Cylindrical battery cell, battery pack and automobile including the same, and method for manufacturing cylindrical battery cell

Abstract

The present invention discloses a cylindrical battery cell, a battery pack including the same, and a vehicle. The cylindrical battery cell includes a jelly-roll-type electrode assembly having a structure in which a sheet-like first electrode plate, a second electrode plate, and a separator interposed between the first and second electrode plates are wound in one direction, a battery can having an open part in which the electrode assembly is housed and a partially closed part on the opposite side thereof and electrically connected to the second electrode plate, a current collector plate electrically connected to the first uncoated part, a cell terminal connected to the current collector plate through a through-hole in the closed part of the battery can, and an insulator interposed between the battery can and the current collector plate.

Description

[Technical field]

[0001] This application claims priority to Korean Patent Application No. 10-2021-0130391 filed on September 30, 2021, Korean Patent Application No. 10-2022-0002904 filed on January 7, 2022, and Korean Patent Application No. 10-2022-0089233 filed on July 19, 2022, and the contents disclosed in the specifications and drawings of such applications are incorporated into this application in their entirety.

[0002] The present invention relates to a cylindrical battery cell, a battery pack and a vehicle including the same, and a method for manufacturing the cylindrical battery cell. [Background technology]

[0003] Secondary batteries, which have high applicability to each product group and electrical properties such as high energy density, are widely used not only in portable devices but also in electric vehicles (EVs) and hybrid electric vehicles (HEVs) that are driven by electrical sources.

[0004] Such secondary batteries not only have the primary advantage of dramatically reducing the use of fossil fuels, but are also environmentally friendly as they do not produce any by-products from energy use, and are attracting attention as a new energy source for improving energy efficiency.

[0005] At present, secondary batteries such as lithium ion batteries, lithium polymer batteries, nickel cadmium batteries, nickel hydrogen batteries, nickel zinc batteries, etc. are widely used. The operating voltage of such a unit secondary battery cell is about 2.5V to 4.5V.

[0006] Therefore, when a higher output voltage is required, a battery pack is configured by connecting a plurality of battery cells in series. Alternatively, a battery pack may be configured by connecting a plurality of battery cells in parallel according to a charge / discharge capacity required for the battery pack. Therefore, the number of battery cells included in the battery pack and the electrical connection form may be variously set according to at least one of the required output voltage and charge / discharge capacity.

[0007] Meanwhile, known types of secondary battery cells include cylindrical, prismatic and pouch-type battery cells. In the case of a cylindrical battery cell, a separator, which is an insulator, is interposed between a positive electrode and a negative electrode, and the electrode is wound up to form a jelly-roll type electrode assembly, which is then inserted into a battery can together with an electrolyte to form a battery.

[0008] Here, when the battery can is connected to the negative or positive electrode (usually the negative electrode) to have polarity, insulation is also required between the battery can and the jelly roll type electrode assembly.

[0009] Meanwhile, in recent years, the application of cylindrical battery cells to electric vehicles has led to an increase in the form factor of cylindrical battery cells. That is, the diameter and height of cylindrical battery cells are increased compared to cylindrical battery cells having conventional form factors such as 18650 and 21700. The increase in form factor brings about an increase in energy density, an increase in safety against thermal runaway, and an improvement in cooling efficiency. In addition, in the case of cylindrical battery cells with an increased form factor, insulation between the battery can and the jelly-roll type electrode assembly has become even more important.

[0010] Insulators inserted into cylindrical battery cells for insulation are usually manufactured in a sheet form. However, when a sheet-type insulator is placed on a jelly-roll type electrode assembly and inserted into a battery can, the insulator may move. This may cause the insulator to move out of position, resulting in a deterioration in insulating properties and causing defects. Summary of the Invention [Problem to be solved by the invention]

[0011] The present invention has been made in light of the background of the prior art described above, and aims to provide an electrode assembly, a cylindrical battery cell, a battery pack including the same, and an automobile, in which an insulator is fixed to a battery can and does not move, so that when the jelly-roll type electrode assembly is subsequently inserted into a battery can, the insulator can be coupled to the jelly-roll type electrode assembly at an accurate position, thereby improving insulation and preventing the occurrence of defects.

[0012] Another object of the present invention is to provide a battery pack manufactured using a cylindrical battery cell having an improved structure, and a vehicle including the battery pack.

[0013] However, the technical problem to be solved by the present invention is not limited to the above-mentioned problem, and other problems will be clearly understood by those skilled in the art from the following description of the invention. [Means for solving the problem]

[0014] In order to achieve the above object, a cylindrical battery cell according to one aspect of the present invention includes a jelly-roll-type electrode assembly having a structure in which sheet-like first and second electrode plates and a separator interposed between the first and second electrode plates are wound in one direction, a battery can having an open portion in which the electrode assembly is housed and a partially closed portion opposite the open portion and electrically connected to the second electrode plate, a current collector plate electrically connected to the first uncoated portion, a cell terminal connected to the current collector plate through a through-hole in the closed portion of the battery can, and an insulator interposed between the battery can and the current collector plate.

[0015] Preferably, the first electrode plate of the electrode assembly includes a first uncoated portion at a long side end portion where an active material layer is not coated, and the first uncoated portion forms a plurality of winding turns based on a center of the electrode assembly and is exposed to the outside of the separator, and may be used as an electrode tab and electrically connected to the current collector plate.

[0016] Preferably, the insulator has a shape corresponding to a cross-sectional shape of the jelly-roll type electrode assembly.

[0017] In one embodiment, at least one protrusion may be provided on an outer circumferential surface of the insulator such that the insulator is coupled to the battery can through an interference fit when the electrode assembly is housed in the battery can.

[0018] Preferably, a plurality of the protrusions may be provided on the outer circumferential surface of the insulator at predetermined intervals.

[0019] Preferably, the protrusions are spaced apart at equal intervals on the outer periphery of the insulator.

[0020] In another embodiment, when the electrode assembly is housed in a battery can, a heat seal layer may be formed on the surface of the insulator facing the inner surface of the closing portion of the battery can so that the insulator is fixed to the battery can by heat sealing.

[0021] In yet another embodiment, when the electrode assembly is housed in a battery can, an adhesive layer may be formed on an upper surface of the insulator in contact with the battery can so that the insulator is fixed to the battery can by adhesion.

[0022] In yet another embodiment, the insulator may be fixed to the battery can by double-sided tape.

[0023] Preferably, at least one through hole through which an electrolyte can move may be formed on an upper surface of the insulator connected to an outer circumferential surface of the insulator.

[0024] Preferably, a plurality of the through holes may be formed, and the plurality of the through holes may be spaced apart at a predetermined interval.

[0025] Preferably, a plurality of through holes may be arranged on a straight line extending from a center of the insulator toward an outer circumferential surface of the insulator.

[0026] Preferably, a plurality of through holes may be arranged on each of a plurality of straight lines radially arranged from a center of the insulator toward an outer circumferential surface of the insulator.

[0027] Desirably, the arrangement intervals of the plurality of through holes may increase or decrease along the radial direction.

[0028] Preferably, the through hole has a diameter of 1.0 mm to 3.0 mm.

[0029] In one form, the distance from the center of the insulator to the end of the protrusion may be greater than the radius of the electrode assembly.

[0030] In another embodiment, the distance from the center of the insulator to the end of the protrusion can be greater than the inner diameter of the battery can.

[0031] Desirably, the peripheral edge of the insulator may have a cross-sectional shape that corresponds to the cross-sectional shape of the edge of the closure of the battery can.

[0032] Preferably, the thickness of the insulator may correspond to the distance between the inner surface of the closure of the battery can and the current collector plate.

[0033] Preferably, the thickness of the insulator may be 0.8 mm or more and 1.6 mm or less.

[0034] In one embodiment, an upper portion of the insulator may contact an inner surface of the closure of the battery can, and a lower portion of the insulator may contact an upper surface of the current collector plate.

[0035] Desirably, the insulator may comprise an insulating polymeric material.

[0036] Preferably, the insulator is made of polyethylene terephthalate (PET), polybutylene terephthalate (PBT) or polypropylene (PP), or may be made by adding at least one of a heat-resistant additive and a flame retardant to polyethylene terephthalate (PET), polybutylene terephthalate (PBT) or polypropylene (PP).

[0037] Preferably, the insulator is made of an elastic material.

[0038] Preferably, the insulator has a central hole having a preset diameter at a center thereof, and a lower portion of the cell terminal may be exposed from the central hole.

[0039] Preferably, an insulating tape may be attached to an outer periphery of the electrode assembly at least up to a point corresponding to a periphery of the insulator.

[0040] In one embodiment, at least a portion of the first uncoated portion may be divided into a plurality of segments along a winding direction of the electrode assembly.

[0041] In another embodiment, the plurality of segments may be folded along a radial direction of the electrode assembly.

[0042] In yet another embodiment, the plurality of segments may overlap in multiple layers along a radial direction of the electrode assembly.

[0043] Preferably, the battery can has a closed portion and an open portion positioned opposite each other, and may further include a cap plate configured to seal the open portion of the battery can.

[0044] Preferably, the battery can may include a sealing gasket interposed between a periphery of the cap plate and the opening of the battery can, the battery can may include a beading portion pressed into the inside of the battery can in an area adjacent to the opening, and the battery can may include a crimping portion that extends into the inside of the battery can and is bent to wrap around and fix the periphery of the cap plate together with the sealing gasket.

[0045] Preferably, the crimping portion may be formed at a lower portion of the battery can based on a placement state of the battery can.

[0046] Preferably, the cap plate includes a venting notch that ruptures when the internal pressure of the battery can exceeds a critical value.

[0047] Preferably, the venting notches may be formed on both sides of the cap plate and may be formed in at least one of a continuous circular pattern, a discontinuous circular pattern, and a linear pattern on the surface of the cap plate.

[0048] Preferably, the venting notch is formed at a lower portion of the battery can based on the arrangement of the battery can, and when the venting notch is ruptured, gas inside the battery can can be discharged from the lower side of the battery can.

[0049] Preferably, the width of the bent portion of the insulating tape may be 3 mm to 10 mm.

[0050] Preferably, the insulating tape includes a polyimide resin layer.

[0051] The above object is also achieved by a battery pack including at least one cylindrical battery cell as described above, and a vehicle including at least one such battery pack.

[0052] In order to achieve the above object, a manufacturing method of a cylindrical battery cell according to another aspect of the present invention includes the steps of: (a) preparing a jelly-roll-type electrode assembly having a structure in which sheet-like first and second electrode plates and a separator interposed between the first and second electrode plates are wound in one direction; (b) coupling a current collector to a first uncoated portion of the electrode assembly; (c) preparing a battery can having an open portion in which the electrode assembly is housed and a partially closed portion opposite the open portion, the battery can being electrically connected to the second electrode plate; (d) coupling a cell terminal through a through-hole in a closed portion of the battery can; (e) coupling an insulator to an inner surface of the closed portion of the battery can; and (f) inserting the electrode assembly into the battery can to interpose the insulator between the battery can and the current collector.

[0053] Preferably, step (a) may include a step in which the first electrode plate of the electrode assembly includes a first uncoated portion at a long side end portion where an active material layer is not coated, the first uncoated portion forming a plurality of winding turns based on a center of the electrode assembly, being exposed to the outside of the separator, and being used as an electrode tab and electrically connected to the current collector plate.

[0054] In one embodiment, the insulator may have at least one protrusion on an outer circumferential surface thereof, and step (e) may include coupling the insulator to the battery can through an interference fit.

[0055] Preferably, the protrusions are provided in a plurality of numbers, the plurality of protrusions being provided at predetermined intervals on the outer circumferential surface of the insulator, and in step (e), the protrusions may be crimped through an interference fit.

[0056] In another embodiment, the insulator has a heat seal layer on a surface facing the inner surface of the closure of the battery can, and step (e) may include fixing the insulator to the battery can by heat sealing.

[0057] In yet another embodiment, an adhesive layer is provided on an upper surface of the insulator that contacts the battery can, and step (e) may include a step of adhesively fixing the insulator to the battery can.

[0058] In yet another embodiment, step (e) may include fixing the insulator to the battery can with double-sided tape.

[0059] In still another embodiment, the method may further include (g) injecting an electrolyte while the battery can is held upright so that the cell terminal faces the direction of gravity.

[0060] Preferably, at least one through hole is provided on an upper surface of the insulator connected to an outer circumferential surface of the insulator, and in step (g), the electrolyte may move into the electrode assembly through the through hole.

[0061] Preferably, at least one through hole may be formed in an upper surface of the insulator connected to an outer circumferential surface of the insulator, and an electrolyte may move through the through hole.

[0062] Preferably, a plurality of the through holes may be formed, and the plurality of the through holes may be spaced apart at a predetermined interval.

[0063] Preferably, a plurality of through holes may be arranged on a straight line extending from a center of the insulator toward an outer circumferential surface of the insulator.

[0064] Preferably, a plurality of through holes may be arranged on each of a plurality of straight lines radially arranged from a center of the insulator toward an outer circumferential surface of the insulator. Effect of the Invention

[0065] According to one aspect of the present invention, the insulator is fixed to the battery can and does not move. Therefore, when the jelly-roll type electrode assembly is subsequently inserted into the battery can, the insulator can be coupled to the jelly-roll type electrode assembly at an accurate position, thereby improving insulation and preventing defects.

[0066] According to one embodiment of the present invention, a battery pack having an improved capacity using a cylindrical battery cell having an improved structure, and a vehicle including the battery pack can be provided.

[0067] The following drawings attached to this specification illustrate preferred embodiments of the present invention and, together with the detailed description of the invention, serve to further understand the technical ideas of the present invention. Therefore, the present invention should not be interpreted as being limited to only the matters described in the drawings. [Brief description of the drawings]

[0068] [Figure 1] FIG. 1 is a perspective view of a cylindrical battery cell according to one embodiment of the present invention. [Diagram 2] FIG. 2 is a cross-sectional perspective view showing a central portion of the cylindrical battery cell of FIG. 1. [Diagram 3] FIG. 2 is a cross-sectional view of a cylindrical battery cell according to one embodiment of the present invention. [Figure 4] FIG. 2 is a perspective view of an insulator in a cylindrical battery cell according to one embodiment of the present invention. [Diagram 5] 5 is a variation of the insulator of FIG. 4. [Figure 6] 5 is a variation of the insulator of FIG. 4. [Figure 7] 5 is a variation of the insulator of FIG. 4. [Figure 8] FIG. 2 is a diagram showing a battery can in a cylindrical battery cell according to one embodiment of the present invention. [Figure 9] FIG. 2 is an enlarged view of a cell terminal in a cylindrical battery cell according to one embodiment of the present invention. [Figure 10] FIG. 4 is a cross-sectional view of another embodiment of the cylindrical battery cell of FIG. [Figure 11] FIG. 2 is a plan view showing a structure of an electrode plate according to an embodiment of the present invention. [Figure 12] FIG. 12 is a diagram showing the definitions of the width, height and separation pitch of the segments in FIG. [Figure 13] FIG. 13 is a plan view showing a structure of an electrode plate according to another embodiment of the present invention. [Figure 14] FIG. 14 is a diagram showing the definitions of the width, height and separation pitch of the segments in FIG. [Figure 15] 1 is a cross-sectional view of an electrode assembly according to an embodiment of the present invention taken along the Y-axis (winding axis) direction. [Figure 16] 6 is a cross-sectional view of an electrode assembly according to another embodiment of the present invention taken along the Y-axis (winding axis) direction. [Figure 17] 1 is a diagram illustrating a schematic configuration of a battery pack according to an embodiment of the present invention; [Figure 18] FIG. 18 is a diagram for explaining a car including the battery pack of FIG. 17. [Figure 19] 1A to 1C are diagrams illustrating a process for manufacturing a cylindrical battery cell according to an embodiment of the present invention. [Figure 20] 1A to 1C are diagrams illustrating a process for manufacturing a cylindrical battery cell according to an embodiment of the present invention. [Figure 21] 1A to 1C are diagrams illustrating a process for manufacturing a cylindrical battery cell according to an embodiment of the present invention. [Figure 22] 1A to 1C are diagrams illustrating a process for manufacturing a cylindrical battery cell according to an embodiment of the present invention. [Figure 23] 1A to 1C are diagrams illustrating a process for manufacturing a cylindrical battery cell according to an embodiment of the present invention. [Figure 24] 1A to 1C are diagrams illustrating a process for manufacturing a cylindrical battery cell according to an embodiment of the present invention. [Diagram 25] 1A to 1C are diagrams illustrating a process for manufacturing a cylindrical battery cell according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0069] Hereinafter, a preferred embodiment of the present invention will be described in detail with reference to the attached drawings. Prior to this, the terms and words used in the present specification and claims are not to be construed as being limited to their ordinary and dictionary meanings, but are to be construed as having meanings and concepts corresponding to the technical ideas of the present invention, in accordance with the principle that the inventors themselves can appropriately define the concepts of terms in order to best describe the invention.

[0070] Therefore, it should be understood that the embodiment described in this specification and the configurations shown in the drawings are merely the most preferred embodiment of the present invention and do not represent the entire technical idea of ​​the present invention, and therefore there may be various equivalents and modifications that can be substituted therefor at the time of this application.

[0071] In addition, in order to facilitate understanding of the invention, the accompanying drawings may not be drawn to scale, and the dimensions of some components may be exaggerated. In addition, the same reference numerals may be used to refer to the same components in different embodiments.

[0072] FIG. 1 is a perspective view of a cylindrical battery cell according to one embodiment of the present invention, FIG. 2 is a cross-sectional perspective view showing the center of the cylindrical battery cell of FIG. 1, FIG. 3 is a cross-sectional view of a cylindrical battery cell according to one embodiment of the present invention, FIG. 4 is a perspective view of an insulator in a cylindrical battery cell according to one embodiment of the present invention, FIGS. 5 to 7 are modified forms of the insulator of FIG. 4, FIG. 8 is a view showing a battery can in a cylindrical battery cell according to one embodiment of the present invention, FIG. 9 is an enlarged view of a cell terminal in a cylindrical battery cell according to one embodiment of the present invention, and FIG. 10 is a cross-sectional view of another embodiment of the cylindrical battery cell of FIG. 3.

[0073] A cylindrical battery cell 10 according to one embodiment of the present invention will now be described.

[0074] Desirably, the cylindrical battery cell 10 may be, for example, a cylindrical battery cell 10 having a form factor ratio (defined as the diameter divided by the height of the cylindrical battery cell, i.e., the ratio of height (H) to diameter (Φ)) greater than about 0.4.

[0075] Here, the form factor refers to a value indicating the diameter and height of a cylindrical battery cell 10. The cylindrical battery cell 10 according to an embodiment of the present invention may be, for example, a 46110 cell, a 48750 cell, a 48110 cell, a 48800 cell, or a 46800 cell. In the numerical value indicating the form factor, the first two digits indicate the diameter of the cell, the following two digits indicate the height of the cell, and the last digit 0 indicates that the cross section of the cell is circular. When the height of the cell exceeds 100 mm, the last digit can be omitted since three digits are needed to indicate the height.

[0076] A battery cell according to one embodiment of the present invention may be a cylindrical battery cell 10 that is a generally cylindrical cell having a diameter of about 46 mm, a height of about 110 mm, and a form factor ratio of 0.418.

[0077] A battery cell according to another embodiment may be a cylindrical battery cell 10 that is a generally cylindrical cell having a diameter of about 48 mm, a height of about 75 mm, and a form factor ratio of 0.640.

[0078] A battery cell according to yet another embodiment may be a cylindrical battery cell 10 that is a generally cylindrical cell having a diameter of about 48 mm, a height of about 110 mm, and a form factor ratio of 0.418.

[0079] A battery cell according to yet another embodiment may be a cylindrical battery cell 10 that is a generally cylindrical cell having a diameter of about 48 mm, a height of about 80 mm, and a form factor ratio of 0.600.

[0080] A battery cell according to yet another embodiment may be a cylindrical battery cell 10 that is a generally cylindrical cell having a diameter of about 46 mm, a height of about 80 mm, and a form factor ratio of 0.575.

[0081] Conventionally, battery cells with a form factor ratio of about 0.4 or less have been used. That is, conventionally, for example, 18650 cells, 21700 cells, etc. have been used. In the case of 18650 cells, the diameter is about 18 mm, the height is about 65 mm, and the form factor ratio is 0.277. In the case of 21700 cells, the diameter is about 21 mm, the height is about 70 mm, and the form factor ratio is 0.300.

[0082] 2 and 3, a cylindrical battery cell 10 according to an embodiment of the present invention includes an electrode assembly 100, a cylindrical battery can 200, a current collector 300, a cell terminal 400, and an insulator 600. Here, reference numeral 500 denotes an insulating tape 500 for insulating a side surface of the electrode assembly 100 as described below, and the insulating tape 500 can prevent contact between the current collector 300 and the battery can 200. The insulating tape 500 may cover at least an upper outer peripheral surface of the electrode assembly 100. Here, the width of the bent portion of the insulating tape 500 may be 3 mm to 10 mm. And, the insulating tape 500 may include a polyimide-based resin layer.

[0083] The electrode assembly 100 is provided such that the first and second electrode plates in sheet form are wound in one direction with a separator interposed therebetween. That is, the electrode assembly 100 is a jelly roll type having a structure in which the first and second electrode plates in sheet form and the separator interposed between the first and second electrode plates are wound in one direction. The first electrode plate may have a positive polarity or a negative polarity, and the second electrode plate has a polarity opposite to that of the first electrode plate. That is, the first electrode plate may be a positive electrode plate or a negative electrode plate, and the second electrode plate may be a negative electrode plate or a positive electrode plate having a polarity opposite to that of the first electrode plate. However, for convenience of explanation, the following description will be centered on the case where the first electrode plate is a positive electrode plate and the second electrode plate is a negative electrode plate. Meanwhile, the detailed description of the electrode assembly 100 is substituted for the above description.

[0084] The electrode assembly 100 may be configured in various jelly roll shapes and may be modified. For example, the electrode assembly 100 may have a non-coated portion formed thereon, and the non-coated portion itself may be used as an electrode tab, or electrode tabs of various shapes may be connected to the non-coated portion in various ways. For convenience of explanation, the following description will focus on an embodiment in which the non-coated portion itself is used as an electrode tab, but the electrode assembly 100 may be modified in various ways.

[0085] 3, the first electrode plate may include a first uncoated portion 110 at a long side end where an active material layer is not coated, and the second electrode plate may also include a second uncoated portion 120 at a long side end where an active material layer is not coated, that is, at least one of the first and second electrode plates may include a uncoated portion at a long side end in the winding direction where an active material is not coated.

[0086] Here, the first uncoated portion 110 and the second uncoated portion 120 form a plurality of winding turns based on the center of the electrode assembly 100, are exposed to the outside of the separator, and are used as electrode tabs themselves.

[0087] The electrode assembly 100 may be coupled with the insulator 600 described above. Preferably, the insulator 600 is configured to cover an upper end of the first uncoated portion 110 for insulation. The insulator 600 prevents contact between the first uncoated portion 110 and the battery can 200. In the case of FIG. 3, the current collecting plate 300 is coupled to the upper side of the first uncoated portion 110, and the insulator 600 is coupled to the upper side of the current collecting plate 300. That is, the insulator 600 is accommodated inside the battery can 200, covers at least a portion of the electrode assembly 100, and is configured to cut off electrical connection between the first uncoated portion 110 and the battery can 200. Here, when the current collecting plate 300 is provided on the upper side of the first uncoated portion 110, the insulator 600 is coupled to the current collecting plate 300 on the upper side of the current collecting plate 300 to cut off electrical connection between the battery can 200 and the current collecting plate 300. Therefore, the insulator 600 may be made of a material having insulating properties. Preferably, the insulator 600 may include, but is not limited to, an insulating polymer material. For example, the insulator 600 may be made of polyethylene terephthalate (PET), polybutylene terephthalate (PBT), or polypropylene (PP). As another example, the insulator 600 may be made by adding at least one of a heat-resistant additive and a flame retardant to polyethylene terephthalate (PET), polybutylene terephthalate (PBT), or polypropylene (PP). Here, the heat-resistant additive may include mica or glass fiber.

[0088] The insulator 600 is interposed between the battery can 200 and the current collecting plate 300 to cover an upper end of the first uncoated portion 110. The insulator 600, together with the insulating tape 500, can prevent contact between the first uncoated portion 110 and the battery can 200 and between the current collecting plate 300 and the battery can 200. That is, the insulator 600 prevents contact between the upper side of the first uncoated portion 110 and the battery can 200 or between the current collecting plate 300 and the battery can 200, and the insulating tape 500 prevents contact between a side surface of the electrode assembly 100 and the battery can 200. In particular, the insulating tape 500 can prevent contact between a side surface of the first uncoated portion 110 and the battery can 200.

[0089] The insulator 600 may be formed in a shape corresponding to the cross-sectional shape of the jelly roll type electrode assembly 100. For example, if the cross-section of the jelly roll type electrode assembly 100 is circular, the insulator 600 may also be circular.

[0090] The insulator 600 may be coupled to the battery can 200 in various ways. In one example, the insulator 600 may be coupled to the battery can 200 through an interference fit before the electrode assembly 100 is housed in the battery can 200. For example, referring to FIG. 4, at least one protrusion 610 may be formed on the outer circumferential surface of the insulator 600.

[0091] Preferably, a plurality of protrusions 610 may be provided, and the plurality of protrusions 610 may be formed at a predetermined interval on the outer circumferential surface of the insulator 600. Although four protrusions 610 are formed in Fig. 4, the present invention is not limited to this. When four protrusions 610 are formed, the four protrusions 610 may be formed at equal intervals on the outer circumferential surface of the insulator 600. When the insulator 600 having the protrusions 610 formed on its outer circumferential surface is coupled to the battery can 200, the protrusions 610 may be compressed and deformed, and the insulator 600 may be coupled to the inner surface of the battery can 200 in a press-fit manner.

[0092] Desirably, the distance from the center of the insulator 600 to the end of the protrusion 610 may be greater than the radius of the electrode assembly 100. Alternatively, the distance from the center of the insulator 600 to the end of the protrusion 610 may be greater than the inner diameter of the battery can 200. Thus, when the insulator 600 is inserted into the battery can 200, the protrusion 610 may be crimped and the insulator 600 may be coupled to the battery can 200 in an interference fit manner.

[0093] In another example, a heat-sealing layer may be formed on the insulator 600 so that the insulator 600 is fixed to the battery can 200 by heat fusion. That is, before the electrode assembly 100 is housed in the battery can 200, the insulator 600 may be inserted into the battery can 200 and then fixed by heat fusion using hot air spray or heating.

[0094] In yet another example, an adhesive layer may be formed on the upper surface of the insulator 600 that contacts the battery can 200 so that the insulator 600 is fixed to the battery can 200 by adhesion. That is, before the electrode assembly 100 is housed in the battery can 200, the insulator 600 may be bonded to the battery can 200 by an adhesive layer formed on the upper surface of the insulator 600.

[0095] In yet another example, the insulator 600 may be fixed to the battery can 200 by double-sided tape. Here, when the insulator 600 is fixed to the battery can 200 by thermal fusion, adhesion, or double-sided tape, the protrusion 610 on the outer circumferential surface of the insulator 600 as shown in FIG. 5 is not required.

[0096] In this manner, when the electrode assembly 100 is inserted into the battery can 200 with the insulator 600 fixed to the battery can 200, the insulator 600 is coupled to the correct position of the jelly roll-type electrode assembly 100, thereby improving the insulation properties of the cylindrical battery cell and preventing the occurrence of defects.

[0097] The insulator 600 may have a thickness of 0.8 mm or more and 1.6 mm or less. If the insulator 600 is too thin, the insulating properties may be reduced. Also, if the insulator 600 is too thick, it occupies too much of the internal space of the battery can 200, reducing the capacity of the battery cell and increasing costs. Therefore, in order to prevent the capacity of the battery cell from decreasing while maintaining appropriate insulating properties, the insulator 600 may have a thickness of 0.8 mm or more and 1.6 mm or less, preferably 1.0 mm to 1.4 mm. However, the thickness of the insulator 600 is not limited thereto.

[0098] 4, at least one through-hole 620 through which the electrolyte can move may be formed on an upper surface of the insulator 600 connected to an outer circumferential surface of the insulator 600. Here, when the electrolyte is injected into the battery can 200, the insulator 600 may be disposed facing the bottom. That is, the electrolyte may be injected into the battery can 200 in a state in which the cylindrical battery cell 10 of FIG. 3 is turned upside down, i.e., the cell terminal 400 is disposed on the lower side.

[0099] 7, the electrolyte passes through the center of the insulator 600 and moves downward in the direction of arrow a1 (the direction in which the electrolyte is injected), then moves in the direction of arrow a2 at the bottom of the insulator 600, and then moves upward in the direction of arrow a3 through the through-hole 620, thereby providing the electrolyte to the electrode assembly 100. At this time, if the through-hole 620 is formed in the insulator 600, the electrolyte can be provided to the electrode assembly 100 smoothly and easily.

[0100] A plurality of through holes 620 may be formed, and the plurality of through holes 620 may be spaced apart at a preset interval. Referring to Fig. 4, the plurality of through holes 620 may be arranged on one straight line extending from the center of the insulator 600 toward the outer circumferential surface of the insulator 600. In Figs. 4 and 7, three through holes 620 are arranged on each of a plurality of straight lines extending radially from the center of the insulator 600 toward the outer circumferential surface of the insulator 600, but the number, shape and / or arrangement of the through holes 620 are not limited thereto.

[0101] Referring to FIG. 5 as a modified example, the diameters of the through holes 620 arranged in the radial direction of the insulator 600 may be the same or may vary. As an example, the diameters of the through holes 620 may be equal, increase, or decrease from the center to the periphery. Since the electrolyte moves from the center to the periphery of the insulator 600, the amount of electrolyte movement in the direction of the arrow a3 may be greater closer to the center of the insulator 600. Therefore, the through holes 620 may be made larger toward the periphery of the insulator 600 to adjust the overall amount of electrolyte movement to be equal. However, the through holes 620 may be made smaller toward the periphery of the insulator 600 as necessary.

[0102] 6, for another variation, the spacing between the through holes 620 may be the same or may vary in the radial direction of the insulator 600. As an example, the through holes 620 may be spaced more or less apart from the center to the periphery.

[0103] Here, the diameter of the through hole may be 1.0 mm to 3.0 mm, and preferably 1.2 mm to 1.7 mm.

[0104] The periphery of the insulator 600 may have a cross-sectional shape that corresponds to the cross-sectional shape of the edge of the closure portion 210 of the battery can 200. As an example, if the edge of the closure portion 210 of the battery can 200 has a rounded cross-section, the periphery of the insulator 600 may also be formed in a rounded shape to correspond to the rounded cross-section of the edge of the closure portion 210 of the battery can 200.

[0105] Desirably, the insulator 600 may have a thickness corresponding to the distance between the inner surface of the closure portion 210 of the battery can 200 and the current collector plate 300. As an example, an upper portion of the insulator 600 may contact the inner surface of the closure portion 210 of the battery can 200, and a lower portion of the insulator 600 may contact the upper surface of the current collector plate 300. Desirably, the insulator 600 may have a thickness of 0.8 mm or more and 1.6 mm or less.

[0106] The insulator 600 may include, for example, a material having elasticity. Therefore, when vibration or external impact is applied to the cylindrical battery cell 10, the insulator 600 can absorb the impact in the process of being compressed by elasticity and then returning to its original state. As a result, even if vibration or external impact is applied to the battery cell, damage to the internal components of the battery cell can be minimized.

[0107] The insulator 600 may have a central hole having a preset diameter at the center, and the lower portion of the cell terminal 400 may be exposed from the central hole. For example, the insulator 600 may have a substantially circular central hole adjacent to the winding center. The presence of the central hole allows the cell terminal 400 to come into contact with the current collecting plate 300 or the first uncoated portion 110. Preferably, the central hole has a diameter that allows the lower portion of the cell terminal 400 to be exposed.

[0108] The insulating tape 500 may be attached to the outer circumferential surface of the electrode assembly 100 at least up to a point corresponding to the periphery of the insulator 600. The insulating tape 500 may be a double-sided tape or a single-sided tape. However, the present invention is not limited to the insulating tape, and a heat shrink tube may be attached to the outer circumferential surface of the electrode assembly 100.

[0109] The first electrode plate has a first electrode active material applied to one or both sides thereof, and a first uncoated portion 110 where the first electrode active material is not applied exists at an end of the first electrode plate.

[0110] The second electrode plate has a second electrode active material applied to one or both sides thereof, and a second uncoated portion 120 where the second electrode active material is not applied exists at an end of the second electrode plate.

[0111] The first uncoated portion 110 of the first electrode plate and the second uncoated portion 120 of the second electrode plate are arranged to face in opposite directions when wound up as an electrode assembly. The first uncoated portion 110 extends toward the closed portion 210 of the battery can 200, and the second uncoated portion 120 extends toward the open portion 220 of the battery can 200.

[0112] In the present invention, the positive active material coated on the positive electrode plate and the negative active material coated on the negative electrode plate may be any active material known in the art without any limitations.

[0113] As an example, the positive electrode active material can be represented by the general chemical formula A[A x M y ]O 2+z (A includes at least one element of Li, Na, and K; M includes at least one element selected from Ni, Co, Mn, Ca, Mg, Al, Ti, Si, Fe, Mo, V, Zr, Zn, Cu, Al, Mo, Sc, Zr, Ru, and Cr; x≧0, 1≦x+y≦2, −0.1≦z≦2; the stoichiometric coefficients x, y, and z are selected to maintain electrical neutrality of the compound).

[0114] As another example, the positive electrode active material is an alkali metal compound xLiM disclosed in U.S. Patent No. 6,677,082, U.S. Patent No. 6,680,143, etc. 1 O2-(1-x)Li2M 2 O3 (M 1 contains at least one element having an average oxidation state of 3; M 2 contains at least one element having an average oxidation state of 4; 0 ≦ x ≦ 1).

[0115] As still another example, the positive electrode active material has the general chemical formula Li a M 1 x Fe 1-x M 2 y P 1-y M 3 z O 4-z (M 1 contains at least one element selected from Ti, Si, Mn, Co, Fe, V, Cr, Mo, Ni, Nd, Al, Mg, and Al; M 2 contains at least one element selected from Ti, Si, Mn, Co, Fe, V, Cr, Mo, Ni, Nd, Al, Mg, Al, As, Sb, Si, Ge, V, and S; M 3 contains a halogen group element selectively containing F; 0 < a ≦ 2, 0 ≦ x ≦ 1, 0 ≦ y < 1, 0 ≦ z < 1; the stoichiometric coefficients a, x, y, and z are selected so that the compound maintains electrical neutrality), or lithium metal phosphate represented by Li3M2(PO4)3 [M contains at least one element selected from Ti, Si, Mn, Fe, Co, V, Cr, Mo, Ni, Al, Mg, and Al].

[0116] Desirably, the positive electrode active material may include primary particles and / or secondary particles formed by aggregation of primary particles.

[0117] In one example, the negative electrode active material may be a carbon material, lithium metal or a lithium metal compound, silicon or a silicon compound, tin or a tin compound, etc. Metal oxides such as TiO2 and SnO2 having a potential of less than 2 V may also be used as the negative electrode active material. The carbon material may be either low-crystalline carbon or high-crystalline carbon.

[0118] The separator may be a porous polymer film, for example, a porous polymer film made of a polyolefin polymer such as an ethylene homopolymer, a propylene homopolymer, an ethylene / butene copolymer, an ethylene / hexene copolymer, an ethylene / methacrylate copolymer, etc., used alone or in combination. As another example, the separator may be a conventional porous nonwoven fabric, for example, a nonwoven fabric made of a high melting point glass fiber, a polyethylene terephthalate fiber, etc.

[0119] At least one surface of the separation membrane may include a coating layer of inorganic particles. Alternatively, the separation membrane itself may be made of a coating layer of inorganic particles. The particles constituting the coating layer may have a structure in which they are bound with a binder such that there is an interstitial volume between adjacent particles.

[0120] The inorganic particles may be made of an inorganic material having a dielectric constant of 5 or more. As a non-limiting example, the inorganic particles may be made of Pb(Zr,Ti)O3 (PZT), Pb 1-x La x Zr 1-y Ti y O3(PLZT), PB(Mg3Nb 2 / 3 )O3-PbTiO3 (PMN-PT), BaTiO3, hafnia (HfO2), SrTiO3, TiO2, Al2O3, ZrO2, SnO2, CeO2, MgO, CaO, ZnO, and Y2O3.

[0121] The electrolyte is A + B - In this case, the salt may have the structure: +Li + , Na + , K + or a combination thereof. - F - , Cl - , Br - , I - , NO3 - , N(CN)2 - , BF4 - , ClO4 - , AlO4 - , AlCl4 - , PF6 - , SbF6 - , AsF6 - , BF2C2O4 - , BC4O8 - , (CF3)2PF4 - , (CF3)3PF3 - , (CF3)4PF2 - , (CF3)5PF - , (CF3)6P - , CF3SO3 - , C4F9SO3 - , CF3CF2SO3 - , (CF3SO2)2N - , (FSO2)2N - , CF3CF2(CF3)2CO - , (CF3SO2)2CH - , (SF5)3C - , (CF3SO2)3C - , CF3(CF2)7SO3, CF3CO2 - , CH3CO2 - , SCN - and (CF3CF2SO2)2N - The anion includes one or more anions selected from the group consisting of:

[0122] The electrolyte may be dissolved in an organic solvent for use. The organic solvent may be propylene carbonate (PC), ethylene carbonate (EC), diethyl carbonate (DEC), dimethyl carbonate (DMC), dipropyl carbonate (DPC), dimethyl sulfoxide, acetonitrile, dimethoxyethane, diethoxyethane, tetrahydrofuran, N-methyl-2-pyrrolidone (NMP), ethyl methyl carbonate (EMC), γ-butyrolactone, or a mixture thereof.

[0123] The battery can 200 is cylindrical, houses the electrode assembly 100, and is electrically connected to the second electrode plate of the electrode assembly 100. Thus, the battery can 200 can have the same polarity as the second electrode plate. That is, when the second electrode plate has a negative polarity, the battery can 200 also has a negative polarity.

[0124] If the size of the electrode assembly 100 is increased while the size of the battery can 200 is determined according to the standard, the overall capacity of the battery cell increases while the gap between the battery can 200 and the electrode assembly 100 decreases.

[0125] That is, if the size of the electrode assembly 100 is increased to increase the overall capacity of the battery cell, the gap between the battery can 200 and the electrode assembly 100 decreases. Therefore, in order to increase the capacity of the battery cell, the insulator 600 must be interposed in the reduced gap between the battery can 200 and the electrode assembly 100. For this reason, it is desirable for the thickness of the insulator 600 to be as thin as possible.

[0126] Referring to FIG. 8, a battery can 200 may have a closed portion 210 and an open portion 220 formed opposite each other.

[0127] 8, for example, an opening 220 may be formed at the bottom of the battery can 200. The battery can 200 accommodates the electrode assembly 100 through the opening 220 formed at the bottom, and the electrolyte is also injected through the opening 220 formed at the bottom of the battery can 200. When injecting the electrolyte, the battery can 200 may be turned upside down so that the opening 220 faces upward.

[0128] That is, the battery can 200 is a substantially cylindrical container having an opening 220 formed at the bottom, and is made of a conductive material such as a metal. The material of the battery can 200 may be a conductive metal such as aluminum, steel, stainless steel, etc., but is not limited thereto. Optionally, a Ni coating layer may be formed on the surface of the battery can 200.

[0129] 8, a closing part 210 may be formed on an upper part of a battery can 200. A through hole 211 may be formed in the closing part 210, and a cell terminal 400 may be coupled to the through hole 211 as shown in FIG.

[0130] A beading portion 240 and a crimping portion 250 may be formed at the bottom of the battery can 200. The beading portion 240 is formed by pressing the periphery of the battery can 200 inward in a region adjacent to the opening 220 of the battery can 200.

[0131] The beading portion 240 supports the electrode assembly 100, which has a size approximately corresponding to the width of the battery can 200, so that the electrode assembly 100 does not slip out of the opening 220 formed at the bottom of the battery can 200, and may also function as a support on which the cap plate 230 is placed. In addition, the beading portion 240 supports the outer circumferential surface of the sealing gasket 260.

[0132] The crimping part 250 is extended and bent toward the inside of the battery can 200 to wrap and fix the periphery of the cap plate 230 together with the sealing gasket 260. Here, the crimping part 250 is formed at the lower part of the battery can 200 based on the arrangement state of the battery can 200. For example, when the battery can 200 is arranged so that the cell terminal 400 is located at the upper part as shown in Fig. 3, the crimping part 250 is formed at the lower part of the battery can 200 based on Fig. 3. And, as shown in Fig. 3, the crimping part 250 is formed at the lower part of the beading part 240.

[0133] However, the present invention does not exclude a case where the battery can 200 does not include at least one of the beading portion 240 and the crimping portion 250. In the present invention, when the battery can 200 does not include at least one of the beading portion 240 and the crimping portion 250, the fixing of the electrode assembly 100, the fixing of the cap plate 230, or the sealing of the battery can 200 can be achieved through at least one of additional application of a component that can function as a stopper for the electrode assembly 100, additional application of a structure on which the cap plate 230 can be placed, and welding of the battery can 200 and the cap plate 230.

[0134] 3, the crimping portion 250 is formed under the beading portion 240. The crimping portion 250 is extended and bent to surround the periphery of the cap plate 230 disposed under the beading portion 240. The cap plate 230 is fixed on the beading portion 21 according to the shape of the bent crimping portion 250. Of course, the crimping portion 250 may be omitted and the cap plate 230 may be fixed while covering the opening of the battery can 200 through another fixing structure. For example, Korean Patent Publication No. 10-2019-0030016 by the present applicant discloses a cylindrical battery cell in which a beading portion is omitted, and such a structure may be adopted in the present invention.

[0135] The current collecting plate 300 is electrically connected to the first electrode plate on the upper part of the electrode assembly 100. The current collecting plate 300 is made of a conductive metal material and is connected to the first uncoated portion 110 of the electrode assembly 100.

[0136] The current collecting plate 300 may be coupled to an upper portion of a coupling surface formed by bending an end of the first uncoated portion 110 in a direction parallel to the current collecting plate 300. The bending direction of the first uncoated portion 110 may be, for example, a direction toward the winding center of the electrode assembly 100.

[0137] When the first uncoated portion 110 has such a folded shape, the space occupied by the first uncoated portion 110 is reduced, thereby improving the energy density. Also, the bonding area between the first uncoated portion 110 and the current collecting plate 300 is increased, thereby improving the bonding strength and reducing the resistance.

[0138] The cell terminal 400 is made of a conductive metal material (e.g., aluminum) and is coupled to a through-hole 211 formed in a closing portion 210 of the battery can 200, thereby electrically connecting with the current collector plate 300. The cell terminal 400 is electrically connected to the first electrode plate of the electrode assembly 100 through the current collector plate 300, and thus has a positive polarity. That is, the cell terminal 400 functions as a positive terminal, which is a first electrode terminal. The battery can 200 is electrically connected to the second electrode plate of the electrode assembly 100 as described above, and thus has a negative polarity.

[0139] The cell terminal 400 may include a terminal insert 410. The terminal insert 410 may be inserted into the battery can 200 through a through hole 211 formed in the closing portion 210 of the battery can 200, and a lower end portion of the terminal insert 410 may be electrically connected to a center portion of the current collector plate 300. The electrical connection may be made through welding. The welding may be laser welding, ultrasonic welding, resistance welding, or the like.

[0140] The terminal insertion portion 410 may penetrate the battery can 200 and the insulator 600 at the same time to be coupled to the current collector plate 300. The lower edge of the terminal insertion portion 410 may be pressed by a caulking tool and riveted toward the inner surface of the upper end of the battery can 200, so that the cell terminal 400 may be firmly fixed in the through hole.

[0141] That is, the lower edge of the terminal insertion portion 410 may be bent toward the inner surface of the battery can 200 by using a crimping tool. As a result, the maximum width of the end of the terminal insertion portion 410 may be wider than the maximum width of the hole in the battery can 200 formed for the terminal insertion portion 410 to penetrate through.

[0142] Referring to FIG. 9 , the riveting structure of the cell terminal 400 may include a cylindrical battery can 200 with one side open, the cell terminal 400 riveted through a through hole 211 formed in the bottom 52 of the battery can 200, and a rivet gasket 54 interposed between the cell terminal 400 and the through hole 211.

[0143] The rivet gasket 54 may be made of insulating and elastic polymer resin. As an example, the rivet gasket 54 may be made of polypropylene, polybutylene terephthalate, polyethylene fluoride, etc., but the present invention is not limited thereto.

[0144] The rivet gasket 54 may include an external gasket 54a interposed between the external flange portion 50b and the outer surface 52a of the bottom 52 of the battery can 200, and an internal gasket 54b interposed between the internal flange portion 50c and the inner surface 52b of the bottom 52 of the battery can 200. Preferably, the external gasket 54a and the internal gasket 54b are separated based on the outer surface 52a of the bottom of the battery can 200.

[0145] Meanwhile, as another example, the terminal insertion part 410 may not be bent toward the inner surface of the battery can 200. For example, referring to FIG 10, the terminal insertion part 410 may have a substantially cylindrical shape penetrating a hole located at substantially the center of the upper surface of the battery can 200.

[0146] In an embodiment of the present invention, the terminal insertion portion 410 may have a circular planar shape, but is not limited thereto. The terminal insertion portion 410 may alternatively have a polygonal shape, a star shape, a shape with legs extending from the center, etc.

[0147] The terminal insert 410 of the cell terminal 400 may pass through a central hole of the insulator 600. The diameter of the central hole of the insulator 600 may be larger than or equal to the diameter of the terminal insert 410. The terminal insert 410 of the cell terminal 400 may pass through the central hole of the insulator 600 and be electrically coupled to the current collector plate 300.

[0148] The insulator 600 is interposed between the battery can 200 and the electrode assembly 100, and in FIG. 3, between the current collector 300 on the upper side of the electrode assembly 100 and the battery can 200. A detailed description of the insulator 600 may be substituted for the description of the insulator 600 of the electrode assembly 100 according to one embodiment of the present invention described above.

[0149] 3, the cap plate 230 is configured to seal the opening 220 of the battery can 200. The cap plate 230 may be made of, for example, a metal material to ensure rigidity.

[0150] The cap plate 230 seals the opening 220 formed at the lower end of the battery can 200. The cap plate 230 may be provided separately from the electrode assembly 100 and without polarity. That is, even if the cap plate 230 is made of a conductive metal material, it does not have polarity. The cap plate 230 without polarity means that the cap plate 230 is electrically insulated from the battery can 200 and the cell terminal 400. In this way, the cap plate 230 does not have to have polarity, and the material thereof does not necessarily have to be a conductive metal.

[0151] The cap plate 230 may be placed and supported on a beading portion 240 formed on the battery can 200. In addition, the cap plate 230 may be fixed by a crimping portion 250. A sealing gasket 260 may be interposed between the cap plate 230 and the crimping portion 250 of the battery can 200 to ensure airtightness of the battery can 200. That is, the sealing gasket 260 may be interposed between the periphery of the cap plate 230 and the opening portion 220 of the battery can 200.

[0152] Meanwhile, the battery can 200 of the present invention may not include at least one of the beading portion 240 and the crimping portion 250. In this case, the sealing gasket 260 may be interposed between a fixing structure provided on the open portion 220 side of the battery can 200 and the cap plate 230 to ensure airtightness of the battery can 200.

[0153] A venting notch 231 may be formed in the cap plate 230 so as to rupture when the internal pressure of the battery can 200 exceeds a critical value.

[0154] For example, the venting notches 231 may be formed on both sides of the cap plate 230 and may be formed in at least one of a continuous circular pattern, a discontinuous circular pattern, and a linear pattern on the surface of the cap plate 230. The venting notches 231 may also be formed in various other patterns.

[0155] The venting notch 231 may be formed at the bottom of the battery can 200 based on the arrangement of the battery can 200, and may be configured such that gas inside the battery can 200 is discharged from the bottom of the battery can 200 when the venting notch 231 is ruptured.

[0156] For example, when the battery can 200 is disposed so that the cell terminal 400 is located at the top as shown in FIG. 3, the venting notch 231 may be formed at the bottom of the battery can 200 with reference to FIG.

[0157] The venting notch 231 may be formed in the cap plate 230 in an area of ​​reduced thickness relative to the surrounding area.

[0158] Because the venting notch 231 is thinner than the surrounding area, it is more likely to break than the surrounding area. If the internal pressure of the battery can 200 increases above a certain level, the venting notch 231 breaks and gas generated inside the battery can 200 is released.

[0159] For example, the venting notch 231 may be formed by partially reducing the thickness of the battery can 200 through notching on one or both sides of the cap plate 230 .

[0160] The cylindrical battery cell 10 according to an embodiment of the present invention has a structure in which both the positive and negative terminals are present at the upper portion, so that the structure of the upper portion is more complicated than that of the lower portion.

[0161] Therefore, in order to smoothly exhaust gas generated inside the battery can 200, a venting notch 231 may be formed in the cap plate 230 constituting the lower surface of the cylindrical battery cell 10.

[0162] In this manner, it is advantageous in terms of user safety if the gas generated inside the battery can 200 provided in the cylindrical battery cell 10 is discharged from the bottom. For example, if the cylindrical battery cell 10 is disposed directly under the driver's seat of an electric vehicle, there is a risk of a safety accident for the driver if the gas is discharged to the top.

[0163] However, when the gas is discharged to the bottom of the battery can 200 as in the cylindrical battery cell 10 according to an embodiment of the present invention, the above-mentioned problem does not occur even if the cylindrical battery cell 10 is placed directly under the driver's seat of an electric vehicle.

[0164] 3, it is preferable that the lower end of the cap plate 230 is disposed higher than the lower end of the battery can 200. In this case, even if the lower end of the battery can 200 contacts the ground or the bottom surface of a housing for configuring a module or pack, the cap plate 230 does not contact the ground or the bottom surface of a housing for configuring a module or pack.

[0165] Therefore, it is possible to prevent a phenomenon in which the pressure required to break the venting notch 231 varies from a designed value depending on the weight of the cylindrical battery cell 10, thereby ensuring smooth breaking of the venting notch 231.

[0166] 3, the lower current collecting plate 700 is coupled to the lower part of the electrode assembly 100. The lower current collecting plate 700 is made of a conductive metal material such as aluminum, steel, copper, nickel, etc., and is electrically connected to the second uncoated portion 120 of the second electrode plate.

[0167] Preferably, the lower current collecting plate 700 is electrically connected to the battery can 200. Therefore, the lower current collecting plate 700 may be fixed by having at least a portion of its edge interposed between the inner surface of the battery can 200 and the sealing gasket 260.

[0168] In one embodiment, at least a portion of the edge of the lower current collecting plate 700 may be fixed to the beading portion 240 by welding while being supported by a lower end surface of the beading portion 240 formed at the lower end of the battery can 200. In a modified embodiment, at least a portion of the edge of the lower current collecting plate 700 may be directly welded to the inner wall surface of the battery can 200.

[0169] Preferably, at least a portion of the lower current collecting plate 700 other than the portion connected to the beading portion may be connected to the bent surface of the second non-coating portion 120 by welding, for example, laser welding.

[0170] Preferably, at least a portion of the edge of the lower current collector 700 may be electrically coupled to one of the upper and lower surfaces of the beading portion 240 adjacent to the crimping portion 250 .

[0171] Meanwhile, the electrode assembly 100 according to an embodiment of the present invention includes a first electrode plate and a second electrode plate, the first electrode plate including a first uncoated portion 110, and the second electrode plate including a second uncoated portion 120. At least a portion of the first uncoated portion 110 and / or the second uncoated portion 120 may be divided into a plurality of segments. The structure of the segments will be described in detail below.

[0172] FIG. 11 is a plan view showing the structure of an electrode plate according to an embodiment of the present invention.

[0173] 11, in the uncoated portion 43 of the electrode plate 60, the heights of the core-side uncoated portion B1 and the outer-periphery-side uncoated portion B3 are equal to or greater than 0 and are relatively lower than the middle uncoated portion B2. The heights of the core-side uncoated portion B1 and the outer-periphery-side uncoated portion B3 may be the same or different.

[0174] Desirably, at least a portion of the intermediate uncoated portion B2 may include a plurality of partial segments 61. The height of the plurality of partial segments 61 may increase stepwise from the core side toward the outer periphery side.

[0175] The segment 61 may be laser notched. The segment 61 may be formed by known metal foil cutting processes such as ultrasonic cutting or punching.

[0176] In FIG. 11, in order to prevent the active material layer 42 and / or the insulating coating layer 44 from being damaged when the uncoated portion 43 is folded, it is preferable to provide a predetermined gap between the lower end of the cutting line (C4 in FIG. 12) between the divided pieces 61 and the active material layer 42. This is because stress is concentrated near the lower end of the cutting line when the uncoated portion 43 is folded. The gap is preferably 0.2 to 4 mm. If the gap is adjusted to the above numerical range, it is possible to prevent the active material layer 42 and / or the insulating coating layer 44 near the lower end of the cutting line from being damaged by stress generated when the uncoated portion 43 is folded. In addition, the gap can prevent damage to the active material layer 42 and / or the insulating coating layer 44 due to tolerance when the divided piece 61 is notched or cut. Preferably, at least a part of the insulating coating layer 44 may be exposed to the outside of the separator when the electrode plate 60 is wound. In this case, when the segment 61 is bent, the insulating coating layer 44 can support the bent point.

[0177] The plurality of segment pieces 61 may be arranged into a plurality of segment piece groups from the core side toward the outer periphery side. At least one of the width, height, and spacing pitch of the segment pieces belonging to the same segment piece group may be substantially the same.

[0178] 12 is a diagram illustrating the definition of the width, height, and spacing pitch of the divided segment 61 according to an embodiment of the present invention. Referring to FIG. 12, the width C1, height C2, and spacing pitch C3 of the divided segment 61 are designed to prevent the uncoated portion 43 from breaking during bending and to improve the welding strength by sufficiently increasing the number of overlapping layers of the uncoated portion 43 and preventing abnormal deformation of the uncoated portion 43. Abnormal deformation refers to the uncoated portion below the bending point collapsing and deforming irregularly without maintaining a straight state.

[0179] Preferably, the width C1 of the divided piece 61 can be adjusted in the range of 1 mm to 8 mm. If C1 is less than 1 mm, when the divided piece 61 is bent toward the core, there will be an area where the overlap is not sufficient to ensure sufficient welding strength, or there will be an empty space (gap). On the other hand, if C1 exceeds 8 mm, there is a risk that the uncoated portion 43 near the bending point will break due to stress when the divided piece 61 is bent.

[0180] Also, the height of the divided pieces 61 can be adjusted in the range of 2 mm to 10 mm. If C2 is less than 2 mm, when the divided pieces 61 are bent toward the core, there is a region where the divided pieces 61 do not overlap to an extent that the welding strength can be sufficiently ensured, or there is an empty space (gap). On the other hand, if C2 exceeds 10 mm, it is difficult to manufacture an electrode plate while uniformly maintaining the flatness of the non-coated portion in the winding direction X. That is, the non-coated portion becomes high and swells are generated. Also, the separation pitch C3 of the divided pieces 61 can be adjusted in the range of 0.05 mm to 1 mm. If C3 is less than 0.05 mm, there is a risk that the non-coated portion 43 near the bending point will be torn due to stress when the divided pieces 61 are bent. On the other hand, if C3 exceeds 1 mm, there is a risk that the divided pieces 61 do not overlap to an extent that the welding strength can be sufficiently ensured, or there is an empty space (gap) when the divided pieces 61 are bent.

[0181] 12, a cut portion 62 is interposed between adjacent segments 61 in the winding direction X. The cut portion 62 corresponds to a space created when the uncoated portion 43 is removed. Desirably, the corners of the lower end of the cut portion 62 may be rounded (see partial enlargement). The rounded shape can relieve stress applied to the lower end of the cut portion 62 when the electrode plate 60 is wound and / or the segments 61 are bent.

[0182] Referring further to FIG. 11, the width d of the core-side uncoated portion B1 B1 is designed so that the cavity of the core of the electrode assembly is not blocked when the divided piece 61 of the intermediate uncoated portion B2 is bent toward the core.

[0183] As an example, the width d of the core-side uncoated portion B1 B1 may increase in proportion to the bending length of the divided segment 61 of group 1. The bending length corresponds to the height of the divided segment 61 based on the bending point (63 in FIG. 12). Referring to FIG. 12, C4 indicates the lowest point at which bending is possible. The bending point may be appropriately set at the position indicated by C4 or above C4. The bending length is the length from the bending point to the upper end of the divided segment 61. Specifically, the bending point may be set at a predetermined point of the height C2 of the divided segment 61 based on C4. The predetermined point may be set to prevent physical damage to the active material layer 42 or the insulating coating layer 44 due to stress generated when the divided segment 61 is bent, and to ensure sufficient welding strength when a current collector plate is welded to the bending region of the divided segment 61 by ensuring a sufficient number of layers overlapping in the radial direction when the divided segment 61 is bent in the radial direction of the electrode assembly.

[0184] In a specific example, when the electrode plate 60 is used to manufacture an electrode assembly for a cylindrical cell of form factor 46800, the width d of the core-side blank portion B1 is B1 can be set to 180 mm to 350 mm depending on the diameter of the core of the electrode assembly.

[0185] In one example, the width of each segment group can be designed to accommodate the same winding turn of the electrode assembly.

[0186] Here, the winding turns can be counted based on the end of the core-side uncoated portion B1 when the electrode plate 60 is in a wound state.

[0187] In another example, the width of each segment group can be designed to comprise at least one winding turn of the electrode assembly.

[0188] In yet another example, the width and / or height and / or spacing pitch of the segments 61 belonging to the same segment group may increase or decrease gradually and / or stepwise and / or irregularly within the group.

[0189] Group 1 to Group 8 are merely examples of the segment groups. The number of groups, the number of segment pieces 61 included in each group, and the width of the group can be suitably adjusted so that the segment pieces 61 are overlapped in multiple layers to maximize stress dispersion during the bending process of the plain portion 43 and ensure sufficient welding strength.

[0190] In another example, the height of the outer peripheral uncoated portion B3 may decrease gradually or in steps.

[0191] In yet another example, the division structure of the middle plain portion B2 can extend to the outer plain portion B3 (see dotted line). In this case, the outer plain portion B3 can also include multiple division segments, similar to the middle plain portion B2. In this case, the division segments of the outer plain portion B3 can have a width and / or height and / or spacing pitch greater than those of the middle plain portion B2. Alternatively, the division structure of the outer plain portion B3 can be substantially identical to the group of division segments located at the outermost side of the middle plain portion B2.

[0192] In a specific embodiment, when the electrode plate 60 is used to manufacture an electrode assembly of a cylindrical cell of form factor 46800, the width d of the core-side uncoated portion B1 is B1The width of group 1 may be 35% to 40% of the width of core-side plain portion B1. The width of group 2 may be 130% to 150% of the width of group 1. The width of group 3 may be 120% to 135% of the width of group 2. The width of group 4 may be 85% to 90% of the width of group 3. The width of group 5 may be 120% to 130% of the width of group 4. The width of group 6 may be 100% to 120% of the width of group 5. The width of group 7 may be 90% to 120% of the width of group 6. The width of group 8 may be 115% to 130% of the width of group 7. The width d of outer periphery-side plain portion B3 B3 The width of the core-side uncoated portion B1 may be 180 mm to 350 mm, similar to the width of the core-side uncoated portion B1.

[0193] The reason why the widths of groups 1 to 8 do not show a constant increase or decrease pattern is that although the widths of the sub-segments gradually increase from group 1 to group 8, the number of sub-segments included in a group is limited to an integer. Therefore, the number of sub-segments may decrease in a particular sub-segment group. Therefore, the widths of the groups may show an irregular change from the core side to the outer periphery side, as shown in the above example.

[0194] That is, when the winding direction widths for three consecutively adjacent segment groups in the circumferential direction of the electrode assembly are W1, W2, and W3, respectively, the combination of segment groups may include one in which W3 / W2 is smaller than W2 / W1.

[0195] In the specific example described above, this applies to groups 4 to 6. The width ratio of group 5 to group 4 is 120% to 130%, and the width ratio of group 6 to group 5 is 100% to 120%, which is smaller than 120% to 130%.

[0196] FIG. 13 is a plan view showing the structure of an electrode plate according to another embodiment of the present invention, and FIG. 14 is a diagram showing the definitions of the width, height and spacing pitch of the segments of FIG.

[0197] 13, the electrode plate 70 is substantially the same in configuration as that of FIG. 11 except that the shape of the segment 61' is changed from a square to a trapezoid.

[0198] FIG. 14 is a diagram showing the definitions of the width, height and separation pitch of a trapezoidal segment 61'.

[0199] Referring to FIG. 14, the width D1, height D2 and spacing pitch D3 of the divided piece 61' are designed to prevent tearing of the uncoated portion 43 near the bending point when the uncoated portion 43 is bent and to ensure sufficient weld strength by sufficiently increasing the number of overlapping layers of the uncoated portion 43 while preventing abnormal deformation of the uncoated portion 43.

[0200] Preferably, the width D1 of the divided piece 61' may be adjusted in the range of 1 mm to 8 mm. If D1 is less than 1 mm, when the divided piece 61' is bent toward the core side, there is a risk of an area where the divided piece 61' does not overlap to an extent that the welding strength can be sufficiently ensured or an empty space (gap) may be generated. On the other hand, if D1 exceeds 8 mm, there is a risk of the uncoated portion 43 near the bending point being broken by stress when the divided piece 61 is bent. In addition, the height of the divided piece 61' may be adjusted in the range of 2 mm to 10 mm. If D2 is less than 2 mm, there is a risk of an area where the divided piece 61' does not overlap to an extent that the welding strength can be sufficiently ensured or an empty space (gap) may be generated when the divided piece 61' is bent toward the core side. On the other hand, if D2 exceeds 10 mm, it is difficult to manufacture an electrode plate while maintaining the flatness of the uncoated portion 43 in the winding direction uniformly. Furthermore, the separation pitch D3 of the divided segments 61' can be adjusted within a range of 0.05 mm to 1 mm. If D3 is less than 0.05 mm, the uncoated portion 43 near the bending point D4 may be torn due to stress when the divided segments 61' are bent. On the other hand, if D3 exceeds 1 mm, there is a risk that an area where the divided segments 61' do not overlap enough to ensure sufficient welding strength or an empty space (gap) may be generated when the divided segments 61' are bent.

[0201] A cut portion 62 is interposed between adjacent divided pieces 61' in the winding direction X. The cut portion 62 corresponds to a space created when the plain portion 43 is removed. Desirably, the corner portion of the lower end of the cut portion 62 may be rounded (see partial enlargement). The rounded shape can relieve stress when the divided pieces 61' are bent.

[0202] 13 and 14, the lower interior angle θ of the trapezoid of the plurality of segment pieces 61' may gradually increase from the core side toward the outer periphery. As the radius of the electrode assembly increases, the curvature increases. If the lower interior angle θ of the segment piece 61' increases with the increase in the radius of the electrode assembly, the stress generated in the radial and circumferential directions when the segment piece 61' is bent can be alleviated. In addition, as the lower interior angle θ increases, the overlapping area and the number of overlapping layers with the inner segment piece 61' when the segment piece 61' is bent also increase, so that uniform welding strength can be secured in the radial and circumferential directions and the bent surface can be formed flat.

[0203] In one example, when electrode plate 70 is used to manufacture an electrode assembly for a cylindrical cell of form factor 46800, the inner angle of segment 61' may increase stepwise in the range of 60° to 85° as the core (cavity) diameter is 4 mm and the radius of the electrode assembly increases from 4 mm to 22 mm.

[0204] In a modified embodiment, the height of the outer plain portion B3 may decrease gradually or stepwise, as in the above-described embodiment. Also, the division structure of the middle plain portion B2 may extend to the outer plain portion B3 (see dotted line). In this case, the outer plain portion B3 may also include a plurality of division segments, similar to the middle plain portion B2. In this case, the division segments of the outer plain portion B3 may have a width and / or height and / or spacing pitch greater than those of the middle plain portion B2. Alternatively, the division structure of the outer plain portion B3 may be substantially the same as the group of division segments located at the outermost side of the middle plain portion B2.

[0205] In a specific embodiment, when the electrode plate 70 is used to manufacture an electrode assembly of a cylindrical cell having a form factor of 46800, the width d of the core-side uncoated portion B1 is B1 The width of group 1 may be 35% to 40% of the width of core-side plain portion B1. The width of group 2 may be 130% to 150% of the width of group 1. The width of group 3 may be 120% to 135% of the width of group 2. The width of group 4 may be 85% to 90% of the width of group 3. The width of group 5 may be 120% to 130% of the width of group 4. The width of group 6 may be 100% to 120% of the width of group 5. The width of group 7 may be 90% to 120% of the width of group 6. The width of group 8 may be 115% to 130% of the width of group 7. The width d of outer periphery-side plain portion B3 B3 The width of the core-side uncoated portion B1 may be 180 mm to 350 mm, similar to the width of the core-side uncoated portion B1.

[0206] The reason why the widths of groups 1 to 8 do not show a constant increase or decrease pattern is that although the widths of the sub-segments gradually increase from group 1 to group 8, the number of sub-segments included in a group is limited to an integer. Therefore, the number of sub-segments may decrease in a particular sub-segment group. Therefore, the widths of the groups may show an irregular change from the core side to the outer periphery side, as shown in the above example.

[0207] That is, when the winding direction widths for three consecutively adjacent segment groups in the circumferential direction of the electrode assembly are W1, W2, and W3, respectively, the combination of segment groups may include one in which W3 / W2 is smaller than W2 / W1.

[0208] In the specific example described above, this applies to groups 4 to 6. The width ratio of group 5 to group 4 is 120% to 130%, and the width ratio of group 6 to group 5 is 100% to 120%, which is smaller than 120% to 130%.

[0209] FIG. 15 is a cross-sectional view of an electrode assembly according to an embodiment of the present invention taken along the Y-axis (winding axis) direction.

[0210] Referring to Figure 15, the uncoated portion 43a of the electrode plate includes a core-side uncoated portion B1 adjacent to the core of the electrode assembly 100, an outer-periphery-side uncoated portion B3 adjacent to the outer peripheral surface of the electrode assembly 100, and an intermediate uncoated portion B2 interposed between the core-side uncoated portion B1 and the outer-periphery-side uncoated portion B3.

[0211] The height of core-side uncoated portion B1 is relatively lower than the height of intermediate uncoated portion B2. The folding length of the innermost uncoated portion 43a in intermediate uncoated portion B2 is equal to or shorter than the radial length R of core-side uncoated portion B1. The folding length H corresponds to the height of uncoated portion 43a based on the point where uncoated portion 43a is folded (h in Fig. 12, h in Fig. 14).

[0212] Therefore, even if the middle plain portion B2 is folded, the folded portion does not block the cavity 102 in the core of the electrode assembly 100. If the cavity 102 is not blocked, the electrolyte injection process is not hindered, and the efficiency of the electrolyte injection is improved. In addition, a welding jig can be inserted through the cavity 102 to easily perform the welding process between the current collector plate on the negative electrode (or positive electrode) side and the battery can (or rivet terminal).

[0213] The height of the outer plain portion B3 is relatively lower than the height of the intermediate plain portion B2, which prevents the beading portion of the battery can from coming into contact with the outer plain portion B3 when the beading portion is pressed against the outer plain portion B3.

[0214] In one variation, the height of outer periphery plain area B3 may decrease gradually or in steps, unlike Fig. 15. Also, in Fig. 15, the height of intermediate plain area B2 is uniform over a portion of the outer periphery, but the height of intermediate plain area B2 may increase gradually or in steps from the boundary between core-side plain area B1 and intermediate plain area B2 to the boundary between intermediate plain area B2 and outer periphery plain area B3.

[0215] The lower uncoated portion 43b has the same structure as the upper uncoated portion 43a. In one variation, the lower uncoated portion 43b may have the structure of a conventional electrode plate or the structure of an electrode plate in another embodiment (variation).

[0216] Ends 101 of the upper uncoated portion 43a and the lower uncoated portion 43b may be bent from the outer periphery side to the core side of the electrode assembly 100. At this time, the core-side uncoated portion B1 and the outer periphery-side uncoated portion B3 are not substantially bent.

[0217] When the middle plain portion B2 includes a plurality of segments, bending stress is alleviated, thereby preventing the plain portion 43a near the bending point from being torn or abnormally deformed. In addition, when the width and / or height and / or spacing pitch of the segments are adjusted within the numerical range of the above-mentioned embodiment, the segments are overlapped to an extent that sufficient welding strength can be ensured as they are bent toward the core, and no open space (gap) is formed on the bending surface (surface viewed from the Y-axis direction).

[0218] FIG. 16 is a cross-sectional view of an electrode assembly according to another embodiment of the present invention taken along the Y-axis (winding axis) direction.

[0219] 16, the electrode assembly 110 has substantially the same configuration as the electrode assembly 100 in FIG 15, except that the height of the outer peripheral uncoated portion B3 is substantially the same as the height of the outermost portion of the intermediate uncoated portion B2. The outer peripheral uncoated portion B3 may include a plurality of segments.

[0220] In the electrode assembly 110, the height of the core-side uncoated area B1 is relatively lower than the height of the middle uncoated area B2. In addition, the bent length H of the innermost uncoated area in the middle uncoated area B2 is equal to or shorter than the radial length R of the core-side uncoated area B1.

[0221] Therefore, even if the middle plain portion B2 is folded, the folded portion does not block the cavity 112 of the core of the electrode assembly 110. If the cavity 112 is not blocked, the electrolyte injection process is not hindered, and the efficiency of the electrolyte injection is improved. Also, a welding jig can be inserted through the cavity 112 to easily perform the welding process between the current collector plate on the negative electrode (or positive electrode) side and the battery can (or rivet terminal).

[0222] In one modified example, the structure in which the height of the intermediate uncoated portion B2 increases gradually or in steps from the core side to the outer periphery side may be extended to the outer periphery uncoated portion B3. In this case, the height of the uncoated portion 43a may increase gradually or in steps from the boundary between the core side uncoated portion B1 and the intermediate uncoated portion B2 to the outermost surface of the electrode assembly 110.

[0223] The lower uncoated portion 43b has the same structure as the upper uncoated portion 43a. In one variation, the lower uncoated portion 43b may have the structure of a conventional electrode plate or the structure of an electrode plate in another embodiment (variation).

[0224] Ends 111 of the upper uncoated portion 43a and the lower uncoated portion 43b may be bent from the outer periphery side to the core side of the electrode assembly 110. At this time, the core-side uncoated portion B1 is not substantially bent.

[0225] When the middle uncoated portion B2 and the outer peripheral uncoated portion B3 include a plurality of segments, bending stress is alleviated, thereby preventing the uncoated portions 43a, 43b near the bending points from being torn or abnormally deformed. In addition, when the width and / or height and / or spacing pitch of the segments are adjusted within the numerical range of the above-mentioned embodiment, the segments overlap each other while being bent toward the core to an extent that sufficient welding strength can be ensured, and no open space (gap) is formed on the bending surface (surface viewed from the Y-axis direction).

[0226] FIG. 17 is a diagram illustrating a schematic configuration of a battery pack according to an embodiment of the present invention.

[0227] 17, a battery pack 800 according to an embodiment of the present invention includes an assembly of electrically connected cylindrical battery cells 10, and a pack housing 810 that accommodates the assembly. The cylindrical battery cells 10 are the battery cells according to the above-described embodiment. For convenience of illustration, components such as bus bars for electrical connection of the cylindrical battery cells 10, a cooling unit, and external terminals are not shown.

[0228] The battery pack 800 is mounted on an automobile 900. The automobile 900 may be, for example, an electric automobile, a hybrid automobile, or a plug-in hybrid automobile. The automobile 900 includes a four-wheeled automobile or a two-wheeled automobile.

[0229] FIG. 18 is a diagram for explaining an automobile including the battery pack of FIG.

[0230] 18, an automobile 900 according to an embodiment of the present invention includes a battery pack 800 according to an embodiment of the present invention. The automobile 900 operates by receiving a supply of power from the battery pack 800 according to an embodiment of the present invention.

[0231] 19 to 25 are diagrams illustrating a process of a method for manufacturing a cylindrical battery cell according to an embodiment of the present invention.

[0232] A method for manufacturing a cylindrical battery cell according to an embodiment of the present invention will now be described, with the above description being substituted for content common to the cylindrical battery cell according to the above-described embodiment of the present invention.

[0233] First, an electrode assembly 100 is prepared as shown in Fig. 19. The electrode assembly 100 is a jelly-roll type electrode assembly having a structure in which a sheet-like first electrode plate 140 and a second electrode plate 160 and a separator 150 interposed therebetween are wound in one direction. The first electrode plate 140 includes a first uncoated portion 110 on which an active material layer is not coated at a long side end, and the first uncoated portion 110 and the second uncoated portion 120 are exposed to the outside of the separator while forming a plurality of winding turns based on the center of the electrode assembly 100, and are themselves used as electrode tabs.

[0234] Next, the current collector plate 300 is coupled to the first uncoated portion 110 of the electrode assembly 100 .

[0235] Thereafter, as shown in FIG. 20, a battery can 200 is prepared, which has an open portion 220 in which the electrode assembly 100 is housed and a partially closed portion 210 on the opposite side thereof and is electrically connected to the second electrode plate 160.

[0236] Next, the cell terminal 400 is connected to the battery can 200 by riveting through the through hole 211 in the closure portion 210 of the battery can 200 .

[0237] 21, the battery can 200 is arranged so that the cell terminal 400 is located at the bottom, and the insulator 600 is coupled to the inner surface of the closing part 210 of the battery can 200. In one embodiment, at least one protrusion 610 is formed on the outer circumferential surface of the insulator 600, and the insulator 600 may be coupled to the battery can 200 through interference fit. Preferably, a plurality of protrusions 610 are provided, and the plurality of protrusions 610 may be formed at predetermined intervals on the outer circumferential surface of the insulator 600 and may be crimped through interference fit. In another embodiment, a heat fusion layer is formed on a surface of the insulator 600 facing the inner surface of the closing part 210 of the battery can 200, and the insulator 600 may be fixed to the battery can 200 by heat fusion. In still another embodiment, an adhesive layer is formed on an upper surface of the insulator 600 that contacts the battery can 200, and the insulator 600 may be fixed to the battery can 200 by adhesion. In yet another embodiment, the insulator 600 may be secured to the battery can 200 by double-sided tape.

[0238] Preferably, the electrolyte may be injected in a state where the battery can 200 is upright so that the cell terminal 400 faces the direction of gravity. At least one through hole 620 may be provided on an upper surface of the insulator 600 connected to the outer circumferential surface of the insulator 600, and the electrolyte may move into the electrode assembly 100 through the through hole 620. Preferably, a plurality of through holes 620 may be formed, and the plurality of through holes 620 may be spaced apart at a predetermined interval. Preferably, a plurality of through holes 620 may be arranged on a straight line extending from the center of the insulator 600 toward the outer circumferential surface of the insulator 600. Preferably, a plurality of through holes 620 may be arranged on each of a plurality of straight lines radially extending from the center of the insulator 600 toward the outer circumferential surface of the insulator 600.

[0239] Thereafter, as shown in FIG. 22, the electrode assembly 100 is inserted into the battery can 200, and the insulator 600 is interposed between the battery can 200 and the current collector plate 300.

[0240] 23, the lower current collecting plate 700 is joined to the second uncoated portion 120 of the second electrode plate 160 by welding. Depending on the process design, the welding of the lower current collecting plate 700 may be performed before the electrode assembly 100 is inserted into the battery can 200. The detailed description of the second electrode plate 160 and the lower current collecting plate 700 is substituted for the description above.

[0241] 24, the beading portion 240 is formed on the battery can 200. The edge of the lower current collecting plate 700 is welded while being placed on a flat surface adjacent to the crimping portion 250 of the beading portion 240. The detailed description of the beading portion 240 is as described above.

[0242] 25, the crimping part 250 is formed on the battery can 200. When the crimping part 250 is formed, the periphery of the cap plate 230 is supported on the beading part 240 with the sealing gasket 260 interposed therebetween, and the crimping part 250 presses the sealing gasket 260 while the upper end of the battery can 200 is bent inward to fix the cap plate 230. The detailed description of the crimping part 250 is as described above.

[0243] According to the above-described manufacturing method, since the insulator is fixed to the battery can and does not move, when the jelly-roll type electrode assembly is subsequently inserted into the battery can, the insulator can be coupled to the jelly-roll type electrode assembly at an accurate position, thereby improving insulation and preventing defects.

[0244] As described above, the present invention has been described using limited embodiments and drawings. However, the present invention is not limited thereto, and it goes without saying that various modifications and variations can be made by a person having ordinary knowledge in the technical field to which the present invention belongs within the technical spirit of the present invention and the equivalent scope of the claims. [Industrial Applicability]

[0245] INDUSTRIAL APPLICABILITY The present invention relates to a cylindrical battery cell, a battery pack and an automobile including the same, and a manufacturing method for a cylindrical battery cell, and is particularly applicable to the secondary battery-related industry. [Explanation of symbols]

[0246] 10 Cylindrical Battery Cells 21 Beading Section 42 Active material layer 43 Plain section 44 Insulating coating layer 52 Bottom 52 External surface 52 Inner surface 54 Rivet gasket 60 Electrode plate 61 min section 62 Cut section 70 Electrode plate 100 electrode assembly 101 End 102 Cavity 110 Electrode assembly 110 First Plain Section 111 End 112 Cavity 120 Second Plain Section 140 1st electrode plate 150 Separation membrane 160 2nd electrode plate 200 Battery Can 210 Closing part 211 Through hole 220 Open area 230 Cap Plate 231 Venting Notch 240 Beading section 250 Crimping section 260 Sealing Gasket 300 Current collector 400 Cell Terminal 410 Terminal insertion part 500 Electrical Tape 600 Insulator 610 Protrusion 620 Through hole 700 Lower current collector 800 Battery Pack 810 Pack Housing 900 Automobiles

Claims

1. a jelly-roll type electrode assembly having a structure in which a sheet-shaped first electrode plate, a sheet-shaped second electrode plate, and a separator interposed between the first electrode plate and the second electrode plate are wound in one direction; a battery can having an open portion in which the electrode assembly is housed and a partially closed portion opposite the open portion, the battery can being electrically connected to the second electrode plate; a current collector plate electrically connected to the first electrode plate; a cell terminal connected to the current collector through a through hole of the closing portion of the battery can; an insulator fixed to the battery can and interposed between the battery can and the current collector plate; Including, At least one protrusion is provided on an outer circumferential surface of the insulator so that the insulator is coupled to the battery can through an interference fit when the electrode assembly is housed in the battery can.

2. 2. The cylindrical battery cell of claim 1, wherein the first electrode plate of the electrode assembly includes a first uncoated portion at a long side end portion where an active material layer is not coated, the first uncoated portion forming a plurality of winding turns based on a center of the electrode assembly, being exposed to an outside of the separator, and being used as an electrode tab and electrically connected to the current collector plate.

3. 10. The cylindrical battery cell according to claim 1, wherein the insulator has a shape corresponding to a cross-sectional shape of the jelly-roll-type electrode assembly.

4. The protrusions are provided in a plurality, The cylindrical battery cell according to claim 1 , wherein the plurality of protrusions are provided at predetermined intervals on the outer circumferential surface of the insulator.

5. The cylindrical battery cell according to claim 4 , wherein the protrusions are equally spaced apart on the outer circumferential surface of the insulator.

6. 2. The cylindrical battery cell according to claim 1, wherein a heat sealing layer is formed on a surface of the insulator facing an inner surface of the closing portion of the battery can such that the insulator is fixed to the battery can by heat sealing when the electrode assembly is housed in the battery can.

7. 2. The cylindrical battery cell according to claim 1, wherein an adhesive layer is formed on an upper surface of the insulator in contact with the battery can such that the insulator is fixed to the battery can by adhesion when the electrode assembly is housed in the battery can.

8. 10. The cylindrical battery cell according to claim 1, wherein the insulator is fixed to the battery can by double-sided tape.

9. The cylindrical battery cell according to claim 1 , wherein at least one through-hole through which an electrolyte can move is formed on an upper surface of the insulator connected to an outer circumferential surface of the insulator.

10. The through holes are formed in a plurality of pieces, 10. The cylindrical battery cell according to claim 9, wherein the plurality of through-holes are spaced apart at a preset interval.

11. The cylindrical battery cell according to claim 10 , wherein a plurality of through holes are arranged on a straight line from a center of the insulator toward an outer circumferential surface of the insulator.

12. 11. The cylindrical battery cell according to claim 10, wherein a plurality of through holes are arranged on each of a plurality of straight lines radially arranged from a center of the insulator toward an outer circumferential surface of the insulator.

13. The cylindrical battery cell according to claim 10 , wherein an arrangement interval between the plurality of through holes increases or decreases along a radial direction.

14. 10. The cylindrical battery cell according to claim 9, wherein the through hole has a diameter of 1.0 mm to 3.0 mm.

15. The cylindrical battery cell according to claim 1 , wherein a distance from a center of the insulator to an end of the protrusion is greater than a radius of the electrode assembly.

16. 2. The cylindrical battery cell according to claim 1, wherein a distance from a center of the insulator to an end of the protrusion is greater than an inner diameter of the battery can.

17. 10. The cylindrical battery cell of claim 1, wherein a periphery of the insulator has a cross-sectional shape that corresponds to a cross-sectional shape of an edge of a closure of the battery can.

18. 2. The cylindrical battery cell according to claim 1, wherein a thickness of the insulator corresponds to a distance between an inner surface of the closure of the battery can and the current collector plate.

19. 20. The cylindrical battery cell of claim 18, wherein the insulator has a thickness of 0.8 mm or more and 1.6 mm or less.

20. an upper portion of the insulator contacts an inner surface of the closure of the battery can; 2. The cylindrical battery cell according to claim 1, wherein a lower portion of the insulator contacts an upper surface of the current collector plate.

21. 10. The cylindrical battery cell of claim 1, wherein the insulator comprises an insulating polymer material.

22. 22. The cylindrical battery cell of claim 21, wherein the insulator is made of polyethylene terephthalate, polybutylene terephthalate, or polypropylene, or is made of polyethylene terephthalate, polybutylene terephthalate, or polypropylene with at least one of a heat-resistant additive and a flame retardant.

23. The cylindrical battery cell according to claim 1 , wherein the insulator is made of a resilient material.

24. 2. The cylindrical battery cell according to claim 1, wherein the insulator has a central hole having a preset diameter at a center portion thereof, and a lower portion of the cell terminal is exposed from the central hole.

25. The cylindrical battery cell according to claim 1 , wherein an insulating tape is attached to an outer peripheral surface of the electrode assembly at least up to a point corresponding to a periphery of the insulator.

26. The cylindrical battery cell according to claim 2 , wherein at least a portion of the first uncoated portion is divided into a plurality of segments along a winding direction of the electrode assembly.

27. The cylindrical battery cell according to claim 26 , wherein the plurality of segments are folded along a radial direction of the electrode assembly.

28. The cylindrical battery cell according to claim 26 , wherein the plurality of segments are overlapped in multiple layers along a radial direction of the electrode assembly.

29. 10. The cylindrical battery cell of claim 1, further comprising a cap plate configured to seal the open portion of the battery can.

30. a sealing gasket interposed between a periphery of the cap plate and the opening of the battery can, the battery can includes a beading portion pressed into the inside of the battery can in an area adjacent to the opening, 30. The cylindrical battery cell of claim 29, wherein the battery can includes a crimping portion that extends toward the inside of the battery can and is bent to enclose and fix a periphery of the cap plate together with the sealing gasket.

31. The cylindrical battery cell according to claim 30 , wherein the crimping portion is formed at a lower portion of the battery can based on an arrangement state of the battery can.

32. 30. The cylindrical battery cell of claim 29, wherein the cap plate includes a venting notch that ruptures when an internal pressure of the battery can exceeds a critical value.

33. 33. The cylindrical battery cell of claim 32, wherein the venting notches are formed on both sides of the cap plate and are formed in at least one of a continuous circular pattern, a discontinuous circular pattern, and a linear pattern on a surface of the cap plate.

34. 33. The cylindrical battery cell of claim 32, wherein the venting notch is formed at a lower portion of the battery can based on an arrangement state of the battery can, and when the venting notch is ruptured, gas inside the battery can is discharged from a lower side of the battery can.

35. 26. The cylindrical battery cell according to claim 25, wherein the width of the bent portion of the insulating tape is 3 mm to 10 mm.

36. 26. The cylindrical battery cell according to claim 25, wherein the insulating tape comprises a polyimide-based resin layer.

37. 37. A battery pack comprising at least one cylindrical battery cell according to any one of claims 1 to 36.

38. 38. A motor vehicle comprising at least one battery pack according to claim 37.

39. (a) preparing a jelly-roll type electrode assembly having a structure in which a sheet-shaped first electrode plate, a sheet-shaped second electrode plate, and a separator interposed between the first electrode plate and the second electrode plate are wound in one direction; (b) coupling a current collector to a first uncoated portion of the electrode assembly; (c) preparing a battery can having an open portion in which the electrode assembly is housed and a partially closed portion opposite the open portion, the battery can being electrically connected to the second electrode plate; (d) connecting a cell terminal through a through hole of the closure of the battery can; (e) bonding an insulator to an inner surface of the closure of the battery can; (f) inserting the electrode assembly into the battery can and interposing the insulator between the battery can and the current collector; Including, At least one protrusion is provided on an outer circumferential surface of the insulator, and step (e) includes coupling the insulator to the battery can through an interference fit.

40. 40. The method of claim 39, wherein step (a) comprises a step in which the first electrode plate of the electrode assembly includes a first uncoated portion at a long side end portion where an active material layer is not coated, the first uncoated portion forming a plurality of winding turns based on a center of the electrode assembly, being exposed to the outside of the separator, and being used as an electrode tab itself to be electrically connected to the current collector plate.

41. The protrusions are provided in a plurality of pieces, and the protrusions are provided at predetermined intervals on the outer circumferential surface of the insulator, The method for manufacturing a cylindrical battery cell according to claim 39 , wherein in step (e), the protrusions are crimped through an interference fit.

42. 40. The method for manufacturing a cylindrical battery cell according to claim 39, wherein the insulator has a heat sealing layer on a surface facing the inner surface of the closure of the battery can, and step (e) includes a step of fixing the insulator to the battery can by heat sealing.

43. 40. The method of claim 39, wherein an adhesive layer is provided on an upper surface of the insulator that contacts the battery can, and step (e) includes a step of fixing the insulator to the battery can by adhesion.

44. 40. The method of claim 39, wherein step (e) comprises fixing the insulator to the battery can by double-sided tape.

45. 45. The method for manufacturing a cylindrical battery cell according to any one of claims 39 to 44, further comprising: (g) injecting an electrolyte while the battery can is upright so that the cell terminal faces a gravity direction.

46. At least one through hole is provided on an upper surface of the insulator connected to an outer circumferential surface of the insulator, The method for manufacturing a cylindrical battery cell according to claim 45, wherein in step (g), the electrolyte moves into the inside of the electrode assembly through the through-holes.

47. The method for manufacturing a cylindrical battery cell according to claim 46, wherein a plurality of the through holes are formed, and the plurality of the through holes are spaced apart at a predetermined interval.

48. The method for manufacturing a cylindrical battery cell according to claim 47 , wherein a plurality of through holes are arranged on a straight line from a center of the insulator toward an outer circumferential surface of the insulator.

49. The method for manufacturing a cylindrical battery cell according to claim 47 , wherein a plurality of through holes are arranged for each of a plurality of straight lines radially arranged from a center of the insulator toward an outer circumferential surface of the insulator.

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