Secondary battery and electric device

Abstract

The invention discloses a secondary battery and a power utilization device, the secondary battery comprises a shell, an electrode assembly, a top cover plate, an insulating part and a convex part, the top cover plate is connected with the shell, and a liquid injection hole is formed in the top cover plate; the insulating part is connected with one side, facing the electrode assembly, of the top cover plate; the protruding piece comprises an extending part and a blocking part. The extending part is connected with the side, away from the top cover piece, of the insulating piece. The blocking part is connected to the side, away from the insulating part, of the extending part, and the orthographic projection of the blocking part on the top cover piece covers at least part of the liquid injection hole. At least one flow guide hole is formed in the extension part and is communicated with the liquid injection hole; the sum of the area of the at least one flow guide hole is S1 mm < 2 >, the area of the liquid injection hole is S2 mm < 2 >, and S1 / S2 is larger than or equal to 1 and smaller than or equal to 4. After the secondary battery meets the range that S1 / S2 is larger than or equal to 1 and smaller than or equal to 4, the liquid injection efficiency of the electrolyte is further improved while the strength of the protruding pieces is improved, and the production yield of the secondary battery is remarkably increased.

Description

[0001] This application is a divisional application of the invention patent application with application number 202411059056.4, application date August 2, 2024, and name “Secondary battery and electrical device”. Technical Field

[0002] The present application belongs to the field of battery technology, and specifically relates to secondary batteries and electrical devices. Background Art

[0003] The top cover assembly of the secondary battery is provided with an injection hole. When the electrode assembly is produced, the electrolyte needs to be injected into the electrode assembly through the injection hole. However, when the injection pressure and injection speed are too large, the force of the electrolyte directly impacting the diaphragm on the electrode assembly also increases synchronously, causing the diaphragm to collapse, resulting in the problem of short circuit between the positive and negative electrodes, resulting in a decrease in the quality rate of battery production. Usually, there is a boss on the top cover assembly to alleviate the impact of the electrolyte, but the structure and position of the boss will directly affect the injection efficiency, and if the strength of the boss itself is too low, it will be broken by the electrolyte and will not have a buffering effect. Summary of the invention

[0004] Purpose of the invention: The embodiments of the present application provide a secondary battery and an electrical device, which solve the problems of low liquid injection efficiency and easy damage of the boss by controlling the structure and position of the boss on the top cover assembly.

[0005] Technical solution: A secondary battery provided in an embodiment of the present application includes:

[0006] A housing having a receiving cavity;

[0007] An electrode assembly, wherein the electrode assembly is disposed in the accommodating cavity;

[0008] A top cover sheet, the top cover sheet is connected to the shell and covers the accommodating cavity, the top cover sheet has a thickness direction X, the top cover sheet is provided with a liquid injection hole, and the liquid injection hole penetrates the top cover sheet along the thickness direction X;

[0009] An insulating member, the insulating member is arranged in the accommodating cavity, and the insulating member is connected to a side of the top cover plate facing the electrode assembly, and the insulating member is provided with a through hole, the through hole penetrates the insulating member along the thickness direction X, and is connected to the injection hole;

[0010] A protruding member, the protruding member comprising an extension portion and a blocking portion, the extension portion being connected to a side of the insulating member away from the top cover sheet, and the extension portion being arranged around the through hole; the blocking portion being connected to a side of the extension portion away from the insulating member, and the orthographic projection of the blocking portion on the top cover sheet along the thickness direction X covering at least a portion of the injection hole; the extension portion being provided with at least one guide hole, the guide hole being communicated with the injection hole;

[0011] The total area of ​​the at least one guide hole is S1 mm 2 The area of ​​the injection hole is S2mm 2 , satisfying: 1≤S1 / S2≤4.

[0012] In some embodiments, the thickness of the extension portion is H1 mm, and the secondary battery further satisfies: 1.2≤H1×S1≤120.

[0013] In some embodiments, the secondary battery further satisfies: 2.4≤H1×S1≤30.

[0014] In some embodiments, the secondary battery further satisfies at least one of the following characteristics:

[0015] a) 0.6≤H1≤2;

[0016] b)2≤S1≤60.

[0017] In some embodiments, the insulating member includes an insulating body portion and first protrusions disposed on both sides of the insulating body portion, and the first protrusions are connected to a side of the insulating body portion facing the electrode assembly;

[0018] The insulating body portion has a first surface in the thickness direction X facing the top cover sheet and connected to the top cover sheet, the first protrusion has a second surface in the thickness direction X facing the electrode assembly, and the blocking portion has a third surface in the thickness direction X facing the electrode assembly; wherein, the first surface and the second surface have a maximum distance H mm in the thickness direction X, and the first surface and the third surface have a maximum distance H3 mm in the thickness direction X, satisfying: H3≤H2.

[0019] In some embodiments, the secondary battery further satisfies at least one of the following characteristics:

[0020] c)H3≤H2-1;

[0021] d)1≤H2≤10;

[0022] e)0.5≤H3≤8.

[0023] In some embodiments, the top cover sheet includes a top cover body and a second protrusion; the top cover body has a fourth surface and a fifth surface that are opposite to each other in the thickness direction X, and the fourth surface faces the electrode assembly and is connected to the first surface; the second protrusion is connected to the fourth surface and is arranged around the injection hole, and the second protrusion is located in the through hole; the second protrusion has a sixth surface facing the electrode assembly in the thickness direction X; wherein the first surface and the sixth surface have a maximum distance H4 mm in the thickness direction X, satisfying: H4<H3.

[0024] In some embodiments, the secondary battery further satisfies at least one of the following characteristics:

[0025] f)H3≥H4+1;

[0026] g)0.4<H4≤3.

[0027] In some embodiments, the insulating body portion further has a seventh surface facing the electrode assembly in the thickness direction X, and the seventh surface and the first surface are arranged opposite to each other in the thickness direction X;

[0028] The extension portion includes a plurality of extension segments arranged around the through hole; one end of the extension segment is connected to the seventh surface, and the end of the extension segment away from the seventh surface is connected to the blocking portion; the through hole has a radial direction Y perpendicular to the thickness direction X, the extension segment has an eighth surface away from the through hole and a ninth surface close to the through hole in the radial direction Y, and the extension segment also has a tenth surface located at the connection between the eighth surface and the ninth surface and connected to the eighth surface and the ninth surface respectively;

[0029] The secondary battery further comprises:

[0030] a first reinforcing member, wherein the first reinforcing member is connected to the tenth surface of the adjacent extension section, and the first reinforcing member, the extension section and the blocking portion jointly enclose the guide hole; or

[0031] The first reinforcement member is connected to the ninth surfaces of any two of the extension segments, and the extension segments, the blocking portion and the insulating body portion jointly enclose the guide hole.

[0032] In some embodiments, the insulating body portion further has a seventh surface facing the electrode assembly in the thickness direction X, and the seventh surface and the first surface are arranged opposite to each other in the thickness direction X;

[0033] The extension portion includes a plurality of extension segments arranged around the through hole, and the extension segments, the blocking portion and the insulating body portion together enclose the guide hole; one end of the extension segment is connected to the seventh surface, and one end of the extension segment away from the seventh surface is connected to the blocking portion; the through hole has a radial direction Y perpendicular to the thickness direction X, and the extension segment has an eighth surface away from the through hole in the radial direction Y;

[0034] The secondary battery further comprises:

[0035] A second reinforcement member is disposed in the accommodating cavity and is connected to the seventh surface and the eighth surface respectively.

[0036] In some embodiments, a plurality of the guide holes are disposed on the extension portion, and the plurality of guide holes are spaced apart along the circumference of the extension portion.

[0037] In some embodiments, the extension section includes a first connecting section and a first bending section, the first connecting section is connected to the seventh surface, the first bending section is connected to a side of the first connecting section away from the first bending section, and a side of the first bending section away from the first connecting section is connected to the blocking portion; wherein the first reinforcement member, the first connecting section, the first bending section and the blocking portion together enclose the guide hole.

[0038] In some embodiments, the blocking portion includes a second connecting section, a second bending section and a third connecting section; the second connecting section is connected to an end of the extension section away from the seventh surface, the second bending section is connected to a side of the second connecting section away from the extension section, and the third connecting section is connected to a side of the second bending section away from the second connecting section; wherein, the first reinforcement member, the extension section, the second connecting section, the second bending section and the third connecting section together enclose the guide hole.

[0039] In some embodiments, the present application also provides an electrical device, including the secondary battery, and the secondary battery is used to supply power to the electrical device.

[0040] Beneficial effect: A secondary battery according to an embodiment of the present application comprises: a shell having a receiving cavity; an electrode assembly, the electrode assembly being arranged in the receiving cavity; a top cover sheet, the top cover sheet being connected to the shell and covering the receiving cavity, the top cover sheet having a thickness direction X, the top cover sheet being provided with a liquid injection hole, the liquid injection hole penetrating the top cover sheet along the thickness direction X; an insulating member, the insulating member being arranged in the receiving cavity, and the insulating member being connected to a side of the top cover plate facing the electrode assembly, the insulating member being provided with a through hole, the through hole penetrating the insulating member along the thickness direction X, and being connected to the liquid injection hole; a protruding member, the protruding member comprising an extension portion and a blocking portion, the extension portion being connected to a side of the insulating member away from the top cover sheet, and the extension portion being arranged around the through hole; the blocking portion being connected to a side of the extension portion away from the insulating member, and the orthographic projection of the blocking portion on the top cover sheet along the thickness direction X covering at least part of the liquid injection hole; the extension portion being provided with at least one guide hole, the guide hole being connected to the liquid injection hole; wherein the total area of ​​the at least one guide hole is S1 mm 2 The area of ​​the injection hole is S2 mm 2 , satisfying: 1≤S1 / S2≤4. The present application provides a protrusion and the protrusion faces the injection hole, so that the electrolyte cannot directly impact the electrode assembly, but flows to the side instead, and flows out through the guide hole into the shell, thereby avoiding the problem of diaphragm collapse and short circuit of positive and negative electrodes; when the range of 1≤S1 / S2≤4 is met, the strength of the protrusion is improved while further improving the injection efficiency of the electrolyte, so that the production rate of secondary batteries is significantly improved.

[0041] The electric device of the embodiment of the present application may include all the technical features and beneficial effects of the above-mentioned secondary battery, which will not be described in detail here. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For those skilled in the art, other drawings can be obtained based on these drawings without creative work.

[0043] Figure 1 A schematic diagram of the secondary battery structure provided in an embodiment of the present application;

[0044] Figure 2 A schematic diagram of the structure of an insulating member and a protruding member provided in an embodiment of the present application;

[0045] Figure 3 for Figure 2 Schematic cross-sectional view of ;

[0046] Figure 4 for Figure 2 A local enlarged schematic diagram of the middle A;

[0047] Figure 5 for Figure 4 A schematic cross-sectional view of the middle raised member;

[0048] Figure 6 A schematic diagram of another insulating member and a protruding member structure provided in an embodiment of the present application;

[0049] Figure 7 for Figure 6 Schematic cross-sectional view of ;

[0050] Figure 8 for Figure 6 A partial enlarged schematic diagram of point B in the middle;

[0051] Fig. 9 for Figure 8 A schematic cross-sectional view of the middle raised member;

[0052] Fig.10 A schematic diagram of another insulating member and a protruding member structure provided in an embodiment of the present application;

[0053] Fig.11 for Fig.10 an enlarged schematic diagram of the middle raised member;

[0054] Fig.12 A schematic diagram of another insulating member and a protruding member structure provided in an embodiment of the present application;

[0055] Fig.13 for Fig.12 an enlarged schematic diagram of the middle raised member;

[0056] Fig.14 A schematic diagram of another insulating member and a protruding member structure provided in an embodiment of the present application;

[0057] Fig.15 for Fig.14 an enlarged schematic diagram of the middle raised member;

[0058] Fig.16 A schematic diagram of another insulating member and a protruding member structure provided in an embodiment of the present application;

[0059] Fig.17 for Fig.16 an enlarged schematic diagram of the middle raised member;

[0060] Fig.18 A schematic diagram of another insulating member and a protruding member structure provided in an embodiment of the present application;

[0061] Fig.19 for Fig.18 an enlarged schematic diagram of the middle raised member;

[0062] Fig. 20A schematic diagram of another insulating member and a protruding member structure provided in an embodiment of the present application;

[0063] Fig.21 for Fig. 20 an enlarged schematic diagram of the middle raised member;

[0064] Figure numerals: 10-shell, 101-accommodating cavity, 20-electrode assembly, 30-top cover sheet, 301-liquid injection hole, 302-top cover body, 303-second protrusion, 3021-fourth surface, 3022-fifth surface, 3031-sixth surface, 40-insulating member, 401-through hole, 402-insulating body, 4021-first surface, 4022-seventh surface, 403-first protrusion, 4031-second surface , 50-protrusion, 501-extension portion, 5010-extension section, 5011-eighth surface, 5012-ninth surface, 4013-tenth surface, 5014-first connecting section, 5015-first bending section, 502-blocking portion, 5021-third surface, 5022-second connecting section, 5023-second bending section, 5024-third connecting section, 503-guide hole, 60-first reinforcement member, 70-second reinforcement member. DETAILED DESCRIPTION

[0065] The technical solutions in the embodiments of the present application will be described clearly and completely below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present application.

[0066] In the description of the present application, it should be understood that the terms "length", "width", "thickness", "upper", "lower", "top", "bottom", "inside", "outside", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, rather than indicating or implying 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 the description of the present application, "multiple" means two or more, and at least one means one, two or more, unless otherwise clearly and specifically defined.

[0067] As a key component of power batteries, the top cover structure of power batteries has a significant impact on the energy density, economy and safety of power batteries. The top cover of the power battery is provided with an injection hole. When the battery is produced, the electrolyte is injected into the shell through the injection hole. At present, the industry adopts large injection pressure and injection speed to improve the production efficiency of the battery. However, when the injection pressure and injection speed are too large, the force of the electrolyte directly impacting the diaphragm on the top of the bare electrode assembly also increases synchronously, causing the diaphragm to collapse and the problem of short-circuiting the positive and negative electrodes, which reduces the quality rate of battery production. Usually, a boss is provided on the top cover assembly to alleviate the impact of the electrolyte, but the structure and position of the boss will directly affect the injection efficiency, and if the strength of the boss itself is too low, it will be broken by the electrolyte and will not have a buffering effect.

[0068] See also Figure 1 , Figure 2 , Figure 3 , Figure 4 and Figure 5 The present embodiment provides a secondary battery, comprising: a shell 10, an electrode assembly 20, a top cover sheet 30, an insulating member 40 and a protruding member 50; the shell 10 has a receiving cavity 101; the electrode assembly 20 is arranged in the receiving cavity 101; the top cover sheet 30 is connected to the shell 10 and covers the receiving cavity 101, the top cover sheet 30 has a thickness direction X, the top cover sheet 30 is provided with a liquid injection hole 301, and the liquid injection hole 301 penetrates the top cover sheet 30 along the thickness direction X; the insulating member 40 is arranged in the receiving cavity 101, and the insulating member 40 is connected to the side of the top cover sheet 30 facing the electrode assembly 20, and the insulating member 40 is provided with a through hole 401, and the through hole 401 is along the thickness direction X. The protruding member 50 includes an extension portion 501 and a blocking portion 502, wherein the extension portion 501 is connected to a side of the insulating member 40 away from the top cover sheet 30, and the extension portion 501 is arranged around the through hole 401; the blocking portion 502 is connected to a side of the extension portion 501 away from the insulating member 40, and the orthographic projection of the blocking portion 502 on the top cover sheet 30 along the thickness direction X covers at least part of the injection hole 301; at least one guide hole 503 is provided on the extension portion 501, and the guide hole 503 is connected to the injection hole 301; wherein the total area of ​​the at least one guide hole 503 is S1 mm 2 , the area of ​​the injection hole 301 is S2 mm 2 , satisfying: 1≤S1 / S2≤4.

[0069] In some embodiments, the ratio of S1 / S2 can be any one of 1, 1.5, 2, 2.5, 3, 3.5, and 4, or a range between any two values. If the ratio of S1 / S2 is too small, since the area of ​​the guide hole 503 is smaller than that of the injection hole 301, the ability of the guide hole 503 to pass the electrolyte is worse than that of the injection hole 301, which becomes a bottleneck of the injection speed and reduces the injection efficiency; if the ratio of S1 / S2 is too large, the area of ​​the guide hole 503 is too large, so that the area of ​​the remaining part of the extension 501 is relatively reduced, resulting in a decrease in the strength of the protrusion 50, which is easily damaged and ineffective due to the impact of the electrolyte injection.

[0070] In some embodiments, the thickness of the extension portion 501 is H1 mm, and the secondary battery further satisfies: 1.2≤H1×S1≤120.

[0071] It should be noted that the through hole 401 has a radial direction Y perpendicular to the thickness direction X. When the thickness of the extension portion 501 is equal everywhere, the thickness of the extension portion 501 is equal to the dimension of the through hole in the radial direction Y. When the thickness of the extension portion is uneven, the minimum thickness of the extension portion 501 is taken as the thickness dimension of the extension portion 501.

[0072] It should be noted that in the secondary battery of this embodiment, the insulating member 40 can be understood as the lower plastic, which is used for insulation between the top cover sheet 30 and the electrode assembly 20; the injection hole 301 on the top cover sheet 30 is used to inject electrolyte, and the through hole 401 on the insulating member 40 is connected with the injection hole 301, so that the electrolyte enters the accommodating cavity 101; the protrusion 50 is arranged on the side of the insulating member 40 facing the electrode assembly 20, wherein the extension portion 501 of the protrusion 50 is arranged around the through hole 401, and is used to determine the protrusion. The protruding member 50 is at a position relative to the insulating member 40; the orthographic projection of the blocking portion 502 on the top cover sheet 30 along the thickness direction X covers at least part of the injection hole 301, which can ensure that at least part of the blocking portion 502 is directly opposite to the injection hole 301, so as to achieve the effect of blocking and buffering the injected electrolyte; in addition, a guide hole 503 is provided on the extension portion 501, which further realizes the diversion of the electrolyte, so that the electrolyte enters the shell 10 through other paths to interact with the electrode assembly 20. It can be understood that the present application provides a protruding member 50 and the protruding member 50 is directly opposite to the injection hole 301, so that the electrolyte cannot directly impact the electrode assembly 20, but instead diverts to the side and flows out through the guide hole 503 and enters the inside of the shell 10, thereby avoiding the problem of diaphragm collapse and short circuit of positive and negative electrode sheets. In addition, H1 and S1 further define the thickness of the extension 501 in the radial direction Y and the area of ​​the guide hole 503, that is, H1×S1 can further reflect the volume of the guide hole 503. If the value of H1×S1 is too small, it means that the volume of the guide hole 503 is too small, which will reduce the injection efficiency; if the value of H1×S1 is too large, it means that the volume of the guide hole 503 is too large, resulting in a reduction in the volume of the remaining part of the extension 501, which reduces the strength of the protrusion 50 and is easily damaged and ineffective due to the impact force of the electrolyte injection. Therefore, when the range of 1.2≤H1×S1≤120 is met, the strength of the protrusion 50 is improved while the injection efficiency of the electrolyte is further improved, so that the production rate of secondary batteries is significantly improved.

[0073] It should be further explained that the thickness direction X and the radial direction Y are respectively Figure 3 and Figure 4 The direction indicated by the arrow in the figure shall prevail. Although not marked in other figures, Figure 3 and Figure 4 The directions indicated are unified.

[0074] In some embodiments, the value of H1×S1 can be any value of 1.2, 1.5, 1.8, 2, 2.5, 3, 3.5, 4, 4.5, 5, 6, 7, 8, 9, 10, 15, 20, 25, 30, 35, 40, 45, 50, 60, 70, 80, 90, 100, 110, 120, or a range between any two values.

[0075] In some embodiments, the H1×S1 secondary battery further satisfies: 2.4≤H1×S1≤30. That is, H1×S1 can be any value of 2.4, 2.5, 2.6, 2.7, 2.8, 2.9, 3, 4, 5, 6, 7, 8, 9, 10, 12, 15, 18, 20, 22, 25, 28, 30, or a range between any two values.

[0076] In some embodiments, the secondary battery further satisfies: 0.6≤H1≤2; for example, the value of H1 mm can be any one of 0.6, 0.7, 0.8, 0.9, 1, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, 2, or a range between any two values. When H1 mm satisfies the above range, the structural strength of the protrusion 50 can be further guaranteed.

[0077] In some embodiments, the secondary battery further satisfies: 2≤S1≤60; for example, S1 mm 2 The value can be any one of 2, 3, 4, 5, 6, 7, 8, 9, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60 or a range between any two values. 2 When the above range is met, the electrolyte can be further maintained to have a high injection efficiency.

[0078] In some embodiments, see further Figure 2 , Figure 3 and Figure 5 The insulating member 40 includes an insulating body portion 402 and first protruding portions 403 provided on both sides of the insulating body portion 402, the first protruding portion 403 is connected to a side of the insulating body portion 402 facing the electrode assembly 20; the insulating body portion 402 has a first surface 4021 facing the top cover sheet 30 and connected to the top cover sheet 30 in the thickness direction X, the first protruding portion 403 has a second surface 4031 facing the electrode assembly 20 in the thickness direction X, and the blocking portion 502 has a third surface 5021 facing the electrode assembly 20 in the thickness direction X; wherein, the first surface 4021 and the second surface 4031 have a maximum distance H2 mm in the thickness direction X, and the first surface 4021 and the third surface 5021 have a maximum distance H3 mm in the thickness direction X, satisfying: H3≤H2.

[0079] It should be noted that, see Figure 3Since the first protrusions 403 at both ends of the insulating member 40 are used to contact the electrode assembly 20 and play a role in fixing the electrode assembly 20, the relationship between H3 and H2 needs to meet certain requirements. If H3 is greater than H2, the protrusion 50 will be inserted into the electrode assembly 20. When the electrode assembly 20 vibrates, the protrusion 50 will cause the diaphragm to sag or the pole piece to bend, resulting in a short circuit in the electrode assembly 20.

[0080] In some embodiments, the secondary battery further satisfies: H3≤H2-1, so as to prevent the boss structure from causing the diaphragm to collapse or the pole piece to bend under the vibration condition of the battery cell, thereby causing a short circuit in the battery cell.

[0081] In some embodiments, the secondary battery further satisfies: 1≤H2≤10; for example, the value of H2 mm can be any one of 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 or a range between any two values. When H2 mm satisfies the above range, the height of the protrusion 50 can be further ensured to be within a reasonable use range.

[0082] In some embodiments, the secondary battery further satisfies: 0.5≤H3≤8; for example, the value of H3 mm can be any one of 0.5, 1, 2, 3, 4, 5, 6, 7, and 8, or a range between any two values. When H3 mm satisfies the above range, it can be avoided that the first protrusion 403 is too short to fix the electrode assembly 20, or is too long to occupy too much space in the accommodation cavity.

[0083] In some embodiments, see Figure 6 , Figure 7 , Figure 8 and Fig. 9 The top cover sheet 30 includes a top cover body 302 and a second protrusion 303; the top cover body 302 has a fourth surface 3021 and a fifth surface 3022 that are opposite to each other in the thickness direction X, and the fourth surface 3021 faces the electrode assembly 20 and is connected to the first surface 4021; the second protrusion 303 is connected to the fourth surface 3021 and is arranged around the injection hole 301, and the second protrusion 303 is located in the through hole 401; the second protrusion 303 has a sixth surface 3031 facing the electrode assembly 20 in the thickness direction X; wherein the first surface 4021 and the sixth surface 3031 have a maximum distance H4 mm in the thickness direction X, satisfying: H4<H3.

[0084] It is understandable that in order to achieve the sealing of the injection hole 301, a second protrusion 303 needs to be provided on the top cover sheet 30 to facilitate the positioning of the sealing nail and achieve the sealing effect. After the second protrusion 303 is provided, it is necessary to further limit the range of H4<H3, otherwise the protrusion 50 and the second protrusion 303 will interfere with each other and cannot be assembled and produced. In addition, after the injection process is completed, the injection hole 301 will be sealed by a sealing nail. To ensure the sealing effect, the sealing nail generally extends out of the sixth surface 3031 of the second protrusion 303. To ensure the assembly of the sealing nail, H3 needs to be higher than H4 by the clearance distance of the nail.

[0085] In some embodiments, the secondary battery further satisfies: H3≥H4+1, which can ensure the assembly of the sealing nails.

[0086] In some embodiments, the secondary battery further satisfies: 0.4<H4≤3; for example, the value of H4 mm can be any one of 0.41, 0.45, 0.5, 0.6, 0.7, 0.8, 0.9, 1, 1.5, 2, 2.5, 3 or a range between any two values. This is because in order to ensure that the sealing nail and the injection hole 301 have sufficient sealing length to ensure airtightness, H4 needs to meet the above range. If H4 is too small or too large, the battery airtightness will fail.

[0087] In some embodiments, the area of ​​the injection hole is S2 mm 2 Further satisfying: 2≤S2≤15; for example, S2 mm 2 The value of can be any value among 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15 or a range between any two values.

[0088] In some embodiments, see further Fig. 9 The projection of the blocking portion 502 along the thickness direction X on the top cover sheet 30 covers the injection hole. Further, the projection area of ​​the blocking portion 502 along the thickness direction X on the top cover sheet 30 is S3 mm. 2 , the secondary battery further satisfies: 1≤S3 / S2≤6; for example, the value of S3 / S2 can be any one of 1, 2, 3, 4, 5, 6 or a range between any two values. If the ratio of S3 / S2 is too small, since the area of ​​the blocking portion 502 is smaller than the area of ​​the injection hole 301, it cannot completely block the electrolyte from directly impacting the electrode assembly from the injection hole 301, causing the diaphragm to collapse and the problem of short circuit between the positive and negative electrodes; if the ratio of S3 / S2 is too large, the protrusion 50 is too large, resulting in excessive internal space of the shell 10 being occupied. Among them, S3 mm 2 Satisfies: 2≤S3≤90, for example, S3 mm 2The value of can be any value among 2, 3, 4, 5, 6, 7, 8, 9, 10, 20, 30, 40, 50, 60, 70, 80, 90 or a range between any two values.

[0089] It should be noted that some common dimension measurement methods can be selected to measure H1, H2, H3, H4 and S1, S2 and S3; for example, for the thickness H1 of the extension 501, a vernier caliper, a micrometer or other measuring tools can be used to measure the corresponding dimensions. When the extension 501 is an irregular shape, it can also be measured by image processing, for example, an image of the extension 501 can be obtained, the image can be loaded using image processing software and measured using the software. Alternatively, it can also be measured by projection, using a projection measuring device (such as a digital microscope or an image measuring instrument) to obtain the image of the extension 501 and measure the corresponding dimensions. The methods for obtaining other H2, H3, and H4 are similar. Correspondingly, for the area S1 of the guide hole 503, the shape of the hole can also be obtained by projection, and the area can be calculated based on the corresponding shape. The test methods for other S2 and S3 are also the same.

[0090] In some embodiments, see further Figure 3 , Figure 7 , Figure 8 and Fig. 9 The insulating body 402 further has a seventh surface 4022 facing the electrode assembly 20 in the thickness direction X, and the seventh surface 4022 and the first surface 4021 are arranged in opposite directions in the thickness direction X; the extension portion 501 includes a plurality of extension segments 5010 arranged around the through hole 401; one end of the extension segment 5010 is connected to the seventh surface 4022, and the end of the extension segment 5010 away from the seventh surface 4022 is connected to the blocking portion 502; the extension segment 5010 has a radial direction Y away from the through hole 401 The eighth surface 5011 and the ninth surface 5012 close to the through hole 401, the extension section 5010 also has a tenth surface 4013 located at the connection between the eighth surface 5011 and the ninth surface 5012 and respectively connected to the eighth surface 5011 and the ninth surface 5012; the secondary battery also includes: a first reinforcement 60, the first reinforcement 60 is connected to the tenth surface 4013 of the adjacent extension section 5010, and the first reinforcement 60, the extension section 5010 and the blocking portion 502 jointly enclose the guide hole 503. It can be understood that by providing the first reinforcement 60, the strength of the protrusion 50 can be further improved, and the protrusion 50 can be prevented from being damaged and failing due to the impact force of the electrolyte injection, so that the production efficiency of the battery is significantly improved. It should be further explained that, see Figure 8 , Figure 8 In the structure, the guide hole 503 is enclosed by the first reinforcement member 60, so it is necessary to ensure that the guide hole 503 meets the range specified in S1.

[0091] In some embodiments, the first reinforcement member 60 is connected to the ninth surface 5012 of any two extension segments 5010 (not shown in the figure), and the extension segment 5010, the blocking portion 502 and the insulating body portion 402 together enclose the guide hole 503. At this time, the first reinforcement member 60 can be understood as being disposed in the guide space enclosed by the extension segment 5010 and the blocking portion 502, and the area of ​​the guide hole 503 will not be affected by the first reinforcement member 60.

[0092] In some embodiments, see further Fig.10 and Fig.11 The insulating body part 402 also has a seventh surface 4022 facing the electrode assembly 20 in the thickness direction X, and the seventh surface 4022 and the first surface 4021 are arranged in opposite directions in the thickness direction X; the extension part 501 includes a plurality of extension sections 5010 arranged around the through hole 401, and the extension sections 5010, the blocking part 502 and the insulating body part 402 jointly enclose the guide hole 503; one end of the extension section 5010 is connected to the seventh surface 4022, and the end of the extension section 5010 away from the seventh surface 4022 is connected to the blocking part 502; the extension section 5010 has an eighth surface 5011 away from the through hole 401 in the radial direction Y; the secondary battery also includes: a second reinforcement member 70, the second reinforcement member 70 is arranged in the accommodating cavity 101, and is respectively connected to the seventh surface 4022 and the eighth surface 5011. It should be noted that, Fig.10 and Figure 6 The difference is that the location of the reinforcement structure is different. Fig.10 In the embodiment, the second reinforcement member 70 can further improve the strength of the protrusion member 50, and prevent the protrusion member 50 from being damaged and failing due to the impact of the electrolyte injection, so that the production rate of the battery is significantly improved. Fig.10 In the embodiment, the second reinforcement member 70 also realizes the connection between the extension section 5010 and the insulating body portion 402 , can provide support, and further improve the structural strength of the protrusion 50 .

[0093] In some embodiments, see further Fig.12 and Fig.13 The extension portion 501 includes four extension sections 5010 and the four extension sections 5010 uniformly surround the through hole 401; at this time, the gap between adjacent extension sections 5010 is a guide hole 503; the four guide holes 503 are arranged on the extension portion 501 at an interval of 90°, and the injection efficiency can be further improved by increasing the number of guide holes 503 without affecting the overall structural strength of the protrusion 50.

[0094] In some embodiments, see further Fig.14 and Fig.15 ,exist Fig.12On the basis of the structure, four corresponding second reinforcement members 70 are further provided at each extension section 5010 . The provided second reinforcement members 70 can provide support for the extension section 5010 , thereby further improving the strength of the protrusion 50 .

[0095] In some embodiments, see further Fig.16 and Fig.17 The extension portion 501 is provided with a plurality of guide holes 503, and the plurality of guide holes 503 are arranged at intervals along the circumference of the extension portion 501. It can be understood that the plurality refers to a number of two or more. Fig.16 In the embodiment, the number of the guide holes 503 is multiple, and the multiple guide holes 503 are arranged in a closely arranged manner in the circumference of the extension portion 501. Here, the area S1 can be understood as the sum of the areas of the multiple guide holes 503. Fig.16 and Fig.17 The arrangement can make the connected area on the extension part 501 more, so as to further improve the strength of the protrusion 50. At the same time, the electrolyte enters the interior of the housing 10 from all directions through the guide holes 503, so that the electrolyte can enter more evenly.

[0096] In some embodiments, see further Fig.18 and Fig.19 The extension section 5010 includes a first connection section 5014 and a first bending section 5015, wherein the first connection section 5014 is connected to the seventh surface 4022, the first bending section 5015 is connected to the side of the first connection section 5014 away from the seventh surface 4022, and the side of the first bending section 5015 away from the first connection section 5014 is connected to the blocking portion 502; wherein the first reinforcing member 60, the first connection section 5014, the first bending section 5015 and the blocking portion 502 together enclose the guide hole 503. It can be understood that the first bending section 5015 is elastic and can buffer the impact force generated by the electrolyte. When the electrolyte is injected into the shell 10 through the injection hole 301 and the electrolyte impacts the protruding member 50, the first bending section 5015 can release part of the impact through deformation, thereby enhancing the mechanical properties of the protruding member 50.

[0097] In some embodiments, see further Fig. 20 and Fig.21, the blocking portion 502 includes a second connecting section 5022, a second bending section 5023 and a third connecting section 5024; the second connecting section 5022 is connected to one end of the extension section 5010 away from the seventh surface 4022, the second bending section 5023 is connected to one side of the second connecting section 5022 away from the extension section 5010, and the third connecting section 5024 is connected to one side of the second bending section 5023 away from the second connecting section 5022; wherein, the first reinforcing member 60, the extension section 5010, the second connecting section 5022, the second bending section 5023 and the third connecting section 5024 together enclose the guide hole 503. It can be understood that the second bending section 5023 is also elastic and can buffer the impact force generated by the electrolyte. When the electrolyte is injected into the shell 10 through the injection hole 301 and the electrolyte impacts the protruding member 50, the second bending section 5023 can release part of the impact through deformation, thereby enhancing the mechanical properties of the protruding member 50.

[0098] In some embodiments, the present application also provides an electrical device, including the secondary battery provided in this embodiment, and the secondary battery is used to power the electrical device. Among them, the electrical device can be an application device such as a vehicle, a mobile phone, a portable device, a laptop computer, a ship, a spacecraft, an electric toy, and an electric tool. The vehicle can be a new energy vehicle, and the new energy vehicle can be a pure electric vehicle, a hybrid vehicle, or an extended-range vehicle, etc.; the spacecraft includes an airplane, a rocket, a space shuttle, and a spacecraft, etc.; the electric toy includes a fixed or mobile electric toy, for example, a game console, an electric car toy, an electric ship toy, and an electric airplane toy, etc.; the electric tool includes a metal cutting electric tool, a grinding electric tool, an assembly electric tool, and an electric tool for railways, for example, an electric drill, an electric grinder, an electric wrench, an electric screwdriver, an electric hammer, an impact drill, a concrete vibrator, and an electric planer, etc. The embodiment of the present application does not impose any special restrictions on the above-mentioned electrical devices.

[0099] Provide examples 1-10, the specific structure is as follows Figure 1-Figure 5 As shown, the structural parameters of Examples 1-10 are shown in Table 1, and Examples 1-10 satisfy the range of 1.2≤H1×S1≤120. Comparative Example 1-2 is provided, and the structure is the same as that of Example 1, but Comparative Example 1-2 does not satisfy the range of 1.2≤H1×S1≤120. The batteries of Examples 1-5 and Comparative Example 1-2 are subjected to performance tests, and the tested performance includes the injection efficiency and whether the injection pressure causes the protrusion 50 to be damaged. Among them, 280g of electrolyte is injected into the secondary battery at a pressure of 0.3MPa, and the time required is measured. The electrolyte is injected into the secondary battery at a pressure of 0.3MPa, and 100 secondary batteries in each embodiment are grouped together, and the number of broken protrusions in each group is measured.

[0100] Table 1

[0101]

[0102] Referring to Table 1, compared with comparative example 1-2, the secondary battery of embodiment 1-10 satisfies the range of 1.2≤H1×S1≤120, has a shorter injection time, and the protrusions are less likely to be damaged, thereby improving the strength of the protrusions 50 and further improving the injection efficiency of the electrolyte.

[0103] Embodiments 11-14 are further provided, wherein the structure of Embodiments 11-14 is the same as that of Embodiment 1, except that the ranges of H2 mm and H3 mm are different. However, both Embodiments 1 and 11-14 satisfy H3≤H2. Comparative Examples 3-4 are further provided, and the specific structure is the same as that of Comparative Example 1, Comparative Example 1 satisfies the range of H3≤H2, but Comparative Example 3-4 does not satisfy the range of H3≤H2. The batteries of Embodiment 1, Comparative Example 1, Embodiments 11-14 and Comparative Examples 3-4 are subjected to performance tests, and the test performance includes: whether the electrode assembly is subjected to the mechanical force of the protrusion under vibration conditions, causing the diaphragm to collapse. See Table 2 for specific test results.

[0104] Table 2

[0105]

[0106]

[0107] Referring to Table 2, it can be seen from the tests of Example 1 and Examples 11-14 that when the secondary battery further satisfies H3≤H2, the protrusion 50 can be avoided from being inserted into the electrode assembly 20, and when the electrode assembly 20 vibrates, the protrusion 50 causes the diaphragm to collapse; however, it can be seen from the results of Comparative Examples 1, 3 and 4 that when the range of H3≤H2 is not satisfied, the mechanical force of the protrusion will cause the diaphragm to collapse.

[0108] Further provided are embodiments 15-19, wherein the structures of embodiments 15-19 are as follows Figure 5-Figure 9 As shown. Among them, Examples 15-19 satisfy the range of 1.2≤H1×S1≤120, and Examples 15-19 also satisfy H4<H3. Comparative Examples 5-7 are further provided, and the specific structure is the same as that of Example 15, except that Comparative Example 5 does not satisfy the range of 1.2≤H1×S1≤120 but satisfies H4<H3, but Comparative Example 5-6 does not satisfy the range of 1.2≤H1×S1≤120 and H4<H3. The batteries of Examples 15-19 and Comparative Examples 5-6 were subjected to performance tests, and the test performance included: whether the insulating part and the top cover sheet cannot be assembled due to interference in the injection hole area. See Table 3 for specific test results.

[0109] Table 3

[0110]

[0111]

[0112] Referring to Table 3, it can be seen from the tests of Examples 15-19 that when the secondary battery further satisfies H4<H3, the problem of whether the insulating member and the top cover sheet cannot be assembled due to interference in the injection hole area can be avoided; but from the results of Comparative Examples 5-7, it can be seen that when the range of H4<H3 is not satisfied, the protrusion 50 and the second protrusion 303 will interfere with each other and cannot be assembled and produced.

[0113] The secondary battery and the electrical device provided in the embodiments of the present application are introduced in detail above, and the principles and implementation methods of the present application are explained by using specific examples. The description of the above embodiments is only used to help understand the technical solution and its core idea of ​​the present application. Ordinary technicians in this field should understand that they can still modify the technical solutions recorded in the aforementioned embodiments, or replace some of the technical features therein with equivalents; and these modifications or replacements do not make the essence of the corresponding technical solution deviate from the scope of the technical solution of the embodiments of the present application.

Claims

1. A secondary battery, characterized in that: include: A housing having a receiving cavity; An electrode assembly, wherein the electrode assembly is disposed in the accommodating cavity; A top cover sheet, the top cover sheet is connected to the shell and covers the accommodating cavity, the top cover sheet has a thickness direction X, the top cover sheet is provided with a liquid injection hole, and the liquid injection hole penetrates the top cover sheet along the thickness direction X; An insulating member, the insulating member is disposed in the accommodating cavity, and the insulating member is connected to a side of the top cover sheet facing the electrode assembly, and the insulating member is provided with a through hole, the through hole penetrates the insulating member along the thickness direction X, and is connected to the injection hole; A protruding member, the protruding member comprising an extension portion and a blocking portion, the extension portion being connected to a side of the insulating member away from the top cover sheet, and the extension portion being arranged around the through hole; the blocking portion being connected to a side of the extension portion away from the insulating member, and the orthographic projection of the blocking portion on the top cover sheet along the thickness direction X covering at least a portion of the injection hole; the extension portion being provided with at least one guide hole, the guide hole being communicated with the injection hole; The total area of ​​the at least one guide hole is S1 mm 2 The area of ​​the injection hole is S2mm 2 , satisfying: 1≤S1 / S2≤4.

2. The secondary battery according to claim 1, characterized in that: The thickness of the extension portion is H1 mm, and the secondary battery further satisfies: 1.2≤H1×S1≤120.

3. The secondary battery according to claim 2, characterized in that: The secondary battery further satisfies: 2.4≤H1×S1≤30.

4. The secondary battery according to claim 2, characterized in that: The secondary battery further satisfies at least one of the following characteristics: a) 0.6≤H1≤2; b)2≤S1≤60.

5. The secondary battery according to claim 1, characterized in that: The insulating member comprises an insulating body portion and first protruding portions provided on both sides of the insulating body portion, wherein the first protruding portions are connected to a side of the insulating body portion facing the electrode assembly; The insulating body portion has a first surface in the thickness direction X facing the top cover sheet and connected to the top cover sheet, the first protrusion has a second surface in the thickness direction X facing the electrode assembly, and the blocking portion has a third surface in the thickness direction X facing the electrode assembly; wherein, the first surface and the second surface have a maximum distance H2 mm in the thickness direction X, and the first surface and the third surface have a maximum distance H3 mm in the thickness direction X, satisfying: H3≤H2.

6. The secondary battery according to claim 5, characterized in that: The secondary battery further satisfies at least one of the following characteristics: c)H3≤H2-1; d)1≤H2≤10; e)0.5≤H3≤8.

7. The secondary battery according to claim 5, characterized in that: The top cover sheet includes a top cover body and a second protrusion; the top cover body has a fourth surface and a fifth surface that are opposite to each other in the thickness direction X, and the fourth surface faces the electrode assembly and is connected to the first surface; the second protrusion is connected to the fourth surface and is arranged around the injection hole, and the second protrusion is located in the through hole; the second protrusion has a sixth surface facing the electrode assembly in the thickness direction X; wherein the first surface and the sixth surface have a maximum distance H4 mm in the thickness direction X, satisfying: H4<H3.

8. The secondary battery according to claim 7, characterized in that: The secondary battery further satisfies at least one of the following characteristics: f)H3≥H4+1; g)0.4<H4≤3.

9. The secondary battery according to claim 5, characterized in that: The insulating body portion further has a seventh surface facing the electrode assembly in the thickness direction X, and the seventh surface and the first surface are arranged opposite to each other in the thickness direction X; The extension portion includes a plurality of extension segments arranged around the through hole; one end of the extension segment is connected to the seventh surface, and the end of the extension segment away from the seventh surface is connected to the blocking portion; the through hole has a radial direction Y perpendicular to the thickness direction X, the extension segment has an eighth surface away from the through hole and a ninth surface close to the through hole in the radial direction Y, and the extension segment also has a tenth surface located at the connection between the eighth surface and the ninth surface and connected to the eighth surface and the ninth surface respectively; The secondary battery further comprises: a first reinforcement member, wherein the first reinforcement member is connected to the tenth surface of the adjacent extension section, and the first reinforcement member, the extension section and the blocking portion jointly enclose the guide hole; or The first reinforcement member is connected to the ninth surfaces of any two of the extension segments, and the extension segments, the blocking portion and the insulating body portion jointly enclose the guide hole.

10. The secondary battery according to claim 5, characterized in that: The insulating body portion further has a seventh surface facing the electrode assembly in the thickness direction X, and the seventh surface and the first surface are arranged opposite to each other in the thickness direction X; The extension portion includes a plurality of extension segments arranged around the through hole, and the extension segments, the blocking portion and the insulating body portion together enclose the guide hole; one end of the extension segment is connected to the seventh surface, and one end of the extension segment away from the seventh surface is connected to the blocking portion; the through hole has a radial direction Y perpendicular to the thickness direction X, and the extension segment has an eighth surface away from the through hole in the radial direction Y; The secondary battery further comprises: A second reinforcement member is disposed in the accommodating cavity and is connected to the seventh surface and the eighth surface respectively.

11. The secondary battery according to claim 1, characterized in that: The extension portion is provided with a plurality of the guide holes, and the plurality of guide holes are arranged at intervals along the circumference of the extension portion.

12. The secondary battery according to claim 9, characterized in that: The extension section includes a first connecting section and a first bending section, the first connecting section is connected to the seventh surface, the first bending section is connected to a side of the first connecting section away from the seventh surface, and a side of the first bending section away from the first connecting section is connected to the blocking portion; wherein the first reinforcement member, the first connecting section, the first bending section and the blocking portion together enclose the guide hole.

13. The secondary battery according to claim 9, characterized in that: The blocking portion includes a second connecting section, a second bending section and a third connecting section; the second connecting section is connected to an end of the extension section away from the seventh surface, the second bending section is connected to a side of the second connecting section away from the extension section, and the third connecting section is connected to a side of the second bending section away from the second connecting section; wherein, the first reinforcement member, the extension section, the second connecting section, the second bending section and the third connecting section together enclose the guide hole.

14. An electrical device, characterized in that: The secondary battery comprises the secondary battery according to any one of claims 1 to 13, wherein the secondary battery is used to supply power to the electrical device.

Images