Electrode for rechargeable battery, electrode assembly including the same, and rechargeable battery

Abstract

Provided are an electrode, and an electrode assembly and a rechargeable battery including the same, the electrode including: a substrate including an electrode uncoated portion and an electrode active portion; a functional layer on the substrate; and an active material layer on the functional layer. The functional layer includes a first portion overlapping the electrode active portion and a second portion extending from the first portion to the electrode uncoated portion. The electrode is used for a rechargeable battery.

Description

Technical Field

[0001] Embodiments of the present disclosure relate to an electrode (eg, an electrode for a rechargeable battery), and an electrode assembly and a rechargeable battery (eg, a lithium rechargeable battery) including the electrode. Background Art

[0002] Rechargeable batteries, which have relatively high energy density and are (easily) portable, are used as driving power sources for mobile information terminals such as portable phones, notebooks (or laptop computers), and / or smart phones, etc.

[0003] The rechargeable battery may include an electrode assembly in which a negative electrode, a separator, and a positive electrode are sequentially stacked, and the positive electrode and the negative electrode may be formed in different areas or have different areas.

[0004] If the areas of the two different electrodes are different, the sizes of the active material layers of different polarities will be different. Therefore, the exposed substrate (e.g., current collector) and the active material layers of different polarities may contact each other, resulting in a short circuit. If a short circuit occurs, a large current may flow into / out of any one electrode in a short time, causing the rechargeable battery to catch fire or explode.

[0005] To solve this problem, one or more suitable insulating layers may be formed, and a material having relatively low thermal conductivity may be used as the insulating layer.

[0006] If a material with relatively low thermal conductivity is used as an insulating layer and the rechargeable battery is quickly charged or the output of the rechargeable battery is increased, a portion where current is concentrated may occur. In this case, the temperature of the rechargeable battery may rise, thereby increasing the possibility of an unexpected fire. Summary of the invention

[0007] Aspects of one or more embodiments of the present disclosure relate to an electrode that can prevent or reduce the risk of short circuit and prevent or reduce sudden heat increase at a portion where current is concentrated (e.g., protect against sudden heat increase at a portion where current is concentrated), as well as an electrode assembly and a rechargeable battery (e.g., a lithium rechargeable battery) including the electrode.

[0008] Additional aspects will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the disclosed presented embodiments.

[0009] An electrode for a rechargeable battery according to one or more embodiments of the present disclosure includes: a substrate including an electrode uncoated portion and an electrode active portion; a functional layer on the substrate; and an active material layer on the functional layer. The functional layer includes a first portion overlapping the electrode active portion and a second portion extending from the first portion to the electrode uncoated portion.

[0010] In one or more embodiments, the resistance (e.g., resistance value) of the functional layer may be greater than the resistance (e.g., resistance value) of the substrate, and may be less than the resistance (e.g., resistance value) of the active material layer. The resistance (e.g., resistance value) of the functional layer may be 5 to 25 times greater than the resistance (e.g., resistance value) of the substrate.

[0011] In one or more embodiments, the area of ​​the second portion may be 60% or less of the area of ​​the electrode uncoated portion. The length of the second portion may be greater than 0 mm and 5 mm or less. The length of the electrode uncoated portion may be 2 mm or more and 10 mm or less.

[0012] In one or more embodiments, the boundary line of the functional layer may be within the boundary line of the substrate.

[0013] In one or more embodiments, the electrode uncoated portion may protrude from one side of the electrode active portion.

[0014] In one or more embodiments, the active material layer may include a positive electrode active material (eg, a positive electrode active material for a rechargeable battery).

[0015] In one or more embodiments, the active material layer may include an active material represented by Chemical Formula A1.

[0016] Chemical formula A1

[0017] Li a11 Ni x11 M 11 y11 M 12 1-x11-y11 O2

[0018] In the chemical formula A1, 0.9≤a11≤1.8, 0.3≤x11≤1, and 0≤y11≤0.7, and M 11 and M 12 Each can independently be (e.g., selected from the following): Al, B, Ce, Co, Cr, F, Mg, Mn, Mo, Nb, P, S, Si, Sr, Ti, V, W, Zr and / or (e.g., any suitable) combination thereof.

[0019] In one or more embodiments, the functional layer may include the compound represented by Chemical Formula 1, the compound represented by Chemical Formula 2, and / or (eg, any suitable) combination thereof.

[0020] Chemical formula 1

[0021] Li a1 M 1 x1 Fe (1-x1) PO4

[0022] In Chemical Formula 1, 0.90≤a1≤1.5 and 0≤x1≤0.4, and M 1 It may be Mg, Co, Ni and / or (eg, any suitable) combinations thereof.

[0023] Chemical formula 2

[0024] Li a2 Mn x2 Fe (1-x2) PO4

[0025] In Chemical Formula 2, 0.90≤a2≤1.5 and 0.1≤x2≤1.

[0026] An electrode assembly according to one or more embodiments of the present disclosure includes: a first electrode including the above-mentioned electrode; a second electrode having a polarity opposite to that of the first electrode; and a separator between the first electrode and the second electrode.

[0027] In one or more embodiments, a distance between a boundary line of the first electrode and a boundary line of the second electrode may be greater than 0 mm and 5 mm or less.

[0028] In one or more embodiments, the first electrode, the separator, and the second electrode may have a sheet shape, and may be alternately and repeatedly stacked.

[0029] A rechargeable battery according to one or more embodiments of the present disclosure includes the electrode assembly and an electrolyte.

[0030] If an electrode according to one or more embodiments of the present disclosure is used, it is possible to provide a safe electrode that does not cause the risk of short circuit and sudden heat increase at a portion where current is concentrated (e.g., a terminal), or reduces the risk of short circuit and sudden heat increase, as well as an electrode assembly and a rechargeable battery including the safe electrode. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 is a schematic plan view of an electrode according to one or more embodiments of the present disclosure.

[0032] Figure 2According to one or more embodiments of the present disclosure, Figure 1 A schematic cross-sectional view taken along line II-II'.

[0033] Figure 3 is a schematic exploded view of a stacked electrode assembly according to one or more embodiments of the present disclosure. DETAILED DESCRIPTION

[0034] The present disclosure can be modified in many alternative forms, and therefore specific embodiments will be shown in the drawings and described in more detail. However, it should be understood that this is not intended to limit the present disclosure to the particular form disclosed, but on the contrary, it is intended to cover all modifications, equivalents and substitutes falling within the spirit and scope of the present disclosure.

[0035] Hereinafter, example embodiments will be described in more detail with reference to the accompanying drawings. However, the present disclosure may be implemented in a variety of different forms and should not be construed as being limited to the embodiments shown herein. Instead, these embodiments are provided as examples so that the present disclosure will be thorough and complete and will fully convey the aspects and features of the present disclosure to those skilled in the art. Therefore, processes, elements, and techniques that are not necessary for a person of ordinary skill in the art to fully understand the aspects and features of the present disclosure may not be described.

[0036] For better understanding and ease of description, the size and thickness of the components shown in the drawings may be exaggerated or reduced, and the present disclosure is not limited to the size and thickness shown. In the drawings, the thickness of layers, films, panels and / or regions, etc. may be exaggerated for clarity. In the drawings, the thickness of some layers and regions may be exaggerated for better understanding and ease of description.

[0037] Unless otherwise noted, like reference numerals denote like elements throughout the accompanying drawings and written description, and thus, a repeated description thereof may not be provided.

[0038] It will be understood that, although the terms "first", "second", "third", etc. may be used herein to describe various elements, components, regions, layers and / or parts, these elements, components, regions, layers and / or parts should not be limited by these terms. These terms are used to distinguish one element, component, region, layer or part from another element, component, region, layer or part. Therefore, without departing from the spirit and scope of the present disclosure, the first element, first component, first region, first layer or first part described below may be referred to as the second element, second component, second region, second layer or second part.

[0039] It will be understood that when an element such as a layer, film, region, or substrate is referred to as being "on" another element, it can be directly on the other element or one or more intervening elements may be present. Additionally, it will be understood that when an element is referred to as being "between" two elements, it can be the only element between the two elements or one or more intervening elements may also be present.

[0040] As used herein, the singular forms "one", "an" and "the (the)" are also intended to include plural forms, unless the context clearly states otherwise. It will be further understood that when the terms "include", "comprise", "have" and variations thereof are used in this specification, the features, integral bodies, steps, operations, elements and / or components stated are indicated, but one or more other features, integral bodies, steps, operations, elements, components and / or their groups are not excluded from existence or addition. As used herein, the term "and / or" includes any combination and all combinations of one or more of the related listed items. Unless otherwise clear by the disclosure, the expressions such as "at least one (kind / person) in ...", "multiple", "one (kind / person) in ..." and other postposition / preposition phrases when after / before a column of elements should be understood to include disjunctions if written as conjunction lists, and vice versa. For example, the expressions "at least one of a, b or c", "at least one of a, b and / or c", "one selected from the group consisting of a, b and c", "at least one selected from a, b and c", "at least one from a, b and c", "one from a, b and c", "at least one from a to c" mean only a, only b, only c, both a and b, both a and c, both b and c, all of a, b and c or variations thereof.

[0041] Figure 1 is a schematic plan view of an electrode according to one or more embodiments of the present disclosure, Figure 2 According to one or more embodiments of the present disclosure, Figure 1 A schematic cross-sectional view taken along line II-II'.

[0042] like Figure 1 and Figure 2 As shown in FIG. 1 , an electrode according to one or more embodiments of the present disclosure may include a substrate 70, a functional layer 71 formed on the substrate 70, and an active material layer 72 formed on the functional layer 71. If the electrode is a positive electrode, the substrate 70 may be aluminum (Al).

[0043] The functional layer 71 may include a material including a compound represented by Chemical Formula 1, a compound represented by Chemical Formula 2, and / or (eg, any suitable) combination thereof:

[0044] Chemical formula 1

[0045] Li a1 M 1 x1 Fe (1-x1) PO4

[0046] In Chemical Formula 1, for example, 0.90≤a1≤1.5, 0≤x1≤0.4, M 1 It may be Mg, Co, Ni and / or (eg, any suitable) combinations thereof.

[0047] Chemical formula 2

[0048] Li a2 Mn x2 Fe (1-x2) PO4

[0049] In Chemical Formula 2, for example, 0.90≤a2≤1.5 and 0.1≤x2≤1.

[0050] The compound represented by Chemical Formula 1 may be a lithium iron phosphate compound. In Chemical Formula 1, the molar fraction of lithium may be suitably or appropriately adjusted between approximately (about) 0.9 and (about) 1.5, for example, 0.90≤a1≤1.2, or 0.95≤a1≤1.1. In Chemical Formula 1, Mn may be present instead of Fe, and the molar fraction may be 0≤x1≤0.7, 0≤x1≤0.5, 0≤x1≤0.3, 0≤x1≤0.1, or 0≤x1≤0.05.

[0051] The compound represented by Chemical Formula 2 may be a lithium iron manganese phosphate compound (lithium iron manganese phosphate). In Chemical Formula 2, similar to Chemical Formula 1, the molar fraction of lithium may be 0.90≤a2≤1.2 or 0.95≤a2≤1.1. In Chemical Formula 2, the molar fraction of manganese may be 0.2≤x2≤0.9, 0.3≤x2≤0.9, or 0.4≤x2≤0.8, and in particular, if 0.5≤x2≤0.9, the lithium ion conduction capacity is relatively high.

[0052] For example, the functional layer 71 may be a lithium transition metal phosphate and may include LiFePO4, LiMn 0.5 Fe 0.5 PO4 and / or LiMnPO4, etc.

[0053] The functional layer 71 may include the above materials, and may further include an adhesive and / or a conductive material. Here, the content (e.g., amount) of the material may be 80wt% to 95wt% relative to the total weight of the functional layer 71. The content (e.g., amount) of the adhesive may be 1wt% to 10wt% relative to the total weight of the functional layer 71, and the conductive material may be 0.1wt% to 10wt% relative to the total weight of the functional layer 71.

[0054] The binder may attach material particles within the functional layer 71 to each other, and may also attach material particles to the substrate 70. The binder may include a non-water-soluble binder, a water-soluble binder, and / or (eg, any suitable) combination thereof.

[0055] The non-water-soluble binder may include polyvinyl chloride, carboxylated polyvinyl chloride, polyvinyl fluoride, polymers including ethylene oxide, polyethylene propylene copolymers, polystyrene, polyvinyl pyrrolidone, polyurethane, polytetrafluoroethylene, polyvinylidene fluoride, polyethylene, polypropylene, polyamideimide, polyimide and / or (e.g., any suitable) combinations thereof.

[0056] Water-soluble adhesive can include rubber-like adhesive or polymer resin adhesive.Rubber-like adhesive can be (for example, can be selected from the following): styrene-butadiene rubber (SBR), acrylated styrene-butadiene rubber, acrylonitrile-butadiene rubber (ABR), acrylic rubber, butyl rubber, fluororubber and / or their (for example, any suitable) combination.Polymer resin adhesive can be (for example, can be selected from the following): polyethylene oxide, polyvinyl pyrrolidone, polyepichlorohydrin, polyphosphazene, polyacrylonitrile, ethylene-propylene-diene copolymer, polyvinyl pyridine, chlorosulfonated polyethylene, latex, polyester resin, acrylic resin, phenolic resin, epoxy resin, polyvinyl alcohol and / or their (for example, any suitable) combination.

[0057] If a water-soluble binder is used as the binder, it may further include a cellulose compound capable of imparting viscosity. The cellulose compound may be used by mixing one or more types (species) of carboxymethyl cellulose, hydroxypropyl methyl cellulose and / or methyl cellulose, etc. with an alkali metal salt. Na, K or Li may be used as the alkali metal.

[0058] Conductive materials (eg, conductors or electronic conductors) may be used to provide conductivity to the electrodes, and may include carbon-based materials, metal-based materials, conductive polymers, and / or (eg, any suitable) mixtures thereof.

[0059] A (for example, any suitable) conductive material may be included / used in the functional layer 71 as long as it does not cause chemical changes and is an electronic conductive material. For example, the conductive material may be a conductive material including: a carbon-based material such as natural graphite, artificial graphite, carbon black, acetylene black, Ketjen black and / or carbon fiber, etc.; a metal-based material such as metal powder or metal fiber containing copper, nickel, aluminum and / or silver, etc.; a conductive polymer such as a polyphenylene derivative, etc.; and / or a (for example, any suitable) mixture thereof.

[0060] The active material layer 72 may include a positive electrode active material, which may be a compound capable of reversibly intercalating and deintercalating lithium (lithium intercalation compound).

[0061] Examples of the positive electrode active material may be compounds represented by any one or more of the following molecular formulae (eg, any one or more selected from the following molecular formulae): Li a A 1-b X b D2(0.90≤a≤1.8, 0≤b≤0.5); Li a A 1-b X b O 2-c D c (0.90≤a≤1.8, 0≤b≤0.5, 0≤c≤0.05); Li a E 1-b X b O 2-c D c (0.90≤a≤1.8, 0≤b≤0.5, 0≤c≤0.05); Li a E 2-b X b O 4-c D c (0.90≤a≤1.8, 0≤b≤0.5, 0≤c≤0.05); Li a Ni 1-b-c Co b X c D α (0.90≤a≤1.8, 0≤b≤0.5, 0≤c≤0.5, 0<α≤2); Li a Ni 1-b-c Co b X c O 2-α T α (0.90≤a≤1.8, 0≤b≤0.5, 0≤c≤0.05, 0<α<2); Li a Ni 1-b-c Co b X c O2-α T2(0.90≤a≤1.8,0≤b≤0.5,0≤c≤0.05,0<α<2);Li a Nor 1-b-c Mn b X c D α (0.90≤a≤1.8,0≤b≤0.5,0≤c≤0.05\0<α≤2);Li a Nor 1-b-c Mn b X c O 2-α T α (0.90≤a≤1.8,0≤b≤0.5,0≤c≤0.05\0<α<2);Li a Nor 1-b- c Mn b X c O 2-α T2(0.90≤a≤1.8,0≤b≤0.5,0≤c≤0.05,0<α<2);Li a Nor b E c G d O2(0.90≤a≤1.8,0≤b≤0.9,0≤c≤0.5,0.001≤d≤0.1);Li a Nor b Co c Mn d G e O2(0.90≤a≤1.8,0≤b≤0.9,0≤c≤0.5,0≤d≤0.5,0.001≤e≤0.1);Li a NiG b O2(0.90≤a≤1.8,0.001≤b≤0.1);Li a CoG b O2(0.90≤a≤1.8,0.001≤b≤0.1);Li a Mn 1-b G b O2(0.90≤a≤1.8,0.001≤b≤0.1);Li a Mn2G b O4(0.90≤a≤1.8,0.001≤b≤0.1);Li a Mn 1-g G g PO4(0.90≤a≤1.8,0≤g≤0.5);QO2;QS2;LiQS2;V2O5;LiV2O5;LiZO2;LiVO4;Li (3-f)J2(PO4)3(0≤f≤2);Li (3-f) Fe2(PO4)3(0≤f≤2); and / or Li a FePO4(0.90≤a≤1.8).

[0062] In the above molecular formula, A may be a group including Ni, Co, Mn and / or (e.g., any suitable) combination thereof (e.g., consisting of Ni, Co, Mn and / or (e.g., any suitable) combination thereof), for example, may be selected from a group including Ni, Co, Mn and / or (e.g., any suitable) combination thereof (e.g., consisting of Ni, Co, Mn and / or (e.g., any suitable) combination thereof); X may be an element including Al, Ni, Co, Mn, Cr, Fe, Mg, Sr, V, a rare earth element and / or (e.g., any suitable) combination thereof (e.g., consisting of Al, Ni, Co, Mn, Cr, Fe, Mg, Sr, V, a rare earth element and / or (e.g., any suitable) combination thereof , any suitable) combination thereof), for example, can be selected from the group including Al, Ni, Co, Mn, Cr, Fe, Mg, Sr, V, rare earth elements and / or their (e.g., any suitable) combination thereof (e.g., consisting of Al, Ni, Co, Mn, Cr, Fe, Mg, Sr, V, rare earth elements and / or their (e.g., any suitable) combination thereof); D can be the group including O, F, S, P and / or their (e.g., any suitable) combination thereof (e.g., consisting of O, F, S, P and / or their (e.g., any suitable) combination thereof), for example, can be selected from the group including O, F, S, P and / or their (e.g., any suitable) combination thereof (e.g., consisting of O, F, S, P and / or its E may be a group including Co, Mn and / or their (e.g., any suitable) combination (e.g., consisting of Co, Mn and / or their (e.g., any suitable) combination), for example, it may be selected from a group including Co, Mn and / or their (e.g., any suitable) combination (e.g., consisting of Co, Mn and / or their (e.g., any suitable) combination); T may be a group including F, S, P and / or their (e.g., any suitable) combination (e.g., consisting of F, S, P and / or their (e.g., any suitable) combination), for example, it may be selected from a group including F, S, P and / or their (e.g., any suitable) combination. G may be a group including Al, Cr, Mn, Fe, Mg, La, Ce, Sr, V and / or (e.g., any suitable) combination thereof (e.g., consisting of Al, Cr, Mn, Fe, Mg, La, Ce, Sr, V and / or (e.g., any suitable) combination thereof), for example, may be selected from the group including Al, Cr, Mn, Fe, Mg, La, Ce, Sr, V and / or (e.g., any suitable) combination thereof (e.g., consisting of Al, Cr, Mn, Fe, Mg, La, Ce, Sr, V and / or (e.g., any suitable) combination thereof);Q may be a group including Ti, Mo, Mn and / or (e.g., any suitable) combination thereof (e.g., consisting of Ti, Mo, Mn and / or (e.g., any suitable) combination thereof), for example, may be selected from a group including Ti, Mo, Mn and / or (e.g., any suitable) combination thereof (e.g., consisting of Ti, Mo, Mn and / or (e.g., any suitable) combination thereof); Z may be a group including Cr, V, Fe, Sc, Y and / or (e.g., any suitable) combination thereof (e.g., consisting of Cr, V, Fe, Sc, Y and / or (e.g., any suitable) combination thereof), for example, may be selected from a group including Cr, V, Fe, Sc, Y and / or their (e.g., any suitable) combination (e.g., consisting of Cr, V, Fe, Sc, Y and / or their (e.g., any suitable) combination) is selected from the group; J can be a group including V, Cr, Mn, Co, Ni, Cu and / or their (e.g., any suitable) combination (e.g., consisting of V, Cr, Mn, Co, Ni, Cu and / or their (e.g., any suitable) combination), for example, can be selected from the group including V, Cr, Mn, Co, Ni, Cu and / or their (e.g., any suitable) combination (e.g., consisting of V, Cr, Mn, Co, Ni, Cu and / or their (e.g., any suitable) combination). ;

[0063] A compound of a positive electrode active material having a coating on the surface of the compound can be used, and / or a mixture of the compound and the compound having the coating (for example, any suitable) can be used. The coating can include a group comprising the following (for example, consisting of the following) (for example, selected from a group comprising the following (for example, consisting of the following)) at least one coating element compound: an oxide of a coating element, a hydroxide of a coating element, an oxyhydroxide of a coating element, an oxygen-containing carbonate of a coating element, and / or a hydroxycarbonate of a coating element. The compound constituting the coating can be amorphous or crystalline. The coating element included in the coating can include Mg, Al, Co, K, Na, Ca, Si, Ti, V, Sn, Ge, Ga, B, As, Zr and / or their (for example, any suitable) combination. The process for forming the coating can use a method (spraying and / or impregnation, etc.) that has no adverse effect on the active material properties of the active material layer.

[0064] Examples of the positive electrode active material may include a positive electrode active material represented by Chemical Formula A1.

[0065] Chemical formula A1

[0066] Li a11 Ni x11 M 11y11 M 12 1-x11-y11 O2

[0067] In chemical formula A1, for example, 0.9 ≤ a11 ≤ 1.8, 0.3 ≤ x11 ≤ 1 and 0 ≤ y11 ≤ 0.7, and M 11 and M 12 can each independently be (for example, selected from among the following): Al, B, Ce, Co, Cr, F, Mg, Mn, Mo, Nb, P, S, Si, Sr, Ti, V, W, Zr, and / or their (for example, any suitable) combination.

[0068] In chemical formula A1, for example, 0.4 ≤ x11 ≤ 1 and 0 ≤ y11 ≤ 0.6, 0.5 ≤ x11 ≤ 1 and 0 ≤ y11 ≤ 0.5, 0.6 ≤ x11 ≤ 1 and 0 ≤ y11 ≤ 0.4, 0.7 ≤ x11 ≤ 1 and 0 ≤ y11 ≤ 0.3, 0.8 ≤ x11 ≤ 1 and 0 ≤ y11 ≤ 0.2, or 0.9 ≤ x11 ≤ 1 and 0 ≤ y11 ≤ 0.1.

[0069] Specific examples of the positive electrode active material may include a lithium nickel cobalt composite oxide represented by chemical formula A2.

[0070] Chemical formula A2

[0071] Li a12 Ni x12 Co y12 M 13 1-x12-y12 O2

[0072] In chemical formula A2, for example, 0.9 ≤ a12 ≤ 1.8, 0.3 ≤ x12 < 1 and 0 < y12 ≤ 0.7, and M 13 can be (for example, selected from among the following): Al, B, Cr, F, Mg, Mn, Mo, Nb, P, S, Si, Sr, Ti, V, W, Zr, and / or their (for example, any suitable) combination.

[0073] In chemical formula A2, for example, 0.3 ≤ x12 ≤ 0.99 and 0.01 ≤ y12 ≤ 0.7, 0.4 ≤ x12 ≤ 0.99 and 0.01 ≤ y12 ≤ 0.6, 0.5 ≤ x12 ≤ 0.99 and 0.01 ≤ y12 ≤ 0.5, 0.6 ≤ x12 ≤ 0.99 and 0.01 ≤ y12 ≤ 0.4, 0.7 ≤ x12 ≤ 0.99 and 0.01 ≤ y12 ≤ 0.3, 0.8 ≤ x12 ≤ 0.99 and 0.01 ≤ y12 ≤ 0.2, or 0.9 ≤ x12 ≤ 0.99 and 0.01 ≤ y12 ≤ 0.1.

[0074] A specific example of the positive electrode active material may include a lithium nickel cobalt composite oxide represented by Chemical Formula A3.

[0075] Chemical formula A3

[0076] Li a13 Ni x13 Co y13 M 14 z13 M 15 1-x13-y13-z13 O2

[0077] In the chemical formula A3, for example, 0.9≤a13≤1.8, 0.3≤x13≤0.98, 0.01≤y13≤0.69 and 0.01≤z13≤0.69, M 14 can be (for example, can be selected from the following): Al, Mn and / or (for example, any suitable) combination thereof, M 15 It can be (for example, can be selected from the following): B, Ce, Cr, F, Mg, Mo, Nb, P, S, Si, Sr, Ti, V, W, Zr and / or their (for example, any suitable) combinations.

[0078] In the chemical formula A3, for example, 0.4≤x13≤0.98, 0.01≤y13≤0.59 and 0.01≤z13≤0.59; 0.5≤x13≤0.98, 0.01≤y13≤0.49 and 0.01≤z13≤0.49; 0.6≤x13≤0.98, 0.01≤y13≤0.39 and 0.01≤z13≤0 .39; 0.7≤x13≤0.98, 0.01≤y13≤0.29 and 0.01≤z13≤0.29; 0.8≤x13≤0.98, 0.01≤y13≤0.19 and 0.01≤z13≤0.19; or, 0.9≤x13≤0.98, 0.01≤y13≤0.09 and 0.01≤z13≤0.09.

[0079] If the negative electrode active material layer, which will be described in more detail later, includes silicon to achieve relatively high capacity, irreversible phenomena of silicon-based negative electrode active materials may occur. To solve or reduce the irreversible phenomena, the positive electrode active material may further include a sacrificial positive electrode material.

[0080] Lithium rechargeable batteries can be intended to improve life by compensating for the irreversibility of the negative electrode by including a sacrificial positive electrode material, but for example, the irreversibility of the positive electrode may also increase, causing the capacity of the positive electrode to decrease. However, for example, because the capacity of the positive electrode is relatively high compared to the capacity of the negative electrode, if the positive electrode includes a sacrificial positive electrode material (for example, when the positive electrode includes a sacrificial positive electrode material), the reduced capacity of the positive electrode may not reduce (for example, may not effectively or substantially reduce) the (for example, total) capacity of the lithium rechargeable battery. For example, silicon-based negative electrode active materials may cause volume expansion and contraction problems during the charge and discharge of the battery. If the cut-off voltage of the negative electrode is reduced during discharge, the contraction caused during discharge can be suppressed or reduced. As a result, the lithium rechargeable battery can improve the life characteristics by sacrificing some of the unused or unnecessary capacity of the positive electrode without (for example, effectively or substantially) reducing the capacity of the lithium rechargeable battery.

[0081] The lithium sacrificial positive electrode material can use a material having a large capacity and relatively high irreversibility (e.g., lithium nickel oxide and / or lithium molybdenum oxide, etc.). The sacrificial positive electrode material can be a material in which, if the lithium rechargeable battery is charged (e.g., when the lithium rechargeable battery is charged), Li ions are desorbed from the sacrificial positive electrode material at a voltage of about 2.75 to about 4.5 V. For example, the sacrificial positive electrode material can be (e.g., can be selected from the following): Li2NiO2, Li2MoO3 and / or (e.g., any suitable) combination thereof.

[0082] Based on the total 100wt% of the positive electrode active material, the content (e.g., amount) of the sacrificial positive electrode material may be greater than 0wt% to about 20wt% or less, for example, the content (e.g., amount) of the sacrificial positive electrode material may be about 5wt% to about 15wt% or about 5wt% to about 10wt%. The capacity and life characteristics of the lithium rechargeable battery may be improved simultaneously (e.g., synchronously) by using a sacrificial positive electrode material having the above content (e.g., amount).

[0083] For example, the positive electrode active material layer 72 may include the positive electrode active material, and may also include a binder and / or a conductive material. In one or more embodiments, based on the total weight of the positive electrode active material layer, the content (e.g., amount) of the positive electrode active material may be 90wt% to 98wt% or 90wt% to 95wt%. Based on the total weight of the positive electrode active material layer, the content (e.g., amount) of the binder and the conductive material may be 1wt% to 5wt%.

[0084] The binder can (effectively) allow the positive electrode active material particles to adhere to each other, can allow the positive electrode active material to adhere to the functional layer or the substrate, and can be the same as the binder included in the functional layer 71 .

[0085] The conductive material may be used to provide conductivity to the electrode, and may be the same as the conductive material included in the functional layer 71 .

[0086] For example, the substrate 70 according to one or more embodiments of the present disclosure may include an electrode active portion (or electrode active area) DA and an electrode uncoated portion (or electrode uncoated area) DB (see, e.g. Figure 1 ). The active material layer 72 may be formed at the electrode active portion DA and may not be formed on the electrode non-coating portion DB, and the substrate may be exposed on the electrode non-coating portion DB.

[0087] The electrode non-coating portion DB may be a portion in which the active material layer is not formed, and may be formed at an edge around the active material layer (e.g., surrounding the active material layer). However, the electrode non-coating portion DB according to one or more embodiments of the present disclosure may be a portion for leading current to the outside, and may protrude from the electrode active portion DA except for the base portion exposed at the edge around the active material layer (e.g., surrounding the active material layer).

[0088] The functional layer 71 may include a first portion 7 formed in the electrode active portion DA to overlap the active material layer 72 and a second portion 8 extending to the electrode non-coating portion DB.

[0089] The functional layer 71 may have a resistance (eg, a resistance value) greater than that of the substrate 70 and lower than that of the active material layer 72 to function as a resistance layer.

[0090] For example, the resistance of the functional layer 71 may be 5 to 25 times greater or 10 to 20 times greater than the resistance of the substrate 70 .

[0091] As described above, the resistance of the functional layer 71 can be greater than the resistance of the substrate 70, so that the contact resistance between the functional layer 71 and the negative electrode can be 5 to 25 times greater than the contact resistance if the substrate 70 and the negative electrode are in contact due to membrane shrinkage and / or membrane damage, etc. (for example, when the substrate 70 and the negative electrode are in contact due to membrane shrinkage and / or membrane damage, etc.). Therefore, for example, the short-circuit current can be relatively reduced, so that Joule heat is reduced. Therefore, the risk of fire caused by heat generation can be reduced.

[0092] The second portion 8 may be formed at a portion of the electrode non-coating portion DB so that current is drawn to the outside and the welding portion is exposed, and the area of ​​the second portion 8 may be formed to be 60% or less of the area of ​​the electrode non-coating portion DB.

[0093] For example, the length L2 of the electrode uncoated portion DB may be 2 mm or more and 10 mm or less, or 2 mm or more and 7 mm or less, and the length L1 of the second portion 8 may be greater than 0 and 5 mm or less, or 0.1 mm or more and 3 mm or less.

[0094] The functional layer 71 may be formed to have an area larger than that of the active material layer 72 and to protrude around the active material layer 72 , but may be (eg, may be formed to be) smaller than the substrate 70 so that the boundary line of the functional layer 71 is arranged within the boundary line of the substrate 70 .

[0095] The above electrodes can be used in a stacked electrode assembly. Figure 3 An electrode assembly according to one or more embodiments of the present disclosure is described.

[0096] Figure 3 is a schematic diagram of a stacked electrode assembly according to one or more embodiments of the present disclosure.

[0097] The electrode assembly 101 according to one or more embodiments of the present disclosure may be a stacked electrode assembly 101 in which the negative electrode 100 and the positive electrode 200 having a sheet shape are repeatedly stacked and the separator 300 having a sheet shape is interposed between the negative electrode 100 and the positive electrode 200 .

[0098] The separator 300 may be a polymer film that allows lithium ions to pass through (allows lithium ions to pass through). The separator may be made of a multi-film of polyethylene, polypropylene, polyvinylidene fluoride, or two or more thereof (for example, may include a multi-film of polyethylene, polypropylene, polyvinylidene fluoride, or two or more thereof), and may be made of a mixed multi-film such as a polyethylene / polypropylene double-layer separator, a polyethylene / polypropylene / polyethylene three-layer separator, and / or a polypropylene / polyethylene / polypropylene three-layer separator (for example, may include the aforementioned mixed multi-film).

[0099] The negative electrode 100 may include an electrode portion where an active material layer is formed at (on) a metal substrate (eg, a current collector) made of copper (Cu) and an uncoated portion where the metal substrate is exposed due to the active material not being coated.

[0100] The positive electrode 200 may include an electrode portion where an active material is applied to a metal substrate (eg, a current collector) made of aluminum (Al) and an uncoated portion where the metal substrate is exposed because the active material is not applied. Figure 1 and Figure 2 The electrodes shown in .

[0101] The negative electrode may be formed larger than the positive electrode, for example, the distance between the boundary line of the negative electrode and the boundary line of the positive electrode may be greater than 0 mm and 5 mm or less, or 0.5 mm or more and 3 mm or less.

[0102] If the negative electrode and the positive electrode are exposed to a relatively high temperature, the separator arranged between the negative electrode and the positive electrode will shrink, so that the active material layers of different polarities of the negative electrode and the positive electrode and the electrode uncoated portion are in contact with each other. As a result, a short circuit will occur. As the short-circuit current increases, Joule heat will increase. In one or more embodiments of the present disclosure, a functional layer having a resistance greater than the resistance of the substrate may be formed so that the negative electrode contacts the functional layer instead of directly contacting the substrate of the positive electrode. Therefore, for example, the short-circuit current can be relatively reduced, so that the Joule heat is reduced.

[0103] The plurality of electrode uncoated portions of the positive electrode 200 may be electrically connected to an external terminal, and the plurality of electrode uncoated portions of the negative electrode 100 may be electrically connected to an external terminal (e.g., uncoated portions of the same polarity may be electrically connected to the same external terminal). The electrode uncoated portion of each positive electrode 200 and the electrode uncoated portion of each negative electrode 100 may protrude substantially in the same direction, but the present disclosure is not limited thereto, and the electrode uncoated portion of the positive electrode 200 and the electrode uncoated portion of the negative electrode 100 may protrude in opposite directions and may be spaced and / or separated (e.g., spaced or separated) from each other.

[0104] The separator 300 may be formed larger than the negative electrode 100 and the positive electrode 200 to protrude outward from the negative electrode 100 and the positive electrode 200 .

[0105] The electrode assembly 101 may be housed in a pouch-shaped or can-shaped prismatic case together with an electrolyte to be used in a rechargeable battery.

[0106] The electrolyte may include a non-aqueous organic solvent and a lithium salt. The non-aqueous organic solvent may serve as a medium through which ions participating in the electrochemical reaction of the battery move.

[0107] The lithium salt may be a material dissolved in an organic solvent so that it is used as a supply source of lithium ions within the battery to achieve the basic operation of the lithium rechargeable battery, and it is used to promote the movement of lithium ions between the positive electrode and the negative electrode. Representative examples of lithium salts (e.g., used as supporting electrolyte salts) may include, for example, LiPF6, LiBF4, LiSbF6, LiAsF6, LiN(SO2C2F5)2, Li(CF3SO2)2N, LiN(SO3C2F5)2, LiC4F9SO3, LiClO4, LiAlO2, LiAlCl4, LiN(C x F 2x+1 SO2)C y F2y+1 One or more selected from the group consisting of SO2 (wherein x and y are natural numbers, such as integers from 1 to 20), LiCl, LiI, LiB(C2O4)2 (lithium bis(oxalato)borate (LiBOB)), and combinations thereof.

[0108] The concentration of the lithium salt may be used in the range of 0.1 M to 2.0 M. If the concentration of the lithium salt is included within the range, the electrolyte may have appropriate or suitable conductivity and viscosity so that the electrolyte exhibits excellent or suitable electrolyte performance and lithium ions move efficiently.

[0109] Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by those of ordinary skill in the art to which the present disclosure belongs. It will also be understood that terms (such as those defined in general dictionaries) should be interpreted as having a meaning consistent with their context in the relevant art and / or in this specification, and should not be interpreted in an idealized or overly formal sense, unless explicitly defined as such herein.

[0110] As used herein, the terms "substantially," "about," and similar terms are used as terms of approximation rather than terms of degree, and are intended to account for the inherent deviations in measured or calculated values ​​that one of ordinary skill in the art would recognize. As used herein, "about" includes the stated value and means within an acceptable range of deviations of the particular value as determined by one of ordinary skill in the art taking into account the measurement in question and the errors associated with the measurement of the particular quantity (i.e., the limitations of the measurement system). For example, "about" can mean within one or more standard deviations, or within ±30%, ±20%, ±10%, ±5% of the stated value.

[0111] In addition, any numerical range listed here is intended to include all sub-ranges of the same numerical precision contained in the listed range. For example, the range of "1.0 to 10.0" is intended to include all sub-ranges between the listed minimum value 1.0 and the listed maximum value 10.0 (and including the listed minimum value 1.0 and the listed maximum value 10.0), that is, having a minimum value equal to or greater than 1.0 and a maximum value equal to or less than 10.0, such as 2.4 to 7.6. Any maximum numerical limit listed here is intended to include all lower numerical limits contained therein, and any minimum numerical limit listed in this specification is intended to include all higher numerical limits contained therein. Therefore, the applicant reserves the right to modify this specification and the claims to explicitly list any sub-ranges within the range explicitly listed here.

[0112] Furthermore, the use of “may” when describing embodiments of the present disclosure refers to “one or more embodiments of the present disclosure.”

[0113] The portable device, vehicle and / or battery (e.g., battery controller) and / or any other related device or component according to the embodiments of the present disclosure described herein can be implemented using (e.g., any suitable) hardware, firmware (e.g., application specific integrated circuit), software, or a combination of software, firmware and hardware. For example, the various components of the device can be formed on an integrated circuit (IC) chip or on a separate IC chip. In addition, the various components of the device can be implemented on a flexible printed circuit film, a carrier package (TCP), a printed circuit board (PCB), or formed on a substrate. In addition, the various components of the device can be processes or threads running on one or more processors in one or more computing devices, and the one or more computing devices execute computer program instructions and interact with other system components to perform the various functions described herein. The computer program instructions are stored in a memory, which can be implemented in a computing device using a standard memory device such as a random access memory (RAM) as an example. The computer program instructions can also be stored in other non-temporary computer-readable media such as CD-ROMs, flash drives, etc. as examples. In addition, those skilled in the art should recognize that the functionality of various computing devices may be combined or integrated into a single computing device, or the functionality of a particular computing device may be distributed to one or more other computing devices without departing from the scope of the embodiments of the present disclosure.

[0114] Although the embodiments of the present disclosure have been described, it will be understood that the present disclosure should not be limited to these embodiments, but one or more suitable modifications and variations may be made by one of ordinary skill in the art within the spirit and scope of the present disclosure as defined by the appended claims and their equivalents.

Claims

1. An electrode, comprising: A substrate including an electrode uncoated portion and an electrode active portion; a functional layer on the substrate; as well as an active material layer on the first portion of the functional layer, wherein the functional layer comprises the first portion overlapping the electrode active portion and the second portion extending from the first portion to the electrode uncoated portion, and Wherein, the electrode is used in a rechargeable battery.

2. The electrode according to claim 1, wherein The resistance of the functional layer is greater than the resistance of the substrate and smaller than the resistance of the active material layer.

3. The electrode according to claim 2, wherein The electrical resistance of the functional layer is 5 to 25 times greater than the electrical resistance of the substrate.

4. The electrode according to claim 1, wherein The area of ​​the second portion is 60% or less of the area of ​​the electrode uncoated portion.

5. The electrode according to claim 4, wherein The length of the second portion is greater than 0 mm and is 5 mm or less.

6. The electrode according to claim 1, wherein The length of the electrode uncoated portion is 2 mm or more and 10 mm or less.

7. The electrode according to claim 1, wherein The boundary line of the functional layer is within the boundary line of the substrate.

8. The electrode according to claim 1, wherein The electrode uncoated portion protrudes from one side of the electrode active portion.

9. The electrode according to claim 1, wherein The active material layer includes a positive electrode active material.

10. The electrode according to claim 9, wherein The active material layer includes an active material represented by Chemical Formula A1: Chemical formula A1 Li a11 Ni x11 M 11 y11 M 12 1-x11-y11 O2 Wherein, in the chemical formula A1, 0.9≤a11≤1.8, 0.3≤x11≤1 and 0≤y11≤0.7, and M 11 and M 12 Each is independently selected from Al, B, Ce, Co, Cr, F, Mg, Mn, Mo, Nb, P, S, Si, Sr, Ti, V, W, Zr and their combinations.

11. The electrode according to claim 1, wherein The functional layer includes a compound represented by Chemical Formula 1, a compound represented by Chemical Formula 2, or a combination thereof: Chemical formula 1 Li a1 M 1 x1 Fe (1-x1) PO4 In Chemical Formula 1, 0.90≤a1≤1.5 and 0≤x1≤0.4, M 1 is Mg, Co, Ni or a combination thereof, Chemical formula 2 Li a2 Mn x2 Fe (1-x2) PO4 In Chemical Formula 2, 0.90≤a2≤1.5 and 0.1≤x2≤1.

12. An electrode assembly, comprising: A first electrode comprising the electrode according to claim 1; a second electrode having a polarity opposite to that of the first electrode; as well as A separator is between the first electrode and the second electrode.

13. The electrode assembly according to claim 12, wherein: A distance between a boundary line of the first electrode and a boundary line of the second electrode is greater than 0 mm and is 5 mm or less.

14. The electrode assembly according to claim 12, wherein: The first electrode, the separator, and the second electrode have a sheet shape and are alternately and repeatedly stacked. 15 . A rechargeable battery comprising the electrode assembly according to claim 12 and an electrolyte.

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