KR20230076745A - Electrode Assembly, Method and Apparatus for Manufacturing the same, Cylindrical battery including the Electrode Assembly, and Battery pack and Vehicle including the Cylindrical batter - Google Patents

Abstract

The present invention discloses an electrode assembly, a method and apparatus for manufacturing the same, a cylindrical battery including the electrode assembly, and a battery pack and an automobile including the same. The electrode assembly is an electrode assembly in which two electrodes and a separator interposed therebetween are wound around one axis, and include a non-coated portion exposed to the outside of the separator along an axial direction at the long side end of at least one of the electrodes, A winding turn portion of the uncoated portion is provided at one end of the electrode assembly, and the winding turn portion includes a cutting portion and a bending portion alternately disposed in a circumferential direction, and an axial height of the cutting portion is smaller than an axial height of the bending portion, The bent portion may include a plurality of uncoated flags arranged along a radial direction of the electrode assembly, and the plurality of uncoated flags may be bent along a radial direction of the electrode assembly while overlapping in an axial direction.

Description

Electrode Assembly, Method and Apparatus for Manufacturing the same, Cylindrical battery including the Electrode Assembly, and Battery pack and Vehicle including the Cylindrical batter}

The present invention relates to an electrode assembly, a method and apparatus for manufacturing the same, a cylindrical battery including the electrode assembly, a battery pack including the same, and an automobile.

Secondary batteries, which are highly applicable to each product group and have electrical characteristics such as high energy density, are used not only in portable devices but also in electric vehicles (EVs) or hybrid electric vehicles (HEVs) driven by an electrical driving source. It is universally applied.

These secondary batteries have not only the primary advantage of significantly reducing the use of fossil fuels, but also the advantage of not generating any by-products due to the use of energy, so they are attracting attention as a new energy source for eco-friendliness and energy efficiency improvement.

Currently, types of secondary batteries widely used include lithium ion batteries, lithium polymer batteries, nickel cadmium batteries, nickel hydride batteries, nickel zinc batteries, and the like. The operating voltage of such a unit secondary cell, that is, a unit battery is about 2.5V to 4.5V. Therefore, when a higher output voltage is required, a battery pack is formed by connecting a plurality of batteries in series. In addition, a battery pack is configured by connecting a plurality of batteries in parallel according to a charge/discharge capacity required for the battery pack. Accordingly, the number of batteries included in the battery pack and the type of electrical connection may be variously set according to a required output voltage and/or charge/discharge capacity.

On the other hand, as types of unit secondary batteries, cylindrical, prismatic and pouch type batteries are known. In the case of a cylindrical battery, a separator, which is an insulator, is interposed between a positive electrode and a negative electrode, and the electrode assembly in the form of a jelly roll is formed by winding the separator, and the electrode assembly is inserted into the battery housing to configure the battery. An electrode tab in the form of a strip may be connected to the non-coated portion of each of the positive and negative electrodes, and the electrode tab electrically connects the electrode assembly and an electrode terminal exposed to the outside. For reference, the positive terminal is a cap of a sealing body sealing the opening of the battery housing, and the negative terminal is the battery housing. However, according to the conventional cylindrical battery having such a structure, since the current is concentrated on the strip-shaped electrode tab coupled to the positive electrode uncoated portion and/or the negative electrode uncoated portion, resistance is high, a lot of heat is generated, and the current collection efficiency is poor. There was a problem.

For a small cylindrical battery with a 1865 or 2170 form factor, resistance and heat are not a big issue. However, when the form factor of the cylindrical battery is increased to apply it to an electric vehicle, a large amount of heat is generated around the electrode tab during a rapid charging process, causing the cylindrical battery to ignite.

In order to solve this problem, a cylindrical battery having a structure in which the positive and negative uncoated regions are located at the top and bottom of the jelly roll type electrode assembly, and a current collecting plate is welded to the uncoated region to improve the current collection efficiency. (a so-called tab-less cylindrical battery) was presented.

1 to 3 are views showing a manufacturing process of a tab-less cylindrical battery. 1 shows the structure of an electrode, FIG. 2 shows a winding process of an electrode, and FIG. 3 shows a process of welding a current collecting plate to a bent surface of a non-coated portion.

1 to 3, the positive electrode 10 and the negative electrode 11 have a structure in which an active material 21 is coated on a sheet-shaped current collector 20, and a long side of one side along a winding direction X. It includes an uncoated portion 22 .

The electrode assembly (A) is manufactured by sequentially stacking the positive electrode 10 and the negative electrode 11 together with two sheets of separator 12 as shown in FIG. 2 and then winding them in one direction (X). At this time, the uncoated portions of the positive electrode 10 and the negative electrode 11 are disposed in opposite directions relative to the direction of the short side of the separator 12 . The positions of the anode 10 and the cathode 11 may be reversed from those shown.

After the winding process, the uncoated portion 10a of the positive electrode 10 and the uncoated portion 11a of the negative electrode 11 are bent toward the core. After that, the current collector plates 30 and 31 are welded and coupled to the uncoated portions 10a and 11a, respectively.

Separate electrode tabs are not coupled to the positive uncoated portion 10a and the negative uncoated portion 11a, the current collecting plates 30 and 31 are connected to external electrode terminals, and the current path winds the electrode assembly A. Since it is formed with a large cross-sectional area along the axial direction (see arrow), it has the advantage of lowering the resistance of the battery. This is because resistance is inversely proportional to the cross-sectional area of the path through which current flows.

In the tab-less cylindrical battery, in order to improve the welding characteristics of the uncoated regions 10a and 11a and the current collecting plates 30 and 31, strong pressure is applied to the welding points of the uncoated regions 10a and 11a to make the uncoated regions as flat as possible ( 10a, 11a) should be bent.

When the uncoated portions 10a and 11a are bent, a jig that presses the uncoated portions 10a and 11a toward the core of the electrode assembly A is used.

4 shows the bent shape of the uncoated portions 10a and 11a by cutting a part of the bent portion in the longitudinal direction of the electrode assembly A when the uncoated portions 10a and 11b are bent toward the core along the radial direction using a jig. This is an enlarged picture.

As shown in FIG. 4 , the bent shapes of the uncoated portions 10a and 11a are not uniform, and it can be confirmed that the uncoated portions 10a and 11b are irregularly deformed and bent. In particular, the degree of deformation of the non-coated portions 10a and 11a increases toward the core of the electrode assembly A. The reason is that the stress applied by the jig increases as the uncoated portions 10a and 11a are located closer to the core side of the electrode assembly A.

If the uncoated portions 10a and 11a are irregularly bent, welding of the current collecting plates 30 and 31 is not easy because the bent surfaces are not flat. In addition, if the uncoated portions 10a and 11a are irregularly deformed below the bending surface, the stress resulting from the irregular deformation of the uncoated portions 10a and 11a affects the nearby separator, causing the separator to tear or the active material layer to break. An internal short circuit may be caused. If an internal short circuit occurs, the temperature of the cylindrical battery rises rapidly as an overcurrent flows, and as a result, the cylindrical battery may ignite or explode.

The present invention was invented under the background of the prior art as described above, and an electrode assembly manufacturing method and apparatus capable of making the bending shape of the uncoated portion uniform in bending the uncoated portion of a tab-less cylindrical battery, and an apparatus thereof. Its purpose is to provide an electrode assembly manufactured by the method and apparatus.

Another technical problem of the present invention is to provide a cylindrical battery including an electrode assembly manufactured by an improved method.

Another technical problem of the present invention is to provide an electrode assembly in which energy density is improved, resistance is reduced, and electrolyte impregnability can be improved.

Another technical problem of the present invention is to provide a cylindrical battery including an electrode assembly having an improved structure, a battery pack including the battery pack, and a vehicle including the battery pack.

The technical problem to be solved by the present invention is not limited to the above problem, and other problems not mentioned will be clearly understood by those skilled in the art from the description of the invention described below.

The electrode assembly according to the present invention for achieving the above technical problem is an electrode assembly in which a positive electrode, a negative electrode, and a separator interposed therebetween are wound around one axis to define a core and an outer circumferential surface, and at least one of the positive electrode and the negative electrode A long side end portion includes a plain portion exposed to the outside of the separator along the axial direction of the electrode assembly, and winding turns of the plain portion are provided at one end of the electrode assembly, and the winding turns are alternately disposed along the circumferential direction. a cut portion and a bent portion, wherein an axial height of the cut portion is smaller than an axial height of the bent portion, the bent portion includes a plurality of uncoated flags arranged along a radial direction of the electrode assembly, and the plurality of uncoated portions The flags may form a bent surface area along a radial direction of the electrode assembly while being overlapped along an axial direction.

The cutting part may include a first cutting surface substantially perpendicular to the axial direction. The first cutting surface may be an ultrasonic cutting surface.

An insulating coating layer is provided at the proximal end of the uncoated flag, an axial end of the insulating coating layer extends outwardly and is exposed to an axial end of the separator, and the first cutting surface is spaced apart from the axial end of the insulating coating layer. It can be.

When viewed in the axial direction, an axial end of the insulating coating layer and an axial end of the active material layer included in the positive electrode or the negative electrode may be exposed through the first cutting surface.

The plurality of uncoated flags may protrude along the axial direction from the first cutting surface.

The plurality of uncoated flags may be bent toward the core of the electrode assembly along a bending line spaced apart from the first cutting surface to form a bending surface area.

A bending length of the uncoated flag closest to the core of the electrode assembly may be equal to or smaller than a distance from the position of the uncoated flag to the core.

The first cutting surface may be spaced apart from the bending surface area.

The bent portion may include a second cutting surface extending along side edges of the plurality of uncoated flags. The second cutting surface may be an ultrasonic cutting surface.

The second cutting surface may be parallel to the axial direction.

The first cutting surface and the second cutting surface may cross each other perpendicularly.

The second cutting surface may be a flat surface.

The second cutting surface may be a rounded surface.

An eccentricity of a circular arc in which a virtual surface perpendicular to the axial direction and the rounded surface meet may be substantially 1.

The center of the imaginary circle including the arc and the center of the core of the electrode assembly may face each other based on the arc.

The circular arc may be substantially symmetric based on a straight line connecting the center of the imaginary circle including the circular arc and the center of the core of the electrode assembly.

The plurality of uncoated flags may have substantially the same width in a circumferential direction from a core side to an outer circumferential surface side of the electrode assembly.

A width of the plurality of uncoated flags in a circumferential direction may gradually increase or decrease while going from a core side to an outer circumferential surface side of the electrode assembly.

The cutting part may include first to nth cutting parts, and the first to nth cutting parts may radially extend with respect to the center of the core of the electrode assembly.

The first to nth cutting parts may be arranged rotationally symmetrically with respect to the center of the core of the electrode assembly.

The bent part may include first to nth bent parts, and the first to nth bent parts may radially extend with respect to the center of the core of the electrode assembly.

The first to nth bent parts may be arranged rotationally symmetrically with respect to the center of the core of the electrode assembly.

The bending surface area may include an area where three or more uncoated flags overlap along the axial direction.

An electrode assembly manufacturing method according to the present invention for achieving the above technical problem, (a) preparing a positive electrode and a negative electrode having a sheet shape and having a non-coated portion at a long side end; (b) the positive electrode, the negative electrode, and the separator are laminated at least once so that the separator is interposed between the positive electrode and the negative electrode, and the positive electrode uncoated portion and the negative electrode uncoated portion are exposed opposite to each other along a short side direction of the separator. Forming an electrode-separator layered body; (c) forming an electrode assembly by winding the electrode-separator laminate around one axis so that the turns of the positive electrode uncoated region and the turns of the negative electrode uncoated region are exposed in opposite directions along an axial direction; and (d) cutting at least one of the winding turns of the positive electrode uncoated portion and the winding turns of the cathode uncoated portion so that at least one bending target region remains (remains) in a protruding shape along the axial direction. forming a plurality of uncoated flags in the bending target region by cutting; and (e) forming a bending surface area by bending the plurality of uncoated flags included in the bending target area along a radial direction of the electrode assembly.

The step (d) may include a first cutting step of cutting an edge of the bending target region along the axial direction of the electrode assembly; and a second cutting step of cutting a peripheral area of the bending target area perpendicular to the axial direction so that the bending target area remains (remains) in a protruding shape along the axial direction.

In the first cutting step, an edge of the bending target region may be cut using a vertical cutter that vibrates ultrasonically in an axial direction of the electrode assembly.

There are a plurality of cutting lines for the edge of the bending target region, and when viewed from the axial direction of the electrode assembly, the plurality of cutting lines may form pairs of two and radially extend from the center of the core of the electrode assembly.

A plurality of cutting lines may be formed at an edge of the bending target region, and when viewed in an axial direction of the electrode assembly, each of the plurality of cutting lines may have an arc shape curved toward a core center of the electrode assembly.

In the second cutting step, by using a horizontal cutter that vibrates ultrasonically perpendicularly to the axial direction of the electrode assembly, the periphery of the bending target region remains (remains) in a protruding shape along the axial direction. A region may be cut perpendicular to the axial direction.

In the second cutting step, by using a horizontal cutter that rotates in a plane perpendicular to the axial direction of the electrode assembly, the bending target area remains (remains) in a protruding shape along the axial direction. A peripheral area may be cut perpendicularly to the axial direction.

In the second cutting step, by using a horizontal cutter that rotates in a plane perpendicular to the axial direction of the electrode assembly and vibrates ultrasonically along the plane, the bending target region remains in a protruding shape along the axial direction. (To remain) a peripheral area of the bending target area may be cut perpendicularly to the axial direction.

In the step (e), the plurality of uncoated flags may be bent so that an area where at least three or more uncoated flags overlap in the axial direction is included in the bending surface area.

The ultrasonic cutting device according to the present invention for achieving the above technical problem is exposed at one end of an electrode assembly wound around one axis of an anode and a cathode, and a separator interposed therebetween, including a non-coated portion at the end of the long side. An ultrasonic cutting device for cutting and processing winding turns of the uncoated portion, wherein the edges of the plurality of bending target regions disposed along the circumferential direction of the electrode assembly are ultrasonically cut along the axial direction to form a plurality of uncoated flags within the bending target region. vertical cutter; and a horizontal cutter that ultrasonically cuts peripheral regions of the plurality of bending target regions perpendicular to the axial direction to protrude the plurality of uncoated flags from the ultrasonic cutting surface along the axial direction.

The vertical cutter, the cutter body; and a plurality of cutter knives coupled to the cover sea, wherein the plurality of cutter knives may be arranged to correspond to edges of the plurality of bending target regions.

The horizontal cutter, the cutter body; and a cutter knife coupled to the cutter body, wherein the cutter knife is coupled to the cutter body so as to lie on a cutting plane perpendicular to the axial direction, and a winding turn between adjacent bending target regions in the circumferential direction. It may have a shape corresponding to the region.

A winding turn area between the bent surface areas adjacent in the circumferential direction includes a portion curved toward the core of the electrode assembly, and the cutter knife has a disk shape having a radius substantially equal to a radius of curvature of the curved portion. may be a rotating knife of

A cylindrical battery according to the present invention for achieving the above technical problem is (a) an electrode assembly in which a positive electrode and a negative electrode and a separator interposed therebetween are wound around one axis to define a core and an outer circumferential surface, and among the positive electrode and the negative electrode At least one includes a non-coated portion exposed to the outside of the separator along an axial direction of the electrode assembly at a long side end, and includes a winding turn portion of the uncoated portion at one end of the electrode assembly, and the winding portion is formed along a circumferential direction. A cut portion and a bent portion are alternately disposed, an axial height of the cut portion is smaller than an axial height of the bent portion, the bent portion includes a plurality of uncoated flags arranged along a radial direction of the electrode assembly, and the plurality of uncoated flags are arranged. an electrode assembly, wherein the uncoated flag of the overlaps along the axial direction and forms a bending surface area along the radial direction of the electrode assembly; (b) a battery housing including an open end and a closed part opposite thereto, in which the electrode assembly is accommodated through the open end, and electrically connected to the negative electrode; (c) a sealing body sealing the open end of the battery housing; (d) a terminal electrically connected to the anode and having a surface exposed to the outside; and (e) a current collecting plate welded to the bent surface area and electrically connected to either the battery housing or the terminal.

The terminal is a rivet terminal installed in a through hole formed in the closed portion of the battery housing, and an insulating gasket may be interposed between the rivet terminal and the through hole.

The rivet terminal may be welded to the current collecting plate.

The current collecting plate may include a support portion including a hole; at least one leg portion extending in a radial direction from the support portion and welded to the bent surface area; a connecting portion provided inside the hole; and a bridge part connecting the support part and the connection part.

The cylindrical battery may further include a crimping portion formed by bending an open end of the battery housing toward the core. In addition, the sealing body includes a cap covering the open end of the battery housing, and a sealing gasket interposed between the cap and the open end, and the crimping unit presses the sealing gasket toward the edge of the cap. can

The cylindrical battery further includes a beading portion in a region adjacent to the open end of the battery housing, and at least a portion of an edge of the current collecting plate is interposed between an inner surface of the beading portion and the sealing gasket to engage the inner surface of the beading portion. It can be.

At least a portion of an edge of the current collecting plate may be welded to an inner surface of the beading part.

The current collecting plate may include a support part; at least one leg portion extending in a radial direction from the support portion and welded to the bent surface area; and a housing connection part extending from the support part or the leg part toward the beading part and coupled to an inner surface of the beading part.

The cap corresponds to the terminal, and the current collecting plate includes: a support part; at least one leg portion extending outwardly from the support portion and welded to the bending surface area; and a lead portion extending from the support portion or the leg portion and coupled to the cap.

The above technical problem can also be achieved by a battery pack including a plurality of the above-described cylindrical batteries and a vehicle including the battery pack.

According to one aspect of the present invention, the bending target region of the uncoated region having a protruding shape along the axial direction of the electrode assembly is formed in a pattern extending along the bending direction, and the uncoated region flags of the bending target region are bent to bend the uncoated region. It is possible to improve the flatness of the surface, and it is possible to alleviate a phenomenon in which the uncoated portion is irregularly bent at the bottom of the bent surface.

According to another aspect of the present invention, by cutting a significant portion of the winding turn of the non-coated region in the peripheral area of the bending target area at the axial end of the electrode assembly to provide a passage through which the electrolyte can rapidly penetrate into the active material layer, the electrolyte impregnation is improved. can be improved

According to another aspect of the present invention, since the axial height of the electrode assembly can be reduced by cutting and bending the winding turn of the uncoated region, the energy density of the cylindrical battery can be increased accordingly.

According to another aspect of the present invention, in the process of cutting the winding turn of the uncoated portion, a plurality of uncoated flags formed in the bending target region are bent along the radial direction of the electrode assembly, resulting in a bending surface in which the uncoated flags are overlapped in several layers. After forming the region, resistance of the cylindrical battery may be reduced by welding a current collector plate to the region.

According to another aspect of the present invention, by providing an ultrasonic cutting device including a vertical cutter and a horizontal cutter, the winding turn portion of the uncoated portion can be easily cut so that the bending target region remains protruded in the axial direction of the electrode assembly. .

According to another aspect of the present invention, productivity and manufacturing cost of the electrode assembly can be reduced by providing a method for easily cutting the turn portion of the uncoated portion so that the bending target region remains protruded in the axial direction of the electrode assembly. can

According to another aspect of the present invention, by providing a high-capacity battery pack manufactured using cylindrical batteries having high energy density and low resistance, and a vehicle including the battery pack, it is possible to improve the safety of rapid charging and the efficiency of energy use.

In addition, the present invention may have various other effects, which will be described in each embodiment, or descriptions of effects that can be easily inferred by those skilled in the art will be omitted.

The following drawings attached to this specification illustrate preferred embodiments of the present invention, and together with the detailed description of the present invention serve to further understand the technical idea of the present invention, the present invention is the details described in such drawings should not be construed as limited to
1 is a plan view showing the structure of an electrode used in manufacturing a conventional tab-less cylindrical battery.
2 is a view showing an electrode winding process of a conventional tab-less cylindrical battery.
3 shows a process of welding a current collector plate to a curved surface of a non-coated portion in a conventional tab-less cylindrical battery.
4 is an enlarged photograph of a bending structure of an uncoated portion in a cross section of an electrode assembly according to the prior art.
5 is a plan view showing the structure of an electrode according to an embodiment of the present invention.
6A is a cross-sectional view of a jelly roll-type electrode assembly in which an electrode according to an embodiment of the present invention is applied to an anode and a cathode, cut along an axial direction (Y).
6B is a partial perspective view showing an upper structure of an electrode assembly according to an embodiment of the present invention.
6C is a partial cross-sectional view of the bending target region of the electrode assembly according to the embodiment of the present invention cut along the axial direction (Y).
6D is an upper plan view illustrating a cutting structure of a winding turn portion provided on an upper portion of an electrode assembly according to another embodiment of the present invention.
7 is a plan view of a vertical cutter used when cutting a winding turn along an axial direction (Y) according to an embodiment of the present invention.
8 is a cross-sectional view of a vertical cutter used when cutting a winding turn along an axial direction (Y) according to an embodiment of the present invention.
9 is a configuration diagram schematically showing the configuration of an ultrasonic cutting device according to an embodiment of the present invention.
10 to 12 are plan views of vertical cutters according to various modified examples of the present invention.
13 is a plan view of a horizontal cutter used when cutting a winding turn perpendicular to the axial direction (Y) according to an embodiment of the present invention.
14 is a cross-sectional view of a horizontal cutter used when cutting a winding turn perpendicularly to the axial direction (Y) according to an embodiment of the present invention.
15 is a plan view of a horizontal cutter including a rotary knife according to another embodiment of the present invention.
16 is a cross-sectional view of a horizontal cutter including a rotating knife according to another embodiment of the present invention.
17 is a plan view showing a state after forming a cutting line on a winding turn of an electrode assembly using a vertical cutter according to an embodiment of the present invention.
18 is a view showing a process of cutting a winding turn portion in a plane (XZ plane) perpendicular to the axial direction (Y) of the electrode assembly by using a horizontal cutter according to an embodiment of the present invention.
19 is a plan view showing a state after forming a cutting line on a winding turn of an electrode assembly using a vertical cutter according to another embodiment of the present invention.
20 is a view showing a process of cutting a winding turn portion in a plane (XZ plane) perpendicular to the axial direction (Y) of the electrode assembly by using a horizontal cutter including a rotary knife according to an embodiment of the present invention.
21 to 24 are top plan views showing the arrangement structure of the bending target area after the winding turn is cut according to an embodiment of the present invention.
25A is a cross-sectional view of a cylindrical battery cut along an axial direction Y according to an embodiment of the present invention.
25B is a plan view showing the structure of a first current collecting plate according to an embodiment of the present invention.
25C is a plan view showing the structure of a second current collecting plate according to an embodiment of the present invention.
26A is a cross-sectional view of a cylindrical battery according to another embodiment of the present invention taken along an axial direction (Y).
26B is a plan view showing the structure of a first current collecting plate according to another embodiment of the present invention.
26C is a perspective view showing the structure of a second current collecting plate according to another embodiment of the present invention.
27 is a diagram schematically illustrating the configuration of a battery pack according to an embodiment of the present invention.
28 is a diagram schematically illustrating a vehicle including a battery pack according to an embodiment of the present invention.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. Prior to this, the terms or words used in this specification and claims should not be construed as being limited to ordinary or dictionary meanings, and the inventors appropriately use the concept of terms in order to best explain their invention. It should be interpreted as a meaning and concept consistent with the technical idea of the present invention based on the principle that it can be defined.

Therefore, the embodiments described in this specification and the configurations shown in the drawings are only one of the most preferred embodiments of the present invention and do not represent all of the technical ideas of the present invention, so various alternatives can be made at the time of this application. It should be understood that there may be equivalents and variations.

In addition, in order to aid understanding of the present invention, the accompanying drawings may not be drawn to an actual scale, but the dimensions of some components may be exaggerated. In addition, the same reference numbers may be assigned to the same components in different embodiments.

Although first, second, etc. are used to describe various components, these components are not limited by these terms, of course. These terms are only used to distinguish one component from another component, and unless otherwise stated, the first component may be the second component, of course.

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

Hereinafter, the arrangement of an arbitrary element on the "upper (or lower)" or "upper (or lower)" of a component means that an arbitrary element is placed in contact with the upper (or lower) surface of the component. In addition, it may mean that other components may be interposed between the component and any component disposed on (or under) the component.

In addition, when a component is described as "connected", "coupled" or "connected" to another component, the components may be directly connected or connected to each other, but other components may be "interposed" between each component. ", or each component may be "connected", "coupled" or "connected" through other components.

Singular expressions used herein include plural expressions unless the context clearly dictates otherwise. In this application, terms such as "consisting of" or "comprising" should not be construed as necessarily including all of the various components or steps described in the specification, and some of the components or some of the steps It should be construed that it may not be included, or may further include additional components or steps.

Also, singular expressions used in this specification include plural expressions unless the context clearly indicates otherwise. In this application, terms such as "consisting of" or "comprising" should not be construed as necessarily including all of the various components or steps described in the specification, and some of the components or some of the steps It should be construed that it may not be included, or may further include additional components or steps.

Throughout the specification, when it says "A and/or B", it means A, B or A and B, unless otherwise specified, and when it says "C to D", it means no particular contrary description As long as there is no, it means C or more and D or less.

For convenience of description, in this specification, a direction along the longitudinal direction of the winding shaft of the electrode assembly that is wound in the form of a jelly roll is referred to as an axial direction (Y). A direction surrounding the winding axis is referred to as a circumferential direction or a circumferential direction (X). Further, a direction closer to or away from the winding axis is referred to as a radial direction or a radial direction (Z). Among these, a direction closer to the winding axis is referred to as a centripetal direction, and a direction away from the winding axis is referred to as a centrifugal direction.

First, an electrode assembly according to an embodiment of the present invention will be described. The electrode assembly is a jelly roll type electrode assembly having a structure in which a positive electrode and a negative electrode having a sheet shape and a separator interposed therebetween are wound in one direction.

Preferably, at least one of the positive electrode and the negative electrode includes an uncoated portion not coated with an active material at an end of a long side in a winding direction. At least a part of the uncoated portion is used as an electrode tab by itself.

5 is a plan view showing the structure of an electrode 40 according to an embodiment of the present invention.

Referring to FIG. 5 , the electrode 40 includes a current collector 41 made of metal foil and an active material layer 42 . The metal foil is made of a conductive metal. The metal foil may be aluminum or copper, and is appropriately selected according to the polarity of the electrode 40 . The active material layer 42 is formed on at least one surface of the current collector 41 and includes a non-coated portion 43 at an end of a long side in the winding direction X. The uncoated portion 43 is a region not coated with an active material. An insulating coating layer 44 may be formed at a boundary between the active material layer 42 and the uncoated portion 43 . At least a portion of the insulating coating layer 44 overlaps the boundary between the active material layer 42 and the uncoated portion 43 . The insulating coating layer 44 may include a polymer resin and may include an inorganic filler such as SiO ₂ and Al ₂ O ₃ . The polymer resin may have a porous structure. The polymer resin is not particularly limited as long as it is an insulating material. The polymer resin may be polyolefin, polyimide, polyethylene terephthalate, polybutylene fluoride, etc., but the present invention is not limited thereto.

Preferably, a portion of the uncoated portion 43 adjacent to the core side may be cut through a notching process. In this case, even if the uncoated portion 43 is bent toward the core, the core of the electrode assembly is not blocked by the bent portion of the uncoated portion 43 . For reference, the core is provided with a cavity formed when a bobbin used for winding the electrode assembly is removed. The cavity may be used as an electrolyte injection passage or a passage for inserting a welding jig. In the figure, a dashed-dotted line indicates the lowest position at which the uncoated portion 43 is bent. The uncoated portion 43 is bent at a position higher than the one-dotted chain line.

The cut portion B of the uncoated portion 43 forms a plurality of winding turns in the radial direction when the electrode 40 is wound. The plurality of winding turns have a predetermined width in a radial direction. Preferably, the width d of the cutting portion B and the bending length h of the uncoated portion 43 may be adjusted such that the predetermined width is equal to or greater than the bending length h of the uncoated portion 43. . Then, even if the uncoated portion 43 is bent, the core of the electrode assembly is not blocked.

In order to prevent the active material layer 42 and/or the insulating coating layer 44 from being damaged when the cutting portion B of the uncoated portion 43 is formed, a gap G is formed between the cutting line and the insulating coating layer 44. It is desirable to put The gap G is preferably 0.2 mm to 4 mm. When the gap G is adjusted to the corresponding numerical range, it is possible to prevent the active material layer 42 and/or the insulating coating layer 44 from being damaged due to cutting tolerance when the uncoated portion 43 is cut.

In a specific example, when the electrode 40 is used to manufacture an electrode assembly of a cylindrical battery having a form factor of 4680, the width d of the uncoated region cutting portion B is 180 mm to 350 mm depending on the diameter of the electrode assembly core. can be set

Meanwhile, when the core of the electrode assembly is not used in an electrolyte injection process, a welding process, or the like, the cutting portion B of the uncoated portion 43 may not be formed.

The electrode 40 of the above-described embodiment may be applied to an anode and/or a cathode included in a jelly roll type electrode assembly. In addition, when the electrode structure of the embodiment is applied to one of the anode and the cathode, the conventional electrode structure (FIG. 1) may be applied to the other. In addition, electrode structures applied to the anode and the cathode may not be identical to each other and may be different.

In the present invention, the positive electrode active material coated on the positive electrode and the negative electrode active material coated on the negative electrode may be used without limitation as long as they are known in the art.

In one example, the cathode active material has the general formula A[A _x M _y ]O _2+z (A includes at least one element of Li, Na, and K; M is Ni, Co, Mn, Ca, Mg, Al, including at least one element selected from 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; the stoichiometric coefficients x, y and z are selected such that the compound remains electrically neutral).

In another example, the cathode active material is an alkali metal compound disclosed in US6,677,082, US6,680,143, etc. xLiM ¹ O ₂ -(1-x)Li ₂ M ² O ₃ (M ¹ is at least one element having an average oxidation state of 3). contains; M ² contains at least one element having an average oxidation state of 4; 0≤x≤1).

In another example, the cathode active material has the general formula Li _a M ¹ _x Fe _1x M ² _y P _1y M ³ _z O _4z (M ¹ is Ti, Si, Mn, Co, Fe, V, Cr, Mo, Ni, contains at least one element selected from Nd, Al, Mg, and Al; M ² is Ti, Si, Mn, Co, Fe, V, Cr, Mo, Ni, Nd, Al, Mg, Al, As, Sb, Si , Ge, V and at least one element selected from S; M ³ contains a halogen group element optionally including F; 0 < a ≤ 2, 0 ≤ x ≤ 1, 0 ≤ y < 1, 0 ≤ z <1; the stoichiometric coefficients a, x, y and z are chosen such that the compound remains electrically neutral), or Li ₃ M ₂ (PO ₄ ) ₃ [M is Ti, Si, Mn, Fe, Co, V, including at least one element selected from Cr, Mo, Ni, Al, Mg, and Al].

Preferably, the cathode active material may include primary particles and/or secondary particles in which the primary particles are aggregated.

In one example, the negative electrode active material may use a carbon material, lithium metal or a lithium metal compound, silicon or a silicon compound, tin or a tin compound, or the like. Metal oxides such as TiO ₂ and SnO ₂ having a potential of less than 2 V can also be used as an anode active material. As the carbon material, both low crystalline carbon and high crystalline carbon may be used.

The separator is a porous polymer film, for example, a porous polymer film made of polyolefin-based polymers such as ethylene homopolymer, propylene homopolymer, ethylene/butene copolymer, ethylene/hexene copolymer, and ethylene/methacrylate copolymer. Alternatively, they may be laminated and used. As another example, the separator may use a conventional porous nonwoven fabric, for example, a nonwoven fabric made of high melting point glass fiber, polyethylene terephthalate fiber, or the like.

At least one surface of the separator may include a coating layer of inorganic particles. It is also possible that the separation membrane itself is made of a coating layer of inorganic particles. Particles constituting the coating layer may have a structure combined with a binder so that an interstitial volume exists between adjacent particles.

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 are Pb(Zr,Ti)O ₃ (PZT), Pb _1-x La _x Zr _1-y Ti _y O ₃ (PLZT), PB(Mg ₃ Nb _2/3 )O ₃ -PbTiO ₃ (PMN-PT), BaTiO ₃ , hafnia(HfO ₂ ), SrTiO ₃ , TiO ₂ , Al ₂ O ₃ , ZrO ₂ , SnO ₂ , CeO ₂ , MgO, CaO, ZnO and Y ₂ O ₃ It may include at least one or more materials selected from the group consisting of.

The electrode 40 according to the embodiment of the present invention may be applied to the positive and negative electrodes of the jelly roll type electrode assembly.

6A is a cross-sectional view of a jelly roll-type electrode assembly 50 in which electrodes 40 according to an embodiment of the present invention are applied to positive and negative electrodes cut along the axial direction Y, and FIG. 6B is a cross-sectional view of the electrode assembly 50 6C is a partial perspective view showing the upper structure, and FIG. 6C is an axial direction (Y) showing a state in which a plurality of uncoated flags 48c included in the bending target region of the electrode assembly 50 are bent along the radial direction (Z). It is a partial cross-section.

Referring to FIG. 6A , the electrode assembly 50 may be manufactured by the winding method described with reference to FIG. 2 . The uncoated portion 41 protruding upward of the electrode assembly 50 extends from the anode 43 . The uncoated portion 42 protruding from the lower portion of the electrode assembly 50 extends from the negative electrode 44 .

An upper portion of the electrode assembly 50 is provided with a winding turn portion 48 formed by winding the uncoated portion 41 of the positive electrode 43 . Similarly, a winding turn portion 49 formed by winding the uncoated portion 42 of the negative electrode 44 is provided at the lower portion of the electrode assembly 50 . The winding turns 48 and 49 are exposed to the outside of the separator 45 along the axial direction Y.

The separator 45 is interposed between the anode 43 and the cathode 44 . A length of the active material coated region of the positive electrode 43 in the Y-axis direction may be smaller than a length of the active material coated region of the negative electrode 44 in the Y-axis direction. Accordingly, the active material coated region of the negative electrode 44 may extend longer along the Y-axis direction than the active material coated region of the positive electrode 43 .

Preferably, the insulating coating layer 47 formed on the boundary between the active material regions of the positive electrode 43 and the negative electrode 44 and the uncoated portion may extend to the end of the separator 45 or may be exposed from the end to the outside. When the insulating coating layer 47 is exposed to the outside of the separator 45, it may serve to support a bending point when the uncoated portions 41 and 42 are bent. When the bending point is supported, stress applied to the active material layer and the separator 45 when the uncoated portions 41 and 42 are bent is relieved. In addition, the insulating coating layer 47 can prevent the anode 43 and the cathode 44 from contacting each other to cause a short circuit.

The positive electrode 43 includes a current collector and an active material coating layer formed on at least one surface thereof, and the current collector (uncoated portion 41) may have a thickness of 180 um to 220 um. The negative electrode 44 includes a current collector and an active material coating layer formed on at least one surface thereof, and the current collector (uncoated portion 42) may have a thickness of 140 um to 180 um. The separator 45 is interposed between the anode 43 and the cathode 44 and may have a thickness of 8um to 18um.

In the winding structure of the anode 43, the distance between the uncoated portions 41 located in the winding turns adjacent in the radial direction may be 350 um to 380 um. In addition, in the winding structure of the cathode 44, the distance between the uncoated portions 42 located in the winding turns adjacent in the radial direction may be 350 to 380 um.

In the electrode assembly 50, the number of winding turns of the positive electrode 43 varies depending on the form factor of the cylindrical battery, and may be 48 to 56. The number of winding turns of the negative electrode 44 also depends on the form factor of the cylindrical battery and may be 48 to 56.

The uncoated portions 41 and 42 are longer than the uncoated portions applied to the design of the small cylindrical battery. Preferably, the uncoated portions 41 and 42 may be 6 mm or more, optionally 7 mm or more, optionally 8 mm or more, optionally 9 mm or more, optionally 10 mm or more, optionally 11 mm or more, and optionally 12 mm or more.

Referring to FIG. 6B , the winding turn portion 48 of the anode 43 includes cut portions 48a and bent portions 48b alternately disposed along the circumferential direction X. The height of the cut portion 48a in the axial direction (Y) is smaller than the height of the bent portion 48b in the axial direction (Y). The region near the core C of the electrode assembly 50 does not include the bent portion 48b. This is because the uncoated portion on the core side of the anode 43 is low in height (see Fig. 5).

The bent portion 48b includes a plurality of uncoated flags 48c arranged along the radial direction Z of the electrode assembly 50 . The plurality of uncoated flags 48c have substantially the same width in the circumferential direction from the core side to the outer circumferential surface side of the electrode assembly 50 . Alternatively, the width of the plurality of uncoated flags 48c in the circumferential direction may gradually increase from the core side of the electrode assembly 50 to the outer circumferential surface side. In this case, the bent portion 48b may have a substantially fan-shaped shape when viewed in the axial direction Y.

The cutting portion 48a may include first through n-th cutting portions. The first to nth cutting parts may be arranged rotationally symmetrically with respect to the center of the core C of the electrode assembly 50 . Similarly, the bent portion 48b may include first through nth bent portions. In addition, the first to nth bent parts may be arranged rotationally symmetrically with respect to the center of the core C of the electrode assembly C. Rotational symmetry refers to symmetry in which the structures are consistent when the electrode assembly 50 is rotated at a predetermined angle along the winding direction.

In the embodiment, n is 4 because the number of cut portions 48a and bent portions 48b is four. In addition, the four cut parts 48a and the four bent parts 48b are 90 degrees rotationally symmetric with respect to the center of the core C of the electrode assembly 50 .

Meanwhile, n may decrease or increase to 2, 3, 5, 6, 9, and the like. Therefore, the rotational symmetry angle can be changed to 180 degrees, 120 degrees, 75 degrees, 60 degrees, 40 degrees, etc. according to the value of n.

Referring to FIG. 6C , the plurality of uncoated flags 48c overlap along the axial direction Y and are bent along the radial direction Z of the electrode assembly 50 to form a flat bending surface area F. there is.

Even if the plurality of uncoated flags 48c are bent, the core C of the electrode assembly 50 is not shielded. To this end, the bending length of the uncoated flag 48c closest to the core C may be equal to or smaller than the distance from the point where the corresponding uncoated flag 48c is located to the core C.

The bending surface area F may be used as a welding area of the current collecting plate. The bending surface area F includes an area where the uncoated flags 48c are overlapped in several layers along the axial direction Y in order to achieve sufficient welding strength.

Referring to FIGS. 6A and 6B , the cutting portion 48a may include a first cutting surface 51 substantially perpendicular to the axial direction Y. The first cutting surface 51 may be an ultrasonic cutting surface formed by cutting the winding turn portion 48 provided on the upper portion of the electrode assembly 50 perpendicularly to the axial direction Y by an ultrasonic cutting device.

An insulating coating layer 47 is provided at the proximal end of the plurality of plain flags 48c, and an axial direction (Y) end of the insulating coating layer 47 extends outward from the axial direction (Y) end of the separator 45 and is exposed. It can be. The first cutting surface 51 may be spaced apart from the end of the insulating coating layer 47 in the axial direction (Y) by an amount corresponding to a cutting tolerance. An axial end of the insulating coating layer 47 in the axial direction (Y) and an axial end of the active material layer included in the negative electrode 44 may be exposed through the first cutting surface 51 when viewed in the axial direction (Y). Therefore, the electrolyte directly contacts the axial end of the active material layer included in the negative electrode 44 and the axial (Y) end of the insulating coating layer 47 through the first cutting surface 51, thereby improving impregnation (speed and uniformity). ) can be significantly improved.

Referring to FIG. 6C , the plurality of uncoated flags 48c may protrude upward from the first cutting surface 51 along the axial direction Y. The plurality of uncoated flags 48c included in the bent portion 48b are bent toward the core C of the electrode assembly 50 along a bending line spaced apart from the first cutting surface 51, so that the bending surface area ( F) form The first cutting surface 51 may be spaced apart from the bending surface area F in the axial direction Y due to the position of the bending line.

Referring to FIG. 6B , the bent portion 48b includes second cutting surfaces 52 extending along the sides of the plurality of uncoated flags 48c. The second cutting surface 52 may be an ultrasonic cutting surface formed by cutting the winding turn portion 48 provided on the upper portion of the electrode assembly 50 along the axial direction by an ultrasonic cutting device. Thus, the second cutting surface 52 has a state parallel to the axial direction (Y). In addition, the second cutting surface 52 is a flat surface, and perpendicularly intersects the first cutting surface 51 with each other.

In the present invention, the cutting structure of the winding turn portion 48 provided on the upper part of the electrode assembly 50 can be modified in various ways.

FIG. 6D is an upper plan view showing another cutting structure of the winding turn portion 48 provided on the upper part of the electrode assembly 50. Referring to FIG.

Referring to FIG. 6D , the second cutting surface 52 perpendicularly intersects the first cutting surface 51, but may have a round shape. The configuration of the ultrasonic cutting device for forming the second cutting surface 52 having a round surface shape will be described later.

The eccentricity of the arc (R _arc ) where the second cutting surface 52 meets an imaginary plane perpendicular to the axial direction (Y) may be substantially 1. That is, the arc (R _arc ) may correspond to the arc of the imaginary circle (R) indicated by a dashed-dotted line. The center of the core (O ₁ ) of the electrode assembly 50 and the center (O ₂ ) of the imaginary circle (R) may face each other based on the arc (R _arc ). In addition, the arc R arc may be substantially symmetric based on a straight line connecting the center O ₁ of the core of the electrode assembly 50 and the center O ₂ of the imaginary _circle R.

When the second cutting surface 52 is formed of a round surface, the circumferential width of the uncoated flag 48c gradually decreases from the core side of the electrode assembly 50 to the outer circumferential side. In this case, since the bending surface area F is expanded, there is an advantage in securing a wide welding area of the current collecting plate.

The structure of the winding turn portion 48 described with reference to FIGS. 6A to 6D may be substantially equally applied to the winding turn portion 49 of the non-coated portion of the cathode 44 exposed at the bottom of the electrode assembly 50 . Therefore, description of the embodiments of the winding turn portion 49 of the uncoated portion of the negative electrode 44 will be omitted.

The structure of the winding turns 48 and 49 provided on the upper and lower portions of the electrode assembly 50 is to cut the winding turns 48 and 49 along the axial direction Y of the electrode assembly 50, and then to the axial direction ( It may be formed by cutting along a direction (Z) perpendicular to Y). Of course, it is self-evident that the order of cutting can be reversed.

Hereinafter, cutting along the axial direction (Y) is referred to as 'vertical cutting', and cutting in the axial direction (Y) and the vertical direction (Z) is referred to as 'horizontal cutting'.

7 and 8 are views showing the structure of the vertical cutter 60 used for vertical cutting of the winding turns 48 and 49 according to an embodiment of the present invention, Figure 7 is a plan view of the vertical cutter 60 8 is a cross-sectional view of the vertical cutter 60 along line A-A' in FIG. 7 .

7 and 8, the vertical cutter 60 includes a cutter body 61 and a plurality of cutter knives 62, and a plurality of cutter knives 62 are inserted into and fixed to the cutter body 61. Grooves may be provided. Preferably, the cutter body 61 may be coupled to the horn 63 of the ultrasonic cutting device. The ultrasonic cutting device will be described later.

Preferably, the cutter body 61 is made of a metal material, such as aluminum alloy, titanium alloy, or carbon steel. The cutter knife 62 is made of a metal material, such as carbon steel, alloy iron, high-speed steel, cast alloy, cermet, cubic boron nitride, ceramic, diamond, etc. It is done.

Lower ends of the plurality of cutter knives 62 may be embedded in the cutter body 61 . Alternatively, the lower end of the cutter knife 62 may be inserted into a groove formed in the cutter body 61 and then welded to the cutter body 61 .

Each of the cutter knives 62 has a strip shape extending outward from the center of the cutter body 61 and standing upright with respect to the surface of the cutter body 61 .

The plurality of cutter knives 62 may be arranged to correspond to the edges of the plurality of bending target regions (bend parts).

Preferably, the plurality of cutter knives 62 may form pairs of two and extend outwardly in parallel from the center of the cutter body 61 . An area between the two cutter knives 62 extending in parallel is an area corresponding to the bending target area (bending portion) of the winding turn portion.

The plurality of cutter knives 62 are paired by two and extend radially with respect to the center of the cutter body 61, but the angles between the pairs of cutter knives 62 may be substantially the same.

In one example, the number of cutter knives 62 may total eight. In this case, pairs of radially extending cutter knives 62 form an angle of 90 degrees to each other. As will be described later, the radially extending shape of the pair of cutter knives 62 can be variously modified.

The vertical cutter 60 ultrasonically cuts the edges of a plurality of bending target regions (bend parts) arranged along the circumferential direction along the axial direction (Y). Then, as shown in FIG. 6B, while the second cutting surface 52 parallel to the axial direction (Y) is formed along the edge of the plurality of bending target areas (bend parts), within the bending target areas (bend parts). A plurality of non-uniform flags 48c may be defined.

The vertical cutter 60 may be included in the ultrasonic cutting device.

9 is a configuration diagram schematically showing the configuration of an ultrasonic cutting device 70 according to an embodiment of the present invention.

Referring to FIG. 9 , the ultrasonic cutting device 70 according to the embodiment may include a converter 71, a booster 72, a horn 73, and a cutter 74.

The converter 71 generates ultrasonic vibrations. The converter 71 may include a ceramic vibrator to generate ultrasonic waves. The booster 72 amplifies the ultrasonic wave generated by the converter 71 and transmits it to the horn 73. The horn 73 transfers the ultrasonic vibration amplified by the booster 72 to the cutter 74. Preferably, the cutter 74 may be the vertical cutter 60 described above. In this case, the lower portion of the cutter body 61 of the vertical cutter 60 may be coupled to the horn 73 by bolt/nut fastening, riveting, or welding. When the horn 73 to which the cutter 74 is coupled is moved in the axial direction (Y) while being in contact with the winding turns 48 and 49, the winding turns 48 and 49 are moved in the axial direction by the ultrasonically vibrating cutter 74 ( cut into Y).

Although not shown, the ultrasonic cutting device 70 is a mechanical and/or electronic mechanism for linear movement and/or rotational movement of the horn 73, including a station to which a work piece is fixed; and/or a servo motor and/or a linear motor and/or an air cylinder supporting the linear movement and/or rotational movement of the horn 73; and/or their driving sources; and/or electronic control devices thereof.

Configurations of the converter 71, the booster 72, and the horn 73 of the ultrasonic cutting device 70 are well known in the art. In addition, it is apparent to those skilled in the art that various parts required for linear movement and/or rotational movement of the horn 73 may be additionally coupled to the ultrasonic cutting device 70. .

Those skilled in the art to which the present invention pertains will understand that the structure of the vertical cutter 60 can be modified in various forms.

10 to 12 are plan views of vertical cutters 60a, 60b, and 60c according to various modifications of the present invention.

Referring to FIGS. 10 to 12 , the vertical cutter 60a may have a structure in which a pair of cutter knives 62 radially extend at an angle of 120 degrees to each other. In addition, the vertical cutter 60b may have a structure in which a pair of cutter knives 62 radially extend at an angle of 180 degrees to each other.

In another modification, the vertical cutter 60c may include a cutter knife 62 having an arc shape recessed toward the center of the cutter body 61 . The circular arc shape corresponds to the circular arc of a circle having an eccentricity of 1. The circular arc shape of the cutter knife 62 may be point symmetrical, left-right symmetrical, or up-and-down symmetrical with respect to the center of the cutter body 61 . The cutter knives 62 have a radially extending structure based on the center of the cutter body 61 even though they have an arc shape. The number of cutter knives 62 having an arc shape is not limited to four, and can be adjusted to two or three. In this case, it is preferable that the cutter knives 62 are arranged at equal intervals in the circumferential direction of the cutter body 61 .

The cross-sectional structure of the cutter knives 62 included in the vertical cutters 60a, 60b, and 60c of various embodiments is substantially the same as that shown in FIG. 8 and will be used as the cutter 74 of the ultrasonic cutting device 70. can In this case, the cutter body 61 may be coupled to the horn 73 of the ultrasonic cutting device 70.

On the other hand, according to an embodiment of the present invention, the winding turns 48 and 49 respectively provided on the upper and lower portions of the electrode assembly 50 rotate in the axial direction Y by the vertical cutters 60, 60a, 60b, and 60c. After being cut along, the area around the bending target area may be cut perpendicularly to the axial direction Y so that the bending target area (bend portion) remains (remains) in a protruding shape along the axial direction Y.

Preferably, the area around the bending target area can be cut by the horizontal cutter 80 .

13 is a plan view illustrating an example of a horizontal cutter 80 according to an embodiment of the present invention, and FIG. 14 is a cross-sectional view taken along line BB′ of FIG. 13 .

13 and 14, the horizontal cutter 80 may include a cutter knife 81 and a cutter body 82. The horizontal cutter 80 may ultrasonically cut the peripheral area of the plurality of bending target areas spaced apart in the circumferential direction perpendicular to the axial direction (Y). When the peripheral area is ultrasonically cut by the horizontal cutter 80, a plurality of uncoated flags 48c protrude along the axial direction Y from the first cutting surface 51 as shown in FIG. 6B.

The cutter knife 81 may have a polygonal shape. Preferably, the polygonal shape may correspond to the shape of the area to be cut. That is, the cutter knife 81 is coupled to the cutter body 82 so as to be placed on a cutting plane perpendicular to the axial direction Y of the electrode assembly 50, and the bending target regions (bend parts) adjacent in the circumferential direction. It may have a shape corresponding to the winding turn area between.

In one example, when the shape of an area to be cut is a right triangle, the cutter knife 81 has a right triangle shape. In another example, when the shape of the region to be cut is an isosceles triangle with an obtuse angle greater than 90 degrees (for example, 120 degrees) at the vertex facing the hypotenuse, the cutter knife 81 also has an isosceles obtuse triangle shape. In another example, when the shape of the area to be cut is an acute (for example, 60 degree) isosceles triangle in which the interior angle of the vertex facing the hypotenuse is less than 90 degrees, the cutter knife 81 also has an acute isosceles triangle shape. Like the cutter knife 62 of the vertical cutter 60, the lower part of the cutter knife 81 may be embedded in the cutter body 82 or welded to the cutter body 82.

The cutter knife 81 of the horizontal cutter 80 may form a first cutting surface 51 perpendicularly meeting the second cutting surface 52 having a flat surface as shown in FIG. 6B.

15 is a plan view showing an example of a horizontal cutter 90 according to another embodiment of the present invention, and FIG. 16 is a cross-sectional view taken along line C-C′ of FIG. 15 .

15 and 16, the horizontal cutter 90 includes a rotary knife 91 having a disk shape and a cutter body 92. The rotating knife 91 is installed on the rotating mechanism 93 so as to be rotatable in one direction. The rotating shaft of the rotating knife 91 may be fastened to the bearing 94 of the rotating mechanism 93 . The rotation mechanism 93 may be coupled with a motor (not shown) to rotate the cutter knife 91 .

The radius of the rotary knife 91 may be substantially the same as the radius of the imaginary circle R shown in FIG. 6D. Referring to FIG. 6D , the rotary knife 91 may form a first cutting surface 51 perpendicularly meeting the second cutting surface 52 having a round shape.

The horizontal cutters 80 and 90 may be coupled to the horn 73 as the cutter 74 of the ultrasonic cutting device 70. The manner in which the horizontal cutters 80 and 90 are coupled to the horn 73 is substantially the same as the manner in which the vertical cutter 60 is coupled to the horn 73.

The horizontal cutters 80 and 90 approach the winding turns 48 and 49 formed by the uncoated parts on a plane perpendicular to the axial direction Y of the electrode assembly 50, and according to the shape of the cutter knife, the winding turns 48 , 49) can be cut. The rotary knife 91 of the horizontal cutter 90 can be rotated at high speed to cut the winding turns 48 and 49 . Preferably, when the horizontal cutters 80 and 90 are used as the cutter 74 of the ultrasonic cutting device 70, the winding turns 48 and 49 can be cut by the cutter knives 81 and 91 that vibrate ultrasonically. there is.

Hereinafter, a process of cutting the winding turns 48 and 49 by the vertical cutter (60 in FIG. 7) and the horizontal cutter (80 in FIG. 13) will be described in detail.

17 is a view showing a state after forming the cutting line 100 on the winding turns 48 and 49 of the electrode assembly 50 using the vertical cutter 60 according to an embodiment of the present invention.

Referring to FIG. 17, first, the cutter knife 61 is opposed to the upper surface of the electrode assembly 50 while the vertical cutter 60 is vibrated with ultrasonic waves, and the vertical cutter 60 is moved along the axial direction (Y) to wind the coil. The cutting line 100 is formed at the edge of the bending target region D by cutting the upper portions of the turns 48 and 49 to a predetermined depth.

The bending target region D corresponds to a region where the uncoated flags are bent along the radial direction of the electrode assembly 50 for welding with the current collecting plate. The cutting line 100 corresponds to an area where the upper portions of the winding turns 48 and 49 are cut in a line slit shape.

Preferably, the cutting depth may be 2 mm to 10 mm. The lowermost point at which the vertical cutting using the vertical cutter 60 ends is higher than the end of the insulating coating layer 47 exposed to the outside of the separator 45 (point indicated by the arrow) as shown in FIG. 6A in consideration of the cutting tolerance. can be

18 is a process of cutting the winding turns 48 and 49 in a plane (XZ plane) perpendicular to the axial direction (Y) of the electrode assembly 50 using the horizontal cutter 80 according to an embodiment of the present invention. is a drawing showing

Referring to FIG. 18, after forming the cutting line 100 at the edge of the bending target region D, the horizontal cutter 80 is ultrasonically vibrated while the plane perpendicular to the axial direction Y of the electrode assembly 50 On (XZ), the cutter knife 81 is moved toward the core of the electrode assembly 50 to cut the winding portion between adjacent bending target regions D in the circumferential direction.

Preferably, the position at which the horizontal cutting is performed may be the lowest point at which the vertical cutting ends (a point indicated by an arrow in FIG. 6A) or an upper point thereof. As the horizontal cutter 80 moves toward the center of the core C of the electrode assembly 50, an area overlapping with the cutter knife 81 (hatching area) is cut, and the cutter knife 81 cuts the bending target area D When moving to the edge of ), all of the winding turns 48 and 49 around the bending target region D are cut and removed. As a result, the bending target region D remains (remains) in a state of protruding upward from the first cutting surface 51 along the axial direction (Y) direction of the electrode assembly 50 .

Preferably, the bending target region D extends radially along the radial direction when viewed in the axial direction Y of the electrode assembly 50 and may be disposed at the same angle along the circumferential direction.

Preferably, the bending target region D may have a cross shape extending outward from the center of the core of the electrode assembly 50 when viewed in the axial direction Y of the electrode assembly 50 .

Next, the process of cutting the winding turns 48 and 49 respectively provided on the upper and lower parts of the electrode assembly 50 by the vertical cutter (60c in FIG. 12) and the horizontal cutter (90 in FIG. 15) will be described in detail. do.

19 is a view showing a state after forming the cutting line 100 on the winding turns 48 and 49 of the electrode assembly 50 using the vertical cutter 60c according to an embodiment of the present invention.

Referring to FIG. 19, first, the cutter knife 61 faces the upper surface of the electrode assembly 50 while ultrasonically vibrating the vertical cutter 60c, and the vertical cutter 60c is moved along the axial direction Y to wind the winding. A cutting line 100 is formed at the edge of the bending target region D by cutting the turns 48 and 49 to a predetermined depth. The cutting line 100 has an arc shape curved toward the center of the core of the electrode assembly 50 . The arc corresponds to the arc of a circle with an eccentricity of 1. The bending target area D has a cross shape and has an arc shape at the edge.

The bending target region D corresponds to a region where the uncoated flags are bent along the radial direction of the electrode assembly 50 for welding with the current collecting plate. The cutting line 100 corresponds to a region in which the winding turns 48 and 49 are removed along the axial direction Y of the electrode assembly 50 . Preferably, the cutting depth may be 2 mm to 10 mm.

As shown in FIG. 6A, the lowest point at which the vertical cutting using the vertical cutter 60c ends is higher than the end of the insulating coating layer 47 exposed to the outside of the separator 45 in consideration of the cutting tolerance (point indicated by the arrow). ) is preferred.

20 is a surface area bent in a plane (XZ plane) perpendicular to the axial direction (Y) of the electrode assembly 50 using a horizontal cutter 90 including a rotary knife 91 according to an embodiment of the present invention. (D) It is a view showing the process of cutting the winding portion around the turn.

Referring to FIG. 20, after forming the arc-shaped cutting line 100 at the edge of the bending target area D, while ultrasonically vibrating the rotary knife 91 of the horizontal cutter 90, the axis of the electrode assembly 50 On a plane (XZ) perpendicular to the direction (Y), the rotary knife (91) is moved toward the core of the electrode assembly (50) to cut the turn-around area existing outside the arc-shaped cutting line (100). In some cases, it is also possible to cut the winding turn portion only by rotation of the rotary knife 91 without applying ultrasonic vibration to the rotary knife 91 of the horizontal cutter 90 .

Preferably, the position at which the horizontal cutting is performed may be the lowest point at which the vertical cutting ends (a point indicated by an arrow in FIG. 6A) or an upper point thereof. As the horizontal cutter 90 moves toward the center of the core of the electrode assembly 50, an area overlapping with the rotating knife 91 (hatching area) is cut, and the rotary knife 91 cuts the edge of the bending target area D. When moving to , all of the winding turns of the remaining parts except for the bending target region (D) are cut and removed. As a result, the bending target region D remains (remains) in a state of protruding upward from the first cutting surface 51 along the axial direction (Y) direction of the electrode assembly 50 .

Preferably, the radius of curvature of the rotary knife 91 of the horizontal cutter 90 may be substantially equal to or smaller than the radius of curvature of the cutting line 100 . In the latter case, the turn-up area outside the cutting line 100 may be cut by combining the linear movement and rotational movement of the rotary knife 91 .

21 to 24 are top plan views showing the arrangement structure of the bending target area D after the winding turns 48 and 49 are cut according to an embodiment of the present invention.

In the drawings, the bending target region D protrudes from the first cutting surface 51 perpendicular to the axial direction Y to the top of the electrode assembly 50 .

In each figure, the structure of the cutter is shown on the cross-sectional structure of the electrode assembly 50. The bending target region D shown in FIGS. 21 to 23 may be formed by sequentially using the vertical cutter 60 and the horizontal cutter 80 . Also, the bending target region D shown in FIG. 24 may be formed by sequentially using a vertical cutter 60c and a horizontal cutter 90 including a rotary knife 91 .

Preferably, as shown in FIG. 5, the uncoated portion near the core of the electrode assembly 50 is lower than the uncoated portion of the other portions. Therefore, the bending target region D may not be formed near the core.

According to another aspect of the present invention, the bending target region D formed by cutting the winding turns 48 and 49 of the electrode assembly 50 includes a plurality of uncoated flags 48c along the radial direction. The plurality of uncoated flags 48c may be bent in a radial direction of the electrode assembly 50, preferably from the outer circumferential side to the core side.

Preferably, the height of the uncoated flag 48c in the axial direction (Y) is adjusted in the range of 2 mm to 10 mm so that when the uncoated flag 48c is bent along the radial direction, the electrode assembly 50 as shown in FIG. 6C At least 3 or more, or at least 4 or more, at least 5 or more, at least 6 or more, at least 7 or more, at least 8 or more, at least 9 or more, or at least 10 or more in the axial direction (Y) of can

The bending target region D has a shape protruding from the first cutting surface 51 along the axial direction Y of the electrode assembly 50 and has a structure extending radially along the bending direction. Also, the uncoated flags 48c included in the bending target region D have a narrow width in the circumferential direction. Accordingly, when the uncoated flags 48c included in the bending target region D are bent along the radial direction of the electrode assembly 50, the bending is performed uniformly. In addition, as the uncoated flags 48c are stacked in several layers along the axial direction Y, the flatness of the bending surface region (F in FIG. 6C) is improved. In addition, welding the current collecting plate to the bent surface area F having improved flatness can increase the welding power to sufficiently increase the welding strength and improve the resistance characteristics of the welding interface.

The electrode assembly 50 according to an embodiment of the present invention may be applied to a jelly roll type cylindrical battery.

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

Here, the form factor means a value representing the diameter and height of a cylindrical battery. A cylindrical battery according to an embodiment of the present invention may be, for example, a 46110 battery, a 4875 battery, a 48110 battery, a 4880 battery, or a 4680 battery. In the figures representing the form factor, the first two numbers represent the diameter of the battery, and the remaining numbers represent the height of the battery.

When an electrode assembly having a tab-less structure is applied to a cylindrical battery having a form factor ratio of greater than 0.4, stress applied in a radial direction when bending the uncoated portion is large, and thus the uncoated portion is easily torn. In addition, when the current collector plate is welded to the bent surface area of the uncoated portion, the number of overlapping layers of the uncoated portion must be sufficiently increased in order to sufficiently secure welding strength and lower resistance. These requirements can be achieved by electrodes and electrode assemblies according to embodiments (modifications) of the present invention.

A battery according to an embodiment of the present invention may be a cylindrical battery having a diameter of about 46 mm, a height of about 110 mm, and a form factor ratio of 0.418.

A battery according to another embodiment may be a cylindrical battery having a diameter of about 48 mm, a height of about 75 mm, and a form factor ratio of 0.640.

A battery according to another embodiment may be a cylindrical battery having a diameter of about 48 mm, a height of about 110 mm, and a form factor ratio of 0.436.

A battery according to another embodiment may be a cylindrical battery having a diameter of about 48 mm, a height of about 80 mm, and a form factor ratio of 0.600.

A battery according to another embodiment may be a cylindrical battery having a diameter of about 46 mm, a height of about 80 mm, and a form factor ratio of 0.575.

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

Hereinafter, a cylindrical battery according to an embodiment of the present invention will be described in detail.

25A is a cross-sectional view of a cylindrical battery 190 cut along an axial direction Y according to an embodiment of the present invention.

Referring to FIG. 25A, a cylindrical battery 190 according to an embodiment of the present invention includes an electrode assembly 110 including a positive electrode, a separator, and a negative electrode wound in a jelly roll shape, and a battery housing accommodating the electrode assembly 110. 142 and a seal 143 sealing the open end of the battery housing 142. The electrode assembly 110 has the structure of the above-described embodiment.

The battery housing 142 is a cylindrical container with an opening formed thereon. The battery housing 142 is made of a conductive metal material such as aluminum, steel, or stainless steel. The battery housing 142 accommodates the electrode assembly 10 in the inner space through the top opening and also accommodates the electrolyte. A Ni coating layer may be formed on the outer and/or inner surface of the battery housing 142 .

The electrolyte may be a salt having a structure such as A ⁺ B ^-- . Here, A ⁺ includes alkali metal cations such as Li ⁺ , Na ⁺ , and K ⁺ or ions made of combinations thereof. And B ^- is F ^- , Cl ^- , Br ^- , I ^- , NO ₃ ^- , N(CN) ₂ ^- , BF ₄ ^- , ClO ₄ ^- , AlO ₄ ^- , AlCl ₄ ^- , PF ₆ ^- , SbF ₆ ^- , AsF ₆ ^- , BF ₂ C ₂ O ₄ ^- , BC ₄ O ₈ ^- , (CF ₃ ) ₂ PF ₄ ^- , (CF ₃ ) ₃ PF ₃ ^- , (CF ₃ ) ₄ PF ₂ ^- , (CF ₃ ) ₅ PF ^- , (CF ₃ ) ₆ P ^- , CF ₃ SO ₃ ^- , C ₄ F ₉ SO ₃ ^- , CF ₃ CF ₂ SO ₃ ^- , (CF ₃ SO ₂ ) ₂ N ^- , (FSO ₂ ) ₂ N ^- _, CF ₃ CF ₂ (CF ₃ ) ₂ CO ^- , (CF ₃ SO ₂ ) ₂ CH ^- , (SF ₅ ) ₃ C ^- , (CF ₃ SO ₂ ) ₃ C ^- , CF ₃ (CF ₂ ) ₇ SO ₃ ^- , CF ₃ CO ₂ ^- , CH ₃ CO ₂ ^- , SCN ^- and (CF ₃ CF ₂ SO ₂ ) ₂ N ^- includes any one or more anions selected from the group consisting of.

The electrolyte can also be used by dissolving it in an organic solvent. As the organic solvent, 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 2-pyrrolidone (NMP), ethyl methyl carbonate (EMC), γ-butyrolactone, or mixtures thereof may be used.

The electrode assembly 110 may have a jelly roll shape. As shown in FIG. 2, the electrode assembly 110 is formed by sequentially stacking a lower separator, an anode, an upper separator, and a negative electrode at least once. can be manufactured.

An anode uncoated portion 146a and a cathode uncoated portion 146b protrude from the upper and lower portions of the electrode assembly 110, respectively. The uncoated portion 146a of the positive electrode forms the turn portion 48 at the upper portion of the electrode assembly 110, and the uncoated portion 146b of the negative electrode forms the turn portion 49 at the lower portion of the electrode assembly 110. The winding turns 48 and 49 include bent parts and cut parts that are alternately disposed along the circumferential direction. Examples of the bending portion and the cutting portion have been described above with reference to FIGS. 6B and 6D.

The sealing body 143 provides airtightness between the cap 143a, the cap 143a and the battery housing 142 and electrically and mechanically connects the sealing gasket 143b having insulation and the cap 143a. A plate 143c may be included.

The cap 143a is a component made of a conductive metal material and covers an upper opening of the battery housing 142 . The cap 143a is electrically connected to the bent portion 48b of the positive electrode winding portion 48 and electrically insulated from the battery housing 142 through a sealing gasket 143b. Accordingly, the cap 143a can function as a positive electrode terminal of the cylindrical battery 140 .

The cap 143a is seated on the beading portion 147 formed in the battery housing 142 and fixed by the crimping portion 148 . A sealing gasket 143b may be interposed between the cap 143a and the crimping portion 148 to ensure airtightness of the battery housing 142 and to electrically insulate the battery housing 142 and the cap 143a. The cap 143a may include a protruding portion 143d protruding upward from the center thereof.

The battery housing 142 is electrically connected to the bent portion of the negative electrode winding portion 49 . Therefore, the battery housing 142 has the same polarity as the negative electrode.

The battery housing 142 has a beading part 147 and a crimping part 148 at the top. The beading portion 147 is formed by press fitting around the outer circumferential surface of the battery housing 142 . The beading part 147 prevents the electrode assembly 110 accommodated inside the battery housing 142 from escaping through the top opening of the battery housing 142, and may function as a support on which the sealing body 143 is seated. .

The crimping portion 148 is formed above the beading portion 147 . The crimping portion 148 has an extended and bent shape to surround the outer circumferential surface of the cap 143a disposed on the beading portion 147 and a portion of the upper surface of the cap 143a.

The cylindrical battery 190 may further include a first collector plate 144 and/or a second collector plate 145 and/or an insulator 146 .

25B and 25C are top plan views showing structures of the first current collector plate 144 and the second collector plate 145, respectively.

Referring to FIGS. 25B and 25C , the first current collecting plate 144 is coupled to the upper portion of the electrode assembly 110 . The first current collecting plate 144 is made of a conductive metal material such as aluminum, copper, or nickel.

The first collector plate 144 is welded to the welding target region of the bent surface region (F in FIG. 6C) formed by bending the uncoated flags included in the bent portion of the winding turn portion 48 of the anode.

Preferably, in the welding target region, the average number of uncoated flags stacked in the axial direction (Y) of the electrode assembly 110 may be 5 or more. Also, in the welding target region, the average stacking thickness of the uncoated flags may be 50 um or more.

The first current collector plate 144 includes a support portion 144a, a plurality of leg portions 144b extending outwardly from the support portion 144a, and extending outwardly from the support portion 144a between adjacent leg portions 144b. A lead part 149 may be included. The lead part 149 may extend from any one of the leg parts 144b, unlike shown.

The support portion 144a is seated near the core of the electrode assembly 110, and the plurality of leg portions 144b may be welded to the welding target region of the bent surface region while seated on the bent surface region.

A hole H ₁ is provided at the center of the support portion 144a. The electrolyte may be injected through the hole H ₁ . The diameter of the hole H ₁ is more than 0.5 times the diameter of the cavity in the core of the electrode assembly 110 . If the diameter of the hole H ₁ is smaller than the diameter of the cavity in the core, when a vent occurs in the cylindrical battery 190, it is possible to prevent the electrode or separator from escaping through the cavity of the core. In addition, when the diameter of the hole H ₁ is equal to or greater than the diameter of the cavity in the core, a welding jig can be easily inserted in the process of welding the second current collector plate 145 to the bottom of the battery housing 142, and the electrolyte solution Injection can be made smoothly.

The lead part 149 may extend upward from the electrode assembly 110 and be coupled to the connection plate 143c or directly coupled to the lower surface of the cap 143a. The connection plate 143c may be coupled to the lower surface of the cap 143a. The lead part 149 and other components may be coupled through welding.

The coupling between the bent surface area formed by bending the uncoated flags and the first current collector plate 144 may be performed by laser welding. Laser welding can be replaced with resistance welding or ultrasonic welding.

Referring to FIGS. 25A and 25C , a plate-shaped second current collecting plate 145 may be coupled to the lower surface of the electrode assembly 110 .

The second current collector plate 145 is provided inside a support portion 145a having a hole H ₂ , a plurality of leg portions 145b extending outwardly from the support portion 145a, and a hole H ₂ to form a battery housing 142 ) may include a connection part 145c coupled to the bottom surface of the bridge part 145d connecting the connection part 145c and the support part 145a.

The second current collecting plate 145 is made of a conductive metal material such as aluminum, copper, or nickel. The support portion 145a is seated near the core on the lower surface of the electrode assembly 110 . The plurality of leg portions 145b are welded to the welding target region of the bent surface region formed by bending the uncoated flags of the cathode winding portion 49 . The connection portion 145c may be welded on the inner bottom surface of the battery housing 142 .

The diameter of the connecting portion 145c is larger than the diameter of the cavity in the core of the electrode assembly 110 . The bridge part 145d connects the inner surface of the hole H ₂ and the outer surface of the connection part 145c. The bridge portion 145d functions to absorb vibration or stress when vibration or stress is applied to the second current collecting plate 145 . The width or thickness of the bridge portion 145d may be partially reduced. Then, when an overcurrent flows through the bridge portion 145d, the bridge portion 145d is melted and disconnected, so that the overcurrent can be blocked.

Preferably, in the welding target region, the average number of uncoated flags stacked in the axial direction (Y) of the electrode assembly 110 may be 5 or more. Also, in the welding target region, the average stacking thickness of the uncoated flags may be 50 um or more.

Referring to FIGS. 25B and 25C , a welding pattern W ₁ formed on the leg portion 144b of the first current collecting plate 144 and a welding pattern formed on the leg portion 145b of the second current collecting plate 145 (W ₂ ) may start from a point spaced apart from the center of the core of the electrode assembly 110 by a substantially equal distance and extend in a radial direction. The radial length of the welding pattern (W ₁ ) may be the same as or different from the radial length of the welding pattern (W ₂ ). The welding patterns W ₁ and W ₂ may be continuous or discontinuous arrays of welding beads.

Referring to FIG. 25A , the insulator 146 may cover the first current collecting plate 144 . The insulator 146 may prevent direct contact between the first current collecting plate 144 and the inner circumferential surface of the battery housing 142 by covering the first current collecting plate 144 on the upper surface of the first current collecting plate 144 . .

The insulator 146 has a lead hole 151 through which the lead portion 149 extending upward from the first current collecting plate 144 can be drawn out. The lead portion 149 is drawn upward through the lead hole 151 and coupled to the lower surface of the connecting plate 143c or the lower surface of the cap 143a.

An area around the edge of the insulator 146 may be interposed between the first current collecting plate 144 and the beading portion 147 to fix the combination of the electrode assembly 110 and the first current collecting plate 144 . Accordingly, the assembly of the electrode assembly 110 and the first current collecting plate 144 is limited in movement in the axial direction (Y), so that assembly stability of the cylindrical battery 190 can be improved.

The insulator 146 may be made of an insulating polymer resin. In one example, insulator 146 may be made of polyethylene, polypropylene, polyimide or polybutyleneterephthalate.

The battery housing 142 may further include a venting portion 152 formed on a lower surface thereof. The venting portion 152 corresponds to an area of the lower surface of the battery housing 142 having a smaller thickness than the surrounding area. The vent 152 is structurally weak compared to the surrounding area. Therefore, when an abnormality occurs in the cylindrical battery 190 and the internal pressure increases to a predetermined level or more, the venting part 152 is ruptured and the gas generated inside the battery housing 142 may be discharged to the outside.

The venting portion 152 may be continuously or discontinuously formed on the lower surface of the battery housing 142 in a circular motion. In a variation, the vents 152 may be formed in a rectilinear pattern or some other pattern.

Since the diameter of the connection portion 145c of the second current collecting plate 145 is larger than the diameter of the cavity in the core of the electrode assembly 110, the venting portion 152 is ruptured and the gas generated inside the battery housing 142 is released. When discharged to the outside, it is possible to prevent electrodes or separators near the core from escaping.

26A is a cross-sectional view of a cylindrical battery 200 according to another embodiment of the present invention taken along the axial direction (Y).

Referring to FIG. 26A, the cylindrical battery 200 is different from the cylindrical battery 190 shown in FIG. 25A in that the structure of the electrode assembly is substantially the same and the structure except for the electrode assembly is changed.

Specifically, the cylindrical battery 200 includes a battery housing 171 through which a terminal 172 is installed. The terminal 172 may be a rivet terminal in which an edge of one end is riveted to the inner surface of the closed portion of the battery housing 171 . The terminal 172 is installed in the closed portion (upper part of the drawing) of the battery housing 171 . The terminal 172 is riveted to the through hole of the battery housing 171 with the insulating gasket 173 interposed therebetween. The terminal 172 is exposed to the outside in a direction opposite to the direction of gravity.

The terminal 172 includes a terminal exposed portion 172a and a terminal inserted portion 172b. The terminal exposed portion 172a is exposed to the outside of the closed portion of the battery housing 171 . The terminal exposed portion 172a may be located at approximately the center of the closed portion of the battery housing 171 . The maximum diameter of the terminal exposed portion 172a may be larger than the maximum diameter of the through hole formed in the battery housing 171 . The terminal insertion portion 172b may be electrically connected to the bent portion of the positive electrode winding portion 48 through a substantially central portion of the closed portion of the battery housing 171 . The portion where the electrical connection is made is a bending surface area formed by bending the uncoated flags of the anode winding portion 48 . The terminal insertion portion 172b may be rivet-coupled to the inner surface of the closed portion of the battery housing 171 . That is, the end edge of the terminal insertion portion 172b may be bent toward the inner surface of the battery housing 171 by being pressed by a caulking jig. The maximum diameter of the end of the terminal insertion portion 172b may be greater than the maximum diameter of the through hole of the battery housing 171 .

The lower surface of the terminal insertion portion 172b is substantially flat and may be welded to the first collector plate 144' connected to the bent portion of the positive electrode winding portion 48.

26B is a top plan view showing the structure of the first current collecting plate 144'. Referring to FIG. 26B, the first current collecting plate 144' has substantially the same structure as the current collecting plate 145 shown in FIG. 25C. That is, the first current collecting plate 144' includes a support portion 144a' including a hole H ₃ , a plurality of leg portions 144b' extending in a radial direction from the support portion 144', and a hole H ₃ ) It may include a connection part 144c' provided inside and a bridge part 144d' connecting the support part 144a' and the connection part 144c'. The connection portion 144c' of the first current collecting plate 144' may be welded to a flat lower end of the terminal insertion portion 172b of the terminal 172. The plurality of leg portions 144b' may be welded to a welding target area defined by a bending surface area of the anode winding turn portion 48.

Referring to FIG. 26A , an insulator 174 made of an insulating material may be interposed between the first current collecting plate 144 ′ and the inner surface of the battery housing 171 . The insulator 174 covers an upper portion of the first current collecting plate 144' and an upper edge portion of the electrode assembly 110. Accordingly, it is possible to prevent a short circuit from being caused by contacting the inner surface of the battery housing 171 having a different polarity with the first current collecting plate 144'. Preferably, the terminal insertion portion 172b of the terminal 172 may pass through the insulator 174 and be welded to the first collector plate 144'. The insulator 174 is made of an insulating polymer resin.

The insulating gasket 173 is interposed between the battery housing 171 and the terminal 172 to prevent electrical contact between the battery housing 171 and the terminal 172 having opposite polarities. As a result, the upper surface of the battery housing 171 having a substantially flat shape can function as a negative electrode terminal of the cylindrical battery 200 .

The insulating gasket 173 includes a gasket exposed portion 173a and a gasket inserted portion 173b. The gasket exposed portion 173a is interposed between the terminal exposed portion 172a of the terminal 172 and the battery housing 171 . The gasket insertion portion 173b is interposed between the terminal insertion portion 172b of the terminal 172 and the battery housing 171 . The gasket insertion portion 173b may be deformed together during riveting of the terminal insertion portion 172b and adhered to the inner surface of the battery housing 171 . The insulating gasket 173 may be made of, for example, a polymer resin having insulating properties.

The gasket exposed portion 173a of the insulating gasket 173 may have an extended shape to cover the outer circumferential surface of the terminal exposed portion 172a of the terminal 172 . When the insulating gasket 173 covers the outer circumferential surface of the terminal 172, it is possible to prevent a short circuit from occurring during the process of coupling an electrical connection part such as a bus bar to the upper surface of the battery housing 171 and/or to the terminal 172. can Although not shown in the drawing, the gasket exposed portion 173a may have an extended shape to cover not only the outer circumferential surface of the terminal exposed portion 172a but also a portion of the upper surface thereof.

In the case where the insulating gasket 173 is made of a polymer resin, the insulating gasket 173 may be coupled to the battery housing 171 and the terminal 172 by thermal fusion. In this case, airtightness at the bonding interface between the insulating gasket 173 and the terminal 172 and at the bonding interface between the insulating gasket 173 and the battery housing 171 may be enhanced. Meanwhile, in the case where the gasket exposed portion 173a of the insulating gasket 173 extends to the upper surface of the terminal exposed portion 172a, the terminal 172 is integrally formed with the insulating gasket 173 by insert injection molding. can be combined

Of the upper surface of the battery housing 171, the area 175 other than the area occupied by the terminal 172 and the insulating gasket 173 corresponds to an electrode terminal having a polarity opposite to that of the terminal 172.

26C is a perspective view showing the structure of the second current collecting plate 176. Referring to FIGS. 26A and 26C , the second current collecting plate 176 is coupled to the lower portion of the electrode assembly 110 . The second current collecting plate 176 is made of a conductive metal material such as aluminum, steel, copper, or nickel. The second current collecting plate 176 may be coupled to a welding target region of a bent surface region formed on the negative electrode winding portion 49 through welding.

The second current collector plate 176 includes a support portion 176a and a plurality of leg portions 176b extending in a radial direction from the support portion 176a and welded to a welding target region. The support part 176a includes a hole H ₄ in the center. Electrolyte may be injected through the hole H ₄ . The diameter of the hole H ₄ is 0.5 times greater than the diameter of the cavity in the core of the electrode assembly 110 . The function of the hole H ₄ is substantially the same as that of the hole H ₁ described above.

Preferably, at least a portion of the second current collecting plate 176 may be electrically connected to the battery housing 171 . In one example, at least a portion of an edge portion of the second current collecting plate 176 may be interposed and fixed between the inner surface of the battery housing 171 and the sealing gasket 178b. To this end, the second current collector plate 176 includes a housing connector 176c. The housing connection part 176c includes a connection part 176c2 extending obliquely from the end of the leg part 176b toward the lower surface of the beading part 180 and a contact part 176c1 disposed on the lower surface of the beading part 180. do. Unlike the illustration, the connecting portion 176c2 may extend from the region of the support portion 176a between the leg portions 176b. The contact portion 176c1 may extend in an arc shape along the circumferential direction of the beading portion 180 to increase a contact area with the beading portion 180 .

At least a portion of the edge of the second current collecting plate 176, for example, the contact portion 176c1, is supported on the bottom surface of the beading portion 180 formed at the bottom of the battery housing 171 and welded to the beading portion 180. ) can be fixed. In a modified example, at least a portion of an edge portion of the second current collector plate 176 may be directly welded to the inner wall surface of the battery housing 171 .

Preferably, the second current collecting plate 176 and the welding target area included in the bent surface area of the negative electrode winding portion 49 may be coupled by laser welding. At this time, the welding is performed in an area where the average number of stacked flags in the uncoated area is 5 or more in the axial direction (Y) in the bending surface area or in an area where the average stacked thickness of the flags in the uncoated area is 25 μm or more. Laser welding can be replaced by resistance welding, ultrasonic welding, spot welding, and the like.

Meanwhile, the welding pattern W 1 formed on the leg portion 144b' of the first current collecting plate ₁₄₄ ' and the welding pattern W ₂ formed on the leg portion 176b of the second current collecting plate 176 are It may start from a point spaced apart from the center of the core of the electrode assembly 110 by a substantially equal distance and extend in a radial direction. The radial length of the welding pattern (W ₁ ) may be the same as or different from the radial length of the welding pattern (W ₂ ). In one example, the radial length of the welding pattern W ₁ is longer than the radial length of the welding pattern W ₂ . This is because the leg portion 176b of the second current collecting plate 176 is shorter than the leg portion 144b' of the first current collecting plate 144' since the second current collecting plate 176 includes the connecting portion 176c2. At least one welding pattern W ₃ is also formed on the contact portion 176c1 of the second current collecting plate 176 . The welding pattern (W ₃ ) may have a shape of a straight line or an arc. The welding patterns (W ₁ , W ₂ , W ₃ ) may be continuous welding beads or discontinuous arrays of welding beads.

The sealing body 178 sealing the lower open end of the battery housing 171 includes a cap 178a and a sealing gasket 178b. The sealing gasket 178b electrically separates the cap 178a and the battery housing 171. The crimping portion 181 fixes the edge of the cap 178a and the sealing gasket 178b together. The cap 178a is provided with a vent 179. The configuration of the vent portion 179 is substantially the same as that of the above-described embodiment.

Preferably, the cap 178a is made of a conductive metal material. However, since the sealing gasket 178b is interposed between the cap 178a and the battery housing 171, the cap 178a has no electrical polarity. The sealing body 178 serves to seal the open end of the lower portion of the battery housing 171 and to discharge gas when the internal pressure of the battery 200 increases above a critical value. The cap 178a may include a vent portion 179 at an edge area of the flat portion. The configuration of the vent portion 179 is substantially the same as that of the foregoing embodiment.

Preferably, the terminal 172 electrically connected to the bent portion of the positive electrode winding portion 48 through the first current collector plate 144' is used as the first electrode terminal. In addition, the portion 175, excluding the terminal 172, of the upper surface of the battery housing 171 electrically connected to the bent portion of the negative electrode winding portion 49 through the second current collecting plate 176 has a polarity with the first electrode terminal. This other second electrode terminal is used. As such, when the two electrode terminals are located on the top of the cylindrical battery 200, it is possible to dispose an electrical connection component such as a bus bar on only one side of the cylindrical battery 200. This can lead to simplification of the battery pack structure and improvement of energy density. In addition, since the portion 175 used as the second electrode terminal has a substantially flat shape, a sufficient bonding area can be secured for bonding electrical connection components such as bus bars. Accordingly, in the cylindrical battery 200, resistance at the junction of the electrical connecting parts can be reduced to a desirable level.

In the present invention, as shown in FIG. 5, the uncoated portion constituting the winding turn near the core has a low height. Therefore, even if the uncoated flags of the bending target region D are bent toward the center of the core C of the electrode assembly 110, the cavity 112 of the core C may be opened upward without being blocked.

If the cavity 112 is not blocked, there is no difficulty in the electrolyte injection process, and the electrolyte injection efficiency is improved. In addition, a welding process between the current collector plate 145 and the bottom of the battery housing 142 or between the current collector plate 144′ and the terminal 172 can be easily performed by inserting a welding jig through the cavity 112. .

A cylindrical battery according to the above-described embodiments (modifications) can be used to manufacture a battery pack.

27 is a diagram schematically illustrating the configuration of a battery pack according to an embodiment of the present invention.

Referring to FIG. 27 , a battery pack 300 according to an embodiment of the present invention includes an assembly to which cylindrical batteries 301 are electrically connected and a pack housing 302 accommodating them. The cylindrical battery 301 may be any one of the batteries according to the above-described embodiments (modifications). In the drawings, for convenience of illustration, parts such as a bus bar, a cooling unit, and external terminals for electrically connecting the cylindrical batteries 301 are omitted.

The battery pack 300 may be mounted in a vehicle. The vehicle may be, for example, an electric vehicle, a hybrid vehicle, or a plug-in hybrid vehicle. Vehicles include four-wheeled vehicles or two-wheeled vehicles.

FIG. 28 is a diagram for explaining a vehicle including the battery pack 300 of FIG. 27 .

Referring to FIG. 28 , a vehicle V according to an embodiment of the present invention includes a battery pack 300 according to an embodiment of the present invention. The vehicle V operates by receiving power from the battery pack 300 according to an embodiment of the present invention.

According to one aspect of the present invention, the bending target region of the uncoated region having a protruding shape along the axial direction of the electrode assembly is formed in a pattern extending along the bending direction, and the uncoated region flags of the bending target region are bent to bend the uncoated region. It is possible to improve the flatness of the surface, and it is possible to alleviate a phenomenon in which the uncoated portion is irregularly bent at the bottom of the bent surface.

According to another aspect of the present invention, by cutting a significant portion of the winding turn of the non-coated region in the peripheral area of the bending target area at the axial end of the electrode assembly to provide a passage through which the electrolyte can rapidly penetrate into the active material layer, the electrolyte impregnation is improved. can be improved

According to another aspect of the present invention, since the axial height of the electrode assembly can be reduced by cutting and bending the winding turn of the uncoated region, the energy density of the cylindrical battery can be increased accordingly.

According to another aspect of the present invention, in the process of cutting the winding turn of the uncoated portion, a plurality of uncoated flags formed in the bending target region are bent along the radial direction of the electrode assembly, resulting in a bending surface in which the uncoated flags are overlapped in several layers. After forming the region, resistance of the cylindrical battery may be reduced by welding a current collector plate to the region.

According to another aspect of the present invention, by providing an ultrasonic cutting device including a vertical cutter and a horizontal cutter, the winding turn portion of the uncoated portion can be easily cut so that the bending target region remains protruded in the axial direction of the electrode assembly. .

According to another aspect of the present invention, productivity and manufacturing cost of the electrode assembly can be reduced by providing a method for easily cutting the turn portion of the uncoated portion so that the bending target region remains protruded in the axial direction of the electrode assembly. can

According to another aspect of the present invention, by providing a high-capacity battery pack manufactured using cylindrical batteries having high energy density and low resistance, and a vehicle including the battery pack, it is possible to improve the safety of rapid charging and the efficiency of energy use.

As described above, although the present invention has been described by the limited embodiments and drawings, the present invention is not limited thereto, and the technical spirit of the present invention and the following by those skilled in the art to which the present invention belongs Of course, various modifications and variations are possible within the scope of equivalents of the claims to be described.

Claims (49)

An electrode assembly in which a positive electrode, a negative electrode, and a separator interposed therebetween are wound around one axis to define a core and an outer circumferential surface,
At least one of the positive electrode and the negative electrode includes a non-coated portion exposed to the outside of the separator along an axial direction of the electrode assembly at a long side end,
A winding turn portion of the uncoated portion is provided at one end of the electrode assembly,
The winding turn portion includes a cutting portion and a bending portion alternately disposed along the circumferential direction,
The axial height of the cut portion is smaller than the axial height of the bent portion;
The bent portion includes a plurality of uncoated flags arranged along the radial direction of the electrode assembly,
The electrode assembly, characterized in that the plurality of uncoated flags overlap along the axial direction and form a bent surface area along the radial direction of the electrode assembly.
The method of claim 1,
The electrode assembly, characterized in that the cut portion comprises a first cutting surface substantially perpendicular to the axial direction.
The method of claim 2,
The electrode assembly, characterized in that the first cutting surface is an ultrasonic cutting surface.
The method of claim 2,
An insulating coating layer is provided at the proximal end of the uncoated flag,
The axial end of the insulating coating layer extends and is exposed outside the axial end of the separator,
The electrode assembly, characterized in that the first cutting surface is spaced apart from the axial end of the insulating coating layer.
The method of claim 4,
When viewed in the axial direction, the electrode assembly, characterized in that the axial end of the insulating coating layer and the axial end of the active material layer included in the positive electrode or the negative electrode are exposed through the first cutting surface.
The method of claim 2,
The electrode assembly, characterized in that the plurality of uncoated flags protrude along the axial direction from the first cutting surface.
The method of claim 6,
The electrode assembly, characterized in that the plurality of uncoated flags are bent toward the core of the electrode assembly along a bending line spaced apart from the first cutting surface to form a bending surface area.
The method of claim 7,
The electrode assembly, characterized in that the bending length of the uncoated flag most adjacent to the core of the electrode assembly is smaller than or equal to the distance from the position of the uncoated flag to the core.
The method of claim 7,
The electrode assembly, characterized in that the first cutting surface is spaced apart from the bending surface area.
The method of claim 2,
The electrode assembly, characterized in that the bent portion comprises a second cutting surface extending along the side of the plurality of uncoated flags.
The method of claim 10,
The electrode assembly, characterized in that the second cutting surface is an ultrasonic cutting surface.
The method of claim 10,
The electrode assembly, characterized in that the second cutting surface is parallel to the axial direction.
The method of claim 10,
The electrode assembly, characterized in that the first cutting surface and the second cutting surface cross each other perpendicularly.
The method of claim 10,
The electrode assembly, characterized in that the second cutting surface is a flat surface.
The method of claim 10,
The electrode assembly, characterized in that the second cutting surface is a rounded surface.
The method of claim 15
Electrode assembly, characterized in that the eccentricity of the circular arc where the virtual plane perpendicular to the axial direction and the rounded plane meet is substantially 1.
The method of claim 16
The electrode assembly, characterized in that the center of the imaginary circle including the arc and the center of the core of the electrode assembly are opposed to each other based on the arc.
The method of claim 16
The electrode assembly, characterized in that the arc is substantially symmetric based on a straight line connecting the center of the virtual circle including the arc and the center of the core of the electrode assembly.
The method of claim 1,
The electrode assembly, characterized in that the width of the plurality of uncoated flags in the circumferential direction is substantially the same from the core side to the outer circumferential surface side of the electrode assembly.
The method of claim 1,
The electrode assembly, characterized in that the width of the plurality of uncoated flags in the circumferential direction gradually increases or decreases while going from the core side to the outer circumferential surface side of the electrode assembly.
The method of claim 1,
The cutting part includes first to nth cutting parts,
The electrode assembly, characterized in that the first to n-th cutting portions radially extend based on the center of the core of the electrode assembly.
The method of claim 21,
The electrode assembly, characterized in that the first to n-th cutting parts are arranged rotationally symmetrical with respect to the center of the core of the electrode assembly.
The method of claim 1,
The bent portion includes first to nth bent portions,
The electrode assembly, characterized in that the first to n-th bent portions radially extend based on the center of the core of the electrode assembly.
The method of claim 23
The electrode assembly, characterized in that the first to n-th bent parts are arranged rotationally symmetrical with respect to the center of the core of the electrode assembly.
The method of claim 1,
The electrode assembly, characterized in that the bending surface area includes an area in which three or more uncoated flags overlap along the axial direction.
(a) preparing an anode and a cathode having a sheet shape and having uncoated portions at long side ends;
(b) the positive electrode, the negative electrode, and the separator are laminated at least once so that the separator is interposed between the positive electrode and the negative electrode, and the positive electrode uncoated portion and the negative electrode uncoated portion are exposed opposite to each other along a short side direction of the separator. Forming an electrode-separator layered body;
(c) forming an electrode assembly by winding the electrode-separator laminate around one axis so that the turns of the positive electrode uncoated region and the turns of the negative electrode uncoated region are exposed in opposite directions along an axial direction; and
(d) cutting at least one of the winding turns of the positive electrode uncoated portion and the winding turns of the cathode uncoated portion, so that at least one bending target area remains (remains) in a protruding shape along the axial direction; forming a plurality of uncoated flags within the bending target region by doing so; and
(e) forming a bending surface area by bending a plurality of uncoated flags included in the bending target area along a radial direction of the electrode assembly;
The method according to claim 26, step (d),
a first cutting step of cutting an edge of the bending target region along an axial direction of the electrode assembly; and
and a second cutting step of cutting an area around the bending target area perpendicular to the axial direction so that the bending target area remains (remains) in a protruding shape along the axial direction. method.
The method according to claim 27, in the first cutting step,
The electrode assembly manufacturing method, characterized in that for cutting the edge of the bending target region using a vertical cutter that vibrates ultrasonically in the axial direction of the electrode assembly.
The method of claim 28
The cutting line for the edge of the bending target area is plural,
When viewed in the axial direction of the electrode assembly, the plurality of cutting lines form pairs of two and extend radially based on the center of the core of the electrode assembly.
The method of claim 28
The cutting line for the edge of the bending target area is plural,
When viewed in the axial direction of the electrode assembly, each of the plurality of cutting lines has an arc shape curved toward the center of the core of the electrode assembly.
The method according to claim 27, in the second cutting step,
By using a horizontal cutter that vibrates ultrasonically perpendicularly to the axial direction of the electrode assembly, a peripheral area of the bending target area is formed perpendicular to the axial direction so that the bending target area remains (remains) in a protruding shape along the axial direction. Electrode assembly manufacturing method, characterized in that for cutting.
The method according to claim 27, in the second cutting step,
By using a horizontal cutter rotating in a plane perpendicular to the axial direction of the electrode assembly, the peripheral area of the bending target area is cut along the axial direction so that the bending target area remains (remains) in a protruding shape along the axial direction. Electrode assembly manufacturing method characterized in that the vertical cutting.
The method according to claim 27, in the second cutting step,
By using a horizontal cutter that rotates in a plane perpendicular to the axial direction of the electrode assembly and vibrates ultrasonically along the plane, the bending target region remains (remains) in a protruding shape along the axial direction. Electrode assembly manufacturing method, characterized in that for cutting the peripheral area of the axial direction and perpendicular to.
The method according to claim 26, in the step (e),
The method of manufacturing an electrode assembly, characterized in that the plurality of uncoated flags are bent so that an area where at least three or more uncoated flags overlap along the axial direction is included in the bending surface region.

In the ultrasonic cutting device for cutting and processing the winding turn of the uncoated portion exposed to one end of an electrode assembly in which an anode and a cathode including a non-coated portion at the long side end and a separator interposed therebetween are wound around one axis,
a vertical cutter configured to ultrasonically cut edges of the plurality of bending target regions disposed in the circumferential direction of the electrode assembly along an axial direction to form a plurality of uncoated flags in the bending target region; and
and a horizontal cutter that ultrasonically cuts peripheral regions of the plurality of bending target regions perpendicularly to the axial direction to protrude the plurality of uncoated flags from the ultrasonic cutting surface along the axial direction.
The method of claim 35
The vertical cutter,
cutter body; and
Including a plurality of cutter knives coupled to the cover sea,
The plurality of cutter knives are ultrasonic cutting device, characterized in that arranged to correspond to the edge of the plurality of bending target areas.
The method of claim 35
The horizontal cutter,
cutter body; and
Including a cutter knife coupled to the cutter body,
The cutter knife is coupled to the cutter body so as to lie on a cutting plane perpendicular to the axial direction and has a shape corresponding to a winding turn area between adjacent bending target areas in the circumferential direction Ultrasonic cutting, characterized in that Device.
The method of claim 37
The winding turn area between the bent surface areas adjacent in the circumferential direction includes a portion curved toward the core of the electrode assembly,
The cutter knife is an ultrasonic cutting device, characterized in that the disk-shaped rotary knife having a radius substantially equal to the radius of curvature of the curved portion.
(a) An electrode assembly in which a positive electrode, a negative electrode, and a separator interposed therebetween are wound around one axis to define a core and an outer circumferential surface, wherein at least one of the positive electrode and the negative electrode is disposed at a long side end along an axial direction of the electrode assembly. A non-coated portion exposed to the outside of the separator, a winding turn portion of the non-coated portion at one end of the electrode assembly, a winding turn portion including a cut portion and a bent portion alternately disposed in a circumferential direction, and an axis of the cut portion The directional height is smaller than the axial height of the bent portion, and the bent portion includes a plurality of uncoated flags arranged along a radial direction of the electrode assembly, and the plurality of uncoated flags overlap along the axial direction of the electrode assembly. an electrode assembly forming a bending surface area along a radial direction;
(b) a battery housing including an open end and a closed part opposite thereto, in which the electrode assembly is accommodated through the open end, and electrically connected to the negative electrode;
(c) a sealing body sealing the open end of the battery housing;
(d) a terminal electrically connected to the anode and having a surface exposed to the outside; and
(e) a cylindrical battery comprising a current collector plate welded to said bent surface area and electrically connected to either said cell housing or said terminal.
The method of claim 39
The terminal is a rivet terminal installed in a through hole formed in a closed portion of the battery housing,
A cylindrical battery, characterized in that an insulating gasket is interposed between the rivet terminal and the through hole.
The method of claim 40
The rivet terminal is a cylindrical battery, characterized in that welded to the current collector plate.
The method of claim 41 ,
The current collecting plate,
a support including a hole;
at least one leg portion extending in a radial direction from the support portion and welded to the bent surface area;
a connecting portion provided inside the hole; and
Cylindrical battery characterized in that it comprises a bridge portion connecting the support portion and the connection portion.
The method of claim 39
Further comprising a crimping portion formed by bending the open end of the battery housing toward the core,
The sealing body includes a cap covering the open end of the battery housing and a sealing gasket interposed between the cap and the open end,
The cylindrical battery, characterized in that the crimping portion presses the sealing gasket toward the edge of the cap.
The method of claim 43
Further comprising a beading portion in a region adjacent to the open end of the battery housing,
At least a portion of an edge of the current collecting plate is interposed between the inner surface of the beading part and the sealing gasket and coupled to the inner surface of the beading part.
The method of claim 44
At least a portion of an edge of the current collecting plate is welded to an inner surface of the beading portion.
The method of claim 44
The current collecting plate,
support;
at least one leg portion extending in a radial direction from the support portion and welded to the bent surface area; and
and a housing connection part extending from the support part or the leg part toward the beading part and coupled to an inner surface of the beading part.
The method of claim 43
The cap corresponds to the terminal,
The current collecting plate,
support;
at least one leg portion extending outwardly from the support portion and welded to the bending surface area; and
A cylindrical battery comprising a lead part extending from the support part or the leg part and coupled to the cap.
A battery pack comprising the cylindrical battery according to any one of claims 39 to 47.
A vehicle comprising a battery pack according to claim 48 .

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