferential surface (132) and the disk body (11).

7. The collector disk (10) according to any one of claims 1-4, characterized in that, Projected onto a plane parallel to the disk body (11), the projected area of ​​the flow-through component (13) away from the surface of the disk body (11) is S1, and the area enclosed by the projection of the outer edge line of the disk body (11) is S, satisfying: 15mm 2 ≤S1≤70%S; And / or, the disk body (11) is provided with a core positioning structure (111), and when the collector disk (10) is in the unfolded state, the flow passage element (13) is located on the side of the core positioning structure (111) away from the tail (12).

8. The collector disk (10) according to any one of claims 1-4, characterized in that, A groove (112) is provided on the side of the disk body (11) away from the flow-through component (13). The groove (112) is disposed opposite to the flow-through component (13), and the end of the groove (112) away from the slot is disposed inside the flow-through component (13).

9. The collector disk (10) according to claim 8, characterized in that, The thickness of the flow-through component (13) is less than the thickness of the disk body (11); And / or, the flow-through component (13) is integrally formed with the disk body (11).

10. The collector disk (10) according to claim 8, characterized in that, The disc body (11) protrudes outward on the side away from the flow member (13) to form a first recess (113) on the side of the disc body (11) close to the flow member (13) and a first protrusion (114) on the side of the disc body (11) away from the flow member (13). The first recess (113) is located near the flow member (13).

11. The collector disk (10) according to any one of claims 1-4, characterized in that, The tail portion (12) includes a first sub-part (121) and a second sub-part (122), the second sub-part (122) connecting the first sub-part (121) and the disc body (11); When the collector plate (10) is in a bent state, the second sub-part (122) is folded between the first sub-part (121) and the plate body (11).

12. The collector disk (10) according to claim 11, characterized in that, When the collector plate (10) is in the unfolded state, the collector plate (10) has a length direction, along the length direction, the second sub-part (122) has a length dimension C, and the flow passage member (13) has a width dimension B, satisfying: 3mm≤B≤70%C.

13. The collector disk (10) according to any one of claims 1-4, characterized in that, When the collector plate (10) is in the unfolded state, the collector plate (10) has a length direction, and electrode welding areas (115) are provided on both sides of the plate body (11) located in the length direction. The flow-through component (13) is located between the electrode welding areas (115).

14. The collector disk (10) according to claim 13, characterized in that, The disc body (11) protrudes outward on the side away from the flow element (13) to form a protruding tab welding area (115) on the side of the disc body (11) away from the flow element (13), and a second recess (116) is formed on the side of the disc body (11) close to the flow element (13). And / or, there are two electrode welding areas (115), and the two electrode welding areas (115) are symmetrically distributed about the center of the disk body (11).

15. The collector disk (10) according to any one of claims 1-4, characterized in that, The disc body (11) is provided with a pressure relief port (117); And / or, a through groove (118) is provided at the bent part of the collector plate (10), the through groove (118) extends along the center line of the bend, and the through groove (118) is located on the concave surface of the collector plate (10) when the collector plate (10) is in a bent state.

16. A cover plate assembly (100), characterized in that, include: Cover plate (101); The pole post (102) is inserted through the cover plate (101); The collector plate (10) as described in any one of claims 1-15, wherein the end of the tail portion (12) away from the plate body (11) is connected to the pole post (102); and The lower plastic part (103) is disposed between the cover plate (101) and the manifold (10).

17. A battery cell (1000), characterized in that, include: Casing (200); An electrode assembly (300) is disposed within the housing (200); as well as The cover plate assembly (100) as claimed in claim 16, wherein the cover plate (101) covers the housing (200), the disk (11) is connected to the electrode assembly (300), and the collector disk (10) is folded between the electrode assembly (300) and the cover plate (101).

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