Composition, negative electrode, and battery

Abstract

To provide a composition that is adaptable to large current density while maintaining integrity of the entire structure, can avoid a problem such as a short cycle life and unfavorable safety of a battery due to breakage of the structure, and further achieves a purpose of having high energy density in a charge / discharge environment of large current density.SOLUTION: A composition comprises an active composition containing a niobium titanium oxide and a silicon active material. The niobium titanium oxide comprises a niobium element, a titanium element, and an oxygen element. Where Ptn is a weight ratio of the niobium titanium oxide to the active composition, and Ps is the weight ratio of the silicon active material to the active composition, a condition 0.12≤Ptn / Ps≤99.0 is satisfied. When specific conditions are satisfied, it helps to improve safety, cycle life, and energy density of the battery.SELECTED DRAWING: None

Description

Technical Field

[0001] The present invention relates to a composition, a negative electrode, and a battery, and particularly to a composition and a negative electrode capable of improving the safety, cycle life, and energy density of a battery.

Background Art

[0002] Current batteries aim at high energy density, high operating voltage, fast charging speed, and long cycle life in research and development, and carbon or graphite has been commonly used as a negative electrode material. However, the theoretical energy density of graphite is much lower than the needs for the kinetic energy of large power devices such as electric vehicles. In the cycle process of using a large current, carbon or graphite with a layered structure cannot withstand the rapid insertion and desorption of ions, and the structure is easily irreversibly collapsed, reducing the capacitance and storage life. Also, when the current density is too large, polarization is likely to occur, lithium ions are reduced to lithium metal on the surface of the electrode plate, and dendritic crystals of lithium are formed, often causing a short circuit inside the battery and posing safety concerns.

Summary of the Invention

[0003] The present disclosure applies niobium titanate and silicon active material to the negative electrode material, enabling it to adapt to a large current density while maintaining the integrity of the overall structure, avoiding problems such as short cycle life and poor safety due to structural damage of the battery, and further achieving the purpose of having a high energy density in a charge-discharge environment with a large current density.

[0004] According to the present disclosure, a composition comprising an active composition containing niobium titanate and silicon active material, wherein the niobium titanate contains niobium element, titanium element, and oxygen element, Niobium titanium oxide is Ti x Nb y O z or Ti(x-a) M1 a Nb (y-b) M2 b O (z-c) M3 c M1, M2, and M3 are doped elements. z ≤ 4x + 5y, 0 ≤ a <x、0≦b<y、0≦c<z And, When the weight ratio of niobium titanate in the active composition is Ptn and the weight ratio of silicon active material in the active composition is Ps, 2.0 ≦Ptn / Ps≦ 12.3 A composition satisfying the above conditions is provided.

[0005] According to the present disclosure, a negative electrode including the composition described in the previous paragraph is provided. <00T0120>

[0006] According to the present disclosure, a battery including the negative electrode described in the previous paragraph is provided.

[0007] According to the present disclosure, a composition including an active composition containing niobium titanate and a silicon active material, wherein the niobium titanate is a doped niobium titanate, and the doped niobium titanate contains niobium element, titanium element and oxygen element Doped niobium titanium oxide is, Ti (x-a) M1 a Nb (y-b) M2 b O [[ID=Y7]] (z-c) M3 c M1, M2, and M3 are doped elements. z ≤ 4x + 5y, 0 ≤ a <x、0≦b<y、0≦c<z Therefore, if we denote the weight ratio of niobium titanium oxide in the active composition as Ptn and the weight ratio of silicon active material in the active composition as Ps, 2.3 ≤ Ptn / Ps ≤ 15.0 The conditions are met A composition is provided.

[0008] According to this disclosure, a negative electrode comprising the composition described in the preceding paragraph is provided.

[0009] According to this disclosure, a battery including the negative electrode described in the preceding paragraph is provided. [Modes for carrying out the invention]

[0010] This disclosure provides compositions comprising an active composition and an inactive composition. The active composition may include niobium titanium oxide, a silicon active material, or a carbon active material. The inactive composition may be selected from the group consisting of polymers, carbon materials, metals, alloys, nonmetallic oxides, metal oxides, fluorides, organic compounds, adhesives, conductive agents, and additives.

[0011] This disclosure applies niobium titanium oxide and silicon active material to the negative electrode material. Niobium titanium oxide exhibits small changes in crystal volume during lithium insertion and possesses high mechanical stability, thus adapting to high current densities while maintaining the overall structural integrity and avoiding the problem of reduced battery cycle life due to structural damage. During rapid charge and discharge, niobium titanium oxide effectively avoids the formation of a solid electrolyte interface (SEI), reducing problems such as decreased electrical capacity due to lithium ion consumption and increased overall battery impedance. It also avoids the formation of lithium dendritic crystals, enhancing safety during battery use. The niobium and titanium elements contained in niobium titanium oxide, along with other suitable doping elements, provide multiple electron pairs through oxidation-reduction capabilities. When composed in appropriate proportions with silicon active material, it not only enhances the battery's rate performance and improves its charging efficiency but also achieves high energy density in high current density charge and discharge environments.

[0012] The niobium titanate described in the present disclosure includes undoped niobium titanate and doped niobium titanate. The composition components of the undoped niobium titanate include at least niobium element, titanium element and oxygen element. The undoped niobium titanate includes a plurality of compounds and may be further represented by the following chemical formula. Ti x Nb y O z However, z ≦ 4x + 5y. For example, TiNb2O7, Ti2Nb 10 O 29 、TiNb 14 O 37 and TiNb 24 O 62 etc. The crystal structure of the niobium titanate may be cubic, monoclinic, orthorhombic, ReO3-type lattice or layered structure, etc. The doped niobium titanate may be selected from those in which at least one compound of the above undoped niobium titanate is doped with at least one element and may be further represented by the following chemical formula. Ti (x-a) M1 a Nb (y-b) M2 b O (z-c) M3 c However, M1, M2 and M3 are doped elements, and 0 ≦ a < x, 0 ≦ b < y, 0 ≦ c < z. The structure can be changed by adjusting the doped element or the ratio of the doped element, and at least one inert composition can be selected to coat or fill the surface or pores of the niobium titanate. By changing the chemical properties of the niobium titanate by the doping method, it is helpful to reduce the difficulty of electron and ion movement and further increase the conductivity of the niobium titanate.

[0013] The doped elements described herein may be selected from any elements of Groups IA, IIA, IVB, VB, VIB, VIIB, VIIIB, IB, IIB, IIIA, IVA, VA, VIA, and VIA. Furthermore, at least one of Li, B, F, Na, Mg, Al, Si, P, S, Cl, Ca, V, Cr, Mn, Fe, Co, Ni, Zn, Ga, As, Br, Zr, Mo, Sb, I, Ta, W, or Bi may be selected. Doping with highly conductive or light elements helps to increase the conductivity of doped titanium niobium oxide, thereby enhancing the rapid charging performance of batteries and improving energy density. Doping titanium niobium oxide with appropriate elements helps to form energy levels with relatively low potential energies between the energy gaps of the doped titanium niobium oxide, reducing the difficulty of electron transfer and increasing the conductivity of the doped titanium niobium oxide. Furthermore, adding silicon active material with a high theoretical energy density helps to significantly improve the overall electrical capacity and energy density of the battery.

[0014] If we denote the weight ratio of niobium titanium oxide in the active composition as Ptn and the weight ratio of silicon active material in the active composition as Ps, 0.12 ≤ Ptn / Ps ≤ 99.0 The following conditions are met. The appropriate ratio of niobium titanium oxide and silicon active material helps to reinforce battery stability and improve energy density during high-current charging and discharging processes. 0.25≦Ptn / Ps≦60.0, 0.5≦Ptn / Ps≦40.0, 0.8≦Ptn / Ps≦35.0, 1.05≦Ptn / Ps≦30.0, 1.2≦Ptn / Ps≦25.0, 1.5≦Ptn / Ps≦20.0, 1.8≦Ptn / Ps≦18.0 or 2.0≦Ptn / Ps≦15.0 The following conditions may be met.

[0015] The weight ratio of niobium titanium oxide in the active composition is greater than the weight ratio of silicon active material in the active composition. Composing the niobium titanium oxide and silicon active material in appropriate proportions helps to improve the battery's charging efficiency and energy density.

[0016] The silicon active material described herein may be silicon, silicon oxide, silicon-carbon composite, silicon alloy, or any one of the above silicon active materials to which at least one inert composition has been added. The inert composition may form a mixture with the silicon active material, may form a chemical bond with the silicon active material, may form a core-shell structure with the silicon active material, or may form a film layer structure. The inert composition provides buffering, protection, and conductivity-enhancing functions, allowing it to adapt to rapid volume changes of the silicon active material during charging and discharging, maintaining the integrity of the overall structure, and avoiding the problem of increased impedance of the entire battery due to the silicon active material directly contacting the electrolyte and forming an interfacial film.

[0017] If the particle size of the silicon active material described in this disclosure is sD50, 10nm ≤ sD50 ≤ 10000nm This condition is met. By selecting a silicon active material with an appropriate particle size, it is possible to reduce the aggregation phenomenon of the silicon active material, thereby reducing stress due to the volume expansion of the silicon active material and saving costs. 20nm≦sD50≦99nm, 40nm≦sD50≦95nm, 60nm≦sD50≦90nm, 105nm≦sD50≦1000nm, 150nm≦sD50≦300nm, 450nm≦sD50≦700nm, 1200nm≦sD50≦8000nm, 1500nm≦sD50≦3000nm, 4000nm≦sD50≦6000nm, or 50nm≦sD50≦3000nm The following conditions may be met.

[0018] If the particle size of niobium titanium oxide is tnD50, 20nm ≤ tnD50 ≤ 9000nm This condition is met. By selecting niobium titanium oxide with an appropriate particle size, it is possible to shorten the time required for ion conduction and enhance rate performance. 40nm≦tnD50≦8000nm, 100nm≦tnD50≦6000nm, 150nm≦tnD50≦4500nm, 180nm≦tnD50≦4000nm, 200nm≦tnD50≦2000nm, 250nm≦tnD50≦1500nm, 280nm≦tnD50≦1000nm, 310nm≦tnD50≦900nm, or 350nm≦tnD50≦800nm The following conditions may be met.

[0019] If the particle size of the silicon active material is sD50 and the particle size of the niobium titanium oxide is tnD50, 0.01 ≤ tnD50 / sD50 ≤ 20.0 The following conditions are met. By selecting an appropriate particle size ratio of niobium titanium oxide and silicon active material, it is possible to improve the density and uniformity of the composition, and effectively enhance ionic conductivity and stability. 0.03≦tnD50 / sD50≦18.0, 0.05≦tnD50 / sD50≦15.0, 0.08≦tnD50 / sD50≦12.0, 0.10≦tnD50 / sD50≦10.0, 0.11≦tnD50 / sD50≦9.0, or 0.12≦tnD50 / sD50≦8.0 The following conditions may be met.

[0020] If we denote the weight ratio of niobium titanium oxide in the active composition as Ptn, the weight ratio of silicon active material in the active composition as Ps, and the weight ratio of carbon active material in the active composition as Pc, 0.01 ≤ Ptn / (Ps+Pc) ≤ 25.0 This condition is met. By adjusting the weight ratio of niobium titanium oxide and carbon-based materials in the composition, it is possible to increase the electrical capacity of the battery. 0.05≦Ptn / (Ps+Pc)≦22.0, 0.1≦Ptn / (Ps+Pc)≦20.0, 0.2≦Ptn / (P s+Pc)≦18.0, 1.0≦Ptn / (Ps+Pc)≦16.0, or 5.0≦Ptn / (Ps+Pc)≦15.0 The following conditions may be met.

[0021] The carbon active materials described herein may include graphite, graphene, carbon microspheres, hard carbon, soft carbon, conductive graphite (KS6, SFG6), acetylene black, Ketjenblack, carbon black (Super P), and carbon nanotubes (CNT).

[0022] The carbon materials described herein may include graphite, carbon microspheres, carbon fibers, hard carbon, soft carbon, conductive graphite, graphene, acetylene black, Ketjenblack, carbon black, and carbon nanotubes.

[0023] The adhesives described herein may be polyvinylidene fluoride (Poly(1,1-difluoroethylene); PVDF), styrene-butadiene rubber (SBR), polyethylene (Poly(methylene); PE), polyvinyl alcohol (Poly(ethenol); PVA), polyvinylpyrrolidone (Poly(1-ethenylpyrrolidin-2-one); PVP), polypropylene (Poly(1-methylethylene); PP), polyacrylonitrile (Poly(1-acrylonitrile); PAN), carboxymethyl cellulose (Carboxymethyl cellulose; CMC), polytetrafluoroethylene (Poly(1,1,2,2-tetrafluoroethylene); PTFE), ethylene propylene diene monomer (EPDM), chlorosulfonated polyethylene (Hypalon polyethylene rubber; CSM), or alginic acid linearly polymerized with monouronic acid.

[0024] The conductive agents described herein may be graphite, conductive graphite, graphene, acetylene black, Ketjenblack, carbon black, carbon nanotubes, carbon microspheres, carbon fibers, hard carbon, soft carbon, aluminum powder, nickel powder, titanium dioxide, potassium titanate (PHT), or combinations thereof.

[0025] The additives described herein may be carbonate compounds, cyclic diesters, ether group-containing cyclic compounds, aromatic compounds, phosphorus-containing compounds, boron-containing compounds, inorganic oxides, or combinations thereof. Adding an appropriate amount of additive can help improve battery performance, for example, by improving the composition of the SEI film, enhancing performance at high temperature and high voltage, improving ion conductivity, reducing electrolyte impedance, improving cycle stability, stabilizing the integrity of the positive and negative electrode materials, and improving electrochemical stability.

[0026] The negative electrode materials described in this disclosure include niobium titanium oxide, silicon active material, carbon active material, carbon material, lithium-containing metal compound, and lithium-containing metal oxide (Li4Ti5O 12 ), metallic lithium, or a combination thereof.

[0027] The metal salts described in this disclosure may include inorganic lithium acid salts such as LiPF6, LiBF4, LiSbF6, LiAsF6, LiClO4, LiC4BO8, LiTFSI, LiFSI, LiNO3, LiGaCl4, etc., fluorine-containing lithium sulfonate salts such as LiCF3SO3, LiN(C2F5SO2)2, LiN(CF3SO2)2, LiC(CF3SO2)3, LiBF2(C2O4)(LiDFOB), LiB(C2O4)2(LiBOB), or combinations thereof, and the above metal salts may include multiple different oxidation states.

[0028] The positive electrode material described herein may be a lithium composite metal oxide containing lithium or at least one metal. For example, lithium iron phosphate (LiFePO4), lithium manganese oxide (LiMnO2, LiMn2O4), lithium cobalt oxide (LiCoO2), lithium nickel oxide (LiNiO2), lithium nickel cobalt oxide (LiNiCoO2), lithium nickel manganese oxide (LiNiMnO4), lithium manganese cobalt oxide (LiCoMnO2, LiCoMnO4), lithium nickel manganese cobalt oxide (LiNiCoMnO2, LiNiCoMnO4), or a combination thereof, and the lithium composite metal oxide may include multiple different oxidation states.

[0029] The electrolyte described in this disclosure may be composed of metal salts, additives, and organic solvents, etc. The proportion of organic solvent may be greater than the proportion of additives, and the electrolyte state may be liquid, colloidal, or solid. The additive electrolyte and the organic solvent may be physically mixed, and at least one of the following additives or organic solvent monomers may be selected as the polymerization precursor.

[0030] The organic solvents described herein may be carbonate-based, carboxylic acid ester-based, ether-based, sulfur-containing compounds, or combinations thereof, and these organic solvents may be used as additives.

[0031] The organic solvents described herein may contain polymerizable olefin groups in their structure and may serve as monomers for the second structural precursor. Examples include vinylene carbonate (2H-1,3-Dioxol-2-one; Vinylene carbonate; VC), vinylethylene carbonate (4-Vinyl-1,3-dioxolan-2-one; Vinylethylene carbonate; VEC), trithiovinylene carbonate (1,3-Dithiole-2-thione; Vinylene trithiocarbonate), sulfolene (2,5-Dihydrothiophene-1,1-dioxide), divinylsulfonylethene, 1-propene-1,3-sultone, additives of ether group-containing cyclic compounds, or additives of aromatic compounds.

[0032] The carbonate esters described herein may be compounds in which some or all of the hydrogen atoms of the hydroxyl group in a carbonate molecule are substituted with alkyl groups, and may be divided into cyclic carbonates and linear carbonates. Linear carbonates may include dimethyl carbonate (DMC), diethyl carbonate (DEC), dipropyl carbonate (DPC), ethyl methyl carbonate (EMC), methyl propyl carbonate (MPC), ethyl propyl carbonate (EPC), and methyl-2,2,2-trifluoroethyl carbonate (FEMC).Cyclic carbonates include ethylene carbonate (1,3-Dioxolan-2-one; EC), propylene carbonate (4-Methyl-1,3-dioxolan-2-one; PC), trimethylene carbonate (1,3-Dioxan-2-one; TMC), 1,2-butylene carbonate (4-Ethyl-1,3-dioxolan-2-one; 1,2-Butylene carbonate), cis-2,3-butylene carbonate ((4R,5S)-4,5-Dimethyl-1,3-dioxolan-2-one; cis-2,3-Butylene carbonate), 1,2-pentylene carbonate, and 2,3-pentylene carbonate. It may contain (carbonate), vinylene carbonate, vinylethylene carbonate, fluoroethylene carbonate (4-Fluoro-1,3-dioxolan-2-one; Fluoroethylene carbonate; FEC), difluoroethylene carbonate (trans-4,5-Difluoro-1,3-dioxolan-2-one; Difluoroethylene carbonate; DFEC), trithiovinylene carbonate, or a combination thereof.

[0033] The carboxylic acid ester organic solvents described herein are prepared by the esterification reaction of alcohols and carboxylic acids, and may be methyl acetate, ethyl acetate, propyl acetate, methyl propionate, ethyl propionate, propyl propionate, methyl butyrate, ethyl butyrate, lactone, or a combination thereof. Lactone may be further described as containing a 1-oxacycloalkan-2-one structure. This refers to a compound containing a hydroxyl group and a carboxylic acid, which condense intramolecularly to form a cyclic carboxylic acid ester monomer, and multiple combinations are possible depending on the position of the hydroxyl group forming the ring and the number of carbon atoms in the ring. It may contain α-acetolactone (Oxiran-2-one), β-propiolactone (Oxetan-2-one), γ-butyrolactone (Oxolan-2-one), γ-valerolactone (5-Methyloxolan-2-one), σ-valerolactone (Oxan-2-one), γ-caprolactone (5-Ethyloxolan-2-one), ε-caprolactone (Oxepan-2-one), δ-gluconolactone (D-Glucono-1,5-lactone), or a combination thereof.

[0034] The ether-based organic solvents described herein may be tetrahydrofuran (Oxolane; THF), 2-methyltetrahydrofuran (2-Methyloxolane; 2-MeTHF), 1,3-dioxolane (1,3-Dioxolane; DOL), 4-methyl-1,3-dioxolane (4-Methyl-1,3-dioxolane; 4-MeDOL), dimethoxymethane (Dimethoxymethane; DMM), 1,2-dimethoxyethane (1,2-Dimethoxyethane; DME), 2,2-dimethoxypropane (2,2-Dimethoxypropane; DMP), 1,2-bis(2-cyanoethoxy)ethane (1,2-Bis(2-cyanoethoxy)ethane; DENE), diglym (1-Methoxy-2-(2-methoxyethoxy)ethane; DG), or combinations thereof.

[0035] The organic solvents containing sulfides described in this disclosure may be divided into sulfonyl group compounds (sulfone group; -(O=)S(=O)-) and sulfonate ester compounds (sulfonate group; -SO2O-). The sulfonyl group-containing compound may include sulfolene and divinyl sulfone, and the sulfonic acid ester compound may be further subdivided into mesylate (CH3SO2O-), trifluoromethanesulfonate (CF3SO2O-), p-toluenesulfonyl group (Tosyl), and may include ethyl methanesulfonyloxyethane, methyl 4-methylbenzenesulfonate, 1,3-propanesultone (Oxathiolane 2,2-dione), 1-propene-1,3-sultone, 1,3,2-dioxathiane-2,2-dioxide, or a combination thereof.

[0036] The lactone cyclic esters described herein may be multimembered ring diester monomers formed by the esterification condensation of two identical or different compounds containing a hydroxycarboxylic acid. They may include glycoides (1,4-Dioxane-2,5-dione), lactides (3,6-Dimethyl-1,4-dioxane-2,5-dione), or combinations thereof. Based on stereoisomers formed by differences in the spatial arrangement of atoms, lactides may be further subdivided into LL-lactide ((R,R)-3,6-Dimethyl-1,4-dioxane-2,5-dione; LL-lactide), DD-lactide ((S,S)-3,6-Dimethyl-1,4-dioxane-2,5-dione; DD-lactide), and DL-lactide ((meso)-3,6-Dimethyl-1,4-dioxane-2,5-dione; DL-lactide). Alternatively, hydroxyl group-containing carboxylic acid compounds can be directly copolymerized to form polymers without requiring a ring-opening reaction, and may include 2-hydroxyacetic acid (glycolic acid), 3-hydroxypropanoic acid (lactic acid), 4-hydroxybutanoic acid, 5-hydroxypentanoic acid, or combinations thereof.

[0037] The additives of the ether group-containing cyclic compounds described herein may be crown ethers having an ethyleneoxy group (-CH2CH2O-) as the main repeating unit structure. 9-Crown-3 (1,4,7-Trioxonane; 9-Crown-3), 12-Crown-4 (1,4,7,10-Tetraoxacyclododecane; 12-Crown-4), 15-Crown-5 (1,4,7,10,13-Pentaoxacyclopentadecane; 15-Crown-5), 18-Crown-6 (1,4,7,10,13,6-Hexaoxacyclooctadecane; 18-Crown-6), 21-Crown-7 (1,4,7,10,13,16,19-Heptaoxacycloheneicosane; 21-Crown-7), Dibenzo-18-Crown-6 (6,7,9,10,17,18,20,21-Octahydrodibenzo[b,k][1,4,7,10,13,16] This may include hexaoxacyclooctadecine (Dibenzo-18-crown-6), diaza-18-crown-6 (1,4,10,13-Tetraoxa-7,16-diazacyclooctadecane (Diaza-18-crown-6)), or a combination thereof.

[0038] The aromatic compound additives described herein may include methoxybenzene, 1-ethynyl-4-methoxybenzene, tert-butylbenzene, fluorobenzene, 1,2-difluorobenzene, 1,1'-oxydibenzene, terphenyl (1,4-diphenylbenzene), 4-tert-butyl-2-fluoroaniline, N-[3-(trimethoxysilyl)propyl]aniline, or combinations thereof.

[0039] The phosphorus-containing compound additives described in this disclosure may be tris(trimethylsilyl) phosphite (TMSPi), tris(2,2,2-trifluoroethyl) phosphite, triphenyl phosphite, ethoxy(pentafluoro)cyclotriphosphazene (1,3,5,2,4,6-Triazatriphosphorine-2-ethoxy-2,4,4,6,6-pentafluoro-2,2,4,4,6,6-hexahydro), or a combination thereof.

[0040] The additives for the boron-containing compounds described herein may be trimethyl borate, tris(trimethylsilyl) borate, trimethylboroxine (2,4,6-Trimethyl-1,3,5,2,4,6-trioxatriborinane), or a combination thereof.

[0041] The inorganic oxide additives described in this disclosure may be composite materials such as lithium lanthanum zirconium oxide (LiLaZrO), lithium lanthanum zirconium tantalum oxide (LiLaZrTaO), lithium lanthanum titanium oxide (LiLaTiO), lithium phosphate (LiPO), lithium fluorophosphate (LiPOF), lithium titanium phosphate (LiTiPO), lithium aluminum germanium phosphate (LiAlGeP), lithium aluminum titanium oxide (LiAlTiPO), lithium germanium phosphate sulfur oxide (LiGePSO), lithium tin phosphate sulfur oxide (LiSnPSO), lead zirconium titanium oxide (PbZrTiO), lead lanthanum zirconium titanium oxide (PbLaZrTiO), and barium titanium oxide (BaTiO). The above-mentioned inorganic oxide additive may include multiple different oxidation states, or may be Al2O3, TiO2, SiO2, SnO2, NiO, ZnO, CaO, MgO, ZrO2, CeO2, Y2O3, etc., and can reduce the crystallinity of the polymer electrolyte, further increase the ionic conductivity and the physical and mechanical strength of the electrolyte, and contribute to extending the battery cycle life.

[0042] The separator described in this disclosure may be a thin film having a porous structure, and may include a single or multilayer film of polyolefins such as polyethylene, polypropylene, polyethylene terephthalate (PET), acrylonitrile-butadiene-styrene copolymer (ABS), epoxy resin, polyamide, polyester fiber, or an inorganic ceramic composite thin film or a combination thereof, which has at least one of the following on its surface: Mg(OH)2, MgO, BaSO4, SnO2, NiO, CaO, Al2O3, ZnO, SiO2, TiO2, etc. The inorganic ceramic composite thin film may contain multiple different oxidation states.

[0043] All related arrangements of niobium titanium oxide, silicon active material, and carbon active material described herein can be manufactured into electrode plates based on their respective proportions and subjected to battery charge-discharge testing. This disclosure shows only the manufacturing proportions and battery charge-discharge testing for some related arrangements; if data is unavailable or cannot be calculated, the cell in the table is marked with a "-".

[0044] This disclosure provides a negative electrode containing the aforementioned composition.

[0045] This disclosure provides a battery including the aforementioned negative electrode.

[0046] If C2VMax is the maximum value between the discharge volumetric capacity at the 1st cycle and the discharge volumetric capacity at the 15th cycle when charging and discharging the battery with an electric charge of 2C, 100mAh / cm 3 ≤C2VMax ≤800mAh / cm 3 This condition is met. Measuring the maximum electrical capacity for the first 15 cycles helps to determine the battery's capacity after it has reached a stable state. 120mAh / cm 3 ≤C2VMax ≤750mAh / cm 3 , 140mAh / cm² 3 ≤C2VMax ≤720mAh / cm 3 , 160mAh / cm² 3 ≤C2VMax ≤700mAh / cm 3 , 180mAh / cm² 3 ≤C2VMax ≤680mAh / cm 3 , 200mAh / cm² 3 ≤C2VMax ≤650mAh / cm 3 , 220mAh / cm² 3 ≤C2VMax ≤630mAh / cm 3 , or 230mAh / cm² 3 ≤C2VMax ≤500mAh / cm 3 The following conditions may be met.

[0047] If the discharge volumetric capacity at the 60th cycle when charging and discharging the battery with an electric charge of 2C is C2V60, then 100mAh / cm 3 ≤C2V60 ≤800mAh / cm 3 This condition is met. Measuring that the battery's electrical capacity reaches a high level after multiple cycles is useful for evaluating the battery's capacity and performance. 120mAh / cm 3 ≤C2V60 ≤ 750mAh / cm² 3 , 140mAh / cm² 3 ≤C2V60 ≤ 720mAh / cm 3 , 160mAh / cm² 3 ≤C2V60 ≤ 700mAh / cm 3 , 180mAh / cm² 3 ≤C2V60 ≤ 680mAh / cm 3 , 200mAh / cm² 3 ≤C2V60 ≤ 650mAh / cm 3 , 220mAh / cm² 3 ≤C2V60 ≤ 630mAh / cm 3 , or 230mAh / cm² 3 ≤C2V60 ≤ 500mAh / cm 3 The following conditions may be met.

[0048] If we define C2V5 as the discharge volumetric capacity after 5 cycles when charging and discharging the battery with an electric charge of 2C, and C2V10 as the discharge volumetric capacity after 10 cycles when charging and discharging the battery with an electric charge of 2C, 0.70 ≤ C2V10 / C2V5 This condition is met. Comparing the difference in electrical capacity after the 5th cycle and after a short cycle count helps determine the battery's durability. 0.75≦C2V10 / C2V5≦1.50, 0.80≦C2V10 / C2V5≦1.30, 0.85≦C2V10 / C2V5≦1.20, 0.90≦C2V10 / C2V5≦1.10, or 0.95≦C2V10 / C2V5≦1.05 The following conditions may be met.

[0049] If we define C2V5 as the discharge volumetric capacity at the 5th cycle when charging and discharging the battery with an electric charge of 2C, and C2V20 as the discharge volumetric capacity at the 20th cycle when charging and discharging the battery with an electric charge of 2C, 0.60 ≤ C2V20 / C2V5 This condition is met. Comparing the difference in electrical capacity after the 5th cycle and after the intermediate cycle count helps determine the battery's durability. 0.70≦C2V20 / C2V5≦1.50, 0.75≦C2V20 / C2V5≦1.40, 0.80≦C2V20 / C2V5≦1.30, 0.85≦C2V20 / C2V5≦1.20, 0.90≦C2V20 / C2V5≦1.10, or 0.95≦C2V20 / C2V5≦1.05 The following conditions may be met.

[0050] If n85C2E15 is the total number of cycles that satisfy the Coulomb efficiency for the first 15 cycles when charging and discharging a battery with an electric charge of 2C, then 10 ≤ n85C2E15 ≤ 15 This condition is met. The high level of Coulomb efficiency in the early cycle counts helps to reduce the impact of lithium loss on capacity retention. 11≦n85C2E15≦15, 12≦n85C2E15≦15, 13≦n85C2E15≦15, or 14≦n85C2E15≦15 The following conditions may be met.

[0051] If n85C2E50 is the total number of cycles that satisfy the Coulomb efficiency for the first 50 cycles when charging and discharging a battery with a charge of 2C, then 40≦n85C2E50≦50 The following conditions are met. The high level of Coulomb efficiency across long cycle counts allows it to be used as a quantitative indicator of battery reversibility. 42≦n85C2E50≦50, 44≦n85C2E50≦50, 45≦n85C2E50≦50, 46≦n85C2E50≦50, 47≦n85C2E50≦50, 48≦n85C2E50≦50, or 49≦n85C2E50≦50 The following conditions may be met.

[0052] If we define aC2E15 as the average Coulomb efficiency over the first 15 cycles when charging and discharging a battery with an electrical charge of 2C, 80% ≤ aC2E15 ≤ 110% This condition is met. Maintaining a relatively high average Coulomb efficiency during early charge and discharge helps the battery achieve high stability in later cycles. 82%≦aC2E15≦108%, 85%≦aC2E15≦105%, 87%≦aC2E15≦103%, 90%≦aC2E15≦101%, or 92%≦aC2E15≦100% The following conditions may be met.

[0053] If we define aC2E50 as the average Coulomb efficiency over the first 50 cycles when charging and discharging a battery with an electrical charge of 2C, 75% ≤ aC2E50 ≤ 110% This condition is met. The discharge capacity and charge capacity show good consistency across multiple cycle counts, and by maintaining a high average Coulomb efficiency, it helps extend the battery's high-efficiency performance. 80%≦aC2E50≦108%, 82%≦aC2E50≦106%, 85%≦aC2E50≦105%, 87%≦aC2E50≦103%, 90%≦aC2E50≦101%, 91%≦aC2E50≦100%, or 92%≦aC2E50≦98% The following conditions may be met.

[0054] If we let C1V1 be the discharge volumetric capacity in the first cycle when charging and discharging the battery with an electric charge of 1C, and C2V1 be the discharge volumetric capacity in the first cycle when charging and discharging the battery with an electric charge of 2C, 0.50 ≤ C2V1 / C1V1 This condition is met. As can be seen by comparing the electrical capacity when charging and discharging with high current and when charging and discharging with low current, the active composition helps to enhance the rate performance of the battery as a negative electrode active material. 0.60≦C2V1 / C1V1≦1.50, 0.70≦C2V1 / C1V1≦1.40, 0.75≦C2V1 / C1V1≦1.30, 0.80≦C2V1 / C1V1≦1.25, 0.85≦C2V1 / C1V1≦1.20, or 0.90≦C2V1 / C1V1≦1.18 The following conditions may be met.

[0055] If C2GMax is the maximum value between the discharge gravimetric capacity at the 1st cycle and the discharge gravimetric capacity at the 15th cycle when charging and discharging the battery with an electric charge of 2C, 100mAh / g ≤ C2GMax ≤ 800mAh / g This condition is met. Measuring the maximum electrical capacity during the first 15 cycles helps in observing the battery's capacity after it has reached a stable state. 120mAh / g ≤ C2GMax ≤ 750mAh / g, 140mAh / g ≤ C2GMax ≤ 700mAh / g, 160mAh / g ≤ C2GMax ≤ 680mAh / g, 180mAh / g ≤ C2GMax ≤ 650mAh / g, 200mAh / g ≤ C2GMax ≤ 630mAh / g, or 250mAh / g ≤ C2GMax ≤ 600mAh / g The following conditions may be met.

[0056] If the gravimetrically charged capacity of a battery at the 60th cycle when charging and discharging it with an electric charge of 2C is C2G60, then 100mAh / g ≤ C2G60 ≤ 800mAh / g This condition is met. Measuring that the battery's electrical capacity reaches a high level after multiple cycles helps evaluate key indicators of battery capacity and performance. 110mAh / g ≤ C2G60 ≤ 750mAh / g, 120mAh / g ≤ C2G60 ≤ 700mAh / g, 130mAh / g ≤ C2G60 ≤ 680mAh / g, 140mAh / g ≤ C2G60 ≤ 650mAh / g, 150mAh / g ≤ C2G60 ≤ 630mAh / g, or 180mAh / g ≤ C2G60 ≤ 600mAh / g The following conditions may be met.

[0057] If we define C2V5 as the discharge volumetric capacity at the 5th cycle when charging and discharging the battery with an electric charge of 2C, and C2V60 as the discharge volumetric capacity at the 60th cycle when charging and discharging the battery with an electric charge of 2C, 0.50 ≤ C2V60 / C2V5 This condition is met. Comparing the difference in electrical capacity after the 5th cycle and after a long cycle count can be useful in determining the battery's lifespan. 0.60≦C2V60 / C2V5≦1.50, 0.70≦C2V60 / C2V5≦1.40, 0.75≦C2V60 / C2V5≦1.30, 0.80≦C2V60 / C2V5≦1.20, 0.85≦C2V60 / C2V5≦1.15, 0.90≦C2V60 / C2V5≦1.10, or 0.95≦C2V60 / C2V5≦1.05 The following conditions may be met.

[0058] If n90C2E15 is the total number of cycles that satisfy the Coulomb efficiency of the first 15 cycles when charging and discharging a battery with an electric charge of 2C, then 8 ≤ n90C2E15 ≤ 15 This condition is met. The high level of Coulomb efficiency in the early cycle counts helps the battery maintain stability in later cycles. 9≦n90C2E15≦15, 10≦n90C2E15≦15, 11≦n90C2E15≦15, 12≦n90C2E15≦15, 13≦n90C2E15≦15, or 14≦n90C2E15≦15 The following conditions may be met.

[0059] If n90C2E50 is the total number of cycles that satisfy the Coulomb efficiency for the first 50 cycles when charging and discharging a battery with an electric charge of 2C, then 30 ≤ n90C2E50 ≤ 50 This condition is met. The high level of Coulomb efficiency across long cycle counts helps maintain a balance between lithium ion insertion and removal from the active material, thereby extending the battery life. 33≦n90C2E50≦50, 35≦n90C2E50≦50, 38≦n90C2E50≦50, 40≦n90C2E50≦50, 41≦n90C2E50≦49, 42≦n90C2E50≦48, or 43≦n90C2E50≦47 The following conditions may be met.

[0060] If we let C2V1 be the discharge volumetric capacity in the first cycle when charging and discharging the battery with an electric charge of 2C, and C4V1 be the discharge volumetric capacity in the first cycle when charging and discharging the battery with an electric charge of 4C, 0.50 ≤ C4V1 / C2V1 This condition is met. As can be seen by performing battery charge / discharge tests with a large current, the active composition has high chemical stability and high ion transfer capability as a negative electrode active material, which helps to reinforce safety during rapid charging of the battery. 0.60≦C4V1 / C2V1≦1.50, 0.70≦C4V1 / C2V1≦1.40, 0.75≦C4V1 / C2V1≦1.30, 0.80≦C4V1 / C2V1≦1.20, 0.85≦C4V1 / C2V1≦1.15, or 0.90≦C4V1 / C2V1≦1.10 The following conditions may be met.

[0061] The definition of battery cycle count as described in this disclosure assumes that the battery is in a commercially available product state. The first test in this state is defined as the first cycle as described in this disclosure. Completing one discharge and one charge test constitutes one cycle count, and the cycle count accumulates in this manner.

[0062] The electrical capacity described in this disclosure may be measured by measuring the charging capacity and discharging capacity of the battery. The method for calculating the electrical capacity is volumetric capacity (mAh / cm³). 3 Volumetric capacity may be divided into volumetric capacity and gravimetric capacity (mAh / g). Volumetric capacity represents the electrical capacity that can be provided by the plates per cubic centimeter in a battery, and the volume of the current collector must be subtracted when calculating volumetric capacity. Gravimetric capacity represents the electrical capacity that can be provided by the plates per gram in a battery, and the weight of the current collector must be subtracted when calculating gravimetric capacity. The plates may be positive or negative plates, and the current collector has a base material made of metal foil (e.g., aluminum foil, copper foil).

[0063] The C-rate (C) described in this disclosure can represent the amount of electricity required for a battery to be completely discharged in one hour. C may be the unit of electricity used to charge and discharge a battery.

[0064] Regarding the voltage range for battery measurement described in this disclosure, an appropriate voltage range can be selected based on the oxidation-reduction potential of the positive and negative electrode materials. The voltage range can be selected from 0V to 5.0V, and preferably from 2.5V to 4.5V.

[0065] The discharge volumetric capacity described herein may be expressed as CiVj, and the discharge gravimetric capacity may be expressed as CiGj. i represents charging and discharging in units of electric force (C), and j represents the current number of charge-discharge cycles of the battery.

[0066] The total number of times the Coulomb efficiency described in this disclosure satisfies a specific percentage range may be expressed as nxCyEz, where x represents the lower limit of this specific percentage range, y represents charging and discharging in units of C, and z represents the number of charge-discharge cutoff cycles of the battery.

[0067] The average Coulomb efficiency described in this disclosure may be expressed as aCyEz, where y represents charging and discharging in units of electric charge (C), and z represents the number of charge-discharge cutoff cycles of the battery.

[0068] With respect to the battery described in this disclosure, if we define the discharge volumetric capacity at the 5th cycle when charging and discharging the battery with an electric charge of 2C as C2V5, and the discharge volumetric capacity at the 500th cycle when charging and discharging the battery with an electric charge of 2C as C2V500, 0.50 ≤ C2V500 / C2V5 ≤ 1.50 This condition is met. Comparing the difference in electrical capacity after the 5th cycle and after a long cycle count can be useful in determining the battery's lifespan. 0.60≦C2V500 / C2V5≦1.30, 0.70≦C2V500 / C2V5≦1.10, 0.80≦C2V500 / C2V5≦1.00, or 0.85≦C2V500 / C2V5≦0.95 The following conditions may be met.

[0069] Regarding the battery described in this disclosure, if we define the discharge volumetric capacity at the 5th cycle when charging and discharging the battery with an electric charge of 4C as C4V5, and the discharge volumetric capacity at the 500th cycle when charging and discharging the battery with an electric charge of 4C as C4V500, 0.40 ≤ C4V500 / C4V5 ≤ 1.50 This condition is met. Comparing the difference in electrical capacity after the 5th cycle, which tests the battery with a large current, with that after a long number of cycles is useful for evaluating the battery's capacity and performance. 0.50≦C4V500 / C4V5≦1.40, 0.60≦C4V500 / C4V5≦1.30, 0.70≦C4V500 / C4V5≦1.20, 0.80≦C4V500 / C4V5≦1.00, or 0.85≦C4V500 / C4V5≦0.95 The following conditions may be met.

[0070] With respect to the battery described in this disclosure, if we define the discharge volumetric capacity at the 5th cycle when charging and discharging the battery with an electric charge of 10C as C10V5, and the discharge volumetric capacity at the 500th cycle when charging and discharging the battery with an electric charge of 10C as C10V500, 0.30 ≤ C10V500 / C10V5 ≤ 1.50 This condition is met. Comparing the difference in electrical capacity after the 5th cycle, which tests the battery with a large current, with that after a long number of cycles is useful for evaluating the battery's capacity and performance. 0.40≦C10V500 / C10V5≦1.40, 0.50≦C10V500 / C10V5≦1.30, 0.60≦C10V500 / C10V5≦1.20, 0.70≦C10V500 / C10V5≦1.10, 0.80≦C10V500 / C10V5≦1.00, or 0.85≦C10V500 / C10V5≦0.95 The following conditions may be met.

[0071] Regarding the battery described in this disclosure, if n85C2E500 is defined as the total number of cycles in which the Coulomb efficiency for the first 500 cycles of charging and discharging the battery with an electric charge of 2C is greater than 85% but less than 110%, then 400≦n85C2E500≦500 The following conditions are met. The high level of Coulomb efficiency across long cycle counts allows it to be used as a quantitative indicator of battery reversibility. 420≦n85C2E500≦495, 440≦n85C2E500≦490, 450≦n85C2E500≦485, or 460≦n85C2E500≦480 The following conditions may be met.

[0072] Regarding the battery described in this disclosure, if n90C2E500 is defined as the total number of cycles in which the Coulomb efficiency for the first 500 cycles of charging and discharging the battery with an electric charge of 2C is greater than 90% but less than 110%, then 350≦n90C2E500≦500 The following conditions are met. The high level of Coulomb efficiency across long cycle counts allows it to be used as a quantitative indicator of battery reversibility. 370≦n90C2E500≦495, 385≦n90C2E500≦490, 400≦n90C2E500≦485, or 420≦n90C2E500≦480 The following conditions may be met.

[0073] Regarding the battery described in this disclosure, if n85C4E500 is defined as the total number of cycles in which the Coulomb efficiency for the first 500 cycles of charging and discharging the battery with an electrical charge of 4C is greater than 85% but less than 110%, then 350≦n85C4E500≦500 The following conditions are met. When performing charge-discharge tests with large currents, the Coulomb efficiency over long cycle counts reaches a high level, which can be used as a quantitative indicator of battery reversibility. 370≦n85C4E500≦495, 385≦n85C4E500≦490, 400≦n85C4E500≦485, or 420≦n85C4E500≦480 The following conditions may be met.

[0074] Regarding the battery described in this disclosure, if n90C4E500 is defined as the total number of cycles in which the Coulomb efficiency for the first 500 cycles of charging and discharging the battery with an electrical charge of 4C is greater than 90% but less than 110%, then 350≦n90C4E500≦500 The following conditions are met. When performing charge-discharge tests with large currents, the Coulomb efficiency over long cycle counts reaches a high level, which can be used as a quantitative indicator of battery reversibility. 370≦n90C4E500≦495, 385≦n90C4E500≦490, 400≦n90C4E500≦485, or 420≦n90C4E500≦480 The following conditions may be met.

[0075] Regarding the battery described in this disclosure, if n85C10E500 is the total number of cycles in which the Coulomb efficiency for the first 500 cycles when charging and discharging the battery with an electrical charge of 10C is greater than 85% but less than 110%, then 350≦n85C10E500≦500 The following conditions are met. When performing charge-discharge tests with large currents, the Coulomb efficiency over long cycle counts reaches a high level, which can be used as a quantitative indicator of battery reversibility. 370≦n85C10E500≦495, 385≦n85C10E500≦490, 400≦n85C10E500≦485, or 420≦n85C10E500≦480 The following conditions may be met.

[0076] Regarding the battery described in this disclosure, if n90C10E500 is the total number of cycles in which the Coulomb efficiency for the first 500 cycles when charging and discharging the battery with an electric charge of 10C is greater than 90% but less than 110%, then 350≦n90C10E500≦500 The following conditions are met. When performing charge-discharge tests with large currents, the Coulomb efficiency over long cycle counts reaches a high level, which can be used as a quantitative indicator of battery reversibility. 370≦n90C10E500≦495, 385≦n90C10E500≦490, 400≦n90C10E500≦485, or 420≦n90C10E500≦480 The following conditions may be met.

[0077] Regarding the battery described in this disclosure, if we define aC2E500 as the average value of the Coulomb efficiency over the first 500 cycles when charging and discharging the battery with an electric charge of 2C, 80% ≤ aC2E500 ≤ 110% This condition is met. The discharge capacity and charge capacity show good consistency across multiple cycle counts, and by maintaining a high average Coulomb efficiency, it helps extend the battery's high-efficiency performance. 85% ≤ aC2E500 ≤ 105%, or 90% ≤ aC2E500 ≤ 100% The following conditions may be met.

[0078] Regarding the battery described in this disclosure, if we define aC4E500 as the average Coulomb efficiency over the first 500 cycles when charging and discharging the battery with an electrical charge of 4C, 80% ≤ aC4E500 ≤ 110% The following conditions are met. When performing charge-discharge tests with large currents, the discharge capacity and charge capacity show good agreement over multiple cycle counts, and by maintaining a high average value of Coulomb efficiency, it helps extend the battery's high-efficiency performance. 85% ≤ aC4E500 ≤ 105%, or 90% ≤ aC4E500 ≤ 100% The following conditions may be met.

[0079] Regarding the battery described in this disclosure, if we define aC10E500 as the average value of the Coulomb efficiency over the first 500 cycles when charging and discharging the battery with an electrical charge of 10C, 80% ≤ aC10E500 ≤ 110% The following conditions are met. When performing charge-discharge tests with large currents, the discharge capacity and charge capacity show good agreement over multiple cycle counts, and by maintaining a high average value of Coulomb efficiency, it helps extend the battery's high-efficiency performance. 85% ≤ aC10E500 ≤ 105%, or 90% ≤ aC10E500 ≤ 100% The following conditions may be met.

[0080] The volumetric energy density described in this disclosure may be calculated based on the following formula. Volumetric energy density (Wh / L) = Discharge capacity (Ah) × Nominal voltage (V) / Total battery volume (L).

[0081] The gravimetric energy density described in this disclosure may be calculated based on the following formula. Gravimetric energy density (Wh / kg) = Discharge capacity (Ah) × Nominal voltage (V) / Total battery weight (kg).

[0082] Regarding the battery described in this disclosure, if the discharge volume energy density of the battery in the 5th cycle is vE5, 500Wh / L ≤ vE5 ≤ 900Wh / L This condition is met. The high level of the battery's discharge volumetric energy density contributes to its diverse applications. 550Wh / L ≤ vE5 ≤ 850Wh / L, or 600Wh / L ≤ vE5 ≤ 800Wh / L The following conditions may be met.

[0083] Regarding the battery described in this disclosure, if the gravimetric energy density of the battery after 5 cycles is gE5, 180 Wh / kg ≤ gE5 ≤ 450 Wh / kg This condition is met. The high level of the battery's discharge gravimetric energy density contributes to its diverse applications. 200 Wh / kg ≤ gE5 ≤ 400 Wh / kg, or 250 Wh / kg ≤ gE5 ≤ 350 Wh / kg The following conditions may be met.

[0084] The particle size described in this disclosure may be measured by measuring the amplitude over time of light scattered by particles in Brownian motion using dynamic light scattering, and the size of the particle size may be determined based on the Stokes-Einstein equation. The equation is as follows: D = kT / (3πηDf) However, D is the particle size (in m), k is the Boltzmann constant (in J / K), T is the absolute temperature (in K), and η is the viscosity of the solvent (in kg × m). -1 ×s -1 ) and Df is the diffusion coefficient (unit m 2 ×s -1 )

[0085] The particle size distribution described in this disclosure represents the particle size distribution of various different sizes of particles in the object being measured. Based on the proportion of each particle size distribution and the percentage of the cumulative amount relative to the volume, a cumulative particle size distribution function can be obtained. For example, if the particle size at which the percentage of the cumulative particle size distribution reaches 50% is defined as D50, it can be explained that the particle size of 50% of the particles in the object being measured is smaller than the particle size of D50. D10 and D90 are determined by analogy in the same way, and unless otherwise specified, D50 is used as the particle size determination criterion.

[0086] The core particle size described in this disclosure can be measured based on the following Scherrer equation by analyzing the diffraction peak {111} of silicon crystal particles using an X-ray diffractometer. L = (κ × λ) / (βcos(θ / 2)) However, L is the particle size of the silicon crystal grain (in nm), κ is the shape factor (approximately 0.9, but varies depending on the actual shape of the crystal), β is the full width at half maximum of the diffraction peak {111} (in radians), and θ is the position of the diffraction peak {111}.

[0087] The negative electrode plates described in this disclosure may be manufactured by methods such as single-layer or double-layer coating, vacuum coating, or composite structure.

[0088] The roughness described in this disclosure is the arithmetic mean height of the surface based on the surface texture parameter Sa (μm) of ISO 251781. The area of ​​the region where roughness is measured is at least 10,000 μm². 2 Set to a larger value, the average plane height is the arithmetic mean of the heights of each point at coordinate Z(x,y) within the area of ​​the region. Sa is the average of the absolute differences in height between each point at coordinate Z(x,y) and the average plane within the area of ​​the region, and is calculated based on the following formula.

number

[0089] The conductivity described in this disclosure is determined by employing the electrochemical impedance spectroscopy (EIS) method, applying an alternating current of 1 Hz to 100 Hz and an amplitude of 50 mV to a polymer or electrolyte, measuring the resistance, and then calculating the conductivity using the following formula. Ci = (1 / R) × (L / A) However, Ci(S × cm) -1 ) is conductivity, R(Ω) is resistance, L(cm) is the pitch between the two electrodes, and A(cm 2 ) is the cross-sectional area of ​​the object being measured and the electrode. (L / A) is the conductivity coefficient (cm -1 It may be expressed as ).

[0090] The electrochemical stability described in this disclosure was determined using linear sweep voltammetry (LSV) at a scanning speed of 0.1 V / s, and Li / Li + By performing cyclic measurements under relative voltage conditions of -5V to 5V, it is possible to obtain the results of the corresponding changes in the relationship between current and potential.

[0091] The battery assemblies described in this disclosure may include a battery case, dome, weight piece, cover plate, tab, and cap.

[0092] The batteries described in this disclosure may be divided into primary batteries or secondary batteries, and the electrochemical carriers of the primary or secondary batteries may be at least one of button carriers, retractable carriers, or stacked carriers. They may be applied to portable electronic products such as digital cameras, mobile phones, laptops, and game console handles where lightweight and thin designs are required, and may also be applied to large-scale power storage industries such as lightweight electric vehicles and electric vehicles.

[0093] According to the above embodiment, specific examples are proposed below and described in detail in accordance with experimental data.

[0094] <Comparative Example>

[0095] A comparative example is a battery in which the negative electrode contains an active composition, and the active composition contains a silicon active material and a carbon active material. If the weight ratio of the silicon active material to the active composition is Ps and the weight ratio of the carbon active material to the active composition is Pc, Ps=10.0%, and Pc=90.0% This condition is met.

[0096] If the particle size of the silicon active material is sD50, sD50 = 80nm This condition is met.

[0097] When charging and discharging the comparative battery with a current of 2C, the maximum value between the discharge volumetric capacity at the 1st cycle and the discharge volumetric capacity at the 15th cycle is C2VMax, and when charging and discharging the comparative battery with a current of 2C, the discharge volumetric capacity at the 60th cycle is C2V60. C2VMax = 163.3mAh / cm 3 , and C2V60 = 0.5mAh / cm 3 This condition is met.

[0098] If we let C2V5 be the discharge volume capacity at the 5th cycle when charging and discharging the comparative battery with an electric charge of 2C, C2V10 be the discharge volume capacity at the 10th cycle when charging and discharging the comparative battery with an electric charge of 2C, and C2V20 be the discharge volume capacity at the 20th cycle when charging and discharging the comparative battery with an electric charge of 2C, C2V10 / C2V5 = 0.98, and C2V20 / C2V5 = 0.11 This condition is met.

[0099] If we define n85C2E15 as the total number of cycles that satisfy the Coulomb efficiency of the first 15 cycles when charging and discharging the comparative battery with a charge of 2C, and n85C2E50 as the total number of cycles that satisfy the Coulomb efficiency of the first 50 cycles when charging and discharging the comparative battery with a charge of 2C, then, n85C2E15=10 and n85C2E50=17 This condition is met.

[0100] If we assume that the average Coulomb efficiency for the first 15 cycles when charging and discharging the comparative battery with a charge of 2C is aC2E15, and the average Coulomb efficiency for the first 50 cycles when charging and discharging the comparative battery with a charge of 2C is aC2E50, then, aC2E15 = 85.4%, and aC2E50 = 109.1% This condition is met.

[0101] If we let C1V1 be the discharge volumetric capacity in the first cycle when charging and discharging the comparative battery with an electric charge of 1C, and C2V1 be the discharge volumetric capacity in the first cycle when charging and discharging the comparative battery with an electric charge of 2C, C2V1 / C1V1=0.61 It satisfies the following conditions.

[0102] When the comparative battery is charged and discharged with a charge of 2C, the maximum value between the discharge gravimetric capacity at the 1st cycle and the discharge gravimetric capacity at the 15th cycle is defined as C2GMax, and when the comparative battery is charged and discharged with a charge of 2C, the discharge gravimetric capacity at the 60th cycle is defined as C2G60. C2GMax = 335.2mAh / g, and C2G60 = 1.1mAh / g This condition is met.

[0103] When the comparative battery is charged and discharged with an electric charge of 2C, the discharge volumetric capacity at the 5th cycle is C2V5, and when the comparative battery is charged and discharged with an electric charge of 2C, the discharge volumetric capacity at the 60th cycle is C2V60. C2V60 / C2V5=0.01 This condition is met.

[0104] If we define n90C2E15 as the total number of cycles that satisfy the Coulomb efficiency of the first 15 cycles when charging and discharging the comparative battery with a charge of 2C, and n90C2E50 as the total number of cycles that satisfy the Coulomb efficiency of the first 50 cycles when charging and discharging the comparative battery with a charge of 2C, then, n90C2E15=1 and n90C2E50=8 This condition is met.

[0105] If we let C2V1 be the discharge volumetric capacity in the first cycle when charging and discharging the comparative battery with an electric charge of 2C, and C4V1 be the discharge volumetric capacity in the first cycle when charging and discharging the comparative battery with an electric charge of 4C, C4V1 / C2V1=0.97 This condition is met.

[0106] Detailed data for the comparative example batteries are shown in Tables 1 to 3 below.

[0107] <First Example>

[0108] The first embodiment is a battery in which the negative electrode contains an active composition, the active composition containing niobium titanium oxide, silicon active material, and carbon active material. The weight ratio of niobium titanium oxide to the active composition is Ptn, the weight ratio of silicon active material to the active composition is Ps, and the weight ratio of carbon active material to the active composition is Pc. Ptn=22.5%, Ps=10.0%, Pc=67.5%, Ptn / Ps=2.3, and Ptn / (Ps+Pc)=0.3 This condition is met.

[0109] If the particle size of the silicon active material is sD50 and the particle size of the niobium titanium oxide is tnD50, sD50 = 80 nm, tnD50 = 271 nm, and tnD50 / sD50 = 3.4 This condition is met.

[0110] Detailed data for the battery of the first embodiment are shown in Tables 1 to 3 below. The definitions of the other parameters in Tables 1 to 3 of the first embodiment are the same as those in the comparative example, and their explanation is omitted here.

[0111] <Second Example>

[0112] The second embodiment is a battery in which the negative electrode contains an active composition, the active composition containing niobium titanium oxide, silicon active material, and carbon active material. If the weight ratio of niobium titanium oxide to the active composition is Ptn, the weight ratio of silicon active material to the active composition is Ps, and the weight ratio of carbon active material to the active composition is Pc, Ptn=67.5%, Ps=10.0%, Pc=22.5%, Ptn / Ps=6.8, and Ptn / (Ps+Pc)=2.1 This condition is met.

[0113] If the particle size of the silicon active material is sD50 and the particle size of the niobium titanium oxide is tnD50, sD50 = 80 nm, tnD50 = 428 nm, and tnD50 / sD50 = 5.4 This condition is met.

[0114] Detailed data for the battery of the second embodiment are shown in Tables 1 to 3 below. The definitions of the other parameters in Tables 1 to 3 of the second embodiment are the same as those in the comparative example, and their explanation is omitted here. [Table 1] [Table 2-1] [Table 2-2] [Table 2-3] [Table 2-4] [Table 2-5] [Table 2-6] [Table 2-7] [Table 2-8] [Table 2-9] [Table 2-10] [Table 3-1] [Table 3-2] [Table 3-3]

[0115] <Third Example>

[0116] The third embodiment is a battery in which the negative electrode contains an active composition, the active composition containing niobium titanium oxide and silicon active material. If the weight ratio of niobium titanium oxide to the active composition is Ptn and the weight ratio of silicon active material to the active composition is Ps, Ptn=90.0%, Ps=10.0%, and Ptn / Ps=9.0 This condition is met.

[0117] If the particle size of the silicon active material is sD50 and the particle size of the niobium titanium oxide is tnD50, sD50 = 80 nm, tnD50 = 428 nm, and tnD50 / sD50 = 5.4 This condition is met.

[0118] Detailed data for the battery of the third embodiment are shown in Tables 4 to 6 below. The definitions of the other parameters in Tables 4 to 6 of the third embodiment are the same as those in the comparative example, and their explanation is omitted here.

[0119] <Fourth Example>

[0120] The fourth embodiment is a battery in which the negative electrode contains an active composition, the active composition containing niobium titanium oxide and silicon active material. If the weight ratio of niobium titanium oxide to the active composition is Ptn and the weight ratio of silicon active material to the active composition is Ps, Ptn = 92.5%, Ps = 7.5%, and Ptn / Ps = 12.3 This condition is met.

[0121] If the particle size of the silicon active material is sD50 and the particle size of the niobium titanium oxide is tnD50, sD50 = 80 nm, tnD50 = 428 nm, and tnD50 / sD50 = 5.4 This condition is met.

[0122] Detailed data for the battery of the fourth embodiment are shown in Tables 4 to 6 below. The definitions of the other parameters in Tables 4 to 6 of the fourth embodiment are the same as those in the comparative example, and their explanation is omitted here.

[0123] <Example 5>

[0124] The fifth embodiment is a battery in which the negative electrode contains an active composition, the active composition containing niobium titanium oxide and silicon active material. If the weight ratio of niobium titanium oxide to the active composition is Ptn and the weight ratio of silicon active material to the active composition is Ps, Ptn = 87.5%, Ps = 12.5%, and Ptn / Ps = 7.0 This condition is met.

[0125] If the particle size of the silicon active material is sD50 and the particle size of the niobium titanium oxide is tnD50, sD50 = 80 nm, tnD50 = 610 nm, and tnD50 / sD50 = 7.6 This condition is met.

[0126] Detailed data for the battery of the fifth embodiment are shown in Tables 4 to 6 below. The definitions of the other parameters in Tables 4 to 6 for the fifth embodiment are the same as those for the comparative example, and their explanation is omitted here. [Table 4] [Table 5-1] [Table 5-2] [Table 5-3] [Table 5-4] [Table 5-5] [Table 5-6] [Table 5-7] [Table 5-8] [Table 5-9] [Table 5-10] [Table 6-1] [Table 6-2] [Table 6-3]

[0127] While the embodiments described herein have been disclosed as described above, those skilled in the art can make various modifications and alterations, provided they do not deviate from the spirit and scope of the disclosure. Accordingly, the scope of protection provided for by the disclosure is limited to what is specified in the claims.

Claims

1. A composition comprising an active composition containing niobium titanium oxide and a silicon active material, The niobium titanium oxide comprises niobium, titanium, and oxygen. The aforementioned niobium titanium oxide is Ti ｘ Nb ｙ O ｚ or Ti （ｘ－ａ） M11 ａ Nb （ｙ－ｂ） M2 ｂ O （ｚ－ｃ） M3 ｃ M1, M2, and M3 are doped elements. z≦4x+5y, 0≦a<x, 0≦b<y, 0≦c<z The weight ratio of the niobium titanium oxide in the active composition is Ptn, If the weight ratio of the silicon active material to the active composition is Ps, 2.0 ≤ Ptn / Ps ≤ 12.3 A composition that satisfies the following conditions.

2. The composition according to claim 1, wherein the niobium titanium oxide is doped niobium titanium oxide.

3. The composition according to claim 2, wherein the doped niobium titanium oxide is doped with at least one element from Li, Mn, Ga, Ta, W, F, P, Na, or Mo.

4. The composition according to claim 1, wherein the weight ratio of the niobium titanium oxide in the active composition is greater than the weight ratio of the silicon active material in the active composition.

5. The weight ratio of the niobium titanium oxide in the active composition is Ptn. If the weight ratio of the silicon active material to the active composition is Ps, 2.3 ≤ Ptn / Ps ≤ 9.0 The composition according to claim 4 that satisfies the following conditions.

6. If the particle size of the silicon active material is sD50, 10 nm ≤ sD50 ≤ 10000 nm The composition according to claim 1 that satisfies the following conditions.

7. If the particle size of the niobium titanium oxide is tnD50, 20 nm ≤ tnD50 ≤ 9000 nm The composition according to claim 1 that satisfies the following conditions.

8. The particle size of the silicon active material is set to sD50. If the particle size of the niobium titanium oxide is tnD50, 0.01 ≤ tnD50 / sD50 ≤ 20.0 The composition according to claim 1 that satisfies the following conditions.

9. The composition according to claim 1, further comprising an inert composition selected from the group consisting of polymers, carbon materials, metals, alloys, nonmetallic oxides, metal oxides, and organic compounds.

10. The active composition further comprises a carbon active material, The weight ratio of the niobium titanium oxide in the active composition is Ptn. The weight ratio of the silicon active material to the active composition is Ps. If Pc is the weight ratio of the carbon active material to the active composition, 2.1≦Ptn / (Ps+Pc)≦9.0 The composition according to claim 1 that satisfies the following conditions.

11. A negative electrode comprising the composition described in claim 1.

12. Including the negative electrode described in claim 11, A battery in which the amount of electricity that takes one hour to completely discharge is defined as C.

13. If C2VMax is the maximum value between the discharge volume capacity at the 1st cycle and the discharge volume capacity at the 15th cycle when charging and discharging the battery with an electric charge of 2C, 140mAh / cm ３ ≦C2VMax≦275.1mAh / cm ３ The battery according to claim 12 that satisfies the following condition.

14. If the discharge volumetric capacity at the 60th cycle when charging and discharging the battery with an electric charge of 2C is C2V60, 200mAh / cm ３ ≦C2V60≦247.5mAh / cm ３ The battery according to claim 12 that satisfies the following condition.

15. When charging and discharging the battery with an electric charge of 2C, the discharge volumetric capacity in the 5th cycle is defined as C2V5. If the discharge volumetric capacity at the 10th cycle when charging and discharging the battery with an electric charge of 2C is C2V10, 0.70 ≤ C2V10 / C2V5 ≤ 1.03 The battery according to claim 12 that satisfies the following condition.

16. When charging and discharging the battery with an electric charge of 2C, the discharge volumetric capacity in the 5th cycle is defined as C2V5. If the discharge volumetric capacity at the 20th cycle when charging and discharging the battery with an electric charge of 2C is C2V20, 0.80 ≤ C2V20 / C2V5 ≤ 1.07 The battery according to claim 12 that satisfies the following condition.

17. If n85C2E15 is the total number of cycles that satisfy the condition that the Coulomb efficiency for the first 15 cycles of charging and discharging the battery with an electric charge of 2C is greater than 85% and less than 110%, then 10 ≤ n85C2E15 ≤ 15 The battery according to claim 12 that satisfies the following condition.

18. If n85C2E50 is the total number of cycles that satisfy the Coulomb efficiency for the first 50 cycles when charging and discharging the battery with an electric charge of 2C, then 40 ≤ n85C2E50 ≤ 50 The battery according to claim 12 that satisfies the following condition.

19. If the average value of the Coulomb efficiency for the first 15 cycles when charging and discharging the battery with an electric charge of 2C is aC2E15, 80% ≤ aC2E15 ≤ 110% The battery according to claim 12 that satisfies the following condition.

20. If the average value of the Coulomb efficiency for the first 50 cycles when charging and discharging the battery with an electric charge of 2C is aC2E50, then 75% ≤ aC2E50 ≤ 110% The battery according to claim 12 that satisfies the following condition.

21. When charging and discharging the battery with an electric charge of 1C, the discharge volumetric capacity in the first cycle is defined as C1V1. If the discharge volumetric capacity in the first cycle when charging and discharging the battery with an electric charge of 2C is C2V1, 0.85 ≤ C2V1 / C1V1 ≤ 1.14 The battery according to claim 12 that satisfies the following condition.

22. A composition comprising an active composition containing niobium titanium oxide and a silicon active material, The aforementioned niobium titanium oxide is doped niobium titanium oxide. The doped niobium titanium oxide contains niobium, titanium, and oxygen. The aforementioned doped niobium titanium oxide is Ti （ｘ－ａ） M11 ａ Nb （ｙ－ｂ） M2 ｂ O （ｚ－ｃ） M3 ｃ M1, M2, and M3 are doped elements. z≦4x+5y, 0≦a<x, 0≦b<y, 0≦c<z The weight ratio of the niobium titanium oxide in the active composition is Ptn, If the weight ratio of the silicon active material to the active composition is Ps, 2.3 ≤ Ptn / Ps ≤ 15.0 A composition that satisfies the following conditions.

23. The composition according to claim 22, wherein the doped niobium titanium oxide is doped with at least one element from Li, Mn, Ga, Ta, W, F, P, Na, or Mo.

24. moreover, 2.3 ≤ Ptn / Ps ≤ 12.3 The composition according to claim 22 that satisfies the following condition.

25. If the particle size of the silicon active material is sD50, 50 nm ≤ sD50 ≤ 3000 nm The composition according to claim 22 that satisfies the following condition.

26. The particle size of the silicon active material is set to sD50. If the particle size of the niobium titanium oxide is tnD50, 0.01 ≤ tnD50 / sD50 ≤ 20.0 The composition according to claim 22 that satisfies the following condition.

27. A negative electrode comprising the composition described in claim 22.

28. Including the negative electrode described in claim 27, A battery in which the amount of electricity that takes one hour to completely discharge is defined as C.

29. If C2GMax is the maximum value between the discharge gravimetric capacity at the 1st cycle and the discharge gravimetric capacity at the 15th cycle when charging and discharging the battery with an electric charge of 2C, 250mAh / g≦C2GMax≦564.7mAh / g The battery according to claim 28 that satisfies the following condition.

30. If the discharge gravimetric capacity at the 60th cycle when charging and discharging the battery with an electric charge of 2C is C2G60, 180mAh / g≦C2G60≦508.0mAh / g The battery according to claim 28 that satisfies the following condition.

31. When charging and discharging the battery with an electric charge of 2C, the discharge volumetric capacity in the 5th cycle is defined as C2V5. If the discharge volumetric capacity at the 60th cycle when charging and discharging the battery with an electric charge of 2C is C2V60, 0.90 ≤ C2V60 / C2V5 ≤ 0.99 The battery according to claim 28 that satisfies the following condition.

32. If n90C2E15 is the total number of cycles that satisfy the condition that the Coulomb efficiency for the first 15 cycles of charging and discharging the battery with an electric charge of 2C is greater than 90% and less than 110%, then 8 ≤ n90C2E15 ≤ 15 The battery according to claim 28 that satisfies the following condition.

33. If n90C2E50 is the total number of cycles that satisfy the condition that the Coulomb efficiency for the first 50 cycles of charging and discharging the battery with an electric charge of 2C is greater than 90% and less than 110%, then 30 ≤ n90C2E50 ≤ 50 The battery according to claim 28 that satisfies the following condition.

34. When charging and discharging the battery with an electric charge of 2C, the discharge volumetric capacity in the first cycle is defined as C2V1. If the discharge volumetric capacity in the first cycle when charging and discharging the battery with an electric charge of 4C is C4V1, 0.90 ≤ C4V1 / C2V1 ≤ 0.99 The battery according to claim 28 that satisfies the following condition.

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