Electrode assembly, cylindrical battery, and system including the same

Abstract

The present invention discloses an electrode assembly and a cylindrical battery including the same. The electrode assembly has a structure in which a first electrode sheet, a second electrode sheet, and a separator sheet interposed therebetween are wound in one direction. A cavity is provided along the winding central axis of the electrode assembly, and a mesh-like tubular support is disposed along the longitudinal direction of the cavity. A wireless pressure sensor or a wireless temperature sensor may be disposed at at least one point on the outer surface or inner surface of the mesh-like tubular support. A cylindrical battery includes such an electrode assembly.

Description

[Technical Field]

[0001] The present invention relates to an electrode assembly, a cylindrical battery, and a system, and more particularly to an electrode assembly having an improved core structure, a cylindrical battery, and a system including the same.

[0002] This application claims priority based on Korean Patent Application No. 10-2021-0131993, filed on October 5, 2021, and the entire contents disclosed in the specification and drawings of that application are incorporated herein by reference. [Background technology]

[0003] In recent years, as cylindrical batteries have become more widely used in electric vehicles, electrically assisted bicycles (electric bicycles), electric motorcycles, etc., the number of form factors available for cylindrical batteries has increased to increase their output and capacity.

[0004] Cylindrical battery form factors are designated as 1865, 2170, 4680, etc. The first two digits of the form factor indicate the diameter of the cylindrical battery, and the remaining digits indicate the height of the cylindrical battery. For example, 4680 is a cylindrical battery form factor with a diameter of 46 mm and a height of 80 mm.

[0005] A cylindrical battery includes an electrode assembly made by winding two long electrode sheets with opposite polarities, with a separator interposed between them, using a winding means such as a center pin or bobbin.

[0006] The winding means may be removed to improve electrolyte impregnation and provide a tab welding path in the center of the electrode assembly, leaving a cavity along the length of the electrode assembly where the winding means was removed.

[0007] On the other hand, as the form factor of a cylindrical battery increases, the amount of heat generated inside the battery during charging and discharging also increases. This is because a larger form factor increases the charging and discharging current, which in turn increases Joule heat generated by the internal resistance of the electrode assembly.

[0008] Heat generated during charging and discharging is one of the causes of swelling of the electrode assembly, and as the form factor of cylindrical batteries increases, swelling becomes more likely to occur.

[0009] When swelling occurs in the electrode assembly (when the electrode assembly expands), stress is generated in the radial direction, and as a result, the cavity in the core is unable to maintain its shape and collapses.

[0010] FIG. 1 is a diagram showing how the core of an electrode assembly 10 can no longer maintain its shape and collapses when swelling occurs in the prior art.

[0011] In the figure, reference numeral 11 denotes a first electrode sheet having a first polarity, reference numeral 12 denotes a second electrode sheet having a second polarity opposite to the first polarity, and reference numeral 13 denotes a separator sheet interposed between the first electrode sheet 11 and the second electrode sheet 12.

[0012] There are two separator sheets 13. One is interposed between the first electrode sheet 11 and the second electrode sheet 12, and the other is used as a film for winding up the two electrode sheets stacked so as to face each other with the separator sheet sandwiched between them.

[0013] When swelling of the electrode assembly 10 generates stress in the radial direction, the stress is concentrated in the portion 14 where the number of turns of the electrode sheet is small. This is because the strength of the portion 14 where the number of turns of the electrode sheet is small is relatively weak. As a result, the cavity 15 in the portion 14 indicated by the dotted line cannot maintain its shape and begins to collapse. Furthermore, as the swelling of the electrode assembly 10 progresses further, the collapse of the cavity 15 propagates to neighboring regions, further accelerating the collapse of the cavity 15.

[0014] The collapse of the cavity 15 forms a minute gap between the first electrode sheet 11 and the second electrode sheet 12 in the core of the electrode assembly 10. Because electrochemical reactions do not occur in the gap, the performance of the cylindrical battery suddenly deteriorates. This problem becomes more likely as the form factor increases. This is because the diameter of the cavity 15 also increases as the diameter of the winding means used to wind the electrode assembly 10 increases. As the diameter of the cavity 15 increases, the region of the electrode assembly 10 near the cavity 15 becomes more vulnerable to stress.

[0015] Furthermore, if the cavity 15 collapses, the separator sheet 13 interposed between the first electrode sheet 11 and the second electrode sheet 12 may be torn, potentially causing an internal short circuit between the first electrode sheet 11 and the second electrode sheet 12. At the point of the internal short circuit, a large amount of current flows and the temperature rises rapidly. Therefore, an internal short circuit caused by swelling of the electrode assembly 10 is a major cause of fire in cylindrical batteries. Summary of the Invention [Problem to be solved by the invention]

[0016] The present invention has been devised in light of the background of the prior art as described above, and has an object to provide an electrode assembly having an improved core structure that can resist swelling while maintaining the core cavity intact, and a cylindrical battery including the same.

[0017] Another technical object of the present invention is to provide an electrode assembly equipped with a wireless sensor means capable of detecting in advance signs of swelling to the extent that the cavity of the core collapses, and a cylindrical battery including the same.

[0018] Another technical object of the present invention is to provide an electrode assembly equipped with a wireless sensor means capable of detecting in advance signs of a sudden rise in the temperature of the electrode assembly core due to an internal short circuit or the like, and a cylindrical battery including the same.

[0019] It is yet another technical object of the present invention to provide a system capable of remotely monitoring the pressure and / or temperature of a region near the core of a cylindrical battery. [Means for solving the problem]

[0020] The electrode assembly according to the present invention for solving the above technical problems is an electrode assembly in which a first electrode sheet, a second electrode sheet, and a separator sheet interposed therebetween are wound in one direction, and is characterized in that a cavity is provided along a central winding axis of the electrode assembly, and a mesh-like tubular support is disposed along the longitudinal direction of the cavity.

[0021] Preferably, the separator sheet includes a first separator sheet and a second separator sheet, and the first separator sheet, the second electrode sheet, the second separator sheet, and the first electrode sheet may be stacked in this order and rolled up in one direction.

[0022] Preferably, the braided tubular support may comprise a structure of wires and / or straps forming a braided tube.

[0023] In one aspect, the braided tubular support may be a stent support.

[0024] Preferably, the braided tubular support may be radially and / or longitudinally stretchable.

[0025] In one aspect, a gap may be formed between the mesh tubular support and the inner wall of the cavity.

[0026] In another aspect, wireless sensors may be attached to the braided tubular support.

[0027] In one example, the wireless sensor is a wireless pressure sensor, and the wireless pressure sensor may be disposed at one or more points on an exterior or interior surface of the braided tubular support.

[0028] In another example, the wireless sensor is a wireless temperature sensor, and the wireless temperature sensor may be disposed at one or more points on an exterior or interior surface of the braided tubular support.

[0029] A cylindrical battery according to another aspect of the present invention for solving the technical problems may include an electrode assembly in which a first electrode sheet, a second electrode sheet, and a separator sheet interposed therebetween are wound in one direction, the electrode assembly having a cavity along a central axis of the winding; a mesh-like tubular support disposed along the length of the cavity; a case in which the electrode assembly is housed and which has an opening on one side; and a cap assembly insulatively coupled to the opening of the case.

[0030] Preferably, the separator sheet includes a first separator sheet and a second separator sheet, and the first separator sheet, the second electrode sheet, the second separator sheet, and the first electrode sheet may be stacked in this order and rolled up in one direction.

[0031] Preferably, the braided tubular support may comprise a structure of wires and / or straps forming a braided tube.

[0032] In one aspect, the braided tubular support may be a stent support.

[0033] Preferably, the braided tubular support may be radially and / or longitudinally stretchable.

[0034] In one aspect, a gap may be formed between the mesh tubular support and the inner wall of the cavity.

[0035] In another aspect, wireless sensors may be attached to the braided tubular support.

[0036] In one example, the wireless sensor is a wireless pressure sensor, and the wireless pressure sensor may be disposed at one or more points on an exterior or interior surface of the braided tubular support.

[0037] In another example, the wireless sensor is a wireless temperature sensor, and the wireless temperature sensor may be disposed at one or more points on an exterior or interior surface of the braided tubular support.

[0038] In another aspect, one end of the mesh tubular support may be secured to the cap assembly or the bottom surface of the case via a securing tab.

[0039] In yet another aspect, one end of the braided tubular support may be fixed to the inner wall of the cavity via a fixing sleeve.

[0040] The system for solving the technical problem may include a cylindrical battery including: an electrode assembly in which a first electrode sheet, a second electrode sheet, and a separator sheet interposed therebetween are wound in one direction, the electrode assembly having a cavity along a central axis of winding; a mesh-like tubular support disposed along the longitudinal direction of the cavity; a case in which the electrode assembly is housed and which has an opening provided on one side; and a cap assembly insulatively coupled to the opening of the case; a wireless sensor attached to the mesh-like tubular support and wirelessly transmitting a pressure sensing value or a temperature sensing value; and a detection device that receives the pressure sensing value or the temperature sensing value from the wireless sensor and monitors the pressure or temperature at a point where the wireless sensor is disposed.

[0041] When the pressure sensing value or the temperature sensing value exceeds a preset threshold, the system controls a switch disposed in a line through which a charging current or a discharging current of the cylindrical battery flows to interrupt charging or discharging of the cylindrical battery, or The device may be configured to generate a warning message indicating that there is an abnormality inside the cylindrical battery and output it via a display. [Effects of the Invention]

[0042] According to one aspect of the present invention, a mesh-shaped tubular support is inserted into a cavity of an electrode assembly used in a cylindrical battery to reinforce the core rigidity, thereby preventing the cavity from collapsing even if swelling occurs in the electrode assembly, thereby preventing an increase in internal resistance or an internal short circuit in the core of the electrode assembly.

[0043] According to another aspect of the present invention, by attaching a wireless pressure sensor to a mesh-like tubular support, it is possible to detect signs of swelling to the extent that the cavity of the electrode assembly may collapse in advance. Furthermore, if the cavity actually begins to collapse, the degree of stress applied to that point and the location of that point can be accurately detected.

[0044] According to another aspect of the present invention, a wireless temperature sensor is attached to the mesh-shaped tubular support, thereby making it possible to detect signs of overheating in the cavity of the electrode assembly in advance, and when overheating occurs, the temperature and location of the point can be accurately detected.

[0045] The following drawings attached to this specification illustrate preferred embodiments of the present invention and, together with the detailed description of the invention described below, serve to further understand the technical concept of the present invention, and therefore the present invention should not be interpreted as being limited to only the matters depicted in such drawings. [Brief explanation of the drawings]

[0046] [Figure 1] 10 is an exemplary diagram showing how the cavity in the core collapses when swelling occurs in an electrode assembly according to the prior art. [Figure 2] 1 is a radial cross-sectional view of an electrode assembly according to an embodiment of the present invention; [Figure 3] 4A to 4C are process diagrams illustrating a process of manufacturing an electrode assembly according to an embodiment of the present invention. [Figure 4] 1 is a longitudinal cross-sectional view of an electrode assembly according to an embodiment of the present invention; [Figure 5] 1(a) to 1(i) are diagrams illustrating various configurations of stent supports according to embodiments of the present invention. [Figure 6a] 1 is a cross-sectional view of a cylindrical battery including an electrode assembly according to an embodiment of the present invention. [Figure 6b] FIG. 2 is an exploded perspective view of a cap assembly according to an embodiment of the present invention. [Figure 7] 1 is a block diagram illustrating a configuration of a wireless pressure sensor and a detection device according to an embodiment of the present invention. [Figure 8] 1 is a block diagram illustrating a configuration of a wireless temperature sensor and a detection device according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0047] Hereinafter, preferred embodiments of the present invention will be described in more detail with reference to the accompanying drawings. The embodiments of the present invention are provided to more completely explain the present invention to those skilled in the art, and the following embodiments can be modified into various other forms, and the scope of the present invention is not limited to the following embodiments. Rather, these embodiments are provided to make the disclosure of the present invention more complete and complete, and to fully convey the concept of the present invention to those skilled in the art.

[0048] In the following drawings, the thickness and size of each layer have been exaggerated for ease of explanation and clarity, and the same reference numerals refer to the same components throughout the drawings. As used herein, the term "and / or" includes any one of the listed items and any combination of one or more of the listed items. Note that the terms "coupled" and "connected" as used herein do not only refer to cases where one component is directly coupled or connected to another component, but also to cases where another component is indirectly coupled or connected to another component with another component interposed therebetween.

[0049] The terms used in this specification are merely used to describe particular embodiments and are not intended to limit the present invention. As used in this specification, the singular term "a," "an," or "the" includes the plural term unless otherwise indicated in the specification or clearly contradicted by the context. Furthermore, when used in this specification, "comprise" and / or "comprising" should be understood to specify only the presence of the stated shapes, numbers, steps, operations, components, elements, and / or combinations thereof, and not to preclude the possibility of the presence or addition of one or more other shapes, numbers, steps, operations, components, elements, and / or combinations thereof.

[0050] In this specification, terms such as "first" and "second" are used to describe various members, components, regions, layers, and / or portions, but it is clear that these members, components, regions, layers, and / or portions should not be limited by these terms. These terms are used only to distinguish one member, component, region, layer, or portion from other members, components, regions, layers, or portions. Therefore, a first member, component, region, layer, or portion described in detail below may refer to a second member, component, region, layer, or portion without departing from the teachings of the present invention.

[0051] Spatial terms and phrases such as "beneath," "below," "lower," "above," "upper," and the like are used to facilitate understanding of one component or feature in relation to another component or feature shown in the drawings. These spatial terms and phrases are used to facilitate understanding of the present invention in accordance with various process or use states of the present invention, and are not intended to limit the present invention. For example, if a component or feature in the drawings is turned over, a component described as "beneath" or "below" would become "upper" or "above." Therefore, "below" is a concept that encompasses "upper" or "below."

[0052] Fig. 2 is a radial cross-sectional view of an electrode assembly 100 according to an embodiment of the present invention, and Fig. 3 is a process diagram showing a process for fabricating the electrode assembly 100 according to an embodiment of the present invention. Fig. 3(a) is a cross-sectional view of the part, and Fig. 3(b) is a plan view of the part. Fig. 4 is a longitudinal cross-sectional view of the electrode assembly 100 according to an embodiment of the present invention.

[0053] Referring to FIG. 2, an electrode assembly 100 according to the present invention includes a first electrode sheet 110 having a first polarity, a second electrode sheet 120 having a second polarity, and a separator sheet 130.

[0054] The first polarity and the second polarity are opposite polarities. In one example, the first polarity is negative and the second polarity is positive. In another example, the first polarity can be positive and the second polarity can be negative.

[0055] Referring to FIG. 3, the electrode assembly 100 can be fabricated by stacking a first separator sheet 130a, a second electrode sheet 120, a second separator sheet 130b, and a first electrode sheet 110 in this order, and continuously winding the sheet stack in one direction.

[0056] After the four sheets are wound, the wound state of the sheets can be fixed using a hot press process that applies heat and pressure to the electrode assembly 100. Alternatively, to fix the wound state, tape can be attached to the last wound portion of the first separator sheet 130a.

[0057] The second separator sheet 130b serves to electrically separate the first electrode sheet 110 and the second electrode sheet 120. The first electrode sheet 110, the second separator sheet 130b, and the second electrode sheet 120 constitute a cell that can be electrochemically charged or discharged. The first separator sheet 130a is used as a film for winding up the cell.

[0058] The first and second separator sheets 130a and 130b are made of insulating porous films. In one example, the porous films may be polyolefin-based porous films. A ceramic particle coating layer may be provided on the surface of the porous films.

[0059] The first and second separator sheets 130a, 130b may be made of the same material or different materials. The ceramic particle coating may be formed only on the second separator sheet 130b. Even if the first and second separator sheets 130a, 130b are made of the same material, they may have different melting points.

[0060] The first electrode sheet 110 has a structure in which one or both sides of a current collector 110a are coated with an active material 110b of a first polarity. Similarly, the second electrode sheet 120 has a structure in which one or both sides of a current collector 120a are coated with an active material 120b of a second polarity.

[0061] The positive electrode current collector may be made of stainless steel, nickel, titanium, plastic carbon, or aluminum or stainless steel whose surface has been treated with carbon, nickel, titanium, silver, or the like.

[0062] The positive electrode active material can be either a lithium-containing transition metal oxide or a lithium chalcogenide compound. Typical examples include LiCoO2, LiNiO2, LiMnO2, LiMn2O4, LiFePO4, or Li 1+z Ni 1-x-y Co x M y Metal oxides such as O2 (0≦x≦1, 0≦y≦1, 0≦x+y≦1, 0≦z≦1, M is a metal such as Al, Sr, Mg, La, or Mn) can be used.

[0063] As the negative electrode current collector, stainless steel, aluminum, nickel, titanium, plastic carbon, copper, or stainless steel whose surface has been treated with carbon, nickel, titanium, silver, or the like can be used, and an aluminum-cadmium alloy can also be used.

[0064] As the negative electrode active material, carbon materials such as crystalline carbon, amorphous carbon, carbon composites, and carbon fibers, lithium metal, lithium alloys, silicon, and silicon alloys can be used.

[0065] Meanwhile, since the present invention is characterized by the structure of the electrode assembly 100, there is no limitation on the types of materials constituting the positive and negative electrode current collectors, the positive and negative electrode active materials, and the separator.

[0066] Referring to FIG. 3, the first electrode sheet 110 has an uncoated portion 111 in a predetermined region. The uncoated portion 111 is a portion that is not coated with an active material. The first electrode sheet 110 also includes a first tab 112 attached to the uncoated portion 111. The first tab 112 may be ultrasonically welded to the uncoated portion 111. The uncoated portion 111 may be formed at one end of the current collector, as shown. In another example, the uncoated portion 111 may be formed in the middle of the active material layer 110b.

[0067] The second electrode sheet 120 has an uncoated portion 121 in a predetermined region. The second electrode sheet 120 also includes a second tab 122 attached to the uncoated portion 121. The second tab 122 may be ultrasonically welded to the uncoated portion 121. The uncoated portion 121 may be formed in the middle of the active material layer 120b as shown. In another example, the uncoated portion 121 may be formed at one end of the current collector 120a.

[0068] 4, a cavity 140 is formed in the core of the electrode assembly 100 according to an embodiment of the present invention. The cavity 140 is formed when the winding means (bobbin) used in the winding process of the electrode assembly 100 is removed.

[0069] Preferably, the cavity 140 of the electrode assembly 100 is provided with a mesh tubular support 150 extending along its length.

[0070] The mesh tubular support 150 has a structure in which wires and / or straps form a mesh tube.

[0071] Preferably, the meshed tubular support 150 may be a stent support. A stent is a medical device that is inserted into narrowed blood vessels or the digestive tract. A stent has a structure in which wires and / or straps form a mesh tube.

[0072] 5 illustrates various configurations of stent supports according to embodiments of the present invention. In each stent configuration, the shape, thickness, width, pitch, etc. of the wires and / or straps can be determined using a finite element analysis tool, taking into account the required stiffness of the braided tubular support 150.

[0073] It will be obvious to those skilled in the art to which the present invention pertains that various stent structures known in the art, in addition to those shown in Figure 5, can be applied to the structure of the reticulated tubular support 150.

[0074] The mesh-shaped tubular support 150 is elastically expandable in the radial and / or longitudinal directions. Therefore, when inserted into the cavity 140 of the electrode assembly 100, the mesh-shaped tubular support 150 uses elastic strain to absorb stress generated around the cavity 140 when swelling occurs in the electrode assembly 100, thereby preventing the cavity 140 from collapsing. Furthermore, the mesh-shaped tubular support 150 is not only hollow inside, but also has numerous openings formed in its wall. Therefore, the mesh-shaped tubular support 150 does not hinder the flow of electrolyte during the process of impregnating the electrode assembly 100 with the electrolyte, and does not reduce the energy density of the cylindrical battery.

[0075] The material of the wires and / or straps can be appropriately selected taking into consideration the rigidity of the mesh tubular support 150. The material of the wires and / or straps can be selected from a single metal, an alloy, or a plastic. In a preferred example, the material of the wires and / or straps can be stainless steel or a shape memory alloy.

[0076] Preferably, the braided tubular support 150 may be fabricated to have a contracted radius and length, and then deployed within the cavity 140 while expanding radially and longitudinally. Such deployment methods are well known in the field of stent technology. Existing stent deployment methods can be used to deploy the braided tubular support 150 in substantially the same manner.

[0077] FIG. 6a is a cross-sectional view of a cylindrical battery 200 including an electrode assembly 100 according to an embodiment of the present invention, and FIG. 6b is an exploded perspective view of a cap assembly 220 according to an embodiment of the present invention.

[0078] Referring to Figures 6a and 6b, a cylindrical battery 200 includes an electrode assembly 100, a case 210 that houses the electrode assembly 100 and has an opening on one side, and a cap assembly 220 that seals the opening of the case 210.

[0079] The case 210 includes a circular bottom 211 and a sidewall 212 extending a certain length upward from the bottom 211. During the manufacturing process of the cylindrical battery 200, the top of the case 210 may be open so that the electrode assembly 100 can be inserted into the case 210 together with the electrolyte during the assembly process.

[0080] The case 210 may be made of, but is not limited to, steel, a steel alloy, aluminum, an aluminum alloy, or an equivalent material. In addition, the case 210 may have a beading part 213 recessed inward at its lower part relative to the cap assembly 220 to prevent the electrode assembly 100 from slipping out, and a crimping part 214 bent inward at its upper part.

[0081] The electrolyte is an organic liquid containing a salt that allows lithium ions to move between the electrodes constituting the electrode assembly 100, and may include a non-aqueous organic electrolyte that is a mixture of a lithium salt such as LiPF, LiBF, or LiClO and a high-purity organic solvent, but the present invention is not limited thereto.

[0082] The cap assembly 220 may include a cap cover 222 having one or more through holes 221 formed therein, a safety plate 223 fixed to the lower part of the cap cover 222 so as to wrap around the peripheral portion of the cap cover 222 and having a vent notch formed on the upper surface thereof, a connecting ring 224 disposed on the lower part of the safety plate 223, a connecting plate 225 coupled to the connecting ring 224, and an insulating gasket 226 that insulates the cap cover 222, the safety plate 223, the connecting ring 224, and the connecting plate 225 from the side wall portion 212 of the case 210.

[0083] The portions where the cap cover 222, the safety plate 223, the connecting ring 224 and the connection plate 225 come into contact with one another can be electrically connected to one another by selectively using means such as welding or adhesive.

[0084] The cap cover 222, the safety plate 223, the connecting ring 224 and the connecting plate 225 may be made of steel, a steel alloy, aluminum, an aluminum alloy or the equivalent, but the materials are not limited thereto.

[0085] An upper insulating plate 230 and a lower insulating plate 240 are respectively coupled to the upper and lower portions of the electrode assembly 100. The upper insulating plate 230 and the lower insulating plate 240 are made of an insulating material.

[0086] The upper insulating plate 230 and the lower insulating plate 240 may be made of a polymer resin such as polyethylene, polypropylene, polyethylene terephthalate (PET), polytetrafluoroethylene (PTFE), polyimide, etc., but the material is not limited thereto.

[0087] In the electrode assembly 100, the first tab 112 of the first electrode sheet 110 extends downward through an opening formed in the lower insulating plate 240, and then extends parallel to the inner surface of the bottom 211 of the case 210. The end of the first tab 112 is welded to the inner surface of the bottom 211.

[0088] In the electrode assembly 100, the second tab 122 of the second electrode sheet 120 extends upward through an opening formed in the upper insulating plate 230 and is then bent toward the connecting plate (connecting plate 225) of the cap assembly 220. An end of the second tab 122 is fixed to the connecting plate (connecting plate 225) by welding.

[0089] The mesh tubular support 150 is inserted into a cavity 140 formed in the core of the electrode assembly 100. In one example, the outer diameter of the mesh tubular support 150 is smaller than the diameter of the cavity 140 of the electrode assembly 100. In this case, a gap may be formed between the surface of the mesh tubular support 150 and the inner wall of the cavity 140. In another example, the outer diameter of the mesh tubular support 150 corresponds to the diameter of the cavity 140 of the electrode assembly 100.

[0090] To secure the mesh tubular support 150, the upper end of the mesh tubular support 150 may be secured to the lower surface of the connection plate (connection plate 225) via a securing tab 250. One end of the securing tab 250 is welded to the inner wall or outer wall of the upper end of the mesh tubular support 150. The other end of the securing tab 250 protrudes upward through an opening formed in the upper insulating plate 230 and extends to the connection plate (connection plate 225). The other end of the securing tab 250 may be bent parallel to the connection plate (connection plate 225) and then firmly welded to the lower surface of the fixing plate 255. In this case, the welding position of the fixing tab 250 may be appropriately selected so as not to cause interference with the second tab 122.

[0091] The securing tabs 250 may be made from steel, steel alloy, aluminum, aluminum alloy, or equivalents, but the material is not intended to be limiting.

[0092] A fixing sleeve 260 may be interposed between the lower end of the mesh tubular support 150 and the inner wall of the cavity 140 of the electrode assembly 100. Preferably, the fixing sleeve 260 has a tubular shape, and the thickness of the wall of the fixing sleeve 260 corresponds to the gap between the mesh tubular support 150 and the cavity 140.

[0093] The fixing sleeve 260 is made of an insulating material. In one example, the fixing sleeve 260 may be made of a polymer resin such as polyethylene, polypropylene, polyethylene terephthalate (PET), polytetrafluoroethylene (PTFE), or polyimide, but the material is not limited thereto.

[0094] Unlike the illustration, the lower end of the mesh tubular support 150 may be fixed using a fixing tab (not shown) without using the fixing sleeve 260. In this case, one end of the fixing tab is welded to the outer wall or inner wall of the lower end of the mesh tubular support 150. The other end of the fixing tab may extend to the inner surface of the bottom 211 through an opening in the lower insulating plate 240. Furthermore, the other end of the fixing tab may be welded and fixed to the inner surface of the bottom 211 while avoiding interference with the first tab 112. When a fixing tab is used to fix the lower end of the mesh tubular support 150, the upper end of the mesh tubular support 150 may be fixed using a fixing sleeve (not shown) without using the fixing tab 250.

[0095] The method for fixing the upper and lower ends of the mesh-like tubular support 150 may be the same or different. In addition to the fixing tabs and fixing sleeves described above, the upper and lower ends of the mesh-like tubular support 150 may be fixed by selectively using various known structures.

[0096] According to another aspect, at least one wireless sensor 270 may be attached to the surface of the braided tubular support 150. The wireless sensors 270 may be disposed at multiple points along the length of the braided tubular support 150. The wireless sensors 270 are preferably of a miniature type.

[0097] In the drawings, the wireless sensors 270 are shown as being disposed at the top, middle, and bottom of the mesh tubular support 150. However, the number of locations at which the wireless sensors 270 are disposed can be increased or decreased.

[0098] In one example, the wireless sensor 270 may be a wireless pressure sensor 300 as shown in Fig. 7. The wireless pressure sensor 300 is a device that senses contact pressure when an external object comes into contact with the sensor and wirelessly transmits the pressure sensing value.

[0099] Preferably, the wireless pressure sensor 300 may include a wireless charging unit 310 having a magnetoelectric composite (ME composite) that generates a voltage in response to an externally applied magnetic field, and a pressure sensor unit 330 that is driven by the driving voltage generated in the wireless charging unit 310 to sense pressure and wirelessly transmits the pressure sensing value to the outside via an antenna 320.

[0100] The wireless charging unit 310 may include a magnetostrictive material that converts magnetic energy associated with an external magnetic field into strain energy, and a piezoelectric material that is combined with the magnetostrictive material and generates a voltage using the strain energy.

[0101] When a swelling phenomenon occurs in the electrode assembly 100, the wireless pressure sensor 300 detects that the inner wall of the cavity 140 is distorted due to stress and can wirelessly transmit a pressure sensing value to the outside. That is, when the inner wall of the cavity 140 is distorted and comes into contact with the wireless pressure sensor 300, the wireless pressure sensor 300 can wirelessly transmit a pressure sensing value corresponding to the strength of the contact.

[0102] A detection device 400 may be provided to receive the pressure sensing value. By detecting the pressure sensing value using the detection device 400, it is possible to detect in advance that there is a sign that the cavity 140 of the electrode assembly 100 is about to collapse due to a swelling phenomenon.

[0103] When there are multiple wireless pressure sensors 300, each wireless pressure sensor 300 may further transmit a location ID. In this case, the detection device 400 may detect a pressure sensing value for each location of the wireless pressure sensor 300, thereby accurately identifying the location where there is a sign of collapse of the cavity 140.

[0104] The detection device 400 can periodically apply a magnetic field to the wireless pressure sensor 300 to operate the wireless pressure sensor 300. Then, a driving voltage is generated in the wireless charging unit 310 of the wireless pressure sensor 300 and applied to the pressure sensor unit 330. Then, the pressure sensor unit 330 can generate a pressure sensing value in response to contact with an external object and wirelessly transmit the pressure sensing value to the detection device 400 via the antenna 320.

[0105] The wireless pressure sensors 300 may be disposed at multiple points along the vertical direction of the mesh-like tubular support 150. In this case, it is possible to accurately detect at what position the cavity shows signs of collapse.

[0106] When the wireless pressure sensor 300 is attached to the outer wall of the mesh tubular support 150, a gap is preferably formed between the mesh tubular support 150 and the inner wall of the cavity 140 of the electrode assembly 100. The gap is preferably adjusted to a level that prevents the wireless pressure sensor from directly contacting the inner wall of the cavity 140.

[0107] When the wireless pressure sensor 300 is attached to the inner wall of the mesh tubular support 150, there may be no gap between the mesh tubular support 150 and the inner wall of the cavity 140 of the electrode assembly 100. In this case, stress generated when the cavity 140 collapses will distort the wire and / or strap on which the wireless pressure sensor 300 is disposed, and pressure sensing can be performed in the process.

[0108] In another example, the wireless sensor may be a wireless temperature sensor 500 as shown in Fig. 8. The wireless temperature sensor 500 is a device that senses the temperature at the point where the sensor is installed and transmits the sensed temperature value wirelessly.

[0109] Preferably, the wireless temperature sensor 500 may include a wireless charging unit 510 having a magnetoelectric composite (ME composite) that generates a voltage in response to an externally applied magnetic field, and a temperature sensor unit 530 that is driven by the driving voltage generated in the wireless charging unit 510 to sense temperature and wirelessly transmit the sensed temperature value via the antenna 520. The temperature sensor unit 530 may include a micro-thermocouple (thermostat).

[0110] The wireless charging unit 510 may include a magnetostrictive material that converts magnetic energy associated with an external magnetic field into strain energy, and a piezoelectric material that is combined with the magnetostrictive material and generates a voltage using the strain energy.

[0111] By detecting the temperature sensing value in the detection device 400, it is possible to detect in advance the possibility of a sudden temperature rise occurring in the cavity 140 of the electrode assembly 100.

[0112] The detection device 400 can periodically apply a magnetic field to the wireless temperature sensor 500 to operate the wireless temperature sensor 500. Then, a voltage is generated in the wireless charging unit 510 of the wireless temperature sensor 500 and applied to the temperature sensor unit 530. Then, the temperature sensor unit 530 can sense the temperature at the sensor installation point, generate a temperature sensing value, and wirelessly transmit the temperature sensing value to the detection device 400 via the antenna 520.

[0113] The wireless temperature sensors 500 may be disposed at multiple points along the vertical direction of the mesh-like tubular support 150. When multiple wireless temperature sensors 500 are provided, each wireless temperature sensor 500 may further transmit a location ID. In this case, the detection device 400 can detect the temperature sensing value for each location of the wireless temperature sensor 500, thereby accurately identifying the location within the cavity 140 where there is a sign of overheating.

[0114] Overheating of the cavity 140 occurs when an internal short circuit occurs near the cavity due to swelling of the electrode assembly 100. Therefore, by monitoring the temperature of the cavity 140 using the wireless temperature sensor 500, it is possible to accurately detect at what point in the cavity 140 an internal short circuit has occurred.

[0115] The cylindrical battery 200, the wireless sensors (wireless pressure sensor 300, wireless temperature sensor 500), and the detection device 400 described above may constitute a system according to the present invention. The detection device 400 may be included in a battery management unit 600 that controls charging and discharging of the cylindrical battery 200. The battery management unit 600 may be included in a load that receives power from the cylindrical battery 200. In this case, the battery management unit 600 may monitor the pressure and / or temperature sensed values detected by the detection device 400. Furthermore, the battery management unit 600 may interrupt charging or discharging of the cylindrical battery 200 if the pressure and / or temperature sensed values exceed a preset threshold. To this end, the battery management unit 600 may turn off a switch disposed in a line through which the charging or discharging current flows. Furthermore, the battery management unit 600 may generate a warning message indicating an abnormality inside the cylindrical battery 200 and output the message via a display. The display may be disposed in a device that receives energy from the cylindrical battery 200. In one example, if the device is an electric vehicle, the display may be an integrated display disposed in the instrument panel or dashboard.

[0116] The present invention can be effectively used to analyze the behavior of stress occurring in the core of an electrode assembly during the design stage of the electrode assembly and a cylindrical battery including the electrode assembly, and to analyze the cause of an internal short circuit.

[0117] Furthermore, the present invention can be utilized to detect in advance the collapse of cavities that occur in the core portion of the electrode assembly or the signs of overheating that accompany an internal short circuit when the cylindrical battery is actually used.

[0118] According to one aspect of the present invention, a mesh-shaped tubular support is inserted into a cavity of an electrode assembly used in a cylindrical battery to reinforce the core rigidity, thereby preventing the cavity from collapsing even if swelling occurs in the electrode assembly, thereby preventing an increase in internal resistance or an internal short circuit in the core of the electrode assembly.

[0119] According to another aspect of the present invention, by attaching a wireless pressure sensor to a mesh-like tubular support, it is possible to detect signs of swelling to the extent that the cavity of the electrode assembly may collapse in advance. Furthermore, if the cavity actually begins to collapse, the degree of stress applied to that point and the location of that point can be accurately detected.

[0120] According to another aspect of the present invention, a wireless temperature sensor is attached to the mesh-shaped tubular support, thereby making it possible to detect signs of overheating in the cavity of the electrode assembly in advance, and when overheating occurs, the temperature and location of the point can be accurately detected.

[0121] Although the present invention has been described above using limited embodiments and drawings, the present invention is not limited to these, and it goes without saying that various modifications and variations can be made by a person having ordinary knowledge in the technical field to which the present invention pertains within the technical spirit of the present invention and the scope of equivalents of the claims.

Claims

1. An electrode assembly in which a first electrode sheet, a second electrode sheet, and a separator sheet interposed therebetween are wound in one direction, A cavity is provided along the winding central axis of the electrode assembly, A mesh-like tubular support is disposed along the longitudinal direction of the cavity, a wireless pressure sensor attached to the braided tubular support; An electrode assembly, wherein the wireless pressure sensor is an element disposed at at least one point on the outer or inner surface of the mesh-like tubular support and senses the contact pressure applied by the inner wall of the cavity due to distortion of the cavity.

2. The electrode assembly of claim 1 , wherein the braided tubular support comprises a structure in which wires and / or straps form a braided tube.

3. 3. The electrode assembly according to claim 2, wherein the braided tubular support is a stent support.

4. The electrode assembly according to claim 1 , wherein the reticulated tubular support is extensible in the radial and / or longitudinal directions.

5. 2. The electrode assembly of claim 1, wherein a gap is formed between the braided tubular support and the inner wall of the cavity. 。

6. an electrode assembly in which a first electrode sheet, a second electrode sheet, and a separator sheet interposed therebetween are wound in one direction, the electrode assembly having a cavity along a winding central axis; a mesh-like tubular support disposed along the longitudinal direction of the cavity; a case in which the electrode assembly is housed and which has an opening on one side; a cap assembly for sealing the opening of the case; a wireless pressure sensor attached to the mesh tubular support; Including, A cylindrical battery, wherein the wireless pressure sensor is disposed at at least one point on the outer or inner surface of the mesh-like tubular support and is an element that senses the contact pressure applied by the inner wall of the cavity due to distortion of the cavity.

7. 7. The cylindrical battery of claim 6, wherein the braided tubular support comprises a structure of wires and / or straps forming a braided tube.

8. 8. The cylindrical battery according to claim 7, wherein the reticulated tubular support is a stent support.

9. 7. The cylindrical battery according to claim 6, wherein the reticulated tubular support is extensible in the radial direction and / or the longitudinal direction.

10. 8. The cylindrical battery according to claim 7, wherein a gap is formed between the reticulated tubular support and the inner wall of the cavity.

11. 7. The cylindrical battery according to claim 6, further comprising a fixing tab for fixing one end of said mesh tubular support to said cap assembly or the bottom surface of said case.

12. 7. The cylindrical battery of claim 6, further comprising a fixing sleeve for fixing one end of said braided tubular support to the inner wall of said cavity.

13. a cylindrical battery including: an electrode assembly in which a first electrode sheet, a second electrode sheet, and a separator sheet interposed therebetween are wound in one direction, the electrode assembly having a cavity along a central axis of winding; a mesh-like tubular support disposed along the longitudinal direction of the cavity; a case in which the electrode assembly is housed and which has an open portion on one side; and a cap assembly for sealing the open portion of the case; a wireless sensor attached to the mesh-shaped tubular support and configured to wirelessly transmit a pressure sensing value; a detection device that receives the pressure sensing value from the wireless sensor and monitors the pressure at the point where the wireless sensor is disposed; Including, The system, wherein the wireless sensor is disposed at at least one point on the outer or inner surface of the mesh-like tubular support and is an element that senses the contact pressure applied by the inner wall of the cavity due to distortion of the cavity.

14. When the pressure sensing value exceeds a preset threshold, the system controls a switch disposed in a line through which a charging current or a discharging current of the cylindrical battery flows to interrupt charging or discharging of the cylindrical battery, or The system according to claim 13, wherein a warning message indicating that there is an abnormality inside the cylindrical battery is generated and output via a display.

15. An electrode assembly in which a first electrode sheet, a second electrode sheet, and a separator sheet interposed therebetween are wound in one direction, A cavity is provided along the winding central axis of the electrode assembly, A mesh-like tubular support is disposed along the longitudinal direction of the cavity, An electrode assembly wherein the outer diameter of the mesh tubular support is smaller than the diameter of the cavity of the electrode assembly.

16. an electrode assembly in which a first electrode sheet, a second electrode sheet, and a separator sheet interposed therebetween are wound in one direction, the electrode assembly having a cavity along a winding central axis; a mesh-like tubular support disposed along the longitudinal direction of the cavity; a case in which the electrode assembly is housed and which has an opening on one side; a cap assembly for sealing the opening of the case; Including, A cylindrical battery, wherein the outer diameter of the reticulated tubular support is smaller than the diameter of the cavity of the electrode assembly.

17. a cylindrical battery including: an electrode assembly in which a first electrode sheet, a second electrode sheet, and a separator sheet interposed therebetween are wound in one direction, the electrode assembly having a cavity along a central axis of winding; a mesh-like tubular support disposed along the longitudinal direction of the cavity; a case in which the electrode assembly is housed and which has an open portion on one side; and a cap assembly for sealing the open portion of the case, wherein the outer diameter of the mesh-like tubular support is smaller than the diameter of the cavity of the electrode assembly; a wireless sensor attached to the mesh-shaped tubular support and configured to wirelessly transmit a pressure sensing value or a temperature sensing value; a detection device that receives the pressure sensing value or the temperature sensing value from the wireless sensor and monitors the pressure or temperature at the point where the wireless sensor is installed; Including, the system.

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