Electrode plate, electrode assembly, and secondary battery including the same

Abstract

To provide an electrode plate, an electrode assembly, and a secondary battery including the same that can realize electrical conduction between adjacent electrode plates.SOLUTION: An electrode plate according to the present invention includes a base layer, a current collecting layer including a first conductive layer and a second conductive layer located on the upper and lower surfaces of the base layer, respectively, and an electrode layer located on at least one surface of the current collecting layer, and a portion of the first conductive layer and a portion of the second conductive layer are extended beyond and connected to the base layer.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to an electrode plate, an electrode assembly, and a secondary battery including the same.

Background Art

[0002] Although rechargeable batteries are manufactured in various shapes, among them, a pouch battery includes an electrode assembly in which an insulator separator is interposed between a positive electrode plate and a negative electrode plate, and a thin flexible pouch in which the electrode assembly is incorporated. At this time, the pouch houses the electrode assembly in an inner space.

[0003] The electrode assembly of a secondary battery is broadly classified into a winding type and a stacking type according to its structure. The stacking type has good structural safety and excellent space utilization, and is widely applied to small, medium-sized, and large-sized batteries. The stacking type secondary battery is formed by laminating a plurality of electrode plates and separator membranes.

[0004] The current collectors applied to the electrodes of a secondary battery, that is, the positive electrode and the negative electrode, may be usually thin films of electrically conductive copper, aluminum, Ni, SUS, etc. For example, in the case of a commercialized lithium ion battery, a copper foil current collector is used for the negative electrode and an aluminum foil current collector is used for the positive electrode.

[0005] Recently, in order to reduce the manufacturing cost and weight of secondary batteries, instead of manufacturing the entire current collector layer with copper or aluminum, a current collector layer in which metal films are coated on both sides of a resin is also applied.

[0006] In a resin-metal composite base material, metal films are located on both sides of a resin sheet, and there is a problem that since the resin has low conductivity, the metal films on both sides are not energized with each other.

Summary of the Invention

Problems to be Solved by the Invention

[0007] The present invention is for overcoming the above-described conventional problems, and an object of the present invention is to provide an electrode plate, an electrode assembly, and a secondary battery including the same that can achieve energization between electrode plates adjacent to each other.

[0008] However, the technical problems to be solved by the present invention are not limited to the above-described problems, and other problems not mentioned should be clearly understood by those skilled in the art from the description of the invention described below.

Means for Solving the Problems

[0009] An electrode plate according to an embodiment of the present invention for solving the above technical problems includes a base layer, a current collector layer including a first conductive layer and a second conductive layer respectively located on the upper and lower surfaces of the base layer, and a plate layer located on at least one surface of the current collector layer, wherein a part of the first conductive layer and a part of the second conductive layer are extended and joined from the base layer.

[0010] The base layer may include a body portion and an inclined portion that is integrated with the body portion and whose thickness gradually decreases toward the end.

[0011] The current collector layer includes a current collecting portion on which the plate layer is located on at least one surface, and a plain portion extending from the current collecting portion to the outside, and a part of the first conductive layer and a part of the second conductive layer may further extend from the plain portion and their ends may be joined to each other.

[0012] The base layer may include one or more of polyethylene terephthalate, polyamide, polyimide, polybutylene terephthalate, polyethylene naphthalate, polycarbonate, polyethylene, polypropylene, polyethylene propylene, acrylonitrile-butadiene-styrene copolymer, polyvinyl alcohol, polystyrene, polyvinyl chloride, polyvinylidene fluoride, polytetrafluoroethylene, sodium polystyrene sulfonate, polyacetylene, silicone rubber, polyoxymethylene, polyphenylene ether, polyphenylene sulfide, polyethylene glycol, polysulfur nitride, polyphenylene, polypyrrole, polyaniline, polythiophene, polypyridine, cellulose, starch, protein, epoxy resin, phenol resin, derivatives of the aforementioned materials, cross-linked products of the aforementioned materials, and copolymers of the aforementioned materials.

[0013] The base layer further includes an additive, and the additive may include one or more of a metal material and an inorganic non-metal material.

[0014] The first conductive layer and the second conductive layer may include aluminum.

[0015] The first conductive layer and the second conductive layer may include any one or more of nickel, copper, iron, and alloys containing these.

[0016] The first conductive layer and the second conductive layer may include one or more of a metal material, a carbon-based conductive material, and a conductive polymer material.

[0017] An electrode assembly according to an embodiment of the present invention includes a plurality of electrode plates and a separator, and is an electrode assembly in which a plurality of electrode plates are laminated with the separator interposed therebetween. Each of the plurality of electrode plates includes a base layer, a current collecting layer located on each of the upper and lower surfaces of the base layer and relatively longer than the base layer with a part thereof bonded to each other, and an electrode plate layer disposed on a part of the current collecting layer.

[0018] The base layer may be configured such that the thickness at one end gradually decreases.

[0019] The base layer may include a body portion and an inclined portion that is integral with the body portion and whose thickness gradually decreases toward the end.

[0020] The current collector layers included in each of the plurality of electrode plates may be coupled to each other.

[0021] The current collector layer may include a current collecting portion where the electrode plate layer is located on at least one surface, and a plain portion extending from the current collecting portion to the outside.

[0022] The plurality of electrode plates may include a first electrode plate and a second electrode plate.

[0023] The base layer may include one or more of polyethylene terephthalate, polyamide, polyimide, polybutylene terephthalate, polyethylene naphthalate, polycarbonate, polyethylene, polypropylene, polyethylene propylene, acrylonitrile-butadiene-styrene copolymer, polyvinyl alcohol, polystyrene, polyvinyl chloride, polyvinylidene fluoride, polytetrafluoroethylene, sodium polystyrene sulfonate, polyacetylene, silicone rubber, polyoxymethylene, polyphenylene ether, polyphenylene sulfide, polyethylene glycol, polysulfur nitride, polyphenylene, polypyrrole, polyaniline, polythiophene, polypyridine, cellulose, starch, protein, epoxy resin, phenol resin, derivatives of the foregoing materials, cross-linked products of the foregoing materials, and copolymers of the foregoing materials.

[0024] The base layer may further include an additive, and the additive may include one or more of a metal material and an inorganic non-metallic material.

[0025] The first conductive layer and the second conductive layer may include aluminum.

[0026] The first conductive layer and the second conductive layer may include any one or more of nickel, copper, iron, and alloys containing these materials.

[0027] The first conductive layer and the second conductive layer may include one or more of a metal material, a carbon-based conductive material, and a conductive polymer material.

[0028] The secondary battery according to an embodiment of the present invention includes an electrode assembly and a case that houses the electrode assembly.

Advantages of the Invention

[0029] According to the present invention, in the current collector layer included in the electrode assembly, a part of the first conductive layer and the second conductive layer are bonded to each other. Thereby, a plurality of electrode plates can be electrically connected to each other.

[0030] Thus, the electrode assembly according to an embodiment of the present invention does not need to perform a current conduction process in which a foil is additionally folded and inserted one by one between the electrode plates as in the conventional method. Therefore, not only can the manufacturing time be shortened, but also the manufacturing cost can be reduced.

Brief Description of the Drawings

[0031] The following drawings attached to this specification illustrate preferred embodiments of the present invention and serve to better understand the technical idea of the present invention together with the detailed description of the invention to be described later. Therefore, the present invention should not be construed as being limited only to the matters described in these drawings.

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Embodiments for Carrying Out the Invention

[0032] Hereinafter, with reference to the accompanying drawings, preferred embodiments of the present invention will be described in detail. Prior to this, the terms and words used in this specification and the claims should not be construed as being limited to their ordinary or dictionary meanings. The inventor should be based on the principle that he can appropriately define the concept of the terms in order to explain his own invention in the best way, and should be construed in a meaning and concept consistent with the technical idea of the present invention. Therefore, it should be understood that the embodiments described in this specification and the configurations shown in the drawings are only some of the most preferred embodiments of the present invention, and do not represent all of the technical ideas of the present invention. At the time of this application, there may be various equivalents and modified examples that can replace these.

[0033] Also, as used in this specification, "comprise" and / or "comprising" and / or "include" and / or "including" identify the presence of the recited shape, number, step, action, member, element, and / or group thereof, and do not preclude the presence or addition of one or more other shapes, numbers, actions, members, elements, and / or groups.

[0034] Also, for the understanding of the invention, the accompanying drawings are not illustrated to actual scale, and the dimensions of some components may be exaggerated. Also, the same reference numerals are given to the same components in different embodiments.

[0035] A reference that two objects to be compared are "identical" means that they are "substantially identical". Thus, being substantially identical can include cases where the deviation is regarded as a low level in the art, for example, a deviation within 5%. Also, that any parameter is uniform in a given region means that it is uniform from an average perspective.

[0036] Although terms such as first, second, etc. are used to describe various components, it goes without saying that these components are not limited by these terms. These terms are merely used to distinguish one component from another, and of course, the first component may be the second component unless there is a contrary description.

[0037] Throughout the specification, unless there is a contrary description, each component may be in the singular or plural.

[0038] That any configuration is arranged "above (or, below)" a component or "on (or, under)" a component means that not only is any configuration arranged in contact with the upper surface (or, lower surface) of the said component, but other configurations may also be interposed between the said component and any configuration arranged on (or, under) the said component.

[0039] Also, when a certain component is described as being "on", "connected to", or "coupled to" another component, it should be understood that the said components may be directly connected or joined to each other, but other components may be "interposed" between the components, or each component may be "connected", "coupled", or "joined" through other components.

[0040] As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items. Also, when describing embodiments of the present disclosure, the use of "can also be done" relates to "one or more embodiments of the present disclosure". Expressions such as "one or more" and "one or more" before a list of elements modify the entire list of elements and not the individual elements of the list.

[0041] Throughout the specification, when referring to "A and / or B", this means A, B, or A and B, unless otherwise stated to the contrary, and when referring to "C to D", this means greater than or equal to C and less than or equal to D, unless otherwise stated to the contrary.

[0042] When constructs such as "at least one of A, B, and C", "at least one of A, B, or C", "at least one selected from the group of A, B, and C", or "at least one selected from among A, B, and C" are used to specify a list of elements A, B, and C, the construct can refer to any and all suitable combinations.

[0043] The term "use" can be regarded as a synonym for the term "utilize". As used herein, terms such as "substantially", "approximately", and similar terms are used as terms of approximation rather than degree, and are for taking into account the inherent variations in measured or calculated values that would be recognized by a person of ordinary skill in the art.

[0044] As used herein, terms such as first, second, third, etc. may be used to describe various elements, components, regions, layers, and / or sections, but these elements, components, regions, layers, and / or sections should not be limited by these terms. These terms are used to distinguish one element, component, region, drawing layer, or cross-section from another. Thus, the first element, component, region, layer, or section discussed below is not outside the teachings of the exemplary embodiments and could be termed a second element, component, region, layer, or section.

[0045] As shown in the drawings, for ease of explanation, spatial relative terms such as "beneath", "below", "lower", "above", "upper", etc. may be used herein to describe the relationship of one element or feature to another (etc.). The spatially relative position is to be understood to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if the device in the figures is turned over, an element described as "beneath" or "below" another element would be understood as "above" or "upper" to the other element. Thus, the term "below" can encompass both upward and downward directions.

[0046] The terms used herein are for the purpose of describing embodiments of the present disclosure and are not intended to be limiting of the present disclosure.

[0047] Before describing an electrode plate according to an embodiment of the present invention with reference to the accompanying drawings, a secondary battery including the electrode plate will be described in detail below.

[0048] FIG. 1 is a perspective view showing an electrode plate according to an embodiment of the present invention and a secondary battery in which an electrode assembly including the same can be provided, and FIG. 2 is a cross-sectional view showing a state in which a plurality of electrode plates are coupled to each other.

[0049] Referring to FIGS. 1 and 2, the secondary battery 100 may include an electrode assembly 200 and a case 300.

[0050] The electrode assembly 200 includes a plurality of electrode plates 210, 220 and a separator 230. More specifically, the plurality of electrode plates 210, 220 may include a first electrode plate 210 and a second electrode plate 220.

[0051] Such an electrode assembly 200 may be in a form in which a laminate including the first electrode plate 210, the second electrode plate 220, and the separator 230 is repeatedly wound or laminated.

[0052] For example, the electrode assembly 200 may be of a laminated type in which the electrode plates 210, 220 are arranged to be laminated in a plurality of layers. Alternatively, the electrode assembly 200 may be of a jelly-roll type that is repeatedly wound. In the present invention, the case where the electrode assembly 200 is of a laminated type will be described as an example.

[0053] On the other hand, in the manufacturing process of the laminated type electrode assembly 200, it is common to perform a primary lamination process and a secondary process.

[0054] In the primary lamination process, a full cathode and a full anode can be laminated. Here, the full cathode may be, for example, the remaining ones among the plurality of first electrode plates 210 excluding the outermost first electrode plate 210A. And the full anode may be the second electrode plate 220.

[0055] In the secondary lamination process, a half cathode can be laminated on one or more sides of the outermost sides with respect to the lamination direction. Here, the half cathode may be the outermost first electrode plate 210A among the first electrode plates 210.

[0056] For the sake of cost, FIG. 2 illustrates the electrode assembly 200 with a half cathode laminated on the upper outermost periphery of the electrode assembly 200. However, it is also possible to laminate half cathodes on each of the upper outermost periphery and both side outermost peripheries of the electrode assembly 200.

[0057] Here, the double-sided cathode and the double-sided anode have active materials coated on both sides of the base material, and the half cathode has a current collector layer with a current collector layer located only on one side. Here, the current collector layer may be an active material layer. A detailed description of such a double-sided cathode, double-sided anode, and half cathode will be omitted.

[0058] The separator 230 may be interposed between the first electrode plate 210 and the second electrode plate 220. The separator 230 prevents short circuit between the first electrode plate 210 and the second electrode plate 220 and enables the movement of lithium ions. For this purpose, the separator 230 may be relatively larger in size than the first electrode plate 210 or the second electrode plate 220.

[0059] As an example, the material of the separator 230 may be made of polyethylene, polypropylene, or a composite film of polyethylene and polypropylene, but is not limited thereto.

[0060] Such a separator 230 may be cut into unit lengths and disposed between the first electrode plate 210 and the second electrode plate 220, or one separator 230 in the form of a ribbon may be disposed in a zigzag form between the first electrode plate 210 and the second electrode plate 220. Different from this, the separator 230 may also be provided to wind in one direction between the first electrode plate 210 and the second electrode plate 220. The arrangement form of the separator 230 is not limited to a specific form.

[0061] The case 300 can accommodate the electrode assembly 200. The aforementioned electrode assembly 200 is accommodated in the case 300 together with the electrolytic solution.

[0062] The case 300 as described above may be any one of a pouch type, a cylindrical type, and a rectangular type. The pouch type case 300 may be manufactured by bending plate-shaped exterior materials so as to face each other and then pressing or drawing one surface so as to include a recess on one surface.

[0063] The electrode assembly 200 is accommodated in a recess (not shown). A sealing portion 310 is provided at the outer peripheral edge of the recess, and the sealing portion 310 is sealed by a method such as heat fusion in a state where the electrode assembly 200 is accommodated in the recess.

[0064] On the other hand, among the plurality of electrode plates 210 and 220, the aforementioned first electrode plate 210 may be a negative electrode, the second electrode plate 220 may be a positive electrode, or vice versa. The first electrode plate 210 and the second electrode plate 220 can be electrically connected to the outside of the secondary battery 100 through the plate-shaped terminal 250. And the insulating tape 240 can be attached to the portion where the plate-shaped terminal 250 contacts the case 300. The insulating tape 240 can prevent the plate-shaped terminal 250 and the case 300 from being energized.

[0065] Hereinafter, with reference to the drawings, the electrode assembly 200 according to an embodiment of the present invention will be described in more detail.

[0066] FIG. 2 is a cross-sectional view showing a state where a plurality of electrode plates are coupled to each other, and FIG. 3 is a perspective view showing an extraction of the electrode plates from the secondary battery of FIG. 1.

[0067] Referring to FIGS. 2 and 3, the electrode assembly 200 according to an embodiment of the present invention includes a plurality of electrode plates 210 and 220 as described above, and each of the plurality of electrode plates 210 and 220 includes a current collector layer 201A and a plate layer 204 disposed on a part of the current collector layer 201A. Here, since the plate layer 204 may be an electrode active material layer used in a general secondary battery, a detailed description thereof will be omitted.

[0068] Based on the internal structure, the collector layer 201A includes a base layer E, and a first conductive layer F1 and a second conductive layer F2 located on the upper and lower surfaces of the base layer E, respectively.

[0069] The base layer E may include, for example, polyethylene terephthalate (PET).

[0070] Alternatively, the base layer E may include, for example, one or more of polyamide, polyimide, polybutylene terephthalate, polyethylene naphthalate, polycarbonate, polyethylene, polypropylene, polyethylene propylene, acrylonitrile-butadiene-styrene copolymer, polyvinyl alcohol, polystyrene, polyvinyl chloride, polyvinylidene fluoride, polytetrafluoroethylene, sodium polystyrene sulfonate, polyacetylene, silicone rubber, polyoxymethylene, polyphenylene ether, polyphenylene sulfide, polyethylene glycol, polysulfur nitride-based, polyphenylene, polypyrrole, polyaniline, polythiophene, polypyridine, cellulose, starch, protein, epoxy resin, phenolic resin, derivatives of the foregoing materials, cross-linked products of the foregoing materials, and copolymers of the foregoing materials.

[0071] On the other hand, the base layer E may further include an additive. The additive may include one or more of a metal material and an inorganic non-metallic material.

[0072] For example, the metal material additive may be one or more of aluminum, aluminum alloy, copper, copper alloy, nickel, nickel alloy, titanium, titanium alloy, iron, iron alloy, silver, and silver alloy.

[0073] And the inorganic non-metallic material additive is, for example, one or more of a carbon-based material, aluminum oxide, silicon dioxide, silicon nitride, silicon carbide, boron nitride, silicate, and titanium oxide, and is, for example, one or more of a glass material, a ceramic material, and a ceramic composite material. The carbon-based material additive may be, for example, one or more of graphite, superconducting carbon, acetylene black, carbon black, ketjen black, carbon dots, carbon nanotubes, graphene, and carbon nanofibers.

[0074] On the other hand, the additive may further include a carbon-based material coated with a metal material. For example, it may be one or more of graphite powder coated with nickel and carbon fiber coated with nickel.

[0075] On the other hand, the first conductive layer F1 and the second conductive layer F2 may contain aluminum. More specifically, the first conductive layer F1 and the second conductive layer F2 may contain one or more of a metal material, a carbon-based conductive material, and a conductive polymer material.

[0076] On the other hand, the current collector layer 201A described above may include a current collecting portion 202 and a plain portion 203 based on the external shape.

[0077] The current collecting portion 202 has the electrode plate layer 204 located on at least one surface. The current collecting portion 202 may be, for example, in the shape of a square plate. As shown in FIG. 3, the electrode plate layer 204 may be located in the remaining portion excluding the peripheral region of the current collecting portion 202. Different from this, although not shown, the electrode plate layer 204 may also be located on the entire current collecting portion 202.

[0078] The plain portion 203 extends outward from the current collecting portion 202. The plain portion 203 may be a portion where the electrode plate layer 204 is not located. The plain portion 203 may be, for example, in the shape of a ribbon.

[0079] On the one hand, as described above, the plurality of electrode plates 210 and 220 include a first electrode plate 210 and a second electrode plate 220. A part of the first conductive layer F1 and a part of the second conductive layer F2 are extended and joined at the current collecting layers 201A of the first electrode plate 210 and the second electrode plate 220, respectively, from the base layer E. That is, as shown in FIG. 2, a part of the first conductive layer F1 and a part of the second conductive layer F2 extend further from the plain portion 203 and the ends thereof are joined to each other.

[0080] Thereby, when the current collecting layers 201A of the plurality of first electrode plates 210 are joined to each other, the plurality of first electrode plates 210 can be electrically connected. Further, when the current collecting layers 201A of the plurality of second electrode plates 220 are joined to each other, the plurality of second electrode plates 220 can also be electrically connected.

[0081] FIG. 4 is a cross-sectional view showing a process of manufacturing the current collecting layer of the electrode plate in FIG. 3. Referring to FIG. 4, the base layer E included in the current collecting layer 201A may include a body portion E1 and an inclined portion E2.

[0082] Unlike the inclined portion E2 described later, the body portion E1 has a uniform thickness. The body portion E1 may be such that the entire current collecting portion 202 is located in a part of the body portion E1. Alternatively, although not shown, the body portion E1 may be located only in the current collecting portion 202.

[0083] The inclined portion E2 is integral with the body portion E1 and the thickness thereof gradually decreases toward the end. The shape of the vertical cross-section of the inclined portion E2 may be, for example, triangular. The inclined portion E2 may be located up to a portion adjacent to the end of the plain portion 203 in the current collecting layer 201A. Alternatively, the end of the inclined portion E2 may be located in the middle portion of the plain portion 203, and the remaining portion of the plain portion 203 may be such that the first conductive layer F1 and the second conductive layer F2 are joined.

[0084] As described above, in the current collecting layer 201A, the regions where the body portion E1 and the inclined portion E2 are located can be varied according to the design of the electrode assembly 200, and thus are not limited to specific positions. However, it may be advantageous for the body portion E1 to be located in many parts of the current collecting layer 201A in order to increase the rigidity of the current collecting layer 201A.

[0085] On the other hand, the aforementioned first conductive layer F1 and second conductive layer F2 are located on both surfaces of the body portion E1 and the inclined portion E2 respectively, and a part of the ends are coupled to each other, whereby the first conductive layer F1 and the second conductive layer F2 are electrically connected.

[0086] FIG. 5 is a cross-sectional view showing a current collecting layer according to a modified example.

[0087] Referring to FIG. 5, the current collecting layer 201B according to the modified example may include only the body portion E1 without the inclined portion E2 (see FIG. 4), unlike the aforementioned current collecting layer 201A (see FIG. 4). The current collecting layer 201B according to such a modified example can simplify the manufacturing process as compared with the aforementioned current collecting layer 201A.

[0088] Returning to FIG. 2, the plurality of electrode plates 210 and 220 may be joined to each other in the vertical direction at the plain portions 203 adjacent to each other.

[0089] More specifically, when the electrode assembly 200 is of a laminated type, the first electrode plate 210 and the second electrode plate 220 may be alternately laminated with each other with the separation film 230 interposed therebetween. There may be a plurality of the first electrode plates 210 and the second electrode plates 220. In FIG. 2, three of the first electrode plates 210 and the second electrode plates 220 are shown respectively, but the present invention is not limited thereto, and the number of the first electrode plates 210 and the second electrode plates 220 may be varied according to the design of the secondary battery 100.

[0090] In the electrode assembly 200 according to an embodiment of the present invention, the plain portions 203 of the first electrode plate 210 are arranged side by side in the vertical direction, and the plain portions 203 of the second electrode plate 220 are arranged side by side in the vertical direction. Although not shown, the plain portion 203 of the first electrode plate 210 may be separated from the plain portion 203 of the second electrode plate 220 in the left - right direction.

[0091] On the other hand, such plain portions 203 may be joined by a welding method. For example, a plurality of plain portions 203 may be grouped together and joined by a welding method such as laser, resistance welding, and ultrasonic welding.

[0092] On the other hand, the length of the plain portion 203 is not limited to a specific numerical value, and it is sufficient if the plain portions 203 can be joined to each other. Since the length of the plain portion 203 can be varied according to the design of the electrode assembly 200, it is not limited to a specific length.

[0093] Since the electrode plates included in the aforementioned electrode assembly 200 include a current - collecting layer 201A in which a part of the first conductive layer F1 and the second conductive layer F2 are joined to each other, it is possible to energize a plurality of electrode plates 210 and 220 only by welding the plain portions 203 to each other.

[0094] The manufacturing process of the electrode assembly 200 according to an embodiment of the present invention as described above will be described with reference to the drawings.

[0095] FIGS. 6 and 7 are drawings showing the process of manufacturing the electrode assembly.

[0096] FIG. 6 is a cross - sectional view showing a state in which the electrode plates are arranged side by side in the vertical direction.

[0097] Referring to FIG. 6, the first electrode plate 210 and the second electrode plate 220 are laminated. The first electrode plate 210 and the second electrode plate 220 may be sequentially laminated with the separation film 230 interposed therebetween.

[0098] FIG. 7 is a cross - sectional view showing the process in which the plain portions of the plurality of current - collecting layers are welded by ultrasonic welding.

[0099] Referring to FIG. 7, the plurality of second electrode plates 220 may be welded to each other at the non-coated portions 203 by a welding horn T used for ultrasonic welding. At this time, since the first conductive layer F1 and the second conductive layer F2 of the current collector layer 201A of the plurality of second electrode plates 220 are electrically connected to each other, all of the second electrode plates 220 can be electrically connected. And although not shown, the plurality of first electrode plates 210 can also be electrically connected to each other.

[0100] In a conventional secondary battery including a resin-metal composite substrate, there is a problem that when welding the non-coated portions of the electrodes, it contacts only one surface in the metal film. In order to solve this, it is necessary to go through a current-carrying process for passing an electric current through the metal film, so the manufacturing process may increase.

[0101] However, as described above, the electrode assembly 200 according to an embodiment of the present invention can electrically connect the first electrode plates 210 to each other and electrically connect the second electrode plates 220 to each other using only a general ultrasonic welding method without performing a separate current-carrying process.

[0102] As described above, the electrode assembly 200 according to an embodiment of the present invention does not need to perform a current-carrying process in which a foil is additionally folded and inserted one by one between the electrode plates as in the conventional case. Therefore, not only can the manufacturing time be shortened, but also the manufacturing cost can be reduced.

[0103] Although various embodiments of the present invention have been described above, the drawings and the detailed description of the invention referred to so far are merely exemplary of the present invention, which has been used only for the purpose of explaining the present invention and not for the purpose of limiting the meaning or the scope of the present invention described in the claims. Therefore, those having ordinary knowledge in the technical field should be able to understand that various modifications and equivalent other embodiments are possible hereafter. Therefore, the true technical protection scope of the present invention should be determined by the technical idea of the appended claims.

Explanation of Reference Numerals

[0104] 100: Secondary battery 200: Electrode assembly 201A, 201B: Current collector layer 202: Current collector part 203: Plain part 204: Electrode plate layer 210: First electrode plate 220: Second electrode plate 230: Separator 300: Case E: Base layer E1: Body part E2: Inclined part F1: First conductive layer F2: Second conductive layer

Claims

1. An electrode plate comprising a base layer, a current collecting layer including a first conductive layer and a second conductive layer located on the upper and lower surfaces of the base layer respectively, and a plate layer located on at least one surface of the current collecting layer, wherein a part of the first conductive layer and a part of the second conductive layer are extended and joined from the base layer, the electrode plate.

2. The base layer is a body part, integrated with the body part and including an inclined part whose thickness gradually decreases toward the end, the electrode plate according to claim 1.

3. The current collecting layer is a current collecting part with the plate layer located on at least one surface, a plain part extending from the current collecting part to the outside, and includes a part of the first conductive layer and a part of the second conductive layer extend further from the plain part and the ends are joined to each other, the electrode plate according to claim 1.

4. The base layer is one or more of polyethylene terephthalate, polyamide, polyimide, polybutylene terephthalate, polyethylene naphthalate, polycarbonate, polyethylene, polypropylene, polyethylene propylene, acrylonitrile - butadiene - styrene copolymer, polyvinyl alcohol, polystyrene, polyvinyl chloride, polyvinylidene fluoride, polytetrafluoroethylene, sodium polystyrene sulfonate, polyacetylene, silicone rubber, polyoxymethylene, polyphenylene ether, polyphenylene sulfide, polyethylene glycol, polysulfur nitride, polyphenylene, polypyrrole, polyaniline, polythiophene, polypyridine, cellulose, starch, protein, epoxy resin, phenolic resin, derivatives of the foregoing materials, cross-linked bodies of the foregoing materials, and copolymers of the foregoing materials, the electrode plate according to claim 1.

5. The base layer further includes an additive, and the additive includes one or more of a metal material and an inorganic non-metal material, the electrode plate according to claim 1.

6. The first conductive layer and the second conductive layer include aluminum, the electrode plate according to claim 1.

7. The first conductive layer and the second conductive layer include any one or more of nickel, copper, iron, and alloys containing these, the electrode plate according to claim 1.

8. The first conductive layer and the second conductive layer include one or more of a metal material, a carbon-based conductive material, and a conductive polymer material, the electrode plate according to claim 1.

9. An electrode assembly including a plurality of electrode plates and a separator membrane, with the plurality of electrode plates laminated with the separator membrane interposed therebetween, each of the plurality of electrode plates, a base layer, and a current collecting layer including a first conductive layer and a second conductive layer that are located on the upper and lower surfaces of the base layer respectively, are relatively longer than the base layer, and a part of which is coupled to each other, an electrode plate layer disposed on a part of the current collecting layer, and includes an electrode assembly.

10. The electrode assembly according to claim 9, wherein the base layer has a thickness that sequentially decreases at one end.

11. The base layer, a body portion, The electrode assembly according to claim 9, including an inclined portion that is integral with the body portion and has a thickness that sequentially decreases toward the end.

12. The electrode assembly according to claim 9, wherein the current collecting layers included in each of the plurality of electrode plates are coupled to each other.

13. The current collecting layer, a current collecting portion where the electrode plate layer is located on at least one surface, a plain portion extending from the current collecting portion to the outside, and includes an electrode assembly according to claim 9.

14. The plurality of electrode plates, The electrode assembly according to claim 9, including a first electrode plate and a second electrode plate.

15. The base layer, The electrode assembly according to claim 9, including one or more of polyethylene terephthalate, polyamide, polyimide, polybutylene terephthalate, polyethylene naphthalate, polycarbonate, polyethylene, polypropylene, polyethylene propylene, acrylonitrile-butadiene-styrene copolymer, polyvinyl alcohol, polystyrene, polyvinyl chloride, polyvinylidene fluoride, polytetrafluoroethylene, sodium polystyrene sulfonate, polyacetylene, silicone rubber, polyoxymethylene, polyphenylene ether, polyphenylene sulfide, polyethylene glycol, polysulfur nitride, polyphenylene, polypyrrole, polyaniline, polythiophene, polypyridine, cellulose, starch, protein, epoxy resin, phenolic resin, derivatives of the foregoing materials, cross-linked bodies of the foregoing materials, and copolymers of the foregoing materials.

16. The electrode assembly according to claim 9, wherein the base layer further includes an additive, and the additive includes one or more of a metal material and an inorganic non-metal material.

17. The electrode assembly according to claim 9, wherein the first conductive layer and the second conductive layer include aluminum.

18. The electrode assembly according to claim 9, wherein the first conductive layer and the second conductive layer contain any one or more of nickel, copper, iron, and alloys containing these.

19. The electrode assembly according to claim 9, wherein the first conductive layer and the second conductive layer contain one or more of a metal material, a carbon-based conductive material, and a conductive polymer material.

20. An electrode assembly, a case for housing the electrode assembly, and the electrode assembly is the electrode assembly according to any one of claims 9 to 19, a secondary battery.

Images