Single battery and battery pack

Abstract

The embodiment of the invention relates to the technical field of batteries, and particularly discloses a single battery and a battery pack, and the single battery comprises a shell provided with an accommodating cavity; the electrode assembly is arranged in the accommodating cavity; the top cover is connected to one side, in the first direction, of the shell and covers and seals the containing cavity, and a liquid injection hole is formed in the top cover; the insulating component comprises an insulating main body, a plurality of flow guide parts and a plurality of first flow blocking parts, the insulating main body is provided with a through hole, and the through hole is communicated with the liquid injection hole; the multiple flow guide parts surround the 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 flow guide channel is communicated with the containing cavity through the opening; the first flow blocking part blocks part of the opening. According to the invention, the tab of the electrode assembly is prevented from extending into the through hole and being in contact with the top cover to cause short circuit of the single battery, the risk of short circuit between the electrode assembly and the top cover is reduced, and the safety performance of the single battery is ensured.

Description

Technical Field

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

[0002] With the rapid development of the new energy industry, secondary batteries with high energy density, high cycle life and high safety performance have been widely used and developed, and the demand for secondary batteries with larger capacity, longer durability and greater safety is urgent. Safety performance is one of the core performances of secondary batteries. Therefore, how to improve the safety performance of secondary batteries has become an urgent problem to be solved. Summary of the invention

[0003] The embodiments of the present application provide a single cell battery and a battery pack to improve the safety performance of the single cell battery.

[0004] In order to solve the above technical problems, the embodiments of the present application disclose the following technical solutions:

[0005] In one aspect, a single cell is provided, having a first direction and a reference plane perpendicular to the first direction, comprising: a housing provided with a receiving cavity;

[0006] An electrode assembly is disposed in the accommodating cavity;

[0007] A top cover connected to one side of the shell in the first direction and covering the accommodating cavity, and a liquid injection hole is opened on the top cover; and

[0008] The insulating component comprises: an insulating body, a plurality of flow guides and a plurality of first flow blocking parts, the insulating body being connected to a side of the top cover close to the electrode assembly, the insulating body being provided with a through hole, the through hole being connected to the injection hole; the plurality of flow guides are all connected to a side of the insulating body close to the electrode assembly, and the plurality of flow guides are arranged around the periphery of the through hole to form a flow guide channel with an open opening, the flow guide channel is connected to the through hole, and the open opening connects the flow guide channel with the accommodating cavity; two adjacent flow guides are arranged at intervals to form a first flow guide opening between the two adjacent flow guides, the first flow guide opening connects the flow guide channel with the accommodating cavity; each first flow blocking part is respectively connected to a side of a flow guide part close to the electrode assembly, the two adjacent first flow blocking parts are arranged at intervals, and the first flow blocking part blocks at least part of the open opening;

[0009] The orthographic projection area of ​​each first baffle on the reference plane is S1 mm 2 The orthographic projection area of ​​the through hole wall on the reference plane is S2 mm 2 , satisfying: 0.0002≤S1 / S2≤0.28.

[0010] In addition to one or more of the features disclosed above, or as an alternative, the orthographic projection area S1 mm of each first baffle on the reference plane2 And the orthographic projection area of ​​the through 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 as an alternative, the orthographic projection area S1 mm of each first baffle on the reference plane 2 Also satisfying: 0.051≤S1≤71.245; and / or,

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

[0013] In addition to or as an alternative to one or more of the features disclosed above, the through hole has a radial direction perpendicular to the first direction; the radial dimension of the first baffle is L1 mm, the maximum profile dimension of the through hole is D mm, and the following conditions are satisfied: 0.01≤L1 / D≤0.47; or,

[0014] The radial dimension L1 mm of the first flow blocking portion and the maximum outline dimension D mm of the through hole also satisfy the following: 0.06≤L1 / D≤0.18.

[0015] In addition to one or more of the features disclosed above, or as an alternative, the radial dimension L1 mm of the first baffle portion further 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 as an alternative, the radial dimension L1 mm of the first baffle portion further 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 or as an alternative to one or more features disclosed above, the through hole has a central axis, the central axis extends along the first direction, and the radius of the through hole intersects the central axis;

[0020] The plurality of flow guides are centrally symmetrically arranged about the central axis, and the plurality of first flow blocking portions are centrally symmetrically arranged about the central axis.

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

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

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

[0024] The insulating component further comprises: a plurality of second flow blocking parts, each of which is connected to the hole wall and arranged in the through hole, and each of which is arranged between two adjacent flow guiding parts.

[0025] In addition to one or more of the features disclosed above, or as an alternative, the orthographic projection area of ​​each second baffle on the reference plane is S3 mm 2 , satisfying: 0.0002≤S3 / S2≤0.15; or,

[0026] The orthographic projection area of ​​each second baffle on the reference plane is S3 mm 2 , satisfying: 0.021≤S3 / S2≤0.097.

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

[0028] In addition to or as an alternative to one or more of the features disclosed above, in a radial direction, the second flow blocking portion extends 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 flow blocking portion also satisfies: 0.06≤L2 / D≤0.18.

[0031] In addition to one or more of the features disclosed above, or as an alternative, the radial dimension L2 mm of the second baffle portion further satisfies: 0.051≤L2≤8.46; or,

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

[0033] In addition to or as an alternative to one or more of the features disclosed above, the single battery further has a second direction intersecting the first direction;

[0034] The insulating member further includes: a pressure relief boss, which is convexly arranged on a side of the insulating body close to the electrode assembly, and the pressure relief boss is spaced apart from the through hole 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 as an alternative, the distance T2 mm between the pressure relief boss and the through hole further satisfies: 3≤T2≤500; and / or,

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

[0038] In addition to or as an alternative to one or more of the features disclosed above, the single cell further comprises: a pole, which is disposed on the top cover, and a portion of the pole is passed through the insulating body and is electrically connected to the electrode assembly, and the through hole is located between the pole and the pressure relief boss;

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

[0040] In addition to or as an alternative to one or more of the features disclosed above, the distance T3 mm between the pole and the through hole further satisfies: 4≤T3≤500.

[0041] On the other hand, a battery pack is further disclosed. In addition to or as an alternative to one or more of the features disclosed above, the battery pack includes a case; and a single cell as described in any of the above items, wherein the single cell is disposed in the case.

[0042] One of the above technical solutions has the following advantages or beneficial effects: the present application sets a first baffle on the side of the guide portion close to the electrode assembly to use the first baffle to block part of the opening, and at the same time limits the ratio of the dimension L1 mm of the first baffle in the radial direction P to the maximum outline dimension Dmm of the through hole within the range of 0.01 to 1.67 to ensure the injection efficiency of the single cell; at the same time, ensure that the first baffle can effectively block and buffer the electrolyte, reduce the direct impact of the electrolyte on the electrode assembly during injection of the single cell, thereby reducing the shedding of active materials on the positive and negative electrode sheets in the electrode assembly, and reducing the safety hazards of the single cell; at the same time, ensure that the first baffle can effectively block the overlapping area between the top cover and the through hole, avoid the electrode ear of the electrode assembly extending into the through hole and contacting the top cover to cause a short circuit in the single cell, reduce the risk of short circuit between the electrode assembly and the top cover, and ensure the safety performance of the single cell. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] The technical solution and other beneficial effects of the present application will be made apparent by describing in detail the specific implementation methods of the present application in conjunction with the accompanying drawings.

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

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

[0046] Figure 3 is an exploded structural view of a top cover and an insulating member provided according to an embodiment of the present application;

[0047] Figure 4 is an exploded structural view of a top cover and an insulating member from another perspective according to an embodiment of the present application;

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

[0049] Figure 6 is a bottom view of an insulating component provided according to an embodiment of the present application;

[0050] Figure 7 yes Figure 6 A partial enlarged view of point B in the middle;

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

[0052] Fig. 9 yes Figure 8 A partial enlarged view of point C in the middle;

[0053] Fig.10 It is a schematic diagram of the structure of a battery pack provided according to an embodiment of the present application.

[0054] Description of reference numerals:

[0055] 100. Single cell;

[0056] 110. housing; 111. accommodating chamber;

[0057] 120. Electrode assembly;

[0058] 130, top cover; 131, liquid injection hole;

[0059] 140, insulating member; 141, insulating body; 1411, through hole; 1412, hole wall; 142, flow guide; 1421, flow guide channel; 1422, open mouth; 1423, first flow guide port; 143, first flow blocking portion; 144, second flow blocking portion; 145, pressure relief boss;

[0060] 150, pole;

[0061] 160. Pressure relief valve;

[0062] 200, box body;

[0063] 300. Box cover. DETAILED DESCRIPTION

[0064] In order to make the purpose, technical solution and beneficial effects of this application more clear, the following further describes this application in detail in conjunction with the accompanying drawings and specific implementation methods. It should be understood that the specific implementation methods described in this specification are only for explaining this application, not for limiting this application.

[0065] In the description of the present application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, which are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application. In addition, the terms "first" and "second" are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present application, the meaning of "multiple" refers to two or more, unless otherwise clearly and specifically defined.

[0066] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0067] In the present application, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0068] The existing secondary battery injection process usually uses injection equipment to directly inject electrolyte into the interior of the secondary battery through the injection hole and the lower plastic through hole. However, in actual production, in order to improve process efficiency and ensure that the electrolyte fills the battery cell, a higher injection pressure is usually used for injection. However, due to the high injection pressure, there is no diversion barrier when the electrolyte is injected. The electrolyte flow flowing in from the injection hole and the lower plastic through hole will directly impact the positive and negative electrodes and diaphragm inside the secondary battery, damage the internal structure of the battery, and affect the finished product yield and safety performance of the battery.

[0069] In order to solve the above problems, in the embodiments of the present application, refer to Figures 1 to 9 The present application provides a single cell 100, wherein the single cell 100 has a first direction Z, a second direction X, and a third direction Y intersecting each other. Exemplarily, the single cell 100 has a first direction Z, a second direction X, and a third direction Y perpendicular to each other. 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 battery 100 includes a housing 110 , an electrode assembly 120 , a top cover 130 and an insulating member 140 .

[0071] Specifically, the shell 110 is provided with a accommodating cavity 111; the electrode assembly 120 is arranged in the accommodating cavity 111; the top cover 130 is connected to one side of the shell 110 in the first direction Z, the top cover 130 covers the accommodating cavity 111, and a liquid injection hole 131 is opened on the top cover 130; the insulating component 140 is arranged in the accommodating cavity 111, and the insulating component 140 is connected to a side of the top cover 130 close to the electrode assembly 120.

[0072] The single cell 100 may be a secondary battery, which refers to a single cell that can be used continuously by activating active materials by charging after the single cell is discharged. Exemplarily, the single cell 100 may be a lithium ion battery, a sodium ion battery, a sodium lithium ion battery, a lithium metal battery, a sodium metal battery, a lithium sulfur battery, a magnesium ion battery, a nickel metal hydride battery or a nickel cadmium battery, but is not limited thereto.

[0073] The single battery 100 may be a prismatic battery, a soft pack battery or a battery of other shapes. For example, in the present application, the single battery 100 is a square battery.

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

[0075] The top cover 130 can be integrally formed with the shell 110, that is, the top cover 130 can be the outer wall of the shell 110; the top cover 130 can also be fixedly connected to the shell 110, for example, the top cover 130 is fixedly connected to one end of the shell 110 in the axial direction Z by welding or other processes. This is not specifically limited in this application and can be specifically set according to actual circumstances. For example, in this application, the top cover 130 and the shell 110 are separately set, and the top cover 130 and the shell 110 are welded and fixed.

[0076] The insulating component 140 may be made of rubber, silicone or plastic, but is not limited thereto.

[0077] Among them, the single cell 100 also includes an electrolyte, a pole 150 and other functional components. The electrolyte can be a conventional electrolyte or a special electrolyte with additives added. The electrolyte is used to soak the electrode assembly 120. Among them, the electrode assembly 120 is a component in the single cell 100 where an electrochemical reaction occurs, and the electrode assembly can be one or more. The electrode assembly 120 is mainly formed by winding or stacking a positive electrode sheet, a diaphragm and a negative electrode sheet. The parts of the positive electrode sheet and the negative electrode sheet with active substances constitute the main body of the electrode assembly 120, and the parts of the positive electrode sheet and the negative electrode sheet without active substances constitute the pole ears. During the charge and discharge process of the single cell 100, the positive electrode active substance and the negative electrode active substance react with the electrolyte, and the pole ears are electrically connected to the pole 150 to form a current loop, so that the single cell 100 can be used normally.

[0078] Specifically, the insulating member 140 includes: an insulating body 141, a plurality of guide portions 142 and a plurality of first baffle portions 143. The insulating body 141 is connected to a side of the top cover 130 close to the electrode assembly 120. The insulating body 141 is provided with a through hole 1411, and the through hole 1411 is connected to the injection hole 131. The plurality of guide portions 142 are all connected to a side of the insulating body 141 close to the electrode assembly 120, and the plurality of guide portions 142 are arranged around the outer periphery of the through hole 1411 to form a guide channel 1421 with an opening 1422. The guide channel 1421 is connected to the through hole 1411, and the opening 1422 connects the guide channel 1421 with the accommodating chamber 111; two adjacent guide parts 142 are arranged at intervals to form a first guide opening 1423 between the two adjacent guide parts 142, and the first guide opening 1423 connects the guide channel 1421 with the accommodating chamber 111; each first baffle part 143 is respectively connected to a side of a guide part 142 close to the electrode assembly 120, and two adjacent first baffle parts 143 are arranged at intervals and the first baffle part 143 blocks at least part of the opening 1422.

[0079] The insulating body 141 and the guide part 142 can be integrally formed, that is, the insulating body 141 and the guide part 142 are an integral structure; the insulating body 141 and the guide part 142 can also be separately provided, and fixedly connected to each other, and illustratively, the guide part 142 is fixedly connected to the insulating body 141 by a process such as snap-on. This is not specifically limited in this application, and can be specifically set according to actual circumstances. For example, in this application, the insulating body 141 and the guide part 142 are integrally injection molded.

[0080] The first baffle 143 and the guide 142 can be integrally formed, that is, the first baffle 143 and the guide 142 are an integral structure; the first baffle 143 and the guide 142 can also be separately provided, and fixedly connected to each other, and illustratively, the first baffle 143 is fixedly connected to the guide 142 by a process such as a snap connection. This is not specifically limited in this application, and can be specifically set according to actual circumstances. For example, in this application, the first baffle 143 and the guide 142 are integrally injection molded.

[0081] In which, the single cell battery also has a reference plane (not shown in the figure) perpendicular to the first direction Z. Along the first direction Z, the orthographic projection of the first baffle portion 143 on the reference plane at least partially overlaps with the orthographic projection of the inner wall of the opening 1422 on the reference plane, that is, at least part of the first baffle portion 143 is located in the opening 1422.

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

[0083] It can be understood that when the single battery 100 is injected, the electrolyte flows from the injection hole 131 to the through hole 1411, and then flows from the through hole 1411 to the guide channel 1421. Part of the electrolyte in the guide channel 1421 flows from the open port 1422 to the accommodating cavity 111, and another part of the electrolyte in the guide channel 1421 flows from the first guide port 1423 to the accommodating cavity 111. By guiding the electrolyte, the electrolyte of the single battery 100 is further reduced from directly impacting the electrode assembly 120 during injection, thereby reducing the shedding of active materials on the positive and negative electrode sheets in the electrode assembly 120, and reducing the safety hazards of the single battery 100. At the same time, the present application provides a method for A first baffle 143 is provided on a side close to the electrode assembly 120, so as to utilize the first baffle 143 to block a portion of the opening 1422, so as to reduce the direct impact of the electrolyte of the single cell 100 on the electrode assembly 120 during the injection of the electrolyte, thereby reducing the shedding of active materials on the positive and negative electrode sheets in the electrode assembly 120, and reducing the potential safety hazards of the single cell 100; at the same time, it is ensured that the first baffle 143 can effectively block the overlapping area between the top cover 130 and the through hole 1411, so as to prevent the pole ear of the electrode assembly 120 from extending into the through hole 1411 and contacting the top cover 130 to cause a short circuit in the single cell 100, thereby 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.

[0084] Specifically, the single battery 100 further has a reference plane O perpendicular to the first direction Z. Exemplarily, in the present application, the reference plane O may 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 baffle 143 on the reference plane O is S1 mm 2 The orthographic projection area of ​​the through hole 1411 on the reference plane O is S2 mm 2 , satisfying: 0.0002≤S1 / S2≤0.28. That is, the orthographic projection area of ​​each first baffle 143 on the reference plane O is S1 mm 2 and the orthographic projection area S2 mm of the hole wall of through hole 1411 on reference plane O 2 The ratio of S1 / S2 can be controlled within the range of 0.0002 to 0.28. For example, S1 / S2 can be 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, or any two of them. The above specific values ​​of S1 / S2 are only given by way of example, and any value within the range of 0.0002 to 0.28 is within the protection scope of the present application.

[0086] In this application, the orthographic projection area S1 mm of each first baffle 143 on the reference plane O is defined as 2 and the orthographic projection area S2 mm of the hole wall of through hole 1411 on reference plane O 2 The ratio is within the range of 0.0002 to 0.28, so as to reasonably design the structural dimensions between the first baffle 143 and the through hole 1411 to ensure the injection efficiency of the single cell 100; at the same time, it is ensured that the first baffle 143 can effectively block and buffer the electrolyte, reduce the direct impact of the electrolyte of the single cell 100 on the electrode assembly 120 during injection, thereby reducing the shedding of active materials on the positive and negative electrode sheets in the electrode assembly 120, and reducing the safety hazards of the single cell 100; at the same time, it is ensured that the first baffle 143 can effectively block the overlapping area of ​​the top cover 130 and the through hole 1411, avoid the ear of the electrode assembly 120 from extending into the through hole 1411 and contacting the top cover 130 to cause a short circuit in the single cell 100, reduce the short circuit risk between the electrode assembly 120 and the top cover 130, and ensure the safety performance of the single cell 100.

[0087] The orthographic projection area S1 mm of each first baffle 143 on the reference plane O is 2 After the actual single battery 100 is disassembled, the image area of ​​any one of the first current blocking portions 143 of the insulating member 140 can be measured multiple times using a projection measurement device (such as a digital microscope or an image measuring instrument) to obtain the orthographic projection area S1 mm of each first current blocking portion 143 on the reference plane O. 2 , but not limited to this.

[0088] The orthographic projection area of ​​the hole wall of the through hole 1411 on the reference plane O is S2 mm 2 After disassembling the actual single battery 100, the image area of ​​the hole wall of the through hole 1411 of the insulating member 140 can be measured multiple times using a projection measurement device (such as a digital microscope or an image measuring instrument) to obtain the orthographic projection area S2 mm of the hole wall of the through hole 1411 on the reference plane O. 2 , but not limited to this.

[0089] The hole wall of the through hole 1411 only encloses the inner wall of the through hole 1411 and does not include the outer wall surface of other structures. In one embodiment, the orthographic projection area S1 mm of each first baffle 143 on the reference plane O is 2 and 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 orthographic projection area of ​​each first baffle 143 on the reference plane O is S1 mm 2 and the orthographic projection area S2 mm of the hole wall of through hole 1411 on reference plane O2 The ratio of S1 / S2 can be controlled within the range of 0.04 to 0.2. For example, S1 / S2 can be 0.04, 0.06, 0.08, 0.1, 0.12, 0.14, 0.16, 0.18 or 0.2, or any two of them. The above specific values ​​of S1 / S2 are given for example only, and any value within the range of 0.04 to 0.2 is within the protection scope of the present application.

[0090] In this application, the orthographic projection area S1 mm of each first baffle 143 on the reference plane O is defined as 2 and 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, so as to further reasonably design the structural dimensions between the first baffle 143 and the through hole 1411 to ensure the injection efficiency of the single cell 100; at the same time, it is further ensured that the first baffle 143 can effectively block and buffer the electrolyte, reduce the direct impact of the electrolyte of the single cell 100 on the electrode assembly 120 during injection, thereby reducing the shedding of active materials on the positive and negative electrode sheets in the electrode assembly 120, and reducing the safety hazards of the single cell 100; at the same time, it is ensured that the first baffle 143 can effectively block the overlapping area of ​​the top cover 130 and the through hole 1411, avoid the ear of the electrode assembly 120 from extending into the through hole 1411 and contacting the top cover 130 to cause a short circuit in the single cell 100, reduce the short circuit risk between the electrode assembly 120 and the top cover 130, and ensure the safety performance of the single cell 100.

[0091] Exemplarily, in the present 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 S1 mm of each first baffle 143 on the reference plane O is 2 It also satisfies: 0.051≤S1≤71.245. That is, the orthographic projection area S1 mm of each first baffle 143 on the reference plane O is 2 Can be controlled within 0.051mm 2 ~71.245mm 2 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 above specific values ​​of S1 are given for example only. 2 ~71.245mm 2 Any value within the range is within the protection scope of this application. This application defines the positive projection area S1 mm of each first baffle 143 on the reference plane O. 2 At 0.051mm 2 ~71.245mm 2 range to ensure the injection efficiency of the single cell 100; at the same time, further ensure that the first baffle 143 can effectively block and buffer the electrolyte, reduce the direct impact of the electrolyte on the electrode assembly 120 during the injection of the single cell 100, thereby reducing the shedding of active materials on the positive and negative electrodes in the electrode assembly 120, and reducing the safety hazards of the single cell 100; at the same time, ensure that the first baffle 143 can effectively block the overlapping area of ​​the top cover 130 and the through hole 1411, avoid the electrode ear of the electrode assembly 120 from extending into the through hole 1411 and contacting the top cover 130 to cause a short circuit in the single cell 100, reduce the short circuit risk between the electrode assembly 120 and the top cover 130, and ensure the safety performance of the single cell 100.

[0093] The orthographic projection area of ​​the hole wall of the 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 of ​​the hole wall of the through hole 1411 on the reference plane O is S2 mm 2 Can be controlled at 7.065mm 2 ~254.34mm 2 Range. Exemplary, S2 mm 2 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 2, 250mm 2 or 254.34mm 2 The range consisting of one or any two of them. S2 mm 2 The above specific values ​​are given for example only. 2 ~13.176mm 2 Any value within the range is within the protection scope of the present application. The present application defines the orthographic projection area S2 mm of the hole wall of the through hole 1411 on the reference plane O. 2 At 7.065mm 2 ~254.34mm 2 Within the range, the structural dimensions of the through hole 1411 are reasonably designed to further ensure that the electrolyte efficiently flows through the through hole 1411 when the single cell 100 is injected, thereby ensuring the injection efficiency of the single cell 100.

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

[0095] In one embodiment, in order to ensure the injection efficiency of the single cell 100 and the safety performance of the single cell 100, in this application, reference is made to Figure 6 to Figure 7 , the through hole 1411 has a radial direction P perpendicular to the first direction Z; the dimension of the first baffle 143 in the radial direction P is L1 mm, 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 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. Exemplarily, 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 a range consisting of any two of them. The above specific values ​​of L1 / D are given for example only, and any value within the range of 0.01 to 0.47 is within the protection scope of the present application.

[0096] The dimension L1 mm of the first current blocking portion 143 in the radial direction P can be obtained by disassembling the actual single battery 100, measuring the length of the first current blocking portion 143 on the insulating member 140 along the radial direction P multiple times using a measuring tool, and calculating the average value. The measuring tool can be any one of a ruler, a vernier caliper, or other dimension measuring instruments, but is not limited thereto.

[0097] The maximum outline size D mm of the through hole 1411 can be obtained by disassembling the actual single battery 100, measuring the diameters of the through holes 1411 on the insulating member 140 multiple times with a measuring tool, and calculating the average value. The measuring tool can be any one of a ruler, a vernier caliper, or other dimension measuring instruments, but is not limited thereto.

[0098] It can be understood that the present application limits the ratio of the dimension L1 mm of the first baffle 143 in the radial direction P to the maximum outline dimension D mm of the through hole 1411 within the range of 0.01 to 0.47, so as to reasonably design the structural dimensions between the first baffle 143 and the through hole 1411 to ensure the injection efficiency of the single cell 100; at the same time, it is ensured that the first baffle 143 can effectively block and buffer the electrolyte, reduce the direct impact of the electrolyte of the single cell 100 on the electrode assembly 120 during injection, thereby reducing the shedding of active materials on the positive and negative electrode sheets in the electrode assembly 120, and reducing the safety hazards of the single cell 100; at the same time, it is ensured that the first baffle 143 can effectively block the overlapping area of ​​the top cover 130 and the through hole 1411, avoid the ear of the electrode assembly 120 from extending into the through hole 1411 and contacting the top cover 130 to cause a short circuit in the single cell 100, reduce the risk of short circuit between the electrode assembly 120 and the top cover 130, and ensure the safety performance of the single cell 100.

[0099] Furthermore, the dimension L1 mm of the first baffle 143 in the radial direction P 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 dimension L1 mm of the first baffle 143 in the radial direction P and the maximum outline dimension D mm of the through hole 1411 can be controlled within the range of 0.06 to 0.18. Exemplarily, L1 / D can be a range consisting of one of 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 or any two of them. The above specific values ​​of L1 / D are given for example only, and any value within the range of 0.06 to 0.18 is within the protection scope of the present application. The present application limits the ratio of the dimension L1 mm of the first baffle 143 in the radial direction P to the maximum contour dimension D mm of the through hole 1411 within the range of 0.06 to 0.18, so as to further reasonably design the structural dimensions between the first baffle 143 and the through hole 1411, so as to better ensure the injection efficiency of the single cell 100, while ensuring that the first baffle 143 can effectively block the overlapping area between the top cover 130 and the through hole 1411, avoid the electrode ear of the electrode assembly 120 from extending into the through hole 1411 and contacting the top cover 130 to cause a short circuit in the single cell 100, reduce the risk of short circuit between the electrode assembly 120 and the top cover 130, and ensure the safety performance of the single cell 100.

[0100] In one embodiment, in order to ensure the safety performance of the single battery 100, in this application, reference is made to Figure 6 to Figure 7 , the dimension L1 mm of the first baffle 143 in the radial direction P also satisfies: 0.03≤L1≤8.46. That is, the dimension L1 mm of the first baffle 143 in the radial direction P can be controlled within the range of 0.03mm to 8.46mm. Exemplarily, L1 mm can be a range consisting of one of 0.03mm, 1mm, 2mm, 3mm, 4mm, 5mm, 6mm, 7mm, 8mm or 8.46mm or any two thereof. The above specific values ​​of L1 mm are given for example only, and any value within the range of 0.03mm to 8.46mm is within the protection scope of this application. The present application limits the dimension L1 mm of the first baffle 143 in the radial direction P to be within the range of 0.03 mm to 8.46 mm, so as to further reasonably design the structural dimensions of the first baffle 143, so as to further ensure that the first baffle 143 can effectively block and buffer the electrolyte, reduce the direct impact of the electrolyte on the electrode assembly 120 during the injection of the single cell 100, thereby reducing the shedding of active materials on the positive and negative electrode sheets in the electrode assembly 120, and reducing the safety hazards of the single cell 100; ensure that the first baffle 143 can effectively block the overlapping area of ​​the top cover 130 and the through hole 1411, avoid the electrode ear of the electrode assembly 120 from extending into the through hole 1411 and contacting the top cover 130 to cause a short circuit in the single cell 100, reduce the risk of short circuit between the electrode assembly 120 and the top cover 130, and ensure the safety performance of the single cell 100.

[0101] Furthermore, the dimension L1 mm of the first baffle 143 in the radial direction P also satisfies: 0.36≤L1≤2.16. That is, the dimension L1 mm of the first baffle 143 in the radial direction P can be controlled within the range of 0.36mm to 2.16mm. Exemplarily, L1 mm can be one of 0.36mm, 0.4mm, 0.6mm, 0.8mm, 1mm, 1.2mm, 1.4mm, 1.6mm, 1.8mm, 1.2mm or 2.16mm or a range consisting of any two of them. The above specific values ​​of L1 mm are given for example only, and any value within the range of 0.36mm to 2.16mm is within the protection scope of the present application. The present application limits the dimension L1mm of the first baffle 143 in the radial direction P to be within the range of 0.36mm to 2.16mm, so as to further reasonably design the structural dimensions of the first baffle 143, so as to further ensure that the first baffle 143 can effectively block and buffer the electrolyte, reduce the direct impact of the electrolyte on the electrode assembly 120 during the injection of the single cell 100, thereby reducing the shedding of active materials on the positive and negative electrode sheets in the electrode assembly 120, and reducing the safety hazards of the single cell 100; ensure that the first baffle 143 can effectively block the overlapping area of ​​the top cover 130 and the through hole 1411, avoid the electrode ear of the electrode assembly 120 from extending into the through hole 1411 and contacting the top cover 130 to cause a short circuit in the single cell 100, reduce the risk of short circuit between the electrode assembly 120 and the top cover 130, and ensure the safety performance of the single cell 100.

[0102] In one embodiment, in order to ensure the efficiency of the liquid injection of the single cell 100, in this application, reference is made to Figure 6 to Figure 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 3mm to 18mm. Exemplarily, the maximum outline dimension D mm can be 3mm, 4mm, 5mm, 6mm, 7mm, 8mm, 9mm, 10mm, 11mm, 12mm, 13mm, 14mm, 15mm, 16mm, 17mm or 18mm, or a range consisting of any two of them. The above specific values ​​of the maximum outline dimension D mm are given only as examples, and any value within the range of 3mm to 18mm is within the protection scope of the present application. The present application limits the maximum outline dimension D mm of the through hole 1411 within the range of 3mm to 18mm, so as to reasonably design the structural dimensions of the through hole 1411, so as to further ensure that the electrolyte efficiently flows from the through hole 1411 when the single cell 100 is injected, and ensure the injection 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 6mm to 12mm. Exemplarily, the maximum outline dimension D mm can be 6mm, 6.5mm, 7mm, 7.5mm, 8mm, 8.5mm, 9mm, 9.5mm, 10mm, 10.5mm, 11mm, 11.5mm or 12mm, or a range consisting of any two of them. The above specific values ​​of the maximum outline dimension D mm are given only as examples, and any value within the range of 6mm to 12mm is within the protection scope of the present application. The present application limits the maximum outline dimension D mm of the through hole 1411 to be within the range of 6 mm to 12 mm, and further reasonably designs the structural dimensions of the through hole 1411 to further ensure that the electrolyte efficiently flows through the through hole 1411 when the single cell 100 is injected, thereby ensuring the injection efficiency of the single cell 100; at the same time, it further avoids the electrode ear of the electrode assembly 120 from extending into the through hole 1411 and contacting the top cover 130 to cause a short circuit in the single cell 100, thereby reducing the risk of a 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 member (not shown) is further provided at the liquid injection hole 131 to seal the liquid injection hole 131 , thereby sealing the single cell 100 as a whole and ensuring the normal use of the single cell 100 .

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

[0106] In another embodiment, referring to Figure 6 to Figure 7 The through hole 1411 has a central axis Q, and the central axis Q extends along the first direction Z. The radius of the through hole 1411 intersects with the central axis Q. The plurality of guide portions 142 are symmetrically arranged about the central axis Q, and the plurality of first baffle portions 143 are symmetrically arranged about the central axis Q to ensure that the electrolyte can quickly flow from the guide channel 1421 to the accommodating cavity 111 when the single cell 100 is injected. This improves the injection 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, thereby improving the production efficiency of the single cell 100.

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

[0108] In another embodiment, referring to Figures 8 to 9The 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 guide portion 142 and the central axis Q of the through hole 1411 is reduced, so that the guide channel 1421 has a cone-shaped structure as a whole, thereby improving the guide effect of the guide channel 1421 enclosed by the guide portion 142, and at the same time, further preventing the pole ear of the electrode assembly 120 from extending into the through hole 1411 and contacting the top cover 130 to cause a short circuit in the single battery 100, thereby reducing the risk of a short circuit between the electrode assembly 120 and the top cover 130.

[0109] In one embodiment, in order to further ensure the safety performance of the single battery 100, in this application, reference is made to Figure 6 to Figure 7 The through hole 1411 has a hole wall 1412. The insulating component 140 further includes: a plurality of second flow blocking portions 144, each of which is connected to the hole wall 1412 and is disposed in the through hole 1411, and each of which is disposed between two adjacent flow guide portions 142.

[0110] The insulating body 141 and the second current blocking portion 144 can be integrally formed, that is, the insulating body 141 and the second current blocking portion 144 are an integral structure; the insulating body 141 and the second current blocking portion 144 can also be separately provided, and fixedly connected to each other, and illustratively, the second current blocking portion 144 is fixedly connected to the insulating body 141 by a process such as a snap connection. This is not specifically limited in this application, and can be specifically set according to actual circumstances. Exemplarily, in this application, the insulating body 141 and the second current blocking portion 144 are integrally injection molded.

[0111] Among them, the single battery 100 also has a reference plane (not shown in the figure) perpendicular to the first direction Z. Along the first direction Z, the orthographic projection of the second baffle 144 on the reference plane is located within the orthographic projection of the hole wall 1412 of the through hole 1411 on the reference plane, that is, the second baffle 144 is located in the through hole 1411.

[0112] It can be understood that the present application sets a second baffle 144 in the through hole 1411 of the insulating component 140 so that the second baffle 144 is used to block and buffer the electrolyte when the single cell 100 is injected, so as to further reduce the direct impact of the electrolyte of the single cell 100 on the electrode assembly 120 during injection, thereby reducing the shedding of active materials on the positive and negative electrodes in the electrode assembly 120, reducing the safety hazards of the single cell 100, and ensuring the finished product yield of the single cell 100; at the same time, the second baffle 144 also partially blocks the top cover 130 to further reduce the overlapping area between the top cover 130 and the through hole 1411, avoiding the electrode ear of the electrode assembly 120 from extending into the through hole 1411 and contacting the top cover 130 to cause 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 , satisfying: 0.0002≤S3 / S2≤0.15; that is, the orthographic projection area of ​​each second baffle 144 on the reference plane O is S3mm 2 and the orthographic projection area S2 mm of the hole wall of through hole 1411 on reference plane O 2 The ratio of S3 / S2 can be controlled within the range of 0.0002 to 0.15. Exemplarily, S3 / S2 can be 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, or any two of them. The above specific values ​​of S3 / S2 are given for example only, and any value within the range of 0.0002 to 0.15 is within the protection scope of the present application.

[0114] The present application defines the orthographic projection area S3 mm of each second baffle 144 on the reference plane O. 2 and 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 as to reasonably design the structural dimensions between the second baffle 144 and the through hole 1411, so that when the single cell 100 is injected, the second baffle 144 is used to block and buffer the electrolyte, so as to further reduce the direct impact of the electrolyte of the single cell 100 on the electrode assembly 120 during injection, thereby reducing the shedding of active materials on the positive and negative electrode sheets in the electrode assembly 120, reducing the safety hazards of the single cell 100, and ensuring the finished product yield of the single cell 100; at the same time, the second baffle 144 also partially blocks the top cover 130, so as to further reduce the overlapping area between the top cover 130 and the through hole 1411, and avoid the electrode ear of the electrode assembly 120 extending into the through hole 1411 and contacting with the top cover 130 to cause a short circuit in the single cell 100, further 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.

[0115] The orthographic projection area of ​​each second baffle 144 on the reference plane O is S3 mm. 2 After the actual single battery 100 is disassembled, the image area of ​​any second current blocking portion 144 of the insulating member 140 can be measured multiple times using a projection measurement device (such as a digital microscope or an image measuring instrument) to obtain the orthographic projection area S3 mm of each second current blocking portion 144 on the reference plane O. 2 , but 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 , satisfying: 0.021≤S3 / S2≤0.097. That is, the orthographic projection area of ​​each second baffle 144 on the reference plane O is S3mm 2 and the orthographic projection area S2 mm of the hole wall of through hole 1411 on reference plane O 2 The ratio of S3 / S2 can be controlled within the range of 0.021 to 0.058. Exemplarily, S3 / S2 can be 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, or any two of them. The above specific values ​​of S3 / S2 are only given by way of example, and any value within the range of 0.021 to 0.097 is within the protection scope of the present application.

[0117] The present application defines the orthographic projection area S3 mm of each second baffle 144 on the reference plane O. 2 and 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 reasonably design the structural dimensions between the second baffle 144 and the through hole 1411, so that when the single cell 100 is injected, the second baffle 144 is used to block and buffer the electrolyte, so as to further reduce the direct impact of the electrolyte of the single cell 100 on the electrode assembly 120 during injection, thereby reducing the shedding of active materials on the positive and negative electrode sheets in the electrode assembly 120, reducing the safety hazards of the single cell 100, and ensuring the finished product yield of the single cell 100; at the same time, the second baffle 144 also partially blocks the top cover 130, so as to further reduce the overlapping area between the top cover 130 and the through hole 1411, and avoid the electrode ear of the electrode assembly 120 extending into the through hole 1411 and contacting with the top cover 130 to cause a short circuit in the single cell 100, further 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.

[0118] Exemplarily, in the present 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 orthographic projection area of ​​each second baffle 144 on the reference plane O is S3 mm 2 Can be controlled within 0.046mm 2 ~38.151mm 2 Range. Exemplary, S3 mm 2 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 above specific values ​​are given for example only. 2 ~38.151mm 2Any value within the range is within the protection scope of this application. This application defines the positive projection area S3 mm of each second baffle 144 on the reference plane O. 2 At 0.046mm 2 ~38.151mm 2 Within the range, the second baffle 144 is used to block and buffer the electrolyte when the single cell 100 is injected, so as to further reduce the direct impact of the electrolyte of the single cell 100 on the electrode assembly 120 during injection, thereby reducing the shedding of active materials on the positive and negative electrodes in the electrode assembly 120, reducing the potential safety hazards of the single cell 100, and ensuring the finished product yield of the single cell 100; to further reduce the overlapping area between the top cover 130 and the through hole 1411, to avoid the ear of the electrode assembly 120 extending into the through hole 1411 and contacting the top cover 130 to cause a short circuit in the single cell 100, further reducing the risk of a short circuit between the electrode assembly 120 and the top cover 130, and ensuring 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 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 portion 144 extends along the hole wall 1412 toward the center of the through hole 1411; exemplarily, in the present application, in the radial direction P, the second baffle portion 144 extends along the hole wall 1412 toward the center of the through hole 1411.

[0122] Specifically, the dimension of the second baffle 144 in the radial direction P is L2 mm, which satisfies: 0.017≤L2 / D≤0.47. That is, the ratio of the dimension L2 mm of the second baffle 144 in the radial direction P to the maximum profile dimension D mm of the through hole 1411 can be controlled within the range of 0.017 to 0.47. Exemplarily, L2 / D can be one of 0.017, 0.05, 0.1, 0.15, 0.2, 0.25, 0.3, 0.35, 0.4 or 0.47 or a range consisting of any two of them. The above specific values ​​of L2 / D are given for example only, and any value within the range of 0.017 to 0.47 is within the protection scope of the present application.

[0123] The dimension L2 mm of the second baffle 144 in the radial direction P can be obtained by disassembling the actual single battery 100, measuring the distance between the outer wall of the second baffle 144 on the insulating member 140 near the center of the through hole 1411 and the hole wall 1412 for multiple times using a measuring tool, and calculating the average value. The measuring tool can be any one of a ruler, a vernier caliper, or other dimension measuring instruments, but is not limited thereto.

[0124] It can be understood that the present application defines the dimension L2 mm of the second baffle portion 144 in the radial direction P and the maximum profile dimension D of the through hole 1411. The ratio of mm is in the range of 0.017 to 0.47, so as to reasonably design the structural dimensions between the second baffle 144 and the through hole 1411 to ensure that the electrolyte efficiently flows from the through hole 1411 when the single cell 100 is injected, that is, to ensure the injection efficiency of the single cell 100; at the same time, it is ensured that the second baffle 144 can effectively block and buffer the electrolyte, reduce the direct impact of the electrolyte of the single cell 100 on the electrode assembly 120 during injection, thereby reducing the shedding of active materials on the positive and negative electrode sheets in the electrode assembly 120, and reducing the safety hazards of the single cell 100; it is ensured that the second baffle 144 can effectively block the overlapping area of ​​the top cover 130 and the through hole 1411, avoid the ear of the electrode assembly 120 from extending into the through hole 1411 and contacting the top cover 130 to cause a short circuit in the single cell 100, reduce the short circuit risk between the electrode assembly 120 and the top cover 130, and ensure the safety performance of the single cell 100.

[0125] Further, the dimension L2 mm of the second baffle 144 in the radial direction P also satisfies: 0.06≤L2 / D≤0.18. That is, the ratio of the dimension L2 mm of the second baffle 144 in the radial direction P to the maximum profile dimension D mm of the through hole 1411 can be controlled within the range of 0.06 to 0.18. Exemplarily, L2 / D can be 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 or a range consisting of any two of them. The above specific values ​​of L2 / D are given for example only, and any value within the range of 0.06 to 0.18 is within the protection scope of the present application. The present application limits the ratio of the dimension L2 mm of the second baffle 144 in the radial direction P to the maximum outline dimension D mm of the through hole 1411 within the range of 0.06 to 0.18, so as to further reasonably design the structural dimensions between the second baffle 144 and the through hole 1411, so as to better ensure the injection efficiency of the single cell 100, and at the same time better ensure that the second baffle 144 can effectively block the overlapping area between the top cover 130 and the through hole 1411, avoid the ear of the electrode assembly 120 from extending into the through hole 1411 and contacting the top cover 130 to cause a short circuit in the single cell 100, reduce the risk of short circuit between the electrode assembly 120 and the top cover 130, and ensure the safety performance of the single cell 100.

[0126] In one embodiment, referring to Figure 6 to Figure 7, the dimension L2 mm of the second baffle 144 in the radial direction P also satisfies: 0.051≤L2≤8.46. That is, the dimension L2 mm of the second baffle 144 in the radial direction P can be controlled within the range of 0.051mm to 8.46mm. Exemplarily, L2 mm can be one of 0.051mm, 1mm, 2mm, 3mm, 4mm, 4mm, 6mm, 7mm, 8mm or 8.46mm or a range consisting of any two of them. The above specific values ​​of L2 mm are given for example only, and any value within the range of 0.051mm to 8.46mm is within the protection scope of the present application. The present application limits the dimension L2 mm of the second baffle 144 in the radial direction P to be within the range of 0.051 mm to 8.46 mm, so as to reasonably design the structural dimensions of the second baffle 144, so as to further ensure that the second baffle 144 can effectively block and buffer the electrolyte, reduce the direct impact of the electrolyte on the electrode assembly 120 during the injection of the single cell 100, thereby reducing the shedding of active materials on the positive and negative electrode sheets in the electrode assembly 120, and reducing the safety hazards of the single cell 100; ensure that the second baffle 144 can effectively block the overlapping area of ​​the top cover 130 and the through hole 1411, avoid the ear of the electrode assembly 120 from extending into the through hole 1411 and contacting the top cover 130 to cause a short circuit in the single cell 100, reduce the risk of short circuit between the electrode assembly 120 and the top cover 130, and ensure the safety performance of the single cell 100.

[0127] Furthermore, the dimension L2 mm of the second baffle 144 in the radial direction P also satisfies: 0.36≤L2≤2.16. That is, the dimension L2 mm of the second baffle 144 in the radial direction P can be controlled within the range of 0.36 mm to 2.16 mm. Exemplarily, L2 mm can be one 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, or a range consisting of any two of them. The above specific values ​​of L2 mm are given for example only, and any value within the range of 0.36 mm to 2.16 mm is within the protection scope of the present application. The present application limits the dimension L2mm of the second baffle 144 in the radial direction P to be within the range of 0.36mm to 2.16mm, so as to further reasonably design the structural dimensions of the second baffle 144, and further ensure that the second baffle 144 can effectively block and buffer the electrolyte, reduce the direct impact of the electrolyte on the electrode assembly 120 during the injection of the single cell 100, thereby reducing the shedding of active materials on the positive and negative electrode sheets in the electrode assembly 120, and reducing the safety hazards of the single cell 100; ensure that the second baffle 144 can effectively block the overlapping area of ​​the top cover 130 and the through hole 1411, avoid the electrode ear of the electrode assembly 120 from extending into the through hole 1411 and contacting the top cover 130 to cause a short circuit in the single cell 100, reduce the risk of short circuit between the electrode assembly 120 and the top cover 130, and ensure 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, referring to Figure 6 to Figure 7 The plurality of second baffles 144 are symmetrically arranged about the central axis Q to ensure that the electrolyte can quickly flow from the through hole 1411 to the accommodating cavity 111 when the single cell 100 is injected, thereby improving the injection efficiency of the single cell 100 while ensuring the safety performance of the single cell 100; at the same time, it is convenient for the processing and forming of the insulating component 140, thereby improving the production efficiency of the single cell 100.

[0130] In one embodiment, referring to Figures 3 to 5 The insulating component 140 further includes: a pressure relief boss 145, which is protruding from a side of the insulating body 141 close to the electrode assembly 120, and the pressure relief boss 145 is spaced apart from the through hole 1411 in the second direction X.

[0131] Among them, the insulating body 141 and the pressure relief boss 145 can be integrally formed, that is, the insulating body 141 and the pressure relief boss 145 are an integral structure; the insulating body 141 and the pressure relief boss 145 can also be separately set, and the two are fixedly connected. Exemplarily, the pressure relief boss 145 is fixedly connected to the insulating body 141 by a clamping process. This is not specifically limited in this application and can be specifically set according to actual circumstances. Exemplarily, in this application, the insulating body 141 and the pressure relief boss 145 are integrally injection molded.

[0132] Among them, the single cell 100 also includes: a pressure relief valve 160, which is arranged on the top cover 130, and along the first direction Z, the orthographic projection of the pressure relief valve 160 on the reference plane and the orthographic projection of the pressure relief boss 145 on the reference plane at least partially overlap, so as to ensure that the gas generated when the single cell 100 thermally runs away is efficiently discharged.

[0133] Specifically, in order to ensure the safety performance of the single battery 100, in the present application, the distance between the pressure relief boss 145 and the through hole 1411 is T2 mm, and the size 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 size T1 mm of the insulating body 141 in the second direction X can be controlled within the range of 0.005 to 0.833. Exemplarily, T2 / T1 can be a range consisting of 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 two of them. The above specific values ​​of T2 / T1 are given only as examples, and any value within the range of 0.005 to 0.833 is within the protection scope of the present application.

[0134] The present 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, so as to further reasonably design the structural dimensions of the insulating component 140, so as to avoid the distance between the pressure relief boss 145 and the through hole 1411 being too close, so as to avoid the electrolyte impacting the pressure relief valve 160 when the single cell 100 is injected with electrolyte, causing the pressure relief valve 160 to loosen and thus affecting the normal use of the pressure relief valve 160, thereby ensuring the safety performance of the single cell 100 and the finished product yield of the 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 100, measuring the distance between the outer wall of the pressure relief boss 145 close to the through hole 1411 and the hole wall of the through hole 1411 close to the pressure relief boss 145 for multiple times, and calculating the average value. The measuring tool can be any one of a ruler, a vernier caliper, or other dimension measuring instruments, but is not limited thereto.

[0136] The dimension T1 mm of the insulating body 141 in the second direction X can be obtained by disassembling the actual single battery 100, measuring the distance between two outer walls of the insulating body 141 arranged opposite to each other in the second direction X for multiple times using a measuring tool, and calculating the average value. The measuring tool can be any one of a ruler, a vernier caliper, or other dimension measuring instruments, but is not limited thereto.

[0137] In one embodiment, in order to ensure the safety performance of the single battery 100, in this application, reference is made to 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 3mm to 500mm. Exemplarily, T2mm can be a range consisting of one of 3mm, 50mm, 100mm, 150mm, 200mm, 250mm, 300mm, 350mm, 400mm, 450mm or 500mm or any two of them. The above specific values ​​of T2 mm are given only as examples, and any value within the range of 3mm to 500mm is within the protection scope of this application.

[0138] The present application 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 further reasonably design the structural dimensions of the insulating component 140, so as to further avoid the distance between the pressure relief boss 145 and the through hole 1411 being too close, so that when the single cell 100 is injected with electrolyte, the electrolyte impacts the pressure relief valve 160, causing the pressure relief valve 160 to loosen, thereby affecting the normal use of the pressure relief valve 160, further ensuring the safety performance of the single cell 100, and at the same time ensuring the finished product yield of the single cell 100.

[0139] In one embodiment, referring to Figure 5, the 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 10mm to 600mm. Exemplarily, T1 mm can be one of 10mm, 50mm, 100mm, 150mm, 200mm, 250mm, 300mm, 350mm, 400mm, 450mm, 500mm, 550mm or 600mm, or a range consisting of any two of them. The above specific values ​​of T1 mm are given only as examples, and any value within the range of 10mm to 600mm is within the protection scope of this application.

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

[0141] Among them, the pole 150 can be a positive pole or a negative pole, which is not specifically limited in the present application and can be specifically set according to actual circumstances.

[0142] Specifically, in order to ensure the structural stability of the single battery 100, in this application, reference is made to Figure 5 , the distance between the pole 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 150 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 0.0067 to 0.833. Exemplarily, T3 / T1 can be a range consisting of 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 two of them. The above specific values ​​of T3 / T1 are given only as examples, and any value within the range of 0.0067 to 0.833 is within the protection scope of this application. The present application limits the ratio of the distance T3 mm between the pole 150 and the through hole 1411 to the dimension T1 mm of the insulating body 141 in the second direction X within the range of 0.0067 to 0.833, so as to further reasonably design the structural dimensions of the insulating member 140 to ensure the overall flatness of the insulating member 140, thereby ensuring the tight assembly between the insulating member 140 and the top cover 130, and ensuring the structural stability between the various components of the single battery 100.

[0143] The distance T3 mm between the pole 150 and the through hole 1411 can be obtained by disassembling the actual single battery 100, measuring the distance between the outer wall of the pole 150 near the through hole 1411 and the hole wall of the through hole 1411 near the pole 150 for multiple times, and calculating the average value. The measuring tool can be any one of a ruler, a vernier caliper, or other dimension measuring instruments, but is not limited thereto.

[0144] In one embodiment, referring to Figure 5 , the distance T3 mm between the pole 150 and the through hole 1411 also satisfies: 4≤T3≤500. That is, the distance T3 mm between the pole 150 and the through hole 1411 can be controlled within the range of 4mm to 500mm. Exemplarily, T3mm can be one of 4mm, 50mm, 100mm, 150mm, 200mm, 250mm, 300mm, 350mm, 400mm, 450mm or 500mm, or a range consisting of any two of them. The above specific values ​​of T3 mm are only given by way of example, and any value within the range of 4mm to 500mm is within the protection scope of this application. The present application limits the distance T3 mm between the pole 150 and the through hole 1411 to be within the range of 4 mm to 500 mm, so as to further reasonably design the structural dimensions of the insulating component 140, further ensure the overall flatness of the insulating component 140, further ensure the tight assembly between the insulating component 140 and the top cover 130, and ensure the structural stability between the various components of the single battery 100.

[0145] In another embodiment, referring to Fig.10 The present application also provides a battery pack, comprising: a box body 200, a single cell 100 as in any of the above embodiments, and a box cover 300; the single cell 100 is arranged in the box body 200, and the box cover 300 is arranged on one side of the box body 200 in the first direction Z to seal the box body 200.

[0146] The battery pack may be a battery pack with three layers of single battery 100-battery module-battery pack, that is, the single battery 100 is first grouped into a battery module, and then the battery module is placed in the box 200 to form a battery pack; or a battery pack with two layers of single battery 100-battery pack, that is, the single battery 100 is directly placed in the box 200 to form a battery pack. This application does not make specific restrictions, and can be specifically set according to actual circumstances, as long as it does not affect the effect of this application.

[0147] On the other hand, in an embodiment of the present application, the present application further provides an electric device, including a battery pack as described above, the battery pack serving as a power supply for the electric device. The electric device may be, but is not limited to, a mobile device (such as a mobile phone, a laptop computer, etc.), an electric vehicle (such as a pure electric vehicle, a hybrid electric vehicle, a plug-in hybrid electric vehicle, an electric bicycle, an electric scooter, an electric golf cart, an electric truck, etc.), an electric train, a ship, a satellite, an energy storage system, etc.

[0148] In order to better understand the technical solution of the present application, a lithium-ion battery is taken as an example for further explanation below.

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

[0150] 1. Preparation of positive electrode

[0151] The positive electrode active material is lithium iron phosphate, the conductive agent is conductive carbon black (SP), and the binder is polyvinylidene fluoride (PVDF) in a mass ratio of 96:2:2, and then N-methylpyrrolidone (NMP) is added as a solvent for mixing, and stirred under vacuum until the system becomes uniform to obtain a positive electrode slurry; the positive electrode slurry is evenly coated on both sides of the positive electrode current collector aluminum foil, and then transferred to a 120°C oven for drying, and then rolled, slit, and cut into pieces to obtain a positive electrode sheet.

[0152] 2. Preparation of negative electrode sheet

[0153] The negative electrode active material graphite, the conductive agent conductive carbon black (SP), the thickener sodium carboxymethyl cellulose (CMC), and the binder styrene butadiene rubber (SBR) are mixed in a mass ratio of 96.2:1.2:1.2:1.4, and then deionized water is added as a solvent for mixing, and stirred under vacuum until the system becomes uniform to obtain a negative electrode slurry; the negative electrode slurry is evenly coated on both sides of the negative electrode collector copper foil, and then transferred to a 110°C oven for drying, and then rolled, slit, and cut to obtain a negative electrode sheet.

[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 evenly, and then vinylene carbonate, vinyl sulfate and lithium difluorophosphate were added to prepare an electrolyte.

[0156] 4. Preparation of diaphragm

[0157] PP film is used as the separator.

[0158] 5. Preparation of lithium-ion batteries

[0159] After drying, the negative electrode sheet and the positive electrode sheet prepared by the above steps are used together with the separator to prepare a wound electrode assembly by a winding machine, the positive electrode tab and the negative electrode tab are welded to the top cover, and the welded electrode assembly with the top cover is placed in an aluminum shell for packaging; after perfusing the electrolyte and forming to a constant capacity, a lithium-ion battery is obtained.

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

[0161] The battery packs prepared in the above examples and comparative examples were subjected to performance tests. The specific test items are as follows:

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

[0163] The insulating component in the lithium-ion battery uses the insulating component in the present application, and the lithium-ion battery is placed in the injection machine; the injection machine first evacuates the interior of the lithium-ion battery so that the air pressure inside the lithium-ion battery is below -90Kpa. At this time, the electrolyte has been stored in the injection cup. Since the interior of the lithium-ion battery is in a negative pressure state, the electrolyte flows into the interior of the lithium-ion battery; then the injection machine performs alternating positive and negative pressure cycles on the lithium-ion battery (positive pressure 180Kpa (30-60S), negative pressure -60Kpa (3-15S), cycle 4-12 times) so that the electrolyte can be fully injected into the lithium-ion battery, and the time required for the entire injection process is recorded as T; the insulating component in the lithium-ion battery uses a conventional insulating component (that is, no structure is set at the through hole of the insulating component), and the lithium-ion battery is subjected to the same injection operation, and the time required for the entire injection process is recorded as t, and the injection efficiency = t / T×100%.

[0164] 2. Test method for voltage of lithium-ion battery

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

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

[0167] Insert a connecting tube connected to an external pressure gauge into the injection hole and seal the injection hole. Use the connecting tube to fill helium into the interior of the lithium-ion battery and record the pressure displayed on the pressure gauge when the pressure relief valve is detonated.

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

[0169] The prepared lithium-ion battery is disassembled after being left to stand for a period of time, the disassembled insulating component is placed on a platform, the base of the height gauge is placed on the platform, the sliding rod of the height gauge is adjusted to make it contact with the surface between the through hole of the insulating component and the pole, the height gauge is moved, the readings of multiple points are recorded, and 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 dimension L1 mm of the first baffle 143 in the radial direction P, the dimension L2 mm of the second baffle 144 in the radial direction P, the maximum outline dimension D mm of the through hole 1411, the orthographic projection area S1 mm of each first baffle 143 on the reference plane O, and the maximum outline dimension D mm of the through hole 1411. 2 The orthographic projection area of ​​each second baffle 144 on the reference plane O is S3 mm 2 and the orthographic projection area S2 mm of the hole wall of through hole 1411 on reference plane O 2 The influence of the relationship between parameters on lithium-ion batteries.

[0171] Table 1 Parameters and test results of Examples 1 to 31 and Comparative Examples 1 to 4

[0172]

[0173]

[0174]

[0175] It can be seen from the data in Table 1 that: in Comparative Example 2, the specific parameters of the lithium-ion battery exceed the parameter range in this application. Compared with the lithium-ion batteries in Examples 1 to 16, the injection efficiency of the lithium-ion battery in Comparative Example 2 is significantly reduced, the injection effect is not good, and the lithium-ion battery does not show the corresponding performance, which does not meet the requirements; in Comparative Examples 1 and Comparative Examples 3, the specific parameters of the lithium-ion battery exceed the parameter range in this application. Compared with the lithium-ion batteries in Examples 1 to 16, the injection efficiency of the lithium-ion batteries in Comparative Examples 1 and Comparative Examples 3 is higher, but the voltage value of the lithium-ion battery in Comparative Examples 1 and Comparative Examples 3 decreases, the lithium-ion battery short-circuits, and the lithium-ion battery does not show the corresponding performance, which does not meet the requirements. The specific parameters of the lithium-ion battery in Comparative Example 5 exceed the parameter range in the present application. Compared with the lithium-ion batteries in Examples 17 to 32, the injection efficiency of the lithium-ion battery in Comparative Example 5 is significantly reduced, the injection effect is not good, and the lithium-ion battery does not show the corresponding performance, which does not meet the requirements; in Comparative Examples 4 and 6, the specific parameters of the lithium-ion battery exceed the parameter range in the present application. Compared with the lithium-ion batteries in Examples 17 to 32, the injection efficiency of the lithium-ion batteries in Comparative Examples 4 and 6 is higher, but the voltage values ​​of the lithium-ion batteries in Comparative Examples 4 and 6 decrease, the lithium-ion batteries are short-circuited, and the lithium-ion batteries do not show the corresponding performance, which does not meet the requirements.

[0176] It can be seen that the present application defines the orthographic projection area S1 mm of each first baffle 143 on the reference plane O. 2 and the orthographic projection area S2 mm of the hole wall of through hole 1411 on reference plane O 2 The ratio of is within the range of 0.0002 to 0.28, and the orthographic projection area S1 mm of each first baffle 143 on the reference plane O is limited. 2 At 0.051mm 2 ~71.2472mm 2 The orthographic projection area S2 mm of the hole wall defining the through hole 1411 on the reference plane O 2 At 7.065mm 2 ~254.34mm 2 The orthographic projection area S3 mm of each second baffle 144 on the reference plane O is limited within the range 2 and the orthographic projection area S2 mm of the hole wall of through hole 1411 on reference plane O 2 The ratio of is within 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 2The ratio of the dimension L1 mm of the first baffle 143 in the radial direction P to the maximum outline dimension D mm of the through hole 1411 is limited to be within the range of 0.01 to 1.67, the ratio of the dimension L2 mm of the second baffle 144 in the radial direction P to the maximum outline dimension D mm of the through hole 1411 is limited to be within the range of 0.017 to 0.47, the dimension L1 mm of the first baffle 143 in the radial direction P is limited to be within the range of 0.03 mm to 8.46 mm, the maximum outline dimension D mm of the through hole 1411 is limited to be within the range of 3 mm to 18 mm, the dimension L2 mm of the second baffle 144 in the radial direction P is limited to be within the range of 0.03 mm to 8.46 mm, the maximum outline dimension D mm of the through hole 1411 is limited to be within the range of 3 mm to 18 mm mm is in the range of 0.03mm~8.46mm to ensure the injection efficiency of the single cell 100; at the same time, it is ensured that the first baffle portion 143 can effectively block and buffer the electrolyte, reduce the direct impact of the electrolyte of the single cell 100 on the electrode assembly 120 during injection, thereby reducing the shedding of active materials on the positive and negative electrode sheets in the electrode assembly 120, and reducing the safety hazards of the single cell 100; at the same time, it is ensured that the first baffle portion 143 can effectively block the overlapping area of ​​the top cover 130 and the through hole 1411, avoid the ear of the electrode assembly 120 from extending into the through hole 1411 and contacting the top cover 130 to cause a short circuit in the single cell 100, reduce the short circuit risk between the electrode assembly 120 and the top cover 130, and ensure 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 of examples 33 to 46

[0179] <![CDATA[T2 / mm]]> <![CDATA[T1 / mm]]> <![CDATA[T2 / T1]]> Pressure relief valve detonation pressure / Mpa 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] It can be seen from the data in Table 2 that 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 show corresponding performance and does not meet the requirements.

[0181] It can be seen that the present application reasonably designs the structural dimensions of the insulating component 140 by limiting 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 within the range of 0.005 to 0.833, and limiting the distance T2 mm between the pressure relief boss 145 and the through hole 1411 within the range of 3 mm to 500 mm, so as to avoid the distance between the pressure relief boss 145 and the through hole 1411 being too close, so as to avoid the electrolyte impacting the pressure relief valve 160 when the single cell 100 is injected, causing the pressure relief valve 160 to loosen, thereby affecting the normal use of the pressure relief valve 160, thereby ensuring the safety performance of the single cell 100.

[0182] Table 3 shows the influence of the parameter relationship between the distance T3 mm between the pole 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 of examples 47 to 62

[0184] <![CDATA[T3 / mm]]> <![CDATA[T1 / mm]]> <![CDATA[T3 / T1]]> Flatness of the insulating member between the through hole and the pole / mm 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] It can be seen from the data in Table 3 that 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 component 140 in the lithium-ion battery in Example 62 is significantly increased, and the planar deformation of the insulating component 140 is large. The lithium-ion battery does not exhibit corresponding performance and does not meet the requirements.

[0186] It can be seen that the present application reasonably designs the structural dimensions of the insulating component 140 by limiting the ratio of the distance T3 mm between the pole 150 and the through hole 1411 to the dimension T1 mm of the insulating body 141 in the second direction X within the range of 0.0067 to 0.833, and limiting the distance T3 mm between the pole 150 and the through hole 1411 within the range of 4 mm to 500 mm, so as to ensure the overall flatness of the insulating component 140, thereby ensuring the tight assembly between the insulating component 140 and the top cover 130, and ensuring the structural stability between the various components of the single battery 100.

[0187] The introduction provided in the above steps is only used to help understand the method, structure and core idea of ​​the present application. For ordinary technicians in this technical field, without departing from the principles of the present application, several improvements and modifications can be made to the present application, and these improvements and modifications also fall within the scope of protection of the claims of the present application.

Claims

1. A single battery having a first direction and a reference plane perpendicular to the first direction, characterized in that: include: A housing is provided with a receiving cavity; An electrode assembly is disposed in the accommodating cavity; A top cover connected to one side of the shell in the first direction and covering the accommodating cavity, and a liquid injection hole is opened on the top cover; as well as An insulating component, the insulating component comprising: an insulating body, a plurality of guide parts and a plurality of first baffles, the insulating body being connected to a side of the top cover close to the electrode assembly, the insulating body being provided with a through hole, the through hole being communicated with the injection hole; the plurality of guide parts being connected to a side of the insulating body close to the electrode assembly, and the plurality of guide parts being arranged around the periphery of the through hole to form a guide channel with an opening, the guide channel being communicated with the through hole, the opening connecting the guide channel with the accommodating cavity; two adjacent guide parts being arranged at intervals to form a first guide opening between the two adjacent guide parts, the first guide opening connecting the guide channel with the accommodating cavity; each of the first baffles being respectively connected to a side of one of the guide parts close to the electrode assembly, the two adjacent first baffles being arranged at intervals, and the first baffles blocking at least part of the opening; The orthographic projection area of ​​each of the first baffles on the reference plane is S1 mm 2 The orthographic projection area of ​​the through hole wall on the reference plane is S2 mm 2 , satisfying: 0.0002≤S1 / S2≤0.

28.

2. The single cell according to claim 1, characterized in that: The orthographic projection area of ​​each of the first baffles on the reference plane is S1 mm 2 and the orthographic projection area of ​​the through hole wall on the reference plane S2 mm 2 It also satisfies: 0.04≤S1 / S2≤0.

2.

3. The single cell according to claim 2, characterized in that: The orthographic projection area of ​​each of the first baffles on the reference plane is S1 mm 2 Also satisfying: 0.051≤S1≤71.245; and / or, The orthographic projection area of ​​the through hole wall on the reference plane is S2 mm 2 Also satisfies: 7.065≤S2≤254.

34.

4. The single cell according to claim 2, characterized in that: The through hole has a radial direction perpendicular to the first direction; The dimension of the first baffle in the radial direction is L1 mm, the maximum outline dimension of the through hole is D mm, and the following conditions are satisfied: 0.01≤L1 / D≤0.47; or, The dimension L1 mm of the first baffle in the radial direction and the maximum outline dimension Dmm of the through hole also satisfy the following: 0.06≤L1 / D≤0.

18.

5. The single cell according to claim 4, characterized in that: The dimension L1mm of the first baffle in the radial direction 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 according to claim 1, characterized in that: The through hole has a central axis, the central axis extends along the first direction, and the radius of the through hole intersects the central axis; The plurality of flow guides are centrally symmetrically arranged about the central axis, and the plurality of first flow blocking portions are centrally symmetrically arranged about the central axis.

7. The single cell according to claim 6, characterized in that: The guide portion extends along the first direction; or, The guide portion is arranged to be inclined relative to a first direction, and in the first direction, along a direction from the insulating component toward the electrode assembly, a distance between the guide portion and the central axis of the through hole decreases.

8. The single cell according to claim 1, characterized in that: 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 is disposed in the through hole, and each of the second flow blocking portions is disposed between two adjacent flow guiding portions.

9. The single cell according to claim 8, characterized in that: The orthographic projection area of ​​each of the second baffles on the reference plane is S3 mm 2 , satisfying: 0.0002≤S3 / S2≤0.15; or, The orthographic projection area of ​​each of the second baffles on the reference plane is S3 mm 2 , satisfying: 0.021≤S3 / S2≤0.

097.

10. The single cell according to claim 9, characterized in that: The orthographic projection area of ​​each of the second baffles on the reference plane is S3 mm 2 Also satisfies: 0.046≤S3≤38.

151.

11. The single cell according to claim 9, characterized in that: The through hole has a radial direction perpendicular to the first direction; In the radial direction, the second flow blocking portion extends along the hole wall toward the center of the through hole; The dimension of the second baffle in the radial direction is L2 mm, satisfying: 0.017≤L2 / D≤0.47; or; A dimension L2 mm of the second baffle in the radial direction also satisfies: 0.06≤L2 / D≤0.

18.

12. The single cell according to claim 11, characterized in that: The dimension L2 mm of the second baffle in the radial direction also satisfies: 0.051≤L2≤8.46; or, A dimension L2 mm of the second baffle in the radial direction also satisfies: 0.36≤L2≤2.

16.

13. The single cell according to claim 1, characterized in that: The single battery also has a second direction intersecting with the first direction; The insulating member further includes: a pressure relief boss protruding from a side of the insulating body close to the electrode assembly, and the pressure relief boss is spaced apart from the through hole 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.

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

15. The single cell according to claim 13, characterized in that: The single cell further comprises: a pole, which is arranged on the top cover, and part of the pole passes through the insulating body and is electrically connected to the electrode assembly, and the through hole is located between the pole and the pressure relief boss; The distance between the pole and the through hole is T3 mm, satisfying: 0.0067≤T3 / T1≤0.

833.

16. The single cell according to claim 15, characterized in that: The distance T3 mm between the pole and the through hole also satisfies: 4≤T3≤500.

17. A battery pack, characterized in that: include: Box; as well as The single cell according to any one of claims 1 to 16, wherein the single cell is disposed in the box.

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