Cylindrical battery and current collector applied to said cylindrical battery, battery pack and automobile including such cylindrical battery

Abstract

The present invention provides a current collector for electrically connecting an electrode assembly and a battery housing applied to a cylindrical battery, the current collector including: a loop-shaped portion surrounding a central axis of the electrode assembly to define an opening region at one end of the electrode assembly for exposing an electrode tab made of a non-coating portion, a tab coupling portion extending from an inside of the loop-shaped portion adjacent to the opening region toward the opening region and coupling with the electrode tab exposed from the opening region, and a housing coupling portion extending from an outside of the loop-shaped portion toward an inner circumferential surface of the battery housing and coupling with the battery housing.

Description

[Technical field]

[0001] The present invention relates to a cylindrical battery, a current collector applied to the cylindrical battery, a battery pack including the cylindrical battery, and an automobile. More specifically, an embodiment of the present invention relates to a current collector having a structure capable of preventing damage to a welded portion with an electrode assembly even when an external impact is applied, a cylindrical battery including the current collector, and a battery pack and an automobile including the cylindrical battery.

[0002] This application claims priority to Korean Patent Application No. 10-2021-0169769 filed on December 1, 2021, and Korean Patent Application No. 10-2022-0088437 filed on July 18, 2022, and the contents disclosed in the specification and drawings of said applications are incorporated herein in their entirety. [Background technology]

[0003] Conventional cylindrical 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, and in such a cylindrical battery, the current path is limited, so the resistance of the jelly roll itself is very high.

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

[0005] Therefore, in order to reduce the self-resistance of the jelly roll, it is necessary to develop a new jelly roll structure and a current collector structure suitable for such a jelly roll structure. In particular, the application of such a new jelly roll structure and current collector is even more necessary in devices that require high-output / high-capacity battery packs, such as electric vehicles.

[0006] In addition, battery packs applied to electric vehicles and the like are frequently exposed to vibration and impact in consideration of the usage environment. Therefore, it is necessary to develop a cylindrical battery having a structure that reduces the risk of damage to welded parts even when vibration and external impact are applied, and a current collector structure applied to such a cylindrical battery.

[0007] There is also a need to develop a cylindrical battery having a structure that maintains an improved bonding force between the current collector and the battery housing, and a current collector structure that can be applied to such a cylindrical battery.

[0008] Furthermore, there is a need to develop a cylindrical battery that improves the energy density of the cylindrical battery by minimizing the dead space in the battery housing when the current collector and the battery housing are combined. Summary of the Invention [Problem to be solved by the invention]

[0009] The present invention has been made in consideration of the above-mentioned problems, and an object of the present invention is to provide a current collector having a structure suitable for an electrode assembly having a low resistance structure, and a cylindrical battery including the current collector.

[0010] Another object of the present invention is to provide a current collector having a structure capable of improving the bonding strength at the bonding site between the current collector and the battery housing, and a cylindrical battery including the current collector.

[0011] Another object of the present invention is to provide a current collector having a structure that can significantly reduce the possibility of damage occurring at a welded portion with an electrode assembly and / or a welded portion with a battery housing even when vibration and impact are applied, and a cylindrical battery including the current collector.

[0012] Another object of the present invention is to provide a current collector having a structure capable of improving the energy density of a cylindrical battery, and a cylindrical battery including the current collector.

[0013] Another object of the present invention is to provide a current collector having a structure that can improve the convenience of a welding process for electrically connecting a battery housing and a current collector in manufacturing a cylindrical battery, thereby improving productivity, and a cylindrical battery including the current collector.

[0014] The technical object of the present invention is not limited to the above-mentioned object, and other objects and advantages can be understood from the following description and will be more clearly understood by the embodiments of the present invention. In addition, the objects and advantages of the present invention can be realized by the means and combinations thereof shown in the claims. [Means for solving the problem]

[0015] In order to solve the above problems, a current collector used in a cylindrical battery according to one aspect of the present invention electrically connects an electrode assembly and a battery housing included in the cylindrical battery.

[0016] The current collector may electrically connect an electrode tab formed of a non-coated portion exposed at one end of the electrode assembly to an inner peripheral surface of the battery housing.

[0017] At least a portion of the current collector may be in surface-to-surface contact with the electrode tab, and at least another portion of the current collector may be in surface-to-surface contact with an inner circumferential surface of the battery housing.

[0018] The electrical connection portion of the current collector may be fixed by welding.

[0019] The current collector may include a loop-shaped portion that surrounds a central axis of the electrode assembly to define an open area that exposes an electrode tab made of a plain portion at one side end of the electrode assembly.

[0020] A current collector hole may be provided at the center of the loop-shaped portion, and the current collector hole may communicate with a winding hole of the electrode assembly.

[0021] The loop-shaped portion may form a closed loop surrounding the current collector hole.

[0022] The looped portion may include one or more cut-outs. When the looped portion includes a cut-out, the looped portion may be considered to form a substantially closed loop.

[0023] The current collector may include a tab coupling portion that extends from an inside of the loop portion adjacent to the open area toward the open area and couples with the electrode tab exposed from the open area.

[0024] The tab connection portion may extend from the loop portion in a centripetal direction of the electrode assembly.

[0025] The tab connection may extend in a straight line, an arc, or a combination thereof.

[0026] The current collector may include a housing coupling portion that extends from an outer side of the loop portion toward an inner circumferential surface of the battery housing and is coupled to the battery housing.

[0027] The extending direction of the tab coupling portion and the extending direction of the housing coupling portion may be spaced apart from each other along a circumferential direction of the electrode assembly.

[0028] The loop-shaped portion may include a plurality of first portions spaced apart along the circumferential direction at a first radial position of the exposed region of the electrode tab, a plurality of second portions arranged between adjacent first portions in the circumferential direction at a second radial position outside the first radial position, and a third portion connecting the adjacent first portions and the second portions located between the first portions in the circumferential direction to define a space through which the tab connection portion extends.

[0029] The first portion, the second portion and the third portion may be located on the same plane.

[0030] The tab bond may extend from the second portion toward a center of the electrode assembly.

[0031] A gap may be provided between the tab bond and the third portion.

[0032] The third portion may extend in a straight line, an arc, or a combination thereof.Similarly, the gap may extend in a straight line, an arc, or a combination thereof.

[0033] The open area may extend radially from a center of the electrode assembly.

[0034] The tab connection portion and the housing connection portion may be connected through the loop portion.

[0035] The tab mating portion may extend centripetally from the second portion and the housing mating portion may extend centrifugal from the first portion.

[0036] The housing coupling portion may include a contact portion that contacts the battery housing, and a coupling portion that couples between the contact portion and the loop portion.

[0037] The contact portion may extend circumferentially along an inner peripheral surface of the battery housing.

[0038] The connecting portion may extend in a centrifugal direction and an axial direction of the electrode assembly.

[0039] The connecting portion may include one or more bent portions. The bent portions may be provided in a region adjacent to the contact portion. The bent portions may protrude in a centripetal direction. Optionally, the bent portions may protrude in an axial direction of the electrode assembly.

[0040] One aspect of the present invention provides a cylindrical battery including the current collector described above.

[0041] The cylindrical battery may house a jelly-roll type electrode assembly wound into a cylindrical shape.

[0042] The electrode assembly may include a first electrode tab having an uncoated portion exposed to one side in an axial direction.

[0043] The current collector may contact and be electrically connected to a first electrode tab of the electrode assembly.

[0044] The electrode assembly may include a second electrode tab having an exposed uncoated portion on the other axial side, the second electrode tab having a polarity opposite to that of the first electrode tab.

[0045] An opening may be provided at one axial side of the battery housing, and the housing coupling part may be connected to an inner circumferential surface of the battery housing where the opening is provided.

[0046] A beading portion may be provided on one axial side of the battery housing, the beading portion being pressed in a centripetal direction of the electrode assembly.

[0047] The housing coupling portion may be coupled to an inner circumferential surface of the beading portion.

[0048] The housing coupling portion may be coupled to an inner circumferential surface of the beading portion by welding or the like.

[0049] The cylindrical battery may further include a housing cover that covers the opening.

[0050] The housing cover may be fixed to the battery housing via a seal gasket.

[0051] The housing coupling portion may be interposed and fixed between the seal gasket and the beading portion.

[0052] The second electrode tab may be electrically connected to a terminal provided on the other axial side of the battery housing.

[0053] In order to achieve the above object, a cylindrical battery according to one aspect of the present invention includes an electrode assembly having a first electrode tab and a second electrode tab; a battery housing that receives the electrode assembly through an opening formed on one side thereof; a current collector that contacts the first electrode tab and an inner peripheral surface of the battery housing to electrically connect the first electrode tab and the battery housing, the current collector including: a loop-shaped portion that surrounds a central axis of the electrode assembly on an exposed surface of the first electrode tab to define an opening area that exposes the first electrode tab; a tab coupling portion that extends from an inside of the loop-shaped portion adjacent to the opening area toward the opening area and is coupled to the first electrode tab exposed from the opening area; and a housing coupling portion that extends from an outside of the loop-shaped portion toward the inner peripheral surface of the battery housing and is coupled to the battery housing; a housing cover that covers the opening; and a terminal that penetrates the battery housing on the opposite side to the opening area and is electrically connected to the second electrode tab.

[0054] The loop-shaped portion may include a plurality of first portions spaced apart along the circumferential direction at a first radial position of the exposed region of the first electrode tab, a plurality of second portions arranged between adjacent first portions in the circumferential direction at a second radial position outside the first radial position, and a third portion connecting the adjacent first portions and the second portions located between the first portions in the circumferential direction to define a space through which the tab connection portion extends.

[0055] The tab connection portion may extend from the second portion in a centripetal direction of the electrode assembly.

[0056] A gap may be provided between the tab bond and the third portion.

[0057] The tab connection portion may be linear, arcuate, or a combination thereof. Similarly, the third portion may be linear, arcuate, or a combination thereof. Similarly, the gap may be linear, arcuate, or a combination thereof.

[0058] The open area may extend radially from a center of the electrode assembly.

[0059] A distance from an inner side of the loop portion to an outer periphery of the winding hole of the electrode assembly may be greater than or equal to a length of the tab connection portion.

[0060] An opening may be provided at one axial side of the battery housing, and the housing coupling part may be connected to an inner circumferential surface of the battery housing where the opening is provided.

[0061] The housing coupling portion may be coupled to an inner circumferential surface of a beading portion disposed near an opening of the battery housing and pressed in a centripetal direction.

[0062] The cylindrical battery according to one aspect of the present invention may further include a housing cover covering the opening, and a seal gasket interposed between the housing cover and the battery housing, and the housing coupling portion may be interposed and fixed between the seal gasket and the beading portion.

[0063] A winding hole may be provided at the center of the electrode assembly, and a current collector hole facing the winding hole may be provided at the center of the loop-shaped portion.

[0064] The tab connection portion and the housing connection portion may be connected through the loop portion, the tab connection portion extending centripetally from the second portion and the housing connection portion extending radially from the first portion.

[0065] The loop portion may form a closed loop. Optionally, the loop portion may include one or more cut-outs.

[0066] The housing coupling portion may include a contact portion coupled to an inner circumferential surface of the battery housing, and a coupling portion connecting the contact portion and the loop portion.

[0067] The contact portion may extend circumferentially along an inner peripheral surface of the battery housing.

[0068] The connecting portion may extend in a centrifugal direction and an axial direction of the electrode assembly.

[0069] The connecting portion may include one or more bent portions, which may protrude in a centripetal or axial direction of the electrode assembly.

[0070] A battery pack according to an embodiment of the present invention includes a plurality of the cylindrical batteries described above.

[0071] Moreover, a vehicle according to one aspect of the present invention includes the battery pack described above. Effect of the Invention

[0072] According to one aspect of the present invention, the resistance can be significantly reduced when electrically connecting an electrode assembly and a battery housing.

[0073] Furthermore, according to one embodiment of the present invention, the bonding strength of the bonding site between the current collector and the battery housing can be improved.

[0074] Furthermore, according to one embodiment of the present invention, the energy density of a cylindrical battery can be improved.

[0075] In addition, according to one aspect of the present invention, in manufacturing a cylindrical battery, the convenience of a welding process for electrically connecting a battery housing and a current collector can be improved, thereby improving productivity.

[0076] In addition, according to one aspect of the present invention, even if vibrations and impacts are applied during use of the battery, the possibility of damage occurring at the welded portion between the current collector and the electrode assembly and / or the welded portion between the current collector and the battery housing can be significantly reduced.

[0077] Other specific effects achieved by the present invention will be described in detail later together with the detailed explanation of the invention.

[0078] The following drawings attached to this specification illustrate preferred embodiments of the present invention and, together with the detailed description of the invention, serve to further understand the technical ideas of the present invention. Therefore, the present invention should not be interpreted as being limited to only the matters described in the drawings. [Brief description of the drawings]

[0079] [Figure 1] 1 is a cross-sectional view showing an internal structure of a cylindrical battery according to an embodiment of the present invention. [Diagram 2] FIG. 2 illustrates a current collector according to one embodiment of the present invention. [Diagram 3] FIG. 13 is a diagram showing a current collector according to another embodiment of the present invention. [Figure 4] FIG. 4 is a cross-sectional view showing an internal structure of a cylindrical battery according to another embodiment of the present invention. [Diagram 5] FIG. 13 is a diagram showing a current collector according to still another embodiment of the present invention. [Figure 6] FIG. 4 is a cross-sectional view showing an internal structure of a cylindrical battery according to yet another embodiment of the present invention. [Figure 7] FIG. 13 is a diagram showing a current collector according to still another embodiment of the present invention. [Figure 8] FIG. 2 is a side view of a current collector housing mating portion according to an embodiment of the present invention. [Figure 9] FIG. 2 is a side view of a current collector housing mating portion according to an embodiment of the present invention. [Figure 10] FIG. 2 is a side view of a current collector housing mating portion according to an embodiment of the present invention. [Figure 11] FIG. 13 is a diagram showing a current collector according to still another embodiment of the present invention. [Figure 12] FIG. 13 is a diagram showing a current collector according to still another embodiment of the present invention. [Figure 13] FIG. 13 is a side view of a current collector housing joint according to yet another embodiment of the present invention. [Figure 14] FIG. 13 is a side view of a current collector housing joint according to yet another embodiment of the present invention. [Figure 15] FIG. 13 is a diagram showing a current collector according to still another embodiment of the present invention. [Figure 16] FIG. 13 is a diagram showing a current collector according to still another embodiment of the present invention. [Figure 17] FIG. 17 is a plan view of the current collector of FIG. 16. [Figure 18] FIG. 17 is a plan view of a variation of the current collector of FIG. 16. [Figure 19] 1 is a diagram illustrating a battery pack according to an embodiment of the present invention. [Figure 20] 1 illustrates a vehicle according to an embodiment of the present invention; DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0080] The above-mentioned objects, features and advantages will be described in detail below with reference to the accompanying drawings. Accordingly, those skilled in the art will be able to easily implement the technical idea of ​​the present invention. In addition, in the description of the present invention, if it is determined that a detailed description of related known technology may obscure the gist of the present invention, the detailed description will be omitted. Hereinafter, a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings. In the drawings, the same reference numerals are used to indicate the same or similar components.

[0081] In addition, although the terms "first", "second", etc. are used to indicate various components, these terms are not intended to limit the components. These terms are merely used to distinguish one component from another, and unless otherwise specified, the first component can also be the second component.

[0082] Throughout the specification, unless otherwise stated, each element may be singular or plural.

[0083] Furthermore, when an arbitrary structure is disposed on the "top (or bottom)" of a component or "above (or below)" a component, it does not only mean that the arbitrary structure is disposed in contact with the upper surface (or lower surface) of the component, but also that other structures may be interposed between the component and the arbitrary structure disposed above (or below) the component.

[0084] In addition, when a component is "coupled," "coupled," or "connected" to another component, it includes not only the cases where the components are directly coupled or connected to each other, but also the cases where other components are "interposed" between each component, or the cases where each component is "coupled," "coupled," or "connected" through other components.

[0085] In addition, singular expressions used in this specification include plural expressions unless the context clearly indicates otherwise. In this application, terms such as "comprise" or "include" are not necessarily interpreted as including all of the components or steps described in the specification, and may not include some of the components or steps, and may further include additional components or steps.

[0086] Throughout the specification, unless otherwise specified, "A and / or B" means A, B, or A and B, and "C to D" means C or more and D or less, unless otherwise specified.

[0087] For ease of explanation, in this specification, the direction along the length of the winding shaft of the electrode assembly wound into a jelly roll is referred to as the axial direction (Y-axis). The direction surrounding the winding shaft is referred to as the circumferential direction or outer circumferential direction (X-axis). The directions approaching or moving away from the winding shaft are referred to as the radial direction or radial direction. Of these, the direction approaching the winding shaft is referred to as the centripetal direction, and the direction moving away from the winding shaft is referred to as the centrifugal direction.

[0088] Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings.

[0089] 1, a cylindrical battery 1 according to an embodiment of the present invention includes an electrode assembly 10, a battery housing 20, a current collector (first current collector) 30, a housing cover 40, and a terminal 50. The cylindrical battery 1 may further include a seal gasket G1 and / or an insulating gasket G2 and / or a current collector (second current collector) P and / or an insulator S.

[0090] The electrode assembly 10 includes a first electrode tab 11 and a second electrode tab 12 .

[0091] More specifically, the electrode assembly 10 may be manufactured by winding a laminate formed by sequentially stacking a first electrode, a first separator, a second electrode, and a second separator at least once in a circumferential direction (X direction) around a Y axis. That is, the electrode assembly 10 applied to the embodiment of the present invention may be a jelly roll type electrode assembly. In this case, a first separator and / or a second separator may be provided on an outer circumferential surface of the electrode assembly 10 for insulation from the battery housing 20, or an additional separator or insulating film may be provided.

[0092] The first electrode includes a first electrode collector and a first electrode active material applied on one or both sides of the first electrode collector. An uncoated portion where the first electrode active material is not applied is present at one end of the first electrode collector in the width direction (parallel to the height direction of the cylindrical battery 1 shown in FIG. 1). The uncoated portion is exposed by extending outside the first separator and the second separator, and functions as a first electrode tab 11. The first electrode tab 11 is provided on the upper side of the electrode assembly 10 housed in the battery housing 20 in the height direction (parallel to the height direction of the cylindrical battery 1 shown in FIG. 1). The first electrode tab 11 may be, for example, a negative electrode tab.

[0093] The second electrode includes a second electrode collector and a second electrode active material applied on one or both sides of the second electrode collector. An uncoated portion where the second electrode active material is not applied is present at the other end of the second electrode collector in the width direction (parallel to the height direction of the cylindrical battery 1 shown in FIG. 1). The uncoated portion extends and is exposed outside the first and second separators, and functions as a second electrode tab 12. The second electrode tab 12 is provided on a lower side in the height direction of the electrode assembly 10 accommodated in the battery housing 20. The second electrode tab 12 may be, for example, a positive electrode tab.

[0094] In one embodiment of the present invention, a positive electrode active material coated on an electrode current collector included in a positive electrode and a negative electrode active material coated on a negative electrode current collector included in a negative electrode may be any active material known in the art without limitation.

[0095] 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; x≧0, 1≦x+y≦2, −0.1≦z≦2; x, y, z, and the stoichiometric coefficients of the components included in M ​​are selected such that the compound remains electrically neutral).

[0096] As another example, the positive electrode active material may be 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; 0≦x≦1).

[0097] As yet another example, the positive electrode active material may be represented by the general chemical formula Lia M 1 x Fe 1-x M 2 y P 1-y M 3 z O 4-z (M 1 contains 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 elements, optionally including F; <a≦2、0≦x≦1、0≦y<1、0≦z<1;a、x、y、z、M 1 , M 2 and M 3 wherein the stoichiometric coefficients of the components included are selected to maintain electroneutrality of the compound), or lithium metal phosphate, represented by Li3M2(PO4)3, where M comprises at least one element selected from Ti, Si, Mn, Fe, Co, V, Cr, Mo, Ni, Al, Mg, and Al.

[0098] Preferably, the positive electrode active material may contain primary particles and / or secondary particles formed by aggregation of primary particles.

[0099] For example, the negative electrode active material may be a carbon material, lithium metal or a lithium metal compound, silicon or a silicon compound, tin or a tin compound, etc. Metal oxides such as TiO2 and SnO2 having 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.

[0100] The separator may be 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., used alone or in combination. As another example, the separator may be a conventional porous nonwoven fabric, for example, a nonwoven fabric made of a high melting point glass fiber, a polyethylene terephthalate fiber, etc.

[0101] At least one surface of the separation membrane may include a coating layer of inorganic particles. Alternatively, the separation membrane itself may be made of a coating layer of inorganic particles. The particles constituting the coating layer may have a structure in which they are bound with a binder such that there is an interstitial volume between adjacent particles.

[0102] 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 made of 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.

[0103] The cylindrical battery 1 may include an electrolyte. The electrolyte may be A + B - In this case, the salt may have the structure: + Li + , Na + , K + or a combination thereof. - 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 one or more anions selected from the group consisting of:

[0104] The electrolyte may be dissolved in an organic solvent for use. The organic solvent may be 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, or a mixture thereof.

[0105] The battery housing 20 is a substantially cylindrical container having an opening on one side, and is made of a conductive metal material. As an example, the battery housing 20 may be made of steel or aluminum, but the present invention is not limited thereto. The side surface of the battery housing 20 and a bottom surface (the lower surface in reference to FIG. 1) located opposite the opening are integrally formed. That is, the battery housing 20 has an open upper end in its height direction and a closed lower end. The side walls and bottom of the battery housing 20 may be integrally formed by drawing a metal sheet using a press.

[0106] The lower surface of the battery housing 20 may have a substantially flat shape. The battery housing 20 accommodates the electrode assembly 10 through an opening formed on one side in a height direction of the battery housing 20. The battery housing 20 may also accommodate an electrolyte through the opening.

[0107] The battery housing 20 may include a beading portion 21 formed at an upper end thereof.

[0108] The battery housing 20 may further include a crimping portion 22 formed above the beading portion 21. The beading portion 21 has a shape in which the periphery of the outer circumferential surface of the battery housing 20 is pressed in a centripetal direction to a predetermined depth. The beading portion 21 is formed on the upper portion of the electrode assembly 10. The inner diameter of the battery housing 20 in the region where the beading portion 21 is formed is smaller than the diameter of the electrode assembly 10.

[0109] The beading portion 21 provides a support surface on which the housing cover 40 is placed. The beading portion 21 may also provide a support surface on which at least a portion of the periphery of the current collector 30 described below is placed and coupled. That is, at least a portion of the periphery of the current collector 30 according to an embodiment of the present invention and / or the periphery of the housing cover 40 according to an embodiment of the present invention may be placed on the upper surface of the beading portion 21. As shown in FIG. 1, in order to stably support at least a portion of the periphery of the current collector 30 and / or the periphery of the housing cover 40, at least a portion of the upper surface of the beading portion 21 may extend along a direction approximately parallel to the lower surface of the battery housing 20, i.e., along a direction approximately perpendicular to the sidewall of the battery housing 20.

[0110] The crimping portion 22 is formed on the upper side of the beading portion 21. The crimping portion 22 is extended and bent to enclose the periphery of the housing cover 40 disposed on the upper part of the beading portion 21. Due to the shape of the crimping portion 22, the housing cover 40 is fixed on the beading portion 21. Of course, the crimping portion 22 may be omitted and the housing cover 40 may be fixed while covering the opening of the battery housing 20 through another fixing structure.

[0111] Next, the current collector (first current collector) 30 according to an embodiment of the present invention will be described in detail with reference to FIGS.

[0112] 2, a current collector 30 according to an embodiment of the present invention is accommodated inside a battery housing 20 and is electrically connected to the electrode assembly 10 and the battery housing 20. That is, the current collector 30 electrically connects the electrode assembly 10 and the battery housing 20.

[0113] Preferably, at least a portion of the current collector 30 is in face-to-face contact with the first electrode tab 11 of the electrode assembly 10, and at least another portion of the current collector 30 is in face-to-face contact with the inner circumferential surface of the battery housing 20.

[0114] The current collector 30 includes a loop-shaped portion 31, at least one tab connecting portion 32 extending from the loop-shaped portion 31 and connecting to the first electrode tab 11, and at least one first housing connecting portion 33 extending from an end of the tab connecting portion 32 and connecting to the inner peripheral surface of the battery housing 20.

[0115] The number of the tab coupling portion 32 and the first housing coupling portion 33 may be one or more, and preferably, three to six of them may be arranged at equal intervals along the circumferential direction.

[0116] The loop portion 31 and the at least one tab connecting portion 32 are disposed on the upper portion of the electrode assembly 10, and may be located below the beading portion 21 if the beading portion 21 is formed on the battery housing 20.

[0117] The loop-shaped portion 31 may be provided at the center of the current collector 30. Therefore, the loop-shaped portion 31 may also be referred to as a central portion.

[0118] The loop-shaped portion 31 has a current collector hole H2 formed at a position corresponding to a winding hole H1 formed in the center of the electrode assembly 10. The winding hole H1 and the current collector hole H2, which are in communication with each other, can function as a passage for inserting a welding rod or irradiating a laser for welding a terminal 50 and a current collector (second current collector) P, which will be described later, or for welding the terminal 50 and a lead tab (not shown).

[0119] The loop-shaped portion 31 may be in the form of a substantially circular plate. For example, referring to Fig. 2, the loop-shaped portion 31 may be in the form of a ring-shaped plate having a current collector hole H2 formed at the center thereof.

[0120] At least one of the tab coupling parts 32 may extend radially from the loop-shaped part 31 of the current collector 30 toward the inner wall of the battery housing 20. For example, a plurality of the tab coupling parts 32 may be provided. For example, referring to FIG. 2, the plurality of tab coupling parts 32 may be spaced apart from each other along the periphery of the loop-shaped part 31. As such, the cylindrical battery 1 according to an embodiment of the present invention includes a plurality of tab coupling parts 32, so that the coupling area with the first electrode tab 11 is increased. As a result, the coupling force between the first electrode tab 11 and the tab coupling parts 32 can be secured and electrical resistance can be reduced.

[0121] A longitudinal end of the tab coupling portion 32 may be located inside an innermost portion of the beading portion 21 formed on the battery housing 20. More specifically, a boundary region between the tab coupling portion 32 and the first housing coupling portion 33 may be located inside an innermost portion of the beading portion 21 formed on the battery housing 20 in a direction toward the winding hole H1. With this structure, damage to the coupling portions between the components that may be caused by excessively bending the current collector 30 to position the end of the first housing coupling portion 33 on the beading portion 21 can be prevented.

[0122] Meanwhile, in order to secure a bonding strength and reduce electrical resistance by increasing the bonding area between the current collector 30 and the electrode assembly 10, not only the tab bonding portion 32 but also the loop-shaped portion 31 may be bonded to the first electrode tab 11. The end of the first electrode tab 11 may be formed in a shape bent so as to be parallel to the tab bonding portion 32. When the end of the first electrode tab 11 is formed in this manner and bonded to the tab bonding portion 32 in a state of being bent parallel to the tab bonding portion 32, the bonding area can be increased to improve the bonding strength and reduce the electrical resistance, and the total height of the electrode assembly 10 can be minimized to improve the energy density.

[0123] At least one of the first housing coupling parts 33 may extend from an end of the tab coupling part 32 and be coupled to an inner circumferential surface of the battery housing 20. For example, at least one of the first housing coupling parts 33 may extend from an end of the tab coupling part 32 toward an inner wall of the battery housing 20. For example, a plurality of the first housing coupling parts 33 may be provided. For example, referring to FIG. 2, the plurality of first housing coupling parts 33 may be positioned apart from each other along the periphery of the loop-shaped part 31. Referring to FIG. 1, the plurality of first housing coupling parts 33 may be coupled to a beading part 21 of the inner circumferential surface of the battery housing 20. As shown in FIG. 1, the upper surface of the beading part 21 extends in a direction substantially parallel to the lower surface of the battery housing 20, i.e., in a direction substantially perpendicular to the side wall of the battery housing 20, and the first housing coupling part 33 also extends in the same direction, so that the first housing coupling part 33 can stably contact the beading part 21. In addition, since the first housing coupling portion 33 is in stable contact with the beading portion 21, welding between the two parts is smoothly performed, improving the coupling strength between the two parts and minimizing the increase in resistance at the coupling portion. In addition, since the current collector 30 is coupled to the beading portion 21 of the battery housing 20 instead of to the inner circumferential surface of the cylindrical portion of the battery housing 20, the distance between the current collector 30 and the beading portion 21 can be reduced. Therefore, the dead space inside the battery housing 20 is minimized, and the energy density of the cylindrical battery 1 can be improved.

[0124] 2, the first housing coupling part 33 includes a contact part 33a coupled to an inner peripheral surface of the battery housing 20, and a connecting part 33b connecting the tab coupling part 32 and the contact part 33a.

[0125] The contact portion 33a is coupled to an inner peripheral surface of the battery housing 20. When the beading portion 21 is formed on the battery housing 20, the contact portion 33a may be coupled onto the beading portion 21 as described above. In this case, for stable contact and coupling as described above, both the beading portion 21 and the contact portion 33a may have a shape extending in a direction approximately parallel to the bottom surface of the battery housing 20, i.e., in a direction approximately perpendicular to the side wall of the battery housing 20.

[0126] 2, the connecting portion 33b may have at least one bent portion B where the extending direction is changed between the loop portion 31 and the contact portion 33a. That is, the connecting portion 33b may have, for example, a spring-like structure or a bellows-like structure that can contract and expand within a certain range. This structure of the connecting portion 33b allows the contact portion 33a to be tightly attached onto the beading portion 21 during the process of housing the electrode assembly 10, to which the current collector 30 is connected, into the battery housing 20, even if the height of the electrode assembly 10 varies within a certain range.

[0127] Although the drawings show only one bent portion B, the present invention is not limited to this, and it goes without saying that a plurality of bent portions may be provided.

[0128] For example, in a state where no external force is applied to the current collector 30 and no deformation occurs, the vertical distance D (see FIGS. 8 to 10) between the contact portion 33a and the loop portion 31 is preferably equal to the vertical distance between the upper surface of the beading portion 21 and the loop portion 31 when the electrode assembly 10 to which the current collector 30 is coupled is seated in the battery housing 20, or is preferably formed shorter within the extensible range of the connecting portion 33b. If the connecting portion 33b is configured to satisfy this condition, when the electrode assembly 10 to which the current collector 30 is coupled is seated in the battery housing 20, the contact portion 33a can naturally come into close contact with the beading portion 21 due to the weight of the electrode assembly 10.

[0129] Furthermore, the contractible and expandable structure of the connecting portion 33b can mitigate the impact caused by the movement of the electrode assembly 10 within a certain range even if vibrations and / or impacts occur during use of the cylindrical battery 1 (see FIG. 1) and the electrode assembly 10 moves up and down.

[0130] Meanwhile, when the connecting portion 33b has only one bent portion B, the bent portion B may protrude in a direction toward the winding center of the electrode assembly 10, i.e., in a centripetal direction, unlike the illustrated embodiment (see FIG. 13). The bending direction of the connecting portion 33b is to prevent the bonding portion between the current collector (first current collector) 30 and the electrode assembly 10 and / or the bonding portion between the current collector (first current collector) 30 and the battery housing 20 from being damaged during the sizing process. The sizing process is a compression process for reducing the height occupied by the beading portion 21 region of the battery housing 20 in order to reduce the total height of the cylindrical battery 1 in the manufacture of the cylindrical battery 1. As a result of checking the degree of damage to the welded portion after the sizing process while changing the formation of the bent portion B and the protruding direction of the bent portion B, it was confirmed that almost no damage occurred in the cylindrical battery 1 having a structure in which the connecting portion 33b is bent so that the bent portion B protrudes toward the centripetal direction of the electrode assembly 10.

[0131] 3, a current collector 30 according to another embodiment of the present invention is shown. The current collector 30 according to the other embodiment of the present invention is different from the current collector 30 of FIG. 2 described above only in the shape of the contact portion 33a, and the remaining structure of the current collector 30 described above can be applied in substantially the same manner.

[0132] 3, the contact portion 33a may have a shape in which at least a portion extends along the inner circumferential surface of the battery housing 20. For example, the contact portion 33a may have an arc shape extending in a circumferential direction along a beading portion of the battery housing 20. Also, although not shown, in order to maximize the contact area, the current collector 30 may be configured such that the sum of the extension lengths measured along the outermost edge of each contact portion 33a of at least one first housing coupling portion 33 is substantially equal to the inner circumference of the battery housing 20. As a result, the coupling area can be maximized, thereby improving the coupling force and reducing the electrical resistance.

[0133] 4 and 5, a current collector 30 according to still another embodiment of the present invention is shown. The current collector 30 according to still another embodiment of the present invention differs from the current collector 30 of FIG 3 only in the shape of the connection portion 33b, and the remaining structure of the current collector 30 described above may be substantially similarly applied.

[0134] 4 and 5, the connecting portion 33b may have a shape in which at least a portion extends in a circumferential direction along the inner circumferential surface of the battery housing 20. For example, the contact portion 33a may have an arc shape extending in a circumferential direction along the inner circumferential surface of the beading portion of the battery housing 20, and the connecting portion 33b may also have an arc shape extending in a circumferential direction in a state in which the contact portion 33a is connected to the connecting portion 33b. According to this structure, the area of ​​the current collector 30 is further increased compared to the current collector 30 shown in FIG. 3, so that the effect of reducing the electrical resistance is maximized. Meanwhile, referring to FIG. 5, the current collector 30 may not have the bent portion B, unlike the current collector 30 shown in FIGS. 1 to 3. When the bent portion B is not provided, the raw materials required for manufacturing the current collector 30 can be reduced. This can reduce the manufacturing cost of the current collector 30.

[0135] Hereinafter, a current collector 30 according to another embodiment of the present invention will be described with reference to FIGS.

[0136] The current collector 30 includes a plurality of tab coupling parts 32 extending from a loop-shaped part 31 thereof to be coupled to the first electrode tabs 11, and a plurality of first housing coupling parts 33 extending from the loop-shaped part 31 to be coupled to an inner peripheral surface of the battery housing 20. The tab coupling parts 32 and the first housing coupling parts 33 are indirectly connected to each other through the loop-shaped part 31, and are not directly connected to each other. Therefore, when an external impact is applied to the cylindrical battery 1 according to an embodiment of the present invention, it is possible to minimize the possibility of damage occurring to the coupling parts between the current collector 30 and the electrode assembly 10 and the coupling parts between the current collector 30 and the battery housing 20.

[0137] The loop portion 31 and the plurality of tab connecting portions 32 are disposed on the upper portion of the electrode assembly 10, and are located below the beading portion 21 if the beading portion 21 is formed on the battery housing 20.

[0138] The loop-shaped portion 31 has a current collector hole H2 formed at a position corresponding to a winding hole H1 formed in the center of the electrode assembly 10. The winding hole H1 and the current collector hole H2, which are in communication with each other, can function as a passage for inserting a welding rod or irradiating a laser for welding a terminal 50 and a current collector (second current collector) P, which will be described later, or for welding the terminal 50 and a lead tab (not shown).

[0139] The tab coupling parts 32 may extend radially from the loop part 31 of the current collector 30 toward the side wall of the battery housing 20. The tab coupling parts 32 may be spaced apart from each other along the outer periphery of the loop part 31. Meanwhile, in order to secure a coupling force and reduce electrical resistance by increasing the coupling area between the current collector 30 and the electrode assembly 10, not only the tab coupling parts 32 but also the loop part 31 may be coupled to the first electrode tab 11. An end of the first electrode tab 11 may be formed in a shape bent in parallel to the tab coupling parts 32. When the end of the first electrode tab 11 is formed and coupled to the tab coupling parts 32 in a state where it is bent in parallel to the tab coupling parts 32, the coupling area can be increased to improve the coupling force and reduce the electrical resistance, and the total height of the electrode assembly 10 can be minimized to improve the energy density.

[0140] The first housing coupling parts 33 may extend radially from the loop-shaped part 31 of the current collector 30 toward the inner wall of the battery housing 20. The first housing coupling parts 33 may be spaced apart from each other along the outer periphery of the loop-shaped part 31. At least one first housing coupling part 33 may be located between adjacent tab coupling parts 32. The first housing coupling parts 33 may be coupled to, for example, the beading part 21 of the inner periphery of the battery housing 20. The first housing coupling part 33 may be coupled to an upper surface of the beading part 21 in particular. When such a structure is applied to the cylindrical battery 1 according to an embodiment of the present invention, the first housing coupling part 33 may be naturally placed on the beading part 21 through a process of housing the electrode assembly 10 with the current collector 30 coupled thereto in the battery housing 20. Therefore, a welding process between the battery housing 20 and the current collector 30 can be easily performed. In addition, the upper surface of the beading portion 21 extends in a direction substantially parallel to the lower surface of the battery housing 20, i.e., in a direction substantially perpendicular to the side wall of the battery housing 20, and the first housing coupling portion 33 also extends in the same direction, so that the first housing coupling portion 33 can be stably brought into contact with the beading portion 21. In addition, as the first housing coupling portion 33 stably contacts the beading portion 21 in this manner, the welding between the two parts can be smoothly performed, thereby improving the bonding strength between the two parts and minimizing the increase in resistance at the bonding portion.

[0141] In addition, the first housing coupling portion 33 includes a first contact portion 33a coupled to an inner circumferential surface of the battery housing 20, and a first connecting portion 33b connecting the loop-shaped portion 31 and the first contact portion 33a.

[0142] The first contact portion 33a is coupled to an inner peripheral surface of the battery housing 20. When the beading portion 21 is formed on the battery housing 20, the first contact portion 33a may be coupled onto the beading portion 21 as described above. In this case, for stable contact and coupling as described above, both the beading portion 21 and the first contact portion 33a may extend in a direction substantially parallel to the lower surface of the battery housing 20, i.e., in a direction substantially perpendicular to the sidewall of the battery housing 20.

[0143] 8 to 10, the first connecting portion 33b may have at least one first bent portion B1 where the extending direction is changed between the loop-shaped portion 31 and the first contact portion 33a. That is, the first connecting portion 33b may have, for example, a spring-like structure or a bellows-like structure that can contract and expand within a certain range. Such a structure of the first connecting portion 33b allows the first contact portion 33a to be closely attached to the beading portion 21 by the weight of the electrode assembly 10 during the process of housing the electrode assembly 10, to which the current collector 30 is coupled, in the battery housing 20, even if the height of the electrode assembly 10 varies within a certain range.

[0144] For example, in a state where no external force is applied to the current collector 30 and no deformation occurs, it is preferable that the vertical distance D between the first contact portion 33a and the loop portion 31 is equal to the vertical distance between the upper surface of the beading portion 21 and the loop portion 31 when the electrode assembly 10 with the current collector 30 coupled thereto is seated in the battery housing 20, or is formed shorter within an extensible range of the first connecting portion 33b. If the first connecting portion 33b is configured to satisfy this condition, when the electrode assembly 10 with the current collector 30 coupled thereto is seated in the battery housing 20, the first contact portion 33a can naturally come into close contact with the beading portion 21 due to the weight of the electrode assembly 10.

[0145] Furthermore, the contractible and expandable structure of the first connecting part 33b can reduce, within a certain range, the impact caused by the movement of the electrode assembly 10 even if the electrode assembly 10 moves up and down due to vibration and / or impact generated during use of the cylindrical battery 1 (see FIG. 1). That is, the contractible and expandable structure of the first connecting part 33b can act as a buffer to prevent impact from being transmitted to the coupling portion between the first contact part 33a and the battery housing 20 and the coupling portion between the tab coupling part 32 and the first electrode tab 11.

[0146] 11, a current collector 30 according to still another embodiment of the present invention is shown. The current collector 30 according to still another embodiment of the present invention is different from the current collector 30 described above (the current collector described with reference to FIG. 7) only in the shape of the first contact portion 33a, and the remaining structure of the current collector 30 described above can be applied in substantially the same manner.

[0147] At least a portion of the first contact portion 33a may extend in an arc direction along the inner circumferential surface of the battery housing 20. In this case, in order to maximize the contact area, the current collector 30 may be configured such that the sum of the extension lengths measured along the outermost edges of the first contact portions 33a of the plurality of first housing coupling portions 33 is substantially equal to the inner circumference of the battery housing 20.

[0148] 12, a current collector 30 according to still another embodiment of the present invention is shown. The current collector 30 according to still another embodiment of the present invention differs from the current collector 30 according to the above-described embodiment (the current collector described with reference to FIGS. 7 and 11) in that a second housing coupling portion 34 is further provided, and otherwise the structure of the current collector 30 described above can be applied in substantially the same manner.

[0149] The second housing coupling portion 34 extends from an end of the tab coupling portion 32 and is coupled to an inner circumferential surface of the battery housing 20. The second housing coupling portion 34 is provided on an end of at least one of the plurality of tab coupling portions 32. The second housing coupling portion 34 includes a second contact portion 34a coupled to the inner circumferential surface of the battery housing 20, and a second connecting portion 34b connecting between the loop-shaped portion 31 and the second contact portion 34a.

[0150] The second contact portion 34a is coupled to an inner peripheral surface of the battery housing 20. In the case where a beading portion 21 is formed on the battery housing 20, the second contact portion 34a may be coupled onto the beading portion 21 similarly to the above-described first contact portion 33a. In this case, as described above, for stable contact and coupling, both the beading portion 21 and the second contact portion 34a may have a shape extending in a direction substantially parallel to the lower surface of the battery housing 20, i.e., in a direction substantially perpendicular to the sidewall of the battery housing 20.

[0151] Meanwhile, like the shape of the first contact portion 33a shown in Fig. 11, although not shown, the second contact portion 34a may also have a shape in which at least a portion thereof extends in an arc direction along the inner circumferential surface of the battery housing 20. In this case, in order to maximize the contact area between the current collector 30 and the battery housing 20, the current collector 30 may be configured such that the sum of the extension lengths measured along the outermost edges of the second contact portions 34a of the plurality of second housing coupling portions 34 is substantially equal to the inner circumference of the battery housing 20.

[0152] 13 and 14, the second connecting portion 34b may have at least one second bent portion B2 where the extending direction is changed between the tab coupling portion 32 and the second contact portion 34a, similar to the first connecting portion 33b described above. As described above, the second connecting portion 34b has a contractible and expandable structure due to the formation of the second bent portion B2, which provides advantages and cushioning effects in the assembly process of the cylindrical battery 1. The second bent portion B2 may protrude in the centripetal direction of the electrode assembly 10 as shown in FIG. 13, or may protrude in the central axis direction of the electrode assembly 10 as shown in FIG. 14.

[0153] Although the drawings show only one second bent portion B2, the present invention is not limited thereto, and similar to the first connecting portion 33b described above, multiple second bent portions B2 may also be provided.

[0154] 15, a current collector (first current collector) 30 according to an embodiment of the present invention may have at least one liquid inlet H3. The liquid inlet H3 may be provided, for example, in the tab coupling portion 32. When a plurality of the tab coupling portions 32 are provided, the liquid inlet H3 may be provided in at least one of the tab coupling portions 32. The liquid inlet H3 may be provided, for example, on one or both sides of at least one weld line W formed on the tab coupling portion 32.

[0155] In manufacturing the cylindrical battery 1 according to the embodiment of the present invention, an assembly including the electrode assembly 10 and the current collector (first current collector) 30 may be housed in the battery housing 20, and then an electrolyte may be poured into the battery housing 20. In this case, the electrolyte pouring hole H3 improves the pouring property.

[0156] 14, the first connecting portion 33b of the first housing coupling portion 33 and / or the second connecting portion 34b of the second housing coupling portion 34 according to an embodiment of the present invention may have a shape bent once, and may have a shape bent in a direction different from that shown in FIG. 8 and FIG. 13. That is, the first bent portion B1 formed in the first connecting portion 33b and / or the second bent portion B2 formed in the second connecting portion 34b may have a shape protruding in a direction toward the central axis of the cylindrical battery 1 (see FIG. 1). The bending direction of the first connecting portion 33b and / or the second connecting portion 34b is to prevent a coupling portion between the current collector (first current collector) 30 and the electrode assembly 10 and / or a coupling portion between the current collector (first current collector) 30 and the battery housing 20 from being damaged during a sizing process. The sizing process is a compression process for reducing the height occupied by the beading portion 21 area of ​​the battery housing 20 in order to reduce the total height of the cylindrical battery 1 during the manufacture of the cylindrical battery 1. As a result of checking the degree of damage to the welded portion after the sizing process while changing the formation of the bent portions B1 and B2 and the protruding direction of the bent portions B1 and B2, it was confirmed that almost no damage occurred in a cylindrical battery 1 having a structure in which the bent portions B1 and B2 protrude toward the centripetal direction of the electrode assembly 10 or the central axis direction of the electrode assembly 10.

[0157] Hereinafter, still another embodiment of a current collector that can be used in a cylindrical battery will be described with reference to Figures 16 to 18. The current collector 30 of the still another embodiment can electrically connect between the electrode assembly 10 and the battery housing 20 applied to the cylindrical battery 1.

[0158] The current collector 30 includes a loop-shaped portion 31 that surrounds the central axis of the electrode assembly 10 to define an open area that exposes the first electrode tab 11 of the electrode assembly 10 .

[0159] The loop-shaped portion 31 may include not only a portion extending in the circumferential direction but also a portion extending in the radial direction. The loop-shaped portion 31 may include a plurality of first portions 31a extending in the circumferential direction at a first radial position of the exposed region of the first electrode tab 11, a plurality of second portions 31b arranged between the first portions 31a adjacent in the circumferential direction at a second radial position outside the first radial position, and a third portion 31c connecting the first portions 31a adjacent in the circumferential direction and the second portions 31b positioned between the first portions to define a space in which the tab coupling portion 32 extends. The third portion 31c may extend in a substantially radial direction, but the present invention is not limited thereto. The third portion 31c may extend in a straight line, or may extend in an arc shape or a shape in which a straight line and an arc shape are combined, unlike the illustrated embodiment.

[0160] The first portion 31a, the second portion 31b, and the third portion 31c are in face-to-face contact with the first electrode tab 11. Therefore, the contact area between the first electrode tab 11 and the current collector 30 of the electrode assembly 10 can be further increased.

[0161] The loop-shaped portion 31 may have a closed loop shape surrounding a current collector hole H2 provided at a position corresponding to or along the central axis of the electrode assembly 10. Such a closed loop shape may be a closed loop in which a first portion 31a, a second portion 31b, and a third portion 31c are completely connected, as shown in FIG 17.

[0162] Alternatively, the loop-shaped portion 31 may have a substantial roof shape. That is, as shown in Fig. 18, a cutout 31d may be formed at a specific position of the first portion 31a. In this case, the loop-shaped portion 31 is technically an open loop shape, but has a shape that can be recognized as a closed loop shape overall. It will be obvious to those skilled in the art that the cutout 31d may be formed not only in the first portion 31a but also in the second portion 31b and / or the third portion 31c.

[0163] The current collector 30 includes a tab connection portion 32 connected to the loop portion 31. The tab connection portion 32 may extend from the second portion 31b in a centripetal direction of the electrode assembly 10. The tab connection portion 32 may extend linearly, or may extend in an arc shape or a shape that is a combination of a linear shape and an arc shape, as shown in the drawings.

[0164] The tab connection portion 32 may be disposed substantially in the same plane as the loop portion 31. A gap g may be provided between the tab connection portion 32 and the third portion 31c. The gap g may extend linearly, or may extend in an arc shape or a combination of a linear shape and an arc shape, as shown in the drawings.

[0165] Unlike the tab coupling portion 32 of the other embodiments described above, the tab coupling portion 32 of the present embodiment extends in a centripetal direction from the second portion 31b of the loop-shaped portion 31. That is, the tab coupling portion 32 may be disposed inside an opening region defined by the loop-shaped portion 31. The opening region may extend radially from the center of the electrode assembly 10, and the tab coupling portion 32 may also extend radially within the opening region.

[0166] The distance from the inside of the loop portion 31 to the outer periphery of the winding hole H1 of the electrode assembly 10 may be longer than or equal to the length of the tab coupling portion 32.

[0167] The tab connector 32 may be connected to the first electrode tab 11 of the electrode assembly 10 by welding or the like.

[0168] Alternatively, the first portion 31a and / or the second portion 31b and / or the third portion 31c of the loop portion 31 may be coupled to the first electrode tab 11 by a method such as welding.

[0169] In this manner, each portion of the loop portion 31 can be welded to the first electrode tab 11 either entirely or selectively.

[0170] In addition, the current collector 30 includes a first housing coupling portion 33 that is coupled to the first portion 31 a of the loop portion 31 .

[0171] The first housing coupling portion 33 may extend radially outward from the first portion 31 a of the loop portion 31 .

[0172] A radially outer end of the first housing coupling portion 33 may be coupled to an inner circumferential surface of the battery housing 20 .

[0173] A portion where the first housing coupling portion 33 is coupled to the loop-shaped portion 31 may be disposed radially inward from a portion where the tab coupling portion 32 is coupled to the loop-shaped portion 31 .

[0174] The tab coupling portion 32 and the first housing coupling portion 33 may be connected to each other through the loop-shaped portion 31. That is, the tab coupling portion 32 is connected to the second portion 31b, and the first housing coupling portion 33 is connected to the first portion 31a. The tab coupling portion 32 and the first housing coupling portion 33 are connected to the loop-shaped portion 31 at different positions in the circumferential direction, and are also connected to the loop-shaped portion 31 at different positions in the radial direction.

[0175] As a result, when vibrations or impacts are applied to the cylindrical battery, the vibrations or impacts transmitted through the first housing coupling part 33 can be absorbed or buffered by the geometric shape of the loop-shaped part 31. That is, since a gap exists between the third part 31c of the loop-shaped part 31 and the tab coupling part 32, the vibrations or impacts applied from the outside are transmitted to the tab coupling part 32 through the third part 31c. In this case, the number of paths through which the vibrations or impacts are transmitted is increased, thereby mitigating the vibrations and impacts.

[0176] The first housing coupling portion 33 may include a first contact portion 33a that contacts an inner circumferential surface of the battery housing 20, and a first connecting portion 33b that connects the first contact portion 33a and the loop-shaped portion 31. The first connecting portion 33b is disposed radially inward from the first contact portion 33a and radially outward from the first portion 31a of the loop-shaped portion 31.

[0177] That is, a radial outer end of the first connecting portion 33b may be connected to the first contact portion 33a, and a radial inner end of the first connecting portion 33b may be connected to the first portion 31a of the loop-shaped portion 31.

[0178] The first contact portion 33a may be provided at a radially outer end of the first housing coupling portion 33 and extend in a circumferential direction. The first contact portion 33a may extend in both directions along the circumferential direction from a radially outer end of the first coupling portion 33b.

[0179] The first contact portion 33a may have an arc shape. Preferably, the first contact portion 33a may have a shape corresponding to an inner circumferential surface and / or a beading portion 21 of the battery housing 20 with which the first contact portion 33a comes into contact.

[0180] The curvature of the outermost end of the arc-shaped first contact portion 33 a may correspond to the curvature of the inner circumferential surface of the battery housing 20 .

[0181] The first connection portion 33b may extend in the radial direction and the axial direction of the electrode assembly 10. The first connection portion 33b may extend in a direction away from the electrode assembly in the axial direction as it extends radially outward.

[0182] The first connecting portion 33b may extend straight.

[0183] The first connecting portion may include one or more first bent portions as described above, but in the embodiment, the first bent portions are omitted and a simple first connecting portion 33b is illustrated.

[0184] 1 and 6, the housing cover 40 covers the opening formed on one side of the battery housing 20. The housing cover 40 may be fixed by a crimping portion 22 formed on the upper end of the battery housing 20. In this case, a seal gasket G1 may be interposed between the battery housing 20 and the housing cover 40 to improve the fixing force and the sealing of the battery housing 20. The housing cover 40 does not have to be a part that functions as a current path. Therefore, as long as the battery housing 20 and the housing cover 40 are firmly fixed to each other through welding or fixing with the application of other parts, and the sealing of the opening of the battery housing 20 can be ensured, the application of the seal gasket G1 is not essential.

[0185] Meanwhile, according to an embodiment in which the seal gasket G1 is applied, the seal gasket G1 may be substantially ring-shaped and surround the outer periphery of the housing cover 40. The seal gasket G1 may cover the upper surface, the lower surface, and the side surface of the housing cover 40 at the same time.

[0186] The radial length of the portion of the seal gasket G1 covering the lower surface of the housing cover 40 may be shorter or equal to the radial length of the portion of the seal gasket G1 covering the upper surface of the housing cover 40. If the radial length of the portion of the seal gasket G1 covering the lower surface of the housing cover 40 is too long, the seal gasket G1 may press the current collector 30 during the process of compressing the battery housing 20 vertically, and the current collector 30 and / or the battery housing 20 may be deformed. Therefore, if the radial length of the portion of the seal gasket G1 covering the lower surface of the housing cover 40 is designed to be short to a certain level, the deformation of the current collector 30 and / or the battery housing 20 can be prevented. Specifically, as shown in FIG. 1 and FIG. 6, the radial length of the portion of the seal gasket G1 covering the lower surface of the housing cover 40 may be formed shorter than the radial length of the portion of the seal gasket G1 covering the upper surface of the housing cover 40.

[0187] Meanwhile, the contact portion 33a may be interposed and fixed between the beading portion 21 of the battery housing 20 and the seal gasket G1. That is, in a state in which the contact portion 33a is interposed between the beading portion 21 of the battery housing 20 and the seal gasket G1, the contact portion 33a may be fixed by the crimping force of the crimping portion 22.

[0188] Also, a welded portion may be formed between the beading portion 21 of the battery housing 20 and the contact portion 33a of the current collector 30. For example, the contact portion 33a may not be fixed reliably by crimping force alone. Alternatively, if the seal gasket G1 is shrunk by heat or the crimping portion 22 is deformed by an external impact, the bonding force between the contact portion 33a of the current collector 30 and the battery housing 20 may be reduced. Therefore, the contact portion 33a may be fixed to the battery housing 20 by welding while the contact portion 33a is placed on the beading portion 21 of the battery housing 20. Then, the housing cover 40 wrapped by the seal gasket G1 is placed on the contact portion 33a to form the crimping portion 22, thereby completing the cylindrical battery 1. In this case, the welding method may be, for example, laser welding, resistance welding, ultrasonic welding, etc., but is not limited thereto.

[0189] The housing cover 40 may include a vent portion 41 formed to prevent an increase in internal pressure due to gas generated inside the battery housing 20. The vent portion 41 is formed in a part of the housing cover 40 and corresponds to a region structurally weaker than the surrounding region so as to be easily broken when internal pressure is applied. The vent portion 41 may be, for example, a region having a thickness thinner than that of the surrounding region.

[0190] The height of the housing cover 40 may be lower than the height of the crimping portion 22. In this case, the cylindrical battery 1 may be flipped 180° and attached to a predetermined tray. Because there is a height difference between the housing cover 40 and the crimping portion 22, only the crimping portion 22 contacts the surface of the tray, and a gap exists between the housing cover 40 and the surface of the tray. The gap can provide a space for gas to escape from inside the battery housing 20.

[0191] The terminal 50 is electrically connected to the second electrode tab 12 of the electrode assembly 10 by penetrating the battery housing 20 on the opposite side of the open portion of the battery housing 20. The terminal 50 may penetrate substantially the center of the lower surface of the battery housing 20. The terminal 50 may be electrically connected to the electrode assembly 10 by, for example, being coupled to a current collector (second current collector) P coupled to the second electrode tab 12 or being coupled to a lead tab (not shown) coupled to the second electrode tab 12. Thus, the terminal 50 has the same polarity as the second electrode of the electrode assembly 10 and may function as a second electrode terminal T2. When the second electrode tab 12 is a positive electrode tab, the terminal 50 functions as a positive electrode terminal. Considering the polarity and function of the terminal 50, the terminal 50 should be insulated from the battery housing 20 having the opposite polarity. Therefore, an insulating gasket G2 may be applied between the terminal 50 and the battery housing 20. Alternatively, insulation may be achieved by coating a part of the surface of the terminal 50 with an insulating material.

[0192] For the same reason, the second electrode tab 12 and / or the current collector (second current collector) P must be kept insulated from the battery housing 20. For this reason, an insulator S may be interposed between the second electrode tab 12 and the battery housing 20 and / or between the current collector (second current collector) P and the battery housing 20. When the insulator S is applied, the terminal 50 may penetrate the insulator S for electrical connection with the second electrode tab 12.

[0193] Meanwhile, in one embodiment of the present invention, the entire surface of the battery housing 20 may function as the first electrode terminal T1. For example, when the first electrode tab 11 is a negative electrode tab, the first electrode terminal T1 may be a negative electrode terminal. The cylindrical battery 1 according to one embodiment of the present invention has a structure in which the terminal 50 exposed on the lower surface located opposite the open portion of the battery housing 20 and the remaining area on the lower surface of the battery housing 20 excluding the area occupied by the terminal 50 are used as the second electrode terminal T2 and the first electrode terminal T1, respectively. Therefore, the cylindrical battery 1 according to one embodiment of the present invention can simplify the electrical connection structure since both the positive and negative electrodes can be connected on one side when electrically connecting a plurality of cylindrical batteries 1. In addition, the cylindrical battery 1 according to one embodiment of the present invention has a structure in which most of the lower surface located opposite the open portion of the battery housing 20 can be used as an electrode terminal, and therefore a sufficient area can be secured for welding parts for electrical connection.

[0194] In one embodiment of the present invention, the sealing gasket G1 and the insulating gasket G2 may be made of a polymer resin having insulating properties and elasticity. For example, the sealing gasket G1 and the insulating gasket G2 may be made of polypropylene, polybutylene terephthalate, polyethylene fluoride, etc., but the present invention is not limited thereto.

[0195] Preferably, the cylindrical battery may be, for example, a cylindrical battery having a form factor ratio (defined as the diameter divided by the height of a cylindrical battery, i.e., the ratio of height (H) to diameter (Φ)) greater than about 0.4.

[0196] Here, the form factor refers to a series of numbers indicating the diameter and height of a cylindrical battery. A cylindrical battery according to an embodiment of the present invention may be, for example, 46110, 4875, 48110, 4880, 4680, etc. In the numbers indicating the form factor, the first two digits indicate the diameter of the cylindrical battery, and the remaining digits indicate the height of the cylindrical battery.

[0197] A battery according to one embodiment of the present invention may be a cylindrical battery that is generally cylindrical, with a diameter of about 46 mm, a height of about 110 mm, and a form factor ratio of 0.418.

[0198] Another embodiment of the battery may be a cylindrical battery that is generally cylindrical, with a diameter of about 48 mm, a height of about 75 mm, and a form factor ratio of 0.640.

[0199] In yet another embodiment, the battery may be a cylindrical battery that is generally cylindrical, with a diameter of about 48 mm, a height of about 110 mm, and a form factor ratio of 0.436.

[0200] In yet another embodiment, the battery may be a cylindrical battery that is generally cylindrical, with a diameter of about 48 mm, a height of about 80 mm, and a form factor ratio of 0.600.

[0201] In yet another embodiment, the battery may be a cylindrical battery that is generally cylindrical, with a diameter of about 46 mm, a height of about 80 mm, and a form factor ratio of 0.575.

[0202] Conventionally, batteries with a form factor ratio of about 0.4 or less have been used. That is, conventionally, for example, 1865 batteries, 2170 batteries, etc. have been used. In the case of an 1865 battery, its diameter is about 18 mm, its height is about 65 mm, and its form factor ratio is 0.277. In the case of a 2170 battery, its diameter is about 21 mm, its height is about 70 mm, and its form factor ratio is 0.300.

[0203] In the cylindrical battery 1 according to the embodiment of the present invention, the housing cover 40 does not have a polarity. Instead, since the first current collector 30 is connected to the inner peripheral surface of the battery housing 20, the outer surface of the bottom of the battery housing 20 has the opposite polarity to the terminal 50. Therefore, when connecting a plurality of cylindrical batteries 1 in series and / or parallel, wiring such as bus bar connection can be performed on one side of the cylindrical battery 1 using the outer surface of the bottom of the battery housing 20 and the terminal 50. Unlike the illustrated example, the cylindrical battery 1 is arranged such that the terminal 50 faces upward and the housing cover 40 faces downward, and electrical wiring can be performed using the terminal 50 and its surrounding flat surface. This can increase the number of cylindrical batteries that can be mounted in the same space, thereby improving energy density.

[0204] The cylindrical battery 1 according to the above-described embodiment is used to manufacture a battery pack.

[0205] FIG. 19 is a diagram illustrating a schematic configuration of a battery pack 3 according to an embodiment of the present invention.

[0206] 19, a battery pack 3 according to an embodiment of the present invention includes an assembly to which cylindrical batteries 1 are electrically connected, and a pack housing 2 that accommodates the assembly. The cylindrical battery 1 is a battery according to the embodiment described above. For convenience of illustration, components such as a bus bar for electrical connection of the cylindrical battery 1, a cooling unit, and external terminals are not shown.

[0207] The battery pack 3 is mounted on a vehicle. The vehicle may be, for example, an electric vehicle, a hybrid vehicle, or a plug-in hybrid vehicle. The vehicle may include a four-wheeled vehicle or a two-wheeled vehicle.

[0208] FIG. 20 is a diagram for explaining an automobile 5 including the battery pack 3 of FIG.

[0209] 20, an automobile 5 according to an embodiment of the present invention includes a battery pack 3 according to an embodiment of the present invention. The automobile 5 operates by receiving power from the battery pack 3 according to an embodiment of the present invention.

[0210] The above-described embodiments are illustrative in all respects and are not limiting, and the scope of the present invention is represented by the appended claims rather than the above detailed description. The meaning and scope of the claims, as well as all modifications and variations derived from the equivalent concept, are to be interpreted as being included in the scope of the present invention.

[0211] Although the present invention has been described with reference to the drawings illustrating the present invention, it is obvious that the present invention is not limited to the embodiments and drawings shown in the present specification, and that various modifications may be made by those skilled in the art within the scope of the technical concept of the present invention. Furthermore, even if the effects of the configuration of the present invention are not clearly stated in the description of the embodiments, it goes without saying that the effects that can be predicted by the corresponding configuration should also be recognized. [Explanation of symbols]

[0212] 1 Cylindrical battery 2 Pack Housing 3 Battery pack 4. Average Oxidation State 5. Automobiles 10 Electrode assembly 11 First electrode tab 12 2nd electrode tab 20 Battery Housing 21 Beading Section 22 Crimping section 30 Current collector (first current collector) 31 Loop 31a Part 1 31b Part 2 31c Part 3 31d Cutout 32 Tab joint 33 First housing joint 33a 1st contact part 33b 1st connection part 34 Second housing joint 34a 2nd contact part 34b 2nd connection part 40 Housing cover 41 Vent section 50 Terminals

Claims

1. an electrode assembly including a first electrode tab having an exposed uncoated portion at one end; a battery housing that accommodates the electrode assembly; and a current collector that contacts the first electrode tab and an inner circumferential surface of the battery housing to electrically connect the first electrode tab and the battery housing, The current collector is a loop-shaped portion that surrounds a central axis of the electrode assembly to define an opening area that exposes the first electrode tab; a tab coupling portion extending from an inner side of the loop portion adjacent to the opening region toward the opening region and coupled to the first electrode tab exposed from the opening region; a housing coupling portion extending from an outer side of the loop portion toward an inner peripheral surface of the battery housing and coupled to the battery housing.

2. The loop portion is a plurality of first portions spaced apart from one another along a circumferential direction at a first radial position of the exposed region of the first electrode tab; a plurality of second portions disposed between adjacent first portions in the circumferential direction at a second radial position that is outer than the first radial position; and 2. The cylindrical battery according to claim 1, further comprising a third portion connecting adjacent first portions in the circumferential direction and the second portions located between the first portions to define a space through which the tab connection portions extend.

3. The cylindrical battery according to claim 2 , wherein the tab connection portion extends from the second portion in a centripetal direction of the electrode assembly.

4. 4. The cylindrical battery of claim 3, wherein a gap is provided between the tab bond and the third portion.

5. An opening is provided on one side of the battery housing in the axial direction, The cylindrical battery according to claim 1 , wherein the housing coupling portion is coupled to an inner circumferential surface of the battery housing on which the opening is provided.

6. 6. The cylindrical battery according to claim 5, wherein the housing coupling portion is connected to an inner circumferential surface of a beading portion provided near the opening of the battery housing and pressed in a centripetal direction of the electrode assembly.

7. A housing cover that covers the opening, and a seal gasket interposed between the housing cover and the battery housing; The cylindrical battery according to claim 6 , wherein the housing joint portion is interposed and fixed between the seal gasket and the beading portion.

8. A winding hole is provided at the center of the electrode assembly, The cylindrical battery according to claim 1 , wherein a current collector hole facing the winding hole is provided at the center of the loop-shaped portion.

9. The cylindrical battery according to claim 1 , wherein the tab joint portion and the housing joint portion are connected through the loop portion.

10. 5. The cylindrical battery according to claim 1, wherein the loop portion has one or more cut-outs.

11. The housing joint portion is A contact portion coupled to an inner circumferential surface of the battery housing; and The cylindrical battery according to claim 1 , further comprising a connecting portion connecting between the contact portion and the loop portion.

12. The cylindrical battery according to claim 11 , wherein the contact portion extends along a circumferential direction of an inner circumferential surface of the battery housing.

13. The cylindrical battery according to claim 11 , wherein the coupling portion comprises one or more bent portions.

14. A battery pack comprising the cylindrical battery according to any one of claims 1 to 4.

15. A motor vehicle comprising the battery pack of claim 14.

16. A current collector electrically connecting an electrode assembly included in a cylindrical battery and a battery housing, a loop-shaped portion that surrounds a central axis of the electrode assembly to define an opening region that exposes an electrode tab made of a non-coated portion at one side end of the electrode assembly; a tab coupling portion extending from an inner side of the loop portion adjacent to the opening region toward the opening region and coupling with the electrode tab exposed from the opening region; a housing coupling portion extending from an outer side of the loop portion toward an inner peripheral surface of the battery housing and coupled to the battery housing.

17. The loop portion is a plurality of first portions spaced apart from one another along a circumferential direction at a first radial location of the exposed region of the electrode tab; a plurality of second portions disposed between adjacent first portions in the circumferential direction at a second radial position that is outer than the first radial position; and 17. The current collector according to claim 16, further comprising a third portion connecting adjacent first portions in the circumferential direction to second portions positioned between the first portions and defining a space through which the tab connection portion extends.

18. 18. The current collector of claim 17, wherein the first portion, the second portion, and the third portion are located on the same plane.

19. 20. The current collector of claim 17, wherein the tab bond extends from the second portion in a centripetal direction of the electrode assembly.

20. 20. The current collector of claim 19, wherein a gap is provided between the tab bond and the third portion.

21. The current collector according to claim 16 , wherein a current collector hole is provided at the center of the loop-shaped portion.

22. 21. The current collector according to claim 16, wherein the tab connection portion and the housing connection portion are connected through the loop portion.

23. 21. The current collector of claim 16, wherein the loop portion comprises one or more cut-outs.

24. The housing joint portion is A contact portion that contacts the battery housing; and The current collector according to claim 16 , further comprising a connecting portion connecting the contact portion and the loop portion.

25. 25. The current collector of claim 24, wherein the contact portion extends circumferentially about an inner periphery of the battery housing.

26. 25. The current collector of claim 24, wherein the coupling portion comprises one or more bends.

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