Battery

Abstract

This application relates to the field of battery technology, and more particularly to a battery. The battery includes: a casing; a first terminal post installed at one end of the casing, the first terminal post having a through hole communicating with the interior of the casing; a current collector assembly including a current collector body and a connecting structure located on one side of the current collector body, the current collector body being located on the side of the first terminal post facing the interior of the casing, the connecting structure passing through the through hole, and the end of the connecting structure away from the current collector body being electrically connected to the first terminal post; wherein, the connecting structure includes a fusible portion, the cross-sectional area of ​​which gradually decreases along the axial direction of the through hole, and the cross-sectional area of ​​the fusible portion is smaller than the cross-sectional area of ​​the through hole. When the battery experiences a short circuit or overload, the connecting structure melts at the location of the minimum cross-sectional area of ​​the fusible portion. The connecting structure will not reconnect after melting, ensuring the safety of the battery.

Description

Technical Field

[0001] This application relates to the field of battery technology, and more particularly to a battery. Background Technology

[0002] With the development of the battery industry, the manufacturing process of cylindrical batteries has become relatively mature, and people have put forward higher requirements for the safety performance of batteries.

[0003] Currently, batteries consist of a casing, battery cells, and connecting tabs. The battery cells and connecting tabs are located inside the casing, and the connecting tabs connect the battery cells to the casing. Folded connecting tabs are bent by methods such as localized thinning and width reduction. When the battery experiences a short circuit or overload, the locally thinned or narrowed area of ​​the connecting tab melts, thus providing protection.

[0004] However, even after the connecting piece melts, a connection may still remain between the cell and the casing, posing a certain safety risk to the battery. Utility Model Content

[0005] Based on this, this application provides a battery to solve the problem in related technologies where the connecting piece may still maintain a connection between the cell and the casing after melting, posing a certain safety risk to the battery.

[0006] This application provides a battery, including:

[0007] case;

[0008] The first pole post is installed at one end of the housing, and a through hole communicating with the inside of the housing is opened on the first pole post;

[0009] The collector plate assembly includes a collector plate body and a connecting structure located on one side of the collector plate body. The collector plate body is located on the side of the first pole facing the inside of the housing. The connecting structure is inserted into the through hole, and the end of the connecting structure away from the collector plate body is electrically connected to the first pole.

[0010] The connecting structure includes a fusible link, and the cross-sectional area of ​​the fusible link gradually decreases along the axial direction of the through hole, with the cross-sectional area of ​​the fusible link being smaller than that of the through hole.

[0011] In one possible implementation, the connection structure includes a connecting post passing through a through hole, with the end of the connecting post away from the collector plate body electrically connected to the first pole post.

[0012] One of the connecting post and the collector plate body is provided with a protrusion, and the free end of the protrusion is electrically connected to the other of the connecting post and the collector plate body. The protrusion forms a fusible part.

[0013] In one possible implementation, the protrusion is a solid structure, with the cross-sectional area of ​​its free end being smaller than the cross-sectional area of ​​the rest of the protrusion; or,

[0014] The area of ​​the manifold body facing the connecting post protrudes towards the connecting post to form a protrusion, and the side of the protrusion away from the connecting post defines a cavity that communicates with the inside of the housing.

[0015] In one possible implementation, the collector plate body has a first protrusion protruding on the side facing the first pole post. The first protrusion passes through the through hole, and the interior of the first protrusion forms a cavity communicating with the interior of the housing. The first protrusion is a connecting structure.

[0016] The fusible part includes a first fusible part and a second fusible part respectively disposed on the side wall of the first protrusion, wherein the end of the first fusible part away from the inside of the housing is connected to the end of the second fusible part facing the inside of the housing;

[0017] The cross-sectional area of ​​the first fuse gradually decreases in the direction away from the interior of the shell, while the cross-sectional area of ​​the second fuse gradually decreases in the direction towards the interior of the shell.

[0018] In one possible implementation, the thickness of the collector plate body is 0.1mm-4mm, and the ratio between the height of the first protrusion and the thickness of the collector plate body is 10-1.

[0019] In one possible implementation, the ratio A between the capacity of the through-hole and the volume of the portion of the connecting structure located within the through-hole satisfies:

[0020] 1 > A ≥ 0.1; and / or,

[0021] The ratio between the minimum cross-sectional area of ​​the fuse section and the cross-sectional area of ​​the through hole is greater than or equal to 0.1; and / or,

[0022] The ratio of the maximum cross-sectional area of ​​the fused section to the minimum cross-sectional area of ​​the fused section is B, and B satisfies:

[0023] 1>B≥0.1.

[0024] In one possible implementation, an insulating element is provided between the current collector body and the first pole post, and the insulating element is configured to isolate the current collector body from the first pole post.

[0025] In one possible implementation, the thickness of the insulation element is 0.01 mm to 0.5 mm; and / or,

[0026] The ratio between the projected area of ​​the first pole on the plane of the collector plate and the projected area of ​​the insulating component on the plane of the collector plate is 0.1-1.

[0027] In one possible implementation, a second protrusion is provided at the end of the housing protruding outward from the housing, and the second protrusion defines a cavity on the side facing inward from the housing, and the first pole post is mounted on the second protrusion.

[0028] In one possible implementation, the battery further includes a cover, a second terminal post, a terminal post base plate, and a current collector. The cover is placed on the end of the housing away from the first terminal post. The terminal post base plate and the current collector are respectively disposed inside the housing. The terminal post base plate is located between the cover and the current collector and is electrically connected to the current collector. The second terminal post passes through the cover and is electrically connected to the terminal post base plate.

[0029] The battery provided in this application includes a casing, a first terminal, and a current collector assembly. The first terminal is mounted at one end of the casing and has a through hole communicating with the interior of the casing. The current collector assembly includes a current collector body and a connecting structure located on one side of the current collector body. The connecting structure passes through the through hole, and the end of the connecting structure away from the current collector body is electrically connected to the first terminal. The connecting structure includes a fusible portion, and the cross-sectional area of ​​the fusible portion gradually decreases along the axial direction of the through hole. When the battery experiences a short circuit or overload, the connecting structure melts at the location of the minimum cross-sectional area of ​​the fusible portion. The cross-sectional area of ​​the fusible portion is smaller than the cross-sectional area of ​​the through hole. A fusible space is formed between the fusible portion and the through hole to accommodate molten material, preventing the connecting structure from re-attaching after melting, thereby providing reliable protection for the battery and ensuring its safety. Attached Figure Description

[0030] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0031] Figure 1 This is a schematic diagram of the battery structure provided in an embodiment of this application;

[0032] Figure 2 for Figure 1 Exploded view of the battery shown;

[0033] Figure 3 A partial cross-sectional view of the first type of battery provided in this application embodiment at the location of the first electrode post;

[0034] Figure 4 A partial cross-sectional view of the second type of battery provided in this application embodiment at the location of the first electrode post;

[0035] Figure 5 A partial cross-sectional view of the third type of battery provided in this application embodiment at the position of the first electrode post;

[0036] Figure 6 A partial cross-sectional view of the fourth type of battery provided in this application embodiment at the position of the first electrode post;

[0037] Figure 7 for Figure 6 A magnified view of a portion of point A in the middle;

[0038] Figure 8 This is a partial cross-sectional view of the battery at the second terminal position, provided in an embodiment of this application.

[0039] Explanation of reference numerals in the attached figures:

[0040] 100 - Housing; 110 - Second protrusion;

[0041] 200 - First pole post; 210 - Through hole;

[0042] 310 - Collector plate body; 321 - Fusible link; 3211 - First fusible link; 3212 - Second fusible link; 322 - Connecting post; 323 - Cavity; 324 - First protrusion; 325 - Welding area; 326 - Cavity;

[0043] 400 - Insulation components;

[0044] 500-Lid;

[0045] 610 - Second pole piece; 620 - Pole piece base plate;

[0046] 700-collector disk;

[0047] 810 - First plastic part; 820 - Second plastic part;

[0048] 910 - Battery cell; 920 - Sealing ring. Detailed Implementation

[0049] To make the objectives, technical solutions, and advantages of this application clearer, the technical solutions in the embodiments of this application will be described in more detail below with reference to the accompanying drawings. In the drawings, the same or similar reference numerals denote the same or similar components or components having the same or similar functions throughout. The described embodiments are some, but not all, of the embodiments of this application. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain this application, and should not be construed as limiting this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application. The embodiments of this application will be described in detail below with reference to the accompanying drawings.

[0050] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, an indirect connection through an intermediate medium, or the internal communication between two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0051] In the description of this application, it should be understood that the terms "upper", "lower", "front", "back", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.

[0052] The terms “first,” “second,” and “third” (if any) in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence.

[0053] Furthermore, the terms “comprising” and “having”, and any variations thereof, are intended to cover non-exclusive inclusion, such that a process, method, system, product, or display that includes a series of steps or units is not necessarily limited to those steps or units that are explicitly listed, but may include other steps or units that are not explicitly listed or that are inherent to such process, method, product, or display.

[0054] In existing technologies, batteries include a casing, a cell, and a connecting piece. The cell and connecting piece are respectively disposed inside the casing, and the connecting piece connects the cell and the casing. When the connecting piece has a flat structure, it often lacks a fusible link, posing a safety risk to the battery. Some batteries use folded connecting pieces, which are bent by methods such as localized thinning or width reduction. When the battery experiences a short circuit or overload, the locally thinned or narrowed area of ​​the connecting piece melts, thus providing protection. However, the connecting piece retains a certain degree of elasticity after bending, and under its own elastic force, a connection may still remain between the cell and the casing after melting, posing a certain safety risk to the battery.

[0055] After repeated consideration and verification, the inventors discovered that if through holes are made in the battery terminals, the current collector assembly is electrically connected to the terminals through a connecting structure extending into the through holes. The connecting structure features a fusible link with a gradually decreasing cross-sectional area along the axis of the through hole, thus reducing the flow area of ​​the fusible link along the axis of the through hole. When the battery experiences a short circuit or overload, the fusible link melts at the location with the smallest cross-sectional area. By setting the cross-sectional area of ​​the fusible link to be smaller than that of the through hole, a gap is formed between the fusible link and the inner wall of the through hole, creating a fusible space for storing molten material and preventing the connecting structure from overlapping on both sides of the fusible link. This reliably protects the battery and ensures its safety.

[0056] In view of this, the inventors designed a battery that utilizes a through-hole on the terminal post that communicates with the interior of the casing. A current collector assembly, comprising a current collector body and a connecting structure, is installed. The connecting structure is located on one side of the current collector body and passes through the through-hole. The end of the connecting structure furthest from the current collector body is electrically connected to the first terminal post. A fusible link with a cross-sectional area that gradually decreases along the axial direction of the through-hole is provided on the connecting structure. In the event of a short circuit or overload, the fusible link melts at its smallest cross-sectional area. The fusible space between the fusible link and the through-hole can store the molten material formed during melting, preventing electrical continuity between the current collector body and the terminal post, thus providing reliable protection for the battery.

[0057] The technical solution of the battery provided in the embodiments of this application will be described in detail below with reference to the accompanying drawings.

[0058] Reference Figures 1 to 6 As shown, the battery provided in this embodiment includes a housing 100, a first terminal 200, and a current collector assembly. The first terminal 200 is mounted on one end of the housing 100, and a through hole 210 communicating with the interior of the housing 100 is formed on the first terminal 200. Optionally, a mounting hole can be provided at one end of the housing 100, and an annular groove can be provided on the outer periphery of the first terminal 200. The first terminal 200 passes through the mounting hole, and the portion of the housing 100 located at the edge of the mounting hole extends into the annular groove. The first terminal 200 and the housing 100 can be sealed by a sealing ring 920. In one possible implementation, when the housing 100 includes a shell portion and a top cover covering the shell portion, the first terminal 200 can be mounted on the top cover.

[0059] The collector plate assembly includes a collector plate body 310 and a connecting structure located on one side of the collector plate body 310. The collector plate body 310 is located on the side of the first pole post 200 facing the interior of the housing 100, and the connecting structure passes through the through hole 210. The end of the connecting structure away from the collector plate body 310 is electrically connected to the first pole post 200.

[0060] The current collector body 310 is electrically connected to the connecting structure. The side of the current collector body 310 facing away from the first electrode post 200 is used for electrical connection with the battery cell 910 in the housing 100. Schematic, after the connecting structure passes through the through hole 210, it can be welded to the electrode post on the side facing the outside of the housing 100. The connecting structure and the first electrode post 200 are made of the same material to facilitate electrical connection between them.

[0061] The connecting structure includes a fusible section 321. Along the axial direction of the through hole 210, the cross-sectional area of ​​the fusible section 321 gradually decreases, and the cross-sectional area of ​​the fusible section 321 is smaller than the cross-sectional area of ​​the through hole 210.

[0062] It should be noted that the cross-sectional area of ​​the fuse 321 is the same as its cross-sectional area in the horizontal section, and the cross-sectional area of ​​the through hole 210 is also the same as its cross-sectional area in the horizontal section. Understandably, the cross-sectional area of ​​the fuse 321 gradually decreases along the axial direction of the through hole 210, and consequently, the flow area of ​​the fuse 321 gradually decreases along the axial direction of the through hole 210, with the flow area at the position of minimum cross-sectional area being the smallest. When the battery experiences a short circuit or overload, the temperature of the fuse 321 at the position of minimum cross-sectional area rises rapidly and it melts. Schematic, the position of minimum cross-sectional area of ​​the fuse 321 is a certain distance from the end of the connecting structure away from the current collector body 310. When the fuse 321 melts at the position of minimum cross-sectional area, the electrical connection between the current collector body 310 and the first terminal 200 can be severed.

[0063] Schematic, along the axial direction of the through hole 210, the cross-sectional area of ​​the portion of the through hole 210 surrounding the fuse portion 321 is of uniform size. Since the cross-sectional area of ​​the through hole 210 is larger than that of the fuse portion 321, and the cross-sectional area of ​​the fuse portion 321 gradually decreases along the axial direction of the through hole 210, a fusing space exists between the fuse portion 321 and the through hole 210. This fusing space can store the molten material generated by the melting of the fuse portion 321, preventing the connection structure from overlapping again after the fuse portion 321 melts.

[0064] The first terminal 200 can be either a negative terminal or a positive terminal. Preferably, the first terminal 200 is a positive terminal. Both the first terminal 200 and the connecting structure are made of aluminum. Aluminum has a relatively low melting point. When the battery experiences a short circuit or overload, the connecting structure is more likely to melt at the location of the minimum cross-sectional area of ​​the fuse part 321, thus reliably protecting the battery.

[0065] It is worth mentioning that the connection structure is not elastic. When the fusible part 321 melts, the parts of the connection structure on both sides of the melt position overlap each other due to elasticity.

[0066] The battery provided in this embodiment has a connection structure including a fusing portion 321 whose cross-sectional area gradually decreases along the axial direction of the through hole 210. The flow area of ​​the fusing portion 321 also gradually decreases along the axial direction of the through hole 210. When the battery experiences a short circuit or overload, the connection structure melts at the location of the minimum cross-sectional area of ​​the fusing portion 321. The cross-sectional area of ​​the fusing portion 321 is smaller than the cross-sectional area of ​​the through hole 210. A fusing space is formed between the fusing portion 321 and the through hole 210 to accommodate molten material, preventing the connection structure from re-attaching after melting, thus providing reliable protection for the battery and ensuring its safety.

[0067] In one embodiment, such as Figures 1-5 As shown, the connection structure includes a connecting post 322 passing through the through hole 210. The end of the connecting post 322 away from the collector plate body 310 is electrically connected to the first pole post 200.

[0068] For example, the cross-sectional shape of the connecting post 322 can match the cross-sectional shape of the through hole 210. The end of the connecting post 322 away from the manifold body 310 can be electrically connected to the first pole post 200 by welding.

[0069] One of the connecting post 322 and the collector plate body 310 is provided with a protrusion, and the free end of the protrusion is electrically connected to the other of the connecting post 322 and the collector plate body 310. The protrusion forms a fusible part 321.

[0070] Specifically, the protrusion can be located at one end of the connecting post 322 facing the collector plate body 310, and this protrusion is electrically connected to the collector plate body 310. Alternatively, the protrusion can also be located on one side of the collector plate body 310 facing the connecting post 322, and this protrusion is electrically connected to the connecting post 322. When the protrusion is located on the connecting post 322, the free end of the protrusion is the end of the protrusion facing the collector plate body 310; when the protrusion is located on the collector plate body 310, the free end of the protrusion is the end of the protrusion facing the connecting post 322.

[0071] The protrusion can be welded to the connecting post 322 or the collector plate body 310 in the welding area 325. The collector plate body 310 and the connecting post 322 are not in complete contact through the protrusion. The welding area between the protrusion and the connecting post 322 or the collector plate body 310 can be set as needed to meet the current carrying capacity under different requirements, as well as the maximum current carrying limit when melting.

[0072] The position with the smallest cross-sectional area of ​​the protrusion can be located at the middle of the protrusion in the axial direction of the through hole 210 or at the free end of the protrusion. When the position with the smallest cross-sectional area of ​​the protrusion melts, the connecting post 322 and the collector plate body 310 are isolated from each other, preventing electrical conduction between the collector plate body 310 and the first pole post 200. In the circumferential direction of the protrusion, a melting space is formed between the protrusion and the through hole 210 to accommodate the molten material.

[0073] In this structure, when the battery experiences a short circuit or overload, the connection between the connecting post 322 and the current collector body 310 is melted, thus protecting the battery.

[0074] In other embodiments, the fuse part 321 may also be provided in the middle of the connecting post 322 along the axial direction of the through hole 210. After the battery is short-circuited or overloaded, the middle position of the connecting post 322 is cut off to protect the battery.

[0075] In a specific embodiment, such as Figures 2-4 As shown, the protrusion is a solid structure, and the cross-sectional area of ​​the free end is smaller than the cross-sectional area of ​​the rest of the protrusion.

[0076] The protrusion can be integrally formed onto the connecting post 322 or the collector plate body 310. The cross-sectional area of ​​the protrusion gradually decreases from the fixed end (the end away from the free end) towards the free end. The cross-sectional area of ​​the connecting post 322 is larger than the cross-sectional area of ​​the free end of the protrusion. The cross-sectional area of ​​the connection structure is smallest at the connection position between the connecting post 322 and the collector plate body 310.

[0077] In this embodiment, when the battery experiences a short circuit or overload, the free end of the protrusion melts, the connection between the protrusion and the connecting post 322 is broken, and the electrical connection between the connecting post 322 and the current collector body 310 is severed, thereby protecting the battery.

[0078] In one possible implementation, such as Figure 5 As shown, the area of ​​the collector plate body 310 facing the connecting post 322 protrudes towards the connecting post 322 to form a protrusion, and the side of the protrusion away from the connecting post 322 defines a cavity 323 that communicates with the interior of the housing 100.

[0079] For example, a protrusion can be formed by stamping the area of ​​the collector plate body 310 facing the connecting post 322, and the free end of the protrusion away from the collector plate body 310 is welded to the connecting post 322.

[0080] In one possible implementation, during the manufacturing process, the protrusion may neck in the middle along its height direction, resulting in the point of minimum cross-sectional area being located at the middle of the protrusion's height. In another possible implementation, the free end of the protrusion has the minimum cross-sectional area, making it the point of minimum cross-sectional area. With this structure, in the event of a short circuit or overload, the point of minimum cross-sectional area will melt, protecting the battery. Compared to a solid protrusion structure, this results in a lighter battery, which is beneficial for increasing the battery's energy density.

[0081] In one possible implementation, the ratio between the height of the connecting post 322 and the depth of the through hole 210 is 0.1-2. The specific ratio can be 0.1, 0.5, 1, 1.5, or 2, etc., and is not limited to a single value. It is worth noting that when the ratio between the height of the connecting post 322 and the depth of the through hole 210 is greater than 1, one end of the connecting post 322 extending into the housing 100 protrudes from the through hole 210. A protrusion can be provided on the connecting post 322, and a groove is provided on one side of the collector plate body 310 corresponding to the connecting post 322 for the end of the connecting post 322 to extend into.

[0082] When the ratio between the height of the connecting post 322 and the depth of the through hole 210 is less than 0.1, the height of the connecting post 322 is too small, which makes it difficult to connect the connecting post 322 to the collector plate body 310. When the ratio between the height of the connecting post 322 and the depth of the through hole 210 is greater than 2, the height of the connecting post 322 is too large, which results in a larger battery weight and reduces the battery's energy density.

[0083] The above ratio range ensures the battery energy density while facilitating the connection between the connecting post 322 and the collector plate body 310.

[0084] In one embodiment, such as Figure 6 and Figure 7 As shown, the collector plate body 310 has a first protrusion 324 protruding on the side facing the first pole post 200. The first protrusion 324 passes through the through hole 210. The interior of the first protrusion 324 forms a cavity 326 that communicates with the interior of the housing 100. The first protrusion 324 is a connecting structure.

[0085] The first protrusion 324 can be a columnar structure, which can be stamped onto the collector plate body 310. The end of the first protrusion 324 away from the interior of the housing 100 can be electrically connected to the first pole post 200 by welding.

[0086] The fusible portion 321 includes a first fusible portion 3211 and a second fusible portion 3212 respectively disposed on the side wall of the first protrusion 324. The end of the first fusible portion 3211 away from the interior of the housing 100 is connected to the end of the second fusible portion 3212 facing the interior of the housing 100.

[0087] The cross-sectional area of ​​the first fusible portion 3211 gradually decreases in the direction away from the interior of the housing 100, and the cross-sectional area of ​​the second fusible portion 3212 gradually decreases in the direction toward the interior of the housing 100.

[0088] During the molding process, the sidewall of the first protrusion 324 develops a necked section along its height direction. The cross-sectional area of ​​this necked section first decreases and then increases along the height direction of the first protrusion 324. The portion of the necked section whose cross-sectional area gradually decreases along the height direction of the first protrusion 324 is the first fusible portion 3211, and the portion whose cross-sectional area gradually increases along the height direction of the first protrusion 324 is the second fusible portion 3212. The position with the smallest cross-sectional area of ​​the necked section is located at the connection between the first fusible portion 3211 and the second fusible portion 3212. When the battery experiences a short circuit or overload, the connection between the first fusible portion 3211 and the second fusible portion 3212 melts, allowing molten material to flow into the fusible space between the fusible portion 321 and the through hole 210, or into the interior of the cavity 326.

[0089] In this structure, when the battery experiences a short circuit or overload, the first protrusion 324 melts at its center in the height direction, thereby cutting off the electrical conduction between the current collector body 310 and the first terminal 200, thus protecting the battery. Simultaneously, the battery's low weight helps to improve its energy density.

[0090] In one possible implementation, the thickness of the collector plate body 310 is 0.1mm-4mm, and the ratio between the height of the first protrusion 324 and the thickness of the collector plate body 310 is 10-1.

[0091] For example, the thickness of the current collector body 310 can be 0.1mm, 0.5mm, 1mm, 2mm, 3mm, or 4mm, etc., and is not limited to a single thickness. When the thickness of the current collector body 310 is less than 0.1mm, the current collector body 310 is too thin, which affects the current carrying capacity of the battery; when the thickness of the current collector body 310 is greater than 4mm, the current collector body 310 is too thick, the battery is heavier, and the battery has a lower energy density.

[0092] For example, the ratio between the height of the first protrusion 324 and the thickness of the manifold body 310 can be 10, 8, 6, 4, 2, or 1. When the ratio is greater than 10, the first protrusion 324 is prone to cracking during stamping, resulting in a low production yield of the manifold body 310. When the ratio is less than 1, the first protrusion 324 may not neck or may not neck significantly during forming, affecting the melting of the first protrusion 324.

[0093] With the above configuration, the current collector body 310 can meet the overcurrent requirements of the battery and ensure the battery's energy density. While ensuring the production yield of the current collector body 310, it also ensures that the first protrusion 324 can be successfully melted in the event of a short circuit or overload.

[0094] In one possible implementation, the ratio between the capacity of the through hole 210 and the volume of the portion of the connecting structure located within the through hole 210 is A, where A satisfies: 1 > A ≥ 0.1.

[0095] In other words, A must be less than 1 while being greater than or equal to 0.1. The value of A can be 0.1, 0.3, 0.5, or 0.8, etc., and is not limited to a single value. A being less than 1 ensures that there is a melting space between the connecting structure and the through hole 210 for storing molten material, preventing the connecting structure from continuing to conduct electricity between the current collector body 310 and the first electrode post 200 after melting. When A is less than 0.1, the volume of the portion of the connecting structure located within the through hole 210 is too small, failing to meet the battery's overcurrent requirements.

[0096] The above configuration ensures that the connection structure will not conduct electricity between the current collector body 310 and the first terminal 200 after the fuse is broken, while also meeting the overcurrent requirements of the battery.

[0097] In one possible implementation, the ratio between the minimum cross-sectional area of ​​the fuse portion 321 and the cross-sectional area of ​​the through hole 210 is greater than or equal to 0.1.

[0098] The ratio between the minimum cross-sectional area of ​​the fuse section 321 and the cross-sectional area of ​​the through hole 210 is less than 1. For example, the ratio can be 0.1, 0.3, 0.5, or 0.8, etc., and is not limited to a single value. The above arrangement also ensures that there is a fuse space between the fuse section 321 and the through hole 210 for storing molten material, and that the position of the minimum cross-sectional area of ​​the fuse section 321 can meet the overcurrent requirements of the battery.

[0099] In one possible implementation, the ratio between the maximum cross-sectional area of ​​the fuse portion 321 and the minimum cross-sectional area of ​​the fuse portion 321 is B, where B satisfies: 1 > B ≥ 0.1.

[0100] For example, the value of B can be 0.1, 0.3, 0.5, or 0.8, etc., and is not limited to a single value. A value of B less than 1 ensures that the connection structure melts at the minimum cross-sectional area of ​​the fuse 321 in the event of a short circuit or overload. When B is less than 0.1, the overcurrent requirement of the battery is not met at the minimum cross-sectional area of ​​the fuse 321. In other words, the above configuration ensures that the connection structure can melt at the minimum cross-sectional area of ​​the fuse 321, while simultaneously meeting the battery's overcurrent requirements.

[0101] like Figure 3 As shown, in one embodiment, an insulating member 400 is provided between the collector plate body 310 and the first pole post 200, and the insulating member 400 is configured to isolate the collector plate body 310 from the first pole post 200.

[0102] For example, adhesive tape can be used as an insulating element 400, which is attached to the current collector body 310 and located between the current collector body 310 and the first terminal 200. The insulating element 400 prevents conductive contact between the current collector body 310 and the first terminal 200, avoiding contact overcurrent between them. This ensures that no electrical continuity occurs between the current collector body 310 and the first terminal 200 after the connection structure is broken, thus guaranteeing battery safety.

[0103] In one possible implementation, the thickness of the insulating component 400 is 0.01mm-0.5mm. The thickness of the insulating component 400 can be 0.01mm, 0.1mm, 0.2mm, 0.3mm, 0.4mm, or 0.5mm, etc., and is not limited to a single thickness. When the thickness of the insulating component 400 is less than 0.01mm, there is a risk of insulation failure; when the thickness of the insulating component 400 is greater than 0.5mm, the insulating component 400 occupies a larger melting space, reducing the energy density of the battery. In other words, the above configuration ensures both the insulation effect of the insulating component 400 and the energy density of the battery.

[0104] In one possible implementation, the ratio between the projected area of ​​the first pole post 200 on the plane of the collector plate body 310 and the projected area of ​​the insulating member 400 on the plane of the collector plate body 310 is 0.1-1.

[0105] For example, the specific value of the above ratio can be 0.1, 0.2, 0.5, 0.6, 0.8, or 1, etc., and is not limited to a single value. When the ratio between the projected area of ​​the first terminal 200 on the plane of the current collector body 310 and the projected area of ​​the insulating component 400 on the plane of the current collector body 310 is less than 0.1, the area of ​​the insulating component 400 is large, which reduces the energy density of the battery and increases the cost of the battery; when the ratio between the projected area of ​​the first terminal 200 on the plane of the current collector body 310 and the projected area of ​​the insulating component 400 on the plane of the current collector body 310 is greater than 1, the area of ​​the insulating component 400 is too small, and the insulating component 400 does not completely isolate the first terminal 200 and the current collector body 310, affecting the safety of the battery.

[0106] The above configuration ensures that the insulating component 400 can completely isolate the first terminal 200 and the current collector body 310, thus guaranteeing the energy density of the battery and controlling the cost of the battery.

[0107] In one embodiment, such as Figures 3-6 As shown, a second protrusion 110 is provided at the end of the housing 100 protruding outward from the housing 100. The second protrusion 110 defines a cavity on the side facing the inside of the housing 100. The first pole post 200 is mounted on the second protrusion 110.

[0108] The second protrusion 110 can be stamped onto the end of the housing 100. When the housing 100 includes a shell portion and a top cover covering the shell portion, the second protrusion 110 is provided on the top cover. Schematic, the mounting hole at the end of the housing 100 passes through the second protrusion 110. The first electrode post 200 is insulated from the end of the housing 100 by a first plastic part 810 and a second plastic part 820, the second plastic part 820 having a protrusion corresponding to the second protrusion 110. After the first electrode post 200 is mounted on the second protrusion 110, the depth to which the first electrode post 200 extends into the housing 100 can be reduced, thereby increasing the energy density of the battery with the same battery shoulder height.

[0109] For example, the height of the second protrusion 110 can be 0.1mm-5mm, such as 0.1mm, 0.5mm, 1mm, 2mm, 3mm or 5mm, etc., and is not limited to a single value. The height of the second protrusion 110 described above can reliably improve the battery energy density while facilitating the processing of the second protrusion 110.

[0110] like Figure 8As shown, the battery also includes a cover 500, a second terminal 610, a terminal base plate 620, and a current collector 700. The cover 500 covers the end of the housing 100 away from the first terminal 200. The terminal base plate 620 and the current collector 700 are respectively disposed inside the housing 100, with the terminal base plate 620 located between the cover 500 and the current collector 700 and electrically connected to the current collector 700. The second terminal 610 passes through the cover 500 and is electrically connected to the terminal base plate 620.

[0111] The second terminal 610 has the opposite polarity to the first terminal 200; when the first terminal 200 is the positive terminal, the second terminal 610 is the negative terminal. Schematic, one side of the current collector 700 is electrically connected to the battery cell 910 in the housing 100, and the other side of the current collector 700 is electrically connected to the terminal base plate 620. The terminal base plate 620 can increase the current-carrying area between the second terminal 610 and the current collector 700, which is beneficial for improving the battery's fast-charging performance. For example, a fixing hole can be formed on the terminal base plate 620, and the second terminal 610 passes through the cover 500, extends into the fixing hole, and is welded and fixed to the terminal base plate 620.

[0112] During battery assembly, the first terminal 200, current collector assembly, cell 910, current collector 700, terminal base plate 620, cover 500 and second terminal 610 can be assembled and fixed outside the housing 100. The fixed components are then fixed to the housing 100. The welding process can be visualized during battery assembly, which is beneficial to improving the battery production yield and production efficiency.

[0113] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application.

Claims

1. A battery, characterized by, include: case; The first pole post is installed at one end of the housing, and the first pole post has a through hole communicating with the inside of the housing; A collector plate assembly includes a collector plate body and a connecting structure located on one side of the collector plate body. The collector plate body is located on the side of the first pole facing the interior of the housing. The connecting structure passes through the through hole, and the end of the connecting structure away from the collector plate body is electrically connected to the first pole. The connection structure includes a fusible section, and the cross-sectional area of ​​the fusible section gradually decreases along the axial direction of the through hole, and the cross-sectional area of ​​the fusible section is smaller than the cross-sectional area of ​​the through hole.

2. The battery of claim 1, wherein, The connection structure includes a connecting post passing through the through hole, and the end of the connecting post away from the collector plate body is electrically connected to the first pole post. One of the connecting post and the collector plate body is provided with a protrusion, and the free end of the protrusion is electrically connected to the other of the connecting post and the collector plate body. The protrusion forms the fuse part.

3. The battery of claim 2, wherein, The protrusion is a solid structure, and the cross-sectional area of ​​the free end is smaller than the cross-sectional area of ​​the rest of the protrusion; or, The area of ​​the collector plate body facing the connecting post protrudes towards the connecting post to form the protrusion, and the side of the protrusion away from the connecting post defines a cavity that communicates with the interior of the housing.

4. The battery of claim 1, wherein, The collector plate body has a first protrusion protruding on the side facing the first pole post. The first protrusion passes through the through hole, and the interior of the first protrusion forms a cavity communicating with the interior of the housing. The first protrusion is the connecting structure. The fusing portion includes a first fusing portion and a second fusing portion respectively disposed on the side wall of the first protrusion, wherein the end of the first fusing portion away from the interior of the housing is connected to the end of the second fusing portion facing the interior of the housing; The cross-sectional area of ​​the first fusible portion gradually decreases in the direction away from the interior of the housing, and the cross-sectional area of ​​the second fusible portion gradually decreases in the direction towards the interior of the housing.

5. The battery of claim 4, wherein, The thickness of the collector plate body is 0.1mm-4mm, and the ratio between the height of the first protrusion and the thickness of the collector plate body is 10-1.

6. The battery of claim 1, wherein, The ratio A between the capacity of the through hole and the volume of the portion of the connecting structure located within the through hole satisfies: 1 > A ≥ 0.1; and / or, The ratio between the minimum cross-sectional area of ​​the fuse portion and the cross-sectional area of ​​the through hole is greater than or equal to 0.1; and / or, The ratio B between the maximum cross-sectional area of ​​the fusible link and the minimum cross-sectional area of ​​the fusible link is satisfied: 1＞B≥0.1。 7. The battery of any one of claims 1-6, wherein, An insulating element is provided between the current collector body and the first pole post, and the insulating element is configured to isolate the current collector body from the first pole post.

8. The battery of claim 7, wherein, The thickness of the insulating element is 0.01mm-0.5mm; and / or, The ratio between the orthographic projection area of ​​the first pole on the plane of the collector plate body and the orthographic projection area of ​​the insulating element on the plane of the collector plate body is 0.1-1.

9. The battery of any one of claims 1-6, wherein, The end of the housing has a second protrusion protruding outward from the housing, and the second protrusion defines a cavity on the side facing inward from the housing. The first pole post is mounted on the second protrusion.

10. The battery of any one of claims 1-6, wherein, The battery also includes a cover, a second terminal post, a terminal post base plate, and a current collector. The cover is disposed on the end of the housing away from the first terminal post. The terminal post base plate and the current collector are respectively disposed inside the housing. The terminal post base plate is located between the cover and the current collector and is electrically connected to the current collector. The second terminal post passes through the cover and is electrically connected to the terminal post base plate.

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