Cover plate assembly and single cell

Abstract

This application provides a cover plate assembly and a single battery cell. The cover plate assembly includes: a cover plate, electrode terminals connected to the cover plate, and an insulating sealing assembly connected to the electrode terminals. The cover plate body includes an inner wall facing the electrode assembly. The cover plate includes a cover plate body with a mounting hole extending in a first direction. The electrode terminals include a terminal body, a fixing portion, and a terminal base plate. The terminal body is connected to the terminal base plate, and the terminal base plate is located at the end of the mounting hole near the electrode assembly. The terminal body at least partially passes through the mounting hole, and the end of the terminal body away from the electrode assembly extends out of the mounting hole. The fixing portion is located on the outer periphery of the end of the terminal body away from the electrode assembly, integrally formed with the terminal body, and extends radially along the terminal body. The insulating sealing assembly and the cover plate body are at least partially clamped between the fixing portion and the terminal base plate. The cover plate assembly and single battery cell provided by this application can reduce the height of the terminal body protruding from the outer surface of the cover plate body.

Description

Technical Field

[0001] This application relates to the field of energy storage technology, and in particular to a cover plate assembly and a single battery cell. Background Technology

[0002] The single cell includes a housing with an open end and a cover assembly that closes to the open end. The cover assembly and the housing can be closed to form a receiving space for accommodating the electrode assembly.

[0003] The cover plate assembly includes a cover plate body directly connected to the housing, and electrode terminals (including positive and negative terminals) installed on the cover plate body. One end of the electrode terminal can be electrically connected to the electrode assembly, and the other end extends out of the cover plate body and is exposed for connection to an external circuit.

[0004] If the exposed portion of the electrode terminals protrudes significantly beyond the outer surface of the cover plate (e.g., up to 3mm to 3.2mm), it will result in a low energy density for the individual battery cells, failing to meet the energy density requirements for individual batteries. Utility Model Content

[0005] In view of this, the purpose of this application is to provide a cover plate assembly and a single cell to at least partially solve the problem that the exposed portion of the electrode terminals protrudes too much from the cover plate body.

[0006] Based on the above objectives, a first aspect of this application provides a cover plate assembly, comprising: a cover plate, an electrode terminal connected to the cover plate, and an insulating sealing assembly connected to the electrode terminal; the cover plate body includes an inner wall facing the electrode assembly; the cover plate includes a cover plate body, the cover plate body being provided with a mounting hole extending along a first direction, the first direction being the thickness direction of the cover plate body; the electrode terminal includes an electrode post body, a fixing part, and an electrode post base plate, the electrode post body being connected to the electrode post base plate, the electrode post base plate being located at one end of the mounting hole near the electrode assembly, the electrode post body at least partially passing through the mounting hole, and the end of the electrode post body away from the electrode assembly extending out of the mounting hole; the fixing part is located on the outer periphery of the end of the electrode post body away from the electrode assembly, integrally formed with the electrode post body, and extending radially along the electrode post body; the insulating sealing assembly and the cover plate body are at least partially clamped between the fixing part and the electrode post base plate.

[0007] Optionally, a first transition portion is formed between the surface of the fixing part near the cover plate body and the circumferential sidewall of the pole body.

[0008] Optionally, the insulating sealing assembly includes an upper insulating portion, which is at least partially located between the electrode terminal and the cover plate body and extends to the mounting hole. A second transition portion is formed at a position of the upper insulating portion corresponding to the first transition portion, and a first gap is provided between the first transition portion and the second transition portion.

[0009] Optionally, both the first transition portion and the second transition portion are non-right-angled surfaces.

[0010] Optionally, both the first transition portion and the second transition portion are arc surfaces or inclined surfaces.

[0011] Optionally, a second gap is provided between the portion of the upper insulating part extending into the mounting hole and the circumferential sidewall of the pole body.

[0012] Optionally, the upper insulating portion extends beyond the surface of the fixing portion near the electrode assembly along the first direction and covers a portion of the circumferential sidewall of the fixing portion; a third gap is provided between the upper insulating portion and the covered circumferential sidewall of the fixing portion.

[0013] Optionally, the second direction is the radial direction of the mounting hole;

[0014] When the first transition portion is an arc surface, the radius of the arc surface is R, where R ≤ 1.5 mm; when the first transition portion is an inclined surface, the dimension of the inclined surface along the second direction is C, where C ≤ 1.5 mm; and / or,

[0015] The minimum dimension of the second gap along the second direction is L2, where L2 ≥ 0.1 mm; and / or,

[0016] The minimum dimension of the third gap along the second direction is L1, where L1 ≥ 0.1 mm.

[0017] Optionally, the insulating sealing assembly includes a sealing ring and a lower insulating portion, the sealing ring being at least partially located between the electrode terminal and the cover plate body, and the lower insulating portion being located on the inner wall near the electrode assembly; when the sealing ring is in a state of being squeezed by the cover plate body and the electrode terminal, the sealing ring engages with the lower insulating portion.

[0018] Based on the same inventive concept, the second aspect of this application also provides a single-cell battery, including the cover assembly as described in the first aspect.

[0019] As can be seen from the above, the cover plate assembly and single cell provided in this application, because the fixing part is integrally formed and connected to the electrode post body, can still meet the connection strength requirements between the electrode post body and the fixing part even if the height of the electrode post body protruding from the outer surface of the cover plate body is reduced, ensuring a reliable connection between the two. At the same time, when the height of the electrode post body protruding from the outer surface of the cover plate body is reduced, the space reduced in the electrode post body can be used to increase the height of the single cell casing, thereby expanding the internal space of the casing to accommodate larger electrode components and improving the energy density of the single cell. Attached Figure Description

[0020] To more clearly illustrate the technical solutions in this application or related technologies, the drawings used in the description of the embodiments or related technologies will be briefly introduced below. Obviously, the drawings described below are only embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0021] Figure 1 This is a partial cross-sectional schematic diagram of the cover plate assembly of the first structure according to an embodiment of this application;

[0022] Figure 2 This is a partial cross-sectional schematic diagram of the cover plate assembly of the second structure according to an embodiment of this application;

[0023] Figure 3 This is a cross-sectional view of an electrode terminal of one structure in a cover plate assembly of the second structure according to an embodiment of this application before assembly;

[0024] Figure 4 This is a cross-sectional view of the electrode terminal of another structure in the cover plate assembly of the second structure of this application before assembly;

[0025] Figure 5 This is a partial cross-sectional schematic diagram of the cover plate assembly of the third structure according to an embodiment of this application.

[0026] Explanation of reference numerals in the attached figures:

[0027] 100. Cover plate; 110. Cover plate body; 111. Inner wall; 120. Mounting hole;

[0028] 200, Insulating and sealing assembly; 210, Upper insulating part; 211, Second transition part; 220, Sealing ring; 230, Lower insulating part;

[0029] 300, Electrode terminal; 310, Electrode post body; 320, Fixing part; 330, Electrode post base plate; 340, First transition part; 350, Annular protrusion; 360, Annular connector;

[0030] 400, Electrode assembly; 500, First gap; 600, Second gap; 700, Third gap; 800, Upper insulating component; 900, Lower insulating component; 1000, Sealing gap. Detailed Implementation

[0031] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with specific embodiments and the accompanying drawings.

[0032] It should be noted that, unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components described in these embodiments do not limit the scope of this application.

[0033] At the same time, it should be understood that, for ease of description, the dimensions of the various parts shown in the accompanying drawings are not drawn according to actual scale.

[0034] The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the scope of this application and its application or use.

[0035] It should be noted that, unless otherwise defined, the technical or scientific terms used in the embodiments of this application should have the ordinary meaning understood by one of ordinary skill in the art to which this application pertains. The terms "first," "second," and similar terms used in the embodiments of this application do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Terms such as "comprising" or "including" mean that the element or object preceding the word encompasses the elements or objects listed after the word and their equivalents, without excluding other elements or objects. Terms such as "connected" or "linked" are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. Terms such as "upper," "lower," "left," and "right" are only used to indicate relative positional relationships; when the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0036] Figure 1 A partial cross-sectional schematic diagram of the cover plate assembly of the first structure is shown.

[0037] like Figure 1 In some embodiments, the cover assembly includes a cover 100, which includes a cover body 110. The cover body 110 is provided with a portion along its thickness direction (e.g., ...). Figure 1A mounting hole 120 (hereinafter referred to as the first direction) is provided through the Z direction, and one side surface of the cover plate body 110 along the first direction faces the electrode assembly 400. The electrode terminal 300 includes a pole body 310, which at least partially penetrates the mounting hole 120. The bottom end of the pole body 310 near the electrode assembly 400 is used for electrical connection with the electrode assembly 400 (for example, the pole body 310 can be soldered to an adapter or to a tab of the electrode assembly 400), and the top end of the pole body 310 away from the electrode assembly 400 is used for electrical connection with an external circuit.

[0038] In order to axially limit the columnar electrode body 310, an electrode base plate 330 is connected to one end of the electrode body 310 near the electrode assembly 400, and an annular connector 340 is provided at the other end near the electrode body 310, which is fitted onto the electrode body 310. The cover plate 100 is located between the electrode base plate 330 and the annular connector 340 along the first direction.

[0039] Both the annular connector 340 and the cover plate body 110 are metal structural components, and both have good electrical conductivity. Since the electrode terminal 300 needs to be electrically connected to the electrode assembly 400, in order to avoid a short circuit due to contact between the electrode terminal 300 and the cover plate body 110, it is necessary to ensure good insulation performance between the annular connector 340 and the cover plate body 110.

[0040] Therefore, an upper insulating member 800 can be provided between the annular connector 340 and the cover plate 100. The upper insulating member 800 is an annular structure fitted onto the electrode body 310. The circumferential inner wall of the upper insulating member 800 is close to the circumferential side wall of the electrode body 310. The bottom surface of the upper insulating member 800 abuts against the surface of the cover plate body 110 away from the electrode assembly 400, and the top surface abuts against the annular connector 340, so as to isolate the annular connector 340 and the cover plate body 110 through the upper insulating member 800.

[0041] Understandably, to ensure the stable and reliable insulation performance of the upper insulating component 800, the relative positions of the upper insulating component 800, the electrode terminal 300, and the cover plate 100 need to be kept fixed. To fix the upper insulating component 800, an electrode base plate 330 can be connected to the end of the electrode post body 310 near the electrode assembly 400. The upper insulating component 800 and the cover plate 100 are located between the electrode base plate 330 and the annular connector 360. The annular connector 360 and the electrode base plate 330 cooperate to press the upper insulating component 800 and the cover plate 100 together, thereby keeping the relative positions of the upper insulating component 800, the electrode terminal 300, and the cover plate 100 fixed.

[0042] However, the applicant discovered that in order for the annular connector 360 to provide a large and reliable downward pressure force on the upper insulator 800, it is necessary to ensure a large connection strength between the annular connector 360 and the electrode body 310. If the annular connector 360 and the electrode body 310 are independent of each other, then a large effective connection area is required between the annular connector 360 and the electrode body 310. Since the diameter of the electrode body 310 is fixed, in order to increase the effective connection area between the electrode body 310 and the annular connector 360, the thickness of the annular connector 360 and the height of the electrode body 310 can only be increased along the first direction. This causes the top of the electrode body 310 to protrude a considerable distance from the outer surface of the cover body 110 (i.e., the surface of the cover body 110 away from the electrode assembly 400).

[0043] Furthermore, since the pole body 310 needs to be connected to an external circuit, it is necessary to ensure that the top of the annular connector 360 does not extend beyond the top of the pole body 310. Otherwise, when connecting to an external circuit, the annular connector 360 will interfere with the external circuit (e.g., a bar).

[0044] When the annular connector 360 and the pole body 310 are independent of each other, under the existing processing technology, they not only have their own dimensional tolerances, but also have assembly position tolerances during assembly. In order to ensure that the annular connector 360 is not higher than the pole body 310, considering the above tolerances, a certain height margin needs to be added to the pole body 310 when designing it. This further increases the height of the pole body 310 beyond the outer surface of the cover plate body 110 (hereinafter referred to as the exposed height of the pole body 310).

[0045] To reduce the exposed height of the pole body 310, the connection method between the pole body 310 and the annular connector 360 can be changed.

[0046] Figure 2 A partial cross-sectional schematic diagram of the cover plate assembly with the second structure is shown.

[0047] like Figure 2In some embodiments, the cover plate assembly includes: a cover plate 100, an electrode terminal 300 connected to the cover plate 100, and an insulating sealing assembly 200 connected to the electrode terminal 300; the cover plate body 110 includes an inner wall 111 facing the electrode assembly 400; the cover plate 100 includes a cover plate body 110, the cover plate body 110 being provided with a mounting hole 120 extending along a first direction, the first direction being the thickness direction of the cover plate body 110; the electrode terminal 300 includes an electrode post body 310, a fixing part 320, and an electrode post base plate 330, the electrode post body 310... The electrode post 310 is connected to the base plate 330, which is located at the end of the mounting hole 120 near the electrode assembly 400. The electrode post body 310 is at least partially inserted through the mounting hole 120, and the end of the electrode post body 310 away from the electrode assembly 400 extends out of the mounting hole 120. The fixing part 320 is located on the outer periphery of the end of the electrode post body 310 away from the electrode assembly 400, is integrally formed with the electrode post body 310, and extends radially along the electrode post body 310. The insulating sealing assembly 200 and the cover plate body 110 are at least partially clamped between the fixing part 320 and the base plate 330.

[0048] For example, the insulating sealing assembly 200 may include structural components for sealing the cover plate 100 and the electrode terminal 300 together and / or structural components for insulating the cover plate 100 and the electrode terminal 300 together.

[0049] For example, the radial section of the mounting hole 120 can be circular or polygonal.

[0050] For example, the pole body 310 can be a cylinder with a circular radial cross-section, or it can be a cylinder with a polygonal radial cross-section. It should be noted that the diameter of the pole body 310 can refer to the diameter of the circular cross-section, or it can refer to the diameter of the circumcircle of the polygonal cross-section.

[0051] For example, the outer contour shape of the radial section of the fixing part 320 may be the same as or different from the outer contour shape of the radial section of the pole body 310.

[0052] For example, the fixing part 320 can be continuously or intermittently arranged around the circumferential sidewall of the electrode body 310. When the fixing part 320 is continuously arranged, a more uniform downward pressure force can be provided to the upper insulating part 210 to ensure the stability of the cover plate assembly structure. When the fixing part 320 is intermittently arranged, the material cost of the electrode terminal 300 can be reduced.

[0053] For example, Figure 3 A cross-sectional view of an electrode terminal 300 before assembly is shown. Figure 3Before assembly, an annular protrusion 350 can be formed on the top edge of the electrode body 310, at which time the electrode base plate 330 can be fixedly connected to the electrode body 310. When assembling the cover plate assembly, the insulating sealing assembly 200 can be connected to the electrode terminal 300 first, and then the annular protrusion 350 can be moved radially (e.g., towards the electrode body 310) towards the electrode body 310. Figure 3 (in the X direction) bend until it engages with the pole base plate 330 to clamp the cover plate body 110 and the insulating sealing assembly 200. At this time, the bent annular protrusion 35 forms a fixing part 320.

[0054] For example, Figure 4 A cross-sectional view of an electrode terminal 300 with another structure before assembly is shown. (See diagram.) Figure 4 Before assembly, a fixing portion 320 extending radially along the electrode body 310 is formed on the electrode body 310 (the fixing portion 320 can be formed by the aforementioned bent annular protrusion 350, or by cutting or other processes). At this time, the electrode body 310 is not connected to the electrode base plate 330. When assembling the cover plate assembly, the insulating sealing assembly 200 can be connected to the electrode terminal 300 first, and then the electrode base plate 330 can be connected (e.g., welded) to the bottom of the electrode body 310.

[0055] It should be noted that the inner wall 111 is the surface of the cover plate body 110 that is arranged along the first direction and faces the electrode assembly 400.

[0056] Compared to the case where the fixing part 320 and the pole body 310 are independent and connected by welding or riveting, in this embodiment, the fixing part 320 and the pole body 310 are integrally formed and connected, thereby enabling a higher connection strength between the two. Therefore, while ensuring a reliable connection between the fixing part 320 and the pole body 310, the thickness (dimension along the first direction) of the fixing part 320 can be designed to be smaller. Correspondingly, the exposed height of the pole body 310 can also be designed to be smaller.

[0057] Meanwhile, when the pole body 310 and the fixing part 320 are integrally formed and connected, there is no longer an assembly position tolerance between them. When designing the pole body 310, it is not necessary to design a height allowance for the assembly position tolerance, which helps to reduce the exposed height of the pole body 310. Furthermore, in this embodiment, the relative position between the top end of the fixing part 320 and the top end of the pole body 310 along the first direction is relatively easy to control. Therefore, the top end of the pole body 310 can be flush with the top end of the fixing part 320, thereby further reducing the exposed height of the pole body 310.

[0058] The cover plate assembly provided in this embodiment, because the fixing part 320 and the electrode body 310 are integrally formed and connected, can meet the connection strength requirements even if the area at the connection point is small. Therefore, the thickness of the fixing part 320 and the exposed height of the electrode body 310 can be reduced. At the same time, because the fixing part 320 and the electrode body 310 are integrally formed and connected, the relative positional accuracy between the two is high, providing a structural basis for the top of the fixing part 320 to be flush with the top of the electrode body 310. It is no longer necessary for the electrode body 310 to protrude from the fixing part 320 along the first direction, thereby helping to further reduce the exposed height of the electrode body 310 and improve the energy density of the single battery using the cover plate assembly of this embodiment.

[0059] like Figure 2 In some embodiments, a first transition portion 340 is formed between the surface of the fixing portion 320 near the cover plate body 110 (hereinafter referred to as the bottom surface of the fixing portion 320) and the circumferential sidewall of the pole body 310.

[0060] For example, if the fixing part 320 is formed by bending the annular protrusion 350 as described above, the first transition part 340 can be formed by material extrusion when bending the annular protrusion 350.

[0061] A first transition portion 340 is formed between the fixing portion 320 and the pole body 310, which can prevent stress concentration at the connection between the fixing portion 320 and the pole body 310, help improve the connection strength between the two, and ensure that the fixing portion 320 and the pole base plate 330 can provide a stable and reliable clamping force for the cover plate body 110 and the insulating sealing assembly 200.

[0062] like Figure 2 In some embodiments, the insulating sealing assembly 200 includes an upper insulating portion 210, which is at least partially located between the electrode terminal 300 and the cover plate body 110 and extends to the mounting hole 120. A second transition portion 211 is formed at a position of the upper insulating portion 210 corresponding to the first transition portion 340, and a first gap 500 is provided between the first transition portion 340 and the second transition portion 211.

[0063] Normally, the hardness of the upper insulating part 210 is less than that of the electrode terminal 300. If the upper insulating part 210 interferes with the electrode terminal 300, the upper insulating part 210 may crack under pressure, thereby adversely affecting the insulation performance between the electrode terminal 300 and the cover plate 100.

[0064] In this embodiment, a second transition portion 211 is provided in the upper insulating portion 210, thereby forming a first gap 500 between the second transition portion 211 and the first transition portion 340. During the assembly of the cover plate assembly, contact between the second transition portion 211 and the first transition portion 340 can be prevented, avoiding interference between the upper insulating portion 210 and the electrode terminal 300, ensuring the structural integrity of the upper insulating portion 210, and thus ensuring good insulation performance between the electrode terminal 300 and the cover plate 100.

[0065] like Figure 2 In some embodiments, both the first transition portion 340 and the second transition portion 211 are non-right-angled surfaces.

[0066] For example, a non-right-angled surface can be an irregular arc surface, a circular arc surface, or an inclined surface.

[0067] For example, non-right-angled surfaces can be formed by machining (e.g., cutting), by extruding material, or by injection molding.

[0068] For the first transition section 340, when the connection position between the bottom surface of the fixing section 320 and the circumferential side wall of the pole body 310 is a non-right angle surface, more material will accumulate compared to a right angle surface. This material helps to further improve the connection strength between the fixing section 320 and the pole body 310.

[0069] For the second transition portion 211, the surface of the upper insulating portion 210 that contacts the bottom surface of the fixing portion 320 is called the inner top surface of the upper insulating portion 210, and the surface of the upper insulating portion 210 that is close to the circumferential sidewall of the pole body 310 is called the circumferential inner wall of the upper insulating portion 210. When the connection position between the inner top surface and the circumferential inner wall of the upper insulating portion 210 is a non-right angle surface, a portion of the material will be missing compared to a right angle surface. This helps to move the surface of the second transition portion 211 away from the surface of the first transition portion 340, thereby forming a first gap 500 between the two, ensuring that there is no interference or compression between them.

[0070] like Figure 2 In some embodiments, both the first transition portion 340 and the second transition portion 211 are arc surfaces.

[0071] When both the first transition portion 340 and the second transition portion 211 are arc surfaces, the arc surfaces themselves, as well as the positions where they connect with adjacent surfaces, do not form sharp corners. Therefore, their ability to disperse stress is stronger, which can further reduce the risk of deformation or breakage due to stress concentration. At the same time, when assembling the cover plate assembly, the arc surfaces can prevent them from scratching the surfaces of other parts that come into contact with them, which helps to improve the yield rate and facilitates mass production.

[0072] Figure 5A partial cross-sectional schematic diagram of the cover plate assembly with the third structure is shown.

[0073] like Figure 5 In some embodiments, both the first transition portion 340 and the second transition portion 211 are inclined surfaces.

[0074] Understandably, inclined surfaces are easier to process and shape. If both the first transition part 340 and the second transition part 211 are inclined surfaces, it will help reduce the forming difficulty and processing cost of both, which is conducive to mass production.

[0075] Meanwhile, the guiding effect of the bevel is more obvious. When assembling the cover plate assembly, the bevel can be used to assist in positioning or insertion alignment, which helps to improve assembly efficiency.

[0076] like Figure 2 In some embodiments, a second gap 600 is provided between the portion of the upper insulating portion 210 extending into the mounting hole 120 and the circumferential sidewall of the pole body 310.

[0077] When the electrode terminal 300 is charged, discharged or soldered, the electrode body 310 will expand due to heat. If the portion of the upper insulating part 210 extending into the mounting hole 120 is in contact with the circumferential sidewall of the electrode body 310, then when the electrode body 310 expands due to heat, it will cause the electrode body 310 to squeeze the upper insulating part 210.

[0078] As can be seen from the foregoing, if the electrode body 310 compresses the upper insulating portion 210, it may cause the upper insulating portion 210 to crack and fail. To avoid this problem, in this embodiment, a second gap 600 is provided between the circumferential sidewall of the electrode body 310 and the portion of the upper insulating portion 210 extending into the mounting hole 120. When the electrode body 310 expands due to heat, the second gap 600 can accommodate the expanded portion of the electrode body 310, preventing the electrode body 310 from compressing the upper insulating portion 210, ensuring the structural integrity of the upper insulating portion 210, and thus ensuring good insulation performance between the electrode terminal 300 and the cover plate 100.

[0079] like Figure 2 In some embodiments, the upper insulating portion 210 extends beyond the surface of the fixing portion 320 near the electrode assembly 400 along a first direction and covers part of the circumferential sidewall of the fixing portion 320; a third gap 700 is provided between the upper insulating portion 210 and the covered circumferential sidewall of the fixing portion 320.

[0080] The upper insulating portion 210 extends to the top surface of the fixing portion 320, which can increase the creepage distance between the fixing portion 320 and the cover plate 100, thereby improving the insulation performance between the electrode terminal 300 and the cover plate 100.

[0081] As described above, the fixing part 320 and the electrode body 310 are integrally formed and connected, and the two have good thermal conductivity. When the electrode terminal 300 is charged, discharged or welded, the fixing part 320 will also expand due to heat. If the portion of the upper insulating part 210 that extends beyond the bottom surface of the fixing part 320 is in contact with the circumferential sidewall of the fixing part 320, then when the fixing part 320 expands due to heat, it will cause the fixing part 320 to squeeze the upper insulating part 210, which will also cause the upper insulating part 210 to crack under pressure.

[0082] To avoid this problem, in this embodiment, a third gap 700 is provided between the upper insulating portion 210 and the circumferential sidewall of the covered fixing portion 320. When the fixing portion 320 expands due to heat, the third gap 700 can accommodate the expanded portion of the fixing portion 320, preventing the fixing portion 320 from squeezing the upper insulating portion 210, ensuring the structural integrity of the upper insulating portion 210, and thus ensuring good insulation performance between the electrode terminal 300 and the cover plate 100.

[0083] like Figure 2 In some embodiments, the second direction (e.g.) Figure 2 The X direction in the figure is the radial direction of the mounting hole 120; when the first transition part 340 is an arc surface, the radius of the arc surface is R, and R≤1.5mm.

[0084] For example, R can be 0.2mm, 0.4mm, 0.5mm, 0.6mm, 0.8mm, 1mm, 1.2mm, 1.4mm or 1.5mm.

[0085] For example, R > 0 mm, so as to ensure that the first transition portion 340 can play the role of improving the connection strength between the fixing portion 320 and the pole body 310.

[0086] Understandably, the area where the first transition portion 340 is located on the bottom surface of the fixing portion 320 cannot effectively compress the upper insulating portion 210; only the flat area on the bottom surface can effectively compress the upper insulating portion 210.

[0087] If R is too large, the first transition portion 340 will occupy too much of the planar area on the bottom surface of the fixing portion 320, resulting in the bottom surface of the fixing portion 320 having too small an area to effectively compress the upper insulating portion 210, making it impossible for the fixing portion 320 to provide a reliable downward pressure force to the upper insulating portion 210.

[0088] To avoid the above problems, in this embodiment, R is designed to be R≤1.5mm, which can make the bottom surface of the fixing part 320 have a larger effective pressing area against the upper insulating part 210, ensuring that the fixing part 320 can provide a reliable downward pressing force to the upper insulating part 210.

[0089] like Figure 5 In some embodiments, when the first transition portion 340 is an inclined surface, the dimension of the inclined surface along the second direction is C, where C≤1.5mm.

[0090] For example, C can be 0.2mm, 0.4mm, 0.5mm, 0.6mm, 0.8mm, 1mm, 1.2mm, 1.4mm or 1.5mm.

[0091] For example, C > 0 mm, so as to ensure that the first transition portion 340 can play the role of improving the connection strength between the fixing portion 320 and the pole body 310.

[0092] The beneficial effects of designing C to be C≤1.5mm in this embodiment are similar to those of designing R to be R≤1.5mm, and will not be repeated here.

[0093] like Figure 2 In some embodiments, the minimum dimension of the second gap 600 along the second direction is L2, where L2 ≥ 0.1 mm.

[0094] For example, L2 can be 0.1mm, 0.2mm, 0.3mm, 0.4mm, 0.5mm, 0.6mm, 0.7mm, 0.8mm, 0.9mm or 1mm.

[0095] For example, L2 ≤ 2mm. If L2 is too large, the diameter of the terminal body 310 will be too small, which will adversely affect the electrical performance, service life, and safety performance of the single battery. When L2 ≤ 2mm, the space within the mounting hole 120 is sufficient. Under the premise of ensuring that the terminal body 310 can pass through the mounting hole 120, the diameter of the terminal body 310 can be designed to be larger, thereby improving the electrical performance, service life, and safety performance of the single battery.

[0096] If L2 is too small, when the electrode body 310 expands due to heat, the electrode body 310 will still exert a large compressive force on the upper insulation part 210, causing the upper insulation part 210 to crack under pressure, thereby adversely affecting the insulation performance between the electrode terminal 300 and the cover plate 100.

[0097] To avoid the above problems, in this embodiment, L2 is designed to be L2≥0.1mm, which can prevent the electrode body 310 from squeezing the upper insulating part 210, ensure the structural integrity of the upper insulating part 210, and thus ensure good insulation performance between the electrode terminal 300 and the cover plate 100.

[0098] like Figure 2 In some embodiments, the minimum dimension of the third gap 700 along the second direction is L1, where L1 ≥ 0.1 mm.

[0099] For example, L1 can be 0.1mm, 0.2mm, 0.3mm, 0.4mm, 0.5mm, 0.6mm, 0.7mm, 0.8mm, 0.9mm or 1mm.

[0100] For example, L1 ≤ 2mm. If L1 is too large, the upper insulating part 210 will occupy too much surface space of the cover plate body 110, which is not conducive to installing other structural components on the cover plate body 110. When L1 is designed to be ≤ 2mm, each structural component can be arranged more reasonably on the cover plate body 110.

[0101] The beneficial effect of designing L1 to be ≥0.1mm is similar to the beneficial effect of designing L2 to be L2≥0.1mm, which can prevent the thermally expanded fixing part 320 from squeezing the upper insulating part 210 and avoid the upper insulating part 210 from cracking due to pressure.

[0102] like Figure 2 In some embodiments, the insulating sealing assembly 200 includes a sealing ring 220 and a lower insulating portion 230. The sealing ring 220 is at least partially located between the electrode terminal 300 and the cover plate body 110, and the lower insulating portion 230 is located on the side of the inner wall 111 near the electrode assembly 400. When the sealing ring 220 is in a state of being squeezed by the cover plate body 110 and the electrode terminal 300, the sealing ring 220 engages with the lower insulating portion 230.

[0103] by Figure 2 Taking the structure and orientation shown as an example, the cover plate body 110 and the pole base plate 330 are spaced apart along the first direction and form a sealing gap 1000 between them.

[0104] For the sealing gap 1000 on the left side of the electrode body 310, under the squeezing action of the electrode base plate 330 and the cover plate 100, both the lower insulating part 230 and the sealing ring 220 within the sealing gap 1000 can achieve a sealing effect. The lower insulating part 230 extends from the left end of the sealing gap 1000 to the right, while the sealing ring 220 extends from the right end of the sealing gap 1000 to the left. When the lower insulating part 230 and the sealing ring 220 are engaged, a complete sealing structure can be formed from the left end to the right end of the sealing gap 1000, which can further improve the sealing effect of the single cell and prevent the electrolyte inside the single cell from leaking out.

[0105] Based on the same inventive concept and in conjunction with the description of the cover plate assembly in the above embodiments, this embodiment provides a single battery cell that has the corresponding technical effects of the cover plate assembly in the above embodiments, which will not be repeated here.

[0106] A single-cell battery includes a cover assembly as described in the various embodiments above.

[0107] It should be noted that some embodiments of this application have been described above. Other embodiments are within the scope of the appended claims.

[0108] The various embodiments in this application are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other.

[0109] The description in this application is given for illustrative purposes and is not intended to be exhaustive or to limit the application to the forms disclosed. Many modifications and variations will be apparent to those skilled in the art. The embodiments were chosen and described to better illustrate the principles and practical application of this application and to enable those skilled in the art to understand this application and design various embodiments with various modifications suitable for a particular purpose.

[0110] Those skilled in the art should understand that the discussion of any of the above embodiments is merely exemplary and is not intended to imply that the scope of this application is limited to these examples; under the concept of this application, the technical features of the above embodiments or different embodiments can also be combined, the steps can be implemented in any order, and there are many other variations of different aspects of the embodiments of this application as described above, which are not provided in detail for the sake of brevity.

[0111] Although this application has been described in conjunction with specific embodiments thereof, many substitutions, modifications and variations of these embodiments will be apparent to those skilled in the art from the foregoing description.

[0112] The embodiments of this application are intended to cover all such substitutions, modifications, and variations that fall within the broad scope of this application. Therefore, any omissions, modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the embodiments of this application should be included within the protection scope of this application.

Claims

1. A cover plate assembly, characterized in that, include: A cover plate, electrode terminals connected to the cover plate, and an insulating sealing assembly connected to the electrode terminals; the cover plate body includes an inner wall facing the electrode assembly; The cover plate includes a cover plate body, and the cover plate body is provided with a mounting hole that extends along a first direction, the first direction being the thickness direction of the cover plate body. The electrode terminal includes an electrode post body, a fixing part, and an electrode post base plate. The electrode post body is connected to the electrode post base plate, and the electrode post base plate is located at the end of the mounting hole near the electrode assembly. The electrode post body is at least partially inserted through the mounting hole, and the end of the electrode post body away from the electrode assembly extends out of the mounting hole. The fixing part is located on the outer periphery of the end of the electrode post body away from the electrode assembly, is integrally formed with the electrode post body, and extends radially along the electrode post body. The insulating sealing assembly and the cover plate body are at least partially clamped between the fixing part and the electrode post base plate. A first transition portion is formed between the surface of the fixing part near the cover plate body and the circumferential sidewall of the pole body; The insulating sealing assembly includes an upper insulating portion, which is at least partially located between the electrode terminal and the cover plate body and extends to the mounting hole. A second transition portion is formed at a position of the upper insulating portion corresponding to the first transition portion, and a first gap is provided between the first transition portion and the second transition portion.

2. The cover plate assembly according to claim 1, characterized in that, Both the first transition portion and the second transition portion are non-right-angled surfaces.

3. The cover plate assembly according to claim 1, characterized in that, Both the first transition portion and the second transition portion are circular arc surfaces or inclined surfaces.

4. The cover plate assembly according to claim 1, characterized in that, A second gap is provided between the portion of the upper insulating part extending into the mounting hole and the circumferential sidewall of the pole body.

5. The cover plate assembly according to claim 4, characterized in that, The upper insulating portion extends beyond the surface of the fixing portion near the electrode assembly along the first direction and covers part of the circumferential sidewall of the fixing portion; a third gap is provided between the upper insulating portion and the covered circumferential sidewall of the fixing portion.

6. The cover plate assembly according to claim 5, characterized in that, The second direction is the radial direction of the mounting hole; When the first transition portion is an arc surface, the radius of the arc surface is R, where R ≤ 1.5 mm; when the first transition portion is an inclined surface, the dimension of the inclined surface along the second direction is C, where C ≤ 1.5 mm; and / or, The minimum dimension of the second gap along the second direction is L2, where L2 ≥ 0.1 mm; and / or, The minimum dimension of the third gap along the second direction is L1, where L1 ≥ 0.1 mm.

7. The cover plate assembly according to claim 1, characterized in that, The insulating sealing assembly includes a sealing ring and a lower insulating portion. The sealing ring is at least partially located between the electrode terminal and the cover plate body, and the lower insulating portion is located on the inner wall near the electrode assembly. When the sealing ring is compressed by the cover plate body and the electrode terminal, the sealing ring engages with the lower insulating portion.

8. A single-cell battery, characterized in that, Includes the cover plate assembly as described in any one of claims 1-7.

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