348 results about "Manganate" patented technology

The application relates to the technical field of material preparation, and discloses multi-element carbon-coated lithium manganate, a preparation method thereof and a secondary battery. The multi-element carbon-coated lithium manganate comprises a lithium manganate core and a carbon nanotube layer and a hard carbon layer which are sequentially coated on the lithium manganate core. The chemical formula of the lithium manganate core is LiAl a X b Mn 2‑a‑b O4, wherein 0.01<=a<=0.10, 0.01<=b<=0.05, and X comprises at least one of Co, Cr, Ti, V and B. The preparation method of the multi-element carbon-coated lithium manganate comprises the following steps: (I) preparing doped lithium manganate, (II) preparing carbon nanotubes and (III) multi-element carbon coating. The multi-element carbon-coated lithium manganate has high conductivity, rate performance, cycle performance and safety performance, and can be used as an alternative positive electrode material with high cycle and excellent fast-charging performance.

The invention provides an in-situ synthesis method and application of aluminum-doped battery grade manganous-manganic oxide and lithium manganate. An aluminum-doped manganous-manganic oxide precursor is synthesized in one step through a direct homogeneous oxidation method, and then the lithium manganate positive electrode material is prepared through a high-temperature solid-phase reaction. The technological parameters such as the volume of a base solution, the concentration of a manganese-containing solution, the concentration of ammonia water, the flow of a salt solution, the stirring speed and the reaction temperature are regulated and controlled, and the synthesized manganous-manganic oxide precursor is uniform in particle size and has relatively high tap density and relatively low specific surface area. The capacity retention ratio of the obtained aluminum-doped lithium manganate reaches 85.16% after the aluminum-doped lithium manganate is circulated for 100 circles at the rate of 0.2 C, and the discharge specific capacity of the aluminum-doped lithium manganate is 105.8 mAh / g at the high rate of 5C. According to the method, the efficient recycling of waste battery resources is realized, the production cost is reduced, and meanwhile, the problem of non-uniformity of a conventional doping process is solved.

The present invention relates to the field of battery materials, and provides a lithium manganate cathode material coated with lithium triborate and a preparation method thereof. The cathode material is a porous lithium manganate / lithium triborate composite electrode material, which includes porous lithium manganate with a highly connected directional columnar pore structure and a lithium triborate coating covering the pore surface, with a mass ratio of (86.0~92.0):(8.0~14.0), a coating thickness of 600~800 nm, a pore diameter of 45~95 μm, and a porosity of 65~78%. The preparation method includes: preparing a precursor colloidal solution by the sol-gel method, obtaining porous lithium manganate through low-temperature freezing molding and freeze-drying, and forming a cathode substrate through pre-oxidation and high-temperature sintering; subsequently, using vacuum-assisted impregnation, ultrasound, and nitrogen pressure to promote the penetration of the lithium triborate precursor solution, and forming a uniform coating layer through gradient drying and annealing treatment. The present invention significantly improves the crystal structure stability of the cathode material, inhibits manganese dissolution, improves the cycle life and rate performance, and has wide application value.

The invention discloses an electrolyte for a lithium manganate lithium ion battery and a preparation method thereof, and the electrolyte comprises the following components in percentage by mass: 70-90% of an organic solvent, 5-20% of a lithium salt and 0.5-10% of an additive, the organic solvent is formed by mixing cyclic carbonate and chain carbonate according to the mass ratio of (10-30): (70-90); the lithium salt adopts one or more of lithium hexafluorophosphate (LiPF), lithium tetrafluoroborate (LiBF) and lithium bis (trifluoromethane sulfonimide) (LiTFSI), and the concentration of the lithium salt is 0.8 to 1.5 mol / L; the additives comprise a manganese ion complexing agent, a film forming accelerant and an antioxidant. In the invention, the manganese ion inhibition effect is as follows: the complexing agent and Mn (II) ions form a stable complex, so that the concentration of free Mn (II) in the electrolyte is reduced by more than 80%, migration and deposition of the free Mn (II) to the negative electrode are inhibited, and the dissolution amount of the Mn element of the positive electrode is reduced by 65% after 500 times of circulation at 45 DEG C.

The invention provides an electrochemical device and an electronic device comprising the same, the electrochemical device comprises a positive pole piece, the positive pole piece comprises a current collector and a positive pole material layer located on at least one surface of the current collector in the thickness direction, the positive pole material layer comprises a first positive pole material layer and a second positive pole material layer, the second positive electrode material layer is located between the first positive electrode material layer and the current collector, the positive electrode material layer comprises a positive electrode active material, the positive electrode active material comprises two or more than two nickel cobalt lithium manganate ternary materials, the two or more than two nickel cobalt lithium manganate ternary materials are divided into two groups, the chemical formula of the first group of lithium nickel cobalt manganate ternary materials is Lin1Nix1Coy1Mnz1M1m1O2, x1 + y1 + z1 + m1 is equal to 1 and smaller than or equal to 0.60, the chemical formula of the second group of lithium nickel cobalt manganate ternary materials is Lin2Nix2Coy2Mnz2M2m2O2, x2 + y2 + z2 + m2 is equal to 1 and larger than 0 and smaller than or equal to 0.14, and the two groups of lithium nickel cobalt manganate ternary materials are located in the first positive electrode material layer and the second positive electrode material layer respectively.

The invention provides a secondary battery and an electronic device, the secondary battery comprises a positive pole piece and a negative pole piece, the positive pole piece comprises a positive pole material layer, the positive pole material layer comprises a positive pole active material, and the positive pole active material comprises a manganese-containing material; the manganese-containing material comprises at least one of lithium manganate, lithium iron manganese phosphate, a lithium-rich manganese-based material or nickel cobalt lithium manganate. The negative pole piece comprises a first additive, the first additive comprises at least one of carboxylate, sulfonate or a metal organic framework compound, carboxylate comprises at least one of lithium oxalate, sodium citrate, sodium maleate or sodium tartrate, sulfonate comprises at least one of sodium benzenesulfonate, sodium dodecyl benzene sulfonate or sodium methanesulfonate, and metal organic framework compound comprises at least one of lithium oxalate, sodium citrate, sodium maleate or sodium tartrate. The metal organic framework compound is prepared from at least one of Zn (C4H7N2) 2, C48H28O32Zr6 or C14H16N2O8Mg2. The invention further discloses a preparation method of the metal organic framework compound. The secondary battery meets the characteristics, and the cycle performance of the secondary battery can be improved.

A positive pole piece and a preparation method therefor, and a secondary battery. The positive pole piece comprises a current collector and a positive electrode active layer. The positive electrode active layer is arranged on at least one surface of the current collector. The positive electrode active layer comprises a first positive electrode active layer at least formed on the current collector, and a second positive electrode active layer formed on the side of the first positive electrode active layer away from the current collector. The first positive electrode active layer comprises lithium iron phosphate particles, and the second positive electrode active layer comprises lithium nickel cobalt manganate particles; or, the first positive electrode active layer comprises lithium nickel cobalt manganate particles, and the second positive electrode active layer comprises lithium iron phosphate particles. The primary average particle size of the lithium iron phosphate particles is 500-3000 nm, and the specific surface area BET of the lithium iron phosphate particles is 3m 2 / g-8m 2 / g. The positive pole piece can reduce gas production when coating the upper and lower layers of the lithium iron phosphate particles and the lithium nickel cobalt manganate particles, and also has good gram capacity.

The invention belongs to the technical field of energy materials, and provides a multi-functional-layer lithium manganate positive electrode material and a preparation method thereof and a lithium battery, the multi-functional-layer lithium manganate positive electrode material comprises a core body and a coating layer, the core body sequentially comprises a bulk-phase-doped lithium manganate matrix, an induction doping layer and a modification doping layer from inside to outside, the chemical general formula of the core body is Li < 1 + a > Mn < 2-b-c-d > M R < c > X < d > O < 4-e > Z < e >, bulk phase doping elements of the matrix are M and Z, a crystal face induction element is X, and a modification doping element is R; the coating layer is a compound comprising a coating element M '; a supported crystal face inducer is also adopted for further inhibiting the growth of the crystal face (111) and reducing the area of the crystal face (111) so as to form the positive electrode material of a polyhedral spinel crystal structure comprising at least 26 crystal faces, and the crystal face inducer comprises a phosphorus-containing compound, a boron-containing compound or at least + 5 valence metal salt; the Mn dissolution reaction is reduced, and the electrochemical performance of the lithium manganate is improved.

The invention discloses a preparation method and application of a positive electrode lithium supplement agent, the positive electrode lithium supplement agent is of a core-shell structure, and a core layer comprises lithium-rich metal materials such as lithium-rich lithium ferrite, lithium-rich lithium nickelate and lithium-rich lithium manganate; and a shell layer comprises organic lithium salt materials such as lithium bis (oxalato) borate, lithium bis (fluorosulfonyl) imide, lithium difluorophosphate and lithium difluorobis (oxalato) phosphate. The lithium-rich metal material lithium supplementing agent is coated with the organic lithium salt lithium supplementing agent which is also used as the lithium supplementing agent, so that the lithium-rich metal material is prevented from being in contact with air, and the environmental stability of the lithium-rich metal material is improved; through chelation of specific groups and transition metal ions, the structural stability of the lithium-rich metal material is improved, a lithium ion transmission path is fixed, the capacity of the lithium supplement agent for the lithium-rich metal material can be exerted to the maximum extent, and the organic lithium salt also has a lithium supplement effect, so that the migration rate of lithium ions can be further improved, and the lithium supplement effect is improved. The lithium supplementing effect of the two lithium supplementing agents greatly improves the energy density and the cycling stability of the battery.

The invention provides a composite lithium manganate positive electrode material, a preparation method thereof, a pole piece and a battery, and relates to the technical field of lithium batteries. The composite lithium manganate positive electrode material is of a core-shell structure; the core is lithium manganate, and the shell is a composite coating layer coating the surface of lithium manganate; the composite coating layer comprises a first coating layer and a second coating layer; the first coating layer is CuCe < x > Fe < 2-x > O < 4-y > Li; and the second coating layer comprises PVDF particles. The invention provides a lithium manganate material with a double-layer core-shell structure. The CuCexFe2-xO4-yLi inner layer reduces impedance and stabilizes crystal lattices by virtue of spinel isomorphism and doping, and anchors the PVDF outer layer based on oxygen vacancy; and in cooperation with the surface lithium gradient effect, the structural stability and electrochemical performance of the material are remarkably improved.

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 field of lithium manganate positive electrode materials, in particular to a lithium manganate positive electrode material and a preparation method thereof, a positive electrode plate and a battery, which are used for solving the problems of Jahn-Teller distortion of Mn < 3 + >, Mn dissolution and low conductivity in circulation. Lithium carbonate, manganous-manganic oxide, potassium carbonate, aluminum nitrate and absolute ethyl alcohol are subjected to ball milling and then sintered to obtain K / Al co-doped lithium manganate powder, then the K / Al co-doped lithium manganate powder is coated with an acetylferrocene / diphenylamine polymer, finally, the K / Al co-doped lithium manganate powder is coated with an AlF3 (at) CeF3 suspension, and finally the lithium manganate positive electrode material is obtained. According to the lithium manganate positive electrode material, the electronic conductivity is greatly improved, the rate capability is improved, and the cycling stability is improved; and the material has excellent cycling stability and rate capability.

The invention discloses a preparation method for recycling and regenerating a Mo / F co-doped manganese-sodium-rich electric ternary positive electrode material from a waste nickel cobalt lithium manganate positive electrode, and relates to a method for synthesizing and regenerating a Mo / F co-doped layered nickel cobalt manganese oxide manganese-rich (Na < 0.67 > Ni < 0.21 > Co < 0.1 > Mn < 0.67 > Mo < x > F < y > O < 2 >) ternary positive electrode material by recycling and reusing a waste power battery and application of the Mo / F co-doped manganese-sodium-rich electric ternary positive electrode material. The method comprises the following steps: leaching a waste ternary positive electrode material by a wet method, co-precipitating, calcining and regenerating to prepare the Mo / F co-doped sodium ion layered transition metal oxide positive electrode material (Na < 0.67 > Ni < 0.21 > Co < 0.1 > Mn < 0.67 > Mo < x > F < y > O < 2 >). An electrochemical test result shows that the positive electrode has excellent normal-temperature performance, and meanwhile, the problem of slow dynamics of the positive electrode at low temperature is broken through. According to the invention, the waste power battery positive electrode is recycled, and is regenerated and converted into the sodium ion battery positive electrode material with abundant raw materials through a modification strategy. A spinel surface layer is formed by introducing Mo / F, and the cycle performance of the layered transition metal oxide positive electrode material of the regenerated sodium-ion battery is improved through the synergistic effect of Mo / F. The preparation process is simple, high in operability, wide in raw material source, low in cost and suitable for large-scale production, and meets environmental requirements.

The invention belongs to the technical field of lithium ion battery electrode materials, and particularly discloses a diameter-controllable one-dimensional lithium manganate nanorod as well as a preparation method and application thereof. The preparation method comprises the following steps: dispersing manganese sulfate, potassium permanganate, a structure-directing agent and a surfactant into a solvent, and carrying out hydrothermal reaction to obtain a black precipitate; sintering the black precipitate to obtain a manganese dioxide nanorod; and mixing the manganese dioxide nanorod with lithium hydroxide, and carrying out two-stage sintering to obtain the one-dimensional lithium manganate nanorod. The prepared lithium ion battery anode material is uniform in thickness and very small in surface energy, can effectively shorten the transmission path of lithium ions when being used as an anode material, is not easy to agglomerate, has good flexibility, can maintain the structural integrity in a large-current long-time service process, and is beneficial to improving the rate and cycle performance of an electrode. In addition, by adjusting the concentration of potassium permanganate and the hydrothermal reaction temperature, the diameter of manganese dioxide can be accurately adjusted, and controllable preparation of one-dimensional lithium manganate is realized.

The invention provides a positive plate and a preparation method thereof, a battery, a battery pack and electric equipment. The positive plate comprises a current collector, and a first active layer and a second active layer which are sequentially stacked on at least one functional surface of the current collector, the first active layer comprises a first active material, a first conductive agent and a first binder; the second active layer comprises a second active material, a second conductive agent and a second binder; the first active material comprises lithium manganate and / or lithium manganese iron phosphate; the second active material comprises a ternary material; the mass ratio of the first active material to the second active material is (5-9): (1-5). According to the positive plate provided by the invention, the double active layers with different compositions are arranged, so that the cycling stability and the storage resistance of the battery can be effectively improved on the premise of not influencing the rate performance of lithium manganate and / or lithium iron manganese phosphate and not losing the development of the battery capacity.

The invention discloses a method for in-situ lossless repair of an attenuated lithium manganate positive electrode material, which specifically comprises the following steps: adding the attenuated lithium manganate material into a lithium hydroxide solution, supplementing lithium to an original value by a hydrothermal method, repairing the component and structure defects of attenuated LiMn2O4 by combining high-temperature roasting, and recycling and regenerating lithium manganate particles with severely attenuated capacity. The lithium manganate positive electrode material is directly recovered by the lossless method, and the chemical components and crystallinity of the invalid positive electrode material in various health states are reconstructed, so that the invalid positive electrode material can be repeatedly used in the lithium ion battery. Finally, the treated recycled powder material is coated by a metal organic framework (MOFs) self-assembly method, so that the electrochemical performance of the treated powder material is further improved. The method is simple, environmentally friendly and low in energy consumption, has obvious advantages compared with a traditional hydrometallurgy battery recovery method, and lays an important foundation for sustainable manufacturing of energy materials.

The invention belongs to the field of preparation of a lithium ion battery positive electrode material, and particularly relates to high-voltage type single crystal lithium manganate, a preparation method and application of the high-voltage type single crystal lithium manganate. According to the scheme, a manganese source compound, a lithium source compound and a transition metal oxide are mixed according to the molar ratio of 1: (0.5-0.6): (0.1-0.3), deoxidized and sintered, and a single-crystal lithium manganate intermediate product is obtained; and preparing a finished product by taking the obtained intermediate product as a raw material. The deoxidation sintering operation comprises the steps of heating from room temperature to 800-1000 DEG C at a heating rate of 20-30 DEG C / min, keeping the temperature for 2-6 hours, not carrying out heat preservation operation in the heating process, cooling to 400-500 DEG C at a cooling rate of 50-100 DEG C / h after the constant temperature stage is ended, and keeping the temperature for 2-4 hours, so as to prepare the high-voltage type single crystal lithium manganate positive electrode material. According to the scheme, the capacity and the high-temperature cycle performance of the lithium manganate material can be remarkably improved and the expansion rate of the battery can be inhibited under the cooperation of the doping elements with rapid heating, gradient cooling and radius matching. Meanwhile, the invention also provides an application of the high-voltage single-crystal lithium manganate positive electrode material in a battery.

The invention provides a positive electrode material and a preparation method thereof, a positive electrode plate and a secondary battery, and belongs to the field of battery materials, the positive electrode material comprises an inner core and a composite coating layer coating the surface of the inner core; the inner core comprises lithium iron phosphate, and the composite coating layer comprises a carbon material and a metal oxide; wherein the metal oxide comprises at least one of lithium titanate, lithium manganate and lithium cobalt oxide. The carbon material and the metal oxide containing titanium, cobalt and manganese are compounded to serve as the composite coating layer to coat the lithium iron phosphate core, on one hand, the microstructure characteristics of the metal oxide containing titanium, cobalt and manganese are utilized, richer channels are provided for lithium ion diffusion, on the other hand, the high electron conductivity of the carbon material is utilized, and the lithium ion diffusion efficiency is improved. The prepared positive electrode material can simultaneously have relatively high electronic conductivity and lithium ion diffusion rate, and when the positive electrode material is used as a lithium ion battery, the charge-discharge performance and the cycle life of the lithium ion battery are remarkably improved.

The invention relates to a composite positive electrode material and a preparation method thereof, a positive plate and a battery in the technical field of lithium battery production. The composite positive electrode material comprises a core part of a lithium manganate positive electrode material and a coating layer positioned on the surface of the core part, the coating layer comprises a first coating layer and a second coating layer, and the first coating layer is positioned between the core surface of the lithium manganate positive electrode material and the second coating layer; the first coating layer is nickel cobalt lithium manganate (NCM), and the second coating layer is lithium iron phosphate (LFP). Through the synergistic protection effect of double-layer coating, the stability of the lithium manganate structure can be remarkably enhanced, and the high-temperature storage performance and the cycle performance of the battery cell are improved.

The application belongs to the field of lithium ion battery cathode material preparation, and particularly relates to a high-voltage type single-crystal lithium manganate, a preparation method and application thereof. The scheme mixes a manganese source compound, a lithium source compound and a transition metal oxide according to a molar ratio of 1:0.5-0.6:0.1-0.3, deoxidizes and sinter, to obtain a single-crystal lithium manganate intermediate product; the obtained intermediate product is used as a raw material to prepare a finished product; the deoxidizing and sintering operation is to raise the temperature from room temperature to 800-1000 DEG C at a temperature raising rate of 20-30 DEG C / min, and keep constant temperature for 2-6 h, no temperature keeping operation is performed in the temperature raising process, after the constant temperature stage is finished, the temperature is lowered to 400-500 DEG C at a temperature lowering rate of 50-100 DEG C / h, and keep constant temperature for 2-4 h, to prepare the high-voltage type single-crystal lithium manganate cathode material. The scheme can significantly improve the capacity and high-temperature cycle performance of the lithium manganate material, and inhibit the battery expansion rate, through fast temperature raising, gradient temperature lowering and the cooperation of radius-matched doping elements. Meanwhile, the application also provides application of the high-voltage type single-crystal lithium manganate cathode material in a battery.

The invention relates to the technical field of lithium extraction from salt lakes, in particular to a lithium iron phosphate-composite lithium manganate composite material for lithium extraction from high-altitude salt lakes and a preparation method of the lithium iron phosphate-composite lithium manganate composite material. The composite material comprises lithium iron phosphate and composite lithium manganate, wherein the composite lithium manganate comprises spinel type lithium manganate and layered lithium manganate. According to the lithium iron phosphate-composite lithium manganate composite material provided by the invention, the adopted composite lithium manganate has a three-dimensional ion conduction channel structure of spinel type lithium manganate and high specific capacity of layered lithium manganate at the same time, and the problem that a single lithium iron phosphate material is relatively poor in conductivity and ion conductivity is solved. And meanwhile, a single type of lithium manganate additive is also avoided, and the lithium extraction efficiency and the lithium extraction capacity of lithium extraction of the high-altitude salt lake are comprehensively improved.

The application belongs to the technical field of lithium ion batteries, and particularly relates to a carbon-nitrogen double-layer coated positive electrode lithium supplementing agent and a preparation method and application thereof. The preparation method of the carbon-nitrogen double-layer coated positive electrode lithium supplementing agent provided by the application is as follows: a carbon source such as sucrose, a nitrogen source such as melamine, and an iron source such as nano-iron oxide are uniformly mixed, and then one-step sintering is performed to make the mixture dehydrate; then in the second-step sintering, a lithium source such as pitch and lithium oxide (Li2O) is introduced to generate lithium ferrite (Li5FeO4), which effectively avoids water generated by dehydration of the carbon source such as sucrose and impurities generated by the reaction of lithium ferrite, improves the purity and performance of the positive electrode lithium supplementing agent, and meanwhile, the carbon-nitrogen double-layer coating can effectively coat the lithium ferrite and introduce nitrogen, thereby improving the stability, ion diffusivity and conductivity of the positive electrode lithium supplementing agent, so as to solve the technical problem of poor performance of the lithium manganate positive electrode lithium supplementing agent prepared by the existing preparation method.

The invention belongs to the technical field of manganous-manganic oxide production, and particularly discloses low-specific-surface-area manganous-manganic oxide and a preparation method thereof.In the process of preparing manganous-manganic oxide through one-step oxidation, the oxygen introduction rate and the stirring linear speed at different reaction stages are accurately adjusted, so that the specific surface area of manganous-manganic oxide is increased, and the specific surface area of manganous-manganic oxide is increased. Furthermore, accurate cooperative control on crystal nucleation and growth processes is realized, so that a manganous-manganic oxide product with a low specific surface area can be stably obtained, and the requirement of a high-performance battery material on the low specific surface area is met. The method can be suitable for reaction equipment of different scales, and is beneficial for realizing large-scale production of products. In addition, the method is short in process, easy to operate, high in production efficiency and stable and controllable in product quality. And the obtained product is low in specific surface area, moderate in particle size, uniform in morphology and relatively high in tap density. The lithium manganate material adopting the product shows excellent cycle performance, the service life of the battery is remarkably prolonged, and the energy density of the battery is remarkably improved.

Provided in the present disclosure is a positive electrode material, containing a positive electrode active material, a conductive agent and a binder, the positive electrode active material consisting of a positive electrode main material and a lithium supplementing agent, the positive electrode main material being selected from at least one of lithium iron phosphate and lithium manganese iron phosphate, and the lithium supplementing agent being selected from at least one of lithium manganate and a lithium-rich manganese-based material. On the basis of the total weight of the positive electrode active material, the mixing weight ratio of the positive electrode main material to the lithium supplementing agent is: 70:30≤positive electrode main material: lithium supplementing agent≤99.9:0.1. A positive electrode coating is formed by means of a double-layer synchronous coating process, the content of the lithium supplementing agent in the surface layer being a wt %, the content thereof in the bottom layer being b wt %, and the total content of the lithium supplementing agent in the positive electrode active material being within the range of 0.1-30%. Correspondingly, further disclosed in the present disclosure is a positive electrode pre-lithiated battery comprising the positive electrode material. The pre-lithiation technology for positive electrode materials of lithium-ion batteries provided by the present disclosure significantly improves the usable cycle capacity, rate capability and cycle stability of batteries, and has important application value and promotion prospects.

The invention discloses a lithium titanate battery, and relates to the technical field of batteries. The battery comprises a positive electrode, a negative electrode, an electrolyte and a diaphragm, and an addition product synthesized by dimethyl fumarate and benzidine according to a specific molar ratio is added into the electrolyte as a viscosity modifier, so that the viscosity increasing trend of the electrolyte at a low temperature is effectively reduced, and the migration rate of lithium ions is improved. And the electrolyte also comprises a lithium salt, an organic solvent and an auxiliary additive, so that the low-temperature performance and the cycling stability of the battery are favorably optimized. A positive active material is one or more of lithium iron phosphate, lithium manganate, lithium cobalt oxide or nickel manganese cobalt ternary materials, a negative active material is lithium titanate, and additives such as lithium nitrate and fluoroethylene carbonate are further combined, so that the capacity retention ratio and the charge-discharge efficiency of the battery in an extreme low-temperature environment of-40 DEG C are remarkably improved. The lithium titanate battery provided by the invention has excellent low-temperature adaptability, safety and long cycle life, and is applicable to power batteries and energy storage systems in alpine regions.

The invention provides a preparation method and application of a low-cost single-crystal lithium manganate positive electrode material, and belongs to the technical field of lithium ion battery positive electrode materials, preferably, low-cost manganese carbonate is adopted as a raw material, firstly, manganese carbonate and a cracking agent are mixed and then pyrolyzed to prepare high-activity manganese dioxide, and the high-activity manganese dioxide is prepared into a single-crystal lithium manganate positive electrode material. Then manganese dioxide is mixed with lithium salt and a lattice stabilizer and then subjected to high-temperature heat treatment, the single-crystal lithium manganate positive electrode material is prepared, when manganese dioxide is prepared, manganese carbonate is decomposed and can release gas to be pulverized, meanwhile, PVP is used in a combined mode, a self-heating, soft and porous decomposition environment is formed, decomposition of manganese carbonate is promoted, and the manganese granularity is refined; manganese dioxide particles obtained by decomposition are uniform and fine and have high activity; the preparation method provided by the scheme is easy to industrialize, and the product has the characteristics of low cost, low manganese dissolution and excellent electrochemical performance.

The invention relates to the technical field of lithium ion batteries, in particular to a nickel cobalt lithium manganate positive electrode material and a preparation method thereof. According to the invention, the technical problems of poor cycle performance and low specific capacity of the existing nickel cobalt lithium manganate positive electrode material are solved. The preparation method comprises the following steps: synthesizing precursor powder by adopting a coprecipitation process; then carrying out high-shear mixing on the precursor, lithium hydroxide, nano niobium oxide and magnesium fluoride; after the mixed material is subjected to pre-oxidation and high-temperature oxygen-enriched gradient sintering, a gradient reduction etching process is adopted in the cooling stage, and strong wind quenching is matched for surface shaping; and finally, carrying out air jet pulverization and demagnetization to obtain the nickel cobalt lithium manganate positive electrode material. According to the method, lattice respiration stress is effectively dissipated by constructing a radial ordered structure, a bulk phase structure is stabilized through multi-element synergistic doping, interfacial ion transport kinetics is optimized through reduction-induced surface oxygen vacancies and a lattice distortion layer, and the synergistic strategy ensures high stability of the material structure and meanwhile, the material structure has a good application prospect. And the de-intercalation efficiency of the active lithium is greatly improved.

The invention discloses a lithium manganate conductive material and a preparation method thereof, and the lithium manganate conductive material comprises a lithium manganate inner net layer which is a nano network layer formed by connecting lithium manganate crystal grains; the graphene and / or carbon nanotube conductive carbon outer net layer is deposited on the surface of the inner net layer. The lithium manganate crystal grains are uniform and fine, and the crystal grains are of a continuous net-shaped arrangement structure. Dissolving and mixing the polymer nanofiber, manganese salt, lithium salt and M-doped salt to form gel, drying, and carrying out two-stage programmed heating calcination in an oxygen-containing atmosphere to obtain a lithium manganate nano inner net layer; ultrasonically dispersing the lithium manganate nano inner net layer in water, adding acidified carbon nanotubes and / or graphene oxide dispersion liquid, and depositing the acidified carbon nanotubes and / or graphene oxide dispersion liquid on the surface of the inner net layer to form a conductive carbon outer net layer. The obtained lithium manganate conductive material has a continuous large-area two-dimensional network structure, shows high conductivity, high specific capacity and excellent cycling stability, and can be widely applied to the fields of lithium ion batteries, electrochemical lithium extraction, lithium ion adsorption and the like.

The application belongs to the technical field of inorganic nanometer material preparation, and particularly relates to a hollow manganese dioxide / cobalt manganate loaded nitrogen-doped carbon hybrid material and a preparation method thereof. The steps of the application are as follows: S1, dispersing manganese source material in N,N-dimethylformamide to form a uniform solution; S2, adding an organic ligand to the solution obtained in step S1 and continuously stirring to obtain a mixed solution, and then transferring the mixed solution to a reaction kettle for a solvothermal reaction; S3, sequentially washing and drying the product obtained through the solvothermal reaction, and then grinding the product and a cobalt salt to form a mixture powder; and S4, performing a high-temperature pyrolysis reaction on the mixture powder, and obtaining the hollow manganese dioxide / cobalt manganate loaded nitrogen-doped carbon hybrid material rich in mesopores and macropores after the reaction stops. The application has a large specific surface area and a multi-pore structure, slows down the migration and aggregation of metal particles and the loss of pyrolysis intermediates in the heat treatment process, and improves the electrochemical activity and stability of the transition metal / nitrogen-doped carbon electrocatalyst.

The invention discloses a preparation method and application of hollow lithium manganate microspheres based on a sound-induced microbubble template, and belongs to the field of lithium ion batteries. The method comprises the following steps: dissolving a surfactant in deionized water to prepare a surfactant solution with the concentration of 1-2g / L; high-power ultrasonic waves are applied to the surfactant solution, micron-sized bubbles are generated in the surfactant solution, and microbubble template liquid is obtained; adding manganese salt and an oxidizing agent into the microbubble template liquid under the continuous action of ultrasound, so that the manganese salt is oxidized at a gas-liquid interface of the micron-sized bubbles to form a hollow manganese dioxide precursor; centrifugally collecting, washing and drying to obtain hollow manganese dioxide microspheres; the hollow manganese dioxide microspheres and a lithium source are uniformly mixed and then subjected to segmented heat treatment, and the hollow lithium manganate microspheres are obtained after natural cooling, so that the problems that the template removal step is tedious, impurities are possibly introduced, the temporary template stability is poor, and the size distribution is non-uniform are solved.