Cylindrical battery monomer, assembly method and battery device

Abstract

The invention discloses a cylindrical battery monomer, an assembly method and a battery device, and relates to the technical field of batteries, the cylindrical battery monomer comprises a roll core, a shell and a cover plate, the roll core comprises a positive pole lug and a negative pole lug; the shell forms a containing cavity with an opening, and the containing cavity is used for containing the roll core; the cover plate covers the opening of the shell so as to seal the accommodating cavity, and the cover plate is provided with a negative current collecting disc connected with the negative tab; wherein the shell comprises a bottom wall opposite to the opening, the outer surface of the bottom wall is provided with a sinking groove which is sunken towards the direction of the accommodating cavity, one side of the bottom of the sinking groove is welded with the positive pole lug, and the other side of the bottom of the sinking groove is provided with a reinforcing rib. The cylindrical battery monomer is simple in structure, the volume utilization rate can be increased, the energy density can be increased, and the heat dissipation performance of the cylindrical battery monomer can also be improved.

Description

Technical Field

[0001] This invention relates to the field of battery technology, specifically to a cylindrical battery cell and its assembly method, and a battery device. Background Technology

[0002] Energy conservation and emission reduction are key to sustainable social development. Rechargeable batteries, with their ability to store and release energy as needed, are widely used in various electrical devices and energy storage systems, and are an important component in promoting energy transition and sustainable development. For the new energy industry, battery technology is a crucial factor in its development.

[0003] Currently, the positive electrode tabs of the coil are laser-welded to the positive current collector, and the negative electrode tabs are laser-welded to the negative current collector. The cover plate is then welded to the casing. This results in a complex overall structure, low utilization of the internal space of the casing, and limited heat dissipation performance of the coil. Therefore, current cylindrical battery cells suffer from technical problems such as complex structure, low volume utilization, and poor heat dissipation performance. Summary of the Invention

[0004] The purpose of this invention is to overcome the above-mentioned technical deficiencies and propose a cylindrical battery cell and its assembly method and battery device, thereby solving the technical problems of complex structure, low volume utilization and poor heat dissipation performance in the prior art.

[0005] To achieve the above-mentioned technical objectives, the present invention adopts the following technical solution: In a first aspect, the present invention provides a cylindrical battery cell comprising a core, a housing, and a cover plate. The core includes a positive electrode tab and a negative electrode tab. The housing forms a receiving cavity with an opening for receiving the core. The cover plate closes to the opening of the housing to seal the receiving cavity. The cover plate is provided with a negative electrode current collector connected to the negative electrode tab. The housing includes a bottom wall facing the opening. The outer surface of the bottom wall has a groove recessed towards the receiving cavity. One side of the bottom of the groove is welded to the positive electrode tab, and the other side of the bottom of the groove is provided with a reinforcing rib.

[0006] In some embodiments, the projected area of ​​the positive electrode tab on the bottom wall is greater than or equal to the projected area of ​​the bottom of the settling tank on the bottom wall.

[0007] In some embodiments, the reinforcing ribs include radial reinforcing ribs and circumferential reinforcing ribs, with the two ends of the circumferential reinforcing ribs respectively connected to two adjacent radial reinforcing ribs.

[0008] In some embodiments, there are multiple circumferential stiffeners, and some of the circumferential stiffeners are at different distances from the geometric center point of the bottom wall, with the circumferential stiffeners at different distances being arranged in an alternating pattern.

[0009] In some embodiments, the shape of the reinforcing rib projected onto the cross-section is any one or more of square, elliptical, and trapezoidal, and the cross-section is perpendicular to the extension direction of the reinforcing rib.

[0010] In some embodiments, the shape of the reinforcing rib projected on the cross-section is trapezoidal, the length of the upper base of the trapezoid is smaller than the length of the lower base of the trapezoid, and the upper base of the trapezoid is connected to the bottom wall, or the lower base of the trapezoid is connected to the bottom wall.

[0011] In some embodiments, the negative current collector is a flat plate structure, and the base metal of the negative current collector is copper plated with nickel or copper.

[0012] In some embodiments, the negative current collector has a negative current collector center hole that is directly opposite to the center hole of the core. The negative current collector center hole is provided with a flange structure, and the outer diameter of the flange structure is smaller than the diameter of the center hole of the core.

[0013] Secondly, the present invention also provides an assembly method for a cylindrical battery cell. The assembly method is used to assemble the above-mentioned cylindrical battery cell. The assembly method includes welding the negative electrode tab of the core to the negative electrode current collector of the cover plate; inserting the core into the housing such that the positive electrode tab of the core abuts against one side of the bottom of the sinker; welding the positive electrode tab of the core to the bottom of the sinker; and welding the cover plate to the housing.

[0014] Thirdly, the present invention also provides a battery device comprising the aforementioned cylindrical battery cell.

[0015] Compared with existing technologies, the cylindrical battery cell provided by this invention, through a combination of grooves and reinforcing ribs on the bottom wall of the casing, effectively reduces the overall weight of the casing while ensuring structural strength. Simultaneously, by directly connecting the positive electrode tab of the winding core to the bottom of the groove, the need for an additional positive electrode current collector is eliminated. This not only reduces the number of components and simplifies the overall structure of the cylindrical battery cell, but also shortens the heat conduction path, allowing the heat generated during winding core operation to dissipate rapidly through the casing, significantly improving heat dissipation efficiency and thus optimizing the overall performance of the battery. Furthermore, eliminating the positive electrode current collector reduces the internal space occupied by the casing, allowing for the adaptation of larger winding cores within the same casing volume, improving the volume utilization rate of the winding cores; and enabling the mounting of larger winding cores with the same battery weight, effectively increasing the energy density of the battery. Attached Figure Description

[0016] Figure 1 This is a cross-sectional view of a cylindrical battery cell provided in an embodiment of the present invention; Figure 2 This is a schematic diagram of the structure of a cylindrical battery cell provided in an embodiment of the present invention; Figure 3 This is an exploded structural diagram of a cylindrical battery cell provided in an embodiment of the present invention; Figure 4 This is a schematic diagram of the structure of the first type of bottom wall provided in an embodiment of the present invention; Figure 5 This is a schematic diagram of the structure of the second type of bottom wall provided in an embodiment of the present invention; Figure 6 This is a schematic diagram of the third type of bottom wall structure provided in the embodiments of the present invention; Figure 7 This is a schematic diagram of the third type of bottom wall facing the side wall of the receiving cavity provided in the embodiment of the present invention; Figure 8 This is an exploded structural diagram of a cover plate provided in an embodiment of the present invention; Figure 9 This is a schematic flowchart of the cylindrical battery cell assembly method provided in an embodiment of the present invention.

[0017] Explanation of reference numerals in the attached figures: 100. Cylindrical battery cell; 110. Core; 111. Positive electrode tab; 112. Negative electrode tab; 113. Core center hole; 120. Shell; 121. Receiving cavity; 122. Bottom wall; 123. Bottom of settling tank; 130. Cover plate; 131. Negative electrode current collector; 132. Flanged structure; 133. Center hole of negative electrode current collector; 140. Stiffener; 141. Radial stiffener; 142. Circumferential stiffener; 1421. First circumferential stiffener; 1422. Second circumferential stiffener; 150. Welding trajectory; 200. Assembly method. Detailed Implementation

[0018] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0019] Rechargeable batteries have the ability to store or release energy as needed, and are therefore widely used in various electrical devices or energy storage systems.

[0020] In some embodiments, the positive electrode tab of the core is laser-welded to the positive current collector, and the negative electrode tab of the core is laser-welded to the negative current collector. Subsequently, the cover plate is welded to the housing. The overall structure is complex, and the internal space utilization of the housing is not high, resulting in limited heat dissipation performance of the core.

[0021] To address the technical problems of complex structure, low volume utilization, and poor heat dissipation performance in existing technologies, this invention provides a cylindrical battery cell with a simple structure that can improve volume utilization, increase energy density, and enhance heat dissipation performance.

[0022] It should be noted that the cylindrical battery cells of the present invention are used in, but not limited to, electrical devices (such as vehicles). For ease of explanation, this invention will only use the application of cylindrical battery cells in vehicles as an example. The principle of applying cylindrical battery cells to other types of devices (such as energy storage devices) is essentially the same as that of applying them to electrical devices, and will not be described in detail here.

[0023] This application provides a cylindrical battery cell 100, such as... Figures 1 to 5 As shown, the cylindrical battery cell 100 includes a core 110, a housing 120, and a cover plate 130. The core 110 includes a positive electrode tab 111 and a negative electrode tab 112. The housing 120 forms a receiving cavity 121 with an opening for receiving the core 110. The cover plate 130 covers the opening of the housing 120 to close the receiving cavity 121. The cover plate 130 is provided with a negative electrode current collector 131 connected to the negative electrode tab 112. The housing 120 includes a bottom wall 122 facing the opening. The outer surface of the bottom wall 122 has a recessed groove in the direction of the receiving cavity. One side of the bottom 123 of the groove is welded to the positive electrode tab 111, and the other side of the bottom 123 of the groove is provided with a reinforcing rib 140.

[0024] The cylindrical battery cell 100 includes a core 110, a casing 120, a cover plate 130, and other functional components.

[0025] The core 110 is the component in the cylindrical battery cell 100 where the electrochemical reaction occurs. The core 110 is mainly formed by winding positive and negative electrode sheets, and a separator is typically provided between the positive and negative electrode sheets. The portions of the positive and negative electrode sheets containing active material constitute the main body of the core 110, while the portions without active material each constitute electrode tabs. The positive and negative electrode tabs are located at opposite ends of the main body. During the charging and discharging process of the battery, the positive and negative active materials react with the electrolyte. The positive electrode tab 111 connects to the casing 120, and the negative electrode tab 112 connects to the negative current collector 131 to form a current loop.

[0026] The housing 120 is an assembly used to cooperate with the cover plate 130 to form the internal environment of the cylindrical battery cell 100. The housing 120 forms a receiving cavity 121 with an opening, which can be used to accommodate the core 110, electrolyte, and other components. The housing 120 and the cover plate 130 are independent components. The housing 120 has an opening, and the cover plate 130 closes the opening to form the internal environment of the cylindrical battery cell 100. Specifically, the cover plate 130 and the housing 120 can form a common connecting surface before other components are inserted into the housing. When it is necessary to encapsulate the interior of the housing 120, the cover plate 130 closes the housing 120. The housing 120 is cylindrical in shape and can be of various sizes. Specifically, the size of the housing 120 can be determined according to the specific size of the core 110. The housing 120 can be made of various materials, such as copper, iron, aluminum, or aluminum alloy.

[0027] The cover plate 130 refers to a component that covers the opening of the housing 120 to isolate the internal environment of the cylindrical battery cell 100 from the external environment. Optionally, the cover plate 130 can be made of a material with a certain hardness and strength (such as aluminum alloy), so that the cover plate 130 is not easily deformed when subjected to compression and impact, giving the cylindrical battery cell 100 higher structural strength and improving safety performance. Functional components such as a negative electrode current collector 131 can be provided on the cover plate 130. The negative electrode current collector 131 can be used to electrically connect with the negative electrode tab 112 of the winding core 110 for outputting or inputting electrical energy of the cylindrical battery cell 100. The cover plate 130 can also be made of various materials, such as copper, iron, aluminum, stainless steel, aluminum alloy, etc. In some embodiments, the cover plate 130 can also be provided with a pressure relief mechanism for releasing internal pressure when the internal pressure or temperature of the cylindrical battery cell 100 reaches a threshold. In some embodiments, an insulating element may be provided on the inner side of the cover plate 130. The insulating element can be used to isolate the electrical connection components within the housing 120 from the cover plate 130 to reduce the risk of short circuits. Exemplarily, the insulating element may be made of plastic, rubber, etc.

[0028] In this embodiment, the outer surface of the bottom wall 122 has a recessed groove that faces the receiving cavity 121. The depth of the recessed groove can be determined according to actual needs, such as 1mm, 2mm, 3mm, etc. The groove is the through-welding area between the bottom wall 122 of the housing 120 and the positive electrode tab 111. The positive electrode tab 111 is attached to the side of the bottom 123 of the groove facing the receiving cavity 121, and an electrical connection is formed by through welding, so that the housing 120 is positively charged and becomes the positive output terminal. For example, the wall surface of the bottom 123 of the groove facing the receiving cavity 121 is flat, which can improve the contact and attachment effect between the positive electrode tab 111 and the bottom 123 of the groove.

[0029] The countersink can reduce the thickness of the welding area of ​​the shell 120, thereby reducing welding power and the risk of weld burn-through. Simultaneously, the recessed space of the countersink can accommodate slight protrusions caused by through-welds, preventing unevenness of the bottom wall 122. The welding trajectory 150 between the bottom 123 of the countersink and the positive electrode tab 111 is not limited, such as... Figure 4 and Figure 5 As shown, the starting and ending points of the welding trajectory 150 should not exceed the contact surface between the positive electrode tab 111 and the bottom 123 of the sinker in the housing 120 to avoid the risk of weld burn-through. For example, the welding trajectory 150 can be radial in the direction of the bottom 123 of the sinker, radiating outward from the center of the bottom 123 of the sinker, thereby enabling the positive electrode tab 111 of the core 110 to make more electrical connections with the bottom 123 of the sinker in the housing 120 from the inner ring to the outer ring, reducing the migration path of electrons on the core 110, effectively reducing the connection internal resistance between the core 110 and the housing 120, and reducing the heat generated.

[0030] A reinforcing rib 140 is provided on the side of the bottom 123 of the sink that faces away from the receiving cavity 121. The specific shape and number of the reinforcing rib 140 are not limited, as long as they meet the strength loss requirements caused by the sink structure. Furthermore, the reinforcing rib 140 can increase the surface area for heat dissipation, further improving the heat dissipation performance of the battery. Relevant embodiments of the reinforcing rib 140 will be given later, and will not be elaborated here. It should be noted that the setting of the reinforcing rib 140 should not affect the subsequent welding of the bottom 123 of the sink to the positive electrode tab 111.

[0031] In this embodiment, by employing a combination of a recessed groove and reinforcing ribs 140 on the bottom wall 122 of the housing 120, the overall weight of the housing 120 can be effectively reduced while ensuring structural strength. Simultaneously, by directly connecting the positive electrode tab 111 of the winding core 110 to the bottom 123 of the recessed groove, an additional positive electrode current collector is unnecessary. This not only reduces the number of components and simplifies the overall structure of the cylindrical battery cell 100, but also shortens the heat conduction path, allowing the heat generated by the winding core 110 during operation to dissipate quickly through the housing 120. Furthermore, the reinforcing ribs 140 further increase the heat dissipation area, significantly improving heat dissipation efficiency and thus optimizing the overall performance of the battery. In addition, by eliminating the positive electrode current collector, the internal space occupied by the housing 120 is reduced. This allows for the adaptation of a larger volume winding core 110 within the same housing 120 volume, improving the volume utilization rate of the winding core 110; and it also allows for the mounting of a larger mass winding core with the same battery weight, effectively increasing the battery's energy density.

[0032] In some embodiments, the positive electrode tab 111 has a projected area on the bottom wall 122 that is greater than or equal to the projected area of ​​the bottom of the sink 123 on the bottom wall 122.

[0033] In this embodiment, the design ensures that when the bottom 123 of the sink is welded to the positive electrode tab 111, the welding surface completely covers the area of ​​the bottom 123 of the sink, minimizing welding blind spots and poor contact problems, improving the firmness of the connection between the positive electrode tab 111 and the bottom 123 of the sink, reducing contact resistance and the risk of detachment during long-term use; and the fully covered welding surface can also effectively disperse the stress under the action of external forces such as vibration and impact, further enhancing the structural stability of the weld.

[0034] In some embodiments, such as Figure 6 and Figure 7 As shown, the reinforcing rib 140 includes a radial reinforcing rib 141 and a circumferential reinforcing rib 142, with both ends of the circumferential reinforcing rib 142 connected to two adjacent radial reinforcing ribs 141 respectively.

[0035] In this embodiment, the reinforcing ribs 140 adopt a combined radial and circumferential design. The radial reinforcing ribs 141 extend along the radial direction of the bottom wall 122, and the circumferential reinforcing ribs 142 are arranged along the circumference of the bottom wall 122. The two ends of the circumferential reinforcing ribs 142 are fixedly connected to the adjacent radial reinforcing ribs 141. Multiple radial reinforcing ribs 141 and circumferential reinforcing ribs 142 form a mesh-like interwoven structure, which fully covers the recessed area of ​​the bottom 123 of the settling tank. Therefore, by combining the radial reinforcing ribs 141 and circumferential reinforcing ribs 142, the circumferential stiffness of the bottom wall 122 can be improved, effectively enhancing the overall strength and stability of the bottom wall 122. Furthermore, the mesh-like interwoven structure can evenly distribute stress, avoiding local stress concentration that could lead to deformation or damage to the shell 120.

[0036] In some embodiments, such as Figure 6 and Figure 7 As shown, there are multiple circumferential reinforcing ribs 142, and some of the circumferential reinforcing ribs 142 are at different distances from the geometric center point of the bottom wall 122. The circumferential reinforcing ribs 142 at different distances are arranged in an alternating manner.

[0037] In this embodiment, some of the multiple circumferential reinforcing ribs 142 are at different distances from the geometric center point of the bottom wall 122, that is, circumferential reinforcing ribs 142 with different radii are formed, and the circumferential reinforcing ribs 142 with different radii are staggered and arranged in an alternating manner.

[0038] For example, the circumferential reinforcing rib 142 includes a first circumferential reinforcing rib 1421 and a second circumferential reinforcing rib 1422. A plurality of first circumferential reinforcing ribs 1421 form an inner circumferential reinforcing structure, and a plurality of second circumferential reinforcing ribs 1422 form an outer circumferential reinforcing structure. The first circumferential reinforcing ribs 1421 and the second circumferential reinforcing ribs 1422 are arranged alternately along the bottom wall 122 in a circumferential manner.

[0039] In this embodiment, multiple layers of protection are formed by the interlaced circumferential reinforcing ribs 142. On the one hand, this can improve the structural strength. On the other hand, when the circumferential reinforcing ribs 142 may obstruct the welding trajectory 150, they can compensate in the adjacent welding area. This allows the positive electrode tabs 111 of each layer of winding inside and outside the core 110 to make welding contact with the bottom 123 of the sinker of the housing 120, reducing the migration path of electrons on the core 110, reducing the internal resistance of the battery and reducing heat generation.

[0040] In some embodiments, the shape of the reinforcing rib 140 projected onto the cross-section is any one or more of a square, an ellipse, and a trapezoid, and the cross-section is perpendicular to the extending direction of the reinforcing rib 140.

[0041] In this embodiment, the reinforcing rib 140 and the shell 120 can be integrally formed, or the reinforcing rib 140 can be connected to the bottom wall 122 by subsequent welding. For example, the radial reinforcing rib 141 adopts a trapezoidal cross-section, and the circumferential reinforcing rib 142 adopts a square cross-section. By providing various forms of reinforcing rib 140, a suitable structure can be selected according to the actual situation to meet the needs of multiple scenarios.

[0042] In some embodiments, the shape of the reinforcing rib 140 projected on the cross section is a trapezoid, the length of the upper base of the trapezoid is smaller than the length of the lower base of the trapezoid, and the upper base of the trapezoid is connected to the bottom wall 122, or the lower base of the trapezoid is connected to the bottom wall 122.

[0043] It should be noted that the inclined surface of a trapezoidal structure can distribute the force, providing stronger support and resistance to deformation than square or elliptical structures within the same space.

[0044] In this embodiment, the upper bottom of the trapezoidal reinforcing rib 140 is connected to the bottom wall 122. In other words, the smaller top surface of the reinforcing rib 140 is connected to the bottom wall 122, and the larger bottom surface of the reinforcing rib 140 faces outward. When the cylindrical battery cells 100 need to be stacked, the larger bottom surface of the reinforcing rib 140 can provide a larger force-bearing area, thereby improving the stability of the stacking arrangement and increasing the heat dissipation surface area, thus improving heat dissipation efficiency.

[0045] In this embodiment, the bottom of the trapezoidal reinforcing rib 140 is connected to the bottom wall 122. In other words, the bottom surface of the reinforcing rib 140 with a larger area is connected to the bottom wall 122, and the bottom surface of the reinforcing rib 140 with a smaller area faces outward. The connection between the bottom surface with a larger area and the bottom wall 122 can improve the structural strength of the reinforcing rib 140 and the bottom wall 122.

[0046] In some embodiments, such as Figure 8 As shown, the negative current collector 131 has a flat plate structure, and the base metal of the negative current collector 131 is copper plated with nickel or copper.

[0047] In this embodiment, the negative electrode current collector 131 adopts a flat plate structure, which facilitates welding with the negative electrode tab 112. The base metal of the negative electrode current collector 131 is copper-plated nickel or copper, meaning that the main metal of the material of the negative electrode current collector 131 is copper-plated nickel or copper, and it may also contain a small amount of other metals. By adopting a planar structure as a whole, the overall thickness of the negative electrode current collector 131 after bending can be reduced; and the negative electrode current collector 131 is made of copper-plated nickel or pure copper. Under the same conditions, the resistivity of pure copper is about 60% of that of pure aluminum, and its current carrying capacity is stronger than that of aluminum. Therefore, under the same current carrying requirements, the copper current collector can be made thinner, further increasing the usable height of the internal core 110 of the battery, improving the internal volume utilization rate of the battery, and increasing the energy density of the cell.

[0048] In some embodiments, such as Figure 8 As shown, the negative electrode current collector 131 has a negative electrode current collector center hole 133 that is directly opposite to the core center hole 113. The negative electrode current collector center hole 133 is provided with a flange structure 132, and the outer diameter of the flange structure 132 is smaller than the diameter of the core center hole 113.

[0049] In this embodiment, a negative electrode current collector 131 is provided with a negative electrode current collector center hole 133 directly opposite to the core center hole 113, and a flange structure 132 is added to the negative electrode current collector center hole 133, extending towards the core 110. The outer diameter of the flange structure 132 is smaller than the diameter of the core center hole 113, ensuring that the flange structure 132 can extend into the core center hole 113. For example, the outer diameter of the flange structure 132 is 0.1 mm smaller on each side than the diameter of the core center hole 113.

[0050] In this embodiment, the flange structure 132 can increase the bonding strength of the negative electrode current collector 131, prevent deformation, and avoid affecting the welding quality of the negative electrode current collector 131 and the core 110. At the same time, it can play a positioning role when the negative electrode current collector 131 and the negative electrode tab 112 of the core 110 are bonded and welded.

[0051] This application embodiment also provides an assembly method 200 for a cylindrical battery cell, such as... Figure 9 As shown, the assembly method 200 is used to assemble the above-mentioned cylindrical battery cell 100, and the assembly method 200 includes: Step S210: Weld the negative electrode tab 112 of the core 110 to the negative electrode current collector 131 of the cover plate 130.

[0052] Specifically, one side of the negative current collector 131 is welded to the negative electrode tab 112 of the core 110, and the other side of the negative current collector 131 is welded to the pole post, so that the pole post serves as the negative terminal for external output.

[0053] In step S220, the core 110 is inserted into the housing 120, so that the positive electrode tab 111 of the core 110 abuts against one side of the bottom 123 of the sink.

[0054] Specifically, after the negative electrode tab 112 is welded, the positive electrode tab 111 of the core 110 is inserted into the housing 120 with the bottom wall 122 of the housing 120 facing it, and the positive electrode tab 111 and the bottom wall 122 facing the receiving cavity 121 are tightly fitted together.

[0055] In step S230, the positive electrode tab 111 of the core 110 is welded to the bottom 123 of the sinker, and the cover plate 130 is welded to the shell 120.

[0056] Specifically, the bottom 123 of the sinker is electrically connected to the positive electrode tab 111 of the core 110 by laser penetration welding, and then the cover plate 130 is assembled with the opening end of the shell 120 and sealed by peripheral sealing welding.

[0057] In this embodiment, the assembly process is simple and orderly, reducing redundant assembly steps, adapting to mass production, and significantly improving production efficiency.

[0058] This application also provides a battery device, which includes the cylindrical battery cell 100 described above.

[0059] In this embodiment, the battery device includes a housing and cylindrical battery cells 100, with the cylindrical battery cells 100 housed within the housing. The housing can have various structures. In some embodiments, the housing may include a first part and a second part, which overlap each other, together defining a receiving space for accommodating the cylindrical battery cells 100. The second part may be a hollow structure with one open end, and the first part may be a plate-like structure, with the first part covering the open side of the second part so that the first and second parts together define the receiving space; alternatively, both the first and second parts may be hollow structures with one open side, with the open side of the first part covering the open side of the second part. Of course, the housing formed by the first and second parts can be of various shapes, such as a cylinder, a cuboid, etc.

[0060] In this embodiment, the battery device may contain multiple cylindrical battery cells 100, which can be connected in series, parallel, or in a mixed configuration. A mixed configuration means that the multiple cylindrical battery cells 100 are connected in both series and parallel connections. The multiple cylindrical battery cells 100 can be directly connected in series, parallel, or in a mixed configuration, and then the entire assembly of the multiple cylindrical battery cells 100 is housed within a casing. Alternatively, the battery device may consist of multiple cylindrical battery cells 100 first connected in series, parallel, or in a mixed configuration to form battery modules, and then these battery modules are connected in series, parallel, or in a mixed configuration to form a whole, which is then housed within a casing. The battery device may also include other structures; for example, it may include a busbar component for electrical connection between the multiple cylindrical battery cells 100.

[0061] The specific embodiments of the present invention described above do not constitute a limitation on the scope of protection of the present invention. Any other corresponding changes and modifications made in accordance with the technical concept of the present invention should be included within the scope of protection of the claims of the present invention.

Claims

1. A cylindrical battery cell, characterized in that, include: The core includes a positive electrode tab and a negative electrode tab; The housing forms a receiving cavity with an opening for receiving the winding core; as well as A cover plate, which covers the opening of the housing to close the receiving cavity, the cover plate being provided with a negative electrode current collector connected to the negative electrode tab; The housing includes a bottom wall facing the opening, the outer surface of the bottom wall has a recessed groove that is recessed toward the receiving cavity, one side of the bottom of the groove is welded to the positive electrode tab, and the other side of the bottom of the groove is provided with a reinforcing rib.

2. The cylindrical battery cell according to claim 1, characterized in that, The positive electrode tab's projected area on the bottom wall is greater than or equal to the projected area of ​​the bottom of the settling tank on the bottom wall.

3. The cylindrical battery cell according to claim 1 or 2, characterized in that, The reinforcing ribs include radial reinforcing ribs and circumferential reinforcing ribs, and the two ends of the circumferential reinforcing ribs are respectively connected to two adjacent radial reinforcing ribs.

4. The cylindrical battery cell according to claim 3, characterized in that, The number of circumferential reinforcing ribs is multiple, and some of the circumferential reinforcing ribs are at different distances from the geometric center point of the bottom wall, with the circumferential reinforcing ribs at different distances being arranged in an alternating pattern.

5. The cylindrical battery cell according to claim 1, characterized in that, The shape of the reinforcing rib projected onto the cross-section is any one or more of square, elliptical, and trapezoidal, and the cross-section is perpendicular to the extension direction of the reinforcing rib.

6. The cylindrical battery cell according to claim 5, characterized in that, The reinforcing rib is projected into a trapezoidal shape on the cross-section. The length of the upper base of the trapezoid is smaller than the length of the lower base. The upper base of the trapezoid is connected to the bottom wall, or the lower base of the trapezoid is connected to the bottom wall.

7. The cylindrical battery cell according to claim 1, characterized in that, The negative electrode current collector has a flat plate structure, and the base metal of the negative electrode current collector is copper plated with nickel or copper.

8. The cylindrical battery cell according to claim 1, characterized in that, The negative electrode current collector has a negative electrode current collector center hole that is directly opposite the center hole of the core. The center hole of the negative electrode current collector has a flange structure, and the outer diameter of the flange structure is smaller than the diameter of the center hole of the core.

9. A method for assembling a cylindrical battery cell, the method being used to assemble the cylindrical battery cell according to any one of claims 1-8, characterized in that, The assembly method includes: The negative electrode tab of the winding core is welded to the negative electrode current collector of the cover plate; The core is inserted into the housing such that the positive electrode tab of the core abuts against one side of the bottom of the sinker. The positive electrode tab of the winding core is welded to the bottom of the sinker, and the cover plate is welded to the housing.

10. A battery device, characterized in that, Includes the cylindrical battery cell as described in any one of claims 1-8.

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