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 provided with a containing cavity; an electrode assembly arranged in the containing cavity; a top cover connected to one side of the shell in a first direction and covering the containing cavity, and the top cover is provided with a liquid injection hole; and an insulation member, the insulation member comprises: an insulation main body, a plurality of flow guide portions and a plurality of first flow blocking portions, the insulation main body is provided with a through hole, and the through hole is communicated with the liquid injection hole; the plurality of flow guide portions are arranged around the outer periphery of the through hole to form a flow guide channel with an opening, the flow guide channel is communicated with the through hole, and the opening communicates the flow guide channel with the containing cavity; and the first flow blocking portion blocks part of the opening. According to the present application, the tab of the electrode assembly is prevented from extending into the through hole and contacting the top cover to cause short circuit of the single battery, the short circuit risk between the electrode assembly and the top cover is reduced, and the safety performance of the single battery is ensured.

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] 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. Summary of the Invention

[0003] Embodiments of this application provide a single battery cell and a battery pack to improve the safety performance of the single battery cell.

[0004] To address the aforementioned technical problems, embodiments of this application disclose the following technical solutions:

[0005] On one hand, a single-cell battery is provided, having a first direction and a reference plane perpendicular to the first direction, including: a housing having a receiving cavity;

[0006] Electrode assembly, disposed within the receiving cavity;

[0007] A top cover, connected to one side of the housing in the first direction and sealing the receiving cavity, and having an injection hole on the top cover; and

[0008] An insulating component includes: an insulating body, multiple flow guides, and multiple first flow blocking parts. The insulating body is connected to the top cover near the electrode assembly and has a through hole that communicates with an injection hole. Multiple flow guides are connected to the insulating body near the electrode assembly and surround the through hole to form an open flow channel that communicates with the through hole and the opening connects the flow channel to a receiving cavity. Adjacent flow guides are spaced apart to form a first flow opening between them, which connects the flow channel to the receiving cavity. Each first flow blocking part is connected to a flow guide near the electrode assembly, and adjacent first flow blocking parts are spaced apart, with each first flow blocking part blocking at least part of the opening.

[0009] The orthographic projection area of ​​each first flow-blocking section on the reference plane is S1 mm. 2 The orthographic projection area of ​​the hole wall on the reference plane is S² mm. 2 The condition is satisfied that 0.0002≤S1 / S2≤0.28.

[0010] In addition to one or more of the features disclosed above, or alternatively, the orthographic projection area S1 mm of each first flow-blocking portion on the reference plane2 The orthographic projection area of ​​the hole wall on the reference plane is S2mm. 2 It also satisfies: 0.04≤S1 / S2≤0.2.

[0011] In addition to one or more of the features disclosed above, or alternatively, the orthographic projection area S1 mm of each first flow-blocking portion on the reference plane 2 It also satisfies: 0.051≤S1≤71.245; and / or,

[0012] The orthographic projection area of ​​the hole wall on the reference plane is S2 mm. 2 It also satisfies: 7.065≤S2≤254.34.

[0013] In addition to one or more of the features disclosed above, or alternatively, the through-hole has a radial direction perpendicular to the first direction; the first baffle has a radial dimension of L1 mm, and the maximum profile dimension of the through-hole is D mm, satisfying: 0.01 ≤ L1 / D ≤ 0.47; or,

[0014] The radial dimension L1 mm of the first baffle and the maximum profile dimension D mm of the through hole also satisfy: 0.06≤L1 / D≤0.18.

[0015] In addition to one or more of the features disclosed above, or alternatively, the radial dimension L1 mm of the first baffle also satisfies: 0.03 ≤ L1 ≤ 8.46; and / or,

[0016] The maximum outline dimension D mm of the through hole also satisfies: 3≤D≤18.

[0017] In addition to one or more of the features disclosed above, or alternatively, the radial dimension L1 mm of the first baffle also satisfies: 0.36 ≤ L1 ≤ 2.16; and / or,

[0018] The maximum outline dimension D mm of the through hole also satisfies: 6≤D≤12.

[0019] In addition to one or more of the features disclosed above, or as an alternative, the through hole has a central axis extending along a first direction, and the radius of the through hole intersects the central axis;

[0020] Multiple flow guides are arranged symmetrically about the central axis, and multiple first flow baffles are arranged symmetrically about the central axis.

[0021] In addition to one or more of the features disclosed above, or alternatively, the guide portion extends along the first direction; or,

[0022] The flow guide is inclined relative to the first direction, and in the first direction, along the direction of the insulating member toward the electrode assembly, the distance between the flow guide and the central axis of the through hole decreases.

[0023] In addition to one or more of the features disclosed above, or as an alternative, the through hole has a hole wall;

[0024] The insulating component also includes: a plurality of second flow-blocking parts, each of which is connected to the hole wall and is disposed within the through hole, with each second flow-blocking part disposed between two adjacent flow-guiding parts.

[0025] In addition to one or more of the features disclosed above, or alternatively, the orthographic projection area of ​​each second baffle on the reference plane is S3 mm. 2 The condition is satisfied that: 0.0002 ≤ S3 / S2 ≤ 0.15; or,

[0026] The projected area of ​​each second flow baffle on the reference plane is S3 mm. 2 The condition is satisfied that: 0.021≤S3 / S2≤0.097.

[0027] In addition to one or more of the features disclosed above, or alternatively, the orthographic projection area of ​​each second baffle on the reference plane is S3 mm. 2 It also satisfies: 0.046≤S3≤38.151.

[0028] In addition to one or more of the features disclosed above, or alternatively, the second baffle extends radially along the hole wall toward the center of the through hole;

[0029] The radial dimension of the second baffle is L2 mm, satisfying: 0.017 ≤ L2 / D ≤ 0.47; or,

[0030] The radial dimension L2 mm of the second baffle also satisfies: 0.06≤L2 / D≤0.18.

[0031] In addition to one or more of the features disclosed above, or alternatively, the radial dimension L2 mm of the second baffle also satisfies: 0.051 ≤ L2 ≤ 8.46; or,

[0032] The radial dimension L2 mm of the second baffle also satisfies: 0.36≤L2≤2.16.

[0033] In addition to one or more of the features disclosed above, or alternatively, the single cell also has a second direction intersecting the first direction;

[0034] The insulating component also includes: a pressure relief boss, which protrudes from the insulating body on the side near the electrode assembly, and the pressure relief boss and the through hole are spaced apart in the second direction;

[0035] The distance between the pressure relief boss and the through hole is T2 mm, and the dimension of the insulating body in the second direction is T1 mm, satisfying: 0.005≤T2 / T1≤0.833.

[0036] In addition to one or more of the features disclosed above, or alternatively, the distance T2 mm between the pressure relief boss and the through hole also satisfies: 3 ≤ T2 ≤ 500; and / or,

[0037] The dimension T1 mm of the insulating body in the second direction also satisfies: 10≤T1≤600.

[0038] In addition to one or more of the features disclosed above, or as an alternative, the single cell also includes: a terminal post disposed on the top cover, with a portion of the terminal post passing through the insulating body and electrically connected to the electrode assembly, and a through hole located between the terminal post and the pressure relief boss;

[0039] The distance between the pole and the through hole is T3 mm, which satisfies: 0.0067≤T3 / T1≤0.833.

[0040] In addition to one or more of the features disclosed above, or alternatively, the distance T3mm between the pole and the through hole also satisfies: 4≤T3≤500.

[0041] 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; and individual cells as described in any of the preceding claims, the individual cells being disposed within the housing.

[0042] One of the above technical solutions has the following advantages or beneficial effects: This application provides a first baffle on the side of the flow guide near the electrode assembly to block part of the opening. Simultaneously, by limiting the ratio of the radial dimension L1 mm of the first baffle to the maximum outline dimension D mm of the through hole to within the range of 0.01 to 1.67, the electrolyte injection efficiency of the single cell is guaranteed. At the same time, the first baffle effectively blocks and buffers the electrolyte, reducing direct impact of the electrolyte on the electrode assembly during electrolyte injection, thereby reducing the shedding of active materials from the positive and negative electrode plates in the electrode assembly and reducing safety hazards of the single cell. Furthermore, the first baffle efficiently shields the overlapping area of ​​the top cover and the through hole, preventing the electrode tabs of the electrode assembly from extending into the through hole and contacting the top cover, thus preventing a short circuit in the single cell and reducing the risk of a short circuit between the electrode assembly and the top cover, ensuring the safety performance of the single cell. Attached Figure Description

[0043] 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.

[0044] Figure 1 This is a three-dimensional structural view of a single battery cell provided according to an embodiment of this application;

[0045] Figure 2 This is an exploded structural view of a single battery cell provided according to an embodiment of this application;

[0046] Figure 3 This is an exploded structural view of the top cover and insulating components provided according to an embodiment of this application;

[0047] Figure 4 This is an exploded structural view of the top cover and insulating components provided according to an embodiment of this application;

[0048] Figure 5 This is a bottom view of the top cover and insulating components provided according to an embodiment of this application;

[0049] Figure 6 This is a bottom view of the insulating member provided according to an embodiment of this application;

[0050] Figure 7 yes Figure 6 A magnified view of a section at point B in the middle;

[0051] Figure 8 This is a cross-sectional view along the AA direction of the insulating member provided according to an embodiment of this application;

[0052] Figure 9 yes Figure 8 A magnified view of a section at point C;

[0053] Figure 10 This is a schematic diagram of the battery pack structure provided according to an embodiment of this application.

[0054] Explanation of reference numerals in the attached figures:

[0055] 100. Single cell battery;

[0056] 110. Shell; 111. Receiving cavity;

[0057] 120. Electrode assembly;

[0058] 130. Top cover; 131. Injection port;

[0059] 140. Insulating component; 141. Insulating body; 1411. Through hole; 1412. Hole wall; 142. Flow guide; 1421. Flow guide channel; 1422. Opening; 1423. First flow guide port; 143. First flow baffle; 144. Second flow baffle; 145. Pressure relief boss;

[0060] 150, pole;

[0061] 160. Pressure relief valve;

[0062] 200. Box body;

[0063] 300. Box lid. Detailed Implementation

[0064] 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.

[0065] 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.

[0066] 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.

[0067] 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.

[0068] Current secondary battery filling processes typically involve injecting electrolyte directly into the battery through filling holes and lower plastic through-holes using filling equipment. However, in actual production, to improve process efficiency and ensure the battery cells are fully filled with electrolyte, higher injection pressures are usually used. Due to the high injection pressure and the lack of flow obstruction during electrolyte injection, the electrolyte flowing in through the filling holes and lower plastic through-holes directly impacts the positive and negative electrode plates and separator inside the secondary battery, damaging the internal structure and affecting the battery's yield and safety performance.

[0069] To address the aforementioned problems, in the embodiments of this application, reference is made to... Figures 1 to 9 This application provides a single-cell battery 100, which has a first direction Z, a second direction X, and a third direction Y that intersect each other in pairs. For example, the single-cell battery 100 has a first direction Z, a second direction X, and a third direction Y that are perpendicular to each other in pairs. Here, "perpendicular" refers to a state where the angle formed by a straight line and a straight line, a straight line and a plane, or a plane and a plane is 89° to 91°.

[0070] Specifically, the single cell 100 includes: a casing 110, an electrode assembly 120, a top cover 130, and an insulating component 140.

[0071] Specifically, the housing 110 is provided with a receiving cavity 111; the electrode assembly 120 is disposed in the receiving cavity 111; the top cover 130 is connected to one side of the housing 110 in the first direction Z, the top cover 130 covers the receiving cavity 111, and the top cover 130 is provided with a liquid injection hole 131; the insulating member 140 is disposed in the receiving cavity 111, and the insulating member 140 is connected to the side of the top cover 130 near the electrode assembly 120.

[0072] 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.

[0073] The individual battery cell 100 can be a prismatic battery, a pouch battery, or a battery of other shapes. For example, in this application, the individual battery cell 100 is a square battery.

[0074] The housing 110 may be made of a strong material such as metal, but is not limited to this. For example, the housing 110 described above is made of aluminum profile, but is not limited to this.

[0075] The top cover 130 can be integrally formed with the housing 110, meaning the top cover 130 can serve as the outer wall of the housing 110. The top cover 130 can also be fixedly connected to the housing 110, for example, by welding or other processes, to one end of the housing 110 in the Z-axis direction. This application does not impose specific limitations and can be configured according to actual circumstances. For example, in this application, the top cover 130 and the housing 110 are separate components, and the top cover 130 and the housing 110 are fixed together by welding.

[0076] The insulating component 140 can be made of rubber, silicone, or plastic, but is not limited to these materials.

[0077] The single-cell battery 100 also includes an electrolyte, electrode posts 150, 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 or stacking a positive electrode sheet, a separator, and a negative electrode sheet. 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, and the tabs are electrically connected to the electrode posts 150 to form a current loop, enabling the single-cell battery 100 to function normally.

[0078] Specifically, the insulating component 140 includes: an insulating body 141, a plurality of flow guiding portions 142, and a plurality of first flow blocking portions 143. The insulating body 141 is connected to the side of the top cover 130 near the electrode assembly 120. The insulating body 141 has a through hole 1411, which communicates with the liquid injection hole 131. The plurality of flow guiding portions 142 are all connected to the side of the insulating body 141 near the electrode assembly 120, and the plurality of flow guiding portions 142 surround the outer periphery of the through hole 1411 to form a flow guiding channel 1421 with an opening 1422. 1421 is connected to the through hole 1411, and the opening 1422 connects the flow channel 1421 to the receiving cavity 111; two adjacent flow sections 142 are spaced apart to form a first flow port 1423 between the two adjacent flow sections 142, and the first flow port 1423 connects the flow channel 1421 to the receiving cavity 111; each first flow blocking section 143 is connected to a flow section 142 on the side near the electrode assembly 120, and two adjacent first flow blocking sections 143 are spaced apart and the first flow blocking section 143 blocks at least part of the opening 1422.

[0079] The insulating body 141 and the flow guiding part 142 can be integrally formed, meaning they are a single structure. Alternatively, the insulating body 141 and the flow guiding part 142 can be separately configured and fixedly connected to each other. For example, the flow guiding part 142 is fixedly connected to the insulating body 141 using a snap-fit ​​or similar process. This application does not impose specific limitations and can be configured according to actual circumstances. For example, in this application, the insulating body 141 and the flow guiding part 142 are integrally injection molded.

[0080] The first flow-blocking portion 143 and the flow-guiding portion 142 can be integrally formed, that is, the first flow-blocking portion 143 and the flow-guiding portion 142 are a single-piece structure; alternatively, the first flow-blocking portion 143 and the flow-guiding portion 142 can be separately arranged and fixedly connected to each other. For example, the first flow-blocking portion 143 is fixedly connected to the flow-guiding portion 142 by a snap-fit ​​or other process. This application does not impose specific limitations and can be configured according to actual circumstances. For example, in this application, the first flow-blocking portion 143 and the flow-guiding portion 142 are integrally injection molded.

[0081] The individual cell also has a reference plane (not shown) perpendicular to the first direction Z. Along the first direction Z, the orthographic projection of the first flow-blocking part 143 on the reference plane at least partially coincides with the orthographic projection of the inner wall of the opening 1422 on the reference plane, that is, at least part of the first flow-blocking part 143 is located inside the opening 1422.

[0082] The through hole 1411 can be of any shape. For example, in this application, the through hole 1411 is circular to facilitate the processing and shaping of the through hole 1411.

[0083] Understandably, during electrolyte injection into the single cell 100, the electrolyte flows from the injection hole 131 to the through hole 1411, and then from the through hole 1411 to the guide channel 1421. A portion of the electrolyte in the guide channel 1421 flows from the opening 1422 into the receiving cavity 111, while another portion flows from the first guide port 1423 into the receiving cavity 111. This guide flow further reduces the direct impact of the electrolyte on the electrode assembly 120 during injection, thereby reducing the shedding of active materials from the positive and negative electrode plates in the electrode assembly 120 and minimizing safety hazards of the single cell 100. Simultaneously, this application utilizes the guide section 142... A first baffle 143 is provided on the side near the electrode assembly 120 to block part of the opening 1422, thereby reducing the direct impact of the electrolyte on the electrode assembly 120 during electrolyte injection of the single cell 100. This reduces the shedding of active materials from the positive and negative electrode plates in the electrode assembly 120 and reduces the safety hazards of the single cell 100. At the same time, the first baffle 143 can effectively block the overlapping area of ​​the top cover 130 and the through hole 1411, preventing the electrode tabs of the electrode assembly 120 from extending into the through hole 1411 and contacting the top cover 130, thus preventing a short circuit in the single cell 100. This reduces the risk of a short circuit between the electrode assembly 120 and the top cover 130 and ensures the safety performance of the single cell 100.

[0084] Specifically, the single cell 100 also has a reference plane O perpendicular to the first direction Z. For example, in this application, the reference plane O can be an outer surface of the top cover 130 perpendicular to the first direction Z, but is not limited thereto.

[0085] The orthographic projection area of ​​each first flow-blocking section 143 on the reference plane O is S1 mm. 2 The orthographic projection area of ​​the hole wall of through hole 1411 on the reference plane O is S2 mm. 2 The condition is satisfied that 0.0002 ≤ S1 / S2 ≤ 0.28. That is, the orthogonal projection area S1 mm of each first baffle 143 on the reference plane O. 2 The orthographic projection area S2 mm of the hole wall of through hole 1411 on reference plane O 2 The ratio can be controlled within the range of 0.0002 to 0.28. For example, S1 / S2 can be a range of one or any two of the following: 0.0002, 0.02, 0.04, 0.06, 0.08, 0.1, 0.12, 0.14, 0.16, 0.18, 0.2, 0.22, 0.24, 0.26, or 0.28. The specific values ​​of S1 / S2 given above are merely illustrative; any value within the range of 0.0002 to 0.28 is within the scope of protection of this application.

[0086] This application defines the orthographic projection area S1 mm of each first baffle portion 143 on the reference plane O. 2 The orthographic projection area S2 mm of the hole wall of through hole 1411 on reference plane O 2 The ratio is in the range of 0.0002 to 0.28, so that the structural dimensions between the first baffle 143 and the through hole 1411 are reasonably designed to ensure the electrolyte injection efficiency of the single cell 100. At the same time, it ensures that the first baffle 143 can effectively block and buffer the electrolyte, reducing the direct impact of the electrolyte on the electrode assembly 120 during electrolyte injection, thereby reducing the shedding of active materials on the positive and negative electrode plates in the electrode assembly 120 and reducing the safety hazards of the single cell 100. At the same time, it ensures that the first baffle 143 can effectively shield the overlapping area of ​​the top cover 130 and the through hole 1411, preventing the electrode tab of the electrode assembly 120 from extending into the through hole 1411 and contacting the top cover 130, causing a short circuit in the single cell 100, reducing the short circuit risk between the electrode assembly 120 and the top cover 130, and ensuring the safety performance of the single cell 100.

[0087] Among them, the orthographic projection area of ​​each first flow-blocking part 143 on the reference plane O is S1 mm. 2 The actual single cell 100 can be disassembled, and the image area of ​​any one of the first current-blocking parts 143 of the insulating component 140 can be measured multiple times using a projection measurement device (such as a digital microscope or image measuring instrument) to obtain the orthographic projection area S1 mm of each first current-blocking part 143 on the reference plane O. 2 However, it is not limited to this.

[0088] The orthographic projection area of ​​the hole wall of through hole 1411 on the reference plane O is S2 mm. 2 The actual single cell 100 can be disassembled, and the image area of ​​the hole wall of the through hole 1411 of the insulating component 140 can be measured multiple times using a projection measurement device (such as a digital microscope or image measuring instrument). This allows the orthogonal projection area S2mm of the hole wall of the through hole 1411 onto the reference plane O to be obtained. 2 However, it is not limited to this.

[0089] The wall of the through hole 1411 is only the inner wall that surrounds the through hole 1411, and does not include the outer wall surface of other structures. In one embodiment, the orthographic projection area of ​​each first baffle 143 on the reference plane O is S1 mm. 2 The orthographic projection area S2 mm of the hole wall of through hole 1411 on reference plane O 2 It also satisfies: 0.04≤S1 / S2≤0.2. That is, the orthogonal projection area S1 mm of each of the first flow-blocking parts 143 on the reference plane O. 2 The orthographic projection area S2 mm of the hole wall of through hole 1411 on reference plane O2 The ratio can be controlled within the range of 0.04 to 0.2. For example, S1 / S2 can be a range of one or any two of the following: 0.04, 0.06, 0.08, 0.1, 0.12, 0.14, 0.16, 0.18, or 0.2. The specific values ​​of S1 / S2 given above are merely illustrative; any value within the range of 0.04 to 0.2 is within the scope of protection of this application.

[0090] This application defines the orthographic projection area S1 mm of each first baffle portion 143 on the reference plane O. 2 The orthographic projection area S2 mm of the hole wall of through hole 1411 on reference plane O 2 The ratio can be controlled within the range of 0.04 to 0.2 to further optimize the structural dimensions between the first baffle 143 and the through hole 1411, thereby ensuring the electrolyte injection efficiency of the single cell 100. Simultaneously, it further ensures that the first baffle 143 can effectively block and buffer the electrolyte, reducing the direct impact of the electrolyte on the electrode assembly 120 during electrolyte injection, thus reducing the shedding of active materials from the positive and negative electrode plates in the electrode assembly 120 and minimizing safety hazards of the single cell 100. Furthermore, it ensures that the first baffle 143 can efficiently shield the overlapping area of ​​the top cover 130 and the through hole 1411, preventing the electrode tabs of the electrode assembly 120 from extending into the through hole 1411 and contacting the top cover 130, thus reducing the short circuit risk between the electrode assembly 120 and the top cover 130 and ensuring the safety performance of the single cell 100.

[0091] For example, in this application, the orthographic projection of each first flow-blocking portion 143 on the reference plane O is fan-shaped, and the central angle of each first flow-blocking portion 143 is 65°.

[0092] In one embodiment, the orthographic projection area of ​​each first baffle 143 on the reference plane O is S1 mm. 2 It also satisfies: 0.051≤S1≤71.245. That is, the orthogonal projection area S1 mm of each of the first flow-blocking parts 143 on the reference plane O. 2 It can be controlled within 0.051mm 2 ~71.245mm 2 Within the range. For example, S1 can be 0.051 mm. 2 5mm 2 10mm 2 15mm 2 20mm 2 25mm 2 30mm 2 35mm 2 40mm 2 45mm2 50mm 2 55mm 2 60mm 2 65mm 2 70mm 2 Or 71.245mm 2 The range of one or any two of them. The specific values ​​of S1 given above are merely illustrative, as long as they are within 0.051 mm. 2 ~71.245mm 2 Any value within the range is within the protection scope of this application. This application defines the orthographic projection area S1 mm of each first flow-blocking part 143 on the reference plane O. 2 At 0.051mm 2 ~71.245mm 2 Within the specified range, this ensures the electrolyte injection efficiency of the single cell 100; simultaneously, it further ensures that the first baffle 143 can effectively block and buffer the electrolyte, reducing the direct impact of the electrolyte on the electrode assembly 120 during electrolyte injection, thereby reducing the shedding of active materials on the positive and negative electrode plates in the electrode assembly 120 and reducing the safety hazards of the single cell 100; at the same time, it ensures that the first baffle 143 can effectively block the overlapping area of ​​the top cover 130 and the through hole 1411, preventing the electrode tabs of the electrode assembly 120 from extending into the through hole 1411 and contacting the top cover 130, causing a short circuit in the single cell 100, reducing the risk of short circuit between the electrode assembly 120 and the top cover 130, and ensuring the safety performance of the single cell 100.

[0093] The orthographic projection area of ​​the hole wall of through hole 1411 on the reference plane O is S2 mm. 2 It also satisfies: 7.065≤S2≤254.34. That is, the orthographic projection area S2 mm of the hole wall of through hole 1411 on the reference plane O. 2 It can be controlled at 7.065mm 2 ~254.34mm 2 Within the range. For example, S2 mm 2 It can be 7.065mm. 2 20mm 2 40mm 2 60mm 2 80mm 2 100mm 2 120mm 2 140mm 2 160mm 2 180mm 2 200mm 2 220mm 2 240mm 2250mm 2 Or 254.34mm 2 The range consisting of one or any two of them. S2 mm 2 The specific values ​​mentioned above are merely illustrative examples; as long as it is within 0.317mm... 2 ~13.176mm 2 Any value within the range is within the protection scope of this application. This application defines the orthographic projection area S2 mm of the hole wall of the through hole 1411 onto the reference plane O. 2 At 7.065mm 2 ~254.34mm 2 Within the specified range, the structural dimensions of the through hole 1411 are designed reasonably to further ensure the efficient flow of electrolyte through the through hole 1411 during the electrolyte injection of the single cell 100, thereby ensuring the electrolyte injection efficiency of the single cell 100.

[0094] In one embodiment, the orthographic projection area of ​​each first baffle 143 on the reference plane O is S1 mm. 2 It can be controlled within 0.28mm 2 ~50.87mm 2 Within the range.

[0095] In one embodiment, in order to ensure both the electrolyte injection efficiency and the safety performance of the single cell 100, reference is made in this application. Figures 6 to 7 The through hole 1411 has a radial direction P perpendicular to the first direction Z; the first baffle portion 143 has a dimension L1 mm in the radial direction P, and the maximum outline dimension of the through hole 1411 is D mm, satisfying: 0.01≤L1 / D≤0.47. That is, the ratio of the dimension L1 mm of the first baffle portion 143 in the radial direction P to the maximum outline dimension D mm of the through hole 1411 can be controlled within the range of 0.01 to 0.47. For example, L1 / D can be one of 0.01, 0.05, 0.1, 0.15, 0.2, 0.25, 0.3, 0.35, 0.4, or 0.47, or any combination of two of them. The specific values ​​of L1 / D given above are only illustrative examples, and any value within the range of 0.01 to 0.47 is within the protection scope of this application.

[0096] The dimension L1 mm of the first current-blocking part 143 in the radial direction P can be obtained by disassembling the actual single cell 100 and measuring the length of the first current-blocking part 143 on the insulating member 140 against the radial direction P multiple times using a measuring tool, and then 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.

[0097] The maximum outline dimension D mm of the through hole 1411 can be obtained by disassembling the actual single cell 100 and measuring the diameter of the through hole 1411 on the insulating component 140 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 these.

[0098] Understandably, this application limits the ratio of the radial dimension L1 mm of the first flow-blocking part 143 to the maximum outline dimension D mm of the through hole 1411 to be within the range of 0.01 to 0.47, so as to reasonably design the structural dimensions between the first flow-blocking part 143 and the through hole 1411, thereby ensuring the electrolyte injection efficiency of the single cell 100; at the same time, it ensures that the first flow-blocking part 143 can effectively block and buffer the electrolyte, reducing the direct impact of the electrolyte on the electrode assembly 120 during electrolyte injection, thereby reducing the shedding of active materials on the positive and negative electrode plates in the electrode assembly 120 and reducing the safety hazards of the single cell 100; at the same time, it ensures that the first flow-blocking part 143 can effectively shield the overlapping area of ​​the top cover 130 and the through hole 1411, preventing the electrode tab of the electrode assembly 120 from extending into the through hole 1411 and contacting the top cover 130, causing a short circuit in the single cell 100, reducing the short circuit risk between the electrode assembly 120 and the top cover 130, and ensuring the safety performance of the single cell 100.

[0099] Furthermore, the radial dimension L1 mm of the first flow-blocking portion 143 and the maximum outline dimension D mm of the through hole 1411 also satisfy: 0.06 ≤ L1 / D ≤ 0.18. That is, the ratio of the radial dimension L1 mm of the first flow-blocking portion 143 to the maximum outline dimension D mm of the through hole 1411 can be controlled within the range of 0.06 to 0.18. For example, L1 / D can be one or any combination of two of the following: 0.06, 0.07, 0.08, 0.09, 0.1, 0.11, 0.12, 0.13, 0.14, 0.15, 0.16, 0.17, or 0.18. The specific values ​​of L1 / D given above are merely illustrative, and any value within the range of 0.06 to 0.18 is within the protection scope of this application. This application limits the ratio of the radial dimension L1 mm of the first flow-blocking part 143 to the maximum outline dimension D mm of the through hole 1411 to be within the range of 0.06 to 0.18, so as to further optimize the structural dimensions between the first flow-blocking part 143 and the through hole 1411. This ensures better liquid injection efficiency of the single cell 100 while ensuring that the first flow-blocking part 143 can effectively block the overlapping area of ​​the top cover 130 and the through hole 1411, thereby preventing the electrode tab of the electrode assembly 120 from extending into the through hole 1411 and contacting the top cover 130, which would cause a short circuit in the single cell 100. This reduces the risk of short circuit between the electrode assembly 120 and the top cover 130 and ensures the safety performance of the single cell 100.

[0100] In one embodiment, in order to ensure the safety performance of the single cell 100, reference is made in this application. Figures 6 to 7 The first flow-blocking portion 143, with a radial dimension L1 mm in the direction P, also satisfies the condition: 0.03 ≤ L1 ≤ 8.46. That is, the radial dimension L1 mm of the first flow-blocking portion 143 in the direction P can be controlled within the range of 0.03 mm to 8.46 mm. For example, L1 mm can be any one of 0.03 mm, 1 mm, 2 mm, 3 mm, 4 mm, 5 mm, 6 mm, 7 mm, 8 mm, or 8.46 mm, or any combination thereof. The specific values ​​of L1 mm given above are merely illustrative; any value within the range of 0.03 mm to 8.46 mm is within the scope of protection of this application. This application limits the radial dimension L1 mm of the first flow-blocking part 143 to within the range of 0.03 mm to 8.46 mm to further optimize the structural dimensions of the first flow-blocking part 143. This ensures that the first flow-blocking part 143 can effectively block and buffer the electrolyte, reducing the direct impact of the electrolyte on the electrode assembly 120 during electrolyte injection of the single cell 100. This reduces the shedding of active materials from the positive and negative electrode plates in the electrode assembly 120, thereby reducing the safety hazards of the single cell 100. It also ensures that the first flow-blocking part 143 can effectively shield the overlapping area of ​​the top cover 130 and the through hole 1411, preventing the electrode tabs of the electrode assembly 120 from extending into the through hole 1411 and contacting the top cover 130, thus preventing a short circuit in the single cell 100. This reduces the risk of a short circuit between the electrode assembly 120 and the top cover 130, ensuring the safety performance of the single cell 100.

[0101] Furthermore, the radial dimension L1 mm of the first baffle 143 on P also satisfies: 0.36 ≤ L1 ≤ 2.16. That is, the radial dimension L1 mm of the first baffle 143 on P can be controlled within the range of 0.36 mm to 2.16 mm. For example, L1 mm can be one or any combination of 0.36 mm, 0.4 mm, 0.6 mm, 0.8 mm, 1 mm, 1.2 mm, 1.4 mm, 1.6 mm, 1.8 mm, 1.2 mm, or 2.16 mm. The specific values ​​of L1 mm given above are merely illustrative examples, and any value within the range of 0.36 mm to 2.16 mm is within the protection scope of this application. This application limits the radial dimension L1mm of the first flow-blocking part 143 to within the range of 0.36mm to 2.16mm to further optimize the structural dimensions of the first flow-blocking part 143. This ensures that the first flow-blocking part 143 can effectively block and buffer the electrolyte, reducing the direct impact of the electrolyte on the electrode assembly 120 during electrolyte injection of the single cell 100. This reduces the shedding of active materials from the positive and negative electrode plates in the electrode assembly 120, thereby reducing the safety hazards of the single cell 100. It also ensures that the first flow-blocking part 143 can effectively shield the overlapping area of ​​the top cover 130 and the through hole 1411, preventing the electrode tabs of the electrode assembly 120 from extending into the through hole 1411 and contacting the top cover 130, thus preventing a short circuit in the single cell 100. This reduces the risk of a short circuit between the electrode assembly 120 and the top cover 130, ensuring the safety performance of the single cell 100.

[0102] In one embodiment, in order to ensure a 100% electrolyte injection efficiency for a single cell, this application refers to... Figures 6 to 7 The maximum outline dimension D mm of the through hole 1411 also satisfies: 3 ≤ D ≤ 18. That is, the maximum outline dimension D mm of the through hole 1411 can be controlled within the range of 3 mm to 18 mm. For example, the maximum outline dimension D mm can be one or any combination of 3 mm, 4 mm, 5 mm, 6 mm, 7 mm, 8 mm, 9 mm, 10 mm, 11 mm, 12 mm, 13 mm, 14 mm, 15 mm, 16 mm, 17 mm, or 18 mm. The specific values ​​of the maximum outline dimension D mm mentioned above are only given as examples, and any value within the range of 3 mm to 18 mm is within the protection scope of this application. By limiting the maximum outline dimension D mm of the through hole 1411 to the range of 3 mm to 18 mm, this application reasonably designs the structural dimensions of the through hole 1411 to further ensure the efficient flow of electrolyte through the through hole 1411 during electrolyte filling of the single cell 100, thereby ensuring the electrolyte filling efficiency of the single cell 100.

[0103] Furthermore, the maximum outline dimension D mm of the through hole 1411 also satisfies: 6 ≤ D ≤ 12. That is, the maximum outline dimension D mm of the through hole 1411 can be controlled within the range of 6 mm to 12 mm. For example, the maximum outline dimension D mm can be one or a combination of any two of the following: 6 mm, 6.5 mm, 7 mm, 7.5 mm, 8 mm, 8.5 mm, 9 mm, 9.5 mm, 10 mm, 10.5 mm, 11 mm, 11.5 mm, or 12 mm. The specific values ​​of the maximum outline dimension D mm given above are merely illustrative examples, and any value within the range of 6 mm to 12 mm is within the protection scope of this application. This application further optimizes the structural dimensions of the through hole 1411 by limiting its maximum outline dimension D mm to the range of 6 mm to 12 mm. This ensures efficient electrolyte flow through the through hole 1411 during electrolyte filling of the single cell 100, thereby guaranteeing the electrolyte filling efficiency of the single cell 100. At the same time, it further prevents the electrode tabs of the electrode assembly 120 from extending into the through hole 1411 and contacting the top cover 130, thus reducing the risk of short circuit between the electrode assembly 120 and the top cover 130 and ensuring the safety performance of the single cell 100.

[0104] In one embodiment, a sealing element (not shown in the figure) is also provided at the injection hole 131 to seal the injection hole 131, thereby sealing the entire single cell 100 and ensuring the normal use of the single cell 100.

[0105] In one embodiment, the plurality of flow guides 142 and the plurality of first flow deflectors 143 may be arranged asymmetrically.

[0106] In another embodiment, reference Figures 6 to 7 The through hole 1411 has a central axis Q, which extends along the first direction Z, and the radii of the through hole 1411 intersect the central axis Q. Multiple flow guides 142 are symmetrically arranged about the central axis Q, and multiple first flow baffles 143 are symmetrically arranged about the central axis Q, so as to ensure that the electrolyte can flow quickly from the flow guide channel 1421 into the receiving cavity 111 when the single cell 100 is filled with electrolyte, thereby improving the electrolyte filling efficiency of the single cell 100 while ensuring the safety performance of the single cell 100. At the same time, it facilitates the processing and forming of the insulating component 140 and improves the production efficiency of the single cell 100.

[0107] In one embodiment, the flow guide 142 extends along the first direction Z to facilitate the processing and forming of the insulating member 140, thereby improving the production efficiency of the single cell 100.

[0108] In another embodiment, reference Figures 8 to 9The flow guide portion 142 is inclined relative to the first direction Z, and in the first direction Z, along the direction of the insulating member 140 toward the electrode assembly 120, the distance between the flow guide portion 142 and the central axis Q of the through hole 1411 is reduced, so that the flow guide channel 1421 is generally tapered, which improves the flow guide effect of the flow guide channel 1421 formed by the flow guide portion 142. At the same time, it further avoids the electrode tab of the electrode assembly 120 from extending into the through hole 1411 and contacting the top cover 130, causing a short circuit in the single cell 100, and reduces the risk of short circuit between the electrode assembly 120 and the top cover 130.

[0109] In one embodiment, to further ensure the safety performance of the single cell 100, reference is made in this application. Figures 6 to 7 The through hole 1411 has a hole wall 1412. The insulating member 140 also includes a plurality of second flow-blocking portions 144, each of which is connected to the hole wall 1412 and is disposed within the through hole 1411, with each second flow-blocking portion 144 disposed between two adjacent flow-guiding portions 142.

[0110] The insulating body 141 and the second current-blocking part 144 can be integrally formed, meaning they are a single, integrated structure. Alternatively, the insulating body 141 and the second current-blocking part 144 can be separately configured and fixedly connected to each other. For example, the second current-blocking part 144 is fixedly connected to the insulating body 141 using a snap-fit ​​or similar process. This application does not impose specific limitations and can be configured according to actual circumstances. For example, in this application, the insulating body 141 and the second current-blocking part 144 are integrally injection molded.

[0111] The single cell 100 also has a reference plane (not shown) perpendicular to the first direction Z. Along the first direction Z, the orthogonal projection of the second flow-blocking part 144 on the reference plane is located within the orthogonal projection of the hole wall 1412 of the through hole 1411 on the reference plane, that is, the second flow-blocking part 144 is located inside the through hole 1411.

[0112] Understandably, this application provides a second baffle 144 within the through hole 1411 of the insulating member 140, so that the second baffle 144 can block and buffer the electrolyte during the electrolyte filling of the single cell 100, thereby further reducing the direct impact of the electrolyte on the electrode assembly 120 during electrolyte filling, thus reducing the shedding of active materials on the positive and negative electrode plates in the electrode assembly 120, reducing the safety hazards of the single cell 100, and ensuring the yield of the finished product of the single cell 100. At the same time, the second baffle 144 also partially blocks the top cover 130, further reducing the overlap area between the top cover 130 and the through hole 1411, preventing the electrode tabs of the electrode assembly 120 from extending into the through hole 1411 and contacting the top cover 130, causing a short circuit in the single cell 100, further reducing the risk of short circuit between the electrode assembly 120 and the top cover 130, and ensuring the safety performance of the single cell 100.

[0113] In one embodiment, the orthographic projection area of ​​each second baffle 144 on the reference plane O is S3 mm. 2 The following condition is satisfied: 0.0002≤S3 / S2≤0.15; that is, the orthogonal projection area of ​​each second baffle 144 on the reference plane O is S3mm. 2 The orthographic projection area S2 mm of the hole wall of through hole 1411 on reference plane O 2 The ratio can be controlled within the range of 0.0002 to 0.15. For example, S3 / S2 can be a range of one or any two of the following: 0.0002, 0.01, 0.02, 0.03, 0.04, 0.05, 0.06, 0.07, 0.08, 0.09, 0.1, 0.11, 0.12, 0.13, 0.14, or 0.15. The specific values ​​of S3 / S2 given above are merely illustrative; any value within the range of 0.0002 to 0.15 is within the scope of protection of this application.

[0114] This application defines the orthographic projection area S3 mm of each of the second flow-blocking portions 144 on the reference plane O. 2 The orthographic projection area S2 mm of the hole wall of through hole 1411 on reference plane O 2The ratio is in the range of 0.0002 to 0.15, so that the structural dimensions between the second baffle 144 and the through hole 1411 are reasonably designed. This allows the second baffle 144 to block and buffer the electrolyte during the electrolyte filling of the single cell 100, thereby reducing the direct impact of the electrolyte on the electrode assembly 120 during the electrolyte filling process. This reduces the shedding of active materials from the positive and negative electrode plates in the electrode assembly 120, reduces the safety hazards of the single cell 100, and ensures the yield of the finished product of the single cell 100. At the same time, the second baffle 144 also partially blocks the top cover 130, further reducing the overlap area between the top cover 130 and the through hole 1411. This prevents the electrode tabs of the electrode assembly 120 from extending into the through hole 1411 and contacting the top cover 130, which could cause a short circuit in the single cell 100. This further reduces the risk of a short circuit between the electrode assembly 120 and the top cover 130, ensuring the safety performance of the single cell 100.

[0115] Among them, the orthographic projection area of ​​each second flow-blocking part 144 on the reference plane O is S3 mm. 2 The actual single cell 100 can be disassembled, and the image area of ​​any one of the second current-blocking portions 144 of the insulating component 140 can be measured multiple times using a projection measurement device (such as a digital microscope or image measuring instrument) to obtain the orthographic projection area S3 mm of each second current-blocking portion 144 on the reference plane O. 2 However, it is not limited to this.

[0116] In one embodiment, the orthographic projection area of ​​each second baffle 144 on the reference plane O is S3 mm. 2 The condition is satisfied that 0.021 ≤ S3 / S2 ≤ 0.097. That is, the orthogonal projection area S3mm² of each of the second baffle sections 144 on the reference plane O. 2 The orthographic projection area S2 mm of the hole wall of through hole 1411 on reference plane O 2 The ratio can be controlled within the range of 0.021 to 0.058. For example, S3 / S2 can be a range consisting of one or any two of the following: 0.021, 0.025, 0.03, 0.035, 0.04, 0.045, 0.05, 0.055, 0.06, 0.065, 0.07, 0.075, 0.08, 0.095, 0.09, 0.095, or 0.097. The specific values ​​of S3 / S2 given above are merely illustrative; any value within the range of 0.021 to 0.097 is within the scope of protection of this application.

[0117] This application defines the orthographic projection area S3 mm of each of the second flow-blocking portions 144 on the reference plane O. 2 The orthographic projection area S2 mm of the hole wall of through hole 1411 on reference plane O 2The ratio is in the range of 0.021 to 0.097, so as to further optimize the structural dimensions between the second baffle 144 and the through hole 1411. This allows the second baffle 144 to block and buffer the electrolyte during the electrolyte filling of the single cell 100, thereby reducing the direct impact of the electrolyte on the electrode assembly 120 during the electrolyte filling process. This reduces the shedding of active materials from the positive and negative electrode plates in the electrode assembly 120, reduces the safety hazards of the single cell 100, and ensures the yield of the finished product of the single cell 100. At the same time, the second baffle 144 also partially blocks the top cover 130, further reducing the overlap area between the top cover 130 and the through hole 1411. This prevents the electrode tabs of the electrode assembly 120 from extending into the through hole 1411 and contacting the top cover 130, thus avoiding a short circuit in the single cell 100. This further reduces the risk of short circuit between the electrode assembly 120 and the top cover 130, ensuring the safety performance of the single cell 100.

[0118] For example, in this application, the orthographic projection of each second flow-blocking portion 144 on the reference plane O is fan-shaped, and the central angle of each second flow-blocking portion 144 is 35°.

[0119] In one embodiment, the orthographic projection area of ​​each second baffle 144 on the reference plane O is S3 mm. 2 It also satisfies: 0.046≤S3≤38.151. That is, the orthogonal projection area S3 mm of each of the second flow-blocking parts 144 on the reference plane O. 2 It can be controlled within 0.046mm 2 ~38.151mm 2 Within the range. For example, S3 mm 2 It can be 0.046mm 2 4mm 2 8mm 2 10mm 2 12mm 2 16mm 2 20mm 2 24mm 2 28mm 2 30mm 2 32mm 2 36mm 2 38mm 2 Or 38.151mm 2 The range consisting of one or any two of them. S3 mm 2 The specific values ​​mentioned above are merely illustrative examples; as long as it is within 0.046mm... 2 ~38.151mm 2Any value within the range is within the protection scope of this application. This application defines the orthographic projection area S3 mm of each second flow-blocking part 144 on the reference plane O. 2 At 0.046mm 2 ~38.151mm 2 Within the specified range, the second baffle 144 is used to block and buffer the electrolyte during the electrolyte filling of the single cell 100, thereby reducing the direct impact of the electrolyte on the electrode assembly 120 during electrolyte filling. This reduces the shedding of active materials from the positive and negative electrode plates in the electrode assembly 120, reduces safety hazards of the single cell 100, and ensures the yield of the finished product of the single cell 100. It also further reduces the overlap area between the top cover 130 and the through hole 1411, preventing the electrode tabs of the electrode assembly 120 from extending into the through hole 1411 and contacting the top cover 130, thus preventing a short circuit in the single cell 100. This further reduces the risk of short circuit between the electrode assembly 120 and the top cover 130 and ensures the safety performance of the single cell 100.

[0120] In one embodiment, the orthographic projection area of ​​each second baffle 144 on the reference plane O is S3 mm. 2 It can be controlled within 0.148mm 2 ~24.67mm 2 Within the range.

[0121] In one embodiment, in the radial direction P, the second baffle 144 extends along the hole wall 1412 toward the center of the through hole 1411; exemplaryly, in this application, in the radial direction P, the second baffle 144 extends along the hole wall 1412 toward the center of the through hole 1411.

[0122] Specifically, the second flow-blocking portion 144 has a radial dimension of L2 mm on P, satisfying: 0.017 ≤ L2 / D ≤ 0.47. That is, the ratio of the radial dimension L2 mm of the second flow-blocking portion 144 to the maximum outline dimension D mm of the through hole 1411 can be controlled within the range of 0.017 to 0.47. For example, L2 / D can be one or a combination of any two of the following: 0.017, 0.05, 0.1, 0.15, 0.2, 0.25, 0.3, 0.35, 0.4, or 0.47. The specific values ​​of L2 / D given above are merely illustrative; any value within the range of 0.017 to 0.47 is within the scope of protection of this application.

[0123] The dimension L2 mm of the second baffle 144 in the radial direction P can be obtained by disassembling the actual single cell 100 and measuring the distance between the outer wall of the second baffle 144 near the center of the through hole 1411 and the hole wall 1412 on the insulating member 140 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.

[0124] Understandably, this application defines the second baffle portion 144 in the radial direction (L2 mm) and the maximum profile dimension D of the through hole 1411 by limiting the second baffle portion 144 in the radial direction (L2 mm). The ratio of mm is in the range of 0.017 to 0.47, so that the structural dimensions between the second baffle 144 and the through hole 1411 are reasonably designed to ensure that the electrolyte flows efficiently through the through hole 1411 when the single cell 100 is filled with electrolyte, that is, to ensure the filling efficiency of the single cell 100. At the same time, it ensures that the second baffle 144 can effectively block and buffer the electrolyte, reducing the direct impact of the electrolyte on the electrode assembly 120 during the filling of the single cell 100, thereby reducing the shedding of active materials on the positive and negative electrode plates in the electrode assembly 120 and reducing the safety hazards of the single cell 100. It also ensures that the second baffle 144 can effectively block the overlapping area of ​​the top cover 130 and the through hole 1411, preventing the electrode tab of the electrode assembly 120 from extending into the through hole 1411 and contacting the top cover 130, causing a short circuit in the single cell 100, reducing the short circuit risk between the electrode assembly 120 and the top cover 130, and ensuring the safety performance of the single cell 100.

[0125] Furthermore, the radial dimension L2 mm of the second flow-blocking portion 144 in the radial direction P also satisfies: 0.06 ≤ L2 / D ≤ 0.18. That is, the ratio of the radial dimension L2 mm of the second flow-blocking portion 144 in the radial direction P to the maximum outline dimension D mm of the through hole 1411 can be controlled within the range of 0.06 to 0.18. For example, L2 / D can be one or any combination of two of the following: 0.06, 0.07, 0.08, 0.09, 0.1, 0.11, 0.12, 0.13, 0.14, 0.15, 0.16, 0.17, or 0.18. The specific values ​​of L2 / D given above are merely illustrative, and any value within the range of 0.06 to 0.18 is within the protection scope of this application. This application limits the ratio of the radial dimension L2 mm of the second flow-blocking portion 144 to the maximum outline dimension D mm of the through hole 1411 to within the range of 0.06 to 0.18, thereby further optimizing the structural dimensions between the second flow-blocking portion 144 and the through hole 1411. This ensures better liquid injection efficiency of the single cell 100 while also ensuring that the second flow-blocking portion 144 can effectively block the overlapping area of ​​the top cover 130 and the through hole 1411. This prevents the electrode tabs of the electrode assembly 120 from extending into the through hole 1411 and contacting the top cover 130, thus reducing the risk of short circuit between the electrode assembly 120 and the top cover 130 and ensuring the safety performance of the single cell 100.

[0126] In one embodiment, reference is made to Figures 6 to 7The second flow-blocking portion 144, with a radial dimension L2 mm, also satisfies the condition: 0.051 ≤ L2 ≤ 8.46. That is, the radial dimension L2 mm of the second flow-blocking portion 144 can be controlled within the range of 0.051 mm to 8.46 mm. For example, L2 mm can be any one of 0.051 mm, 1 mm, 2 mm, 3 mm, 4 mm, 4 mm, 6 mm, 7 mm, 8 mm, or 8.46 mm, or any combination thereof. The specific values ​​of L2 mm given above are merely illustrative; any value within the range of 0.051 mm to 8.46 mm is within the scope of protection of this application. This application limits the radial dimension L2 mm of the second flow-blocking portion 144 to within the range of 0.051 mm to 8.46 mm to rationally design the structural dimensions of the second flow-blocking portion 144. This further ensures that the second flow-blocking portion 144 can effectively block and buffer the electrolyte, reducing the direct impact of the electrolyte on the electrode assembly 120 during electrolyte injection of the single cell 100. This reduces the shedding of active materials from the positive and negative electrode plates in the electrode assembly 120, thereby reducing the safety hazards of the single cell 100. It also ensures that the second flow-blocking portion 144 can effectively shield the overlapping area of ​​the top cover 130 and the through hole 1411, preventing the electrode tabs of the electrode assembly 120 from extending into the through hole 1411 and contacting the top cover 130, thus causing a short circuit in the single cell 100. This reduces the risk of short circuit between the electrode assembly 120 and the top cover 130, ensuring the safety performance of the single cell 100.

[0127] Furthermore, the radial dimension L2 mm of the second flow-blocking portion 144 in the radial direction P also satisfies: 0.36 ≤ L2 ≤ 2.16. That is, the radial dimension L2 mm of the second flow-blocking portion 144 in the radial direction P can be controlled within the range of 0.36 mm to 2.16 mm. For example, L2 mm can be one or any combination of two of the following: 0.36 mm, 0.4 mm, 0.6 mm, 0.8 mm, 1 mm, 1.2 mm, 1.4 mm, 1.6 mm, 1.8 mm, 1.2 mm, or 2.16 mm. The specific values ​​of L2 mm given above are merely illustrative examples, and any value within the range of 0.36 mm to 2.16 mm is within the protection scope of this application. This application limits the radial dimension L2mm of the second flow-blocking portion 144 to within the range of 0.36mm to 2.16mm to further optimize the structural dimensions of the second flow-blocking portion 144. This ensures that the second flow-blocking portion 144 can effectively block and buffer the electrolyte, reducing the direct impact of the electrolyte on the electrode assembly 120 during electrolyte injection of the single cell 100. This reduces the shedding of active materials from the positive and negative electrode plates in the electrode assembly 120, thereby reducing the safety hazards of the single cell 100. It also ensures that the second flow-blocking portion 144 can effectively shield the overlapping area of ​​the top cover 130 and the through hole 1411, preventing the electrode tabs of the electrode assembly 120 from extending into the through hole 1411 and contacting the top cover 130, thus preventing a short circuit in the single cell 100. This reduces the risk of a short circuit between the electrode assembly 120 and the top cover 130, ensuring the safety performance of the single cell 100.

[0128] In one embodiment, the plurality of second flow-blocking portions 144 may be arranged asymmetrically.

[0129] In another embodiment, reference is made to Figures 6 to 7 Multiple second flow-blocking sections 144 are symmetrically arranged about the central axis Q to ensure that the electrolyte can flow quickly from the through hole 1411 into the receiving cavity 111 when the single cell 100 is filled with electrolyte. This ensures the safety performance of the single cell 100 while improving the electrolyte filling efficiency of the single cell 100. At the same time, it facilitates the processing and forming of the insulating component 140 and improves the production efficiency of the single cell 100.

[0130] In one embodiment, reference is made to Figures 3 to 5 The insulating member 140 also includes a pressure relief boss 145, which protrudes from the insulating body 141 on the side near the electrode assembly 120, and the pressure relief boss 145 and the through hole 1411 are spaced apart in the second direction X.

[0131] The insulating body 141 and the pressure relief boss 145 can be integrally formed, meaning they form a single structure. Alternatively, the insulating body 141 and the pressure relief boss 145 can be separately configured and fixedly connected to each other. For example, the pressure relief boss 145 is fixedly connected to the insulating body 141 using a snap-fit ​​process. This application does not impose specific limitations and can be configured according to actual circumstances. For example, in this application, the insulating body 141 and the pressure relief boss 145 are integrally injection molded.

[0132] The single cell 100 also includes a pressure relief valve 160, which is disposed on the top cover 130. Along the first direction Z, the orthographic projection of the pressure relief valve 160 on the reference plane at least partially coincides with the orthographic projection of the pressure relief boss 145 on the reference plane, so as to ensure that the gas generated during thermal runaway of the single cell 100 is discharged efficiently.

[0133] Specifically, to ensure the safety performance of the single battery cell 100, in this application, the distance between the pressure relief boss 145 and the through hole 1411 is T2 mm, and the dimension of the insulating body 141 in the second direction X is T1 mm, satisfying: 0.005 ≤ T2 / T1 ≤ 0.833. That is, the ratio of the distance T2 mm between the pressure relief boss 145 and the through hole 1411 and the dimension T1 mm of the insulating body 141 in the second direction X can be controlled within the range of 0.005 to 0.833. For example, T2 / T1 can be one of 0.005, 0.05, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, or 0.833, or any combination thereof. The specific values ​​of T2 / T1 given above are only illustrative examples, and any value within the range of 0.005 to 0.833 is within the protection scope of this application.

[0134] This application limits the ratio of the distance T2 mm between the pressure relief boss 145 and the through hole 1411 to the dimension T1 mm of the insulating body 141 in the second direction X to be within the range of 0.005 to 0.833. This allows for a more reasonable design of the structural dimensions of the insulating member 140, preventing the distance between the pressure relief boss 145 and the through hole 1411 from being too close. This would prevent the electrolyte from impacting the pressure relief valve 160 during electrolyte injection, causing the pressure relief valve 160 to loosen and affecting its normal operation. This ensures the safety performance of the single cell 100 and also guarantees the yield of the finished single cell 100.

[0135] The distance T2 mm between the pressure relief boss 145 and the through hole 1411 can be obtained by disassembling the actual single battery cell 100 and measuring the distance between the outer wall of the pressure relief boss 145 near the through hole 1411 and the hole wall of the through hole 1411 near the pressure relief boss 145 multiple times using a measuring tool, and then 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.

[0136] The dimension T1 mm of the insulating body 141 in the second direction X can be obtained by disassembling the actual single cell 100 and measuring the distance between the two relatively positioned outer walls of the insulating body 141 in the second direction X multiple times using a measuring tool, and then 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.

[0137] In one embodiment, in order to ensure the safety performance of the single cell 100, reference is made in this application. Figure 5 The distance T2 mm between the pressure relief boss 145 and the through hole 1411 also satisfies: 3 ≤ T2 ≤ 500. That is, the distance T2 mm between the pressure relief boss 145 and the through hole 1411 can be controlled within the range of 3 mm to 500 mm. For example, T2 mm can be one or any combination of 3 mm, 50 mm, 100 mm, 150 mm, 200 mm, 250 mm, 300 mm, 350 mm, 400 mm, 450 mm, or 500 mm. The specific values ​​of T2 mm mentioned above are only given as examples, and any value within the range of 3 mm to 500 mm is within the protection scope of this application.

[0138] This application limits the distance T2 mm between the pressure relief boss 145 and the through hole 1411 to within the range of 3 mm to 500 mm, so as to further rationally design the structural dimensions of the insulating component 140. This further avoids the pressure relief boss 145 and the through hole 1411 being too close, which could cause the pressure relief valve 160 to loosen due to the impact of the electrolyte on the pressure relief valve 160 during the filling of the single cell 100, thus affecting the normal use of the pressure relief valve 160. This further ensures the safety performance of the single cell 100 and guarantees the yield of the finished single cell 100.

[0139] In one embodiment, reference is made to Figure 5The dimension T1 mm of the insulating body 141 in the second direction X also satisfies: 10 ≤ T1 ≤ 600. That is, the dimension T1 mm of the insulating body 141 in the second direction X can be controlled within the range of 10 mm to 600 mm. For example, T1 mm can be one or any combination of two of the following: 10 mm, 50 mm, 100 mm, 150 mm, 200 mm, 250 mm, 300 mm, 350 mm, 400 mm, 450 mm, 500 mm, 550 mm, or 600 mm. The specific values ​​of T1 mm given above are only illustrative examples, and any value within the range of 10 mm to 600 mm is within the protection scope of this application.

[0140] In one embodiment, reference is made to Figures 3 to 5 The single cell also includes: a terminal post 150, which is disposed on the top cover 130, and a portion of the terminal post 150 passes through the insulating body 141. The terminal post 150 is electrically connected to the electrode assembly 120, and the through hole 1411 is located between the terminal post 150 and the pressure relief boss 145.

[0141] The terminal 150 can be either a positive terminal or a negative terminal. This application does not make specific limitations and can be set according to the actual situation.

[0142] Specifically, in order to ensure the structural stability of the single cell 100, this application refers to... Figure 5 The distance between the pole post 150 and the through hole 1411 is T3 mm, satisfying: 0.0067 ≤ T3 / T1 ≤ 0.833. That is, the ratio of the distance T3 mm between the pole post 150 and the through hole 1411 to the dimension T1 mm of the insulating body 141 in the second direction X can be controlled within the range of 0.0067 to 0.833. For example, T3 / T1 can be one of 0.0067, 0.05, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, or 0.833, or any combination thereof. The specific values ​​of T3 / T1 given above are merely illustrative; any value within the range of 0.0067 to 0.833 is within the protection scope of this application. This application limits the ratio of the distance T3 mm between the terminal post 150 and the through hole 1411 to the dimension T1 mm of the insulating body 141 in the second direction X to be within the range of 0.0067 to 0.833, so as to further rationally design the structural dimensions of the insulating member 140, ensure the overall flatness of the insulating member 140, and thus ensure the tight assembly between the insulating member 140 and the top cover 130, and ensure the structural stability between the components of the single cell 100.

[0143] The distance T3 mm between the terminal post 150 and the through hole 1411 can be obtained by disassembling the actual single cell 100 and measuring the distance between the outer wall of the terminal post 150 near the through hole 1411 and the hole wall of the through hole 1411 near the terminal post 150 multiple times using a measuring tool, and then 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.

[0144] In one embodiment, reference is made to Figure 5 The distance T3 mm between the pole post 150 and the through hole 1411 also satisfies: 4 ≤ T3 ≤ 500. That is, the distance T3 mm between the pole post 150 and the through hole 1411 can be controlled within the range of 4 mm to 500 mm. For example, T3 mm can be one or any combination of 4 mm, 50 mm, 100 mm, 150 mm, 200 mm, 250 mm, 300 mm, 350 mm, 400 mm, 450 mm, or 500 mm. The specific values ​​of T3 mm given above are only illustrative examples, and any value within the range of 4 mm to 500 mm is within the protection scope of this application. This application limits the distance T3 mm between the terminal post 150 and the through hole 1411 to within the range of 4 mm to 500 mm, so as to further rationally design the structural dimensions of the insulating member 140, further ensure the overall flatness of the insulating member 140, further ensure the tight assembly between the insulating member 140 and the top cover 130, and ensure the structural stability between the components of the single cell 100.

[0145] In another embodiment, reference is made to Figure 10 This application also provides a battery pack, including: a housing 200, a single battery 100 as in any of the above embodiments, and a cover 300; the single battery 100 is disposed inside the housing 200, and the cover 300 is disposed on one side of the housing 200 in the first direction Z to seal the housing 200.

[0146] The battery pack can be a three-tiered system consisting of individual battery cells 100, battery modules, and a battery pack. This means that the individual battery cells 100 are first grouped into battery modules, and then the battery modules are placed inside the housing 200 to form a battery pack. Alternatively, it can be a two-tiered system consisting of individual battery cells 100 and a battery pack, where the individual battery cells 100 are directly housed inside the housing 200 to form a 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.

[0147] On the other hand, in embodiments of this application, an electrical device is also provided, including a battery pack as described above, which serves as the power supply for the electrical device. The electrical device may be, but is not limited to, mobile devices (e.g., mobile phones, laptops, etc.), electric vehicles (e.g., pure electric vehicles, hybrid electric vehicles, plug-in hybrid electric vehicles, electric bicycles, electric scooters, electric golf carts, electric trucks, etc.), electric trains, ships and satellites, energy storage systems, etc.

[0148] To better understand the technical solution of this application, the following explanation uses a lithium-ion battery as an example.

[0149] This example provides a method for preparing a lithium-ion battery, the specific process of which is as follows:

[0150] 1. Preparation of positive electrode sheet

[0151] Lithium iron phosphate, conductive carbon black (SP), and polyvinylidene fluoride (PVDF) were mixed in a mass ratio of 96:2:2. N-methylpyrrolidone (NMP) was then added as a solvent and mixed. The mixture was stirred under vacuum until it became homogeneous, thus obtaining a positive electrode slurry. The positive electrode slurry was then uniformly coated on both sides of a positive electrode current collector aluminum foil and then transferred to a 120°C oven for drying. After rolling, slitting, and cutting, the positive electrode sheet was obtained.

[0152] 2. Preparation of negative electrode sheet

[0153] The negative electrode active material graphite, conductive agent conductive carbon black (SP), thickener sodium carboxymethyl cellulose (CMC), and binder styrene-butadiene rubber (SBR) were mixed in a mass ratio of 96.2:1.2:1.2:1.4. Then, deionized water was added as a solvent for mixing. The mixture was stirred under vacuum until the system became homogeneous, thus obtaining the negative electrode slurry. The negative electrode slurry was uniformly coated on both sides of the negative electrode current collector copper foil, and then transferred to a 110°C oven for drying. After that, the negative electrode sheets were obtained by rolling, slitting, and cutting.

[0154] 3. Preparation of electrolyte

[0155] Ethylene carbonate (EC), ethyl methyl carbonate (EMC), and diethyl carbonate (DEC) were mixed in a mass ratio of 3:4:3 to obtain an organic solvent. 1 mQl / L of LiPF6 was added and mixed thoroughly. Then, vinylene carbonate, ethylene sulfate, and lithium difluorophosphate were added to prepare the electrolyte.

[0156] 4. Preparation of the diaphragm

[0157] PP film is used as the separator.

[0158] 5. Preparation of lithium-ion batteries

[0159] After drying, the negative and positive electrode sheets prepared by the above steps are used together with the separator to prepare a wound electrode assembly using a winding machine. The positive and negative electrode tabs are welded to the top cover, and the welded electrode assembly with the top cover is placed into an aluminum shell for encapsulation. After filling with electrolyte and forming and fixing the volume, a lithium-ion battery is obtained.

[0160] The lithium-ion batteries in each example and comparative example were prepared according to the above-described preparation method. The structural dimensions and performance test data of each example and comparative example are shown in Tables 1, 2 and 3.

[0161] The battery packs prepared using the above examples and comparative models were subjected to performance testing. The specific testing methods are as follows:

[0162] 1. Test method for electrolyte filling efficiency of lithium-ion batteries

[0163] Using the insulating component described in this application, the lithium-ion battery is placed in a liquid injection machine. The machine first evacuates the lithium-ion battery to a pressure below -90 kPa, at which point the electrolyte is stored in the injection cup. Due to the negative pressure inside the lithium-ion battery, the electrolyte flows into the battery. The machine then cycles the lithium-ion battery through alternating positive and negative pressure cycles (positive pressure 180 kPa (30-60 s), negative pressure -60 kPa (3-15 s), 4-12 times) to ensure sufficient electrolyte injection. The total injection time is recorded as T. Alternatively, using a conventional insulating component (i.e., without any structure at the through-hole of the insulating component), the same injection operation is performed, and the total injection time is recorded as t. The injection efficiency is calculated as t / T × 100%.

[0164] 2. Test methods for the voltage of lithium-ion batteries

[0165] At 25°C, the positive and negative terminals of a lithium-ion battery are electrically connected to a short-circuit voltmeter, and the voltage value of the lithium-ion battery is measured using the short-circuit voltmeter.

[0166] 3. Test method for the detonation pressure of lithium-ion battery pressure relief valve

[0167] Insert the connecting tube with the external pressure gauge into the injection hole and seal the injection hole. Use the connecting tube to fill the lithium-ion battery with helium and record the pressure displayed on the pressure gauge when the pressure relief valve detonates.

[0168] 4. Test method for the flatness of insulating components in lithium-ion batteries

[0169] After the prepared lithium-ion battery is left to stand for a period of time, it is disassembled. The disassembled insulating component is placed on a platform, and the base of the height gauge is placed on the platform. The sliding rod of the height gauge is adjusted so that it contacts the surface between the through hole and the terminal of the insulating component. The height gauge is moved and the readings of multiple points are recorded. The flatness of the surface of the insulating component is calculated by calculating the difference between the maximum and minimum readings.

[0170] Table 1 shows the radial dimension L1 mm of the first baffle 143 in the radial direction P, the radial dimension L2 mm of the second baffle 144 in the radial direction P, the maximum outline dimension D mm of the through hole 1411, and the orthographic projection area S1 mm of each first baffle 143 on the reference plane O. 2 The projected area of ​​each second baffle 144 on the reference plane O is S3 mm. 2 The orthographic projection area S2 mm of the hole wall of through hole 1411 on reference plane O 2 The impact of the parameter relationship between them on lithium-ion batteries.

[0171] Table 1. Parameters and test results for Examples 1-31 and Comparative Examples 1-4

[0172]

[0173]

[0174]

[0175] As shown in Table 1, in Comparative Example 2, the specific parameters of the lithium-ion battery exceed the range specified in this application. Compared to the lithium-ion batteries in Examples 1 to 16, the electrolyte injection efficiency of the lithium-ion battery in Comparative Example 2 is significantly reduced, the electrolyte injection effect is poor, and the lithium-ion battery does not exhibit the corresponding performance, thus failing to meet the requirements. In Comparative Examples 1 and 3, the specific parameters of the lithium-ion batteries exceed the range specified in this application. Compared to the lithium-ion batteries in Examples 1 to 16, although the electrolyte injection efficiency of the lithium-ion batteries in Comparative Examples 1 and 3 is higher, the voltage value of the lithium-ion batteries in Comparative Examples 1 and 3 decreases, the lithium-ion batteries experience short circuits, and the lithium-ion batteries do not exhibit the corresponding performance, thus failing to meet the requirements. The requirements are not met. However, in Comparative Example 5, the specific parameters of the lithium-ion battery exceed the parameter range in this application. Compared with the lithium-ion batteries in Examples 17 to 32, the liquid injection efficiency of the lithium-ion battery in Comparative Example 5 is significantly reduced, the liquid injection effect is poor, and the lithium-ion battery does not exhibit the corresponding performance, thus failing to meet the requirements. In Comparative Examples 4 and 6, the specific parameters of the lithium-ion battery exceed the parameter range in this application. Compared with the lithium-ion batteries in Examples 17 to 32, although the liquid injection efficiency of the lithium-ion batteries in Comparative Examples 4 and 6 is higher, the voltage value of the lithium-ion batteries in Comparative Examples 4 and 6 decreases, the lithium-ion batteries experience short circuits, and the lithium-ion batteries do not exhibit the corresponding performance, thus failing to meet the requirements.

[0176] Therefore, this application limits the orthographic projection area S1 mm of each first flow-blocking part 143 on the reference plane O. 2 The orthographic projection area S2 mm of the hole wall of through hole 1411 on reference plane O 2 The ratio is in the range of 0.0002 to 0.28, limiting the orthographic projection area S1 mm of each first baffle 143 on the reference plane O. 2 At 0.051mm 2 ~71.2472mm 2 Within the specified range, the orthographic projection area S2 mm of the hole wall of the through hole 1411 onto the reference plane O 2 At 7.065mm 2 ~254.34mm 2 Within the specified range, the projected area S3 mm of each of the second flow-blocking sections 144 on the reference plane O is defined. 2 The orthographic projection area S2 mm of the hole wall of through hole 1411 on reference plane O 2 The ratio is in the range of 0.0002 to 0.15, and the orthographic projection area S3 mm of each second baffle 144 on the reference plane O is limited. 2 At 0.046mm 2 ~38.151mm 2Within the specified range, the ratio of the radial dimension L1 mm of the first flow-blocking portion 143 to the maximum outline dimension D mm of the through hole 1411 is limited to the range of 0.01 to 1.67; the ratio of the radial dimension L2 mm of the second flow-blocking portion 144 to the maximum outline dimension D mm of the through hole 1411 is limited to the range of 0.017 to 0.47; the radial dimension L1 mm of the first flow-blocking portion 143 is limited to the range of 0.03 mm to 8.46 mm; the maximum outline dimension D mm of the through hole 1411 is limited to the range of 3 mm to 18 mm; and the radial dimension L2 mm of the second flow-blocking portion 144 is limited to the range of 0.01 to 1.67. The diameter of the electrode assembly 100 is within the range of 0.03mm to 8.46mm to ensure the electrolyte filling efficiency of the single cell 100. At the same time, the first baffle 143 can effectively block and buffer the electrolyte, reducing the direct impact of the electrolyte on the electrode assembly 120 during electrolyte filling, thereby reducing the shedding of active materials on the positive and negative electrode plates in the electrode assembly 120 and reducing the safety hazards of the single cell 100. At the same time, the first baffle 143 can effectively block the overlapping area of ​​the top cover 130 and the through hole 1411, preventing the electrode tab of the electrode assembly 120 from extending into the through hole 1411 and contacting the top cover 130, causing a short circuit in the single cell 100, reducing the risk of short circuit between the electrode assembly 120 and the top cover 130, and ensuring the safety performance of the single cell 100.

[0177] Table 2 shows the effect of the parameter relationship between the distance T2 mm between the pressure relief boss 145 and the through hole 1411 and the dimension T1 mm of the insulating body 141 in the second direction X on the lithium-ion battery.

[0178] Table 2 Parameters and Test Results for Examples 33-46

[0179] Example 33 3 600 0.005 0.9 Example 34 200 600 0.333 0.94 Example 35 500 600 0.833 0.98 Example 36 3 10 0.3 0.88 Example 37 3.5 60 0.058 0.89 Example 38 4 120 0.033 0.96 Example 39 12.5 148 0.084 0.94 Example 40 22.5 160 0.141 0.97 Example 41 35 173 0.202 0.89 Example 42 100 194 0.515 0.87 Example 43 150 200 0.75 0.85 Example 44 45 280 0.161 0.92 Example 45 9.8 300 0.033 0.91 Example 46 0.5 600 0.0008 0.5

[0180] As can be seen from the data in Table 2, in Example 46, the specific parameters of the lithium-ion battery exceed the parameter range in this application. Compared with the lithium-ion batteries in Examples 33 to 45, the detonation pressure of the pressure relief valve of the lithium-ion battery in Example 46 is significantly reduced, the safety performance of the lithium-ion battery is poor, and the lithium-ion battery does not exhibit the corresponding performance and does not meet the requirements.

[0181] Therefore, this application limits the ratio of the distance T2 mm between the pressure relief boss 145 and the through hole 1411 to the dimension T1 mm of the insulating body 141 in the second direction X to be within the range of 0.005 to 0.833, and limits the distance T2 mm between the pressure relief boss 145 and the through hole 1411 to be within the range of 3 mm to 500 mm, so as to reasonably design the structural dimensions of the insulating member 140. This avoids the distance between the pressure relief boss 145 and the through hole 1411 being too close, which would cause the pressure relief valve 160 to loosen due to the impact of the electrolyte on the pressure relief valve 160 when the single cell 100 is filled with electrolyte, thus affecting the normal use of the pressure relief valve 160 and ensuring the safety performance of the single cell 100.

[0182] Table 3 shows the effect of the parameter relationship between the distance T3 mm between the terminal post 150 and the through hole 1411 and the dimension T1 mm of the insulating body 141 in the second direction X on the lithium-ion battery.

[0183] Table 3 Parameters and test results for Examples 47-62

[0184] Example 47 4 600 0.0067 0.3 Example 48 200 600 0.333 0.19 Example 49 500 600 0.833 0.1 Example 50 4 10 0.4 0.29 Example 51 8 60 0.1333 0.22 Example 52 13 120 0.1083 0.12 Example 53 24 148 0.1622 0.15 Example 54 50 160 0.3125 0.09 Example 55 100 173 0.578 0.2 Example 56 150 194 0.7732 0.17 Example 57 33 200 0.165 0.19 Example 58 43 220 0.1955 0.13 Example 59 45 280 0.1607 0.16 Example 60 13 300 0.0433 0.18 Example 61 300 400 0.75 0.21 Example 62 1 600 0.0017 0.4

[0185] As can be seen from the data in Table 3, in Example 62, the specific parameters of the lithium-ion battery exceed the parameter range in this application. Compared with the lithium-ion batteries in Examples 47 to 61, the flatness of the insulating member 140 in the lithium-ion battery in Example 62 is significantly increased, and the planar deformation of the insulating member 140 is large. The lithium-ion battery does not exhibit the corresponding performance and does not meet the requirements.

[0186] Therefore, this application limits the ratio of the distance T3 mm between the electrode post 150 and the through hole 1411 to the dimension T1 mm of the insulating body 141 in the second direction X to be within the range of 0.0067 to 0.833, and limits the distance T3 mm between the electrode post 150 and the through hole 1411 to be within the range of 4 mm to 500 mm, so as to reasonably design the structural dimensions of the insulating member 140, ensure the overall flatness of the insulating member 140, and thus ensure the tight assembly between the insulating member 140 and the top cover 130, and ensure the structural stability between the components of the single cell 100.

[0187] 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 a first direction and a reference plane perpendicular to the first direction, characterized in that, include: The housing has a receiving cavity; The electrode assembly is disposed within the receiving cavity; A top cover is connected to one side of the housing in the first direction and seals the receiving cavity, and the top cover is provided with a liquid injection hole; as well as An insulating component includes: an insulating body, a plurality of flow guiding portions, and a plurality of first flow blocking portions. The insulating body is connected to the top cover near the electrode assembly. The insulating body has a through hole that communicates with the injection hole. The plurality of flow guiding portions are all connected to the insulating body near the electrode assembly and surround the outer periphery of the through hole to form an open flow guiding channel that communicates with the through hole. The open portion connects the flow guiding channel to the receiving cavity. Two adjacent flow guiding portions are spaced apart to form a first flow guiding port between them, which connects the flow guiding channel to the receiving cavity. Each first flow blocking portion is connected to one of the flow guiding portions near the electrode assembly. Two adjacent first flow blocking portions are spaced apart, and the first flow blocking portion blocks at least part of the open portion. Wherein, the orthographic projection area of ​​each of the first flow-blocking parts on the reference plane is S1 mm², and the orthographic projection area of ​​the hole wall of the through hole on the reference plane is S2 mm², satisfying: 0.0002≤S1 / S2≤0.28; The through hole has a hole wall; The insulating component further includes: a plurality of second flow-blocking portions, each of which is connected to the hole wall and disposed within the through hole, with each second flow-blocking portion disposed between two adjacent flow-guiding portions.

2. The single-cell battery as described in claim 1, characterized in that, The orthographic projection area S1 mm² of each of the first flow-blocking parts on the reference plane and the orthographic projection area S2 mm² of the hole wall of the through hole on the reference plane also satisfy: 0.04≤S1 / S2≤0.

2.

3. The single-cell battery as described in claim 2, characterized in that, The projected area S1 mm² of each of the first flow-blocking portions on the reference plane also satisfies: 0.051 ≤ S1 ≤ 71.245; and / or, The orthographic projection area S2 mm² of the hole wall on the reference plane also satisfies: 7.065≤S2≤254.

34.

4. The single-cell battery as described in claim 2, characterized in that, The through hole has a radial direction perpendicular to the first direction; The first baffle has a radial dimension of L1 mm, and the maximum profile dimension of the through hole is D mm, satisfying: 0.01 ≤ L1 / D ≤ 0.47; or, The first flow-blocking part has a radial dimension L1 mm and the maximum profile dimension D mm of the through hole, which also satisfy: 0.06≤L1 / D≤0.

18.

5. The single-cell battery as described in claim 4, characterized in that, The radial dimension L1mm of the first baffle also satisfies: 0.03≤L1≤8.46; and / or, The maximum outline dimension D mm of the through hole also satisfies: 3≤D≤18.

6. The single-cell battery as described in claim 1, characterized in that, The through hole has a central axis that extends along the first direction, and the radius of the through hole intersects the central axis. The plurality of flow guides are arranged symmetrically about the central axis, and the plurality of first flow deflectors are arranged symmetrically about the central axis.

7. The single-cell battery as described in claim 6, characterized in that, The flow guide extends along the first direction; or... The flow guide is inclined relative to the first direction, and in the first direction, along the direction of the insulating member toward the electrode assembly, the distance between the flow guide and the central axis of the through hole decreases.

8. The single-cell battery as described in claim 1, characterized in that, The projected area of ​​each of the second flow-blocking portions on the reference plane is S3 mm², satisfying: 0.0002 ≤ S3 / S2 ≤ 0.15; or, The orthographic projection area of ​​each of the second flow-blocking parts on the reference plane is S3 mm², which satisfies: 0.021≤S3 / S2≤0.

097.

9. The single-cell battery as described in claim 8, characterized in that, The projected area S3 mm² of each of the second flow-blocking parts on the reference plane also satisfies: 0.046≤S3≤38.

151.

10. The single-cell battery as described in claim 8, characterized in that, The through hole has a radial direction perpendicular to the first direction; In the radial direction, the second baffle extends along the hole wall toward the center of the through hole; The second baffle has a radial dimension of L2 mm, satisfying: 0.017 ≤ L2 / D ≤ 0.47; or; The second flow-blocking part has a radial dimension L2 mm that also satisfies: 0.06≤L2 / D≤0.

18.

11. The single-cell battery as described in claim 10, characterized in that, The radial dimension L2 mm of the second baffle also satisfies: 0.051 ≤ L2 ≤ 8.46; or, The second baffle portion has a radial dimension L2 mm that also satisfies: 0.36≤L2≤2.

16.

12. The single-cell battery as described in claim 1, characterized in that, The single cell also has a second direction intersecting the first direction; The insulating component further includes: a pressure relief boss, which protrudes from the insulating body on the side near the electrode assembly, and the pressure relief boss and the through hole are spaced apart in the second direction; The distance between the pressure relief boss and the through hole is T2 mm, and the dimension of the insulating body in the second direction is T1 mm, satisfying: 0.005≤T2 / T1≤0.

833.

13. The single-cell battery as described in claim 12, characterized in that, The distance T2 mm between the pressure relief boss and the through hole also satisfies: 3 ≤ T2 ≤ 500; and / or, The dimension T1 mm of the insulating body in the second direction also satisfies: 10≤T1≤600.

14. The single-cell battery as described in claim 12, characterized in that, The single battery also includes: an electrode post disposed on the top cover, and a portion of the electrode post passing through the insulating body and electrically connected to the electrode assembly; the through hole is located between the electrode post and the pressure relief boss. The distance between the pole and the through hole is T3 mm, which satisfies: 0.0067≤T3 / T1≤0.

833.

15. The single-cell battery as described in claim 14, characterized in that, The distance T3 mm between the pole post and the through hole also satisfies: 4≤T3≤500.

16. A battery pack, characterized in that, include: Box; as well as The single-cell battery as described in any one of claims 1 to 15, wherein the single-cell battery is disposed within the housing.

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