Single cell and battery pack

Abstract

Embodiments of the present application relate to the technical field of battery, and specifically disclose a single battery and a battery pack, wherein the single battery comprises: a shell having a containing cavity; an electrode assembly arranged in the containing cavity; a first end cover connected to one end of the shell in the axial direction; a pole post penetrating through the first end cover in the axial direction; a first current collecting element comprising: a first current collecting part arranged between the first end cover and the electrode assembly, and a first protruding part protruding from one side of the first current collecting part away from the electrode assembly, wherein the first protruding part penetrates through the pole post in the axial direction, and the first protruding part is provided with a first through hole penetrating through in the axial direction; and a first sealing element arranged in the first through hole and sealing the first through hole, wherein the first sealing element and the first protruding part are both welded to the pole post. According to the present application, the dust generated during welding cannot enter the shell, thereby avoiding the dust generated during welding from entering the shell to cause short circuit of the single battery, and improving the safety performance of the single battery.

Description

Technical Field

[0001] This application relates to the field of battery technology, and in particular to a single cell battery and a battery pack. Background Technology

[0002] The replacement of traditional fuel vehicles with new energy vehicles is of great significance to improving the energy and pollution problems faced by the global transportation industry, and it is also an inevitable trend. Among them, the power battery, as a key component of new energy vehicles, has attracted much attention. The performance of the power battery directly affects the key indicators of new energy vehicles such as driving range, charging time, and safety performance.

[0003] With the rapid development of the new energy industry, secondary batteries with high energy density, long cycle life, and high safety performance have been widely used and developed, and the demand for secondary batteries with larger capacity, greater durability, and enhanced safety is extremely urgent. Safety performance is one of the core performance characteristics of secondary batteries. Therefore, how to improve the safety performance of secondary batteries has become a pressing issue that needs to be addressed. Utility Model Content

[0004] Embodiments of this application provide a single battery cell and a battery pack to improve the safety performance of the single battery cell.

[0005] To address the aforementioned technical problems, embodiments of this application disclose the following technical solutions:

[0006] On one hand, a single-cell battery is provided, having an axial orientation, including: a housing having a receiving cavity;

[0007] Electrode assembly, disposed within the receiving cavity;

[0008] The first end cap connects to one axial end of the housing;

[0009] The pole is axially inserted through the first end cap, and the pole and the first end cap are insulated from each other.

[0010] The first current collector element includes: a first current collector portion and a first protrusion portion. The first current collector portion is disposed between the first end cap and the electrode assembly and is electrically connected to the electrode assembly. The first protrusion portion protrudes from the side of the first current collector portion away from the electrode assembly and passes through the electrode post axially. The first protrusion portion is electrically connected to the electrode post, and the first protrusion portion has a first through hole extending axially.

[0011] The first sealing element is disposed in the first through hole and blocks the first through hole. Both the first sealing element and the first protrusion are welded to the pole post.

[0012] In addition to one or more of the features disclosed above, or as an alternative, the pole post is provided with a second through hole that extends along the axial direction, and the first protrusion is embedded in the second through hole;

[0013] A welding groove is provided on the side of the first seal away from the electrode assembly. The welding groove has a first groove wall extending along the axial direction. The first seal and the first protrusion are welded together to the electrode post from the first groove wall.

[0014] In addition to one or more of the features disclosed above, or as an alternative, the first current collector element further includes: a support portion disposed on the side of the first through hole near the electrode assembly, and the support portion being connected to the hole wall of the first through hole, the side of the support portion opposite to the electrode assembly abutting against the first seal.

[0015] In addition to one or more of the features disclosed above, or as an alternative, the support portion is provided with an axially penetrating injection hole that communicates with the receiving cavity.

[0016] In addition to one or more of the features disclosed above, or as an alternative, the first current collector element further includes: a second protrusion, protruding from the side of the first current collector away from the electrode assembly, and the second protrusion is connected to the outer wall surface of the first protrusion, and the second protrusion and the electrode post are spaced apart in the axial direction.

[0017] In addition to one or more of the features disclosed above, or alternatively, the single cell also has a circumferential orientation around the axial direction;

[0018] The first current collection section includes multiple reinforcing sections and multiple welding sections, with each reinforcing section and each welding section alternately arranged around the outer edge of the second protrusion in the circumferential direction.

[0019] In addition to one or more of the features disclosed above, or alternatively, the single cell also has a radial direction perpendicular to the axial direction;

[0020] Each reinforcing part extends radially, and in the radial direction, along the direction from the first protrusion to the second protrusion, the thickness of each reinforcing part gradually decreases in the axial direction.

[0021] In addition to one or more of the features disclosed above, or as an alternative, the pole post is provided with a second through hole that extends along the axial direction, and the first protrusion is embedded in the second through hole;

[0022] The first seal has an end wall on the side away from the electrode assembly, and the first seal and the first protrusion are welded together to the electrode post from the end wall.

[0023] In addition to one or more of the features disclosed above, or as an alternative, the electrode post has a second through hole extending along the axial direction, and the electrode post has a first fixing groove on the side near the electrode assembly.

[0024] The first protrusion is embedded in the first fixing groove, the side of the first seal away from the electrode assembly is embedded in the second through hole, and the side of the first seal close to the electrode assembly is disposed in the first through hole.

[0025] A welding groove is provided on the side of the first seal away from the electrode assembly. The welding groove has a first groove wall extending along the axial direction. The first seal and the first protrusion are welded together to the electrode post from the first groove wall.

[0026] In addition to one or more of the features disclosed above, or as an alternative, the first fixing groove extends axially and has a second groove wall on the side of the first fixing groove away from the electrode assembly in the axial direction, the first protrusion and the second groove wall are spaced apart in the axial direction, and the pole post and the first current collector are spaced apart in the axial direction.

[0027] In addition to one or more of the features disclosed above, or as an alternative, it also includes: a second end cap disposed on the side of the housing axially away from the first end cap, and the second end cap having a third through hole extending axially.

[0028] A second current collector is disposed in the receiving cavity and between the second end cap and the electrode assembly. The second current collector is electrically connected to both the electrode assembly and the second end cap.

[0029] The second seal is embedded in the third through hole and blocks the third through hole.

[0030] In addition to one or more of the features disclosed above, or as an alternative, the second end cap includes: a cover body portion and a third protrusion portion, the cover body portion being disposed on the side of the housing axially away from the first end cap, the third protrusion portion being protruded on the side of the cover body portion near the electrode assembly, and the third protrusion portion having a third through hole extending axially.

[0031] The second current collector element includes a second current collector portion and a fourth protrusion portion. The second current collector portion is disposed between the second end cap and the electrode assembly, and the second current collector portion is electrically connected to the electrode assembly. The fourth protrusion portion protrudes from the side of the second current collector portion away from the electrode assembly, and a second fixing groove is formed on the side of the fourth protrusion portion away from the second current collector portion. A third protrusion portion is embedded in the second fixing groove, and the third protrusion portion is electrically connected to the fourth protrusion portion.

[0032] In addition to one or more of the features disclosed above, or as an alternative, the third protrusion is spaced apart from the second flow collector in the axial direction, and the fourth protrusion is spaced apart from the cover portion.

[0033] On the other hand, a battery pack is further disclosed, which, in addition to one or more of the features disclosed above, or alternatively, includes a housing; a single cell as described in any of the preceding claims, the single cell being disposed within the housing; and a cover connected to the housing and sealing the housing.

[0034] One of the above technical solutions has the following advantages or beneficial effects: In this application, by welding the first seal and the first protrusion together to the terminal post from the first seal, the terminal post, the first current collector, and the first seal are welded and fixed on the outside of the single battery casing. This prevents dust generated during welding from entering the casing, thus avoiding short circuits caused by dust entering the casing and improving the safety performance of the single battery. Furthermore, this application achieves the welding and fixing of the terminal post, the first current collector, and the first seal through a single welding process, reducing the welding steps during single battery assembly, optimizing the overall assembly production process of the single battery, reducing the overall defect rate of the single battery, and improving the production efficiency of the single battery. At the same time, this application embeds the first seal into the first through hole of the first current collector, forming a bushing fit structure between the first current collector and the first seal. This bushing fit structure eliminates assembly tolerances during the single battery assembly process, ensuring tight assembly and connection of all components in the single battery, thereby ensuring the overall structural stability of the single battery and further improving the safety and reliability of the single battery. Attached Figure Description

[0035] The technical solution and other beneficial effects of this application will become apparent from the following detailed description of specific embodiments in conjunction with the accompanying drawings.

[0036] Figure 1 This is an exploded structural view of a single cell provided according to a specific embodiment of this application;

[0037] Figure 2 This is a front view of a single cell provided according to a specific embodiment of this application;

[0038] Figure 3 This is a cross-sectional view of a single cell along the AA direction according to a specific embodiment of this application;

[0039] Figure 4 yes Figure 3 A magnified view of a section at point C;

[0040] Figure 5 This is a partial exploded cross-sectional view of a single cell along the AA direction provided in a specific embodiment of this application;

[0041] Figure 6 This is a three-dimensional structural view of the first current collector element provided according to a specific embodiment of this application;

[0042] Figure 7 This is a cross-sectional view of a single cell along the AA direction according to a specific embodiment of this application;

[0043] Figure 8 yes Figure 7 A magnified view of a section at point D;

[0044] Figure 9 This is a cross-sectional view of a single cell along the AA direction according to a specific embodiment of this application;

[0045] Figure 10 yes Figure 9 A magnified view of a section at point E in the middle;

[0046] Figure 11 This is a partial exploded cross-sectional view of a single cell along the AA direction provided in Specific Embodiment 3 of this application;

[0047] Figure 12 This is a three-dimensional structural view of the pole provided according to a specific embodiment three of this application;

[0048] Figure 13 This is an exploded structural view of a single cell provided according to specific embodiment four of this application;

[0049] Figure 14 This is a front view of a single cell provided according to specific embodiment four of this application;

[0050] Figure 15 This is a cross-sectional view of a single cell along the BB direction according to a specific embodiment of this application;

[0051] Figure 16 yes Figure 15 A magnified view of a section at point F in the middle;

[0052] Figure 17 This is a partial exploded cross-sectional view of a single cell along the BB direction provided in Specific Embodiment 4 of this application.

[0053] Explanation of reference numerals in the attached figures:

[0054] 100. Single cell; 110. Casing; 111. Receiving cavity; 120. Electrode assembly; 131. First end cap; 132. Second end cap; 1321. Cover portion; 1322. Third protrusion; 1323. Third through hole; 140. Terminal post; 141. Second through hole; 142. First fixing groove; 1421. Second groove wall; 150. First current collector; 151. First current collector portion; 152. First protrusion; 1521. First through hole; 15 3. Support part; 1531. Injection hole; 154. Second protrusion; 155. Reinforcing part; 156. Welding part; 160. First sealing element; 161. Welding groove; 162. First groove wall; 163. End wall; 164. Weld mark; 170. Second current collector element; 171. Second current collector part; 172. Fourth protrusion; 1721. Second fixing groove; 180. Second sealing element; 191. Riveting part; 192. Third sealing element; 193. Insulating part. Detailed Implementation

[0055] To make the objectives, technical solutions, and beneficial effects of this application clearer, the following detailed description, in conjunction with the accompanying drawings and specific embodiments, further illustrates this application. It should be understood that the specific embodiments described in this specification are merely for explaining this application and are not intended to limit it.

[0056] In the description of this application, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," and "counterclockwise," etc., indicating orientation or positional relationships based on the orientation or positional relationships shown in the accompanying drawings, are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application. Furthermore, 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 indicated technical features. Thus, features defined with "first" and "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.

[0057] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "joining" 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, a direct connection, or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0058] In this application, unless otherwise expressly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature being directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature being directly above or diagonally above the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0059] The application of cylindrical secondary batteries in new energy vehicles is a hot topic in the industry. The positive electrode connection in cylindrical secondary batteries mainly uses laser penetration welding between the electrode post and the positive current collector. The negative electrode connection mainly uses laser penetration welding between the top cover and the current collector, or side welding between the current collector and the casing wall. However, both of these connection methods have drawbacks: the existing positive current collector and electrode post are welded inside the casing, and the top cover and current collector are also welded inside the casing. Dust generated during welding can easily fall into the battery, potentially causing internal short circuits and affecting battery safety. Yes; secondly, when both the positive and negative electrodes are laser-through welded, the assembly tolerance requirements are high. If the overall design tolerance absorption capacity is insufficient during battery assembly, it will lead to welding failure or the sealing weld strength will not meet the standard. Moreover, the existing cylindrical battery welding process is complicated. Generally, according to the process flow, it includes six welding processes: negative electrode current collector welding, positive electrode current collector welding, positive electrode penetration welding, negative electrode penetration welding, sealing weld, and sealing nail welding. During the manufacturing process, each welding process will generate a defect rate. The accumulation of defect rates in each process will lead to a high overall product defect rate.

[0060] In the embodiments of this application, reference is made to Figures 1 to 4This application provides a single-cell battery 100, which has an axial direction Z, a circumferential direction R around the axial direction Z, and a radial direction X perpendicular to the axial direction Z. The axial direction Z, radial direction X, and circumferential direction R are mutually perpendicular. It should be noted that in all embodiments of this application, the axial direction Z refers to the direction indicated by the arrow "Z" in the accompanying drawings; it should be understood that the axial direction Z is the direction indicated by the straight line perpendicular to the outer surface of the first end cover 131. A cylindrical coordinate system is constructed with the straight line passing through the center of the first end cover 131 and parallel to the axial direction Z as the axis (which can be regarded as the axis of the first end cover 131). The circumferential direction R refers to the direction of the tangent of the circle with the intersection of the aforementioned axis and the aforementioned plane as the center on the plane perpendicular to the axial direction Z. The radial direction X refers to the direction of the ray starting from the aforementioned axis and in the aforementioned plane. It should be understood that the concepts of axial Z, radial X, and circumferential R are introduced in all embodiments of this application merely for the convenience of describing spatial positional relationships and should not be construed as limiting the scope of the embodiments of this application. Therefore, the fact that axial Z, radial X, and circumferential R are mutually perpendicular can be reasonably interpreted, based on the actual technical scenario, as a nearly perpendicular directional relationship between each pair of axial Z, radial X, and circumferential R. For example, the included angle between each pair of axial Z, radial X, and circumferential R is in the range of 85°-95°. As long as the technical solution conforms to the spirit of this application or achieves the technical effect described in this application, it can be considered to fall within the scope defined by the appended claims.

[0061] Specifically, refer to Figures 1 to 5 The single cell 100 includes: a housing 110, an electrode assembly 120, a first end cap 131, a terminal post 140, a first current collector 150, and a first sealing element 160.

[0062] Specifically, the housing 110 has a receiving cavity 111; the electrode assembly 120 is disposed in the receiving cavity 111; the first end cap 131 is connected to one end of the housing 110 in the axial direction Z to seal the receiving cavity 111 of the housing 110; the electrode post 140 passes through the first end cap 131 in the axial direction Z, and the electrode post 140 and the first end cap 131 are insulated from each other to avoid contact between the two and causing a short circuit in the single cell 100; the first current collector 150 includes: a first current collector portion 151 and a first protrusion portion 152, the first current collector portion 151 is disposed between the first end cap 131 and the electrode assembly 120, and the first current collector portion 151 is electrically connected to the electrode assembly 120, and the first protrusion portion 152 protrudes from the first current collector portion 151. On one side away from the electrode assembly 120, a first protrusion 152 is inserted through the electrode post 140 along the axial direction Z. The first protrusion 152 is electrically connected to the electrode post 140 to form a conductive circuit of electrode assembly 120-first current collector 151-first protrusion 152-electrode post 140. The first protrusion 152 has a first through hole 1521 extending along the axial direction Z, which communicates with the receiving cavity 111. A first sealing member 160 is disposed in the first through hole 1521 and blocks the first through hole 1521. Both the first sealing member 160 and the first protrusion 152 are welded to the electrode post 140 to achieve positioning and fixation among the electrode post 140, the first current collector 150, and the first sealing member 160. Optionally, a sealing member 160 and the first protrusion 152 are welded together to the electrode post 140 from the first sealing member 160.

[0063] The single cell 100 can be a rechargeable battery, which refers to a single cell that can be recharged after discharge to activate the active materials and continue to be used. For example, the single cell 100 can be a lithium-ion battery, sodium-ion battery, sodium-lithium-ion battery, lithium metal battery, sodium metal battery, lithium-sulfur battery, magnesium-ion battery, nickel-metal hydride battery, or nickel-cadmium battery, but is not limited to these.

[0064] The single cell 100 can be a prismatic cell, a pouch cell, or a cell of other shapes. For example, in this application, the single cell 100 is a cylindrical lithium-ion cell.

[0065] The housing 110 may be made of a strong material such as metal, but is not limited to this. For example, the housing 110 may be made of aluminum profile, but is not limited to this.

[0066] The first end cap 131 can be integrally formed with the housing 110, meaning the first end cap 131 and the housing 110 are a single integrated structure. The first end cap 131 can also be fixedly connected to the housing 110, for example, by welding or other processes, to one side of the housing 110 along the Z-axis. This application does not impose specific limitations and can be configured according to actual circumstances. For example, in this application, the first end cap 131 is integrally formed with the housing 110.

[0067] The first current collector 150 can be a positive current collector or a negative current collector. This application does not make specific limitations and can be set according to the actual situation.

[0068] The material of the first current collector 150 can be various. For example, the material of the first current collector 150 can be copper, iron, aluminum, steel or aluminum alloy, but it is not limited to these.

[0069] The first current collector 151 and the first protrusion 152 can be integrally formed, that is, the first current collector 151 and the first protrusion 152 are a single-piece structure; alternatively, the first current collector 151 and the first protrusion 152 can be separately arranged, and the two are fixedly connected. For example, the first protrusion 152 is fixedly connected to the first current collector 151 by welding or other processes. This application does not impose specific limitations, and the specific configuration can be determined according to actual circumstances. For example, in this application, the first current collector 151 and the first protrusion 152 are integrally die-cast.

[0070] The single-cell battery 100 also includes an electrolyte and other functional components. The electrolyte can be a conventional electrolyte or a special electrolyte with additives. The electrolyte is used to wet the electrode assembly 120. The electrode assembly 120 is the component in the single-cell battery 100 where electrochemical reactions occur, and there can be one or more electrode assemblies. The electrode assembly 120 is mainly formed by winding a positive electrode sheet, a negative electrode sheet, and a separator. The portions of the positive and negative electrode sheets with active materials constitute the main body of the electrode assembly 120, while the portions without active materials constitute the tabs. During the charging and discharging process of the single-cell battery 100, the positive and negative active materials react with the electrolyte. The tabs are electrically connected to the terminal post 140 through the first current collector 150 to form a current loop, enabling the single-cell battery 100 to function normally.

[0071] Understandably, in this application, the first seal 160 and the first protrusion 152 are welded together to the terminal post 140 from the first seal 160, thereby fixing the terminal post 140, the first current collector 150, and the first seal 160 on the outside of the casing 110 of the single battery 100. This prevents dust generated during welding from entering the casing 110, avoiding short circuits in the single battery 100 and improving the safety performance of the single battery 100. Furthermore, this application achieves the welding and fixing of the terminal post 140, the first current collector 150, and the first seal 160 through a single welding process, reducing the number of single battery 140 components required for welding. The welding process during assembly optimizes the overall assembly production process of the single cell 100, reduces the overall defect rate of the single cell 100, and improves the production efficiency of the single cell 100. At the same time, by embedding the first sealing element 160 into the first through hole 1521 of the first current collector element 150, a bushing fit structure is formed between the first current collector element 150 and the first sealing element 160. The bushing fit structure eliminates the assembly tolerance during the assembly process of the single cell 100, ensures that the components in the single cell 100 are tightly assembled and connected, thereby ensuring the overall structural stability of the single cell 100 and further improving the safety and reliability of the single cell 100.

[0072] In a specific embodiment of this application, refer to Figures 3 to 5 The electrode post 140 has a second through hole 141 extending along the Z-axis. The first protrusion 152 is embedded in the second through hole 141, so that the electrode post 140 and the first current collector 150 form a bushing fit structure. This bushing fit structure further eliminates the assembly tolerance during the assembly process of the single cell 100, further ensures the tight assembly and connection of each component in the single cell 100, and thus ensures the overall structural stability of the single cell 100, and further improves the safety and reliability of the single cell 100.

[0073] Specifically, a welding groove 161 is provided on the side of the first sealing member 160 away from the electrode assembly 120. The welding groove 161 has a first groove wall 162 extending along the axial direction Z. The first sealing member 160 and the first protrusion 152 are welded together to the terminal post 140 from the first groove wall 162. That is, the terminal post 140, the first current collector 150 and the first sealing member 160 are welded and fixed on the outside of the housing 110 of the single cell 100, so that the dust generated during welding cannot enter the housing 110, thus avoiding the short circuit of the single cell 100 caused by the dust generated during welding, and improving the safety performance of the single cell 100. At the same time, the terminal post 140, the first current collector 150 and the first sealing member 160 are welded and fixed through a single welding process, reducing the welding process during the assembly of the single cell 100, optimizing the overall assembly production process of the single cell 100, reducing the overall defect rate of the single cell 100 and improving the production efficiency of the single cell 100.

[0074] In some embodiments, the first seal 160 and the first protrusion 152 are welded together to the pole post 140 from the first groove wall 162 to form a weld mark 164 on the first groove wall 162. The shape of the weld mark 164 can be any one of rectangle, circle, triangle, fan, arc or serpentine, but is not limited thereto.

[0075] The outer surface of solder mark 164 may or may not be chamfered. This application does not impose specific limitations and the choice can be made according to the actual situation.

[0076] In some embodiments, the melting point of the material of the pole post 140 is T1℃, the melting point of the material of the first current collector 150 is T2℃, and the melting point of the material of the first seal 160 is T3℃, satisfying T1=T2=T3, so as to weld and fix the pole post 140, the first current collector 150 and the first seal 160 by means of superimposed integral welding, and to ensure the welding effect after welding is completed.

[0077] In some embodiments, refer to Figures 3 to 5 The first current collector 150 further includes a support portion 153, which is disposed on the side of the first through hole 1521 near the electrode assembly 120 and connected to the hole wall of the first through hole 1521. That is, the support portion 153 is connected to the first protrusion 152. The side of the support portion 153 away from the electrode assembly 120 abuts against the first seal 160, so as to support the first seal 160 by the support portion 153, thereby ensuring that the first seal 160 is tightly fitted to the hole wall of the first through hole 1521, thereby ensuring the welding effect between the electrode post 140, the first current collector 150 and the first seal 160, and improving the overall welding efficiency of the single cell 100.

[0078] The support portion 153 and the first protrusion 152 can be integrally formed, meaning they are a single, integrated structure. Alternatively, the support portion 153 and the first protrusion 152 can be separately configured and fixedly connected. For example, the support portion 153 is fixedly connected to the first protrusion 152 via welding or other processes. This application does not impose specific limitations and can be configured according to actual circumstances. For example, in this application, the support portion 153 and the first protrusion 152 are integrally die-cast.

[0079] In some embodiments, the single cell 100 further has a reference plane P perpendicular to the axial direction Z, and the orthogonal projection area of ​​the support portion 153 on the reference plane P along the axial direction Z is S1 mm. 2 The condition is satisfied that S1 ≥ 45. That is, the orthographic projection area of ​​the support part 153 on the reference plane P is S1 mm. 2 Not less than 45mm 2 For example, S1 mm 2 It can be 45mm 2 50mm 2 55mm 2 60mm 2 65mm 2 70mm 2 75mm 2 80mm 2 85mm 2 90mm 2 95mm 2 Or 100mm 2 The range consisting of one or any two of them. S1mm 2 The specific values ​​mentioned above are given only as examples, as long as they are not less than 45mm. 2 Any value of is within the scope of protection of this application.

[0080] Along the axial direction Z, the orthographic projection area of ​​the support portion 153 on the reference plane P is S1 mm. 2 The actual single cell 100 can be disassembled, and the first current collector 150 can be photographed and projected multiple times along the Z-axis using a projection measurement device (such as a digital microscope or image measuring instrument) to measure the image area of ​​the support portion 153 of the first current collector 150, thereby obtaining the orthogonal projection area S1 mm of the support portion 153 on the reference plane P. 2 However, it is not limited to this.

[0081] Understandably, when the orthographic projection area of ​​the support 153 on the reference plane P is S1 mm... 2 Less than 45mm 2If the support strength of the support part 153 is insufficient, it is difficult to effectively support the first seal 160, which can easily lead to the misalignment of the axis between the first current collector 150 and the first seal 160, resulting in welding failure and affecting the overall welding efficiency and production efficiency of the single cell 100.

[0082] This application defines the orthographic projection area S1 mm of the support portion 153 on the reference plane P. 2 Not less than 45mm 2 This ensures that the support portion 153 has sufficient area to contact the first seal 160, and that the support portion 153 has sufficient support strength to effectively support the first seal, thereby ensuring the welding effect between the pole post 140, the first current collector 150 and the first seal 160, and improving the overall welding efficiency of the single cell 100.

[0083] In some embodiments, refer to Figure 5 The support portion 153 has an injection hole 1531 that extends through the Z axis. The injection hole 1531 is connected to the first through hole 1521 and the receiving cavity 111, so that the first through hole 1521 and the receiving cavity 111 are connected. Electrolyte can be transported from the injection hole 1531 to the receiving cavity 111 of the housing 110 to wet the electrode assembly 120.

[0084] In some embodiments, the inner contour dimension of the injection hole 1531 is D5 mm, satisfying: 3 ≤ D5 ≤ 8. That is, the inner contour dimension D5 mm of the injection hole 1531 can be controlled within the range of 3 mm to 8 mm. For example, D5 mm can be one or a combination of any two of 3 mm, 4 mm, 5 mm, 6 mm, 7 mm, or 8 mm. The specific values ​​of D5 mm given above are merely illustrative, and any value within the range of 3 mm to 8 mm is within the protection scope of this application.

[0085] For example, in this application, the injection hole 1531 is circular, and the inner contour dimension of the injection hole 1531 is the diameter of the injection hole 1531.

[0086] The inner contour dimension D5 mm of the injection hole 1531 can be obtained by disassembling the actual single cell 100 and measuring the diameter of the injection hole 1531 on the first current collector element 150 multiple times using a measuring tool and calculating the average value. The measuring tool can be any one of a ruler, vernier caliper, or other dimensional measuring instruments, but is not limited to this.

[0087] When the inner contour dimension D5 mm of the injection hole 1531 is less than 3 mm, the electrolyte is easily splashed onto the side wall of the first current collector 150 when the single cell 100 is injected through the injection hole 1531, thus affecting subsequent welding operations. When the inner contour dimension D5 mm of the injection hole 1531 is greater than 8 mm, the injection hole 1531 becomes too large, and the electrolyte is easily volatilized when the single cell 100 is injected, affecting the injection effect.

[0088] This application limits the inner contour dimension D5 mm of the injection hole 1531 to the range of 3 mm to 8 mm to reasonably design the structural dimensions of the injection hole 1531. This ensures the injection effect of the single cell 100 while avoiding the impact on other components during the injection of the single cell 100, thus ensuring the production and assembly efficiency of the single cell 100.

[0089] In some embodiments, refer to Figures 3 to 6 The first current collector 150 further includes a second protrusion 154, which protrudes from the side of the first current collector 151 away from the electrode assembly 120 and is connected to the outer wall of the first protrusion 152. The second protrusion 154 and the terminal post 140 are spaced apart in the axial direction Z, that is, there is a gap space between the second protrusion 154 and the terminal post 140 in the axial direction Z, so that the assembly tolerance of the single cell 100 in the axial direction Z only affects the gap space between the second protrusion 154 and the terminal post 140. The gap space between the second protrusion 154 and the terminal post 140 is used to further eliminate the assembly tolerance of the single cell 100 assembly process, and ensure that the welding of the terminal post 140, the first current collector 150 and the first seal 160 is not affected. At the same time, it ensures that the components in the single cell 100 are tightly assembled and connected, thereby ensuring the overall structural stability of the single cell 100 and further improving the safety and reliability of the single cell 100.

[0090] For example, in this application, the distance between the second protrusion 154 and the electrode post 140 in the axial direction Z is greater than the assembly tolerance of the single cell 100 in the axial direction Z.

[0091] In some embodiments, refer to Figures 3 to 6 The first current collection section 151 includes a plurality of reinforcing sections 155 and a plurality of welding sections 156, with each reinforcing section 155 and each welding section 156 alternately arranged around the outer edge of the second protrusion 154 along the circumferential direction R.

[0092] The first current collector 150 is welded and fixed to the electrode assembly 120 at each welding part 156.

[0093] Understandably, this application improves the overall strength of the first current collector 151 by providing multiple reinforcing parts 155, preventing the first current collector 151 from deforming under stress, thereby ensuring efficient connection between the first current collector 151 and the electrode assembly 120 and ensuring the overall structural stability of the single cell 100. At the same time, this application provides multiple welding parts 156 to weld and fix the electrode assembly 120 through each welding part 156, thereby realizing the electrical connection between the two and forming a current conduction circuit between them, ensuring the overcurrent performance of the single cell 100.

[0094] In some embodiments, refer to Figure 6 Each reinforcing part 155 extends along the radial direction X, and in the radial direction X, along the direction from the first protrusion 152 toward the second protrusion 154, the thickness of each reinforcing part 155 in the axial direction Z gradually decreases.

[0095] Understandably, since the first protrusion 152 of the first current collector 150 needs to be welded to the pole post 140 and the first seal, and the support 153 abuts against the first seal 160, the side of each reinforcing part 155 closer to the first protrusion 152 in the radial X direction is subjected to more force, while the side farther from the first protrusion 152 is subjected to less force. Therefore, in this application, along the direction from the first protrusion 152 to the second protrusion 154, the thickness of each reinforcing part 155 in the axial Z direction gradually decreases. This is to rationally design the structure of each reinforcing part 155, ensuring that the structural strength of each reinforcing part 155 is higher in the radial X direction closer to the first protrusion 152, and lower in the radial X direction farther from the first protrusion 152. This satisfies the structural strength design of each reinforcing part 155 at different positions, preventing deformation of each reinforcing part 155 under stress at different positions while reducing costs.

[0096] In some embodiments, the sum of the orthographic projection areas of each reinforcing part 155 on the reference plane P is S² mm. 2 The orthographic projection area of ​​the first collector 151 on the reference plane P is S3 mm. 2 This satisfies: 1 / 3 ≤ S2 / S3 ≤ 1 / 2. That is, the sum of the orthographic projection areas of each reinforcing part 155 on the reference plane P is S2 mm. 2 The orthographic projection area of ​​the first collector 151 on the reference plane P is S3mm. 2The ratio can be controlled within the range of 1 / 3 to 1 / 2. For example, S2 / S3 can be a range consisting of one or more of 1 / 3, 0.34, 0.35, 0.36, 0.37, 0.38, 0.39, 0.4, 0.42, 0.44, 0.46, 0.48, or 1 / 2, or any combination thereof. The specific values ​​of S2 / S3 given above are merely illustrative; any value within the range of 1 / 3 to 1 / 2 is within the scope of protection of this application.

[0097] The sum of the orthographic projection areas of each reinforcing part 155 on the reference plane P is S2 mm. 2 The actual single cell 100 can be disassembled, and the first current collector 150 can be photographed and projected multiple times along the Z-axis using a projection measurement device (such as a digital microscope or image measuring instrument) to measure the image area of ​​the reinforcing part 155 on the first current collector 150. The image areas of each reinforcing part 155 are then summed to obtain the sum of the orthographic projection areas S2 mm of each reinforcing part 155 on the reference plane P. 2 However, it is not limited to this.

[0098] The orthogonal projection area S3 mm2 of the first current collector 151 on the reference plane P can be obtained by disassembling the actual single cell 100 and taking multiple images of the first current collector 150 along the Z-axis using a projection measurement device (such as a digital microscope or image measuring instrument) to measure the image area of ​​the first current collector 151 on the first current collector 150, thereby obtaining the orthogonal projection area S3 mm2 of the first current collector 151 on the reference plane P. 2 However, it is not limited to this.

[0099] Understandably, when S2 / S3 is less than 1 / 3, the overall area of ​​each reinforcing part 155 is relatively small, the structural strength of the reinforcing part 155 is insufficient, and the first current collector 151 is easily deformed by force; when S2 / S3 is greater than 1 / 2, the overall area of ​​multiple welding parts 156 is relatively small, the current flow area between the first current collector element 150 and the electrode assembly 120 is relatively small, affecting the current flow performance of the single cell 100.

[0100] This application limits the sum of the orthographic projection areas of each reinforcing part 155 on the reference plane P to S2 mm. 2 The orthographic projection area of ​​the first collector 151 on the reference plane P is S3 mm. 2The ratio is in the range of 1 / 3 to 1 / 2, so as to reasonably design the structural dimensions of the first current collector 150, to ensure the structural strength of each reinforcing part 155, prevent the first current collector 151 from being deformed by force, thereby ensuring efficient connection between the first current collector 151 and the electrode assembly 120, and ensuring the overall structural stability of the single cell 100; at the same time, ensuring the current flow area between each welding part 156 and the electrode assembly 120, and ensuring the current flow performance of the single cell 100.

[0101] In some embodiments, refer to Figure 5 The first sealing element 160 and the hole wall of the first through hole 1521 adopt a transition fit, that is, the outer contour dimension of the first sealing element 160 can be larger than the inner contour dimension of the first through hole 1521, and the outer contour dimension of the first sealing element 160 can also be smaller than or equal to the inner contour dimension of the first through hole 1521, so that the outer wall of the first sealing element 160 fits the hole wall of the first through hole 1521, ensuring that the welding of the pole post 140, the first current collector element 150 and the first sealing element 160 is not affected.

[0102] Specifically, the outer contour dimension of the first sealing element 160 is D1 mm, and the inner contour dimension of the first through hole 1521 is D2 mm, satisfying: |D1-D2|≤0.05; that is, the absolute value of the difference between the outer contour dimension D1 mm of the first sealing element 160 and the inner contour dimension D2 mm of the first through hole 1521 can be controlled within a range not exceeding 0.05 mm. For example, |D1-D2| can be a range consisting of one or any two of 0.02 mm, 0.025 mm, 0.03 mm, 0.035 mm, 0.04 mm, 0.045 mm, or 0.05 mm. The specific values ​​of |D1-D2| are given as examples only; any value within the range not exceeding 0.05 mm is within the protection scope of this application.

[0103] For example, in this application, the first seal 160 is cylindrical, and the outer contour dimension of the first seal 160 is the outer diameter of the first seal 160; the first through hole 1521 is circular, and the inner contour dimension of the first through hole 1521 is the hole diameter of the first through hole 1521.

[0104] The outer contour dimension D1 mm of the first seal 160 can be obtained by disassembling the actual single cell 100, measuring the outer diameter of the first seal 160 multiple times using measuring tools, and calculating the average value. The measuring tool can be any one of a ruler, vernier caliper, or other dimensional measuring instruments, but is not limited to these.

[0105] The inner contour dimension D2 mm of the first through hole 1521 can be obtained by disassembling the actual single cell 100 and measuring the diameter of the first through hole 1521 on the first current collector 150 multiple times using a measuring tool and calculating the average value. The measuring tool can be any one of a ruler, vernier caliper, or other dimensional measuring instruments, but is not limited to this.

[0106] When |D1-D2| is less than 0.02mm, the first seal 160 may not be able to be installed into the first through hole 1521 during the assembly of the single cell 100, affecting the normal assembly of the single cell 100. When |D1-D2| is greater than 0.05mm, the outer wall of the first seal 160 may not fit well with the hole wall of the first through hole 1521, resulting in poor welding of the electrode post 140, the first current collector 150 and the first seal 160, affecting the welding effect.

[0107] This application limits the absolute value of the difference between the outer contour dimension D1 mm of the first seal 160 and the inner contour dimension D2 mm of the first through hole 1521 to no more than 0.05 mm, so as to reasonably design the structural dimensions of the first seal 160 and the first through hole 1521, thereby ensuring normal assembly between the first seal 160 and the first through hole 1521 and ensuring the assembly efficiency of the single cell 100; at the same time, it ensures the fit between the outer wall of the first seal 160 and the hole wall of the first through hole 1521, ensuring that the welding of the electrode post 140, the first current collector 150 and the first seal 160 is not affected, and ensuring the welding effect between the electrode post 140, the first current collector 150 and the first seal 160.

[0108] In some embodiments, refer to Figure 5 The first protrusion 152 and the wall of the second through hole 141 adopt a transition fit, that is, the outer contour dimension of the first protrusion 152 can be larger than the inner contour dimension of the second through hole 141, and the outer contour dimension of the first protrusion 152 can also be smaller than or equal to the inner contour dimension of the second through hole 141, so that the outer wall of the first protrusion 152 fits the wall of the second through hole 141, ensuring that the welding of the pole post 140, the first current collector 150 and the first seal 160 is not affected.

[0109] Specifically, the outer contour dimension of the first protrusion 152 is D3 mm, and the inner contour dimension of the second through hole 141 is D4 mm, satisfying |D3-D4|≤0.05. That is, the absolute value of the difference between the outer contour dimension D3 mm of the first protrusion 152 and the inner contour dimension D4 mm of the second through hole 141 can be controlled to be within a range not exceeding 0.05 mm. For example, |D3-D4| can be one of 0.02 mm, 0.025 mm, 0.03 mm, 0.035 mm, 0.04 mm, 0.045 mm, or 0.05 mm, or any combination thereof. The specific values ​​of |D3-D4| are given as examples only; any value within the range not exceeding 0.05 mm is within the protection scope of this application.

[0110] For example, in this application, the first protrusion 152 is cylindrical, and the outer contour dimension of the first protrusion 152 is the outer diameter of the first protrusion 152; the second through hole 141 is circular, and the inner contour dimension of the second through hole 141 is the hole diameter of the second through hole 141.

[0111] The method for measuring the outer contour dimension D3 mm of the first protrusion 152 is the same as the method for measuring the outer contour dimension D1 mm of the first seal 160, and the method for measuring the inner contour dimension D4 mm of the second through hole 141 is the same as the method for measuring the inner contour dimension D2 mm of the first through hole 1521. These methods will not be elaborated further here, but can be referred to the above description.

[0112] When |D3-D4| is less than 0.02mm, the first protrusion 152 may not be able to be installed into the second through hole 141 during the assembly of the single cell 100, affecting the normal assembly of the single cell 100. When |D3-D4| is greater than 0.05mm, the outer wall of the first protrusion 152 and the hole wall of the second through hole 141 may not fit well, resulting in poor welding of the electrode post 140, the first current collector 150 and the first seal 160, affecting the welding effect.

[0113] This application limits the absolute value of the difference between the outer contour dimension D3 mm of the first protrusion 152 and the inner contour dimension D4 mm of the second through hole 141 to no more than 0.05 mm, so as to reasonably design the structural dimensions of the first protrusion 152 and the second through hole 141, thereby ensuring normal assembly between the first protrusion 152 and the second through hole 141 and ensuring the assembly efficiency of the single cell 100; at the same time, it ensures the fit between the outer wall of the first protrusion 152 and the hole wall of the second through hole 141, further ensuring that the welding of the electrode post 140, the first current collector 150 and the first seal 160 is not affected, and further ensuring the welding effect between the electrode post 140, the first current collector 150 and the first seal 160.

[0114] In some embodiments, refer to Figures 3 to 5 The single cell 100 also includes: a riveting member 191, a third sealing member 192, and an insulating member 193. The riveting member 191 and the third sealing member 192 are both disposed between the terminal post 140 and the first end cover 131 to insulate the terminal post 140 from the first end cover 131. Part of the insulating member 193 is disposed between the terminal post 140 and the first end cover 131 to insulate the terminal post 140 from the first end cover 131, and another part of the insulating member 193 is disposed between the first current collector 150 and the first end cover 131 to insulate the first current collector 150 from the first end cover 131.

[0115] The riveting component 191, the third sealing component 192, and the insulating component 193 are all made of insulating material. For example, the riveting component 191, the third sealing component 192, and the insulating component 193 are all made of plastic, but are not limited thereto.

[0116] In the second specific embodiment of this application, refer to Figures 7 to 8 The electrode post 140 has a second through hole 141 extending along the Z-axis, and the first protrusion 152 is embedded in the second through hole 141; the first sealing member 160 has an end wall 163 on the side away from the electrode assembly 120, and the first sealing member 160 and the first protrusion 152 are welded together to the electrode post 140 from the end wall 163.

[0117] Understandably, in this application, the first sealing element 160 and the first protrusion 152 are welded together to the terminal post 140 from the end wall 163, thereby fixing the terminal post 140, the first current collector 150, and the first sealing element 160 on the outside of the casing 110 of the single battery 100. This prevents dust generated during welding from entering the casing 110, avoiding short circuits in the single battery 100 and improving the safety performance of the single battery 100. Furthermore, this application achieves the welding and fixing of the terminal post 140, the first current collector 150, and the first sealing element 160 through a single welding process, reducing... The welding process during the assembly of the single battery 100 is simplified, the overall assembly production process of the single battery 100 is optimized, the overall defect rate of the single battery 100 is reduced, and the production efficiency of the single battery 100 is improved. At the same time, by embedding the first protrusion 152 into the second through hole 141, a bushing fit structure is formed between the first current collector 150 and the terminal post 140. The bushing fit structure is used to eliminate the assembly tolerance during the assembly process of the single battery 100, ensuring that the components in the single battery 100 are tightly assembled and connected, thereby ensuring the overall structural stability of the single battery 100 and further improving the safety and reliability of the single battery 100.

[0118] Meanwhile, other technical features in the second specific embodiment of this application are the same as those in the first specific embodiment described above. Since the features have been described in detail in the first specific embodiment described above, the second specific embodiment of this application will not be described accordingly. For details, please refer to the description in the first specific embodiment.

[0119] In the specific embodiment three of this application, refer to Figures 9 to 12 The electrode post 140 has a second through hole 141 extending along the Z-axis, and a first fixing groove 142 is formed on the side of the electrode post 140 near the electrode assembly 120; a first protrusion 152 is embedded in the first fixing groove 142, and a first sealing member 160 is embedded in the second through hole 141 on the side away from the electrode assembly 120, and the side of the first sealing member 160 near the electrode assembly 120 is disposed in the first through hole 1521; a welding groove 161 is formed on the side of the first sealing member 160 away from the electrode assembly 120, and the welding groove 161 has a first groove wall 162 extending along the Z-axis, and the first sealing member 160 and the first protrusion 152 are welded together to the electrode post 140 from the first groove wall 162.

[0120] Understandably, in this application, the first sealing element 160 and the first protrusion 152 are welded together to the terminal post 140 from the first groove wall 162, thereby fixing the terminal post 140, the first current collector 150, and the first sealing element 160 on the outside of the casing 110 of the single battery 100. This prevents dust generated during welding from entering the casing 110, thus avoiding short circuits in the single battery 100 and improving the safety performance of the single battery 100. Furthermore, this application achieves the welding and fixing of the terminal post 140, the first current collector 150, and the first sealing element 160 through a single welding process, reducing the welding steps during the assembly of the single battery 100, optimizing the overall assembly and production process of the single battery 100, and reducing the cost of single battery assembly. The overall defect rate of the battery 100 is reduced, improving the production efficiency of the single battery 100. Simultaneously, this application embeds the first protrusion 152 into the first fixing groove 142, embeds the side of the first seal 160 away from the electrode assembly 120 into the second through hole 141, and sets the side of the first seal 160 near the electrode assembly 120 within the first through hole 1521. This creates a bushing fit structure between the first current collector 150 and the first seal 160, and between the first current collector 150 and the terminal post 140. This bushing fit structure eliminates assembly tolerances during the assembly process of the single battery 100, ensuring tight assembly and connection of all components in the single battery 100, thereby guaranteeing the overall structural stability of the single battery 100 and further improving its safety and reliability.

[0121] In some embodiments, refer to Figures 9 to 11The first fixing groove 142 extends along the axial direction Z, and the first fixing groove 142 has a second groove wall 1421 on the side of the first fixing groove 142 away from the electrode assembly 120 in the axial direction Z. The first protrusion 152 and the second groove wall 1421 are spaced apart in the axial direction Z. The electrode post 140 and the first current collector 151 are also spaced apart in the axial direction Z. That is, there are gap spaces in the axial direction Z between the first protrusion 152 and the second groove wall 1421, and between the electrode post 140 and the first current collector 151, so that the assembly tolerance of the single cell 100 in the axial direction Z only affects the first protrusion 152 and the second groove wall 1421. The gaps between the first protrusion 152 and the second groove wall 1421, and between the terminal post 140 and the first current collector 151, are used to eliminate assembly tolerances in the assembly process of the single cell 100, ensuring that the welding of the terminal post 140, the first current collector 150 and the first seal 160 is not affected; at the same time, it ensures that the components in the single cell 100 are tightly assembled and connected, thereby ensuring the overall structural stability of the single cell 100 and further improving the safety and reliability of the single cell 100.

[0122] In some embodiments, refer to Figure 11 The first sealing element 160 and the hole wall of the second through hole 141 adopt a transition fit, that is, the outer contour dimension of the first sealing element 160 can be larger than the inner contour dimension of the second through hole 141, and the outer contour dimension of the first sealing element 160 can also be smaller than or equal to the inner contour dimension of the second through hole 141, so that the outer wall of the first sealing element 160 fits the hole wall of the second through hole 141, ensuring that the welding of the pole post 140, the first current collector element 150 and the first sealing element 160 is not affected.

[0123] Specifically, the outer contour dimension of the first sealing element 160 is D1 mm, and the inner contour dimension of the second through hole 141 is D4 mm, satisfying: |D1-D4|≤0.05. That is, the absolute value of the difference between the outer contour dimension D1 mm of the first sealing element 160 and the inner contour dimension D4 mm of the second through hole 141 can be controlled within a range not exceeding 0.05 mm. For example, |D1-D4| can be a range of one or any two of 0.02 mm, 0.025 mm, 0.03 mm, 0.035 mm, 0.04 mm, 0.045 mm, or 0.05 mm. The specific values ​​of |D1-D4| are given as examples only, and any value within the range not exceeding 0.05 mm is within the protection scope of this application.

[0124] When |D1-D4| is less than 0.02mm, the first seal 160 may not be able to be installed into the second through hole 141 during the assembly of the single cell 100, affecting the normal assembly of the single cell 100. When |D1-D4| is greater than 0.05mm, the outer wall of the first seal 160 and the hole wall of the second through hole 141 may not fit well, resulting in poor welding of the electrode post 140, the first current collector 150 and the first seal 160, affecting the welding effect.

[0125] This application limits the absolute value of the difference between the outer contour dimension D1 mm of the first sealing element 160 and the inner contour dimension D4 mm of the second through hole 141 to no more than 0.05 mm, so as to reasonably design the structural dimensions of the first sealing element 160 and the second through hole 141, thereby ensuring normal assembly between the first sealing element 160 and the second through hole 141 and ensuring the assembly efficiency of the single cell 100; at the same time, it ensures the fit between the outer wall of the first sealing element 160 and the hole wall of the second through hole 141, ensuring that the welding of the electrode post 140, the first current collector 150 and the first sealing element 160 is not affected, and ensuring the welding effect between the electrode post 140, the first current collector 150 and the first sealing element 160.

[0126] Meanwhile, other technical features in the third embodiment of this application are the same as those in the first embodiment described above. Since the features have been described in detail in the first embodiment, the third embodiment of this application will not be described in the same way. For details, please refer to the description in the first embodiment.

[0127] In the fourth specific embodiment of this application, it is further formed based on the first, second or third specific embodiments described above.

[0128] Specifically, refer to Figures 13 to 17 The single cell 100 also includes: a second end cap 132, a second current collector 170, and a second seal 180.

[0129] Specifically, the second end cap 132 is disposed on the side of the housing 110 away from the first end cap 131 in the axial direction Z, and the second end cap 132 has a third through hole 1323 extending in the axial direction Z; the second current collector 170 is disposed in the receiving cavity 111, and the second current collector 170 is disposed between the second end cap 132 and the electrode assembly 120, and the second current collector 170 is electrically connected to the electrode assembly 120 and the second end cap 132 respectively; the second sealing member 180 is embedded in the third through hole 1323 and blocks the third through hole 1323.

[0130] The second seal 180 and the wall of the third through hole 1323 are fitted with a transition fit.

[0131] This application embeds the second seal 180 into the third through hole 1323, so that a bushing fit structure is formed between the second end cap 132 and the second seal 180. This bushing fit structure further eliminates the assembly tolerance during the assembly process of the single cell 100, ensuring that the components in the single cell 100 are tightly assembled and connected, thereby ensuring the overall structural stability of the single cell 100 and further improving the safety and reliability of the single cell 100.

[0132] In some embodiments, the second seal 180 and the second end cap 132 are welded together from the second seal 180 to the second current collector 170, so as to weld and fix the second seal 180, the second end cap 132 and the second current collector 170 on the outside of the housing 110 of the single cell 100, so that the dust generated during welding cannot enter the housing 110, further avoiding the short circuit of the single cell 100 caused by the dust generated during welding entering the housing 110, and improving the safety performance of the single cell 100. Moreover, in this application, the second seal 180, the second end cap 132 and the second current collector 170 are welded and fixed through a single welding process, which reduces the welding process during the assembly of the single cell 100, optimizes the overall assembly production process of the single cell 100, reduces the overall defect rate of the single cell 100 and improves the production efficiency of the single cell 100.

[0133] In some embodiments, refer to Figures 15 to 17 The second end cap 132 includes a cap body portion 1321 and a third protrusion portion 1322. The cap body portion 1321 is disposed on the side of the housing 110 away from the first end cap 131 in the axial direction Z. The third protrusion portion 1322 protrudes from the cap body portion 1321 on the side close to the electrode assembly 120, and a third through hole 1323 is provided on the third protrusion portion 1322 in the axial direction Z.

[0134] The second current collector 170 includes a second current collector 171 and a fourth protrusion 172. The second current collector 171 is disposed between the second end cap 132 and the electrode assembly 120, and the second current collector 171 is electrically connected to the electrode assembly 120. The fourth protrusion 172 protrudes from the side of the second current collector 171 away from the electrode assembly 120, and a second fixing groove 1721 is formed on the side of the fourth protrusion 172 away from the second current collector 171. A third protrusion 1322 is embedded in the second fixing groove 1721, and the third protrusion 1322 is electrically connected to the fourth protrusion 172.

[0135] The cover portion 1321 and the third protrusion 1322 can be integrally formed, meaning they are a single, integrated structure. Alternatively, the cover portion 1321 and the third protrusion 1322 can be separately configured and fixedly connected. For example, the third protrusion 1322 is fixedly connected to the cover portion 1321 by welding or other processes. This application does not impose specific limitations and can be configured according to actual circumstances. For example, in this application, the cover portion 1321 and the third protrusion 1322 are integrally die-cast.

[0136] The second current collector 171 and the fourth protrusion 172 can be integrally formed, that is, the second current collector 171 and the fourth protrusion 172 are a one-piece structure; alternatively, the second current collector 171 and the fourth protrusion 172 can be separately arranged, and the two are fixedly connected. For example, the fourth protrusion 172 is fixedly connected to the second current collector 171 by welding or other processes. This application does not impose specific limitations, and the specific configuration can be determined according to the actual situation. For example, in this application, the second current collector 171 and the fourth protrusion 172 are integrally die-cast.

[0137] The third protrusion 1322 and the groove wall of the second fixing groove 1721 are fitted with a transition fit.

[0138] This application embeds the third protrusion 1322 into the second fixing groove 1721, so that a bushing fit structure is formed between the second end cover 132 and the second current collector 170. This bushing fit structure further eliminates the assembly tolerance during the assembly process of the single cell 100, ensuring that the components in the single cell 100 are tightly assembled and connected, thereby ensuring the overall structural stability of the single cell 100 and further improving the safety and reliability of the single cell 100.

[0139] For example, the second seal 180 and the third protrusion 1322 are welded together from the second seal 180 to the fourth protrusion 172.

[0140] In some embodiments, refer to Figures 15 to 17In the Z-axis direction, the third protrusion 1322 is spaced apart from the second current collector 171, and the fourth protrusion 172 is spaced apart from the cover portion 1321. That is, there is a gap space in the Z-axis direction between the third protrusion 1322 and the second current collector 171, and a gap space in the Z-axis direction between the fourth protrusion 172 and the cover portion 1321. This ensures that the assembly tolerance of the single cell 100 in the Z-axis direction only affects the gap space between the third protrusion 1322 and the second current collector 171, and between the fourth protrusion 172 and the cover portion 1321. The gaps between the third protrusion 1322 and the second current collector 171, and between the fourth protrusion 172 and the cover 1321, are used to eliminate assembly tolerances in the assembly process of the single cell 100, ensuring that the welding of the second seal 180, the second end cover 132 and the second current collector 170 is not affected; at the same time, it ensures that the components in the single cell 100 are tightly assembled and connected, thereby ensuring the overall structural stability of the single cell 100 and further improving the safety and reliability of the single cell 100.

[0141] Meanwhile, other technical features in the fourth embodiment of this application are the same as those in the first, second, or third embodiment described above. Since the features have been described in detail in the first, second, and third embodiments described above, the fourth embodiment of this application will not be described in the same way. For details, please refer to the descriptions in the first, second, and third embodiments.

[0142] In one embodiment, the single cell 100 of this application can be prepared using any known method. For example, in this application, a positive electrode and a negative electrode are prepared using conventional processes. After drying, the positive and negative electrode sheets, together with a separator, are wound together to form an electrode assembly 120. The riveting member 191, the third sealing member 192, and the insulating member 193 are riveted together with the first end cap 131 via the electrode post 140. The first end cap 131 is then connected to the housing 110. The first current collector 150 and the second current collector 170 are welded to the tabs of the electrode assembly 120. After welding, the electrode assembly 120 is coated with adhesive, and the electrode assembly 120 is assembled into the receiving cavity 111 of the housing 110 from the second end cap 132 side. After the second end cap 132 is closed and welded to the housing 110, the second sealing member 180 is assembled to the second end cap 132. The first current collector 150 is then supported by a support portion 1. 53. Apply a certain pressure to make the second current collector 170 fit with the second end cap 132. Weld the second seal 180, the second end cap 132 and the second current collector 170 together through laser penetration welding process from the second seal 180 to complete the electrical connection between the second end cap 132 and the second current collector 170. After welding, place the single cell 100 upright and inject liquid through the injection hole 1531. After liquid injection, assemble the first seal 160 and the first current collector 150 together. Weld the first seal 160 and the first current collector 150 together to the terminal post 140 from the first seal 160 to complete the superimposed welding of the first seal 160, the first current collector 150 and the terminal post 140, realize the overall sealing of the single cell 100, and realize the electrical connection between the first current collector 150 and the terminal post 140, and finally complete the assembly of the single cell 100.

[0143] On the other hand, in the embodiments of this application, this application also provides a battery pack, including: a housing; a single battery 100 as in any of the above embodiments and a housing cover, wherein the single battery 100 is disposed in the housing, the housing cover is connected to the housing, and the housing cover seals the housing.

[0144] The battery pack can be a three-tiered system consisting of individual cells 100, battery modules, and a battery pack. This means the individual cells 100 are first grouped into battery modules, and then the battery modules are placed inside a housing to form the battery pack. Alternatively, it can be a two-tiered system consisting of individual cells 100 and a battery pack, where the individual cells 100 are directly housed within a housing to form the battery pack. No specific limitations are imposed in this application; the design can be tailored to the specific circumstances, as long as it does not affect the effectiveness of this application.

[0145] The above steps are provided only to help understand the method, structure, and core ideas of this application. Those skilled in the art can make various improvements and modifications to this application without departing from its principles, and these improvements and modifications also fall within the scope of protection of the claims.

Claims

1. A single-cell battery having an axial orientation, characterized in that, include: The shell has a receiving cavity; Electrode assembly is disposed in the receiving cavity; The first end cap is connected to one end of the housing in the axial direction; An electrode post is inserted through the first end cap along the axial direction, and the electrode post and the first end cap are insulated from each other. A first current collector element, comprising: a first current collector portion and a first protrusion portion, the first current collector portion being disposed between the first end cap and the electrode assembly, and electrically connected to the electrode assembly; the first protrusion portion protruding from the first current collector portion on the side away from the electrode assembly, and passing through the electrode post along the axial direction, the first protrusion portion being electrically connected to the electrode post; and the first protrusion portion having a first through hole extending along the axial direction. A first sealing element is disposed in the first through hole and blocks the first through hole. Both the first sealing element and the first protrusion are welded to the pole post.

2. The single-cell battery as described in claim 1, characterized in that, The pole post is provided with a second through hole that extends along the axial direction, and the first protrusion is embedded in the second through hole; The first seal has a welding groove on the side away from the electrode assembly. The welding groove has a first groove wall extending along the axial direction. The first seal and the first protrusion are welded together to the electrode post from the first groove wall.

3. The single-cell battery as described in claim 1, characterized in that, The first current collector further includes a support portion disposed on the side of the first through hole near the electrode assembly, and the support portion is connected to the hole wall of the first through hole, and the side of the support portion opposite to the electrode assembly abuts against the first seal.

4. The single-cell battery as described in claim 3, characterized in that, The support portion has an injection hole that extends along the axial direction and is connected to the receiving cavity.

5. The single-cell battery as described in claim 1, characterized in that, The first current collector element further includes: a second protrusion, which protrudes from the side of the first current collector away from the electrode assembly, and the second protrusion is connected to the outer wall surface of the first protrusion, and the second protrusion and the electrode post are spaced apart in the axial direction.

6. The single-cell battery as described in claim 5, characterized in that, The individual battery cell also has a circumferential orientation around the axis; The first current collection part includes: a plurality of reinforcing parts and a plurality of welding parts, wherein each of the reinforcing parts and each of the welding parts is alternately arranged around the outer edge of the second protrusion in the circumferential direction.

7. The single-cell battery as described in claim 6, characterized in that, The individual cell also has a radial direction perpendicular to the axis; Each of the reinforcing portions extends along the radial direction, and in the radial direction, along the direction from the first protrusion toward the second protrusion, the thickness of each of the reinforcing portions gradually decreases in the axial direction.

8. The single-cell battery as described in claim 1, characterized in that, The pole post is provided with a second through hole that extends along the axial direction, and the first protrusion is embedded in the second through hole; The first seal has an end wall on the side away from the electrode assembly, and the first seal and the first protrusion are welded together to the electrode post from the end wall.

9. The single-cell battery as described in claim 1, characterized in that, The electrode post has a second through hole extending along the axial direction, and the electrode post has a first fixing groove on the side near the electrode assembly. The first protrusion is embedded in the first fixing groove, the side of the first seal away from the electrode assembly is embedded in the second through hole, and the side of the first seal close to the electrode assembly is disposed in the first through hole. The first seal has a welding groove on the side away from the electrode assembly. The welding groove has a first groove wall extending along the axial direction. The first seal and the first protrusion are welded together to the electrode post from the first groove wall.

10. The single-cell battery as described in claim 9, characterized in that, The first fixing groove extends along the axial direction, and the first fixing groove has a second groove wall on the side away from the electrode assembly in the axial direction. The first protrusion and the second groove wall are spaced apart in the axial direction, and the pole post and the first current collector are spaced apart in the axial direction.

11. The single-cell battery as described in claim 1, characterized in that, Also includes: The second end cap is disposed on the side of the housing away from the first end cap in the axial direction, and the second end cap has a third through hole that extends along the axial direction. A second current collector element is disposed in the receiving cavity and between the second end cap and the electrode assembly. The second current collector element is electrically connected to both the electrode assembly and the second end cap. The second sealing element is embedded in the third through hole and blocks the third through hole.

12. The single-cell battery as described in claim 11, characterized in that, The second end cap includes: a cover body and a third protrusion. The cover body is disposed on the side of the housing away from the first end cap in the axial direction. The third protrusion protrudes from the cover body on the side close to the electrode assembly, and a through third hole is formed on the third protrusion. The second current collecting element includes a second current collecting portion and a fourth protrusion. The second current collecting portion is disposed between the second end cap and the electrode assembly, and the second current collecting portion is electrically connected to the electrode assembly. The fourth protrusion protrudes from the side of the second current collecting portion away from the electrode assembly, and a second fixing groove is formed on the side of the fourth protrusion away from the second current collecting portion. The third protrusion is embedded in the second fixing groove, and the third protrusion is electrically connected to the fourth protrusion.

13. The single-cell battery as described in claim 12, characterized in that, Along the axial direction, the third protrusion is spaced apart from the second collection portion, and the fourth protrusion is spaced apart from the cover portion.

14. A battery pack, characterized in that, include: Box; The single-cell battery as described in any one of claims 1 to 13, wherein the single-cell battery is disposed within the housing; as well as A lid, which is connected to the box body and covers the box body.

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