Cylindrical secondary battery

Abstract

A cylindrical secondary battery is disclosed. The cylindrical secondary battery includes: an electrode assembly including a first electrode plate and a second electrode plate; a can having a bottom and cylindrical sides, configured to house the electrode assembly and electrically connected to the first electrode plate; and a cover assembly. The cover assembly includes: a cover plate coupled to one end of the cylindrical sides and electrically connected to the cylindrical sides; and a riveting terminal insulated from the cover plate and electrically connected to the second electrode plate.

Description

[0001] This application claims priority and benefit to Korean Patent Application No. 10-2021-0121009, filed on September 10, 2021, with the Korean Intellectual Property Office, the entire contents of which are incorporated herein by reference. Technical Field

[0002] An aspect of the embodiments of this disclosure relates to a cylindrical secondary battery. Background Technology

[0003] Typically, a cylindrical secondary battery includes a cylindrical electrode assembly, a cylindrical can containing the electrode assembly and electrolyte, and a lid assembly with an upper opening incorporated into the can to seal the can, thereby allowing the current generated in the electrode assembly to flow to an external device.

[0004] Cylindrical secondary batteries typically have a structure in which a can with negative polarity and a cover assembly with positive polarity are insulated from each other by a gasket. Therefore, in order to electrically connect the cylindrical secondary battery to an external device, busbars are usually welded to each of the upper and lower parts of the secondary battery, which limits the structure of the battery pack or battery module that contains (or uses) the cylindrical secondary battery.

[0005] The above information provides a brief background to this disclosure and is intended only to improve the understanding of the background of this disclosure, and may therefore include information that does not constitute related (or prior art). Summary of the Invention

[0006] According to embodiments of this disclosure, a cylindrical secondary battery in which a positive electrode and a negative electrode are arranged in one direction is provided.

[0007] According to embodiments of this disclosure, a cylindrical secondary battery includes: an electrode assembly including a first electrode plate and a second electrode plate; a can having a bottom and a cylindrical side portion, configured to house the electrode assembly and electrically connected to the first electrode plate; and a cover assembly. The cover assembly includes: a cover plate coupled to one end of the cylindrical side portion and electrically connected to the cylindrical side portion; and a riveting terminal insulated from the cover plate and electrically connected to the second electrode plate.

[0008] The cylindrical secondary battery may further include: a first electrode current collector electrically connected to a first electrode plate and electrically connected to a bottom; and a second electrode current collector electrically connected to a second electrode plate and electrically connected to a riveting terminal. The first electrode plate may be a negative electrode plate, and the second electrode plate may be a positive electrode plate.

[0009] The cylindrical secondary battery may also include: an insulator configured to insulate the riveted terminals from the cover plate; and a gasket configured to insulate the cover plate from the cylindrical side of the can.

[0010] The can may include: a rolled edge portion, which is concavely curved at the open end of the cylindrical side; and a pleated portion, spaced apart from the rolled edge portion, with one end of the cylindrical side portion bent within the pleated portion. One end of the pleated portion may be electrically connected to a lid.

[0011] The padding can be separated from the pleated portion and can be located between the outer edge of the cover plate and the rolled edge.

[0012] The riveting terminal may have a protrusion projecting toward the top surface of the cover plate, and the insulator may include a receiving groove for receiving the protrusion.

[0013] The cylindrical secondary battery may also include a stopper that is attached to one end of the riveted terminal facing the electrode assembly, so that the riveted terminal and the insulator are in close contact with each other.

[0014] The stopper may have an opening through which a riveting terminal passes, and the opening in the stopper may have a diameter that gradually increases from its top surface to its bottom surface.

[0015] The riveted terminal may also include a rib extending from the end facing the electrode assembly to make close contact with the insulator.

[0016] The bottom can be welded to or integrated with the cylindrical side, and can include a notch or vent. Attached Figure Description

[0017] The accompanying drawings are included to provide a further understanding of this disclosure, and are incorporated in and form a part of this specification. The drawings illustrate embodiments of the disclosure and, together with the description, describe aspects and features of the disclosure. In the drawings:

[0018] Figure 1A This is a cross-sectional view of a cylindrical secondary battery according to an embodiment;

[0019] Figure 1B It shows Figure 1A A plan view of the bottom and notch of the cylindrical secondary battery shown;

[0020] Figure 1C This is a cross-sectional view showing the bottom and notch of a cylindrical secondary battery according to another embodiment;

[0021] Figure 1D This is a cross-sectional view showing the bottom and notch of a cylindrical secondary battery according to another embodiment;

[0022] Figure 2A This is a cross-sectional view of a cylindrical secondary battery according to another embodiment;

[0023] Figure 2B It shows Figure 2AA plan view of the bottom and notch of the cylindrical secondary battery shown; Figure 3A and Figure 3B This is a plan view showing the terminals of the cover assembly according to various embodiments; and

[0024] Figures 4A to 4C This is a cross-sectional view showing a cover assembly according to various embodiments. Detailed Implementation

[0025] This disclosure may be implemented in many different forms and should not be construed as being limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will be thorough and complete for those skilled in the art and will fully convey the scope of this disclosure to those skilled in the art.

[0026] It will be understood that when an element or layer is referred to as being "on," "connected to," or "bonded to" another element or layer, the element or layer may be directly on, directly connected to, or directly bonded to the other element or layer, or one or more intermediary elements or layers may be present. When an element or layer is referred to as being "directly on," "directly connected to," or "directly bonded to" another element or layer, no intermediary element or layer is present. For example, when a first element is described as being "bonded" or "connected" to a second element, the first element may be directly bonded to or directly connected to the second element, or the first element may be indirectly bonded to or indirectly connected to the second element via one or more intermediary elements.

[0027] In the accompanying drawings, the dimensions of various elements, layers, etc., may be exaggerated for clarity. The same reference numerals designate the same elements. As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items. Furthermore, the use of "may" in describing embodiments of this disclosure refers to "one or more embodiments of this disclosure." Expressions such as "at least one of..." modify the entire column of elements when following (before) a list of elements, without modifying individual elements within that column. As used herein, the term "use" and its variations may be considered synonymous with the term "utilize" and its variations, respectively. As used herein, the terms "substantially," "about," and similar terms are used as approximate terms rather than terms of degree and are intended to account for inherent variations in measurements or calculations that will be recognized by one of ordinary skill in the art.

[0028] It will be understood that although the terms first, second, third, etc., may be used herein to describe various elements, components, regions, layers, and / or portions, these elements, components, regions, layers, and / or portions should not be limited by these terms. These terms are used to distinguish one element, component, region, layer, or portion from another element, component, region, layer, or portion. Therefore, without departing from the teachings of the exemplary embodiments, the first element, component, region, layer, or portion discussed below may be referred to as a second element, component, region, layer, or portion.

[0029] For ease of description, spatial relative terms such as “below,” “under,” “down,” “above,” and “above” may be used herein to describe the relationship between one element or feature and another (additional) element or feature as shown in the figure. It will be understood that spatial relative terms are intended to cover different orientations of the device in use or operation other than those depicted in the figure. For example, if the device in the figure is flipped, an element or feature described as “below” or “under” another element or feature would then be positioned “above” or “above” said other element or feature. Thus, the term “below” can cover both above and below orientations. The device may be otherwise positioned (rotated 90 degrees or in other orientations), and the spatial relative descriptions used herein should be interpreted accordingly.

[0030] The terminology used herein is for the purpose of describing embodiments of this disclosure and is not intended to limit the disclosure. As used herein, unless the context clearly indicates otherwise, the singular forms “a” and “an” are intended to include the plural forms as well. It will also be understood that when the terms “comprising,” “including,” and / or variations thereof are used in this specification, they indicate the presence of the stated features, integrals, steps, operations, elements, and / or components, but do not preclude the presence or addition of one or more other features, integrals, steps, operations, elements, components, and / or groups thereof.

[0031] In the following, a cylindrical secondary battery according to an embodiment of the present disclosure will be described in detail with reference to the accompanying drawings, in which reference is made to... Figure 1A and Figure 1B The upper side is defined as the upper part or upward direction, and the lower side is defined as the lower part or downward direction.

[0032] Figure 1A This is a cross-sectional view of a cylindrical secondary battery according to an embodiment. Figure 1B It shows Figure 1A The diagram shows the bottom and notch of the cylindrical secondary battery. Figure 1C This is a cross-sectional view showing the bottom and notch of a cylindrical secondary battery according to another embodiment. Figure 1DThis is a cross-sectional view showing the bottom and notch of a cylindrical secondary battery according to another embodiment.

[0033] like Figure 1A As shown, the cylindrical secondary battery 10 may include a cylindrical can 110, an electrode assembly 130 inserted into (or housed in) the can 110, a cover assembly 190 coupled to one end of the can 110, and a first electrode current collector 150 and a second electrode current collector 170 electrically connecting the electrode assembly 130 to the cover assembly 190. The cover assembly 190 will be described later.

[0034] The can 110 has a circular bottom 112 and a side 114 extending upward from the bottom 112. The side 114 has a cylindrical shape with an open top (hereinafter referred to as the opening). In the process of manufacturing the secondary battery 10, the electrode assembly 130, together with the electrolyte, is inserted into the can 110 through the opening in the can 110. The electrode assembly 130 can be electrically connected to the can 110 and the cover assembly 190 through a first electrode current collector 150 and a second electrode current collector 170, respectively. The can 110 can be made of steel, steel alloy, nickel-plated steel, nickel-plated steel alloy, aluminum, aluminum alloy, or equivalents thereof, but the material of the can 110 is not limited to these.

[0035] like Figure 1A and Figure 1B As shown, a notch 112a may be provided (or formed) in the bottom 112 as a vent. The notch 112a may have a circular shape with a diameter (e.g., a predetermined diameter) in the circular bottom 112. The notch 112a may be recessed into the inner surface of the bottom 112 (e.g., the plate surface facing the interior of the can 110) by an internal pressing process (e.g., it may be recessed from the inner surface of the bottom 112 (e.g., the plate surface facing the interior of the can 110) by an internal pressing process). In another embodiment, as... Figure 1C As shown, by pressing the inner and outer sides of the bottom 112', a notch 112b can be recessedly formed in each of the inner and outer surfaces of the bottom 112' (e.g., the plate surface facing the outside of the can). In another embodiment, as... Figure 1DAs shown, notch 112c can be formed in the outer surface of the bottom 112” by external pressing. When an event occurs that causes an increase in internal battery pressure due to internal and external factors, gas is generated inside the can 110, thereby increasing the internal pressure of the can 110. When the internal pressure of the can 110 is higher than a certain pressure (e.g., reference pressure) (e.g., increased to above a certain pressure (e.g., reference pressure)), notches 112a, 112b and / or 112c break (or rupture or burst), so that gas, electrode plates, active materials, etc. can be discharged to the outside of the can 110. Each of the notches 112a, 112b and / or 112c is thinner than each of the other portions of the bottom 112, 112' and 112” (e.g., each of the notches 112a, 112b and / or 112c is a thinner portion of the bottom 112, 112' and 112” of the cans 110, 110' and 110”, respectively). For example, notches 112a, 112b and / or 112c serve as vents to prevent the secondary battery 10 from exploding (e.g., to prevent an uncontrolled explosion of the secondary battery 10). Therefore, the vents can be omitted from the cover assembly 190, which will be described later.

[0036] like Figure 1A As shown, a rolled edge (e.g., a rolled edge or rolled portion) 116, recessed inward from the outer peripheral surface of side 114 (or on the outer peripheral surface of side 114), can be configured to be adjacent to an opening in side 114. When the cap assembly 190 is placed on the rolled edge 116, the upper end of can 110 bends inward to secure the cap assembly 190 to can 110. Here, one end of the pleat 118 can be electrically connected to the cap assembly 190, which will be described later. When the electrolyte and electrode assembly 130 is housed in can 110, the cap assembly 190 can be engaged with the opening in can 110 to close and seal the opening.

[0037] Electrode assembly 130 includes a first electrode plate, a second electrode plate, and a separator. The first electrode plate may be a negative electrode plate on which a negative electrode active material layer (e.g., graphite, carbon, etc.) is disposed on its two surfaces (e.g., opposite surfaces). An uncoated portion of the first electrode where the negative electrode active material layer is not applied may be part of the first electrode plate. The second electrode plate may be a positive electrode plate on which a positive electrode active material layer (e.g., transition metal oxide (LiCoO2, LiNiO2, LiMn2O4, etc.)) is disposed on its two surfaces (e.g., opposite surfaces). An uncoated portion of the second electrode where the positive electrode active material layer is not applied may be part of the second electrode plate. A separator may be disposed between the first and second electrode plates to prevent short circuits while allowing lithium ion movement. The first electrode plate may be made of copper (Cu) foil or nickel (Ni) foil, the second electrode plate may be made of aluminum (Al) foil, and the separator may be made of polyethylene (PE) or polypropylene (PP), but this disclosure is not limited thereto.

[0038] The first electrode plate, the second electrode plate, and the diaphragm can be wound into a substantially cylindrical shape and housed in a container 110. The first electrode plate and the second electrode plate can be configured such that the uncoated portions of the first electrode to which the active material is not applied are opposite to each other in the winding.

[0039] For example, refer to Figure 1A The first electrode plate, serving as the negative electrode plate, can be configured such that the uncoated portion of the first electrode faces downwards (e.g., facing the bottom 112). (See reference...) Figure 1A The second electrode plate, serving as the positive electrode plate, can be positioned facing upwards (e.g., facing the cover assembly 190). A diaphragm can be disposed between the first and second electrode plates, and wound in a manner in which the diaphragm insulates the first and second electrode plates from each other. Subsequently, the first electrode current collector 150 can be electrically connected to the uncoated portion of the first electrode, and the second electrode current collector 170 can be electrically connected to the uncoated portion of the second electrode. Therefore, the can 110 and the cover assembly 190 are electrically connected to the electrode assembly 130.

[0040] The first electrode current collector 150 can be electrically connected to the bottom 112 of the can 110 via welding or similar means. Since the first electrode current collector 150 is electrically connected to the uncoated portion of the first electrode, it can be defined as a negative current collector. The second electrode current collector 170 can be electrically connected to the cover assembly 190 via current collector leads 180. Because the second electrode current collector 170 is electrically connected to the uncoated portion of the second electrode, it can be referred to as a positive current collector.

[0041] like Figure 1A As shown, the cover assembly 190 may include a cover plate 191, a riveting terminal 192 coupled to the center of the cover plate 191, an upper insulator 193 insulating the riveting terminal 192 from the cover plate 191, and a stopper 196 securing the riveting terminal 192. The components and / or structure of the insulator may vary depending on the embodiment. For example, in some embodiments, the stopper 196 may be omitted.

[0042] The cover plate 191 is substantially disc-shaped and has an opening (e.g., a hole), with the riveting terminal 192 located in the center of the cover plate 191 within the opening (e.g., the hole). The cover plate 191 may be made of a cold-rolled steel sheet such as SPCE, made of nickel-plated or SUS material. The cover plate 191 may be mounted on a rolled edge 116. The outer edge of the cover plate 191 may be insulated from the side 114 of the can 110 by a gasket 198. The inner edge of the cover plate 191 (e.g., the edge of the opening in the cover plate 191) may be insulated from the riveting terminal 192 by an upper insulator 193.

[0043] The riveting terminal 192 is inserted into an opening in the cover plate 191 and can be electrically connected to the second electrode current collector 170, which serves as the positive current collector, via the current collector lead 180. For example, the riveting terminal 192 can be made of the same or similar material as the current collector lead 180 or the second electrode current collector 170. The portion of the riveting terminal 192 exposed to the upper part of the cover plate 191 (e.g., on the outer surface of the cover plate 191) can have a larger diameter than the portion of the riveting terminal 192 inserted into the opening in the cover plate 191 (e.g., on the inner surface of the cover plate 191). For convenience, the portion of the riveting terminal 192 exposed to the upper part of the cover plate 191 is referred to as the upper end of the riveting terminal 192, and the portion of the riveting terminal 192 facing the second electrode current collector 170 is referred to as the lower end of the riveting terminal 192. The lower end of the riveting terminal 192 can be compressed and deformed by a processing method such as pressing or spinning (e.g., compression molding) to make close contact with the bottom surface (or inner surface) of the cover plate 191. To more securely fix the riveting terminal 192, a hollow annular stop 196 can be additionally provided. After the riveting terminal 192 is inserted into the opening in the cover plate 191, a pressing or spinning process can be performed when the stop 196 is inserted into the lower end (or upper) of the riveting terminal 192. The lower end of the riveting terminal 192 is compressed and deformed to make close contact with the stop 196, and together with the stop 196, makes close contact with the cover plate 191. Because the upper insulator 193 is disposed between the cover plate 191 and the riveting terminal 192, the stop 196 can also make close contact with the upper insulator 193.

[0044] The gasket 198 may be made of an insulating material and may be arranged around a portion of the outer edge and bottom surface of the cover 191 (or extending around a portion of the outer edge and bottom surface of the cover 191), but may not extend to the top surface (or outer surface) of the cover 191. Therefore, when the cover 191 is positioned on the upper part of the rolled edge 116 and the gasket 198 is located therebetween, forming a pleated portion 118, the pleated portion 118 may contact the top surface of the cover 191. In this state, the can 110 and the cover 191 are electrically connected to each other by welding one end of the pleated portion 118 to the cover 191 to form a weld (e.g., a weld seam or weld bead) 197. After welding one end of the pleated portion 118 to the cover 191, a resinous material may be applied around the weld 197 to prevent rusting. The cover plate 191 can be electrically connected to the can 110 via the welding part 197, and therefore can have a negative polarity, with the can 110 being electrically connected to the first electrode current collector 150, which serves as the negative current collector. Thus, since the cover plate 191 serves as the negative electrode and the riveting terminal 192 serves as the positive electrode, both the positive and negative electrodes are provided in the cover assembly 190.

[0045] According to another embodiment, the cylindrical secondary battery may have the following features: Figure 1A The cylindrical secondary battery 10 shown has a different structure than the can shown.

[0046] Figure 2A This is a cross-sectional view of a cylindrical secondary battery according to another embodiment. Figure 2B It shows Figure 2A The diagram shows a plan view of the bottom and notch of the cylindrical secondary battery. Features that are identical or substantially similar to those described above may not be described again in the following text.

[0047] like Figure 2A As shown, the cylindrical secondary battery 20 may include a cylindrical can 210, an electrode assembly 230 inserted into (or housed in) the can 210, a cover assembly 290 coupled to one end of the can 210, and a first electrode current collector 250 and a second electrode current collector 270 electrically connecting the electrode assembly 230 to the cover assembly 290.

[0048] Can 210 may include a separately provided circular bottom 212 and cylindrical sides 214 having open upper and lower sides (or ends). A lid assembly 290 is attached to the open upper end of the side 214, and the bottom 212 is attached to the open lower end of the side 214. The outer edge of the bottom 212 may be welded to the side 214, forming a weld 215, thereby electrically connecting the bottom 212 and the side 214 to each other. Can 210 may be electrically connected to the lid assembly 290 by welding one end of a rolled edge 218 to the lid plate 291 to form a weld 297. Furthermore, a vent 212a may be provided in the bottom 212. The vent 212a may be separately provided (or separately formed) and attached and welded to a through-hole passing through the bottom 212 (see example...). Figure 2B ).

[0049] exist Figure 1A and Figure 2A In the cylindrical secondary batteries 10 and 20 shown, the cover assemblies 190 and 290 can have various structures.

[0050] Figure 3A and Figure 3B This is a plan view showing the terminals of the cover assembly according to an embodiment of the present disclosure. Figures 4A to 4C This is a schematic cross-sectional view of the cover assembly according to various embodiments. For convenience, based on... Figure 1A The embodiments are indicated by reference numerals in the accompanying drawings.

[0051] First, such as Figure 3A As shown, the riveting terminal 192, when attached to the upper end of the cover plate 191, can have a circular shape. In another embodiment, as... Figure 3BAs shown, the attachment of the riveting terminal 192' to the upper end of the cover plate 191' can be square in shape. However, these shapes of the riveting terminals are merely examples, and the riveting terminals are not limited to the shapes described above.

[0052] Figure 4A yes Figure 1A A detailed cross-sectional view of the cover assembly 190 shown. (See attached image.) Figure 4A As shown, the bottom surface of the upper end of the riveting terminal 192 may have a protrusion 192a projecting toward the cover plate 191. The insulator of the cover assembly 190 may be made of PE or PP material and may include an upper insulator 193 and a lower insulator 194. A receiving groove 1930, into which the protrusion 192a is received, may be defined in the top surface of the upper insulator 193. The protrusion 192a may be configured to be adjacent to the portion of the riveting terminal 192 inserted into and passing through the cover plate 191. The riveting terminal 192 and the upper insulator 193 may be more securely joined by the protrusion 192a and the receiving groove 1930.

[0053] The upper insulator 193 may have a circular plate shape in which an opening corresponding to the opening in the cover plate 191 is defined. The hollow inner edge of the upper insulator 193 may extend downward toward the second electrode current collector 170. The circular plate portion of the upper insulator 193 contacts the bottom surface of the upper end of the riveting terminal 192, so that the cover plate 191 is insulated from the upper end of the riveting terminal 192. Therefore, the circular plate portion of the upper insulator 193 may have a size larger than the size of the upper end of the riveting terminal 192. In addition, the circular plate portion of the upper insulator 193 may have a size (e.g., diameter) smaller or larger than the size (e.g., diameter) of the circular plate portion of the lower insulator 194. The downward extension of the upper insulator 193 is inserted into the opening in the cover plate 191, so that the cover plate 191 is insulated from the riveting terminal 192.

[0054] The lower insulator 194 can be configured to be symmetrical to the upper insulator 193 and can have a shape similar to that of the upper insulator 193. For example, the lower insulator 194 can have a circular plate shape in which an opening corresponding to the opening in the cover plate 191 is defined. The hollow inner edge of the lower insulator 194 can extend toward the upper insulator 193. The circular plate portion of the lower insulator 194 contacts the top surface of the stop member 196 to insulate the cover plate 191 from the stop member 196. The circular plate portion of the lower insulator 194 can have a size (e.g., diameter) larger than the size (e.g., diameter) of the stop member 196 and a size (e.g., diameter) smaller than the size (e.g., diameter) of the cover plate 191. The upward extension of the lower insulator 194 is inserted into the opening in the cover plate 191 to insulate the cover plate 191 from the riveting terminal 192. The extended ends of the upper insulator 193 and the lower insulator 194 can be connected to each other by adhesive or the like, or can be pressed together to make them come into close contact during the compression molding of the riveting terminal 192.

[0055] The stopper 196 may have an inclined shape in which the diameter of its inner edge (e.g., the diameter of its opening) gradually increases from its top surface to its bottom surface. Figure 4A The position of the lower end of the riveting terminal 192 before the compression molding and fixing processes is shown by dashed lines. During compression molding, the riveting terminal 192 can be pressed upwards from the position indicated by the dashed lines. When the stop member 196 is tilted inwards, the lower end of the riveting terminal 192 unfolds along the shape of the inner edge of the stop member 196 while being compressed molded. Therefore, the contact area between the riveting terminal 192 and the stop member 196 can be increased to improve the bonding force of the riveting terminal 192. Furthermore, the stop member 196 can be made of the same or similar material as the riveting terminal 192. Therefore, according to various embodiments, the aforementioned current collector lead 180 can be electrically connected to the riveting terminal 192 or electrically connected to the stop member 196.

[0056] Figure 4B It shows the relationship with Figure 4A The embodiments shown are similar to those described, but the insulators have different structures. For example... Figure 4B As shown, the insulator may include an upper insulator 193a, an inner insulator 195a, and a lower insulator 194a.

[0057] The upper insulator 193a may have a hollow circular plate shape. The outer edge of the upper portion of the inner insulator 195a may be configured to be in close contact with the opening in the upper insulator 193a. The inner insulator 195a may be made of PE, PP, or PFA material and may have cylindrical upper and lower ends that bend toward the upper insulator 193a and the lower insulator 194a respectively to extend a certain length (e.g., a predetermined length). The lower insulator 194a may have a hollow circular plate shape, and the outer edge of the lower portion of the inner insulator 195a may be configured to be in close contact with the opening in the lower insulator 194a.

[0058] Figure 4C It shows the relationship with Figure 4B The embodiments shown are similar to those described, but the insulator has a different structure and the blocking element is omitted. Figure 4C As shown, the insulator may include an upper insulator 193b and a lower insulator 194b.

[0059] The upper insulator 193b may have in it Figure 3BThe upper insulator 193a and inner insulator 195a shown are integrated with each other. For example, the upper insulator 193b may have a cylindrical shape integrated with a hollow circular plate-like portion. The cylindrical portion may be inserted into an opening in the cover plate 191. The lower end of the cylindrical portion may be bent toward the lower insulator 194b to extend a certain length (e.g., a predetermined length). The lower insulator 194b may also have a hollow circular plate shape, and the outer edge of the lower portion of the upper insulator 193b may be configured to be in close contact with the opening in the cover plate 191.

[0060] In addition, Figure 4C In the cover assembly 190, the stopper may be omitted, and the riveting terminal 192' may have a rib 1920. The rib 1920 may extend from the lower end of the riveting terminal 192' in a substantially cylindrical shape. When the riveting terminal 192' is compression molded, the rib 1920 may deform outward in the direction of the arrow to make close contact with the lower insulator 194b. Figure 4C The shape of Rib 1920 is shown, and... Figure 4C The process of deforming rib 1920 is shown by dashed lines. Due to this structure, the riveting terminal 192' can be more securely attached to the cover plate 191 without a separate stopper.

[0061] Figure 3A and Figure 3B The shapes of the riveting terminals 192 and 192' shown can be applied to Figure 1A and Figure 2A The secondary batteries 10 and 20 shown are both. Additionally, Figures 4A to 4C The structures of the cover assemblies 190, 190a, and 190b shown can also be applied to Figure 1A and Figure 2A The secondary batteries 10 and 20 are shown. Additionally, when the stopper is omitted, it can be applied... Figures 4A to 4C Any of the insulator structures shown, Figure 4C The structure shown can be applied to the structure of the riveting terminal 192'.

[0062] As described above, because both the positive and negative electrodes are positioned in one direction of the secondary battery (e.g., facing the secondary battery), welding the secondary battery to the busbar is relatively easy and simplifies the connection structure of the busbar. Furthermore, because the welding area is widened by the rivet-type terminal structure, the weldability to the busbar is improved.

[0063] According to embodiments of this disclosure, since both the positive and negative electrodes are arranged in one direction of the secondary battery, welding them to the busbar can be relatively easy, and the connection structure of the busbar can be simplified.

[0064] The above embodiments are merely examples of this disclosure, and therefore, this disclosure is not limited to the foregoing embodiments. Those skilled in the art will understand that various changes in form and detail can be made to the described embodiments without departing from the spirit and scope of this disclosure as defined by the claims and their equivalents.

Claims

1. A cylindrical secondary battery, the cylindrical secondary battery comprising: The electrode assembly includes a first electrode plate and a second electrode plate; A can, having a bottom and cylindrical sides, is configured to house the electrode assembly and is electrically connected to the first electrode plate; as well as A cover assembly includes: a cover plate, which is coupled to one end of the cylindrical side and electrically connected to the cylindrical side; and a riveting terminal, which is insulated from the cover plate and electrically connected to the second electrode plate. A gasket surrounds the outer edge of the cover and a portion of the bottom surface of the cover, and is configured to insulate the cover from the cylindrical side of the can. The can includes: a rolled edge portion, wherein the rolled edge portion is concavely curved inward at the open end of the cylindrical side portion; and a pleated portion, spaced apart from the rolled edge portion, wherein one end of the cylindrical side portion is curved within the pleated portion. One end of the pleated portion contacts the top surface of the cover plate and is electrically connected to the cover plate.

2. The cylindrical secondary battery according to claim 1, further comprising: The first electrode current collector is electrically connected to the first electrode plate and electrically connected to the bottom. as well as The second electrode current collector is electrically connected to the second electrode plate and also electrically connected to the riveting terminal. The first electrode plate is the negative electrode plate, and the second electrode plate is the positive electrode plate.

3. The cylindrical secondary battery according to claim 1, further comprising: An insulator is configured to insulate the riveted terminals from the cover plate.

4. The cylindrical secondary battery according to claim 1, wherein, The padding is spaced apart from the pleated portion and is located between the outer edge of the cover plate and the rolled edge portion.

5. The cylindrical secondary battery according to claim 3, wherein, The riveting terminal has a protrusion projecting toward the top surface of the cover plate, and The insulator includes a receiving groove for accommodating the protrusion.

6. The cylindrical secondary battery according to claim 3, wherein the cylindrical secondary battery further comprises a blocking member, the blocking member being coupled to one end of the riveting terminal facing the electrode assembly, such that the riveting terminal and the insulator are in close contact with each other.

7. The cylindrical secondary battery according to claim 6, wherein, The blocking member has an opening through which the riveting terminal passes, and The opening in the blocking member has a diameter that gradually increases from its top surface to its bottom surface.

8. The cylindrical secondary battery according to claim 3, wherein, The riveting terminal also includes a rib extending from one end facing the electrode assembly to make close contact with the insulator.

9. The cylindrical secondary battery according to claim 1, wherein, The bottom is welded to or integrated with the cylindrical side and includes a notch or vent.

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