Battery cell cover plate assembly, battery cell, and battery pack

Abstract

The utility model relates to battery technical field discloses the electric core cover plate subassembly, electric core and battery package. Electric core cover plate subassembly includes: cover plate, is equipped with through -hole along Z direction, pole, including pole body and the pole base of setting in the one end of pole body, and the pole body has part to wear in the through -hole, is equipped with annular boss around pole body on the pole base, and the pole base is located in the one side of cover plate, sealing ring, the part is equipped with in the through -hole and is worn in the pole body outside, and the one end of sealing ring near pole base forms annular flange, and annular flange is located between cover plate and pole base, and the one side of annular flange towards pole base is equipped with with annular boss corresponding setting annular groove, and annular boss inserts in annular groove, makes annular flange and pole base abut. Annular boss and annular groove plug -in setting, can increase the contact area and the close -fitting of sealing ring and pole base, fill up the tiny gap that traditional plane contact can exist, improve sealing performance.

Description

Technical Field

[0001] This utility model relates to the field of battery technology, specifically to a cell cover assembly, a cell, and a battery pack. Background Technology

[0002] Currently, battery cell cover assemblies are mainly composed of components such as terminals, plastic parts, aluminum plates, and sealing rings. The sealing rings are primarily used for sealing and insulation, and their sealing performance is typically achieved by compressing them. However, when the roughness of the terminal base plate is too high, the sealing ring cannot form a uniform and tight contact surface with the terminal base plate, leading to poor sealing performance in the battery cell cover assembly. Utility Model Content

[0003] In view of this, the present invention provides a cell cover assembly, a cell, and a battery pack to solve the problem of poor sealing of the cell cover assembly caused by excessive roughness of the terminal base plate.

[0004] In a first aspect, this utility model provides a battery cell cover assembly, comprising: The cover plate has through holes along the Z direction; The pole includes a pole body and a pole base disposed at one end of the pole body. The pole base is provided with an annular rib surrounding the pole body. A portion of the pole body passes through the through hole. Along the Z direction, the pole base is located on one side of the cover plate. A sealing ring is fitted over the pole body and partially passes through the through hole. The end of the sealing ring near the pole base forms an annular flange. The annular flange is located between the cover plate and the pole base. The side of the annular flange facing the pole base has an annular groove corresponding to the annular rib. The annular rib is inserted into the annular groove so that the annular flange abuts against the pole base.

[0005] Beneficial Effects: This invention features an annular rib surrounding the electrode base and a corresponding annular groove on the annular flange of the sealing ring. The annular rib inserts into the groove, achieving a mating fit between the electrode base and the sealing ring. This interlocking structure increases the contact area and tightness of the fit, effectively filling the small gaps that may exist in traditional planar contact, significantly improving sealing performance. It more reliably prevents electrolyte leakage from the battery cell and the infiltration of external air and moisture, ensuring excellent sealing of the battery cell cover assembly. Furthermore, the interlocking design of the annular rib and groove positions the sealing ring, preventing it from shifting due to vibration or pressure changes during battery cell cover assembly or use, thus ensuring structural stability.

[0006] In one alternative embodiment, the electrode post has a riveted state and an unriveted state, and along the Z direction, the thickness of the cell cover assembly in the unriveted state is greater than the thickness of the cell cover assembly in the riveted state.

[0007] Beneficial effects: Before the terminals are riveted, ample operating space is provided for the assembly of the terminals, sealing rings, and cover plates, facilitating precise positioning of components by workers (such as ensuring accurate engagement of the annular flange of the sealing ring with the annular rib of the terminal base), reducing assembly difficulty, improving assembly efficiency, and avoiding component misalignment or damage due to limited space. After the terminals are riveted, the thickness of the cell cover plate assembly decreases accordingly. During this process, the terminals exert a uniform and stable compressive force on the sealing ring, making its fit with the terminal base and cover plate tighter. Combined with the interlocking structure of the annular rib and annular groove, a double sealing guarantee is formed, significantly enhancing the overall sealing performance, thereby effectively reducing the risk of electrolyte leakage inside the cell and providing reliable support for the stable operation of the cell.

[0008] In one optional embodiment, in the unriveted state, the height of the annular rib along the Z direction is h1, and the value of h1 is in the range of 0.1mm≤h1≤0.4mm.

[0009] Beneficial effects: This utility model controls the value of h1 within the range of 0.1mm to 0.4mm, which ensures that the annular rib has sufficient structural strength, preventing deformation or breakage due to external force contact or positioning during the early stage of assembly, and ensuring precise docking with the annular groove of the sealing ring; at the same time, in the pre-assembly stage before riveting, the rib can exert a moderate pre-pressure effect on the groove, initially improving the fit and sealing performance of the two, effectively preventing dust, moisture and other impurities from entering the battery cell, while reserving reasonable compression space for the subsequent riveting process - it will not cause excessive compression damage to the sealing ring during riveting due to the rib being too high, nor will it cause insufficient sealing pressure after riveting due to the rib being too low, ultimately ensuring the long-term sealing reliability and structural stability of the battery cell cover assembly.

[0010] In one optional embodiment, in the unriveted state, the thickness of the annular rib is d1 in a direction perpendicular to the Z direction, and the value of d1 ranges from 0 mm to 0.5 mm.

[0011] Beneficial effects: In the unriveted state, limiting the thickness d1 of the annular rib along the Z-direction perpendicular to the rib to within the range of 0mm < d1 ≤ 0.5mm ensures a precise dimensional match between the annular rib and the annular groove of the sealing ring. This prevents the rib from being too thick, which could cause it to be difficult to embed smoothly into the groove, resulting in pre-assembly jamming or groove cracking, while also preventing insufficient contact area between the rib and the groove, thus weakening the initial sealing effect. Furthermore, the thinner design reduces the rib's footprint on the overall structure of the electrode base, ensuring the structural integrity and mechanical strength of the electrode base. During subsequent riveting, the thinner rib can more easily adapt to the compression of the sealing ring, further filling the sealing gap, improving overall sealing performance, effectively avoiding the risk of electrolyte leakage, and ensuring the long-term stable operation of the battery cell.

[0012] In one optional embodiment, in the unriveted state, the groove depth of the annular groove along the Z direction is h2, and the value of h2 is in the range of 0.05mm≤h2≤0.5mm.

[0013] Beneficial effects: In the unriveted state, limiting the lower limit of the groove depth h2 along the Z direction of the annular groove to 0.05mm ensures sufficient space for the rib to be accommodated, preventing the rib from not being fully embedded due to insufficient groove depth, which would cause the sealing ring surface to bulge and affect the fit with the cover plate. Limiting the upper limit of the groove depth h2 along the Z direction of the annular groove to 0.5mm prevents the groove from being too deep, leaving too large a gap at the bottom after the rib is embedded, weakening the sealing pre-compression effect in the pre-assembly stage. It also prevents the sealing ring from becoming too thin in some areas due to excessive groove depth, which would make it prone to cracking during subsequent riveting. In addition, a reasonable groove depth design allows the rib to form a stable circumferential contact with the inner wall of the groove when unriveted, effectively preventing the intrusion of external impurities, laying a good sealing foundation for the subsequent riveting process, and ultimately ensuring the long-term sealing reliability of the battery cell cover plate assembly.

[0014] In one optional embodiment, in the riveted state, the distance between the annular rib and the annular groove wall in a direction perpendicular to the Z direction is d2, and the value of d2 is in the range of 0.05mm≤d2≤0.15mm.

[0015] Beneficial effects: In the riveting state, limiting the distance d2 between the annular rib and the annular groove wall to the range of 0.05mm≤d2≤0.15mm provides sufficient buffer space for the deformation of the electrode base and sealing ring during riveting. The external force during riveting causes adaptive compression between the two, and the minimum distance of 0.05mm avoids rigid collision between the rib and the groove wall, preventing tearing of the sealing ring or cracking of the electrode base, thus ensuring the structural integrity of the assembly. On the other hand, the maximum distance of 0.15mm strictly controls the sealing gap, effectively preventing electrolyte penetration from the gap, while also preventing the rib from losing contact support with the groove wall due to excessive spacing, ensuring the stability of the sealing structure. Furthermore, a reasonable distance range can accommodate minor errors in the parts processing (such as tolerances for rib thickness and groove width), reducing assembly difficulty, improving production yield, and providing strong support for the long-term reliable operation and large-scale production of the cell cover assembly.

[0016] In one optional embodiment, in the riveted state, the compression height of the annular rib along the Z direction is h3, and the value of h3 is in the range of 0.1mm≤h3≤0.3mm.

[0017] Beneficial effects: In the riveted state, limiting the compression height h3 of the annular rib along the Z direction to within the range of 0.1mm ≤ h3 ≤ 0.3mm ensures that the rib exerts a moderate and stable pre-tightening pressure on the sealing ring. Specifically, the minimum compression of 0.1mm prevents insufficient compression from causing the rib to loosen its fit with the annular groove, thus preventing electrolyte leakage. The maximum compression of 0.3mm prevents the rib from excessively compressing the sealing ring, which could lead to permanent deformation or aging cracking due to excessive long-term stress, extending the service life of the sealing structure. Simultaneously, a reasonable compression height can be adapted to the elastic characteristics of sealing rings made of different materials (such as fluororubber and silicone), ensuring that after riveting, the elastic rebound of the rib maintains continuous sealing force without damaging the assembly structure of the electrode base and the cover plate, ultimately guaranteeing the long-term sealing reliability and structural stability of the cell cover assembly.

[0018] In one alternative embodiment, the cross-sectional shape of the annular rib is square or circular along the Z direction.

[0019] Beneficial effects: For square cross-sections, their flat top and bottom surfaces and sides can form a larger contact area with the inner wall of the annular groove. After riveting, the sealing pressure can be transmitted more evenly through surface contact, reducing local stress concentration and improving sealing reliability. At the same time, the processing technology of square cross-sections is relatively simple, and it is easy to form them by conventional methods such as milling and stamping, reducing production difficulty and cost. For circular cross-sections, their curved surface has better deformation adaptability. During the riveting and extrusion process, they can fit more smoothly with the inner wall of the groove, avoiding local damage to the sealing ring due to sharp corner contact. At the same time, circular cross-sections have no stress concentration points, and are less prone to fatigue cracks during long-term use, thus extending the service life of the ribs.

[0020] Secondly, this utility model also provides a battery cell, comprising: The housing has a cavity and an opening communicating with the cavity; The electrode assembly is disposed within the cavity and has an electrode tab at one end; The aforementioned cell cover assembly covers and seals the opening, and the electrode base is welded to the electrode tab on the side away from the cover.

[0021] Beneficial effects: The battery cell of this utility model includes the battery cell cover assembly as described above, and has all the beneficial technical effects of the battery cell cover assembly, which will not be repeated here.

[0022] Thirdly, this utility model also provides a battery pack, comprising: a plurality of the above-mentioned battery cells.

[0023] Beneficial effects: The battery pack of this utility model includes the battery cell as described above, and has all the beneficial technical effects of the battery cell, which will not be repeated here. Attached Figure Description

[0024] To more clearly illustrate the specific embodiments of this utility model or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0025] Figure 1 This is a schematic diagram of the structure of a battery cell cover assembly according to an embodiment of the present utility model; Figure 2 This is a cross-sectional schematic diagram of a battery cell cover assembly according to an embodiment of the present utility model; Figure 3 This is a schematic diagram of the structure of a pole post according to an embodiment of the present utility model; Figure 4 for Figure 3 Top view of the pole shown; Figure 5 for Figure 3 A schematic diagram of the pole structure shown from another perspective; Figure 6 This is a schematic diagram of the structure of a sealing ring according to an embodiment of the present utility model; Figure 7 This is a schematic diagram of the structure of a sealing ring according to an embodiment of the present invention from another perspective.

[0026] Explanation of reference numerals in the attached figures: 1. Cover plate; 2. Pole post; 201. Pole post body; 202. Pole post base; 2021. Annular rib; 3. Sealing ring; 301. Annular flange; 302. Annular groove. Detailed Implementation

[0027] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0028] To address the problem of poor sealing in the cell cover assembly caused by excessive roughness of the electrode base plate, this utility model provides a cell cover assembly, a cell, and a battery pack.

[0029] The following is combined Figures 1 to 7 This describes embodiments of the present invention. For ease of description below, as follows... Figure 3 As shown, a spatial rectangular coordinate system is established: the height direction of the pole post 2 (i.e. the thickness direction of the cell cover assembly) is denoted as the Z direction, the length direction of the pole post 2 (i.e. the length direction of the cell cover assembly) is denoted as the Y direction, and the width direction of the pole post 2 (i.e. the width direction of the cell cover assembly) is denoted as the X direction.

[0030] According to embodiments of the present invention, on the one hand, such as Figures 1 to 7 As shown, a battery cell cover assembly is provided, including: a cover plate 1, an electrode post 2, and a sealing ring 3.

[0031] Specifically, the cover plate 1 has a through hole along the Z direction; the pole post 2 includes a pole post body 201 and a pole post base 202 disposed at one end of the pole post body 201. The pole post base 202 is provided with an annular rib 2021 surrounding the pole post body 201. A portion of the pole post body 201 passes through the through hole. Along the Z direction, the pole post base 202 is located on one side of the cover plate 1; the sealing ring 3 is sleeved on the outside of the pole post body 201 and partially passes through the through hole. The end of the sealing ring 3 near the pole post base 202 forms an annular flange 301. The annular flange 301 is located between the cover plate 1 and the pole post base 202. The side of the annular flange 301 facing the pole post base 202 is provided with an annular groove 302 corresponding to the annular rib 2021. The annular rib 2021 is inserted into the annular groove 302, so that the annular flange 301 abuts against the pole post base 202.

[0032] This embodiment of the invention features an annular rib 2021 surrounding the electrode body 201 on the electrode base 202, and a corresponding annular groove 302 on the annular flange 301 of the sealing ring 3. The annular rib 2021 inserts into the annular groove 302, achieving abutment between the electrode base 202 and the sealing ring 3. This concave-convex interlocking structure increases the contact area and tightness of the fit, effectively filling the small gaps that may exist in traditional planar contact, significantly improving sealing performance. It more reliably prevents electrolyte leakage from the battery cell and the infiltration of external air and moisture, ensuring good sealing performance of the battery cell cover assembly. Furthermore, the interlocking design of the annular rib 2021 and the annular groove 302 positions the sealing ring 3, preventing it from shifting due to vibration or pressure changes during battery cell cover assembly or battery cell use, thus ensuring structural stability.

[0033] According to one embodiment of this utility model, the annular rib 2021 and the pole base 202 are integrally formed. This reduces manufacturing difficulty and improves the connection strength between the two.

[0034] According to one embodiment of the present invention, the electrode post 2 has a riveted state and an unriveted state. Along the Z direction, the thickness of the cell cover assembly in the unriveted state is greater than the thickness of the cell cover assembly in the riveted state. It is understandable that when the pole post 2 is not riveted, it provides sufficient operating space for the assembly of the pole post 2, sealing ring 3 and cover plate 1, making it easier for workers to accurately position each component (such as ensuring that the annular flange 301 of the sealing ring 3 and the annular rib 2021 of the pole post base 202 are accurately fitted), reducing assembly difficulty, improving assembly efficiency, and avoiding component misalignment or damage due to limited space. After the pole post 2 is riveted, the thickness of the cell cover plate assembly decreases accordingly. During this process, the pole post 2 will generate a uniform and stable compressive force on the sealing ring 3, making its fit with the pole post base 202 and cover plate 1 tighter. At the same time, combined with the previous concave-convex fitting structure of the annular rib 2021 and the annular groove 302, a double sealing guarantee can be formed, which greatly enhances the overall sealing performance, thereby effectively reducing the risk of electrolyte leakage inside the cell and providing reliable support for the stable operation of the cell.

[0035] According to one embodiment of the present invention, such as Figure 5 As shown, in the unriveted state, the height of the annular rib 2021 along the Z direction is h1, and the value of h1 ranges from 0.1mm to 0.4mm. This embodiment of the invention controls the value of h1 within the range of 0.1mm to 0.4mm. This ensures that the annular rib 2021 has sufficient structural strength, preventing deformation or breakage due to external force contact or positioning during the early stages of assembly, and guaranteeing precise alignment with the annular groove 302 of the sealing ring 3. Furthermore, in the pre-assembly stage before riveting, the rib creates a moderate pre-pressure effect on the groove, initially improving the sealing performance of both, effectively preventing dust, moisture, and other impurities from entering the battery cell. Simultaneously, it provides reasonable compression space for the subsequent riveting process—avoiding excessive compression damage to the sealing ring 3 during riveting due to an excessively high rib, and preventing insufficient sealing pressure after riveting due to an excessively low rib, ultimately ensuring the long-term sealing reliability and structural stability of the battery cell cover assembly.

[0036] It is understood that the value of h1 can be, but is not limited to, 0.1mm, 0.15mm, 0.2mm, 0.25mm, 0.3mm, 0.35mm, 0.4mm or any value between the two.

[0037] According to one embodiment of the present invention, such as Figure 4As shown, in the unriveted state, the thickness of the annular rib 2021 along the direction perpendicular to the Z direction is d1, and the value of d1 is in the range of 0mm < d1 ≤ 0.5mm. In the unriveted state, the thickness d1 of the annular rib 2021 along the Z-direction is limited to the range of 0mm < d1 ≤ 0.5mm. On the one hand, this thickness range ensures that the annular rib 2021 and the annular groove 302 of the sealing ring 3 form a precise dimensional match—neither too thick, causing the rib to be difficult to fit smoothly into the groove, resulting in pre-assembly jamming or groove cracking, nor too thin, resulting in insufficient contact area between the rib and the groove, weakening the initial sealing effect. On the other hand, the thinner thickness design reduces the rib's occupation of the overall structure of the pole base 202, ensuring the structural integrity and mechanical strength of the pole base 202. At the same time, during the subsequent riveting process, the thinner rib can more easily adapt to the compression of the sealing ring 3, further filling the sealing gap, improving the overall sealing performance, effectively avoiding the risk of electrolyte leakage, and providing a guarantee for the long-term stable operation of the battery cell.

[0038] It is understood that the value of d1 can be, but is not limited to, 0.1mm, 0.15mm, 0.2mm, 0.25mm, 0.3mm, 0.35mm, 0.4mm, 0.45mm, 0.5mm, or any value between the two.

[0039] According to one embodiment of the present invention, such as Figure 6 As shown, in the unriveted state, the groove depth of the annular groove 302 along the Z direction is h2, and the value of h2 ranges from 0.05mm ≤ h2 ≤ 0.5mm. Limiting the lower limit of the groove depth h2 along the Z direction of the annular groove 302 to 0.05mm in the unriveted state ensures sufficient space for the protruding rib, preventing it from being unable to fully embed due to a shallow groove, which would cause the sealing ring 3 to bulge and affect its fit with the cover plate 1. Limiting the upper limit of the groove depth h2 along the Z direction of the annular groove 302 to 0.5mm prevents the groove from being too deep, leaving an excessive gap at the bottom after the protruding rib is embedded, weakening the sealing pre-pressure effect during pre-assembly. It also prevents the sealing ring 3 from becoming too thin locally due to an excessively deep groove, which could easily lead to cracking during subsequent riveting. Furthermore, a reasonable groove depth design allows the protruding rib to form a stable circumferential contact with the inner wall of the groove when unriveted, effectively preventing the intrusion of external impurities and laying a good sealing foundation for subsequent riveting processes, ultimately ensuring the long-term sealing reliability of the battery cell cover assembly.

[0040] It is understood that the value of h2 can be, but is not limited to, 0.05mm, 0.1mm, 0.15mm, 0.2mm, 0.25mm, 0.3mm, 0.35mm, 0.4mm, 0.45mm, 0.5mm, or any value between the two.

[0041] According to one embodiment of the present invention, such as Figure 2 As shown, in the riveting state, the distance between the annular rib 2021 and the groove wall of the annular groove 302 along the direction perpendicular to the Z direction is d2, and the value of d2 is in the range of 0.05mm≤d2≤0.15mm. Limiting the distance d2 between the annular rib 2021 and the groove wall of the annular groove 302 to the range of 0.05mm≤d2≤0.15mm in the riveting state serves two purposes. Firstly, this distance provides sufficient buffer space for the deformation of the pole base 202 and the sealing ring 3 during riveting—the external force during riveting will cause adaptive compression between the two. The minimum distance of 0.05mm can prevent the sealing ring 3 from tearing or the pole base 202 from cracking due to rigid collision between the rib and the groove wall, ensuring the structural integrity of the component. Secondly, the maximum distance of 0.15mm can strictly control the sealing gap, effectively preventing electrolyte from seeping through the gap, while also preventing the rib from losing contact support with the groove wall due to excessive distance, ensuring the stability of the sealing structure. In addition, a reasonable spacing range can accommodate minor errors in the parts processing (such as tolerances for rib thickness and groove width), reduce assembly difficulty, improve production qualification rate, and provide strong support for the long-term reliable operation and large-scale production of battery cell cover plate assemblies.

[0042] It is understood that the value of d2 can be, but is not limited to, 0.05mm, 0.06mm, 0.07mm, 0.08mm, 0.09mm, 0.1mm, 0.12mm, 0.15mm, or any value between the two.

[0043] It should be noted that in this embodiment of the utility model, the Z direction is the thickness direction of the cell cover assembly, and the direction perpendicular to the Z direction is the length direction (Y direction) and width direction (X direction) of the cell cover assembly.

[0044] According to one embodiment of the present invention, such as Figure 2As shown, in the riveted state, the compression height of the annular rib 2021 along the Z direction is h3, and the value of h3 ranges from 0.1mm ≤ h3 ≤ 0.3mm. Limiting the compression height h3 of the annular rib 2021 along the Z direction to the range of 0.1mm ≤ h3 ≤ 0.3mm in the riveted state ensures that the rib forms a moderate and stable pre-tightening pressure on the sealing ring 3. Specifically, the minimum compression of 0.1mm avoids insufficient compression causing the rib to loosen its fit with the annular groove 302, thus preventing effective sealing and electrolyte leakage; while the maximum compression of 0.3mm avoids excessive compression of the sealing ring 3 by the rib, preventing permanent deformation or aging cracking of the sealing ring 3 due to excessive long-term stress, thereby extending the service life of the sealing structure. Meanwhile, the reasonable compression height can be adapted to the elastic characteristics of sealing rings 3 made of different materials (such as fluororubber and silicone), ensuring that after riveting, the continuous sealing force can be maintained through the elastic rebound of the ribs, without damaging the assembly structure of the pole base 202 and the cover plate 1, ultimately ensuring the long-term sealing reliability and structural stability of the battery cell cover plate assembly.

[0045] It is understood that the value of h3 can be, but is not limited to, 0.1mm, 0.15mm, 0.2mm, 0.25mm, 0.3mm or any value between the two.

[0046] According to one embodiment of the present invention, such as Figure 3 and Figure 4 As shown, along the Z-direction, the cross-sectional shape of the annular rib 2021 is either square or circular. It can be understood that for a square cross-section, its flat upper and lower end faces and sides can form a larger contact area with the inner wall of the annular groove 302. After riveting, more uniform sealing pressure can be transmitted through surface contact, reducing local stress concentration and improving sealing reliability. Simultaneously, the processing technology of a square cross-section is relatively simple, facilitating forming through conventional methods such as milling and stamping, reducing production difficulty and cost. For a circular cross-section, its curved surface has better deformation adaptability, allowing for smoother contact with the inner wall of the groove during riveting and extrusion, avoiding localized damage to the sealing ring 3 due to sharp corner contact. Furthermore, the circular cross-section has no stress concentration points, making it less prone to fatigue cracks during long-term use, thus extending the service life of the rib.

[0047] According to an embodiment of the present invention, another aspect provides a battery cell, including: a housing, an electrode assembly, and the aforementioned battery cell cover plate assembly.

[0048] Specifically, the housing has a cavity and an opening connected to the cavity; the electrode assembly is located in the cavity and has an electrode tab at one end; the aforementioned cell cover plate assembly covers and seals the opening, and the electrode base 202 is welded to the electrode tab on the side away from the cover plate 1.

[0049] The battery cell of this utility model embodiment includes the battery cell cover assembly as described above, and has all the beneficial technical effects of the battery cell cover assembly, which will not be repeated here.

[0050] In one embodiment, the electrode assembly includes a plurality of alternately arranged positive and negative electrode plates and a separator disposed between the positive and negative electrode plates. Specifically, the positive electrode plate includes a positive current collector and a positive active material disposed on at least one surface of the positive current collector. As an example, the positive current collector has two surfaces opposite each other in its own thickness direction, and the positive active material is disposed on either or both of the opposite surfaces of the positive current collector. As an example, the positive current collector can be a metal foil, a foamed metal, or a composite current collector. For example, as a metal foil, silver-surfaced aluminum or stainless steel, copper, aluminum, nickel, carbon electrode, carbon, nickel, or titanium, etc., can be used. The foamed metal can be foamed nickel, foamed copper, foamed aluminum, foamed alloy, or foamed carbon, etc. The composite current collector may include a polymer material base layer and a metal layer. Composite current collectors can be formed by forming metallic materials (aluminum, aluminum alloys, nickel, nickel alloys, titanium, titanium alloys, silver, and silver alloys, etc.) on a polymer substrate (such as polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polyethylene, etc.). As an example, the positive electrode active material may include at least one of the following: lithium phosphates, lithium transition metal oxides, and their respective modified compounds. However, this invention is not limited to these materials, and other conventional materials that can be used as positive electrode active materials for battery cells may also be used. These positive electrode active materials may be used alone or in combination of two or more. Examples of lithium phosphates include, but are not limited to, lithium iron phosphate (such as LiFePO4 (also abbreviated as LFP)), lithium iron phosphate and carbon composites, lithium manganese phosphate (such as LiMnPO4), lithium manganese phosphate and carbon composites, lithium iron manganese phosphate, and lithium iron manganese phosphate and carbon composites, at least one of these.

[0051] In some embodiments, the negative electrode sheet may include a negative electrode current collector and a negative electrode active material disposed on at least one surface of the negative electrode current collector. As an example, the negative electrode current collector has two surfaces opposite each other in its own thickness direction, and the negative electrode active material is disposed on either or both of the opposite surfaces of the negative electrode current collector. As an example, the negative electrode current collector may be a metal foil, foamed metal, or a composite current collector. For example, as a metal foil, silver-treated aluminum or stainless steel, copper, aluminum, nickel, carbon electrodes, carbon, nickel, or titanium, etc., may be used. The composite current collector may include a polymeric material substrate and a metal layer. The foamed metal may be foamed nickel, foamed copper, foamed aluminum, foamed alloy, or foamed carbon, etc. The composite current collector can be formed by forming a metal material (copper, copper alloy, nickel, nickel alloy, titanium, titanium alloy, silver, and silver alloy, etc.) on a polymeric material substrate (such as a substrate of polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polyethylene, etc.). As an example, the negative electrode active material may be a negative electrode active material known in the art for use in battery cells. As an example, the negative electrode active material may include at least one of the following materials: artificial graphite, natural graphite, soft carbon, hard carbon, silicon-based materials, tin-based materials, and lithium titanate, etc.

[0052] In some embodiments, the separator is a separator membrane. This invention does not impose any particular limitation on the type of separator membrane; any known porous separator membrane with good chemical and mechanical stability can be selected. As an example, the main material of the separator membrane can be selected from at least one of glass fiber, nonwoven fabric, polyethylene, polypropylene, polyvinylidene fluoride, and ceramics.

[0053] In some embodiments, the separator is a solid electrolyte. The solid electrolyte is disposed between the positive and negative electrodes, serving both to transport ions and to isolate the positive and negative electrodes.

[0054] It should be further noted that the electrode tabs in this embodiment include positive electrode tabs and negative electrode tabs. The positive electrode tab is formed by the portion of the positive electrode plate that does not contain active material, and the negative electrode tab is formed by the portion of the negative electrode plate that does not contain active material. The negative electrode tab and the positive electrode tab can be located together at one end of the electrode assembly or separately at both ends of the electrode assembly.

[0055] According to an embodiment of the present invention, another aspect provides a battery pack comprising a plurality of the aforementioned battery cells.

[0056] The battery pack of this utility model embodiment includes the battery cell described above, and has all the beneficial technical effects of the battery cell, which will not be repeated here.

[0057] It should be noted that the battery cell in this embodiment can be, but is not limited to, lithium-ion batteries, lithium manganese oxide batteries, and nickel-cobalt-manganese ternary material batteries. Specifically, taking lithium-ion batteries as an example, the battery pack in this embodiment can be composed of multiple lithium-ion batteries connected in series, multiple lithium-ion batteries connected in parallel, or multiple lithium-ion batteries prepared by combining them in series and parallel. Specific adjustments can be made according to actual application scenarios and needs; however, this utility model does not impose specific limitations in this regard.

[0058] Although embodiments of the present invention have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of the present invention, and such modifications and variations all fall within the scope defined by the appended claims.

Claims

1. A cell cover assembly, characterized in that, include: The cover plate has through holes along the Z direction; The electrode post includes an electrode post body and an electrode post base disposed at one end of the electrode post body. The electrode post base is provided with an annular rib surrounding the electrode post body. A portion of the electrode post body passes through the through hole. Along the Z direction, the electrode post base is located on one side of the cover plate. A sealing ring is fitted over the pole body and partially passes through the through hole. The end of the sealing ring near the pole base forms an annular flange. The annular flange is located between the cover plate and the pole base. The side of the annular flange facing the pole base has an annular groove corresponding to the annular rib. The annular rib is inserted into the annular groove so that the annular flange abuts against the pole base.

2. The cell cover assembly according to claim 1, characterized in that, The electrode post has a riveted state and an unriveted state. Along the Z direction, the thickness of the cell cover assembly in the unriveted state is greater than the thickness of the cell cover assembly in the riveted state.

3. The cell cover assembly according to claim 2, characterized in that, In the unriveted state, along the Z direction, the height of the annular rib is h1, and the value of h1 is in the range of 0.1mm≤h1≤0.4mm.

4. The cell cover assembly according to claim 2, characterized in that, In the unriveted state, the thickness of the annular rib is d1 in the direction perpendicular to the Z direction, and the value of d1 is in the range of 0mm < d1 ≤ 0.5mm.

5. The cell cover assembly according to claim 2, characterized in that, In the unriveted state, along the Z direction, the groove depth of the annular groove is h2, and the value of h2 is in the range of 0.05mm≤h2≤0.5mm.

6. The cell cover assembly according to claim 2, characterized in that, In the riveted state, along the direction perpendicular to the Z direction, the distance between the annular rib and the annular groove wall is d2, and the value of d2 is in the range of 0.05mm≤d2≤0.15mm.

7. The cell cover assembly according to claim 2, characterized in that, In the riveted state, along the Z direction, the compression height of the annular rib is h3, and the value of h3 is in the range of 0.1mm≤h3≤0.3mm.

8. The cell cover assembly according to any one of claims 1 to 7, characterized in that, Along the Z-direction, the cross-sectional shape of the annular rib is square or circular.

9. A battery cell, characterized in that, include: The housing has a cavity and an opening communicating with the cavity; The electrode assembly is disposed within the cavity and has an electrode tab at one end; The cell cover assembly according to any one of claims 1 to 8, wherein the opening is covered and sealed, and the side of the electrode base away from the cover is welded to the electrode tab.

10. A battery pack, characterized in that, include: The battery cell as described in several claims 9.

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