Cylindrical battery cell, battery pack including the same, and motor vehicle

Abstract

The present invention discloses a battery cell, a battery pack including the same, and a motor vehicle. The present invention includes an electrode assembly having a structure in which a first electrode plate, a second electrode plate, and a separator interposed therebetween are wound in one direction, a battery can provided on one side so as to house the electrode assembly and having an open portion and a partial closing portion provided on the opposite side thereof, a battery can electrically connected to the second electrode plate, a current collector electrically connected to the first electrode plate, a cell terminal connected to the current collector through a through hole in the closing portion of the battery can, an insulator provided with a center hole configured to expose the lower portion of the cell terminal and interposed between the battery can and the current collector.

Description

Technical Field

[0001] The present invention relates to an electrode assembly, a cylindrical battery cell, and a battery pack including the same.

[0002] This application claims priority based on Korean Patent Application No. 10-2022-0087508 filed on July 15, 2022, and all of the contents disclosed in the specification and drawings of the application are incorporated into this application.

Background Art

[0003] Secondary batteries with high applicability according to product groups and having electrical characteristics such as high energy density are widely applied not only to portable devices but also to electric vehicles (EVs) or hybrid electric vehicles (HEVs) driven by an electric drive source.

[0004] Such secondary batteries are attracting attention as a new energy source for improving energy efficiency because they are environmentally friendly not only in that they can significantly reduce the use of fossil fuels but also in that they do not produce any by-products associated with energy use.

[0005] Currently, widely used types of secondary batteries include lithium-ion batteries, lithium polymer batteries, nickel cadmium batteries, nickel metal hydride batteries, nickel zinc batteries, etc. The operating voltage of such a single secondary battery cell is about 2.5V to 4.5V.

[0006] Therefore, when a higher output voltage is required, a plurality of battery cells are connected in series to form a battery pack. Also, a battery pack can be configured by connecting a plurality of battery cells in parallel according to the charge and discharge capacity required for the battery pack. Therefore, the number of battery cells included in the battery pack can be variously set according to the required output voltage or charge and discharge capacity.

[0007] On the one hand, as types of secondary battery cells, cylindrical, prismatic, and pouch-type battery cells are known. In the case of a cylindrical battery cell, a separator, which is an insulator, is interposed between the positive electrode and the negative electrode, and it is wound up to form a jelly-roll-shaped electrode assembly, which is inserted into the inside of a battery can together with an electrolyte to constitute a battery.

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

[0009] On the other hand, recently, as cylindrical battery cells are applied to electric vehicles, the form factor of cylindrical battery cells has been increasing. That is, the diameter and height of the cylindrical battery cell are increasing compared to cylindrical battery cells having conventional form factors such as 18650 and 21700. The increase in the form factor brings about an increase in energy density, an increase in safety against thermal runaway, and an improvement in cooling efficiency. And in the case of a cylindrical battery cell with an increased form factor, the importance of insulation between the battery can and the jelly-roll-shaped electrode assembly is further increasing.

[0010] The insulator inserted into the cylindrical battery cell for insulation is usually manufactured in a sheet shape. However, when the sheet-shaped insulator is inserted into the battery can in a state of being placed on the jelly-roll-shaped electrode assembly, the insulator may move. As a result, since the insulator detaches from the accurate position, the insulation property may decrease and defects may occur. Summary of the Invention Problems to be Solved by the Invention

[0011] The present invention has been made in view of the above problems. Since the insulator is fixed to the battery can and does not move, when the subsequent jelly roll type electrode assembly is 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 the occurrence of defects. An object of the present invention is to provide an electrode assembly, a cylindrical battery cell, a battery pack including the same, and an automobile.

[0012] Another object of the present invention is to prevent damage to the electrode assembly by causing the insulator to descend at an appropriate speed due to natural deformation of the protrusion when the jelly roll type electrode assembly is inserted into the battery can in a free fall manner.

[0013] Still another object of the present invention is to provide a battery pack manufactured using a cylindrical battery cell having an improved structure and an automobile including the same.

[0014] However, the technical problems to be solved by the present invention are not limited to the above problems, and other problems not mentioned will be clearly understood by those skilled in the art from the following description of the invention.

Means for Solving the Problems

[0015] A battery cell according to one aspect of the present invention for achieving the above object includes an electrode assembly having a structure in which a first electrode plate, a second electrode plate, and a separator interposed therebetween are wound in one direction, an open portion provided on one side so that the electrode assembly is housed, and a partial closed portion provided on the opposite side thereof, a battery can electrically connected to the second electrode plate, a current collector electrically connected to the first electrode plate, a cell terminal connected to the current collector through a through hole in the closed portion of the battery can, a central hole configured to expose the lower portion of the cell terminal, and an insulator interposed between the battery can and the current collector.

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

[0017] According to one aspect of the present invention, when the electrode assembly is housed in the battery can, the insulator may include a protrusion provided on an outer peripheral surface of the insulator so as to press an inner surface of the battery can.

[0018] Desirably, a plurality of the protrusions may be provided, and the plurality of protrusions may be provided at preset intervals on the outer peripheral surface of the insulator.

[0019] Desirably, the plurality of protrusions may be spaced apart at equal intervals along the circumferential direction on the outer peripheral surface of the insulator.

[0020] According to another aspect of the present invention, when the electrode assembly is housed in the battery can, an adhesive layer may be formed on an upper surface of the insulator that contacts the battery can so that the insulator is fixed to the battery can by adhesion.

[0021] Desirably, the insulator may include a through hole formed in a region between the outer peripheral surface and the central hole.

[0022] In one aspect of the present invention, a distance from the center of the insulator to an end of the protrusion may be larger than a radius of the electrode assembly.

[0023] A distance from the center of the insulator to a region on the outer peripheral surface of the insulator where the protrusion is not formed may be the same as or larger than the radius of the electrode assembly.

[0024] In another aspect of the present invention, a distance from the center of the insulator to an end of the protrusion may be larger than an inner diameter of the battery can.

[0025] The protruding portion may be configured to be elastically pressed inward of the insulator by the inner surface of the battery can.

[0026] Desirably, the insulator may have a thickness corresponding to the distance between the inner surface of the closed portion of the battery can and the current collector plate.

[0027] The insulator may include a protrusion accommodating portion that is spaced in a direction from a position corresponding to the protruding portion toward the center of the insulator.

[0028] The outer portion of the protrusion accommodating portion may have a form that bulges in a direction toward the protruding portion.

[0029] The protrusion accommodating portion may have a length corresponding to the distance from one end to the other end in the circumferential direction of the insulator at the protruding portion.

[0030] The radius of curvature of the outer portion of the protrusion accommodating portion may be smaller than the radius of curvature of the protruding portion.

[0031] Desirably, it may further include a cap plate configured to seal the open portion of the battery can.

[0032] The cap plate is insulated from the battery can and may not have a polarity.

[0033] The technical problem of the present invention can also be achieved by a battery pack including at least one of the above-described battery cells and an automobile including at least one of the battery packs.

Advantages of the Invention

[0034] According to one aspect of the present invention, since the insulator is fixed to the battery can and does not move, when the jelly roll type electrode assembly is later inserted into the battery can, the insulator can be coupled to the jelly roll type electrode assembly at an accurate position, thereby improving the insulation property and preventing the occurrence of defects.

[0035] According to another aspect of the present invention, when the jelly roll type electrode assembly is inserted into the battery can in a free fall manner, the insulator descends at an appropriate speed due to the natural deformation of the protrusion, thereby preventing damage to the electrode assembly. The present invention is applicable not only to a manufacturing facility configured to insert the electrode assembly in a free fall manner from the opening to the closing portion of the battery can, but also when applying to a facility capable of such free fall insertion, the risk of breakage of the electrode assembly and the like can be reduced. In this way, when the constraints in the configuration of the manufacturing facility are reduced, it brings the effect that a simpler and more diverse facility configuration becomes possible, and effects such as downsizing of the facility size, simplification of the facility configuration, and cost reduction can be achieved.

[0036] According to still another aspect of the present invention, it is possible to provide a battery pack with improved capacity and an automobile including the same, which are manufactured using a cylindrical battery cell having an improved structure.

[0037] The following drawings attached to this specification illustrate desirable embodiments of the present invention and serve to further understand the technical idea of the present invention together with the detailed description of the invention. Therefore, the present invention should not be construed as being limited only to the matters described in the drawings.

Brief Description of the Drawings

[0038]

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Embodiments for Carrying Out the Invention

[0039] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. Prior to this, the terms and words used in this specification and the claims should not be construed as being limited to their ordinary or dictionary meanings. The inventor himself must interpret them in accordance with the meaning and concept corresponding to the technical idea of the present invention in accordance with the principle that he can appropriately define the concept of the terms in order to explain the invention in the best way.

[0040] Therefore, it should be understood that the embodiments described in this specification and the configurations shown in the drawings are only one of the most preferred embodiments of the present invention and do not represent all of the technical ideas of the present invention. Therefore, there may be various equivalents and modifications that can replace them at the time of this application.

[0041] Also, for the purpose of assisting in the understanding of the invention, the accompanying drawings may show some components exaggerated rather than at actual scale. Note that the same reference numerals may be assigned to the same components in different embodiments.

[0042] FIG. 1 is a perspective view of a cylindrical battery cell according to an embodiment of the present invention, FIG. 2 is a perspective view showing a cross-section of the central portion of the cylindrical battery cell in FIG. 1, FIG. 3 is a cross-sectional view of a cylindrical battery cell according to an embodiment of the present invention, FIG. 4 is a perspective view of an insulator of a cylindrical battery cell according to an embodiment of the present invention, FIGS. 5 to 7 are modified embodiments of the insulator in FIG. 4, FIG. 8 is a view showing a battery can of a cylindrical battery cell according to an embodiment of the present invention, FIG. 9 is an enlarged view of a cell terminal of a cylindrical battery cell according to an embodiment of the present invention, and FIG. 10 is a cross-sectional view of another embodiment of the cylindrical battery cell in FIG. 3.

[0043] A cylindrical battery cell 10 according to an embodiment of the present invention will be described.

[0044] Desirably, the cylindrical battery cell 10 can be, for example, a cylindrical battery cell 10 having a form factor ratio (a value obtained by dividing the diameter of the cylindrical battery by its height, i.e., the ratio of the diameter Φ to the height H) greater than about 0.4.

[0045] Here, the form factor means a value indicating the diameter and height of the cylindrical battery cell 10. The cylindrical battery cell 10 according to an embodiment of the present invention can 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 represent the diameter of the cell, the next two digits represent the height of the battery, and the last digit 0 indicates that the cross-section of the cell is circular. When the height of the cell exceeds 100 mm, three digits are required to indicate the height of the cell, so the last digit 0 can be omitted.

[0046] The battery cell according to an embodiment of the present invention can be a cylindrical battery cell 10 that is substantially columnar, has a diameter of about 46 mm, a height of about 110 mm, and a form factor ratio of 0.418.

[0047] A battery cell according to another embodiment can be a cylindrical battery cell 10 that is substantially cylindrical, has a diameter of about 48 mm, a height of about 75 mm, and a form factor ratio of 0.640.

[0048] A battery cell according to yet another embodiment can be a cylindrical battery cell 10 that is substantially cylindrical, has a diameter of about 48 mm, a height of about 110 mm, and a form factor ratio of 0.436.

[0049] A battery cell according to yet another embodiment can be a cylindrical battery cell 10 that is substantially cylindrical, has a diameter of about 48 mm, a height of about 80 mm, and a form factor ratio of 0.600.

[0050] A battery cell according to yet another embodiment can be a cylindrical battery cell 10 that is substantially cylindrical, has a diameter of about 46 mm, a height of about 80 mm, and a form factor ratio of 0.575.

[0051] 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.

[0052] Referring to FIGS. 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 plate 300, a cell terminal 400, and an insulator 600. Here, the reference numeral 500 is an insulating tape 500 for insulating the side surface of the electrode assembly 100 as will be described later, and the insulating tape 500 can prevent contact between the current collector plate 300 and the battery can 200. The insulating tape 500 can cover at least the outer peripheral surface of the upper end of the electrode assembly 100.

[0053] The electrode assembly 100 is provided such that the first electrode plate and the second electrode plate are wound in one direction with a separator interposed therebetween. That is, the electrode assembly 100 has a jelly roll type structure in which the first electrode plate, the second electrode plate, and the separator interposed therebetween are wound in one direction. The first electrode plate and the second electrode plate may be, for example, in the form of sheets. The first electrode plate may have a positive or negative polarity, and the second electrode plate has a polarity opposite to that of the first electrode plate. That is, the first electrode plate is a positive electrode plate or a negative electrode plate, and the second electrode plate can be a negative electrode plate or a positive electrode plate having a polarity opposite to that of the first electrode plate. However, hereinafter, for the sake of convenience of explanation, the case where the first electrode plate is a positive electrode and the second electrode plate is a negative electrode plate will be mainly described. On the other hand, a detailed description of the electrode assembly 100 replaces the foregoing description.

[0054] The electrode assembly 100 is configured in various jelly roll types and can be changed. For example, a non-coated portion may be formed on the electrode assembly 100, and the non-coated portion may be used as an electrode tab, or electrode tabs of various shapes can be connected to the non-coated portion in various ways. Hereinafter, for the sake of convenience of explanation, an example in which the non-coated portion is used as an electrode tab will be mainly described, but the electrode assembly 100 can be further variously modified and implemented.

[0055] Referring to FIG. 3, the first electrode plate may include a first non-coated portion 110 where the active material layer is not coated on the long side end. And the second electrode plate may also include a second non-coated portion 120 where the active material layer is not coated on the long side end. That is, at least one of the first electrode plate and the second electrode plate may include a non-coated portion where the active material is not coated along the winding direction at the long side end. The non-coated portion provided on the first electrode plate and the non-coated portion provided on the second electrode plate may be located in opposite directions to each other. For example, the non-coated portion provided on the first electrode plate may have a form extending upward from the electrode assembly 100, and the non-coated portion provided on the second electrode plate may have a form extending downward from the electrode assembly 100.

[0056] Here, the first non-coated portion 110 and the second non-coated portion 120 can be used as electrode tabs themselves by forming a plurality of turns around the center of the electrode assembly 100 and being exposed outside the separator.

[0057] The battery can 200 may have an open portion provided on one side for accommodating the electrode assembly 100 and a partial closing portion provided on the opposite side. The battery can 200 may be electrically connected to the second electrode plate.

[0058] The insulator 600 described above can be coupled to the electrode assembly 100. The insulator 600 may include a central hole configured to expose the lower part of the cell terminal 400. The central hole may be formed at a position corresponding to the winding center of the electrode assembly 100. The insulator 600 may be interposed between the battery can 200 and the current collector plate 300. Desirably, the insulator 600 is configured to cover the upper end of the first non-coated portion 110 for insulation. The insulator 600 prevents contact between the first non-coated portion 110 and the battery can 200. In the case of FIG. 3, the current collector plate 300 is coupled to the upper part of the first non-coated portion 110, and the insulator 600 is coupled to the upper part of the current collector plate 300. That is, the insulator 600 is housed inside the battery can 200, covers at least a part of the electrode assembly 100, and is configured to block the electrical connection between the first non-coated portion 110 and the battery can 200. Here, when the current collector plate 300 is provided on the upper part of the first non-coated portion 110, the insulator 600 is coupled to the current collector plate 300 above the current collector plate 300 to block the electrical connection between the battery can 200 and the current collector plate 300. Therefore, the insulator 600 may be made of an insulating material. Desirably, 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).

[0059] The insulator 600 is interposed between the battery can 200 and the current collector plate 300 so as to cover the upper end portion of the first non-coated portion 110. The insulator 600 can prevent the contact between the first non-coated portion 110 and the battery can 200 and the contact between the current collector plate 300 and the battery can 200 together with the insulating tape 500. That is, the insulator 600 prevents the contact between the upper part of the first non-coated portion 110 and the battery can 200 or between the current collector plate 300 and the battery can 200, and the insulating tape 500 can prevent the contact between the side surface of the electrode assembly 100 and the battery can 200. In particular, the insulating tape 500 can prevent the contact between the side surface of the first non-coated portion 110 and the battery can 200.

[0060] The insulator 600 can 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 shape of the insulator 600 can also be circular.

[0061] The insulator 600 can be coupled to the battery can 200 in various ways. In one embodiment, before the electrode assembly 100 is housed in the battery can 200, the insulator 600 can be coupled to the battery can 200 by an interference fit. For example, referring to FIG. 4, at least one protrusion 610 can be formed on the outer peripheral surface of the insulator 600. The protrusion 610 can be configured to press the inner surface of the battery can 200 when the insulator 600 is housed in the inner surface of the battery can 200.

[0062] Desirably, a plurality of protrusions 610 are provided, and the plurality of protrusions 610 can be formed at preset intervals on the outer peripheral surface of the insulator 600. In FIG. 4, four protrusions 610 are formed, but the present invention is not limited thereto. The protrusions 610 can be provided in various numbers, such as 8, 16, etc. When four protrusions 610 are formed, the four protrusions 610 can be formed at substantially the same intervals along the circumferential direction on the outer peripheral surface of the insulator 600. When the insulator 600 having the protrusions 610 formed on the outer peripheral surface is coupled to the battery can 200, the protrusions 610 are pressed and deformed, so that the insulator 600 can be coupled to the inner surface of the battery can 200 by an interference fit method.

[0063] 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. The distance from the center of the insulator 600 to the region on the outer peripheral surface of the insulator 600 where the protrusion 610 is not formed may be the same as or greater than the radius of the electrode assembly 100. Thereby, the insulator 600 can prevent the contact between the battery can 200 and the electrode assembly 100 by entirely covering one surface of the electrode assembly 100. On the other hand, 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. Thereby, when the insulator 600 is inserted into the battery can 200, the protrusion 610 is pressed, so that the insulator 600 can be coupled to the battery can 200 in an interference fit manner. For example, the protrusion 610 may be configured to be elastically pressed toward the inside of the insulator 600 by the inner surface of the battery can 200 when the insulator 600 is inserted into the battery can 200.

[0064] On the other hand, the insulator 600 may include a protrusion accommodating portion 630 for allowing the protrusion 610 to be naturally pressed inward when the insulator 600 is inserted into the battery can 200. A plurality of the protrusion accommodating portions 630 may be provided. The protrusion accommodating portions 630 may be provided in the same number as the protrusions 610. In this case, the plurality of protrusion accommodating portions 630 may be provided at positions adjacent to the respective protrusions 610. The protrusion accommodating portion 630 may be a vacant space partially formed in the insulator 600 by a slit.

[0065] By providing the protrusion accommodating portion 630, when the insulator 600 is inserted into the battery can 200, it can move naturally from the open portion of the battery can 200 toward the closed portion side without applying excessive force. As a result, when the electrode assembly 100 is inserted into the battery can 200, for example, in a free-fall manner, the insulator 600 descends at an appropriate speed due to the natural deformation of the protrusions, thereby preventing damage to the electrode assembly 100. Therefore, the present invention is applicable not only to manufacturing equipment configured to insert the electrode assembly 100 in a free-fall manner from the opening of the battery can toward the closed portion, but also to equipment capable of such free-fall insertion, and it is possible to reduce the risk of damage to the electrode assembly 100 when applied to such equipment. In this way, when the constraints in the configuration of the manufacturing equipment are reduced, it brings the effect of enabling a simpler and more diverse equipment configuration, and it is possible to expect effects such as downsizing of the equipment size, simplification of the equipment configuration, and cost reduction.

[0066] Also, in the present invention, when the protrusion accommodating portion 630 is applied, when the protrusion 610 is pressed by the inner surface of the battery can 200, the protrusion accommodating portion 630 can minimize the phenomenon of force being transmitted in the direction of the central hole of the insulator 600 by accommodating the protrusion 610 that undergoes morphological deformation toward the inside of the insulator 600. When the force due to the pressing of the protrusion 610 is buffered by the protrusion accommodating portion 630 in this way, it is possible to prevent the occurrence of morphological deformation and / or size change of the central hole of the insulator 600.

[0067] The protrusion accommodating portion 630 may be located at a position corresponding to the protrusion 610 and spaced apart in the direction toward the center of the insulator 600. The outer portion of the protrusion accommodating portion 630 may have a bulged shape in the direction toward the protrusion 610. The protrusion accommodating portion 630 may have a length corresponding to the distance from one end portion to the other end portion in the circumferential direction of the insulator 600 at the protrusion 610. That is, the protrusion accommodating portion 630 may be configured to buffer the pressing force of the protrusion 610 over the entire region where the protrusion 610 is formed.

[0068] The radius of curvature of the outer portion of the protrusion accommodating portion 630 may be smaller than the radius of curvature of the protrusion portion 610. In this case, compression of the protrusion portion 610 becomes easier at the end portion of the protrusion portion 610, that is, at the central portion in the circumferential direction of the protrusion portion 610, and thereby the process of inserting the insulator 600 into the battery can 200 can be smoothed.

[0069] On the other hand, when the insulator 600 includes both the through hole 620 and the protrusion accommodating slit 610, the distance from the protrusion portion 610 to the protrusion accommodating slit 610 can be formed closer than the distance from the protrusion portion 610 to the through hole 620.

[0070] As another embodiment, a heat welding layer may be formed on the insulator 600 so that the insulator 600 is fixed to the battery can 200 by heat welding. That is, before the electrode assembly 100 is housed in the battery can 200, after the insulator 600 is inserted into the battery can 200, it can be fixed by heat welding by hot air injection or heating.

[0071] As still another embodiment, 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 can be coupled to the battery can 200 by the adhesive layer formed on the upper surface of the insulator 600.

[0072] As still another embodiment, the insulator 600 can be fixed to the battery can 200 by a double-sided tape.

[0073] Thus, 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 can be coupled to the exact position of the jelly roll type electrode assembly 100, so that the insulation of the cylindrical battery cell is improved and the occurrence of defects is prevented.

[0074] 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 insulation performance may deteriorate. If the insulator 600 is too thick, it may occupy the internal space of the battery can 200, reducing the capacity of the battery cell and increasing the cost. Therefore, the insulator 600 may have a thickness of 0.8 mm or more and 1.6 mm or less, desirably 1.0 mm to 1.4 mm, so as to maintain appropriate insulation performance and not reduce the capacity of the battery cell. However, the thickness of the insulator 600 is not limited to this.

[0075] Referring to FIG. 4, the insulator 600 may include at least one through hole 620 formed in a region between the outer peripheral surface and the central hole. The through hole 620 may function as a movement path for the electrolyte. Also, during the process of inserting the insulator 600 into the battery can 200 and moving it from the open portion side to the closed portion side, the through hole 620 can prevent the phenomenon that the space between the insulator 600 and the closed portion of the battery can 200 is sealed and air is compressed, thereby facilitating the smooth insertion of the insulator 600. Here, when the electrolyte is injected into the battery can 200, the insulator 600 may be arranged to be placed at the bottom. That is, the electrolyte may be injected into the battery can 200 in a state where the top and bottom of the cylindrical battery cell 10 in FIG. 3 are inverted, that is, with the cell terminal 400 positioned downward.

[0076] Then, referring to the arrow in FIG. 7, after the electrolyte moves downward through the central portion of the insulator 600 in the direction of arrow a1 (the direction in which the electrolyte is injected), it moves along the bottom of the insulator 600 in the direction of arrow a2 and then moves upward from the through hole 620 in the direction of arrow a3, thereby providing the electrolyte to the electrode assembly 100. At this time, when the through hole 620 is formed in the insulator 600, it is possible to smoothly and easily provide the electrolyte to the electrode assembly 100.

[0077] A plurality of through-holes 620 are formed, and the plurality of through-holes 620 can be spaced apart at a preset interval. Referring to FIG. 4, the plurality of through-holes 620 can be arranged on any one straight line from the center of the insulator 600 toward the outer peripheral surface of the insulator 600. In FIGS. 4 and 7, three through-holes 620 are arranged for each straight line with respect to a plurality of straight lines radially arranged from the center of the insulator 600 toward the outer peripheral surface of the insulator 600. However, the number, shape, and / or arrangement of the through-holes 620 are not limited thereto.

[0078] As a modified embodiment, referring to FIG. 5, the diameters of the through-holes 620 arranged in the radial direction of the insulator 600 can be the same or different. In one example, the diameter of the through-hole 620 can be the same from the center to the edge, or can increase or decrease. Since the electrolytic solution moves from the center of the insulator 600 to the edge, the amount of movement of the electrolytic solution in the direction of arrow a3 increases as it gets closer to the center of the insulator 600. Therefore, the size of the through-hole 620 can be increased as it advances toward the edge of the insulator 600 to adjust the overall movement amount of the electrolytic solution to be similar. However, if necessary, the size of the through-hole 620 can be decreased as it advances toward the edge of the insulator 600.

[0079] As yet another modified embodiment, referring to FIG. 6, the intervals at which the plurality of through-holes 620 are arranged in the radial direction of the insulator 600 can be the same or different. In one example, the arrangement interval of the through-holes 620 can increase or decrease as it advances from the center to the edge.

[0080] Here, the diameter of the through-hole is 1.0 mm to 3.0 mm, and desirably can be 1.2 mm to 1.7 mm.

[0081] The edge portion of the insulator 600 may have a cross-sectional shape corresponding to the cross-sectional shape of the corner of the closing portion 210 of the battery can 200. In one example, when the cross-section of the corner of the closing portion 210 of the battery can 200 is round, the edge portion of the insulator 600 may also have a round shape so as to correspond to the round cross-section of the corner of the closing portion 210 of the battery can 200.

[0082] Desirably, the insulator 600 may have a thickness corresponding to the distance between the inner surface of the closing portion 210 of the battery can 200 and the current collector plate 300. In one example, the upper portion of the insulator 600 may contact the inner surface of the closing portion 210 of the battery can 200, and the 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.

[0083] The insulator 600 may include, for example, an elastic material. Thereby, when vibration or an external impact is applied to the cylindrical battery cell 10, the insulator 600 can absorb the impact in the process of returning to its original state after being compressed by elasticity. Therefore, even when vibration or an external impact is applied to the battery cell, damage to the internal components of the battery cell can be minimized.

[0084] The insulator 600 is provided with a central hole having a preset diameter at the center, and the central hole can expose the lower portion of the cell terminal 400. For example, the insulator 600 may be provided with a substantially circular central hole adjacent to the winding center. Due to the presence of the central hole, the cell terminal 400 can be in a state where it can contact the current collector plate 300 or the first non-coated portion 110. Desirably, the central hole has a diameter capable of exposing the lower portion of the cell terminal 400.

[0085] The insulating tape 500 can be attached to the outer peripheral surface of the electrode assembly 100 at least up to a point corresponding to the edge portion of the insulator 600. The insulating tape 500 can be a double-sided tape or a single-sided tape. Note that the present invention is not limited to the insulating tape, and a heat shrinkable tube may be coupled to the outer peripheral surface of the electrode assembly 100.

[0086] The first electrode plate has the first electrode active material coated on one or both sides. And at the end of the first electrode plate, there is a first non-coated portion 110 where the first electrode active material is not coated.

[0087] The second electrode plate has the second electrode active material coated on one or both sides. And at the end of the second electrode plate, there is a second non-coated portion 120 where the second electrode active material is not coated.

[0088] And the first non-coated portion 110 of the first electrode plate and the second non-coated portion 120 of the second electrode plate are provided so as to face in opposite directions when wound in the electrode assembly. The first non-coated portion 110 extends toward the closed portion 210 of the battery can 200, and the second non-coated portion 120 extends toward the open portion 220 of the battery can 200.

[0089] In the present invention, the positive electrode active material coated on the positive electrode plate and the negative electrode active material coated on the negative electrode plate can be used without limitation as long as they are active materials known in the art.

[0090] In one example, the positive electrode active material may include an alkali metal compound represented by the general chemical formula A[A x M y O 2+z (A includes at least one or more elements of Li, Na, and K; M includes at least one or more elements selected from Ni, Co, Mn, Ca, Mg, Al, Ti, Si, Fe, Mo, V, Zr, Zn, Cu, Mo, Sc, Zr, Ru, and Cr; x≧0, 1≦x + y≦2, -0.1≦z≦2; the stoichiometric coefficients x, y, and z of the chemical theory are selected so that the compound maintains electrical neutrality.)

[0091] In another example, the positive electrode active material is an alkali metal compound xLiM 1 O2-(1 - x)Li2M 2 O3 (M 1 includes at least one or more elements having an average oxidation state of 3; M 2contains at least one or more elements having an average oxidation state of 4; 0 ≦ x ≦ 1) can be.

[0092] In yet 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 or more elements selected from Ti, Si, Mn, Co, Fe, V, Cr, Mo, Ni, Nd, Mg, and Al; M 2 contains at least one or more elements selected from Ti, Si, Mn, Co, Fe, V, Cr, Mo, Ni, Nd, 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 Li3M2(PO4)3 [M contains at least one element selected from Ti, Si, Mn, Fe, Co, V, Cr, Mo, Ni, Mg, and Al.], and can be a lithium metal phosphate represented by.

[0093] Desirably, the positive electrode active material may contain primary particles and / or secondary particles aggregated from the primary particles.

[0094] In one example, as the negative electrode active material, a carbon material, a lithium metal or a lithium metal compound, silicon or a silicon compound, tin or a tin compound, etc. can be used. Metal oxides such as TiO2 and SnO2 having a potential of less than 2V can also be used as the negative electrode active material. As the carbon material, low-crystalline carbon, high-crystalline carbon, etc. can all be used.

[0095] The separation membrane can be used alone or in a laminated form, which is a porous polymer film, for example, a porous polymer film made from polyolefin-based polymers such as homopolymers of ethylene, propylene, ethylene / butene copolymers, ethylene / hexene copolymers, ethylene / methacrylate copolymers, etc. In other examples, the separation membrane can use ordinary porous non-woven fabrics, for example, non-woven fabrics made of high melting point glass fibers, polyethylene terephthalate fibers, etc.

[0096] At least one surface of the separation membrane may include a coating layer of inorganic particles. It is also possible that the separation membrane itself consists of a coating layer of inorganic particles. The particles constituting the coating layer may have a structure in which they are combined with a binder so that an interstitial volume exists between adjacent particles.

[0097] The inorganic particles can be composed of an inorganic substance having a dielectric constant of 5 or more. As this non-limiting example, the inorganic particles may include at least one or more substances selected from the group consisting 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.

[0098] The electrolyte can be a salt having a structure such as A + B - . Here, A + includes ions composed of alkali metal cations such as Li + , Na + , K + or combinations thereof. And B - is F - , Cl - , Br - , I - , NO3 -, N(CN)2 - , BF4 - , ClO4 - , AlO4 - , AlCl4 - , PF6 - , SbF6 - , AsF6 - , BF2C2O4 - , BC4O8 - , (CF3)2PF4 - , (CF3)3PF3 - , (CF3)4PF2 - , (CF3)5PF - , (CF3)6P - , CF3SO3 - , C4F9SO3 - , CF3CF2SO3 - , (CF3SO2)2N - , (FSO2)2N - , CF3CF2(CF3)2CO - , (CF3SO2)2CH - , (SF5)3C - , (CF3SO2)3C - , CF3(CF2)7SO3 - , CF3CO2 - , CH3CO2 - , SCN− and (CF3CF2SO2)2N - It contains any one or more anions selected from the group consisting of

[0099] Further, the electrolyte can be used by dissolving it in an organic solvent. Examples of the organic solvent include propylene carbonate (PC), ethylene carbonate (EC), diethyl carbonate (DEC), dimethyl carbonate (DMC), dipropyl carbonate (DPC), dimethyl sulfoxide, acetonitrile, dimethoxyethane, diethoxyethane, tetrahydrofuran, N-methyl-2-pyrrolidone (NMP), ethyl methyl carbonate (EMC), γ-butyrolactone, or a mixture thereof may be used.

[0100] The battery can 200 is formed in a cylindrical shape and houses the electrode assembly 100, and is electrically connected to the second electrode plate of the electrode assembly 100. As a result, the battery can 200 can have the same polarity as the second electrode plate. That is, when the second electrode plate is the negative electrode, the battery can 200 also has a negative electrode.

[0101] If the size of the electrode assembly 100 is increased while the size of the battery can 200 is determined by the standard, the overall capacity of the battery cell increases, but the distance between the battery can 200 and the electrode assembly 100 decreases.

[0102] That is, in order to increase the overall capacity of the battery cell, when the size of the electrode assembly 100 is increased, the distance between the battery can 200 and the electrode assembly 100 decreases. Therefore, in order to increase the capacity of the battery cell, it is necessary to interpose an insulator 600 between the reduced compartments of the battery can 200 and the electrode assembly 100. For this purpose, it is desirable that the thickness of the insulator 600 be as thin as possible.

[0103] Referring to FIG. 8, a closed portion 210 and an open portion 220 may be formed on the battery can 200 so as to face each other.

[0104] For example, with reference to FIG. 8, an open portion 220 may be formed at the lower part of the battery can 200. The electrode assembly 100 is accommodated in the battery can 200 from the open portion 220 formed at the lower part, and the electrolyte is also injected from the open portion 220 formed at the lower part of the battery can 200. When injecting the electrolyte, the battery can 200 can be turned upside down so that the open portion 220 faces upward.

[0105] That is, the battery can 200 is a substantially cylindrical container with an open portion 220 formed at the lower part, and is made of a conductive material such as metal, for example. The material of the battery can 200 may be, for example, a conductive metal such as aluminum, steel, stainless steel, etc., but is not limited thereto. A Ni coating layer may be selectively formed on the surface of the battery can 200.

[0106] Also, with reference to FIG. 8, a closed portion 210 may be formed at the upper part of the battery can 200. A through hole 211 is formed in the closed portion 210, and the cell terminal 400 can be coupled to the through hole 211 as shown in FIG. 3.

[0107] A beading portion 240 and a crimping portion 250 may be formed at the lower part of the battery can 200. The beading portion 240 is formed by pressing the outer peripheral surface of the battery can 200 inward around a region adjacent to the open portion 220 of the battery can 200.

[0108] The beading portion 240 supports the electrode assembly 100 so that the electrode assembly 100 having a size substantially corresponding to the width of the battery can 200 does not come out from the open portion 220 formed at the lower part of the battery can 200, and can also function as a support portion for providing the cap plate 230. Also, the beading portion 240 supports the outer peripheral surface of the sealing gasket 260.

[0109] The crimping portion 250 extends inside the battery can 200 and is bent to surround and fix the peripheral edge of the cap plate 230 together with the sealing gasket 260. Here, the crimping portion 250 is formed at the lower part of the battery can 200 based on the state in which the battery can 200 is disposed. For example, when the battery can 200 is disposed such that the cell terminal 400 is located at the upper part as shown in FIG. 3, the crimping portion 250 is formed at the lower part of the battery can 200 with reference to FIG. 3. And, as shown in FIG. 3, the crimping portion 250 is formed below the beading portion 240.

[0110] However, the present invention does not exclude the 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, or the fixing of the cap plate 230, or the sealing of the battery can 200 can be realized by at least one of the additional application of a component that can function as a stopper for the electrode assembly 100, the additional application of a structure in which the cap plate 230 can be provided, and the welding of the battery can 200 and the cap plate 230.

[0111] With reference to FIG. 3, the crimping portion 250 is formed below the beading portion 240. The crimping portion 250 has a form that extends and is bent so as to surround the peripheral edge of the cap plate 230 disposed below the beading portion 240. Due to the shape of the crimping portion 250 bent in this way, the cap plate 230 is fixed to the beading portion 21. Of course, such a crimping portion 250 may be omitted, and the cap plate 230 may be fixed while covering the open portion of the battery can 200 by another fixing structure. For example, in Korean Patent Publication No. 10-2019-0030016A of the present applicant, a cylindrical battery cell in which the beading portion is omitted is disclosed, and such a structure may be adopted in the present invention.

[0112] The current collector plate 300 is electrically connected to the first electrode plate above the electrode assembly 100.

[0113] The current collector plate 300 is made of a conductive metal material and is connected to the first non-coated portion 110 of the electrode assembly 100.

[0114] The current collector plate 300 can be coupled to a coupling surface formed by bending the end of the first non-coated portion 110 in a direction parallel to the current collector plate 300. The bending direction of the first non-coated portion 110 can be, for example, a direction toward the winding center portion of the electrode assembly 100.

[0115] When the first non-coated portion 110 has such a bent form, the space occupied by the first non-coated portion 110 can be reduced to improve the energy density. Also, by increasing the bonding area between the first non-coated portion 110 and the current collector plate 300, the bonding force can be improved and the resistance can be reduced.

[0116] The cell terminal 400 is made of a conductive metal material (e.g., aluminum), is coupled to a through hole 211 formed in the closing portion 210 of the battery can 200, and is electrically connected to the current collector plate 300. And the cell terminal 400 is electrically connected to the first electrode plate of the electrode assembly 100 via the current collector plate 300 and thereby has a positive polarity. That is, the cell terminal 400 can function as a positive electrode terminal which is a first electrode terminal. And the battery can 200 is electrically connected to the second electrode plate of the electrode assembly 100 as described above and thereby has a negative polarity.

[0117] The cell terminal 400 may include a terminal insertion portion 410. The terminal insertion portion 410 is inserted into the battery can 200 from a through hole 211 formed in the closing portion 210 of the battery can 200, and the lower end portion can be electrically connected to the central portion of the current collector plate 300. The electrical connection can be performed by welding. The welding can be laser welding, ultrasonic welding, resistance welding, etc.

[0118] The terminal insertion part 410 can penetrate through the battery can 200 and the insulator 600 simultaneously and be coupled to the current collector plate 300. The peripheral part at the lower portion of the terminal insertion part 410 can be pressed by a caulking jig, and the cell terminal 400 can be riveted toward the inner surface of the upper end part of the battery can 200 and firmly fixed to the through hole.

[0119] That is, the peripheral part at the lower portion of the terminal insertion part 410 can have a form that is bent toward the inner surface of the battery can 200 by the application of the caulking jig. For this reason, the maximum width of the end part of the terminal insertion part 410 can be formed larger than the maximum width of the hole formed in the battery can 200 by the penetration of the terminal insertion part 410.

[0120] Referring to FIG. 9, the riveting structure of the cell terminal 400 can include a cylindrical battery can 200 with one side open, a cell terminal 400 riveted through a through hole 211 formed in the bottom part 52 of the battery can 200, and a rivet gasket 54 interposed between the cell terminal 400 and the through hole 211.

[0121] The rivet gasket 54 can be made of an insulating and elastic polymer resin. In one example, the rivet gasket 54 can be made of polypropylene, polybutylene terephthalate, polytetrafluoroethylene, etc., but the present invention is not limited thereto. The rivet gasket 54 can include an external gasket 54a interposed between the external flange part 50b and the outer surface 52a of the bottom part 52 of the battery can 200, and an internal gasket 54b interposed between the internal flange part 50c and the inner surface 52b of the bottom part 52 of the battery can 200. Desirably, the external gasket 54a and the internal gasket 54b are separated with reference to the outer surface 52a of the bottom part of the battery can 200.

[0122] On the other hand, as another embodiment, the terminal insertion part 410 may not have a form that is bent toward the inner surface of the battery can 200. For example, referring to FIG. 10, the terminal insertion part 410 can be substantially cylindrical and penetrate through a hole located at substantially the center of the upper surface of the battery can 200.

[0123] In one 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 be, for example, polygonal, star-shaped, or have a shape with branches extending from the center.

[0124] The terminal insertion portion 410 of the cell terminal 400 may penetrate the central hole of the insulator 600. The diameter of the central hole of the insulator 600 may be larger than or the same as the diameter of the terminal insertion portion 410. And the terminal insertion portion 410 of the cell terminal 400 may penetrate the central hole of the insulator 600 and be electrically coupled to the current collector plate 300.

[0125] The insulator 600 is interposed between the battery can 200 and the electrode assembly 100, and in FIG. 3, between the current collector plate 300 at the upper part of the electrode assembly 100 and the battery can 200. For a specific description of the insulator 600, the description of the insulator 600 of the electrode assembly 100 according to one embodiment of the present invention described above shall be substituted.

[0126] Referring to FIG. 3, the cap plate 230 is configured to seal the opening portion 220 of the battery can 200. The cap plate 230 may be made of, for example, a metal material in order to ensure rigidity.

[0127] The cap plate 230 seals the opening portion 220 formed at the lower end of the battery can 200. The cap plate 230 may be separated from the electrode assembly 100 and provided non-polar. That is, the cap plate 230 may not have a polarity even when provided with a conductive metal material. The fact that the cap plate 230 does not have a polarity means that the cap plate 230 is electrically insulated from the battery can 200 and the cell terminal 400. Thus, the cap plate 230 may not have a polarity, and its material does not necessarily have to be a conductive metal.

[0128] The cap plate 230 can be provided and supported on the beading portion 240 formed on the battery can 200. Further, the cap plate 230 is fixed by the crimping portion 250. A sealing gasket 260 can be interposed between the cap plate 230 and the crimping portion 250 of the battery can 200 to ensure the airtightness of the battery can 200. That is, the sealing gasket 260 can be provided so as to be interposed between the peripheral edge portion of the cap plate 230 and the opening portion 220 of the battery can 200.

[0129] On the other hand, 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 can be interposed between the cap plate 230 and a fixing structure provided on the opening portion 220 side of the battery can 200 to ensure the airtightness of the battery can 200.

[0130] The vent notch 231 can be formed in the cap plate 230 so as to rupture when the pressure inside the battery can 200 exceeds a critical value.

[0131] For example, the vent notch 231 may be formed on both sides of the cap plate 230, and can 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. Further, the vent notch 231 can be formed in various other patterns.

[0132] The vent notch 231 is formed at the lower end of the battery can 200 based on the arrangement state of the battery can 200, and can be provided such that when the vent notch 231 ruptures, the gas inside the battery can 200 is discharged from the lower end of the battery can 200.

[0133] For example, as shown in FIG. 3, when the battery can 200 is arranged such that the cell terminal 400 is located at the upper end, the vent notch 231 can be formed at the lower end of the battery can 200 with reference to FIG. 3.

[0134] The vent notch 231 can be formed as a region having a thickness thinner than that of the peripheral region in the cap plate 230.

[0135] Since the vent notch 231 is thinner than the peripheral region, it is more easily broken than the peripheral region. When the internal pressure of the battery can 200 increases above a certain level, the vent notch 231 breaks, and the gas generated inside the battery can 200 can be discharged.

[0136] For example, the vent notch 231 can be formed by making a cut (notching) on one or both sides of the cap plate 230 to partially reduce the thickness of the battery can 200.

[0137] The cylindrical battery cell 10 according to an embodiment of the present invention can have a structure in which both the positive terminal and the negative terminal are present at the upper part, whereby the upper structure becomes more complex than the lower structure.

[0138] Therefore, for the smooth discharge of the gas generated inside the battery can 200, the vent notch 231 can be formed in the cap plate 230 forming the lower surface of the cylindrical battery cell 10.

[0139] In this way, when the gas generated inside the battery can 200 provided in the cylindrical battery cell 10 is discharged downward, it can also be advantageous for the safety of the user. For example, when the cylindrical battery cell 10 is arranged directly below the driver's seat of an electric vehicle, if the gas is discharged upward, there may be a risk of a safety accident for the driver.

[0140] However, when the gas is discharged downward from the battery can 200 like the cylindrical battery cell 10 according to an embodiment of the present invention, the above-mentioned problems do not occur even if the cylindrical battery cell 10 is arranged directly below the driver's seat in an electric vehicle.

[0141] Referring to FIG. 3, it is desirable that the lower end portion of the cap plate 230 is located above the lower end portion of the battery can 200. In this case, even if the lower end portion of the battery can 200 contacts the ground or the bottom surface of the housing for the module or pack configuration, the cap plate 230 will not contact the ground or the bottom surface of the housing for the module or pack configuration.

[0142] Therefore, it is possible to prevent a phenomenon in which the pressure required for breaking the vent notch 231 differs from the design value due to the weight of the cylindrical battery cell 10, thereby ensuring the smoothness of the breaking of the vent notch 231.

[0143] Referring to FIG. 3, the lower current collector plate 700 is coupled to the lower portion of the electrode assembly 100. The lower current collector plate 700 is made of a conductive metal material such as aluminum, steel, copper, nickel, etc., and is electrically connected to the second non-coated portion 120 of the second electrode plate.

[0144] Desirably, the lower current collector plate 700 is electrically connected to the battery can 200. For this purpose, at least a part of the edge of the lower current collector plate 700 can be interposed and fixed between the inner surface of the battery can 200 and the sealing gasket 260.

[0145] In one embodiment, at least a part of the edge of the lower current collector plate 700 can be fixed to the beading portion 240 by welding while being supported on the lower surface of the beading portion 240 formed at the lower end of the battery can 200. In a modified embodiment, at least a part of the edge of the lower current collector plate 700 can be directly welded to the inner wall surface of the battery can 200.

[0146] Desirably, at least a part of the remaining portion of the lower current collector plate 700 excluding the joint portion of the beading portion can be joined to the folded surface of the second non-coated portion 120 by welding, for example, laser welding.

[0147] Desirably, at least a part of the edge of the lower current collector plate 700 can be electrically connected to the surface adjacent to the crimping portion 250 among the upper and lower surfaces of the beading portion 240.

[0148] On the one hand, 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 may include a first non-coated portion 110, and the second electrode plate may include a second non-coated portion 120. And at least a partial section of the first non-coated portion 110 and / or the second non-coated portion 120 may be divided into a plurality of segmented pieces, and the structure of the segmented pieces will be described in detail below.

[0149] FIG. 11 is a plan view showing the structure of an electrode plate according to an embodiment of the present invention.

[0150] Referring to FIG. 11, in the non-coated portion 43 of the electrode plate 60, the heights of the core-side non-coated portion B1 and the outer-periphery-side non-coated portion B3 are 0 or more and are relatively smaller than that of the intermediate non-coated portion B2. Also, the heights of the core-side non-coated portion B1 and the outer-periphery-side non-coated portion B3 may be the same or different.

[0151] Desirably, at least a partial section of the intermediate non-coated portion B2 may include a plurality of segmented pieces 61. The plurality of segmented pieces 61 may increase in height step by step from the core side to the outer-periphery side.

[0152] The segmented piece 61 may be notched by a laser. The segmented piece 61 may be formed by a known metal foil cutting process such as ultrasonic cutting or punching.

[0153] In FIG. 11, in order to prevent damage to the active material layer 42 and / or the insulating coating layer 44 during the bending process of the non-coated portion 43, it is desirable to provide a predetermined gap between the lower end of the cutting line (C4 in FIG. 10) between the segmented pieces 61 and the active material layer 42. This is because when the non-coated portion 43 is bent, stress concentrates near the lower end of the cutting line. The gap is preferably 0.2 to 4 mm. When the gap is adjusted within such a 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 the stress generated during the bending process of the non-coated portion 43. Also, the gap can prevent damage to the active material layer 42 and / or the insulating coating layer 44 due to the tolerance during notching or cutting of the segmented pieces 61. Desirably, when the electrode plate 60 is wound, at least a part of the insulating coating layer 44 can be exposed outside the separator film. In this case, the insulating coating layer 44 can support the bending point when the segmented piece 61 is bent.

[0154] The plurality of segmented pieces 61 can form a plurality of segmented piece groups as going from the core side to the outer peripheral side. At least one or more of the width, height, and separation pitch of the segmented pieces belonging to the same segmented piece group can be substantially the same.

[0155] FIG. 12 is a diagram showing the definitions of the width, height, and separation pitch of the segmented piece 61 according to an embodiment of the present invention. Referring to FIG. 12, the width C1, height C2, and separation pitch C3 of the segmented piece 61 are designed to prevent the non-coated portion 43 from being torn and to improve the welding strength by sufficiently increasing the number of overlapping layers of the non-coated portion 43 to prevent abnormal deformation of the non-coated portion 43 during the bending process of the non-coated portion 43. Abnormal deformation means that the non-coated portion below the bending point cannot maintain a linear state and collapses and is deformed irregularly.

[0156] Preferably, the width C1 of the segmented piece 61 can be adjusted within the range of 1 to 8 mm. If C1 is less than 1 mm, when the segmented piece 61 is bent toward the core side, a region or space (gap) that does not overlap enough to ensure sufficient welding strength will occur. On the other hand, if C1 exceeds 8 mm, when the segmented piece 61 is bent, the non-coated portion 43 near the bending point may be torn by stress.

[0157] Also, the height of the segmented piece 61 can be adjusted within the range of 2 to 10 mm. If C2 is less than 2 mm, when the segmented piece 61 is bent toward the core side, a region or space (gap) that does not overlap enough to ensure sufficient welding strength will occur. On the other hand, if C2 exceeds 10 mm, it is difficult to manufacture the electrode plate while maintaining the flatness of the non-coated portion uniformly in the winding direction (X direction). That is, the height of the non-coated portion is too large and undulations occur. Further, the separation pitch C3 of the segmented pieces 61 can be adjusted within the range of 0.05 to 1 mm. If C3 is less than 0.05 mm, when the segmented piece 61 is bent, the non-coated portion 43 near the bending point may be torn by stress. On the other hand, if C3 exceeds 1 mm, a region or space (gap) where the segmented pieces 61 do not overlap enough to ensure sufficient welding strength may occur when the segmented piece 61 is bent.

[0158] Referring to FIG. 12, a cutting portion 62 is interposed between two adjacent segmented pieces 61 in the winding direction (X direction). The cutting portion 62 is a space generated by removing the non-coated portion 43. Preferably, the corner portion at the lower end of the cutting portion 62 may have a round shape (see partial enlargement). The round shape can relieve the stress applied to the lower end of the cutting portion 62 during the winding of the electrode plate 60 and / or the bending of the segmented piece 61.

[0159] Referring further to FIG. 11, the width d of the non-coated portion B1 on the core side B1 is designed by applying the condition that the cavity of the core of the electrode assembly is not blocked when the segmented piece 61 of the intermediate non-coated portion B2 is bent toward the core side.

[0160] In one example, the width d of the non-coated portion B1 on the core side B1It can increase in proportion to the bending length of the segmented piece 61 in Group 1. The bending length is the height of the segmented piece 61 with reference to the bending point (63 in FIG. 10). Referring to FIG. 10, C4 indicates the lowest point of the position where bending is possible. The bending point can 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 segmented piece 61. Specifically, the bending point can be set at a predetermined point of the height C2 of the segmented piece 61 with reference to C4. The predetermined point prevents the stress generated during the bending of the segmented piece 61 from causing physical damage to the active material layer 42 or the insulating coating layer 44, and ensures a sufficient number of layers that overlap in the radial direction when the segmented piece 61 is bent in the radial direction of the electrode assembly, so that sufficient welding strength can be ensured when the current collecting plate is welded to the bent region of the segmented piece 61.

[0161] In a specific example, when the electrode plate 60 is used to manufacture an electrode assembly of a cylindrical cell with a form factor of 46800, the width d of the non-coated portion B1 on the core side B1 can be set to 180 to 350 mm according to the diameter of the electrode assembly core.

[0162] In one embodiment, the width of each segmented piece group can be designed to constitute the same winding turn of the electrode assembly.

[0163] Here, the winding turn can be counted with reference to the end of the non-coated portion B1 on the core side when the electrode plate 60 is in a wound state.

[0164] In other variations, the width of each segmented piece group can be designed to constitute at least one or more winding turns of the electrode assembly.

[0165] In still other variations, the width and / or height and / or separation pitch of the segmented pieces 61 belonging to the same segmented piece group can increase or decrease gradually and / or stepwise and / or irregularly within the group.

[0166] Groups 1 to 8 are merely an example of the segmented piece group. The number of groups, the number of segmented pieces 61 included in each group, and the width of the group can be preferably adjusted so that the segmented pieces 61 are overlapped multiple times to maximize the dispersion of stress during the bending process of the non-coated portion 43 and sufficiently ensure the welding strength.

[0167] In other modifications, the height of the outer peripheral non-coated portion B3 may gradually or stepwise decrease.

[0168] Also, in other modifications, the segmented structure of the intermediate non-coated portion B2 can be extended to the outer peripheral non-coated portion B3 (see the dotted line). In this case, the outer peripheral non-coated portion B3 may also include a plurality of segmented pieces similar to the intermediate non-coated portion B2. In this case, the segmented pieces of the outer peripheral non-coated portion B3 may have a larger width and / or height and / or separation pitch than the intermediate non-coated portion B2. Optionally, the segmented structure of the outer peripheral non-coated portion B3 may be substantially the same as the segmented piece group existing on the outermost side of the intermediate non-coated portion B2.

[0169] In a specific embodiment, when the electrode plate 60 is used to manufacture an electrode assembly of a cylindrical cell with a form factor of 46800, the width d of the core side non-coated portion B1 B1 can be 180 to 350 mm. The width of Group 1 can be 35 to 40% of the width of the core side non-coated portion B1. The width of Group 2 can be 130 to 150% of the width of Group 1. The width of Group 3 can be 120 to 135% of the width of Group 2. The width of Group 4 can be 85 to 90% of the width of Group 3. The width of Group 5 can be 120 to 130% of the width of Group 4. The width of Group 6 can be 100 to 120% of the width of Group 5. The width of Group 7 can be 90 to 120% of the width of Group 6. The width of Group 8 can be 115 to 130% of the width of Group 7. The width d of the outer peripheral non-coated portion B3 B3 can be the same as the width of the core side non-coated portion B1, i.e., 180 to 350 mm.

[0170] The reason why the widths of Groups 1 to 8 do not show a constant increase or decrease pattern is that the width of the segmented pieces gradually increases as it progresses from Group 1 to Group 8, but the number of segmented pieces included in each group is limited to an integer. Therefore, in a specific segmented piece group, the number of segmented pieces can decrease. Thus, the width of the group can show an irregular change pattern as it progresses from the core side to the outer peripheral side, as in the above example.

[0171] That is, when the winding direction widths for each of three consecutively adjacent segmented piece groups in the circumferential direction of the electrode assembly are defined as W1, W2, and W3, respectively, it may include a combination of segmented piece groups where W3 / W2 is smaller than W2 / W1.

[0172] In the above specific example, Groups 4 to 6 correspond to this. The ratio of the width of Group 5 to Group 4 is 120 - 130%, and the ratio of the width of Group 6 to Group 5 is 100 - 120%, and its value is smaller than 120 - 130%.

[0173] 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 view showing the definition of the width, height, and separation pitch of the segmented pieces according to FIG. 13.

[0174] Referring to FIG. 13, the electrode plate 70 has substantially the same configuration as that of FIG. 11, except that the shape of the segmented piece 61' is changed from a quadrangle to a trapezoid.

[0175] FIG. 14 shows the definition of the width, height, and separation pitch of the trapezoidal segmented piece 61'.

[0176] Referring to FIG. 14, the width D1, height D2, and separation pitch D3 of the segmented piece 61' are designed to prevent the non-coated portion 43 near the bending point from breaking during the bending process of the non-coated portion 43 and to prevent abnormal deformation of the non-coated portion 43 while sufficiently increasing the number of overlapping layers of the non-coated portion 43 to ensure sufficient welding strength.

[0177] Preferably, the width D1 of the segmented piece 61' can be adjusted within the range of 1 to 8 mm. If D1 is less than 1 mm, when the segmented piece 61' is bent toward the core side, a region or space (gap) where the segmented pieces 61' do not overlap may occur, such that sufficient welding strength cannot be ensured. On the other hand, if D1 exceeds 8 mm, when the segmented piece 61 is bent, the non-coated portion 43 near the bending point may be torn by stress. Also, the height of the segmented piece 61' can be adjusted within the range of 2 to 10 mm. If D2 is less than 2 mm, when the segmented piece 61' is bent toward the core side, a region or space (gap) where the segmented pieces 61' do not overlap may occur, such that sufficient welding strength cannot be ensured. On the other hand, if D2 exceeds 10 mm, it is difficult to manufacture the electrode plate while maintaining the flatness of the non-coated portion 43 uniformly in the winding direction. Further, the separation pitch D3 of the segmented pieces 61' can be adjusted within the range of 0.05 to 1 mm. If D3 is less than 0.05 mm, when the segmented piece 61' is bent, the non-coated portion 43 near the bending point D4 may be torn by stress. On the other hand, if D3 exceeds 1 mm, when the segmented piece 61' is bent, a region or space (gap) where the segmented pieces 61' do not overlap with each other may occur, such that sufficient welding strength cannot be ensured.

[0178] A cutting portion 62 is interposed between two adjacent segmented pieces 61' in the winding direction X direction. The cutting portion 62 is a space formed by removing the non-coated portion 43. Preferably, the corner portion at the lower end of the cutting portion 62 may have a round shape (see partial enlargement). The round shape can relieve stress when the segmented piece 61' is bent.

[0179] Referring to FIGS. 13 and 14, the lower inner angle θ of the plurality of segmented pieces 61' can increase as it progresses from the core side to the outer peripheral side. As the radius of the electrode assembly 70 increases, the curvature increases. If the lower inner angle θ of the segmented piece 61' increases as the radius of the electrode assembly increases, when the segmented piece 61' is bent, the stress generated in the radial and circumferential directions can be relaxed. Also, when the lower inner angle θ increases, when the segmented piece 61' is bent, the area and the number of overlapping layers that overlap with the inner segmented piece 61' both increase, so that the welding strength can be uniformly ensured in the radial and circumferential directions, and the bent surface can be formed flat.

[0180] In one example, when the electrode plate 70 is used to manufacture an electrode assembly of a cylindrical cell with a form factor of 46800, when the diameter of the core (hollow) is 4 mm and the radius of the electrode assembly 70 increases from 4 mm to 22 mm, the inner angle of the segmented piece 61' can increase stepwise in the range of 60° to 85°.

[0181] In a modified example, the height of the outer peripheral non-coated portion B3 can decrease gradually or stepwise as in the first and second embodiments. Also, the segmented structure of the intermediate non-coated portion B2 can be extended to the outer peripheral non-coated portion B3 (see the dotted line). In this case, the outer peripheral non-coated portion B3 can also include a plurality of segmented pieces similar to the intermediate non-coated portion B2. In this case, the segmented pieces of the outer peripheral non-coated portion B3 may have a width and / or height and / or separation pitch larger than those of the intermediate non-coated portion B2. Alternatively, the segmented structure of the outer peripheral non-coated portion B3 can be substantially the same as the group of segmented pieces existing on the outermost side of the intermediate non-coated portion B2.

[0182] In a specific embodiment, when the electrode plate 70 is used to manufacture an electrode assembly of a cylindrical cell with a form factor of 46800, the width d of the core-side non-coated portion B1 B1can be 180 to 350 mm. The width of Group 1 can be 35 to 40% with respect to the width of the non-coated portion B1 on the core side. The width of Group 2 can be 130 to 150% with respect to the width of Group 1. The width of Group 3 can be 120 to 135% with respect to the width of Group 2. The width of Group 4 can be 85 to 90% with respect to the width of Group 3. The width of Group 5 can be 120 to 130% with respect to the width of Group 4. The width of Group 6 can be 100 to 120% with respect to the width of Group 5. The width of Group 7 can be 90 to 120% with respect to the width of Group 6. The width of Group 8 can be 115 to 130% with respect to the width of Group 7. The width d of the non-coated portion B3 on the outer peripheral side B3 can be the same as the width of the non-coated portion B1 on the core side, i.e., 180 to 350 mm.

[0183] The reason why the widths of Groups 1 to 8 do not show a constant increase or decrease pattern is that although the width of the segmented pieces gradually increases as it progresses from Group 1 to Group 8, the number of segmented pieces included in each group is limited to an integer. Therefore, in a specific segmented piece group, the number of segmented pieces can decrease. Accordingly, the width of the group can show an irregular change pattern as exemplified above as it progresses from the core side to the outer peripheral side.

[0184] That is, when the widths in the winding direction for each of three continuously adjacent segmented piece groups in the circumferential direction of the electrode assembly are W1, W2, and W3 respectively, it may include a combination of segmented piece groups where W3 / W2 is smaller than W2 / W1.

[0185] In the above specific example, Groups 4 to 6 correspond to this. The ratio of the width of Group 5 to Group 4 is 120 to 130%, and the ratio of the width of Group 6 to Group 5 is 100 to 120%, and its value is smaller than 120 to 130%.

[0186] FIG. 15 is a cross-sectional view of an electrode assembly according to an embodiment of the present invention cut along the Y-axis direction (winding axis direction).

[0187] Referring to FIG. 15, the non-coated portion 43a of the electrode plate includes a core-side non-coated portion B1 adjacent to the core of the electrode assembly 100, an outer-periphery-side non-coated portion B3 adjacent to the outer peripheral surface of the electrode assembly 100, and an intermediate non-coated portion B2 interposed between the core-side non-coated portion B1 and the outer-periphery-side non-coated portion B3.

[0188] The height of the core-side non-coated portion B1 is relatively smaller than the height of the intermediate non-coated portion B2. Also, the bending length of the non-coated portion 43a located innermost in the intermediate non-coated portion B2 is the same as or smaller than the radial length R of the core-side non-coated portion B1. The bending length H corresponds to the height of the non-coated portion 43a based on the point (h in FIG. 12, h in FIG. 14) where the non-coated portion 43a is bent.

[0189] Therefore, even if the intermediate non-coated portion B2 is bent, the bent portion does not block the cavity 102 of the core of the electrode assembly 100. When the cavity 102 is not blocked, there is no difficulty in the electrolyte injection process, and the efficiency of electrolyte injection is improved. Also, it is possible 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) by inserting a welding jig into the cavity 102.

[0190] The height of the outer-periphery-side non-coated portion B3 is relatively smaller than the height of the intermediate non-coated portion B2. Therefore, it is possible to prevent the beading portion of the battery can and the outer-periphery-side non-coated portion B3 from coming into contact with each other in the process of pressurizing the beading portion of the battery can near the outer-periphery-side non-coated portion B3.

[0191] In a modified example, the height of the outer-periphery-side non-coated portion B3 may decrease gradually or stepwise, different from what is shown in FIG. 15. Also, in FIG. 15, a part of the height of the intermediate non-coated portion B2 is the same as that of the outer periphery, but the height of the intermediate non-coated portion B2 may increase gradually or stepwise from the boundary between the core-side non-coated portion B1 and the intermediate non-coated portion B2 to the boundary between the intermediate non-coated portion B2 and the outer-periphery-side non-coated portion B3.

[0192] The lower non-coated portion 43b has the same structure as the upper non-coated portion 43a. In a variant, the lower non-coated portion 43b may have a conventional electrode plate structure or the electrode plate structure of other embodiments (variants).

[0193] The ends 101 of the upper non-coated portion 43a and the lower non-coated portion 43b can be bent from the outer peripheral side to the core side of the electrode assembly 100. At this time, the core-side non-coated portion B1 and the outer peripheral-side non-coated portion B3 are not substantially bent.

[0194] When the intermediate non-coated portion B2 includes a plurality of segmented pieces, it is possible to prevent the bending stress from being relaxed and the non-coated portion 43a near the bending point from being torn or abnormally deformed. Further, when the width and / or height and / or separation pitch of the segmented pieces are adjusted according to the numerical ranges of the above-described embodiments, the segmented pieces are stacked multiple times to such an extent that sufficient welding strength can be ensured while being bent toward the core side, and holes (gaps) are not formed in the bending surface (the surface viewed from the Y-axis).

[0195] FIG. 16 is a cross-sectional view of an electrode assembly according to another embodiment of the present invention taken along the Y-axis direction (the winding axis direction).

[0196] Referring to FIG. 16, the electrode assembly 110 has substantially the same remaining configuration as the electrode assembly 100 of FIG. 15, except that the height of the outer peripheral-side non-coated portion B3 is substantially the same as the outermost height of the intermediate non-coated portion B2. The outer peripheral-side non-coated portion B3 may include a plurality of segmented pieces.

[0197] In the electrode assembly 110, the height of the core-side non-coated portion B1 is relatively smaller than the height of the intermediate non-coated portion B2. Further, the bending length H of the non-coated portion located innermost in the intermediate non-coated portion B2 is the same as or smaller than the radial length R of the core-side non-coated portion B1.

[0198] Therefore, even if the intermediate non-coated portion B2 is bent, the bent portion does not block the cavity 112 of the core of the electrode assembly 110. When the cavity 112 is not blocked, there is no difficulty in the electrolyte injection process, and the efficiency of electrolyte injection is improved. In addition, it is possible 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) by inserting a welding jig from the cavity 112.

[0199] In a modified example, the structure in which the height of the intermediate non-coated portion B2 gradually or stepwise increases from the core side toward the outer peripheral side can be extended to the outer peripheral non-coated portion B3. In this case, the height of the non-coated portion 43a can gradually or stepwise increase from the boundary between the core-side non-coated portion B1 and the intermediate non-coated portion B2 to the outer surface of the electrode assembly 110 on the outer side.

[0200] The lower non-coated portion 43b has the same structure as the upper non-coated portion 43a. In a modified example, the lower non-coated portion 43b can have the structure of a conventional electrode plate or the electrode plate of other embodiments (modified examples).

[0201] The ends 111 of the upper non-coated portion 43a and the lower non-coated portion 43b can be bent from the outer peripheral side to the core side of the electrode assembly 110. At this time, the core-side non-coated portion B1 is not substantially bent.

[0202] When the intermediate non-coated portion B2 and the outer peripheral non-coated portion B3 include a plurality of segmented pieces, the bending stress can be relaxed to prevent the non-coated portions 43a and 43b near the bending point from being torn or abnormally deformed. Further, when the width and / or height and / or separation pitch of the segmented pieces are adjusted according to the numerical ranges of the above-described embodiments, the segmented pieces are overlapped multiple times to such an extent that sufficient welding strength can be ensured while being bent toward the core side, and no holes (gaps) are formed in the bending surface (the surface viewed from the Y axis).

[0203] FIG. 17 is a diagram schematically showing the configuration of a battery pack according to an embodiment of the present invention.

[0204] Referring to FIG. 17, a battery pack 800 according to an embodiment of the present invention includes an assembly in which cylindrical battery cells 10 are electrically connected and a pack housing 810 that houses the same. The cylindrical battery cell 10 is a battery cell according to the above-described embodiment. In the drawings, for the sake of illustration, illustration of components such as busbars, cooling units, and external terminals for electrical connection of the cylindrical battery cells 10 is omitted.

[0205] The battery pack 800 can be mounted on an automobile 900. The automobile 900 is an example and can be an electric vehicle, a hybrid vehicle, or a plug-in hybrid vehicle. The automobile 900 includes a four-wheel vehicle or a two-wheel vehicle.

[0206] FIG. 18 is a diagram for explaining an automobile including the battery pack of FIG. 17.

[0207] Referring to FIG. 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 power from the battery pack 800 according to an embodiment of the present invention.

[0208] FIGS. 19 to 25 are diagrams showing the manufacturing process of a cylindrical battery cell according to an embodiment of the present invention.

[0209] A method for manufacturing a cylindrical battery cell according to an embodiment of the present invention will be described. However, the content common to the cylindrical battery cell according to the above-described embodiment of the present invention replaces the above-described explanation.

[0210] First, referring to FIG. 19, an electrode assembly 100 is prepared. The electrode assembly 100 has a jelly roll type structure in which a sheet-like first electrode plate 140, a second electrode plate 160, and a separator 150 interposed therebetween are wound in one direction. The first electrode plate 140 includes a first non-coated portion 110 having no active material layer coated on the long end portion. The first non-coated portion 110 and the second non-coated portion 120 are exposed outside the separator while forming a plurality of winding turns with respect to the center of the electrode assembly 100 and are used as electrode tabs.

[0211] Next, a current collector plate 300 is coupled to the first non-coated portion 110 of the electrode assembly 100.

[0212] Thereafter, referring to FIG. 20, a battery can 200 having an open portion 220 for housing the electrode assembly 100 and a partial closing portion 210 on the opposite side thereof is prepared, and the battery can 200 is electrically connected to the second electrode plate 160.

[0213] Next, a cell terminal 400 is coupled to the battery can 200 through a riveting process from a through hole 211 in the closing portion 210 of the battery can 200.

[0214] Next, referring to FIG. 21, the insulator 600 is coupled to the inner surface of the closing portion 210 of the battery can 200 in a state where the battery can 200 is arranged such that the cell terminal 400 is positioned downward. According to one aspect, at least one protrusion 610 is formed on the outer peripheral surface of the insulator 600, and the insulator 600 can be coupled to the battery can 200 by interference fit. Desirably, a plurality of protrusions 610 are provided, and the plurality of protrusions 610 are formed at preset intervals on the outer peripheral surface of the insulator 600 and can be pressed by interference fit. According to another aspect, in the insulator 600, a heat welding layer is formed on the surface facing the inner surface of the closing portion 210 of the battery can 200, and the insulator 600 can be fixed to the battery can 200 by heat welding. According to still another aspect, an adhesive layer is formed on the upper surface of the insulator 600 that contacts the battery can 200, and the insulator 600 can be fixed to the battery can 200 by adhesion. According to yet another aspect, the insulator 600 can be fixed to the battery can 200 by a double-sided tape.

[0215] Desirably, the electrolyte can be injected in a state where the battery can 200 is erected so that the cell terminal 400 faces the direction of gravity. At least one through hole 620 is provided on the upper surface of the insulator 600 that is connected from the outer peripheral surface of the insulator 600, and the electrolyte can move from the through hole 620 into the interior of the electrode assembly 100. Desirably, a plurality of through holes 620 are formed, and the plurality of through holes 620 can be separated at preset intervals. Desirably, a plurality of through holes 620 can be arranged on a single straight line extending from the central portion of the insulator 600 toward the outer peripheral surface of the insulator 600. Desirably, a plurality of through holes 620 can be arranged for each straight line with respect to a plurality of straight lines arranged radially from the central portion of the insulator 600 toward the outer peripheral surface of the insulator 600.

[0216] Next, referring to 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.

[0217] Next, referring to FIG. 23, the lower current collector plate 700 is joined to the second non-coated portion 120 of the second electrode plate 160 by welding. Depending on the process design, the welding of the lower current collector plate 700 can be performed before the electrode assembly 100 is inserted into the battery can 200. For the specific descriptions of the second electrode plate 160 and the lower current collector plate 700, the foregoing descriptions are substituted.

[0218] Next, referring to FIG. 24, a beading portion 240 is formed on the battery can 200. The edge of the lower current collector plate 700 is welded in a state of being mounted on a flat surface adjacent to the crimping portion 250 of the beading portion 240. For the specific description of the beading portion 240, the foregoing descriptions are substituted.

[0219] Next, referring to FIG. 25, a crimping portion 250 is formed on the battery can 200. When forming the crimping portion 250, the peripheral edge of the cap plate 230 is supported by the beading portion 240 via the sealing gasket 260, and the upper end of the battery can 200 is bent inward to press the sealing gasket 260 to fix the cap plate 230. For the specific description of the crimping portion 250, the foregoing descriptions are substituted.

[0220] 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 later inserted into the battery can, the insulator can be joined to the jelly roll type electrode assembly at an accurate position, thereby improving the insulation and preventing the occurrence of defects.

[0221] As described above, the present invention has been described with reference to the limited embodiments and drawings. However, the present invention is not limited thereto, and it is needless to say that various modifications and variations can be made within the equivalent scope of the technical idea and the claims of the present invention by those having ordinary knowledge in the technical field to which the present invention pertains.

Description of Reference Numerals

[0222] 10 Battery cell 21 Beading portion 42 Active material layer 43 Non-coated part 44 Insulating coating layer 52 Bottom part 54 Rivet gasket 60 Electrode plate 61, 61’ Section pieces 62 Cutting part 100, 110 Electrode assembly 110 First non-coated part 120 Second non-coated part 140 First electrode plate 150 Separation membrane 160 Second electrode plate 200 Battery can 210 Closing part 211 Through hole 220 Open part 230 Cap plate 240 Beading part 250 Crimping part 260 Sealing gasket 300 Current collector plate 400 Cell terminal 410 Terminal insertion part 500 Insulating tape 600 Insulator 610 Protrusion part 620 Through hole 630 Protrusion housing part 700 Lower current collector plate 800 Battery pack 810 Pack housing 900 Automobile

Claims

1. An electrode assembly having a structure in which a first electrode plate, a second electrode plate, and a separator interposed therebetween are wound in one direction, A battery can having an open portion provided on one side so as to house the electrode assembly and a partial closing portion provided on the opposite side thereof, and 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 plate through a through hole in the closing portion of the battery can, An insulator provided with a central hole for exposing the lower portion of the cell terminal and interposed between the battery can and the current collector plate, A battery cell including the above.

2. The 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.

3. The insulator, When the electrode assembly is housed in the battery can, the insulator includes a protrusion provided on an outer peripheral surface of the insulator so as to press an inner surface of the battery can. The battery cell according to claim 1 or 2.

4. A plurality of the protrusions are provided, The battery cell according to claim 3, wherein the plurality of protrusions are provided at preset intervals on an outer peripheral surface of the insulator.

5. The battery cell according to claim 4, wherein the plurality of protrusions are spaced apart at equal intervals along a circumferential direction on an outer peripheral surface of the insulator.

6. When the electrode assembly is housed in a battery can, the insulator has an adhesive layer formed on an upper surface of the insulator that contacts the battery can so as to be fixed to the battery can by adhesion. The battery cell according to claim 1 or 2.

7. The insulator, The battery cell according to claim 1 or 2, further comprising a through hole formed in a region between an outer peripheral surface and the central hole.

8. The battery cell according to claim 3, wherein a distance from a center of the insulator to an end of the protrusion is greater than a radius of the electrode assembly.

9. The battery cell according to claim 3, wherein a distance from a center of the insulator to a region on the outer peripheral surface of the insulator where the protrusion is not formed is the same as or greater than a radius of the electrode assembly.

10. The battery cell according to claim 3, characterized in that the distance from the center of the insulator to the end of the protrusion is greater than the inner diameter of the battery can.

11. The battery cell according to claim 10, characterized in that the protrusion is configured to be elastically pressed inward of the insulator by the inner surface of the battery can.

12. The insulator The battery cell according to claim 1 or 2, characterized in that it has a thickness corresponding to the distance between the inner surface of the closed portion of the battery can and the current collector plate.

13. The insulator The battery cell according to claim 3, characterized in that it includes a protrusion receiving portion spaced in a direction from a position corresponding to the protrusion toward the center of the insulator.

14. The outer portion of the protrusion receiving portion The battery cell according to claim 13, characterized in that it has a form bulging in a direction toward the protrusion.

15. The protrusion receiving portion The battery cell according to claim 13, characterized in that it has a length corresponding to the distance from one end to the other end in the circumferential direction of the insulator at the protrusion.

16. The battery cell according to claim 14, characterized in that the radius of curvature of the outer portion of the protrusion receiving portion is smaller than the radius of curvature of the protrusion.

17. The battery cell according to claim 1 or 2, further comprising a cap plate configured to seal the open portion of the battery can.

18. The battery cell according to claim 17, characterized in that the cap plate is insulated from the battery can and has no polarity.

19. A battery pack including at least one battery cell according to claim 1 or 2.

20. An automobile including at least one battery pack according to claim 19.

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