841 results about "Lithium cobalt oxide" patented technology

The embodiment of the invention relates to a lithium cobalt oxide positive electrode material with a composite phase as well as a preparation method and application of the lithium cobalt oxide positive electrode material. The chemical general formula of the lithium cobalt oxide positive electrode material with the composite phase is AXCo (1-y) M (1y) O2, wherein x is more than or equal to 0.5 and less than or equal to 1, y is more than or equal to 0 and less than or equal to 0.03, A is Li or Li and Na, and M1 is one or more of A1, Zr, Ni, Mn, Y, Nb, La, Fe, Cu, Cr, Ti, W, Mg, Mo or Yb; the composite phase of the lithium cobalt oxide positive electrode material comprises an O2 phase, a T2 phase and an O3 phase; wherein the sum of the molar ratios of the O2 phase and the T2 phase in the composite phase is greater than or equal to 90%, and the molar ratio of the O3 phase is less than or equal to 10%. By regulating and controlling the composite phase proportion of the lithium cobalt oxide positive electrode material, the rate capability, the structural stability under high voltage, the stability of a thermodynamic structure, the specific capacity, a discharge platform and other characteristics of the positive electrode material can be effectively improved, so that the lithium cobalt oxide positive electrode material with high energy density and high stability is realized.

The invention relates to the technical field of lithium ion batteries, and provides a lithium cobalt oxide composite material which comprises a core body and a coating layer coating the core body, the core body comprises O2-phase lithium cobalt oxide, and the O2-phase lithium cobalt oxide is doped with an element M; the coating layer comprises an oxide containing an N element; the M element comprises at least one of Al, Mg, W, Ti, La, Zr, Ni, Mn and Y; n comprises at least one of Al, Mg, Y, W, Nb, La, Zr, Ti and P. The lithium cobalt oxide composite material provided by the invention is used as a positive electrode material of a lithium ion battery, and the cycling stability of the lithium ion battery under high potential is improved.

The invention provides a secondary battery and an electronic device comprising the same, the secondary battery comprises a positive pole piece, a negative pole piece, an isolating membrane and an electrolyte, and the electrolyte comprises a compound as shown in a formula I; based on the total mass of the electrolyte, the mass percentage content of the compound shown in the formula I is A%, and A is larger than or equal to 0.01 and smaller than or equal to 50; the positive pole piece comprises a positive active material, the positive active material comprises lithium cobalt oxide, the lithium cobalt oxide comprises an element M, and the element M comprises at least one of Al, Mg, Ti, Nb, Cr, Y, Sr or Zr; based on the total mass of the positive electrode active material, the mass percentage of the M element is B%, and 0.01 < = B < = 1. In the secondary battery, the electrolyte comprises the compound shown in the formula I, the positive electrode active material comprises the lithium cobalt oxide containing the M element, and the values of A and B are regulated and controlled in the range, so that the formation of a low-impedance CEI film is facilitated, and the secondary battery has good high-temperature storage stability and low-temperature discharge performance at the same time.

The invention provides a lithium cobalt oxide positive electrode material and a preparation method and application thereof, and the preparation method comprises the following steps: mixing a first lithium cobalt oxide burning product with a coating agent to obtain a first mixture; mixing the second lithium cobalt oxide primary burning product with a coating agent to obtain a second mixture; the particle size D50 of the second lithium cobalt oxide fired product is smaller than the particle size D50 of the first lithium cobalt oxide fired product; and mixing and sintering the first mixture and the second mixture to obtain the lithium cobalt oxide positive electrode material, according to the preparation method, distribution of coating substances in the lithium cobalt oxide material is balanced by adjusting a large and small particle grading mixing process, so that the content of coating agents on the surfaces of different particles is controllable, the problems that the stability of the material is poor and coating layers on the surfaces of the large and small particles are uncontrollable during blending are solved, and the capacity and the cycle performance of the material are improved.

The invention provides a positive electrode material, a lithium ion battery and a preparation method, and relates to the technical field of battery materials. The positive electrode material comprises an inner core and a coating layer, the inner core is a ternary material matrix, the coating layer is a fluorine-doped lithium cobalt oxide material, the lithium cobalt oxide material contains Co < 2 + > and Co < 3 + >, and in the coating layer, the fluorine element and the Co < 2 + > are both distributed progressively from the surface to the center. The positive electrode material effectively improves the capacity fading problem under high voltage, and shows excellent circulation capability, high capacity and low impedance under high voltage.

The invention relates to the technical field of battery materials, and discloses a lithium cobalt oxide composite positive electrode material with a coating layer, a preparation method thereof, a positive electrode and a battery. The lithium cobalt oxide composite positive electrode material with the coating layer comprises a main body and the coating layer coated outside the main body, the chemical formula of the main body is LixNayCo1-zMzO2, x is more than or equal to 0.7 and less than or equal to 0.74, y is more than 0 and less than or equal to 0.1, z is more than or equal to 0 and less than or equal to 0.1, and M is selected from at least one of Al, Mg, W, Ti, La, Zr, Y, Ni, Mn and Nb; the coating layer is a metal oxide; and a crystal phase in the main body is a T2 and O2 composite phase. The preparation method comprises the following steps: firstly preparing a P2-phase sodium cobalt oxide precursor, coating the precursor, and then carrying out ion exchange with a lithium source mixed molten salt to finally obtain the composite positive electrode material of T2 and O2 composite phase lithium cobalt oxide with a coating layer. The positive electrode material has good electrochemical performance.

The invention belongs to the technical field of lithium ion battery materials, and particularly relates to cobalt carbonate and a preparation method thereof, cobaltosic oxide and a lithium ion battery. The crystal grain size of the cobalt carbonate (104) crystal face is 200-250, and the median particle size Dv50 is 16-20 [mu] m. The preparation method of the cobalt carbonate comprises the following steps: adding a precipitant solution and a cobalt salt solution into a reaction kettle in a parallel flow manner, carrying out a co-precipitation reaction, controlling the reaction pH value, starting a thickener when the volume of a material in the reaction kettle reaches a target value, continuing the reaction until large-particle cobalt carbonate slurry is obtained, and carrying out solid-liquid separation and washing to obtain the cobalt carbonate. Cobalt carbonate is subjected to first sintering, mixed with a doping agent and then subjected to second sintering, and cobaltosic oxide with the (311) crystal face grain size being 660-700 and the median particle size Dv50 being 14-18 microns is prepared. The cobaltosic oxide is high in mechanical strength and good in reaction activity with a lithium source, and the prepared lithium cobalt oxide positive electrode material is relatively excellent in electrochemical performance.

The invention discloses a method for recycling a lithium cobalt oxide positive electrode material in a waste lithium battery through a cascade pyrolysis method, and relates to the technical field of battery positive electrode recycling. The waste lithium battery is subjected to real-time adjustment according to a first-stage temperature adjustment formula within a first-stage pyrolysis temperature range to obtain a first-stage product; calculating a second-stage formula temperature of the first-stage product in a second-stage pyrolysis temperature range according to a second-stage temperature formula, constructing a second-stage temperature control model, and predicting a second-stage real-time prediction temperature; a second-stage product is obtained according to the second-stage formula temperature and the second-stage real-time predicted temperature, a third-stage formula temperature of the second-stage product is calculated according to a third-stage temperature formula in a third-stage pyrolysis temperature range, a third-stage temperature control model is constructed, a third-stage real-time predicted temperature is predicted, and a lithium cobalt oxide product is obtained according to the third-stage formula temperature and the third-stage real-time predicted temperature. The purity and the electrochemical performance of the lithium cobalt oxide positive electrode material are improved, and meanwhile, the energy consumption is reduced.

The invention discloses cobaltosic oxide, a preparation method thereof, lithium cobalt oxide, a positive pole piece and a battery, and relates to the technical field of lithium battery positive pole materials. The Dv50 of the cobaltosic oxide, the grain size D (111) of the (111) crystal face and the specific surface area BET meet the following relation: 3.33 [mu] m < 3 > / g < = # imgabs0 # < = 6.90 [mu] m < 3 > / g, wherein the Dv50 of the cobaltosic oxide is 3-20 [mu] m. The cobaltosic oxide is obtained by pre-sintering and calcining cobalt carbonate with the crystallinity of 30%-80% and the median particle size Dv50 of 3-22 [mu] m; the reaction activity of the cobaltosic oxide and a lithium source is high, the mechanical property is good, the lithium ion diffusion rate of the obtained lithium cobalt oxide is high, and the specific capacity and the first charge-discharge efficiency are relatively high.

The invention relates to the technical field of battery materials, and discloses an O2-phase lithium cobalt oxide positive electrode material, a preparation method thereof, a positive electrode and a battery. The chemical formula of the O2-phase lithium cobalt oxide positive electrode material is LiaNabCocMdAeO2-fXf, M and / or A are selected from any one or more of Mg, Al, W, Ti, La, Zr, Y, Ni, Mn, K and Te, a is larger than or equal to 0.9 and smaller than or equal to 1, b is larger than or equal to 0 and smaller than or equal to 0.01, c is larger than or equal to 0.95 and smaller than or equal to 1, d is larger than or equal to 0 and smaller than or equal to 0.05, e is larger than or equal to 0 and smaller than or equal to 0.01, and f is larger than or equal to 0 and smaller than or equal to 0.01. Under the synergistic effect of the doped and coated elements (M and A elements), the positive electrode material not only can reduce the existence of polycrystals and twin crystals, improve the interlayer spacing, reduce the content of residual Na and stabilize the bulk phase structure, but also can improve the stability of an interface and inhibit the generation of side reactions of the interface.

The invention discloses a lithium cobalt oxide positive electrode material as well as a preparation method and application thereof, and relates to the technical field of lithium ion batteries. According to the lithium cobalt oxide positive electrode material provided by the invention, the O2-phase lithium cobalt oxide main body material is coated with the coating layer containing the boron compound, and the provided O2-phase lithium cobalt oxide positive electrode material after surface optimization has higher initial efficiency, capacity and cycle stability than conventional O3-phase lithium cobalt oxide. The coating method adopted by the invention can be realized only by low-temperature secondary sintering, the O2 phase structure of the bulk phase is maintained, the boron-containing compound selected for coating generates a stable interface on the surface, and on the premise of not influencing lithium ion diffusion, the side reaction of the interface is inhibited, the structure is stabilized, and the cycling stability of the material is improved.

The invention relates to a spherical lithium cobalt oxide positive electrode material with an O2 phase structure and a preparation method and application thereof, the chemical general formula of the spherical lithium cobalt oxide positive electrode material is LiaXbMpAlqCo (1-p-q) O2, 0.5 < a < = 1, 0 < = b < 0.2, 0 < = p < = 0.5, 0 < = q < = 0.5, an X element is selected from at least one of Na and K, and an M element is selected from at least one of Ni, Mn, Mg, Cu, Ca, Zn, Zr, B, Nb, Fe, Cr, Y, La, Ce, Cd, Mo, F or Ti; xRD (X-Ray Diffraction) characteristic peaks exist at the same time when 2 theta A1 is equal to 18.3 to 18.9 degrees, 2 theta A2 is equal to 37.9 to 38.4 degrees and 2 theta A3 is equal to 46.7 to 47.3 degrees, and the full width at half maximum of the (002) characteristic peak is 0.355 to 0.495; the spherical lithium cobalt oxide positive electrode material has higher specific capacity and higher cycling stability.

The invention belongs to the technical field of lithium ion batteries, and particularly relates to an antimony modified lithium cobalt oxide material as well as a preparation method and application thereof. The antimony modified lithium cobalt oxide material provided by the invention comprises layered lithium cobalt oxide and an antimony layer wrapping the surface of the layered lithium cobalt oxide, the antimony layer includes an antimony oxide compound. The lithium cobalt oxide is wrapped by the antimony layer, so that the interface stability of the lithium cobalt oxide is enhanced, the lithium cobalt oxide has good structural stability under high voltage, and the lithium cobalt oxide has excellent cycling stability and rate capability as a positive electrode material.

The invention relates to a lithium cobalt oxide composite material and a preparation method thereof, an electrode plate and a battery. The lithium cobalt oxide composite material comprises a lithium cobalt oxide core and a shell coating at least part of the surface of the lithium cobalt oxide core, and the lithium cobalt oxide core comprises first lithium cobalt oxide and second lithium cobalt oxide; the median particle size of the first lithium cobalt oxide is d1, the median particle size of the second lithium cobalt oxide is d2, the median particle size of a precursor first cobalt source of the first lithium cobalt oxide is d3, and d3 is larger than or equal to 3 microns and smaller than or equal to 5 microns; the median particle size of a second cobalt source of a precursor of second lithium cobalt oxide is d4, and d4 is more than or equal to 3 microns and less than or equal to 5 microns; wherein d1-d3 is more than or equal to 10 microns and less than or equal to 17 microns; 0 [mu] m < = d2-d4 < = 3 [mu] m. According to the preparation method, the compaction density of the lithium cobalt oxide composite material can be effectively improved, so that the specific capacity and the cycle performance of the lithium ion battery are improved.

The invention belongs to the field of batteries, and particularly discloses a lithium cobalt oxide positive electrode material and a preparation method and application thereof, the positive electrode material comprises a doped lithium cobalt oxide matrix, an inner coating layer and an outer coating layer; an inner coating layer is arranged on the surface of the doped lithium cobalt oxide substrate, and an outer coating layer is arranged on the surface of the inner coating layer; the doped lithium cobalt oxide matrix is LiCo < x > M < y > O < 2 >, and the inner coating layer contains LiF and AlF < 3 >; and Li3PO4 is contained in the outer coating layer. According to the invention, the lithium cobalt oxide matrix is doped by adopting the doping element, and meanwhile, the specific inner coating layer and the specific outer coating layer are arranged on the surface of the doped lithium cobalt oxide matrix, so that structural collapse and capacity attenuation of the positive electrode material in the charge-discharge process under high voltage can be avoided; and thus, the positive electrode material can have relatively high specific capacity and excellent cycling stability under high voltage.

The invention provides a near-pure-phase O2 type lithium cobalt oxide positive electrode material and a preparation method and application thereof.According to the method, a P2 type near-pure-phase NCO precursor material with the high Na / Co specific content is adopted for successfully synthesizing a near-pure-phase O2 type LCO material through Li-Na ion replacement, the Li / Co atomic ratio ranges from 0.9 to 1.2, the content of free Li2CO3 of the material is smaller than or equal to 0.5 wt.%, the content of Li < + > occupied by the structure is high, and the material can be applied to the field of lithium ion battery cathode materials. And an X-ray diffraction pattern has no miscellaneous peaks except the O2-type structure. Therefore, by selecting reasonable doping modification and primary sintering conditions, a near-pure-phase P2 type NCO precursor material with a high Na / Co ratio synthesized in an air atmosphere is provided, and a high-proportion structure of the P2 type precursor material occupies Na, good Na < + > diffusion dynamics performance and a stable structure are utilized, so that the high-purity NCO precursor material is obtained. And the near-pure-phase O2 type lithium cobalt oxide positive electrode material with high Li / Co ratio, low free Li2CO3 content, low Na < + > residue and stable structure is synthesized through Li-Na ion replacement.

The invention discloses a positive electrode lithium supplementing agent, a positive electrode plate, a secondary battery and a power utilization device, and belongs to the technical field of batteries, the positive electrode lithium supplementing agent comprises lithium phytate and a lithium supplementing agent, and the lithium supplementing agent comprises at least one of Li5FeO4, Li6CoO4 and Li2NiO2. The lithium phytate and the lithium supplementing agent are combined to serve as the positive electrode lithium supplementing agent, the lithium phytate and the lithium supplementing agent act together, active oxygen and metal ions released by the lithium supplementing agent are adsorbed, side reactions of the electrolyte are reduced, the electrochemical stability of a system is maintained under high voltage, meanwhile, lithium can be completely released under a high-voltage lithium cobalt oxide system, and the service life of the lithium battery is prolonged. The release amount of a lithium source is effectively increased, the lithium consumption of a negative electrode SEI film forming reaction is fully supplemented, the embedding and separating process of lithium ions in a positive electrode material is promoted, the gas expansion of the secondary battery is improved, and the cycle life of the secondary battery is effectively prolonged.

In order to solve the problems that an existing positive electrode material is unstable in structure and low in energy density, the invention provides a positive electrode material and a preparation method thereof, a positive electrode plate and a battery, the positive electrode material comprises lithium cobalt oxide of a layered structure, the chemical formula of the lithium cobalt oxide is Li < 1-alpha-beta > Na < alpha > (Mg < gamma > Ti < delta > Co < 1-gamma-delta >) O2, alpha is smaller than or equal to 0.005, and beta is 0.02-0.05; gamma is equal to 0.002 to 0.004, delta is equal to 0.001 to 0.003, and gamma + delta is equal to 0.003 to 0.006.

A lithium-ion secondary battery having excellent discharge characteristics even in a low-temperature environment is provided. The lithium-ion secondary battery includes a positive electrode, a negative electrode, and an electrolyte solution. The positive electrode includes lithium cobalt oxide with a median diameter (D50) of greater than or equal to 1 μm and less than or equal to 12 μm. The lithium cobalt oxide contains magnesium in its surface portion. The negative electrode includes a graphite particle, a silicon particle, and a polymer including a carboxy group. The electrolyte solution contains a mixed solvent of a fluorinated cyclic carbonate and a fluorinated chain carbonate.

The present invention provides a battery, comprising: a positive plate comprising a positive current collector and a positive active layer present on at least one side surface of the positive current collector, the positive active layer comprising a positive active material, the positive active material comprising lithium cobalt oxide; the negative electrode plate comprises a negative electrode current collector and a negative electrode active layer existing on the surface of at least one side of the negative electrode current collector, and a concave part is formed in the surface of the negative electrode active layer; the battery meets the condition that k / h is more than or equal to 0.03% and less than or equal to 0.6%; # imgabs0 # 0.8 [mu] m < = D1 < = 3 [mu] m; wherein k is the elongation rate of the positive plate; h is the depth of the recess in [mu] m; d1 is the particle size Dn90 of the lithium cobalt oxide, and the unit is micron; d2 is the particle size Dn50 of the lithium cobalt oxide, and the unit is micron; s is the tensile strength of the positive plate. The preparation method can inhibit the breakage of the pole piece, and improves the high-temperature cycle life, safety and other performances of the battery.

This invention relates to a method for preparing a p-aminobenzenesulfonic acid blended nanofiltration membrane and its application. The invention aims to address the technical problem that existing polymer thin films struggle to simultaneously increase permeate flux while improving retention rate. This invention provides a nanofiltration membrane with high efficiency in separating cobalt and lithium ions and significantly enhanced permeate flux. It achieves this by doping p-aminobenzenesulfonic acid during the preparation of traditional TFC nanofiltration membranes, efficiently introducing sulfonic acid groups to promote the formation of an ordered nanochannel structure in the polyamide network, thereby increasing water flux. Simultaneously, the negative charge carried by the sulfonic acid groups enhances the overall electronegativity of the membrane, making it more effective against Co ions. 2+ The electrostatic adsorption capacity is significantly higher than that of Li + This enables efficient separation of cobalt and lithium ions. The nanofiltration membrane material provided by this invention can be widely used in the resource-based treatment of acid leaching wastewater from lithium cobalt oxide batteries, achieving efficient separation and recovery of cobalt and lithium, and improving economic benefits and resource utilization.

The invention relates to the technical field of batteries, in particular to a composite positive electrode material, a preparation method thereof and a battery. The composite positive electrode material comprises a positive electrode substrate, a fast ion conductor layer and a halide layer, the positive electrode substrate comprises a doped lithium cobalt oxide material; the fast ion conductor layer is positioned on the surface of the positive electrode substrate and comprises an oxide of a metal element Q with a spinel phase; the halide layer is located on the surface of the fast ion conductor layer and comprises element lithium, metal element M and halogen X. Through coordination and cooperation of the matrix material, the fast ion conductor layer and the halide layer, the structural stability and the surface morphology of the material can be effectively improved, the defects of the material are overcome, and the composite positive electrode material has excellent conductivity and has excellent cycling stability and rate capability at high temperature and / or high voltage, so that the battery has high safety performance.

The invention belongs to the technical field of lithium cobalt oxide positive electrodes, and discloses a high-entropy doped lithium cobalt oxide positive electrode material as well as a preparation method and application thereof. The molecular formula of the high-entropy doped lithium cobalt oxide positive electrode material is LiCo (1-y) MgxAlyPrzTi (0.0025) O2 or LiCo (1-y) MgxAlyNdzTi (0.0025) O2, x is greater than or equal to 0.001 and less than or equal to 0.01, y is greater than or equal to 0.001 and less than or equal to 0.01, and z is greater than or equal to 0.001 and less than or equal to 0.01. The high-entropy doped lithium cobalt oxide positive electrode material disclosed by the invention is formed by combining a surface integration layer and bulk phase doping, so that irreversible transformation of a material structure from an O3 phase to an O1-O3 blended phase (H1-3) is inhibited, and slippage of a transition metal layer and collapse and irreversible phase transformation of an O3 lattice structure are prevented; the stability of a surface interface and a bulk phase structure of the lithium cobalt oxide positive electrode material under high voltage is improved, and the lithium cobalt oxide positive electrode material can be applied to a lithium ion battery.

The invention discloses a preparation method of a lithium cobalt oxide material, the lithium cobalt oxide material and a secondary battery, and belongs to the field of positive electrode materials. The lithium cobalt oxide material which is stable in surface structure and good in cycle performance is prepared through acid leaching, phosphate primary coating and fluorine acid ammonium salt secondary coating of lithium cobalt oxide in sequence. The lithium cobalt oxide reacts with H < + > in the acid solution in the acid leaching process, and active sites are formed on the surface of the lithium cobalt oxide; pO4 < 3-> in the phosphate reacts with active sites in the subsequent primary coating process to form stably combined primary coated lithium cobalt oxide, and the phosphate is distributed on the surface of the lithium cobalt oxide in a dotted manner, so that the corrosion of an electrolyte can be inhibited; in the secondary coating process, NH4 < + > in the ammonium fluoride salt is combined with surface O < 2-> of an uncoated area on the surface of the primary coated lithium cobalt oxide to generate water and ammonia gas, so that a tightly coated fluoride coating layer is formed, and the fluoride coating layer can effectively reduce corrosion of hydrofluoric acid generated by electrolyte decomposition to the positive electrode material, reduce release of oxygen on the surface layer and improve the service life of the positive electrode material. The surface structure of the lithium cobalt oxide material is further stabilized.

The invention belongs to the field of preparation of a lithium ion battery positive electrode material, and particularly relates to an organic metal framework coated lithium cobalt oxide positive electrode material as well as a preparation method and application thereof. According to the scheme, a lithium cobalt oxide material, methanol, dimethyl imidazole cobalt, titanium carbide and sodium dihydrogen phosphate monohydrate are mixed according to the mass ratio of 1: (0.070-0.080): (0.001-0.002): (0.001-0.003): (0.001-0.002) and sintered, and the lithium cobalt oxide positive electrode material coated with the organic metal frame is obtained. According to the scheme, by utilizing the synergistic effect of a metal organic framework coating layer formed by pyrolysis of dimethyl imidazole cobalt, a three-dimensional conductive network constructed by titanium carbide and a phosphate interface layer, the mechanical strength of the coating layer is synergistically improved, lithium ion diffusion is accelerated, the internal resistance of the battery is reduced, the side reaction of an electrode / electrolyte is reduced, and the volume expansion of lithium cobalt oxide and cobalt dissolution are inhibited; and the high-temperature cycling stability and the rate capability of the lithium cobalt oxide battery are obviously improved. Meanwhile, the invention also provides an application of the organic metal framework coated lithium cobalt oxide positive electrode material in a battery.

The invention discloses an O2-phase lithium cobalt oxide positive electrode material and a preparation method thereof, and belongs to the field of lithium ion battery electrode materials. The preparation method comprises the following steps: uniformly mixing a cobalt precursor containing modified metal M with sodium carbonate by a dry method, pre-sintering after uniformly mixing, and sintering at high temperature to obtain P2-phase NaxCoO2; and carrying out solid-phase ion exchange or liquid-phase ion exchange with a lithium salt, washing, filtering and drying to obtain the O2-phase lithium cobalt oxide positive electrode material. The O2-phase lithium cobalt oxide positive electrode material prepared by the invention has good structural reversibility under high voltage, and the capacity, cycle and other performance of the lithium ion battery positive electrode material under high voltage can be remarkably improved.

In order to solve the problem that an existing battery with high-voltage lithium cobalt oxide matched with a silicon-doped negative electrode is insufficient in cycle performance and safety performance, the invention provides a lithium ion battery which comprises a positive electrode, a negative electrode, a diaphragm and a non-aqueous electrolyte, and the non-aqueous electrolyte comprises a non-aqueous organic solvent, electrolyte salt and an additive, the non-aqueous organic solvent comprises acetic acid 2, 2-difluoroethyl ester, the additives comprise a first additive and a second additive, the first additive comprises a sulfur-containing additive as shown in a structural formula 1: # imgabs0 # structural formula 1, and the second additive comprises a nitrile compound; the lithium ion battery satisfies the following conditions: # imgabs 1 #, 0.1 < = a < = 3, 0.5 < = b < = 5, 1 < = c < = 40, 0.2 < = d < = 7, and 5 < = e < = 30. The lithium ion battery provided by the invention has relatively excellent high-temperature cycling stability and relatively good thermal shock resistance safety performance.

The invention discloses a high-exposure-ratio {010} active surface O2 type cobalt-based layered oxide and a preparation method and application thereof, and belongs to the technical field of lithium ion battery positive electrode material preparation. Comprising the following steps: preparing a cobalt-based hydroxide precursor with a large {010} crystal face area through a coprecipitation method, introducing a sodium source, preparing a sodium-embedded cobalt-based layered oxide through a high-temperature calcination method, and carrying out a low-temperature ultrasonic liquid-phase ion exchange reaction on the sodium-embedded cobalt-based layered oxide and a lithium salt solution to prepare the {010} active face O2 type cobalt-based layered oxide with a high exposure ratio. According to the invention, by increasing the exposure ratio of the {010} active surface, the structural stability and lithium ion diffusion kinetics of the layered cobalt-based oxide positive electrode material are enhanced, so that the purposes of improving the energy density, rate capability and cycle performance of high-voltage O2 layered lithium cobalt oxide are achieved.

The invention belongs to the technical field of waste lithium battery recovery, and particularly relates to a method for selectively extracting lithium from a waste lithium battery positive electrode material based on activation and oxidation, which comprises the following steps: mixing the waste lithium battery positive electrode material, an oxidizing agent, an activating agent and a solvent, stirring and leaching, and carrying out solid-liquid separation to obtain a lithium-rich leaching solution and valuable metal leaching residues; wherein the activating agent is one or more than two of divalent ferrite, divalent cobalt salt, divalent manganese salt, divalent copper salt and monovalent silver salt, and the waste lithium battery positive electrode material is selected from one or more than two of waste nickel cobalt lithium manganate batteries, waste nickel cobalt lithium aluminate batteries, waste lithium cobalt oxide batteries and waste lithium manganate batteries. Through the synergistic effect of the oxidizing agent and the activating agent, preferential extraction of lithium in the raw material is achieved in one step, the problem that the lithium loss amount is large in the later lithium extraction process is solved, and the method has the advantages of being easy and convenient to operate, short in technological process, good in lithium selectivity, high in lithium leaching rate, wide in temperature application range and low in recovery cost.

The invention provides a high-entropy oxide-coated lithium cobalt oxide positive electrode material and a preparation method thereof, the high-entropy oxide-coated lithium cobalt oxide positive electrode material comprises lithium cobalt oxide located in the material and a coating layer coating the surface of the lithium cobalt oxide, the chemical formula of the lithium cobalt oxide located in the core is LiCoaTm1-aO2, a is greater than or equal to 0.99 and less than or equal to 0.999, Tm is at least one of Mg, Al, Ti, Sr, Zr, Mo and Nb, and the coating layer is coated on the surface of the lithium cobalt oxide. The coating layer is a high-entropy oxide coating layer, the chemical formula of the high-entropy oxide is MOx, and M comprises at least six of Fe, Co, Ni, Mn, Al, Cr, Zn and Si, 1 lt; xlt; and 2, the total valence is zero. The high-entropy oxide coated lithium cobalt oxide positive electrode material has the advantage that the rate capability, the capacity and the cycle performance of the material are improved.