Cylindrical secondary battery, battery pack, and vehicle

Abstract

The present specification provides a cylindrical secondary battery, a battery pack, and a means for transportation, comprising: an electrode assembly having a structure in which a first electrode, a second electrode, and a separator interposed therebetween are sequentially stacked and wound up, the first electrode including a plain portion on one side of a current collector where an active material is not coated, the plain portion including a first electrode tab that is bent from an end of the electrode assembly toward the center of winding or toward the outer edge; a battery can that houses the electrode assembly through an opening formed on one side; a current collector plate including three or more tab coupling portions electrically connected to the first electrode tabs, and a can coupling portion having a continuous outer circumferential surface that extends from an end of the tab coupling portion toward the open portion of the battery can and is electrically connected to an inner surface of the battery can; and a top cap that covers the open portion of the battery can.

Description

[Technical field]

[0001] This application claims the benefit of the filing date of Korean Patent Application No. 10-2021-0030315 filed with the Korean Intellectual Property Office on March 8, 2021, and all contents disclosed in the documents of that Korean patent application are incorporated herein by reference.

[0002] The present invention relates to a cylindrical secondary battery, a battery pack including the same, and a means of transportation. [Background technology]

[0003] Conventional cylindrical secondary batteries generally have a structure in which a tab that connects a jelly roll to an external terminal is welded to the foil of the jelly roll. In cylindrical secondary batteries with this structure, the current path is limited, and the resistance of the jelly roll itself is inevitably very high.

[0004] For this reason, attempts have been made to reduce resistance by increasing the number of tabs connecting the jelly roll to the external terminals, but there is a limit to how much resistance can be reduced to the desired level and how much of a current path can be secured simply by increasing the number of tabs.

[0005] Currently, there is a growing need to develop a jelly roll structure and a current collector plate structure to reduce the resistance of the jelly roll itself, especially for devices that require battery packs with high output and capacity, such as electric vehicles.

[0006] In addition, it is necessary to develop a cylindrical secondary battery having a structure that maintains an improved bonding strength between the current collector and the battery can, and a current collector structure applicable to the cylindrical secondary battery. Summary of the Invention [Problem to be solved by the invention]

[0007] The present invention has been made in consideration of the above-mentioned problems, and has an object to provide a cylindrical secondary battery, a battery pack including the same, and a means of transportation.

[0008] Another object of the present invention is to provide a cylindrical secondary battery including a current collector having a structure capable of improving the bonding strength at the bonding site with the battery can and thereby improving the energy density.

[0009] However, the problems that the present invention aims to solve are not limited to those mentioned above, and other problems not mentioned in this specification will be clearly understood by those of ordinary skill in the art from the description of the invention described below. [Means for solving the problem]

[0010] In order to achieve the above-mentioned object, the present invention provides a cylindrical secondary battery, a battery pack including the same, and a means of transportation according to the following aspects.

[0011] According to one aspect of the present invention, there is provided a cylindrical secondary battery comprising a first electrode, a second electrode, and a separator interposed therebetween, which are sequentially stacked and wound up, the first electrode including a plain portion on one side of a current collector where an active material is not coated, the plain portion including a first electrode tab that is bent from an end of the electrode assembly toward the center of winding or toward the outer periphery; a battery can for accommodating the electrode assembly through an opening formed on one side thereof; a current collector including three or more tab coupling portions electrically connected to the first electrode tabs, and a can coupling portion having a continuous outer circumferential surface extending from ends of the tab coupling portions toward an open portion of the battery can and electrically connected to an inner surface of the battery can; and A top cap for covering the opening of the battery can The present invention provides a cylindrical secondary battery comprising:

[0012] According to one aspect of the present invention, there is provided a battery pack including the cylindrical secondary battery according to the above aspect.

[0013] According to one aspect of the present invention, there is provided an electric vehicle (transportation means) including a battery pack according to the above aspect. Effect of the Invention

[0014] According to one aspect of the present invention, the welding process between the negative electrode current collector plate and the battery can is omitted, so that the manufacturing process of the cylindrical secondary battery can be simplified, thereby improving productivity.

[0015] In addition, since the current collecting plate does not extend to the crimping portion, the possibility of leakage occurring due to partial interference caused by the insertion of the current collecting plate can be prevented.

[0016] However, the effects that can be obtained by the present invention are not limited to the effects described above, and other technical effects not mentioned in this specification will be clearly understood by those of ordinary skill in the art from the description of the invention described below. [Brief description of the drawings]

[0017] [Figure 1] 1 is a diagram illustrating a conventional current collecting plate. [Diagram 2] FIG. 2 is a cross-sectional view of a cylindrical secondary battery to which the conventional current collector plate shown in FIG. 1 is applied. [Diagram 3] 1 illustrates a current collector plate according to an embodiment of the present invention. [Figure 4] 4 shows a side cross section of a cylindrical secondary battery to which the current collector plate shown in FIG. 3 is applied. [Diagram 5] 1 illustrates a battery pack including a cylindrical secondary battery according to one embodiment. [Figure 6] 1 illustrates a vehicle including a battery pack according to one embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0018] Although the present invention may be modified in various ways and may include various embodiments, a specific embodiment will be illustrated in the drawings and described in detail based on the drawings. However, it should be understood that this is not intended to limit the present invention to the specific embodiment, but includes all modifications, equivalents, or alternatives within the technical spirit and technical scope of the present invention.

[0019] In this specification, terms such as first, second, A, B, etc. may be used to describe various components, but the components should not be limited by the terms. The terms are used only to distinguish one component from another. For example, the first component may be named the second component, and similarly, the second component may be named the first component, without departing from the scope of the present invention.

[0020] As used herein, terms such as "and / or" include combinations of multiple associated items or portions of multiple associated items.

[0021] In this specification, when a certain component is expressed in the singular, it may include a plural concept unless otherwise specified in this specification.

[0022] In this specification, unless otherwise specified, the terms "comprise", "have", and the like refer to the mere presence of features, numbers, steps, operations, components, members, etc., described in this specification, or combinations thereof, and do not refer to the exclusion of other features, numbers, etc.

[0023] In this specification, the term "secondary battery" refers to a battery that can be used repeatedly for a long period of time by recharging. Secondary batteries can be classified into nickel-cadmium batteries, lithium-ion secondary batteries, etc., depending on the electrode active material. Secondary batteries can be classified into pouch-type, square-type, cylindrical-type secondary batteries, etc., depending on the shape.

[0024] In this specification, the secondary battery may include a battery can in which the electrode assembly is housed. The battery can may have a cylindrical shape.

[0025] The cylindrical secondary battery may be, for example, a cylindrical secondary battery having a form factor ratio (defined as the diameter of the cylindrical secondary battery divided by its height, i.e., the ratio of height (H) to diameter (Φ)) greater than about 0.4.

[0026] Here, the form factor refers to values ​​indicating the diameter and height of a cylindrical secondary battery.

[0027] In this specification, the term "cylindrical secondary battery" refers to a secondary battery having a cylindrical shape or a shape similar thereto. Cylindrical secondary batteries are widely used in large-capacity electronic and electrical devices due to their high energy density per volume, and may be used in a form in which a plurality of cylindrical secondary batteries are combined to form a battery pack.

[0028] In addition, the term "cylindrical secondary battery" can refer to a structure in which, for example, a rivet inserted into the bottom surface (opposite surface) opposite the opening of a cylindrical secondary battery is used as the cathode, and the battery can itself is used as the anode.

[0029] In this specification, the term "cylindrical secondary battery" may be, for example, 46110 cell, 48750 cell, 48110 cell, 48800 cell, or 46800 cell. In the numerical value indicating the form factor, the first two digits indicate the diameter of the cell, the next two digits indicate the height of the cell, and the final digit 0 indicates that the cross section of the cell is circular. When the cell height is 100 mm or more, three digits are required to indicate the cell height, so the final digit 0 can be omitted.

[0030] Additionally, the term "first electrode" refers to the anode and the term "second electrode" refers to the cathode, but vice versa.

[0031] The battery can is a substantially cylindrical container having an opening on one side thereof, and is made of a conductive metal material. A side surface of the battery can and a side opposite the opening are generally integrally formed. That is, the battery can generally has a shape in which an upper end is open in a height direction thereof and a remaining area of ​​a lower end thereof except for a central portion is closed. A lower surface of the battery can may have a substantially flat shape. The battery can accommodates an electrode assembly through an opening formed on one side thereof in a height direction thereof. The battery can may also accommodate an electrolyte through the opening.

[0032] Unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs.

[0033] Hereinafter, the prior art and preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

[0034] 1, a conventional current collector plate is illustrated, where (a) is a side view of the current collector plate and (b) is a plan view of the current collector plate. The current collector plate 30 extends from a center portion 31 to a can coupling portion 33 and includes a tab coupling portion 32 that couples with the first electrode tab 11, and for example, four tab coupling portions 32 are shown. The can coupling portion 33 of the current collector plate 30 has a discontinuous outer circumferential surface.

[0035] 2, which is a side cross-sectional view of a cylindrical secondary battery using the conventional current collector plate shown in FIG. 1, shows that the can joint 33 of the current collector plate 30 extends to the crimping portion 22 as well as the beading portion 21. In this case, interference occurs between the current collector plate 30 and the injected object, weakening the seal structure of the battery can and causing leakage. In other words, if the can joint 33 extends to the crimping portion 22, the airtightness provided by the seal gasket G1 interposed between the top cap 40 and the battery can 20 at the crimping portion is weakened.

[0036] According to one embodiment of the present invention, there is provided an electrode assembly having a structure in which a first electrode, a second electrode, and a separator interposed therebetween are sequentially stacked and wound, the first electrode including a plain portion on one side of a current collector where an active material is not coated, the plain portion including a first electrode tab bent from an end of the electrode assembly toward the center or the outer edge of the winding; a battery can for accommodating the electrode assembly through an opening formed on one side thereof; a current collector including three or more tab coupling portions electrically connected to the first electrode tabs, and a can coupling portion having a continuous outer circumferential surface extending from ends of the tab coupling portions toward an open portion of the battery can and electrically connected to an inner surface of the battery can; and A top cap for covering the opening of the battery can The present invention provides a cylindrical secondary battery comprising:

[0037] 3 and 4 in relation to the above embodiment, the first electrode tab 11 is coupled to a tab coupling portion 32 of a current collector 30, and the can coupling portion 33 may have a continuous outer circumferential shape. The current collector 30 includes three or more tab coupling portions 32 coupled to the first electrode tabs 11, and a can coupling portion 33 having a continuous outer circumferential surface that extends upward from an end of the tab coupling portion 32 and is electrically coupled to an inner surface of the battery can.

[0038] According to the above embodiment, since the current collector plate has a continuous outer circumferential surface, the connection between the current collector plate and the battery can is stable.

[0039] According to a further embodiment of the present invention, there is provided a cylindrical secondary battery, wherein the tab coupling portions extend from a center of the current collector plate to the can coupling portions and respectively contact the first electrode tabs.

[0040] 3 and 4 in relation to this embodiment, the current collector 30 includes a center portion 31 in a core region of the current collector 30. The center portion 31 may have a substantially circular shape. The tab coupling portion 32 of the current collector 30 extends in an outer circumferential direction from the center portion 31 to a can coupling portion 33, so that the tab coupling portion 32 can be coupled to the first electrode tab 11.

[0041] The cylindrical secondary battery according to the above embodiment achieves efficient coupling between the electrode tabs and the tab coupling portions.

[0042] According to a further embodiment of the present invention, there is provided a cylindrical secondary battery, wherein the tab connection portion forms an angle with an adjacent or other tab connection portion of 40° or more and 140° or less.

[0043] 3 in relation to the above embodiment, any one of the tab coupling parts 32 may have an angle with an adjacent tab coupling part that is the same or different from each other, and may be independently 40° or more, 50° or more, 60° or more, 70° or more, 80° or more, or 90° or more. Meanwhile, referring to FIG. 3, any one of the tab coupling parts 32 may have an angle with an adjacent tab coupling part that is the same or different from each other, and may be independently 140° or less, 130° or less, 120° or less, 110° or less, or 100° or less. Meanwhile, referring to FIG. 3, any one of the tab coupling parts 32 may have an angle with an adjacent tab coupling part that is all 90°.

[0044] The cylindrical secondary battery according to the above embodiment achieves efficient coupling between the electrode tabs and the tab coupling portions.

[0045] According to a further embodiment of the present invention, there is provided a cylindrical secondary battery comprising a beading portion formed on a side edge of the battery can adjacent to the opening and pressed inward.

[0046] 3 and 4, according to the embodiment, an opening (not shown) of a battery can 20 includes a beading portion 21, which is pressed inward adjacent to the opening at the upper end of the battery can 20. The beading portion 21 is formed on the upper portion of the electrode assembly 10. The inner diameter of the battery can 20 in the area where the beading portion 21 is formed is smaller than the diameter of the electrode assembly 10.

[0047] The beading portion 21 refers to an area where a curved groove is formed inside the battery so that the seal gasket G1 can be placed on the top of the battery can 20. The beading portion 21 serves to provide a support surface on which not only the seal gasket G1 but also the top cap 40 can be placed. The beading portion 21 can also provide a support surface on which at least a portion of the periphery of the current collector plate 30 described below can be placed and coupled. That is, at least a portion of the periphery of the current collector plate 30 of the present invention and / or the periphery of the top cap 40 of the present invention can be placed on the upper surface of the beading portion 21.

[0048] For example, in order to stably support at least a portion of the periphery of the current collector 30 and / or the periphery of the top cap 40, at least a portion of the upper surface of the beading portion 21 may have a shape that extends along a direction approximately parallel to the lower surface of the battery can 20, i.e., along a direction approximately perpendicular to the side wall of the battery can 20.

[0049] In the cylindrical secondary battery according to the above embodiment, the can joints are pressed together by forming the beading portion, so that the current collector can be stably fixed in the battery can.

[0050] According to a further embodiment, there is provided a cylindrical secondary battery, in which the can-joining portion of the current collector plate is in contact with the beading portion and is pressed inward.

[0051] In the embodiment, the press-fitting is applied to both the can-joint portion of the current collector plate and the side edge of the battery can, and is a process included in the beading process.

[0052] 3 and 4, the can joint 33 of the current collector 30 and the side edge of the battery can 20 are pressed inwardly together. In this manner, the current collector 30 and the battery can 20 are deformed together and contacted through the beading process. This allows the battery can 20 and the current collector 30 to contact each other without a welding process.

[0053] According to a further embodiment, there is provided a cylindrical secondary battery comprising a crimping portion formed between the opening and the beading portion, the crimping portion extending and bent toward the opening.

[0054] 3 and 4 in relation to the embodiment, the battery can 20 has a crimping portion 22 formed above the beading portion 21. That is, the crimping portion 22 is formed at the upper end of the beading.

[0055] The crimping portion 22 refers to a region that presses the top of the beading portion 21 including a safety device such as a seal gasket G1, and is extended and bent to surround the edge of the top cap 40 disposed on the top of the beading portion 21. The top cap 40 can be fixed onto the beading portion 21 due to the shape of the crimping portion 22.

[0056] In another embodiment, the innermost point of the beading portion 21 may be located radially further inward than the end point of the crimping portion 22. For example, the end point of the crimping portion 22 may be located radially further outward than the innermost point of the beading portion 21. With this structure, the beading portion 21 can be maintained flat even after the sizing process. For example, if the innermost point of the beading portion 21 is located radially further outward than the end point of the crimping portion 22, the radial length of the upper surface of the crimping portion 22 will be longer than the radial length of the beading portion 21. In this case, the area of ​​the upper surface of the crimping portion 22, which is the area that receives pressure in the sizing process, becomes larger, and as a result, the beading portion 21 will not be flat after the sizing process. Therefore, in the present invention, it is preferable that the innermost point of the beading portion 21 is located radially further inward than the end of the crimping portion 22.

[0057] The cylindrical secondary battery according to the above embodiment can achieve perfect sealing.

[0058] According to a further embodiment, there is provided a cylindrical secondary battery, wherein the can joint portion is crimped and fixed by the beading portion.

[0059] 3 and 4 in relation to the above embodiment, when the beading portion 21 is formed on the upper opening side of the battery can, the can joint portion 33 is also pressed, so that the current collector plate 30 can be crimped and fixed in the battery can 20, thereby achieving electrical connection between the battery can 20 and the current collector plate 30.

[0060] In the cylindrical secondary battery according to the above embodiment, a welding process can be omitted by crimping the current collector plate and the battery can, so that a manufacturing process of the cylindrical secondary battery can be simplified.

[0061] According to a further embodiment, there is provided a cylindrical secondary battery, wherein an outer circumferential surface of the can joint portion extends from a lower end of the beading portion to a lower end of the crimping portion, in other words, the can joint portion extends to the beading portion but does not extend to the crimping portion.

[0062] In relation to the above embodiment, and referring to FIG. 4, in the cylindrical secondary battery according to the above embodiment, the current collector 30 extends only to the beading portion 21 and is not inserted into the crimping portion 22 .

[0063] In the cylindrical secondary battery according to the embodiment, since there is no interference between the current collector 30 and the injected object, the sealed structure of the battery can 20 is maintained, and the possibility of leakage can be prevented. In particular, since the can joint portion 33 does not extend to the crimping portion 22, it can be fixed on the beading portion 21 by beading pressure.

[0064] According to a further embodiment, there is provided a cylindrical secondary battery, wherein the outer diameter of the can joint is circular.

[0065] In this regard, and with reference to Figures 3 and 4, the outside diameter of the can joint 33 is circular.

[0066] In the cylindrical secondary battery according to the above embodiment, a stable bond between the current collector and the beading portion 21 of the battery can 20 can be achieved due to the outward repulsive force of the current collector and the bending forming force due to the beading of the battery can 20.

[0067] According to a further embodiment, the second electrode includes a plain portion on one side of a current collector that is not coated with an active material, The non-coating portion includes a second electrode tab that is bent from an end of the electrode assembly toward a winding center or an outer periphery. A cylindrical secondary battery is provided, the battery can having a second electrode terminal electrically connected to the second electrode tab on a surface opposite to the open portion of the battery can.

[0068] The cylindrical secondary battery according to the above embodiment can achieve a reduction in the resistance of the jelly roll electrode assembly.

[0069] According to an embodiment of the present invention, there is provided a battery pack including any one of the cylindrical secondary batteries described above.

[0070] In relation to the above embodiment, referring to FIG. 5, a battery pack 3 including a cylindrical secondary battery 1 in a pack housing 2 is shown.

[0071] The battery pack according to the embodiment has high output and high capacity.

[0072] According to one embodiment of the present invention, there is provided a means of transportation including a battery pack as described above.

[0073] In connection with the above embodiment, and referring to FIG. 6, a transportation means 5 including a battery pack 3 is shown.

[0074] The transportation means according to the embodiment uses a battery pack having high output and high capacity, and is therefore excellent in terms of stability and safety.

[0075] In the above embodiment, the positive active material coated on the positive electrode plate and the negative active material coated on the negative electrode plate may be any active material known in the art without any limitation.

[0076] As an example, the positive electrode active material can be represented by the general chemical formula A[A x M y ]O 2+z (A includes at least one element selected from Li, Na, and K; M includes at least one element selected from Ni, Co, Mn, Ca, Mg, Al, Ti, Si, Fe, Mo, V, Zr, Zn, Cu, Al, Mo, Sc, Zr, Ru, and Cr;

number

[0077] As another example, the positive electrode active material is an alkali metal compound xLiM 1 O2-(1-x)Li2M 2 O3(M 1 contains at least one element having an average oxidation state of 3; M 2 contains at least one element having an average oxidation state of 4;

number

[0078] As another example, the positive electrode active material may be represented by the general chemical formula Li a M 1 x Fe 1-x M 2 y P 1-y M 3 z O 4-z (M 1contains at least one element selected from Ti, Si, Mn, Co, Fe, V, Cr, Mo, Ni, Nd, Al, Mg, and Al; M 2 contains at least one element selected from Ti, Si, Mn, Co, Fe, V, Cr, Mo, Ni, Nd, Al, Mg, Al, As, Sb, Si, Ge, V, and S; M 3 contains halogen group elements optionally including F;

number

[0079] Preferably, the positive electrode active material may contain primary particles and / or secondary particles formed by agglomeration of the primary particles.

[0080] For example, the negative electrode active material may be a carbon material, lithium metal or lithium metal compound, silicon or silicon compound, tin or tin compound, etc. Metal oxides such as TiO2 and SnO2 with a potential of less than 2 V may also be used as the negative electrode active material. The carbon material may be either low crystalline carbon or high crystalline carbon.

[0081] As the separator, a porous polymer film, for example, a porous polymer film made of a polyolefin polymer such as an ethylene homopolymer, a propylene homopolymer, an ethylene / butene copolymer, an ethylene / hexene copolymer, an ethylene / methacrylate copolymer, etc., can be used alone or in a laminate of these. As another example, as the separator, a typical porous nonwoven fabric, for example, a nonwoven fabric made of a high melting point glass fiber, a polyethylene terephthalate fiber, etc. can be used.

[0082] At least one surface of the separator may include a coating layer of inorganic particles. The separator itself may also be made of a coating layer of inorganic particles. The particles constituting the coating layer may have a structure in which they are bound to a binder such that there is an interstitial volume between adjacent particles.

[0083] The inorganic particles may be made of an inorganic material having a dielectric constant of 5 or more. As a non-limiting example, the inorganic particles may be Pb(Zr,Ti)O3 (PZT), Pb 1-x La x Zr 1-y Ti y O3(PLZT), PB(Mg3Nb 2 / 3 )O3-PbTiO3 (PMN-PT), BaTiO3, hafnia (HfO2), SrTiO3, TiO2, Al2O3, ZrO2, SnO2, CeO2, MgO, CaO, ZnO, and Y2O3.

[0084] In the embodiment, the cylindrical secondary battery may include an electrolyte. The electrolyte may be A + B - In this case, the salt may have the structure: + Li + , Na + , K + and combinations of these cations. - is F - , Cl - , Br - , I - , NO3 - , N(CN)2 - , BF4 - , ClO4 - , AlO4 - , AlCl4 - , PF6 - , SbF6 - , AsF6 - , BF2C2O4 - , BC4O8 -, (CF3)2PF4 - , (CF3)3PF3 - , (CF3)4PF2 - , (CF3)5PF - , (CF3)6P - , CF3SO3 - , C4F9SO3 - , CF3CF2SO3 - , (CF3SO2)2N - , (FSO2)2N - , CF3CF2(CF3)2CO - , (CF3SO2)2CH - , (SF5)3C - , (CF3SO2)3C - , CF3(CF2)7SO3 - , CF3CO2 - , CH3CO2 - , SCN - , and (CF3CF2SO2)2N - The anion includes at least one anion selected from the group consisting of:

[0085] The electrolyte can be dissolved in an organic solvent. Examples of the organic solvent include propylene carbonate (PC), ethylene carbonate (EC), diethyl carbonate (DEC), dimethyl carbonate (DMC), dipropyl carbonate (DPC), dimethyl sulfoxide, acetonitrile, dimethoxyethane, diethoxyethane, tetrahydrofuran, N-methyl-2-pyrrolidone (NMP), ethyl methyl carbonate (EMC), γ-butyrolactone, and mixtures thereof.

[0086] Although the above describes a preferred embodiment of the present invention, the present invention is not limited thereto, and can be implemented in various modified forms within the scope of the claims and the detailed description of the invention, which also belong to the scope of the invention. [Explanation of symbols]

[0087] 1. Cylindrical secondary battery 2-Pack Housing 3 Battery pack 5. Transportation 10...electrode assembly 11 First electrode tab 20 Battery can 21 Beading section 22 Crimping section 30 Current collector plate 31...center 32 Tab joint 33 Can joint 40 ···Top Cap G1...Sealing gasket

Claims

1. An electrode assembly having a structure in which a first electrode, a second electrode, and a separator interposed therebetween are sequentially stacked and wound, the first electrode including a plain portion on one side of a current collector where an active material is not coated, the plain portion including a first electrode tab bent from an end of the electrode assembly toward the winding center or the outer periphery; a battery can for accommodating the electrode assembly through an opening formed on one side thereof; a current collector disposed on an open side of the battery can with respect to the electrode assembly, the current collector including three or more tab coupling parts electrically connected to the first electrode tab, the current collector further including a can coupling part having a continuous outer circumferential surface, connecting ends of the three or more tab coupling parts, extending to the open side of the battery can, and electrically connected to an inner surface of the battery can; and a top cap for covering an opening of the battery can; A cylindrical secondary battery comprising:

2. The cylindrical secondary battery according to claim 1 , wherein the tab coupling portions extend from the center of the current collector plate to the can coupling portions and respectively contact the first electrode tabs.

3. The cylindrical secondary battery of claim 1 or 2, wherein the tab coupling portion forms an angle of 40° to 140° with an adjacent tab coupling portion.

4. 4. The cylindrical secondary battery according to claim 1, further comprising a beading portion formed on a side end of the battery can adjacent to the open portion and having a structure pressed inward.

5. The cylindrical secondary battery according to claim 4 , wherein the can-joint portion of the current collector plate is in contact with the beading portion and is press-fitted inward.

6. The cylindrical secondary battery according to claim 5 , further comprising a crimping portion formed between the opening and the beading portion, the crimping portion extending and bent toward the opening.

7. The cylindrical secondary battery according to claim 6 , wherein the can joint portion is crimped and fixed by the beading portion.

8. 8. The cylindrical secondary battery according to claim 6, wherein an outer circumferential surface of the can joint portion extends from a lower end of the beading portion to a lower end of the crimping portion.

9. 9. The cylindrical secondary battery according to claim 1, wherein the outer diameter of the can joint is circular.

10. the second electrode includes a non-coated portion on one surface of a current collector that is not coated with an active material, The non-coating portion includes a second electrode tab bent from an end of the electrode assembly toward a winding center or an outer periphery. The cylindrical secondary battery of claim 1 , further comprising a second electrode terminal electrically connected to the second electrode tab on a surface opposite to the open portion of the battery can.

11. A battery pack comprising the cylindrical secondary battery according to any one of claims 1 to 10.

12. An electric vehicle comprising the battery pack of claim 11.

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