627 results about "Lithium cobalt oxide" patented technology

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 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.

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 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 relates to the technical field of lithium ion batteries, in particular to a high-voltage lithium cobalt oxide positive electrode material and a preparation method thereof. According to the technical scheme, the chemical composition of the positive electrode material is at least two elements selected from Al, Mg, Ti and Zr. Through triple strategies of multi-element synergistic doping, core-shell structure design and surface defect regulation and control, breakthrough improvement of the performance of the high-voltage lithium cobalt oxide positive electrode material is achieved, and especially through the synergistic effect of a specific element combination Al + Mg + Ti and the coupling effect of the gradient-distributed F element and the nanometer defect structure, the performance of the high-voltage lithium cobalt oxide positive electrode material is improved. The structure phase change and the interface side reaction in the high-pressure circulation process are effectively inhibited, and the cycle life and the thermal stability of the material are remarkably improved.

The invention discloses a method for regenerating and preparing high-voltage lithium cobalt oxide by using an invalid lithium cobalt oxide material, and belongs to the technical field of battery recovery. The method comprises the following steps: S1, carrying out ball milling and mixing on failed lithium cobalt oxide powder and a sodium source, and then carrying out solid-phase sintering to obtain a P2 type sodium cobalt oxide and lithium cobalt oxide material; s2, the P2 type sodium cobaltate and lithium cobaltate material is placed in a lithium-containing solution for a hydrothermal reaction, a regenerated O2-O3 cotype lithium cobaltate material is obtained, the regenerated O2-O3 cotype lithium cobaltate material has the advantages of being good in cycling stability, high in rate capability, high in low-temperature performance and the like under the high voltage of 4.6 V, and the performance of the regenerated O2-O3 cotype lithium cobaltate material is superior to that of a commercial lithium cobaltate material.

The invention provides a modified lithium cobalt oxide positive electrode material and a preparation method thereof.The modified lithium cobalt oxide positive electrode material is of a core-shell structure and comprises a magnesium-aluminum-doped lithium cobalt oxide core material serving as the core-shell structure and a coating layer formed on the surface of the magnesium-aluminum-doped lithium cobalt oxide core material, and the coating layer is lithium titanium aluminum phosphate, lithium niobate and lithium phosphate; the chemical formula of the lithium titanium aluminum phosphate is Li < 1 + x > Al < x > Ti < 1 + 1-x > (PO4) 3, the chemical formula of the lithium niobate is Li3NbO4, the weight of the coating layer accounts for 0.2-2% of the weight of the modified lithium cobalt oxide positive electrode material, the weight ratio of the lithium titanium aluminum phosphate to the lithium niobate in the coating layer is 1: (0.4-2), and the chemical formula of the magnesium-aluminum doped lithium cobalt oxide core material is LiCo < 1-a-b-c > Mg Al Nb < c > O2. The modified lithium cobalt oxide positive electrode material provided by the invention has better battery performance at high temperature, high voltage and high rate.

The invention provides a method for strengthening recovery of a waste lithium iron phosphate material by using waste lithium cobalt oxide as an oxidizing agent. The method comprises the following steps: discharging and disassembling waste lithium iron phosphate and lithium cobalt oxide batteries to obtain positive plates; dissolving aluminum foil in the positive plate in a sodium hydroxide alkaline leaching solution to obtain lithium iron phosphate and lithium cobalt oxide positive electrode powder; the method comprises the following steps: leaching lithium iron phosphate positive electrode powder by adopting a deep-eutectic solvent, and meanwhile, realizing an enhanced leaching process by taking lithium cobalt oxide positive electrode powder as an oxidizing agent; and carrying out coordination separation and photo-reduction separation on the completely leached solution to realize selective recovery of cobalt, iron, phosphorus and lithium. According to the method, the oxidation-reduction capacity of the material is fully utilized to strengthen the leaching process, efficient recovery of valuable elements in the waste positive electrode material is achieved, and additional addition of an oxidizing agent and a reducing agent is avoided. The method can achieve the purposes of synergistic enhanced leaching and selective separation of the waste lithium cobalt oxide material and the waste lithium iron phosphate material, and is low in cost, high in recovery rate and wide in industrial application prospect.

The invention provides a coated modified lithium cobalt oxide material, a preparation method thereof, a positive electrode and a lithium ion battery. The preparation method comprises the following steps: providing a mixture, wherein the mixture sequentially comprises first lithium cobalt oxide particles, a coating agent and second lithium cobalt oxide particles from bottom to top; sequentially carrying out first mixing, second mixing and third mixing on the mixture; and sintering to obtain the coated modified lithium cobalt oxide material. The D50 particle size of the first lithium cobalt oxide particles is larger than that of the second lithium cobalt oxide particles; the mixing rotating speeds of the first mixing, the second mixing and the third mixing are sequentially increased. In the lithium cobalt oxide coating modification process, the positions of the first lithium cobalt oxide particles, the second lithium cobalt oxide particles and the coating agent in the mixture in the vertical direction are designed to form a sandwich structure, and a three-stage mixing process is combined, so that the mixing uniformity of the coating agent and the lithium cobalt oxide material is remarkably improved, and the coating performance of the lithium cobalt oxide material is improved. And uniform coating of the coating element on the surface of the lithium cobalt oxide material is realized.

The invention provides a positive plate, a battery, a battery pack and electric equipment. The positive plate comprises a positive current collector, a first positive active layer and a second positive active layer, wherein the first positive active layer and the second positive active layer are stacked on at least one side of the positive current collector; the first positive electrode active layer comprises a first positive electrode active material, and the second positive electrode active material comprises a first positive electrode active material and a second positive electrode active material; the first positive electrode active material comprises at least one of a manganese-based positive electrode active material, an iron-based positive electrode active material and a manganese-iron mixed-based positive electrode active material, and the second positive electrode active material comprises at least one of a ternary positive electrode active material, lithium cobalt oxide, lithium nickelate and lithium titanate; the second positive electrode active layer further comprises a second conductive agent, and the second conductive agent comprises at least two linear conductive agents and at least one of a sheet-shaped conductive agent and a point-shaped conductive agent. The positive plate has a special structure and composition, and can effectively improve the impedance increase of the battery and improve the cycle performance of the battery.

The invention relates to the technical field of batteries, in particular to a high-temperature-resistant lithium cobalt oxide positive electrode material and a preparation method and application thereof.The high-temperature-resistant lithium cobalt oxide positive electrode material comprises a lithium cobalt oxide matrix and a coating layer coating the surface of the lithium cobalt oxide matrix, the lithium cobalt oxide matrix is doped with Mg, Ti and La, and the coating layer is a fast ion coating layer of a Li-Gd-Ti-O4 spinel phase. Bulk phase doping is carried out through a high-temperature solid-phase method, Mg, Ti and La are doped in a lithium cobalt oxide matrix, and the lattice structure thermal stability of lithium cobalt oxide under high voltage (4.4 V) is improved; a fast ion coating layer of a Li-Gd-Ti-O4 spinel phase is formed on the surface of a lithium cobalt oxide matrix by adopting a solid phase method, and the comprehensive performance of the lithium cobalt oxide positive electrode material is improved through multiple mechanisms such as the lattice stabilization effect of rare earth ions, the interface barrier effect of composite oxide and lithium ion conductivity regulation and control; particularly, the capacity, the cycling stability, the thermal stability, the high-voltage tolerance and the like are realized.

The invention discloses a positive electrode material with a coating layer, a preparation method of the positive electrode material and a lithium ion battery. The positive electrode material with the coating layer comprises a positive electrode inner core and the coating layer coated on the surface of the positive electrode inner core, wherein the chemical composition of the positive electrode inner core is Li [alpha] Ni [x] Co [y] Al [z] A [m] O [2]; the coating layer contains an element Co and an element X, and the mass ratio of the element X in the coating layer to the element Co in the coating layer is 50%-100%; x is a metal element different from Co, and 50 wt.% or more of X is an Al element; the positive electrode core comprises a coating layer, the coating layer comprises a lithium cobalt oxide, the lithium cobalt oxide comprises specific contents of Li Co < 1-a > Co < 2 > O < 4 >, Li Co < 1-b > O and Li < Co > O < 2 >, and by taking the total mass of the positive electrode core as a reference, the content of Co element in the coating layer is 1000-4000 ppm. According to the invention, the positive electrode material can give consideration to both low heat production and gas production.

The invention discloses a composite positive electrode material, a preparation method thereof, a positive electrode plate and a solid-state lithium ion battery, and belongs to the technical field of secondary batteries. The composite positive electrode material comprises a lithium-rich positive electrode material, a halide solid electrolyte and high-voltage lithium cobalt oxide which are ball-milled and mixed. And the ratio of D90 of the lithium-rich positive electrode material to D90 of the high-voltage lithium cobalt oxide is 1: (1-5). The mass ratio of the lithium-rich positive electrode material to the high-voltage lithium cobalt oxide is (0.5-9.5): (9.5-0.5), and the halide solid electrolyte accounts for 5%-30% of the mass of the composite positive electrode material. When the composite positive electrode material is used for preparing the solid-state lithium ion battery, the discharge median voltage and the discharge specific capacity of the solid-state lithium ion battery can be improved.

To address the issue of the existing lithium-ion battery's excessive temperature rise during charging and discharging, the application provides a lithium-ion battery, including a positive electrode, a negative electrode, a non-aqueous electrolyte and a separator, and the separator is positioned between the positive electrode and the negative electrode; the positive electrode includes a positive electrode material layer containing a positive electrode active material, and the positive electrode active material includes a lithium cobalt oxide, and the non-aqueous electrolyte includes a non-aqueous organic solvent, a lithium salt and an additive, and the additive includes a compound represented by structural formula 1: the lithium-ion battery meets the following requirements: 0.1≤h / q*m≤15; and 10≤q≤50, 50≤h≤130, 0.01≤m≤3; the lithium-ion battery's maximum surface temperature (Tmax) and minimum surface temperature (Tmin) during 2C discharge to 100% DOD at 25°C meet the following requirements: (Tmax-Tmin) / Tmin* 100%≤30%.

The invention belongs to the technical field of lithium batteries, and particularly relates to a lithium cobalt oxide positive electrode material and a preparation method and application thereof. When the D50 particle size of the lithium cobalt oxide positive electrode material is 10-20 microns, the specific surface area of the lithium cobalt oxide positive electrode material is 0.4-0.8 m < 2 > / g; the real density of the lithium cobalt oxide positive electrode material is 4.85-5.03 g / cm < 3 >, and the tap density is 2.35-2.50 g / cm < 3 >; the lithium cobalt oxide positive electrode material has an R3-m space group structure, and the peak intensity ratio I (003) / I (104) of a 003 peak to a 104 peak in an XRD spectrogram of the lithium cobalt oxide positive electrode material is greater than or equal to 2.5. The method is characterized in that inert gas is introduced into a Li-Na hydrothermal replacement system to form aerosol, and Li-Na exchange is carried out under the protection of the aerosol, so that the D50 particle size, the specific surface area, the true density, the tap density and the I (003) / I (104) of XRD of the lithium cobalt oxide positive electrode material are in specific parameter ranges; the obtained lithium cobalt oxide positive electrode material has excellent lithium de-intercalation dynamic performance, so that a lithium ion battery is endowed with excellent capacity performance and rate capability.

In order to solve the problems of capacity attenuation and inadequate dynamic performance of the existing high-voltage LCO battery, the application provides a lithium-ion battery, including a positive electrode, a negative electrode and a non-aqueous electrolyte. The positive electrode includes a positive electrode current collector and a positive electrode material layer arranged on the positive electrode current collector, and the positive electrode material layer includes a positive electrode active material containing a lithium cobalt oxide, and the positive electrode has a resistivity less than or equal to 1000 Ω·cm; the non-aqueous electrolyte includes a non-aqueous organic solvent, a lithium salt and an additive, the additive includes a compound represented by structural formula 1: the lithium-ion battery meets the following requirements: 0.05≤m*d / f≤5, and 10≤d≤40, 3≤f≤30, 0.01≤m≤3. The lithium-ion battery provided by the present application effectively ensures the ionic conductivity and electronic conductivity of the positive electrode, as well as good dynamic and cycle performances without compromising energy density.

The invention relates to the technical field of lithium ion batteries, in particular to a positive electrode material and a preparation method thereof, a positive plate and a lithium ion battery. The positive electrode material comprises a lithium cobalt oxide matrix material and a nickel cobalt lithium manganate coating layer coating the surface of the lithium cobalt oxide matrix material; the crystalline phase of the lithium cobalt oxide matrix material is an O3 phase; the crystalline phase of the nickel cobalt lithium manganate coating layer is a composite phase of O2 and T2; the chemical formula of the nickel cobalt lithium manganate coating layer is LikNajNiaCobMncO2 + d, wherein k is more than or equal to 0.60 and less than or equal to 1.05, j is more than or equal to 0 and less than or equal to 0.02, a is more than or equal to 0.01 and less than or equal to 0.6, b is more than or equal to 0.02 and less than or equal to 0.97, c is more than or equal to 0.02 and less than or equal to 0.6, 1-a-b-c is more than or equal to 0 and less than or equal to 0.05, and d is more than or equal to-0.05 and less than The positive electrode material is high in capacity under high voltage and excellent in cycle performance.

The invention discloses a lithium ion battery based on molten salt electrolyte, which adopts a micron alloy material as a negative electrode material, and adopts LiFSI: KFSI mixed salt with the molar ratio of 9: 11 as LiFSI-KFSI molten salt electrolyte. The LiFSI-KFSI molten salt electrolyte and the micron-sized alloy negative electrode material have excellent compatibility, so that the micron-sized alloy negative electrode material shows excellent electrochemical performance in the LiFSI-KFSI molten salt electrolyte, including high initial coulombic efficiency, high capacity and long cycle life; according to the invention, one of high-Ni ternary, lithium cobalt oxide and lithium iron phosphate is selected as a positive electrode material to construct the lithium ion total battery based on the molten salt electrolyte, and the energy density of the lithium ion total battery is up to 400Wh / kg. The battery system has the advantages of high safety, excellent high-temperature characteristic, long calendar life and the like, and is a lithium ion battery with a very good application prospect.

The present application relates to the technical field of secondary batteries, and provides a secondary battery and an electronic device. A positive electrode in the secondary battery provided in the present application comprises lithium cobalt oxide having a lamellar rock salt type structure, the lithium cobalt oxide has a space group R-3m, and the lithium cobalt oxide comprises an Mg element, a Ni element and an Al element, and can synergize with a nitrile compound having a suitable content in an electrolyte, thereby improving the stability of the positive electrode material. The present application can improve the floating charge performance of the secondary battery and reduce the impedance, and thus the secondary battery has good safety and reliability.