Electrode assemblies, cylindrical battery cells, battery packs containing them, and automobiles

Abstract

The present invention provides an electrode assembly having an improved structure, a cylindrical battery cell using the electrode assembly, a battery pack manufactured using the cylindrical battery cell, and an automobile including the same. [Solution] The present invention discloses an electrode assembly, a cylindrical battery cell, a battery pack including the same, and an automobile. The electrode assembly is a jelly roll type electrode assembly having a structure in which a sheet-like first electrode current collector and a second electrode current collector and a separation membrane interposed between the first electrode current collector and the second electrode current collector are wound in one direction, wherein the first electrode current collector includes a first plain portion at the long side end where the active material layer is not coated, the first plain portion is exposed to the outside of the separation membrane while forming a plurality of winding turns with respect to the center of the electrode assembly, and is used as an electrode tab itself, and includes an insulating member that covers the exposed curved surface of the first plain portion located at the outermost winding turn that is exposed on the outer circumferential surface of the electrode assembly among the plurality of winding turns.

Description

Technical Field

[0001] This application claims priority based on Korean Patent Application No. 10-2021-0130390 filed on September 30, 2021, Korean Patent Application No. 10-2021-0177062 filed on December 10, 2021, and Korean Patent Application No. 10-2022-0089232 filed on July 19, 2022, and all the contents disclosed in the specifications and drawings of those applications are incorporated into this application.

[0002] The present invention relates to an electrode assembly, a cylindrical battery cell, a battery pack including the same, and a vehicle, and more particularly, to an electrode assembly, a cylindrical battery cell, a battery pack including the same, and a vehicle capable of increasing the capacity of a battery cell by reducing the thickness of an insulating member.

Background Art

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

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

[0005] Currently, secondary batteries such as lithium-ion batteries, lithium polymer batteries, nickel cadmium batteries, nickel metal hydride batteries, and nickel zinc batteries are widely used. 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, depending on the charge / discharge capacity required for the battery pack, a plurality of battery cells may be connected in parallel to form a battery pack. Therefore, the number and electrical connection form of the battery cells included in the battery pack can be variably set according to at least one of the required output voltage and charge / discharge capacity.

[0007] On the other 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 this is wound to form a jelly-roll type 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 type electrode assembly.

[0009] On the other hand, in recent years, with the application of cylindrical battery cells to electric vehicles, the form factor of cylindrical battery cells has been increasing. That is, the diameter and height of cylindrical battery cells are increasing compared to conventional cylindrical battery cells having form factors such as 18650 and 21700. The increase in the form factor brings an increase in energy density, an increase in safety against thermal runaway, and an improvement in cooling efficiency.

[0010] The energy density of a cylindrical battery cell can further increase when the unnecessary space inside the battery can is minimized along with the increase in the form factor. Therefore, the components used for electrical insulation between the electrode assembly and the battery can need to be optimally designed to ensure electrical insulation and increase the capacity of the battery cell. Summary of the Invention Problems to be Solved by the Invention

[0011] The present invention was conceived against the background of the prior art described above, and aims to provide an electrode assembly, a cylindrical battery cell, a battery pack including the same, and an automobile, which can improve the insulating structure of the electrode assembly and reduce the thickness of the insulating member, thereby preventing the insulating member from unnecessarily occupying space between the side surface of the electrode assembly and the battery can.

[0012] Another objective of the present invention is to provide an electrode assembly, a cylindrical battery cell, a battery pack including the same, and an automobile, in which the size of the electrode assembly can be increased by reducing the thickness of the insulating member, thereby increasing the capacity of the battery cell.

[0013] Furthermore, another objective of the present invention is to provide an electrode assembly, a cylindrical battery cell, a battery pack including the same, and an automobile that can minimize the space between the battery can and the electrode assembly and solve problems caused by vibration.

[0014] Furthermore, another objective of the present invention is to provide an electrode assembly, a cylindrical battery cell, a battery pack including the same, and an automobile, in which the degree of design freedom and injection performance are improved when an insulating plate is provided on the upper side of the insulating member.

[0015] Furthermore, the present invention aims to provide a battery pack manufactured using cylindrical battery cells having an improved structure, and an automobile including the same.

[0016] However, the technical problems that this invention aims to solve are not limited to those described above, and other problems will be clearly understood by an ordinary person from the description of the invention below. [Means for solving the problem]

[0017] To achieve the above objectives, an electrode assembly according to one aspect of the present invention is a jelly roll type electrode assembly having a structure in which a sheet-like first electrode current collector and a second electrode current collector and a separation membrane interposed between the first electrode current collector and the second electrode current collector are wound in one direction, wherein the first electrode current collector includes a first plain portion at the long end where the active material layer is not coated, the first plain portion is exposed to the outside of the separation membrane while forming a plurality of winding turns with respect to the center of the electrode assembly and is used as an electrode tab, and the electrode assembly includes an insulating member that covers the exposed curved surface of the first plain portion located at the outermost winding turn among the plurality of winding turns that is exposed on the outer circumferential surface of the electrode assembly.

[0018] Preferably, the insulating member may be an insulating tape having an adhesive layer formed on the surface opposite the first plain portion.

[0019] In one embodiment, the insulating tape may be a single-sided tape in which an adhesive layer is formed on only one side.

[0020] In other embodiments, the insulating member may be composed of a heat-shrinkable tube that shrinks when heat is applied.

[0021] In yet another embodiment, the insulating member may be formed wider than the width of the exposed curved surface (length in the winding axis direction) so as to cover the exposed curved surface of the first plain portion.

[0022] Preferably, the thickness of the insulating tape may be 10 μm or more and 50 μm or less.

[0023] In yet another embodiment, the insulating tape may be provided so as to cover the electrode assembly in one or more layers.

[0024] In yet another embodiment, the insulating tape may be manufactured from a material that prevents thermal deformation when the electrode assembly generates heat.

[0025] Preferably, the insulating tape may be manufactured from polyimide (PI), polyethylene terephthalate (PET), or polypropylene (PP).

[0026] In one embodiment, the insulating tape may contain polyimide in the portion that covers the exposed curved surface of the first plain portion.

[0027] In other embodiments, the insulating tape may contain polyimide in the portion covering the exposed curved surface of the first plain portion, and polyethylene terephthalate in the portion covering the separation membrane adjacent to the exposed curved surface.

[0028] In yet another embodiment, at least a portion of the first blank section may be divided into a plurality of segments along the winding direction of the electrode assembly.

[0029] Preferably, the plurality of segments can be bent along the radial direction of the electrode assembly.

[0030] Preferably, the plurality of segments may overlap multiple times along the radial direction of the electrode assembly.

[0031] In yet another embodiment, the insulating tape may be attached to at least a portion of the outer circumferential surface of the electrode assembly and at least a portion of the upper surface of the electrode assembly.

[0032] Preferably, the insulating tape may include a first portion that is attached to the outer circumferential surface of the electrode assembly, and a second portion that extends from the first portion, is bent from the first portion, and is attached to the upper surface of the electrode assembly.

[0033] In one embodiment, the first portion may be provided to cover the outermost exposed curved surfaces of the folded segments of the first plain portion, and at least a portion of the separation membrane adjacent thereto.

[0034] In other embodiments, the first portion may have a size such that the portion covering the outermost exposed curved surface of the plurality of subsections of the first plain portion is smaller than or equal to the size of the portion covering the separation membrane adjacent to the exposed curved surface.

[0035] In other embodiments, the second portion may cover the upper surfaces of the folded segments of the first plain portion.

[0036] Preferably, the first portion may be made larger than the second portion.

[0037] In other embodiments, at least one notch may be formed in the second portion.

[0038] In yet another embodiment, the lower end of the notch may be positioned higher than the bent surface of the first plain portion.

[0039] To achieve the above objectives, a cylindrical battery cell according to another aspect of the present invention is a jelly roll type electrode assembly having a structure in which a sheet-like first electrode current collector and a second electrode current collector and a separation membrane interposed between the first electrode current collector and the second electrode current collector are wound in one direction, wherein the first electrode current collector includes a first plain portion at the long end of the long side where the active material layer is not coated, and the first plain portion is exposed to the outside of the separation membrane while forming a plurality of winding turns with respect to the center of the electrode assembly and is used as an electrode tab; a cylindrical battery can in which the electrode assembly is housed and electrically connected to the second electrode current collector; a current collector plate electrically connected to the first electrode current collector; a cell terminal connected to the current collector plate; and an insulating member covering the exposed curved surface of the first plain portion located at the outermost winding turn exposed on the outer circumferential surface of the electrode assembly among the plurality of winding turns.

[0040] Preferably, the diameter of the battery can is formed to be larger than the diameter of the electrode assembly, a predetermined gap is provided between the battery can and the electrode assembly, and the insulating member may be interposed in the gap.

[0041] Preferably, the insulating member may be an insulating tape having an adhesive layer formed on the surface opposite the first plain portion.

[0042] Preferably, at least a portion of the first blank section can be divided into a plurality of segments along the winding direction of the electrode assembly.

[0043] Preferably, the plurality of segments can be bent along the radial direction of the electrode assembly.

[0044] Preferably, the plurality of segments may overlap multiple times along the radial direction of the electrode assembly.

[0045] In one embodiment, the insulating tape may include a first portion that is attached to the outer circumferential surface of the electrode assembly, and a second portion that extends from the first portion, is bent from the first portion, and is attached to the upper surface of the current collector plate that is coupled to the electrode assembly.

[0046] Preferably, the first portion may be provided to cover the outermost exposed curved surfaces of the folded segments of the first plain portion, and at least a portion of the adjacent separation membrane.

[0047] Preferably, the second portion may be provided to cover a current collector plate joined to the upper portion of a plurality of folded segments of the first plain portion.

[0048] Preferably, the insulating tape can be bent from the outermost exposed curved end of the multiple bent segments of the first plain section and joined to the upper side of the current collector plate.

[0049] Preferably, a welded portion is formed on the current collector plate by welding the first plain portion, and the second portion can be joined to the upper side of the current collector plate, spaced apart from the outer edge of the welded portion so as not to interfere with the welded portion.

[0050] In other embodiments, the insulating tape may include a first portion that is attached to the outer circumferential surface of the electrode assembly, and a second portion that extends from the first portion, is bent from the first portion, and is attached to the bent surfaces of the plurality of segments of the first plain portion.

[0051] Preferably, the current collector plate may be positioned above the second portion of the insulating tape.

[0052] In yet another embodiment, the battery can may further include a cap plate configured to seal the open portion of the battery can, with a closed portion and an open portion formed opposite each other.

[0053] Preferably, the cap plate may be provided separately from the electrode assembly and be nonpolar.

[0054] In yet another embodiment, a through hole is formed in the closing portion, and the cell terminal can be connected to the through hole.

[0055] In yet another embodiment, an insulating plate interposed between the closing portion and the current collector plate may be further included.

[0056] Preferably, the insulating board may include an insulating polymer material.

[0057] In yet another embodiment, the insulating plate may be made of an elastic material.

[0058] In yet another embodiment, the insulating plate may have a central hole in its center having a predetermined diameter.

[0059] Preferably, the cell terminals are provided with terminal insertion portions, and these terminal insertion portions can be inserted into the battery can through the through holes.

[0060] Preferably, the cell terminal can be fixed in the through hole with the lower peripheral edge of the terminal insertion portion riveted toward the inner surface of the upper end of the battery can.

[0061] Preferably, the diameter of the central hole in the insulating plate may be larger than or equal to the diameter of the terminal insertion portion.

[0062] Preferably, the terminal insertion portion of the cell terminal may penetrate the central hole of the insulating plate.

[0063] Preferably, the terminal insertion portion of the cell terminal can penetrate the central hole of the insulating plate and be electrically connected to the current collector plate.

[0064] In yet another embodiment, the cylindrical battery cell according to the present invention may include a sealing gasket interposed between the periphery of the cap plate and the opening of the battery can. The battery can may also include a beading portion pressed inward into the battery can in a region adjacent to the opening. The battery can may also include a crimping portion that extends inward and is bent to wrap around and secure the periphery of the cap plate together with the sealing gasket.

[0065] Preferably, the crimping portion may be formed on the lower part of the battery can (i.e., on the opposite side of the closing portion) with respect to the arrangement of the battery can.

[0066] Preferably, the cap plate may include a venting notch that ruptures when the internal pressure of the battery can exceeds a critical value.

[0067] In one embodiment, the venting notches are formed on both sides of the cap plate and may be formed on the surface of the cap plate in at least one of a continuous circular pattern, a discontinuous circular pattern, and a linear pattern.

[0068] In another embodiment, the venting notch is formed at the bottom of the battery can with respect to the arrangement of the battery can, and when the venting notch ruptures, the gas inside the battery can is released from the bottom of the battery can.

[0069] In yet another embodiment, the electrode assembly may further include a lower current collector plate coupled to the lower part of the electrode assembly.

[0070] Preferably, the second electrode current collector includes a second plain portion at its long edge that is not coated with an active material layer, the second plain portion being exposed to the outside of the separator film while forming a plurality of winding turns with respect to the center of the electrode assembly, and can itself be used as an electrode tab.

[0071] Preferably, the lower current collector plate is made of a conductive metallic material and can be electrically connected to the second blank portion of the second electrode current collector. At least a portion of the second blank portion can be divided into a plurality of segments. The plurality of segments can also be folded along the radial direction of the electrode assembly and overlap in multiple layers.

[0072] Preferably, at least a portion of the edge of the lower current collector plate may be electrically connected to the beading portion of the battery can. More preferably, at least a portion of the edge of the lower current collector plate may be electrically connected through the lower surface of the beading portion adjacent to the crimping portion.

[0073] Preferably, the lower current collector plate may be joined to the curved surface of the second plain portion by welding, with at least a portion of the other parts excluding the part electrically connected to the beading portion.

[0074] Preferably, the insulating member may have a thickness corresponding to the distance between the current collector plate and the inner surface of the upper end of the battery can.

[0075] Preferably, the thickness of the insulating member may be 100 to 500 μm.

[0076] The above problems can also be solved by a battery pack including at least one of the cylindrical battery cells described above, and by an automobile including at least one of the battery packs. [Effects of the Invention]

[0077] According to one aspect of the present invention, the insulating structure of the electrode assembly can be improved to reduce the thickness of the insulating member, thereby preventing the insulating member from unnecessarily occupying space between the side surface of the electrode assembly and the battery can.

[0078] Furthermore, according to one aspect of the present invention, the size of the electrode assembly increases by reducing the thickness of the insulating member, thereby enabling an increase in the capacity of the battery cell.

[0079] Furthermore, according to one aspect of the present invention, the space between the battery can and the electrode assembly can be minimized to solve the problem caused by vibration.

[0080] Furthermore, according to one aspect of the present invention, when an insulating plate is provided on the upper side of the insulating member, the degree of design freedom is increased and injection performance can also be improved.

[0081] Furthermore, according to one aspect of the present invention, a battery pack with improved capacity can be provided by using cylindrical battery cells having an improved structure, and an automobile including the same.

[0082] The following drawings accompanying this specification illustrate preferred embodiments of the invention and, together with the detailed description of the invention, are intended to further illustrate the technical idea of ​​the invention; therefore, the invention shall not be construed as being limited solely to what is shown in the drawings. [Brief explanation of the drawing]

[0083] [Figure 1] This is a perspective view of a cylindrical battery cell according to one embodiment of the present invention. [Figure 2] Figure 1 is a cross-sectional perspective view showing the central part of a cylindrical battery cell. [Figure 3] This is a cross-sectional view of a cylindrical battery cell according to one embodiment of the present invention. [Figure 4] This diagram shows a battery casing in a cylindrical battery cell according to one embodiment of the present invention. [Figure 5] This figure shows an insulating tape attached to the side surface of an electrode assembly in a cylindrical battery cell according to one embodiment of the present invention. [Figure 6] Figure 5 shows the process, indicated by the arrows, of how the insulating tape attached to the side of the electrode assembly is folded and then attached to the top surface of the current collector. [Figure 7] This figure shows how insulating tape is applied to the side surface of the electrode assembly and the top surface of the current collector through the process shown in Figure 6. [Figure 8] This figure shows an example of a cylindrical battery cell according to another embodiment of Figure 5, in which insulating tape is attached to the side surface of the electrode assembly. [Figure 9] Figure 3 is a cross-sectional view of another embodiment of the cylindrical battery cell. [Figure 10] This figure illustrates a cylindrical secondary battery according to another embodiment of the present invention. [Figure 11] This figure shows the current collector plate and welded portion in a cylindrical battery cell according to one embodiment of the present invention. [Figure 12] This is a plan view showing the structure of an electrode current collector according to one embodiment of the present invention. [Figure 13] Figure 12 shows the definitions of the width, height, and spacing pitch of the segment. [Figure 14] This is a plan view showing the structure of an electrode current collector according to another embodiment of the present invention. [Figure 15] Figure 14 shows the definitions of the width, height, and spacing pitch of the segment. [Figure 16] This is a cross-sectional view of an electrode assembly according to one embodiment of the present invention, cut along the Y-axis direction (winding axis direction). [Figure 17] This is a cross-sectional view of an electrode assembly according to another embodiment of the present invention, cut along the Y-axis direction (winding axis direction). [Figure 18] This diagram schematically shows the configuration of a battery pack according to one embodiment of the present invention. [Figure 19]Figure 18 is a diagram illustrating an automobile that includes a battery pack. [Modes for carrying out the invention]

[0084] Preferred embodiments of the present invention will be described in detail below with reference to the attached drawings. Prior to this, terms and words used in this specification and in the claims shall not be interpreted in their usual and dictionary sense, but rather in a sense and concept corresponding to the technical idea of ​​the present invention, in accordance with the principle that the inventor himself may appropriately define the concept of terms in order to best describe the invention.

[0085] Therefore, it should be understood that the embodiments described herein and the configurations shown in the drawings represent only one of the most preferred embodiments of the present invention and do not represent the entire technical concept of the invention, and that there are various equivalents and modifications that can be substituted therein at the time of filing this application.

[0086] Furthermore, to aid in understanding the invention, the accompanying drawings are not shown to actual scale, and the dimensions of some components may be exaggerated. Also, the same reference numerals may be used for the same components in different embodiments.

[0087] Figure 1 is a perspective view of a cylindrical battery cell according to one embodiment of the present invention; Figure 2 is a cross-sectional perspective view showing the central part of the cylindrical battery cell of Figure 1; Figure 3 is a cross-sectional view of a cylindrical battery cell according to one embodiment of the present invention; Figure 4 is a diagram showing the battery casing in a cylindrical battery cell according to one embodiment of the present invention; Figure 5 is a diagram showing how insulating tape is attached to the side surface of the electrode assembly in a cylindrical battery cell according to one embodiment of the present invention; Figure 6 is a diagram showing the process of folding the insulating tape attached to the side surface of the electrode assembly in Figure 5 and attaching it to the upper surface of the current collector, along the arrows; Figure 7 is a diagram showing how insulating tape is attached to the side surface of the electrode assembly and the upper surface of the current collector by the process in Figure 6; Figure 8 is a diagram showing insulating tape attached to the side surface of the electrode assembly in a cylindrical battery cell according to another embodiment of Figure 5. Figure 10 is a diagram illustrating the configuration, Figure 9 is a cross-sectional view of another embodiment of the cylindrical battery cell in Figure 3, Figure 11 is a diagram showing the current collector plate and welded part in a cylindrical battery cell according to one embodiment of the present invention, Figure 12 is a plan view showing the structure of the electrode current collector according to one embodiment of the present invention, Figure 13 is a diagram showing the definitions of the width, height and separation pitch of the segment in Figure 12, Figure 14 is a plan view showing the structure of the electrode current collector according to another embodiment of the present invention, Figure 15 is a diagram showing the definitions of the width, height and separation pitch of the segment in Figure 14, Figure 16 is a cross-sectional view of the electrode assembly according to one embodiment of the present invention cut along the Y-axis direction (winding axis direction), and Figure 17 is a cross-sectional view of the electrode assembly according to another embodiment of the present invention cut along the Y-axis direction (winding axis direction).

[0088] First, an electrode assembly 100 according to one embodiment of the present invention will be described. The electrode assembly 100 is a jelly roll type electrode assembly 100 having a structure in which a sheet-shaped first electrode current collector and a second electrode current collector and a separation membrane interposed between them are wound in one direction.

[0089] Referring to Figure 3, the first electrode current collector includes a first blank portion 110 on its long side end where the active material layer is not coated. The second electrode current collector may also include a second blank portion 120 on its long side end where the active material layer is not coated. In other words, at least one of the first electrode current collector and the second electrode current collector may include a blank portion on its long side end in the winding direction where the active material is not coated.

[0090] Here, the first blank portion 110 is exposed to the outside of the separation membrane while forming multiple winding turns with respect to the center of the electrode assembly 100, and is used as an electrode tab itself.

[0091] Preferably, the electrode assembly 100 includes an insulating member 500 that covers the exposed curved surface 111 of the first plain portion 110 located in the outermost winding turn that is exposed on the outer surface of the electrode assembly 100 among a plurality of winding turns.

[0092] The insulating member 500 may be an insulating tape 510 with an adhesive layer formed on the surface opposite the first blank portion 110. That is, the first blank portion 110 can be electrically insulated by attaching the insulating tape 510 to it.

[0093] According to the inventors' research, in order to insulate the first blank portion 110, it is conceivable to use an insulating cap that covers both the upper and side surfaces of the electrode assembly 100. That is, the insulating cap can be provided so as to cover both the side surfaces of the electrode assembly 100 and the upper surface of the current collector plate 300.

[0094] However, in the case of an insulating cap that covers both the top and sides of the electrode assembly 100, while it is advantageous in terms of simplifying assembly, when the insulating cap is manufactured by injection molding, it is difficult to manufacture it below a certain size due to the limitations of injection molding. As a result, the insulating cap occupies a large volume inside the battery can 200, which has the limitation of increasing the size of the electrode assembly 100.

[0095] In reality, even when formed thinly, such injection-molded objects have a thickness of approximately 0.20 to 0.30 mm. Furthermore, a disadvantage is that the overall battery cell capacity cannot be increased without increasing the size of the electrode assembly 100. In addition, while the electrode assembly 100 is fixed in the parts of the battery can 200 where insulating caps are placed, a gap is created between the battery can 200 and the electrode assembly 100 in the parts without insulating caps, which may cause problems due to vibration.

[0096] An electrode assembly 100 according to one embodiment of the present invention includes an insulating tape 510 instead of an insulating cap to overcome the limitations of an insulating cap. This reduces the volume occupied by the insulating member 500 inside the battery can 200, thereby increasing the size of the electrode assembly 100 and consequently increasing the capacity of the battery cell. However, this description does not preclude the use of an insulating cap in the cylindrical battery cell 10 of the present invention.

[0097] In one embodiment, the insulating tape 510 may be a single-sided tape in which an adhesive layer is formed on only one side.

[0098] Alternatively, the insulating member 500 may be made of a heat-shrinkable tube that shrinks when heat is applied. That is, after covering the electrode assembly 100 with the heat-shrinkable tube, when heat is applied, the heat-shrinkable tube shrinks and adheres tightly to the electrode assembly 100. Here, the heat-shrinkable tube can be made from a variety of insulating materials.

[0099] The insulating member 500 may be formed wider than the width of the exposed curved surface 111 so as to cover the exposed curved surface 111 of the first plain portion 110. When the first plain portion 110 is wound up, the exposed curved surface 111 is formed in the outermost winding turn, but the insulating member 500 is formed wider than the width of the exposed curved surface 111 of the first plain portion 110 so as to cover the first plain portion 110. The insulating member 500 may have a thickness corresponding to the distance between the current collector plate 300 and the inner surface of the upper end of the battery can 200, for example the insulating member 500 may have a thickness of 100 to 500 μm.

[0100] The insulating member 500 may be formed wider than the width of the exposed surface so as to cover the exposed surface of the first plain portion 110. The first plain portion 110 is bent to form the exposed curved surface 111. The insulating member 500 is formed wider than the width of the exposed curved surface 111 of the first plain portion 110 so as to cover the exposed curved surface 111 of the first plain portion 110. The thickness of the insulating tape 510 is not particularly limited, but it may have a thickness of 10 μm or more and 50 μm or less.

[0101] In other embodiments, the insulating tape 510 may be provided in a single layer to cover the electrode assembly 100 so as to reduce the space occupied by the insulating member 500 between the battery can 200 and the electrode assembly 100, but is not limited to this, and the electrode assembly 100 may be covered with one or more layers from the standpoint of preventing short circuits.

[0102] Since the insulating tape 510 is attached to the electrode assembly 100, it is necessary to prevent thermal deformation caused by heat generated from the electrode assembly 100. Therefore, the insulating tape 510 can be manufactured from a variety of materials with high thermal deformation temperatures so as to prevent thermal deformation when the electrode assembly 100 generates heat.

[0103] For example, the insulating tape 510 may be manufactured from polyimide (PI), polyethylene terephthalate (PET), or polypropylene (PP). However, the material of the insulating tape 510 is not limited to the above materials.

[0104] Here, the insulating tape 510 may be provided so as to cover the exposed curved surface 111 of the first plain portion 110, and the insulating tape 510 made from polyimide may be provided. In this case, the insulating tape 510 may be attached to the electrode assembly 100 using only polyimide with a high thermal distortion temperature.

[0105] However, in the case of polyimide, although its thermal distortion temperature is high, it is expensive. Therefore, the exposed curved surface 111 of the first plain section 110, which generates a lot of heat, can be covered with insulating tape 510 made from polyimide, while the exposed curved surface 111 of the separation membrane adjacent to the exposed curved surface 111 of the first plain section 110, which does not generate a lot of heat, can be covered with insulating tape 510 made from polyethylene terephthalate, which is relatively cheaper than polyimide. For example, the first section 511 and the second section 512 in Figure 3 can be covered with insulating tape 510 made from polyimide, and section P in Figure 3 can be covered with insulating tape 510 made from polyethylene terephthalate. However, this is just one example and is not limited to this.

[0106] On the other hand, at least a portion of the first blank section 110 can be divided into a plurality of sub-sections 61 (see Figure 12) along the winding direction of the electrode assembly 100. Here, the plurality of sub-sections 61 can be bent, for example, toward the core along the radial direction of the electrode assembly 100.

[0107] Furthermore, the multiple sections 61 may have a structure in which they overlap in multiple layers along the radial direction of the electrode assembly 100. For example, the multiple sections 61 may be notched with a laser. The sections 61 can be formed by known metal foil cutting processes such as ultrasonic cutting or punching. The structure of the sections 61 will be described in more detail later.

[0108] To prevent damage to the active material layer during the bending process of the first blank section 110, it is desirable to provide a predetermined gap between the lower end of the cutting line between the segmented sections 61 and the active material layer. This is because stress is concentrated near the lower end of the cutting line when the first blank section 110 is bent. It is also because it becomes difficult to form a pattern during laser cutting. The gap is preferably 0.2 to 4 mm. If the gap is adjusted to the above numerical range, it is possible to prevent damage to the active material layer near the lower end of the cutting line due to the stress generated during the bending process of the first blank section 110. In addition, the gap can prevent damage to the active material layer due to tolerances during notching or cutting of the segmented sections 61.

[0109] As described above, the bending direction of the first blank portion 110 may be, for example, towards the winding center of the electrode assembly 100. When the first blank portion 110 has such a bent shape, the space occupied by the first blank portion 110 is reduced, which can improve energy density. In addition, the increased bonding area between the first blank portion 110 and the current collector plate 300 can provide the effects of further improvement in bonding strength and further reduction in resistance.

[0110] Although the folding and overlapping of the first plain section 110 have been described above, it goes without saying that the same structure as that of the first plain section 110 can also be applied to the second plain section 120.

[0111] The insulating tape 510 can be attached to the electrode assembly 100 in a variety of ways. For example, the insulating tape 510 can be attached to at least a portion of the outer circumferential surface of the electrode assembly 100 and at least a portion of the upper surface of the electrode assembly 100.

[0112] In another embodiment, when the current collector plate 300 is attached to the upper surface of the electrode assembly 100, the insulating tape 510 is attached to at least a portion of the outer circumferential surface of the electrode assembly 100 and at least a portion of the upper surface of the current collector plate 300. Figure 3 shows an embodiment in which the current collector plate 300 is attached to the upper surface of the electrode assembly 100 and the insulating tape 510 is attached to the upper surface of the current collector plate 300, while Figure 9 shows an embodiment in which the insulating tape 510 is directly attached to the upper surface of the electrode assembly 100.

[0113] Referring to Figure 5, the insulating tape 510 covers the entire outer surface of the electrode assembly 100 and protrudes above the current collector plate 300, higher than the sides of the electrode assembly 100. That is, the insulating tape 510 may be configured to include a first portion 511 that is attached to the outer surface of the electrode assembly 100, and a second portion 512 that extends from the first portion 511, is folded from the first portion 511, and is attached to the upper surface of the current collector plate 300. Alternatively, as shown in Figure 9, the second portion 512 may be attached to the upper surface of the electrode assembly 100, and the current collector plate 300 may be coupled to the upper surface of the second portion 512.

[0114] The first part 511 and the second part 512 may be constructed separately, but it is preferable that they be formed integrally. However, this description does not limit the scope of the rights of the present invention.

[0115] Referring to Figures 7 and 9, the first portion 511 is provided to cover the outermost exposed curved surface 111 of the folded segments 61 of the first blank portion 110, and at least a portion of the separator film adjacent to the exposed curved surface 111. The second portion 512 is provided to be attached to the upper surface of the electrode assembly 100 or to the upper surface of the current collector plate 300, so as to cover the upper portion of the folded segments of the first blank portion 110.

[0116] The first portion 511 may be larger than the second portion 512. However, the first portion 511 and the second portion 512 are not limited to such sizes. In an alternative embodiment, the first portion 511 may cover the entire side surface of the electrode assembly 100. Therefore, in Figure 3, the insulating tape covering portion P may also be included in the first portion 511.

[0117] The first portion 511 may be provided such that the size of the portion covering the exposed curved surface 111 of the first plain portion 110 is smaller than or equal to the size of the portion covering the separation film, but is not limited thereto.

[0118] Referring to Figure 6, the second portion 512 can be bent from the first portion 511 along the direction of arrow X in Figure 6, so that the second portion 512 can be attached to the upper surface of the current collector plate 300 as shown in Figure 7.

[0119] In Figures 5 to 7, the first portion 511 of the insulating tape 510 covers the entire side surface of the electrode assembly 100, but the invention is not limited to this, and the insulating tape 510 may be provided to cover only a portion of the side surface of the electrode assembly 100.

[0120] On the other hand, referring to another embodiment, Figure 8, at least one notch 515 may be formed in the second portion 512 of the insulating tape 510. When a notch 515 is formed in the second portion 512 of the insulating tape 510 in this way, the second portion 512 can be easily folded away from the first portion 511. Here, the lower end of the notch 515 may be positioned higher than the folded surface of the first plain portion 110.

[0121] The electrode assembly 100 according to the embodiment described above is applicable to a cylindrical battery cell 10.

[0122] Preferably, the cylindrical battery cell 10 may be a cylindrical battery cell 10 in which the form factor ratio (defined as the ratio of the diameter of the cylindrical battery cell to its height, i.e., the ratio of height (H) to relative diameter (Φ)) is greater than approximately 0.4.

[0123] Here, form factor refers to a value indicating the diameter and height of the cylindrical battery cell 10. A cylindrical battery cell 10 according to one embodiment of the present invention may be, for example, a 46110 cell, a 48750 cell, a 48110 cell, a 48800 cell, or a 46800 cell. In the numerical value indicating the form factor, the first two digits indicate the diameter of the cell, the following two digits indicate the height of the cell, and the last digit 0 indicates that the cross-section of the cell is circular.

[0124] A battery cell according to one embodiment of the present invention may be a cylindrical battery cell 10 which is a substantially cylindrical cell with a diameter of approximately 46 mm, a height of approximately 110 mm, and a form factor ratio of 0.418.

[0125] A battery cell according to another embodiment may be a cylindrical battery cell 10 which is a substantially cylindrical cell with a diameter of approximately 48 mm, a height of approximately 75 mm, and a form factor ratio of 0.640.

[0126] Furthermore, a battery cell according to another embodiment may be a cylindrical battery cell 10 which is a substantially cylindrical cell with a diameter of approximately 48 mm, a height of approximately 110 mm, and a form factor ratio of 0.418.

[0127] Furthermore, a battery cell according to another embodiment may be a cylindrical battery cell 10 which is a substantially cylindrical cell with a diameter of approximately 48 mm, a height of approximately 80 mm, and a form factor ratio of 0.600.

[0128] Furthermore, a battery cell according to another embodiment may be a cylindrical battery cell 10 which is a substantially cylindrical cell with a diameter of approximately 46 mm, a height of approximately 80 mm, and a form factor ratio of 0.575.

[0129] Traditionally, battery cells with a form factor ratio of approximately 0.4 or less have been used. Specifically, conventionally, 18650 cells and 21700 cells have been used. In the case of an 18650 cell, the diameter is approximately 18mm, the height is approximately 65mm, and the form factor ratio is 0.277. In the case of a 21700 cell, the diameter is approximately 21mm, the height is approximately 70mm, and the form factor ratio is 0.300.

[0130] Referring to Figures 2 and 3, a cylindrical battery cell 10 according to one embodiment of the present invention includes an electrode assembly 100, a cylindrical battery can 200, a current collector plate 300, cell terminals 400, and an insulating member 500.

[0131] The electrode assembly 100 is provided such that a sheet-like first electrode current collector and a second electrode current collector are wound in one direction with a separating membrane in between. The first electrode current collector may have positive or negative polarity, and the second electrode current collector may have the opposite polarity to the first electrode current collector. That is, the first electrode current collector may be a positive or negative electrode plate, and the second electrode current collector may be a negative or positive electrode plate with the opposite polarity to the first electrode current collector. However, for the sake of explanation, the following description will focus on the case where the first electrode current collector is a positive electrode plate and the second electrode current collector is a negative electrode plate. On the other hand, a detailed explanation of the electrode assembly 100 will be replaced by the explanation above.

[0132] The electrode assembly 100 may be connected to the insulating member 500 described above. The insulating member 500 is provided as an insulating tape 510 and may be connected to the side and top surfaces of the electrode assembly 100, or to the side surfaces of the electrode assembly 100 and the top surface of the current collector plate 300.

[0133] The first electrode current collector has the first electrode active material coated on one or both sides. Furthermore, there is a first blank portion 110 at the end of the first electrode current collector where the first electrode active material is not coated.

[0134] The second electrode current collector has the second electrode active material coated on one or both sides. Furthermore, there is a second blank portion 120 at the end of the second electrode current collector where the second electrode active material is not coated.

[0135] Furthermore, the first blank portion 110 of the first electrode current collector and the second blank portion 120 of the second electrode current collector are positioned to face in opposite directions. The first blank portion 110 extends toward the closed portion 210 of the battery can 200, and the second blank portion 120 extends toward the open portion 220 of the battery can 200.

[0136] 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 any active material known in the industry without limitation.

[0137] For example, the positive electrode active material is a material with the general chemical formula A[A x My O 2+z (A contains at least one element among Li, Na, and K; M contains at least one element selected from Ni, Co, Mn, Ca, Mg, Al, Ti, Si, Fe, Mo, V, Zr, Zn, Cu, Al, Mo, Sc, Zr, Ru, and Cr; x≧0, 1≦x + y≦2, -0.1≦z≦2; the stoichiometric coefficients x, y, and z are selected so that the compound maintains electrical neutrality) and may contain an alkali metal compound represented thereby.

[0138] As another example, the positive electrode active material is an alkali metal compound xLiM disclosed in U.S. Patent No. 6,677,082, U.S. Patent No. 6,680,143, etc. 1 O2-(1 - x)Li2M 2 O3(M 1 contains at least one element having an average oxidation state of 3; M 2 contains at least one element having an average oxidation state of 4; 0≦x≦1) and may be.

[0139] As 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 element selected from Ti, Si, Mn, Co, Fe, V, Cr, Mo, Ni, Nd, Al, Mg, and Al; M 2 contains at least one element selected from Ti, Si, Mn, Co, Fe, V, Cr, Mo, Ni, Nd, Al, Mg, Al, As, Sb, Si, Ge, V, and S; M 3contains 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 can be a lithium metal phosphate represented by Li3M2(PO4)3 [M contains at least one element selected from Ti, Si, Mn, Fe, Co, V, Cr, Mo, Ni, Al, Mg, and Al].

[0140] Desirably, the positive electrode active material may contain primary particles and / or secondary particles formed by aggregation of primary particles.

[0141] 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 with a potential less than 2V can also be used as the negative electrode active material. As the carbon material, both low-crystalline carbon and high-crystalline carbon can be used.

[0142] As the separation membrane, a porous polymer film, for example, a porous polymer film made of a polyolefin-based polymer such as an ethylene homopolymer, a propylene homopolymer, an ethylene / butene copolymer, an ethylene / hexene copolymer, an ethylene / methacrylate copolymer, etc., can be used alone or by laminating these. As another example, the separation membrane can use a normal porous non-woven fabric, for example, a non-woven fabric made of high-melting-point glass fibers, polyethylene terephthalate fibers, etc.

[0143] At least one surface of the separation membrane may include a coating layer of inorganic particles. Also, the separation membrane itself may consist of a coating layer of inorganic particles. The particles constituting the coating layer may have a structure bonded to a binder so that an interstitial volume exists between adjacent particles.

[0144] The inorganic particles can be made of an inorganic substance with a dielectric constant of 5 or more. As a non-limiting example, the inorganic particles are Pb(Zr,Ti)O3 (PZT), Pb1-x La x Zr 1-y Ti y O3(PLZT), PB(Mg3Nb) 2 / 3 It may contain at least one substance selected from the group consisting of O3-PbTiO3(PMN-PT), BaTiO3, hafnia (HfO2), SrTiO3, TiO2, Al2O3, ZrO2, SnO2, CeO2, MgO, CaO, ZnO, and Y2O3.

[0145] Electrolytes are, A + B - It can be a salt with a structure like this. Here, A + Li + na + , K + It contains alkali metal cations or ions consisting of combinations thereof, such as 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 one or more anions selected from the group consisting of the following.

[0146] Furthermore, electrolytes can be used after being dissolved in an organic solvent. Suitable organic solvents 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 mixtures thereof.

[0147] The battery can 200 is cylindrical in shape and houses the electrode assembly 100, and is electrically connected to the second electrode current collector of the electrode assembly 100. As a result, the battery can 200 may have the same polarity as the second electrode current collector. That is, if the second electrode current collector has negative polarity, the battery can 200 will also have negative polarity.

[0148] Here, the diameter of the battery can 200 is formed to be larger than the diameter of the electrode assembly 100, and a predetermined gap is provided between the battery can 200 and the electrode assembly 100, and as shown in Figure 3, the insulating member 500 may be provided such that the first portion 511 is interposed in the gap.

[0149] If the size of the electrode assembly 100 is increased while the size of the battery can 200 is determined according to the standard, the overall capacity of the battery cells will increase, while the distance between the battery can 200 and the electrode assembly 100 will decrease.

[0150] In other words, if the size of the electrode assembly 100 is increased to increase the overall capacity of the battery cell, the distance between the battery can 200 and the electrode assembly 100 decreases. Therefore, in order to increase the capacity of the battery cell, an insulating member 500 must be interposed in the reduced distance between the battery can 200 and the electrode assembly 100, and for this purpose, it is desirable that the thickness of the insulating member 500 be as thin as possible.

[0151] Referring to Figure 4, the battery can 200 may have a closed section 210 and an open section 220 that are located opposite each other.

[0152] For example, using Figure 4 as a reference, an opening 220 may be formed at the bottom of the battery can 200. The electrode assembly 100 is housed in the battery can 200 through the opening 220 formed at the bottom, and the electrolyte is also injected through the opening 220 formed at the bottom of the battery can 200.

[0153] In other words, the battery container 200 is a substantially cylindrical housing with an open portion 220 formed at its lower end, and is made of a conductive material such as metal. The material of the battery container 200 may be, but is not limited to, a conductive metal such as aluminum, steel, or stainless steel.

[0154] Furthermore, using Figure 4 as a reference, a closure portion 210 may be formed on the upper part of the battery can 200. A through hole 211 is formed in the closure portion 210, and the cell terminals 400 may be connected to the through hole 211 as shown in Figure 3.

[0155] Referring to Figure 3, an insulating plate 600 may be interposed between the closing portion 210 and the current collector plate 300. For example, the insulating plate 600 may be placed above the insulating tape 510 described above. Here, when the insulating plate 600 is provided above the insulating member 500, i.e., the insulating tape 510, the degree of design freedom is increased and the injection performance is also improved.

[0156] The insulating plate 600 prevents contact between the first blank portion 110 and the battery can 200, and between the current collector plate 300 and the battery can 200. That is, the insulating plate 600 is housed inside the battery can 200, covers at least a portion of the electrode assembly 100, and is configured to interrupt the electrical connection between the first blank portion 110 and the battery can 200. Therefore, the insulating plate 600 may be made of an insulating material. For example, the insulating plate 600 may include, but is not limited to, an insulating polymer material.

[0157] The insulating plate 600, together with the insulating tape 510, can prevent contact between the first blank portion 110 and the battery can 200, and between the current collector plate 300 and the battery can 200.

[0158] The insulating plate 600 may include, for example, an elastic material. Therefore, when vibration or external shock is applied to the cylindrical battery cell 10, the insulating plate 600 can absorb the shock in the process of being compressed elastically and then returning to its original state. This minimizes damage to the internal components of the battery cell even when vibration or external shock is applied to the battery cell.

[0159] The insulating plate 600 may have a central hole with a predetermined diameter in its center. For example, the insulating plate 600 may have a substantially circular central hole adjacent to the winding center. The presence of the central hole allows the cell terminal 400 to come into contact with the current collector plate 300 or the first blank section 110.

[0160] A beading section 240 and a crimping section 250 may be formed on the lower part of the battery can 200. The beading section 240 is formed in the region adjacent to the open section 220 of the battery can 200 by pushing the outer surface of the battery can 200 inward.

[0161] The beading portion 240 supports the electrode assembly 100, which has a size approximately corresponding to the width of the battery can 200, so as not to come out of the opening 220 formed at the bottom of the battery can 200, and can also function as a support portion on which the cap plate 230 is placed. In addition, the beading portion 240 supports the outer surface of the sealing gasket 260.

[0162] The crimping portion 250 is extended inward and bent into the battery can 200, and is provided to wrap around and secure the periphery of the cap plate 230 together with the sealing gasket 260. Here, the crimping portion 250 is formed at the bottom of the battery can 200 based on the arrangement of the battery can 200. For example, if the battery can 200 is arranged so that the cell terminals 400 are located at the top as shown in Figure 3, the crimping portion 250 is formed at the bottom of the battery can 200 based on Figure 3. And as shown in Figure 3, the crimping portion 250 is formed at the bottom of the beading portion 240.

[0163] However, the present invention does not exclude cases in which the battery can 200 does not have at least one of the beading portion 240 and the crimping portion 250. In the present invention, if the battery can 200 does not have at least one of the beading portion 240 and the crimping portion 250, fixing the electrode assembly 100, fixing the cap plate 230, or sealing the battery can 200 can be achieved through at least one of the following: additional application of a component that can function as a stopper to the electrode assembly 100, additional application of a structure on which the cap plate 230 can be mounted, and welding of the battery can 200 and the cap plate 230.

[0164] Referring to Figure 3, the crimping portion 250 is formed at the bottom of the beading portion 240. The crimping portion 250 has a shape that extends and bends to wrap around the periphery of the cap plate 230, which is positioned at the bottom of the beading portion 240. The cap plate 230 is fixed onto the beading portion 21 by the shape of the beaded portion 250 in this way. Of course, the crimping portion 250 may be omitted, and the cap plate 230 may be fixed to cover the opening of the battery can 200 through other fixing structures. For example, Korean Patent Publication No. 10-2019-0030016 by the present applicant discloses a cylindrical battery cell in which the beading portion is omitted, and such a structure may be adopted in the present invention.

[0165] The current collector plate 300 is electrically connected to the first electrode current collector at the upper part of the electrode assembly 100. The current collector plate 300 is made of a conductive metal material and is connected to the first blank portion 110 of the electrode assembly 100.

[0166] The current collector plate 300 can be attached to the upper part of a coupling surface formed by bending the end of the first blank portion 110 in a direction parallel to the current collector plate 300. The bending direction of the first blank portion 110 may be, for example, towards the winding center of the electrode assembly 100.

[0167] When the first blank portion 110 has this folded shape, the space occupied by the first blank portion 110 is reduced, which can improve energy density. In addition, the increased bonding area between the first blank portion 110 and the current collector plate 300 can improve bonding strength and reduce resistance.

[0168] The cell terminal 400 is made of a conductive metal material and is coupled to a through hole 211 formed in the closed portion 210 of the battery can 200, thereby electrically connecting to the current collector plate 300. The cell terminal 400 is then electrically connected to the first electrode current collector of the electrode assembly 100 through the current collector plate 300, thereby having positive polarity. In other words, the cell terminal 400 functions as the positive electrode terminal, which is the first electrode terminal. The battery can 200 is then electrically connected to the second electrode current collector of the electrode assembly 100, as described above, thereby having negative polarity.

[0169] The cell terminal 400 may be provided with a terminal insertion portion 410. The terminal insertion portion 410 is inserted into the battery can 200 through a through hole 211 formed in the closing portion 210 of the battery can 200, and its lower end may be electrically connected to the first blank portion 110.

[0170] The terminal insertion portion 410 can penetrate both the battery can 200 and the insulating plate 600 simultaneously and connect to the current collector plate 300 or the first blank portion 110. The lower end edge of the terminal insertion portion 410 can be pressed against a caulking jig and fixed to the through hole while being riveted toward the inner surface of the upper end of the battery can 200.

[0171] In other words, the lower edge of the terminal insertion portion 410 may have a shape that is bent toward the inner surface of the battery can 200 by applying a crimping jig. As a result, the maximum width of the end of the terminal insertion portion 410 may be made wider than the maximum width of the hole in the battery can 200 formed for the terminal insertion portion 410 to pass through.

[0172] On the other hand, in another embodiment, the terminal insertion portion 410 does not have to be bent toward the inner surface of the battery can 200. For example, referring to Figure 10, the terminal insertion portion 410 may be substantially cylindrical in shape, passing through a hole located approximately in the center of the upper surface of the battery can 200.

[0173] 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 selectively have a polygonal shape, a star shape, or a shape with legs extending from the center.

[0174] The terminal insertion portion 410 of the cell terminal 400 may pass through the central hole of the insulating plate 600. The diameter of the central hole of the insulating plate 600 may be larger than or the same as the diameter of the terminal insertion portion 410. The terminal insertion portion 410 of the cell terminal 400 may be electrically coupled to the current collector plate 300 by passing through the central hole of the insulating plate 600.

[0175] The insulating member 500 is interposed between the battery can 200 and the electrode assembly 100. In the specific description of the insulating member 500, any descriptions that are common with the description of the insulating member 500 of the electrode assembly 100 according to the embodiment described above will be replaced by the above description, and the explanation will focus on the parts that have not been described.

[0176] In a cylindrical battery cell 10 according to one embodiment of the present invention, each embodiment corresponding to the position of the current collector plate 300 will be described.

[0177] First, let's describe the case where the current collector plate 300 is attached to the upper surface portion of the multiple folded segments 61 of the first blank section 110, as shown in Figure 3. In this case, the second portion 512 of the insulating tape 510 covers the upper surface of the current collector plate 300, not the first blank section 110.

[0178] In other words, if the insulating tape 510 is composed of a first portion 511 and a second portion 512, the first portion 511 of the insulating tape 510 covers the side surface of the electrode assembly 100, for example, the outermost exposed curved surface 111 portion of the folded segments of the first plain portion 110, and at least a portion of the adjacent separator film. The second portion 512 is coupled to the upper surface of the current collector plate 300, which is coupled to the upper surface portion of the folded segments 61 of the first plain portion 110, and covers at least the edge portion of the current collector plate 300. This allows the insulating tape 510 to electrically insulate the first plain portion 110 and the current collector plate 300 from the battery can 200. The structure in which the second portion 512 extends from the first portion 511 is described above.

[0179] Preferably, the insulating tape 510 can be bent from the outermost exposed curved surface 111 of the multiple bent segments 61 of the first plain section 110 and bonded to the upper surface of the current collector plate 300.

[0180] The current collector plate 300 can be joined to the bent surface of the segment 61 of the first plain section 110 by various types of welding. Referring to Figure 11, a welded portion 310 is formed on the current collector plate 300 to be welded to the segment 61 of the first plain section 110, but the second portion 512 of the insulating tape 510 can be joined to the upper side of the current collector plate 300 either in contact with the outer edge of the welded portion 310 or at a distance from the outer edge so as not to interfere with the welded portion 310.

[0181] On the other hand, as another embodiment, with reference to Figure 9, a case will be described in which the second portion 512 of the insulating tape 510 is attached to the upper surface portion of the multiple folded segments 61 of the first plain portion 110, and the current collector plate 300 is attached to the upper side of the second portion 512 of the insulating tape 510.

[0182] The second portion 512 extends from the first portion 511 and is folded from the first portion 511 and attached to the folded surfaces of the multiple sub-sections 61 of the first plain portion 110. The current collector plate 300 is then positioned above the second portion 512 of the insulating tape 510. An insulating plate 600 is interposed between the current collector plate 300 and the battery can 200, thereby insulating the current collector plate 300 from the battery can 200.

[0183] The cap plate 230 is configured to seal the opening 220 of the battery can 200. To ensure rigidity, the cap plate 230 may be made of a metal material, for example.

[0184] The cap plate 230 seals the opening 220 formed at the lower end of the battery can 200. The cap plate 230 can be provided separately from the electrode assembly 100 and is nonpolar. That is, even if the cap plate 230 is made of a conductive metallic material, it will not have polarity. The fact that the cap plate 230 is nonpolar means that the cap plate 230 is electrically insulated from the battery can 200 and the cell terminals 400. Thus, the cap plate 230 does not need to have polarity, and its material does not necessarily need to be a conductive metal.

[0185] The cap plate 230 can be placed and supported on a beading portion 240 formed on the battery can 200. The cap plate 230 is also fixed by a crimping portion 250. A sealing gasket 260 may be interposed between the cap plate 230 and the crimping portion 250 of the battery can 200 to ensure airtightness of the battery can 200. That is, the sealing gasket 260 may be interposed between the periphery of the cap plate 230 and the open portion 220 of the battery can 200.

[0186] On the other hand, the battery can 200 of the present invention does not necessarily have to include at least one of the beading portion 240 and the crimping portion 250. In this case, the sealing gasket 260 may be interposed between a fixing structure provided on the open portion 220 side of the battery can 200 and the cap plate 230 in order to ensure the airtightness of the battery can 200.

[0187] A venting notch 231 may be formed in the cap plate 230 so that it ruptures when the internal pressure of the battery can 200 exceeds a critical value.

[0188] For example, the venting notches 231 may be formed on both sides of the cap plate 230 and may be formed on the surface of the cap plate 230 in at least one of a continuous circular pattern, a discontinuous circular pattern, and a linear pattern. Alternatively, the venting notches 231 may be formed in a variety of other patterns.

[0189] The venting notch 231 is formed at the bottom of the battery can 200 based on the position of the battery can 200, and may be provided so that when the venting notch 231 ruptures, the gas inside the battery can 200 is discharged from the bottom of the battery can 200.

[0190] For example, if the battery can 200 is positioned such that the cell terminals 400 are located at the top, as shown in Figure 3, the venting notch 231 may be formed at the bottom of the battery can 200 with reference to Figure 3.

[0191] The venting notch 231 may be formed in the cap plate 230 in a region that is thinner than the surrounding region.

[0192] Because the venting notch 231 is thinner than the surrounding area, it is more prone to rupture. If the internal pressure of the battery can 200 increases above a certain level, the venting notch 231 will rupture, and the gas generated inside the battery can 200 will be released.

[0193] For example, the venting notch 231 may be formed by partially reducing the thickness of the battery can 200 through notching on one or both sides of the cap plate 230.

[0194] In one embodiment of the present invention, the cylindrical battery cell 10 has a structure in which both the positive and negative terminals are located at the top, and therefore the structure of the top is more complex than the structure of the bottom.

[0195] Therefore, a venting notch 231 may be formed in the cap plate 230 that constitutes the lower surface of the cylindrical battery cell 10 in order to facilitate the smooth discharge of gas generated inside the battery can 200.

[0196] In this way, when the gas generated inside the battery can 200 of the cylindrical battery cell 10 is discharged from the bottom, it is also advantageous in terms of user safety. For example, if the cylindrical battery cell 10 is placed directly below the driver's seat of an electric vehicle, if the gas is discharged upwards, there is a risk of accidents involving the driver.

[0197] However, if the gas is discharged to the bottom of the battery can 200, as in the cylindrical battery cell 10 according to one embodiment of the present invention, the above-mentioned problems do not occur even if the cylindrical battery cell 10 is placed directly beneath the driver's seat of an electric vehicle.

[0198] Referring to Figure 3, it is desirable that the lower end of the cap plate 230 be positioned above the lower end of the battery can 200. In this case, even if the lower end of the battery can 200 is in contact with the ground or the bottom surface of the housing for the module or pack configuration, the cap plate 230 will not be in contact with the ground or the bottom surface of the housing for the module or pack configuration.

[0199] Therefore, the weight of the cylindrical battery cell 10 prevents the pressure required for the venting notch 231 to break from deviating from the design value, thereby ensuring smooth breaking of the venting notch 231.

[0200] Referring to Figure 3, the lower current collector plate 700 is coupled to the lower part of the electrode assembly 100. The lower current collector plate 700 is made of a conductive metal material such as aluminum, steel, copper, or nickel, and is electrically connected to the second blank portion 120 of the second electrode current collector.

[0201] Preferably, the lower current collector plate 700 is electrically connected to the battery can 200. For this purpose, the lower current collector plate 700 can be fixed by interposing at least a portion of its edge between the inner surface of the battery can 200 and the sealing gasket 260.

[0202] In one embodiment, at least a portion of the edge of the lower current collector plate 700 can be fixed to the beading portion 240 formed on the lower end of the battery can 200 by welding, while being supported by the lower end surface of the beading portion 240. In a modified embodiment, at least a portion of the edge of the lower current collector plate 700 can be directly welded to the inner wall surface of the battery can 200.

[0203] Preferably, at least a portion of the lower current collector plate 700, excluding the portion connected to the beading portion, may be joined to the curved surface of the second plain portion 120 by welding, for example, laser welding.

[0204] For example, at least a portion of the edge of the lower current collector plate 700 can be electrically coupled to the upper and lower surfaces of the beading portion 240 that are adjacent to the crimping portion 250.

[0205] On the other hand, an electrode assembly 100 according to one embodiment of the present invention includes a first electrode current collector and a second electrode current collector, the first electrode current collector includes a first blank portion, and the second electrode current collector may include a second blank portion. At least a portion of the first blank portion and / or the second blank portion may be divided into a plurality of subsections. The structure of the subsections will be described in detail below.

[0206] Referring to Figure 12, in the plain portion 43 of the electrode plate 60, the heights of the core-side plain portion B1 and the outer peripheral plain portion B3 are 0 or greater, and are relatively lower than the intermediate plain portion B2. Furthermore, the heights of the core-side plain portion B1 and the outer peripheral plain portion B3 may be the same or different.

[0207] Preferably, the intermediate plain section B2 may include at least a portion of a plurality of subsections 61. The height of the plurality of subsections 61 may increase in stages from the core side to the outer periphery side.

[0208] The section 61 may be notched with a laser. The section 61 may be formed by known metal foil cutting processes such as ultrasonic cutting or punching.

[0209] In Figure 12, it is desirable to provide a predetermined gap between the lower end of the cutting line between the segment 61 (C4 in Figure 13) and the active material layer 42 in order to prevent damage to the active material layer 42 and / or the insulating coating layer 44 when the plain section 43 is bent. This is because stress is concentrated near the lower end of the cutting line when the plain section 43 is bent. The gap is preferably 0.2 to 4 mm. If the gap is adjusted to the above numerical range, it is possible to prevent damage to the active material layer 42 and / or the insulating coating layer 44 near the lower end of the cutting line due to the stress generated when the plain section 43 is bent. In addition, the gap can prevent damage to the active material layer 42 and / or the insulating coating layer 44 due to tolerances when the segment 61 is notched or cut. Preferably, when the electrode plate 60 is wound up, at least a portion of the insulating coating layer 44 may be exposed to the outside of the separation film. In this case, when the segment 61 is bent, the insulating coating layer 44 can support the bending point.

[0210] Multiple subsections 61 may form multiple subsection groups from the core side to the outer periphery side. At least one of the width, height, and spacing pitch of subsections belonging to the same subsection group may be substantially the same.

[0211] Figure 13 shows the definitions of the width, height, and spacing pitch of the section 61 according to an embodiment of the present invention.

[0212] Referring to Figure 13, the width C1, height C2, and separation pitch C3 of the segment 61 are designed to prevent the plain section 43 from tearing during bending and to improve welding strength, while sufficiently increasing the number of overlapping layers of the plain section 43 to prevent abnormal deformation of the plain section 43. Abnormal deformation refers to the plain section below the bending point collapsing and deforming irregularly without being able to maintain a straight line.

[0213] Preferably, the width C1 of the segment 61 can be adjusted within the range of 1 mm to 6 mm. If C1 is less than 1 mm, when the segment 61 is bent toward the core, a region that does not overlap or an empty space (gap) will be created that does not sufficiently ensure welding strength. On the other hand, if C1 exceeds 6 mm, when the segment 61 is bent, the plain portion 43 near the bending point may tear due to stress.

[0214] Furthermore, the height of the segment 61 can be adjusted within the range of 2 mm to 10 mm. If C2 is less than 2 mm, when the segment 61 is bent toward the core, areas that do not overlap or empty spaces (gaps) will be created to the extent that sufficient welding strength can be ensured. On the other hand, if C2 exceeds 10 mm, it becomes difficult to manufacture the electrode while maintaining uniform flatness of the plain area in the winding direction X. That is, the plain area becomes higher and swell occurs. Also, the separation pitch C3 of the segment 61 can be adjusted within the range of 0.05 mm to 1 mm. If C3 is less than 0.05 mm, when the segment 61 is bent, the plain area 43 near the bending point may tear due to stress. On the other hand, if C3 exceeds 1 mm, when the segment 61 is bent, the segment 61 may not overlap to the extent that sufficient welding strength can be ensured, or empty spaces (gaps) may be created.

[0215] Referring to Figure 13, a cutting portion 62 is interposed between adjacent segment 61 in the winding direction X. The cutting portion 62 corresponds to the space created when the plain portion 43 is removed. Preferably, the lower corner of the cutting portion 62 can be rounded (see enlarged section). The rounded shape can relieve the stress applied to the lower end of the cutting portion 62 when the electrode plate 60 is wound and / or when the segment 61 is bent.

[0216] Referring further to Figure 12, the width d of the plain section B1 on the core side. B1 The design is based on the condition that when the segment 61 of the intermediate plain section B2 is folded toward the core, it does not block the cavity in the core of the electrode assembly.

[0217] As an example, the width d of the plain section B1 on the core side. B1The bending length of the segment 61 of group 1 may increase in proportion to the bending length of the segment 61. The bending length corresponds to the height of the segment 61 relative to the bending point (63 in Figure 13). Referring to Figure 13, C4 indicates the lowest point of the bendable position. 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 segment 61. Specifically, the bending point can be set at a predetermined point C2 of the segment 61 relative to C4. The predetermined point can be set so as to prevent the stress generated when the segment 61 is bent from causing physical damage to the active material layer 42 or the insulating coating layer 44, and so as to ensure a sufficient number of layers overlapping radially when the segment 61 is bent radially in the electrode assembly, thereby ensuring sufficient welding strength when the current collector plate is welded to the bent region of the segment 61.

[0218] In a specific example, if the electrode plate 60 is used to manufacture an electrode assembly for a cylindrical cell with form factor 46800, the width d of the plain core portion B1 is... B1 This can be set to 180mm to 350mm depending on the diameter of the core of the electrode assembly.

[0219] In one example, the width of each segment group may be designed to constitute the same winding turn of the electrode assembly.

[0220] Here, the winding turns can be counted with reference to the end of the plain section B1 on the core side when the electrode plate 60 is in the wound-up state.

[0221] In other examples, the width of each segment group may be designed to constitute at least one winding turn of the electrode assembly.

[0222] In further examples, the width and / or height and / or spacing of sections 61 belonging to the same section group may increase or decrease gradually and / or stepwise and / or irregularly within the group.

[0223] Groups 1 to 8 are merely examples of segment groups. The number of groups, the number of segment segments 61 included in each group, and the width of the groups can be suitably adjusted so that the segment segments 61 overlap in multiple layers, thereby maximally distributing stress during the bending process of the plain section 43 and ensuring sufficient welding strength.

[0224] In other examples, the height of the plain outer portion B3 may decrease gradually or in stages.

[0225] In further examples, the segmentation structure of the intermediate plain section B2 can be extended to the outer plain section B3 (see dotted line). In this case, the outer plain section B3, like the intermediate plain section B2, may also contain multiple segments. In this case, the segments of the outer plain section B3 may have a larger width and / or height and / or spacing pitch than those of the intermediate plain section B2. Selectively, the segmentation structure of the outer plain section B3 may be substantially identical to the outermost group of segments of the intermediate plain section B2.

[0226] 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 plain core portion B1 is... B1 The width can be 180mm to 350mm. The width of Group 1 can be 35% to 40% of the width of the plain core section 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 of the plain outer section B3 is d. B3 The width of the plain section B1 on the core side can be between 180mm and 350mm, similar to the width of the plain section B1 on the core side.

[0227] The reason why the widths of groups 1 through 8 do not show a constant increasing or decreasing pattern is that while the width of the subintercepts gradually increases from group 1 to group 8, the number of subintercepts contained within a group is limited to an integer. Therefore, the number of subintercepts may decrease in a particular subintercept group. Consequently, the width of the groups may show an irregular pattern of change from the core side to the outer edge, as illustrated above.

[0228] In other words, when the winding widths for three consecutively adjacent segment groups in the circumferential direction of the electrode assembly are W1, W2, and W3, respectively, the combination of segment groups may include one in which W3 / W2 is smaller than W2 / W1.

[0229] In the specific example mentioned above, groups 4 through 6 fall into this category. The ratio of group 5 to group 4 is 120% to 130%, and the ratio of group 6 to group 5 is 100% to 120%, which is smaller than 120% to 130%.

[0230] Referring to Figure 14, the electrode plate 70 is substantially identical to that in Figure 12, except that the shape of the segment 61' has been changed from a rectangle to a trapezoid.

[0231] Figure 15 shows the definitions of the width, height, and spacing pitch of the trapezoidal section 61'.

[0232] Referring to Figure 15, the width D1, height D2, and separation pitch D3 of the segment 61' are designed to prevent the plain section 43 from tearing near the bending point during bending and to ensure sufficient welding strength, while also preventing abnormal deformation of the plain section 43 by sufficiently increasing the number of overlapping layers of the plain section 43.

[0233] Preferably, the width D1 of the segment 61' can be adjusted in the range of 1 mm to 6 mm. If D1 is less than 1 mm, when the segment 61' is bent toward the core, there is a risk that areas or gaps will occur where the segment 61' do not overlap to the extent that sufficient welding strength can be ensured. On the other hand, if D1 exceeds 6 mm, when the segment 61 is bent, the plain section 43 near the bending point may break due to stress. The height of the segment 61' can also be adjusted in the range of 2 mm to 10 mm. If D2 is less than 2 mm, when the segment 61' is bent toward the core, there is a risk that areas or gaps will occur where the segment 61' do not overlap to the extent that sufficient welding strength can be ensured. On the other hand, if D2 exceeds 10 mm, it is difficult to manufacture the electrode current collector while maintaining uniform flatness of the plain section 43 in the winding direction. Furthermore, the separation pitch D3 of the segment 61' can be adjusted within the range of 0.05 mm to 1 mm. If D3 is less than 0.05 mm, when the segment 61' is bent, the plain section 43 near the bending point D4 may tear due to stress. On the other hand, if D3 exceeds 1 mm, when the segment 61' is bent, there is a risk that areas where the segment 61' do not overlap or empty spaces (gaps) will occur to the extent that sufficient welding strength can be ensured.

[0234] In the winding direction X, a cutting portion 62 is interposed between adjacent segmental sections 61'. The cutting portion 62 corresponds to the space created when the plain section 43 is removed. Preferably, the lower corner of the cutting portion 62 may be rounded (see enlarged section). The rounded shape can relieve stress when the segmental sections 61' are bent.

[0235] Referring to Figures 14 and 15, the lower interior angle θ of the trapezoidal segments 61' can gradually increase from the core side to the outer circumference. As the radius of the electrode assembly increases, the curvature increases. If the lower interior angle θ of the segments 61' increases with the radius of the electrode assembly, the stress generated in the radial and circumferential directions when the segments 61' are bent can be relieved. Furthermore, as the lower interior angle θ increases, the overlapping area and the number of overlapping layers with the inner segments 61' when the segments 61' are bent also increase, thereby ensuring uniform welding strength in the radial and circumferential directions and forming a flat bent surface.

[0236] In one example, if the electrode plate 70 is used to manufacture an electrode assembly of a cylindrical cell with form factor 46800, the interior angle of the segment 61' may increase in steps between 60° and 85° as the radius of the electrode assembly increases from 4 mm to 22 mm.

[0237] In other examples, the height of the outer plain section B3 may decrease gradually or in stages, similar to the embodiments described above. Furthermore, the segmentation structure of the intermediate plain section B2 can extend to the outer plain section B3 (see dotted line). In this case, the outer plain section B3 may also include multiple segments, similar to the intermediate plain section B2. In this case, the segments of the outer plain section B3 may have a greater width and / or height and / or spacing pitch than those of the intermediate plain section B2. Optionally, the segmentation structure of the outer plain section B3 may be substantially identical to the outermost group of segments in the intermediate plain section B2.

[0238] In a specific example, 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 plain core portion B1 is... B1The width can be 180mm to 350mm. The width of Group 1 can be 35% to 40% of the width of the plain core section 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 of the plain outer section B3 is d. B3 The width of the plain section B1 on the core side can be between 180mm and 350mm, similar to the width of the plain section B1 on the core side. The reason why the widths of groups 1 to 8 do not show a constant increasing or decreasing pattern is that the width of the segment gradually increases from group 1 to group 8, but the number of segment segments included in a group is limited to an integer. Therefore, the number of segment segments may decrease in a particular segment group. Consequently, the width of the groups may show an irregular pattern of change from the core side to the outer periphery, as illustrated above.

[0239] In other words, when the winding widths for three consecutively adjacent segment groups in the circumferential direction of the electrode assembly are W1, W2, and W3, respectively, the combination of segment groups may include one in which W3 / W2 is smaller than W2 / W1.

[0240] In the specific example mentioned above, groups 4 through 6 fall into this category. The ratio of group 5 to group 4 is 120% to 130%, and the ratio of group 6 to group 5 is 100% to 120%, which is smaller than 120% to 130%.

[0241] Referring to Figure 16, the plain portion 43a of the electrode current collector includes a core-side plain portion B1 adjacent to the core of the electrode assembly 100, an outer-circumferential plain portion B3 adjacent to the outer-circumferential surface of the electrode assembly 100, and an intermediate plain portion B2 interposed between the core-side plain portion B1 and the outer-circumferential plain portion B3.

[0242] The height of the plain core section B1 is relatively lower than the height of the intermediate plain section B2. Also, the folded length of the innermost plain section 43a in the intermediate plain section B2 is the same as or shorter than the radial length R of the plain core section B1. The folded length H corresponds to the height of the plain section 43a relative to the point where the plain section 43a is folded (h in Figure 13, h in Figure 15).

[0243] Therefore, even if the plain intermediate section B2 is bent, the bent portion does not block the cavity 102 in the core of the electrode assembly 100. If the cavity 102 is not blocked, there is no interference with the electrolyte injection process, and the efficiency of electrolyte injection is improved. Furthermore, a welding jig can be inserted through the cavity 102 to easily perform the welding process between the negative electrode (or positive electrode) current collector plate and the battery can (or rivet terminal).

[0244] The height of the plain outer section B3 is relatively lower than the height of the plain middle section B2. Therefore, it is possible to prevent the beading section of the battery can from coming into contact with the plain outer section B3 during the process in which the beading section is pressed against the plain outer section B3.

[0245] In one modified example, the height of the plain outer portion B3 may decrease gradually or in stages, unlike in Figure 16. Also, in Figure 16, the height of the intermediate plain portion B2 is equal in a portion of the outer edge, but the height of the intermediate plain portion B2 may increase gradually or in stages from the boundary between the core-side plain portion B1 and the intermediate plain portion B2 to the boundary between the intermediate plain portion B2 and the outer edge plain portion B3.

[0246] The lower plain section 43b has the same structure as the upper plain section 43a. In one modified example, the lower plain section 43b may have the structure of a conventional electrode current collector or the structure of an electrode current collector of another embodiment (modified example).

[0247] The ends 101 of the upper plain portion 43a and the lower plain portion 43b can be bent from the outer circumference side to the core side of the electrode assembly 100. In this case, the core-side plain portion B1 and the outer circumference-side plain portion B3 are not substantially bent.

[0248] When the intermediate plain section B2 includes multiple subsections, the bending stress is relieved, which prevents the plain section 43a near the bending point from tearing or deforming abnormally. Furthermore, when the width and / or height and / or spacing pitch of the subsections are adjusted within the numerical range of the above-described embodiment, the subsections overlap in sufficient quantities to ensure sufficient welding strength while being bent toward the core, and do not form any gaps in the bent surface (the surface viewed from the Y-axis direction).

[0249] Referring to Figure 17, the electrode assembly 110 is substantially identical to the electrode assembly 100 in Figure 16, except that the height of the outer plain section B3 is substantially the same as the height of the outermost part of the intermediate plain section B2. The outer plain section B3 may include multiple subsections.

[0250] In the electrode assembly 110, the height of the core-side plain section B1 is relatively lower than the height of the intermediate plain section B2. Also, the bend length H of the innermost plain section in the intermediate plain section B2 is the same as or shorter than the radial length R of the core-side plain section B1.

[0251] Therefore, even if the plain intermediate section B2 is bent, the bent portion does not block the cavity 112 in the core of the electrode assembly 110. If the cavity 112 is not blocked, there is no interference with the electrolyte injection process, and the efficiency of electrolyte injection is improved. Furthermore, a welding jig can be inserted through the cavity 112 to easily perform the welding process between the negative electrode (or positive electrode) current collector plate and the battery can (or rivet terminal).

[0252] In one modified example, the structure in which the height of the intermediate plain section B2 gradually or stepwise increases from the core side toward the outer circumference can be extended to the outer circumference plain section B3. In this case, the height of the plain section 43a can gradually or stepwise increase from the boundary between the core side plain section B1 and the intermediate plain section B2 to the outermost surface of the electrode assembly 110.

[0253] The lower non-land portion 43b has the same structure as the upper non-land portion 43a. In a modified example, the lower non-land portion 43b may have the structure of a conventional electrode current collector or the structure of an electrode current collector of other embodiments (modified examples).

[0254] The end portions 111 of the upper non-land portion 43a and the lower non-land portion 43b can be bent from the outer peripheral side to the core side of the electrode assembly 110. At this time, the non-land portion B1 on the core side is not substantially bent.

[0255] When the intermediate non-land portion B2 and the outer peripheral side non-land portion B3 include a plurality of divided sections, the bending stress is relaxed, so that it is possible to prevent the non-land portions 43a and 43b near the bending point from being broken or abnormally deformed. Further, when the width and / or height and / or separation pitch of the divided sections are adjusted within the numerical ranges of the above-described embodiments, the divided sections are overlapped multiple times to ensure sufficient welding strength while being bent to the core side, and no space (gap) is formed on the bending surface (the surface viewed from the Y-axis direction).

[0256] FIG. 18 is a diagram schematically showing the configuration of a battery pack according to an embodiment of the present invention.

[0257] Referring to FIG. 18, 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 the battery cell according to the above-described embodiment. For the sake of illustration, components such as a bus bar, a cooling unit, and external terminals for the electrical connection of the cylindrical battery cell 10 are not shown.

[0258] The battery pack 800 is mounted on an automobile 900. The automobile 900 can be, for example, 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.

[0259] FIG. 19 is a diagram for explaining an automobile including the battery pack of FIG. 18.

[0260] Referring to FIG. 19, a vehicle 900 according to an embodiment of the present invention includes a battery pack 800 according to an embodiment of the present invention. The vehicle 900 operates by receiving power supply from the battery pack 800 according to an embodiment of the present invention.

[0261] As described above, the present invention has been described with reference to limited embodiments and drawings. However, the present invention is not limited thereto, and it is needless to say that various modifications and variations are possible within the equivalent scope of the technical idea and claims of the present invention by those having ordinary knowledge in the technical field to which the present invention pertains.

Industrial Applicability

[0262] The present invention relates to an electrode assembly, a cylindrical battery cell, a battery pack including the same, and a vehicle, and in particular, it can be used in the secondary battery related industry.

Explanation of Reference Numerals

[0263] 10 Cylindrical battery cell 21 Beading portion 42 Active material layer 43 Plain portion 44 Insulating coating layer 60 Electrode plate 61 Cut piece 62 Cutting portion 70 Electrode plate 100 Electrode assembly 101 End portion 102 Cavity 110 Electrode assembly, first plain portion 111 End portion 112 Cavity 120 Second plain portion 200 Battery can 210 Closing portion 211 Through hole 220 Open portion 230 Cap plate 231 Venting notch 240 Beading portion 250 Crimping portion 260 Sealing Gasket 300 Current collector plate 310 Welded section 400 cell terminals 410 Terminal insertion section 500 Insulating material 510 Insulating Tape 511 Part 1 512 Part 2 515 Notch 600 Insulating board 700 Lower current collector plate 800 Battery Pack 810 Pack Housing 900 cars

Claims

1. A jelly roll type electrode assembly having a structure in which a sheet-like first electrode current collector and a second electrode current collector, and a separation membrane interposed between the first electrode current collector and the second electrode current collector, are wound in one direction, The first electrode current collector includes a first plain portion at the long end where the active material layer is not coated, The first blank portion is exposed to the outside of the separation membrane while forming multiple winding turns with respect to the center of the electrode assembly, and is used as an electrode tab itself. The electrode assembly includes an insulating member that covers the exposed curved surface of the first plain portion located at the outermost winding turn among the plurality of winding turns that is exposed on the outer circumferential surface of the electrode assembly.

2. The electrode assembly according to claim 1, wherein the insulating member is an insulating tape having an adhesive layer formed on the surface facing the exposed curved surface of the first plain portion.

3. The electrode assembly according to claim 2, wherein the insulating tape is a single-sided tape with an adhesive layer formed on only one side.

4. The electrode assembly according to claim 1, wherein the insulating member is a heat-shrinkable tube that shrinks when heat is applied.

5. The electrode assembly according to claim 1, wherein the insulating member is formed wider than the width of the exposed curved surface so as to cover the exposed curved surface of the first plain portion.

6. The electrode assembly according to claim 2, wherein the thickness of the insulating tape is 10 μm or more and 50 μm or less.

7. The electrode assembly according to claim 2, wherein the insulating tape is provided so as to enclose the electrode assembly in one or more layers.

8. The electrode assembly according to claim 2, wherein the insulating tape is manufactured from a material that prevents thermal deformation when the electrode assembly generates heat.

9. The electrode assembly according to claim 8, wherein the insulating tape is manufactured from polyimide, polyethylene terephthalate, or polypropylene.

10. The electrode assembly according to claim 9, wherein the insulating tape includes polyimide in the portion that covers the exposed curved surface of the first plain portion.

11. The electrode assembly according to claim 9, wherein the insulating tape comprises polyimide in the portion covering the exposed curved surface of the first plain portion, and polyethylene terephthalate in the portion covering the exposed curved surface of the separation membrane adjacent to the exposed curved surface.

12. The electrode assembly according to any one of claims 2, 3, and 6 to 11, wherein at least a portion of the first blank portion is divided into a plurality of sub-sections along the winding direction of the electrode assembly.

13. The electrode assembly according to claim 12, wherein the plurality of segments are bent along the radial direction of the electrode assembly.

14. The electrode assembly according to claim 12, wherein the plurality of segments are overlapping in multiple layers along the radial direction of the electrode assembly.

15. The electrode assembly according to claim 13, wherein the insulating tape is attached to at least a portion of the outer circumferential surface of the electrode assembly and at least a portion of the upper surface of the electrode assembly.

16. The aforementioned insulating tape is A first portion is attached to the outer surface of the electrode assembly, A second portion is extended from the first portion, bent from the first portion and attached to the upper surface of the electrode assembly, The electrode assembly according to claim 15, including the following:

17. The electrode assembly according to claim 16, wherein the first portion is provided to cover at least a portion of the outermost exposed curved surface of the folded plurality of segments of the first plain portion and the adjacent portion of the separation membrane.

18. The electrode assembly according to claim 17, wherein the first portion is such that the size of the portion covering the outermost exposed curved surface of a plurality of subsections of the first plain portion is smaller than or equal to the size of the portion covering the separation membrane adjacent to the exposed curved surface.

19. The electrode assembly according to claim 16, wherein the second part covers the upper portion of the folded segments of the first plain part.

20. The electrode assembly according to claim 16, wherein the first portion is provided to be larger than the second portion.

21. The electrode assembly according to claim 16, wherein at least one notch is formed in the second portion.

22. The electrode assembly according to claim 21, wherein the lower end of the notch is positioned higher than the bent surface of the first plain portion.

23. A jelly roll type electrode assembly having a structure in which a sheet-like first electrode current collector and a second electrode current collector, and a separation membrane interposed between the first electrode current collector and the second electrode current collector are wound in one direction, wherein the first electrode current collector includes a first plain portion at the long end where the active material layer is not coated, and the first plain portion is exposed to the outside of the separation membrane while forming a plurality of winding turns with respect to the center of the electrode assembly, and is used as an electrode tab itself, A cylindrical battery can containing the electrode assembly and electrically connected to the second electrode current collector, A current collector plate electrically connected to the first electrode current collector, The cell terminal connected to the current collector plate, An insulating member that covers the exposed curved surface of the first plain portion located at the outermost winding turn among the plurality of winding turns that is exposed on the outer surface of the electrode assembly, A cylindrical battery cell, including one.

24. The diameter of the battery can is formed to be larger than the diameter of the electrode assembly, and a predetermined gap is provided between the battery can and the electrode assembly. The cylindrical battery cell according to claim 23, wherein the insulating member is interposed at the aforementioned interval.

25. The cylindrical battery cell according to claim 23, wherein the insulating member is an insulating tape having an adhesive layer formed on the surface facing the exposed curved surface of the first plain portion.

26. The cylindrical battery cell according to claim 25, wherein at least a portion of the first blank portion is divided into a plurality of segments along the winding direction of the electrode assembly.

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

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

29. The aforementioned insulating tape is A first portion is attached to the outer surface of the electrode assembly, A second portion extends from the first portion, is bent from the first portion and attached to the upper surface of the current collector plate connected to the electrode assembly, A cylindrical battery cell according to claim 27, including the following:

30. The cylindrical battery cell according to claim 29, wherein the first portion is provided to cover the outermost exposed curved portion of the folded segments of the first plain portion, and at least a portion of the separator membrane adjacent thereto.

31. The cylindrical battery cell according to claim 30, wherein the second portion is provided so as to cover a current collector plate joined to the upper surface portions of a plurality of folded segments of the first plain portion.

32. The cylindrical battery cell according to claim 31, wherein the insulating tape is bent from the end of the exposed curved surface of the first plain portion and joined to the upper side of the current collector plate.

33. The current collector plate has a welded portion formed by welding the first plain portion to it. The cylindrical battery cell according to claim 32, wherein the second portion is coupled to the upper side of the current collector plate so as not to interfere with the weld, either in contact with the outer edge of the weld or at a distance from the outer edge.

34. The aforementioned insulating tape is A first portion is attached to the outer surface of the electrode assembly, A second portion extends from the first portion, is folded from the end of the first portion and attached to the folded surface of the plurality of segments of the first plain portion, A cylindrical battery cell according to claim 27, including the following:

35. The cylindrical battery cell according to claim 34, wherein the current collector plate is coupled to the upper side of the second portion of the insulating tape.

36. The battery can is formed with a closed section and an open section that are located opposite each other. The cylindrical battery cell according to claim 23, further comprising a cap plate configured to seal the open portion of the battery can.

37. The cylindrical battery cell according to claim 36, wherein the cap plate is provided electrically separated from the electrode assembly and is nonpolar.

38. A through hole is formed in the closed portion. The cylindrical battery cell according to claim 36, wherein the cell terminals are connected to the through-holes.

39. The cylindrical battery cell according to claim 38, further comprising an insulating plate interposed between the closing portion and the current collector plate.

40. The cylindrical battery cell according to claim 39, wherein the insulating plate comprises an insulating polymer material.

41. The cylindrical battery cell according to claim 39, wherein the insulating plate is made of an elastic material.

42. The cylindrical battery cell according to claim 39, wherein the insulating plate has a central hole in the center having a predetermined diameter.

43. The cell terminal is provided with a terminal insertion portion, The cylindrical battery cell according to claim 42, wherein the terminal insertion portion is inserted into the battery can through the through hole.

44. The cylindrical battery cell according to claim 43, wherein the cell terminal is fixed to the through hole by riveting the lower peripheral edge of the terminal insertion portion toward the inner surface of the upper end of the battery can.

45. The cylindrical battery cell according to claim 43, wherein the diameter of the central hole of the insulating plate is greater than or equal to the diameter of the terminal insertion portion.

46. The cylindrical battery cell according to claim 43, wherein the terminal insertion portion of the cell terminal penetrates the central hole of the insulating plate.

47. The cylindrical battery cell according to claim 43, wherein the terminal insertion portion of the cell terminal penetrates the central hole of the insulating plate and is electrically connected to the current collector plate.

48. This includes a sealing gasket interposed between the periphery of the cap plate and the open portion of the battery can. The battery can includes a beading portion that is pushed inward into the battery can in a region adjacent to the opening. The cylindrical battery cell according to claim 36, wherein the battery can includes a crimping portion that extends inward from the battery can, is bent, and wraps around and secures the periphery of the cap plate together with the sealing gasket.

49. The cylindrical battery cell according to claim 48, wherein the crimping portion is formed at the lower part of the battery can, based on the arrangement of the battery can.

50. The cylindrical battery cell according to claim 36, wherein the cap plate includes a venting notch that ruptures when the internal pressure of the battery can exceeds a critical value.

51. The cylindrical battery cell according to claim 50, wherein the venting notches are formed on both sides of the cap plate and are formed on the surface of the cap plate in a pattern of at least one of a continuous circular pattern, a discontinuous circular pattern, and a linear pattern.

52. The cylindrical battery cell according to claim 50, wherein the venting notch is formed at the bottom of the battery can with respect to the arrangement of the battery can, and when the venting notch ruptures, the gas inside the battery can is discharged from the bottom of the battery can.

53. The cylindrical battery cell according to claim 48, further comprising a lower current collector plate coupled to the lower part of the electrode assembly.

54. The cylindrical battery cell according to claim 53, wherein at least a portion of the edge of the lower current collector plate is electrically connected to the beading portion, and at least a portion of the other portion excluding the edge is electrically connected to the second blank portion of the second electrode current collector.

55. The cylindrical battery cell according to claim 54, wherein at least a portion of the edge of the lower current collector plate is electrically connected to the upper and lower surfaces of the beading portion that are adjacent to the crimping portion.

56. The cylindrical battery cell according to claim 55, wherein the lower current collector plate and the beading portion are joined by laser welding.

57. The cylindrical battery cell according to claim 23, wherein the insulating member has a thickness corresponding to the distance between the current collector plate and the inner surface of the upper end of the battery can.

58. The cylindrical battery cell according to claim 23, wherein the thickness of the insulating member is 100 μm to 500 μm.

59. A battery pack comprising at least one cylindrical battery cell as described in any one of claims 23 to 58.

60. An automobile comprising at least one battery pack as described in claim 59.

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