625 results about "Manganate" patented technology

The invention provides a battery monomer, a battery device and a power utilization device. The battery monomer comprises an electrode assembly, wherein the electrode assembly comprises a positive plate, a negative plate and a non-aqueous electrolyte; the positive plate comprises a positive current collector and a positive film layer, and the negative plate comprises a negative current collector and a negative film layer; the positive electrode film layer comprises a positive electrode active material, and the positive electrode active material comprises a lithium manganese iron phosphate material and a nickel cobalt lithium manganate material; in the nickel cobalt lithium manganate material, the molar ratio of Ni in the sum of the three elements of Ni, Co and Mn is 0.5-0.95; the non-aqueous electrolyte comprises vinylene carbonate, and the mass content of the vinylene carbonate in the non-aqueous electrolyte is 0.5%-2%; the non-aqueous electrolyte comprises at least one of linear carbonic ester and linear carboxylic ester, and the conductivity of the non-aqueous electrolyte is 9-14 mS / cm. The energy density, the cycle performance and the power performance of the battery monomer are improved at the same time.

The invention provides a manganese-based composite positive electrode material and a preparation method and application thereof. The manganese-based composite positive electrode material has a core-shell structure; the core of the core-shell structure is made of a lithium manganate material, and the shell is made of a lithium-rich manganese-based positive electrode material. Compared with the prior art, a manganese-based composite positive electrode material precursor with the inner core mainly comprising manganese and the outer shell mainly comprising nickel, cobalt and manganese is prepared in situ by adopting a coprecipitation method, and then pre-oxidation, lithium mixing and sintering modification are performed; the high-capacity, high-safety, long-circulation and high-compaction manganese-based composite positive electrode material of which the core is the lithium manganate material and the shell is the lithium-rich manganese-based positive electrode material is obtained, so that the problems of cycling stability and high-temperature storage of the manganese-based positive electrode material are solved; furthermore, the manganese-based composite positive electrode material is used as the positive electrode material of the lithium ion battery, so that the lithium ion battery with high energy density, long service life and high safety can be prepared.

The invention discloses a salt leaching-extraction method for recycling lithium iron phosphate and ternary lithium battery powder through cascade circulation, and belongs to the technical field of waste lithium battery recycling. According to the method, ferric salt is adopted as a leaching agent, a circulation mechanism is constructed through iron ion valence state conversion, and cascade leaching circulation of waste lithium iron phosphate and nickel cobalt lithium manganate battery powder is achieved. A concentrated enrichment liquid containing lithium, nickel, cobalt and manganese, iron phosphate and a graphite crude product can be obtained through multiple leaching cycles. In the leaching circulation process, a mixed solvent is developed as an extraction agent of iron ions, and after extraction and hydrochloric acid reverse extraction are carried out on a leaching solution containing iron salt, the leaching agent and the extraction agent can be recycled. According to the method, the valuable metal in the waste battery powder is efficiently leached under the milder reaction condition, consumption of chemicals such as acid and alkali, a leaching agent, an oxidizing agent and an extracting agent is effectively reduced through research of a circulation mechanism, the cost is remarkably reduced, and good environmental benefits and economic benefits are achieved.

The invention provides a positive pole piece. The positive pole piece comprises a positive current collector, a first material layer arranged on at least one surface of the positive current collector, and a second material layer arranged on the surface, far away from the positive current collector, of the first material layer, the first material layer comprises an active material A and an active material B; the second material layer comprises an active material C; the active material A is selected from lithium iron phosphate and / or lithium manganese iron phosphate; the active material B is selected from one or more of nickel cobalt lithium manganate, lithium cobalt oxide, lithium manganate and nickel lithium manganate; the active material C is selected from one or more of nickel cobalt lithium manganate, lithium cobalt oxide, lithium manganate and nickel lithium manganate; by using the positive pole piece provided by the invention, the interface impedance of the pole piece can be reduced, the problem that the expansion rates of different areas of the pole piece are different is solved, and the cycle life of the battery is prolonged.

The invention provides a positive active material and a preparation method thereof, a positive plate and a battery. The positive electrode active material satisfies the following condition: # imgabs0 #, wherein I (111), I (222), I (400) and I (440) are all not 0. According to the positive electrode active material provided by the invention, the exposure degrees of the crystal face (222) and the crystal face (111) relative to the crystal face (110) and the crystal face (100) are limited by the formula 1, so that the lithium ion conduction rate and the dynamic performance of lithium nickel manganese oxide can be improved, and the rate capability and the discharge capacity of a corresponding battery can be remarkably improved.

The invention provides a positive electrode active material, positive electrode slurry, a positive plate, a battery and a vehicle, and belongs to the technical field of batteries, the positive electrode active material comprises lithium manganese iron phosphate and nickel cobalt lithium manganate; wherein the mass ratio of the lithium manganese iron phosphate to the nickel cobalt lithium manganate is (50-95): (5-50); the chemical general formula of the nickel cobalt lithium manganate is LiNiaCobMn (1-a-b) O2, a is more than or equal to 0.6 and less than 1, b is more than 0 and less than 0.5, and a + b is more than 0 and less than 1. According to the present invention, the lithium manganese iron phosphate and the nickel cobalt lithium manganate are compounded to serve as the positive electrode active material, and the mass ratio of the lithium manganese iron phosphate to the nickel cobalt lithium manganate is controlled within the range of (50-95): (5-50), such that when the positive electrode active material is applied to the battery, the high safety performance can be provided while the high energy density is provided so as to improve the comprehensive performance.

The invention provides a large-area coated lithium manganate positive electrode material and a preparation method thereof, and belongs to the technical field of energy materials, and the large-area coated lithium manganate positive electrode material comprises a lithium manganate positive electrode material body subjected to grain boundary pretreatment and a coating layer coating the surface of the lithium manganate positive electrode material body. The general molecular formula of the lithium manganate positive electrode material body subjected to grain boundary pretreatment is Li < 1 + a > Mn < 2-b > MbO4, M is a doping element, a is more than or equal to-0.1 and less than or equal to 0.3, and b is more than or equal to 0 and less than or equal to 0.3; the surface coating layer comprises an M'coating element. The lithium manganate positive electrode material body subjected to grain boundary pretreatment can realize large-area coating, and the lithium manganate positive electrode material subjected to special grain boundary pretreatment and large-area coating has excellent structural stability, so that corrosion of an electrolyte to lithium manganate is relieved, Mn dissolution at a high temperature is inhibited, and the lithium manganate positive electrode material has good electrochemical performance. Therefore, the lithium manganate positive electrode material has excellent high-temperature circulation and high-temperature storage performance, and the method is simple in process and can be implemented and popularized.

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 a positive electrode active material as well as a preparation method and application thereof. The positive electrode active material comprises secondary particles consisting of primary particles, each primary particle comprises an inner core and a carbon coating layer arranged on at least part of the surface of the inner core; the inner core comprises a solid solution formed by lithium iron manganese phosphate and lithium manganate; the primary particles comprise primary particles A and primary particles B, the particle size of the primary particles A is 50-200nm, and the median particle size D50 is 80-120nm; the particle size of the primary particles B is 400-800 nm, and the median particle size D50 is 500-600 nm. The positive electrode active material has relatively high powder compaction density and ion transmission capability, and the electrochemical performance and energy density of the lithium ion battery can be effectively improved.

The invention discloses a method for synthesizing a lithium nickel manganese oxide positive electrode material through rapid Joule thermal shock. The precursor is loaded on a conductive substrate for Joule thermal shock treatment, so that not only can rapid synthesis within several minutes be realized, but also the product has more oxygen vacancy defects due to the characteristic of rapid heating and cooling of Joule heat, and the number of the oxygen vacancy defects can be further changed by changing the Joule thermal shock treatment time; therefore, the Mn < 3 + > content and the disorder degree of the material structure are influenced, and the optimization of the electrochemical performance is realized. According to the invention, efficient and fine regulation and control of oxygen vacancy number, Mn < 3 + > content and structure disorder degree in the LiNi0. 5Mn1. 5O4 material can be realized, and the high-performance LiNi0. 5Mn1. 5O4 material with the capacity retention rate up to 90.8% after 500 cycles under 1C multiplying power and the capacity of 75mAh / g under 5C multiplying power can be synthesized.

The invention relates to an automatic monitoring technology, and provides a permanganate index detection method and an on-line monitoring method.The permanganate index detection method comprises the steps that a first reagent is prepared, and a mixed solution containing 98% of sulfuric acid, anhydrous manganese sulfate and pure water is prepared into a mixed solution containing 10-25% of sulfuric acid; the method comprises the following steps: adding a quantitative reagent I into a water sample, and heating and digesting to 90-100 DEG C; dropwise adding a potassium permanganate solution, stirring at the speed of 280-350 revolutions per minute, and then keeping at the temperature of 90-100 DEG C for 10 minutes; dropwise adding a sodium oxalate solution, and uniformly stirring; dropwise adding a potassium permanganate solution again and stirring at the same time, and judging a titration end point according to the absorbance of the solution; and calculating the permanganate index according to the drop number at the titration end point. A certain amount of anhydrous manganese sulfate reagent is added into the sulfuric acid reagent, water bath heating is not needed, and the preparation method is simpler and easier to operate than a national standard method. The real drop number of the titration end point is obtained through the equation, so that the titration drop number is more accurate and is accurate to four decimal points.

The invention belongs to the technical field of lithium batteries, and particularly relates to a lithium manganate positive electrode material, a preparation method thereof and a lithium battery, and the method comprises the following steps: adding a manganese sulfate solution, a precipitator and a complexing agent into a reaction kettle in a parallel flow manner, reacting under a first preset reaction condition, and introducing a first oxidant while reacting to obtain a mixed solution; concentrating the mixed solution to preset solid content, and adding a curing agent for curing reaction to obtain manganous-manganic oxide slurry; adding a manganese sulfate solution, a precipitant and a complexing agent into the reaction kettle in a parallel flow manner again, reacting with the manganous-manganic oxide slurry under a second preset reaction condition, introducing a second oxidizing agent while reacting to obtain a composite manganese oxide mixed solution, and filtering, washing and drying to obtain a composite manganese oxide; the composite manganese oxide and lithium carbonate are mixed, calcined, crushed and graded to obtain the lithium manganate positive electrode material, so that the electrochemical performance of the lithium manganate positive electrode material is improved.

The invention discloses a lithium nickel manganese oxide positive electrode material, a preparation method thereof and a battery, and belongs to the technical field of battery materials. The method comprises the following steps: mixing a nickel-manganese precursor with a lithium source and a doping agent, sintering for the first time, crushing by a jet mill and sintering for the second time. The dopant is selected from at least one of ZrO2, Cr2O3 and Y2O3, and the mass of the dopant is 0.5%-5% of that of the nickel-manganese precursor. By adopting the dopant, the chemical and structural stability of the lithium nickel manganese oxide can be improved, and meanwhile, the generation of an oxygen defect auxiliary rock salt phase is induced; the material obtained by the first sintering is subjected to jet mill crushing, so that the position where a rock salt phase is generated can be crushed, and then the second sintering is performed, so that the oxygen defect generated during the first high-temperature sintering can be filled, the damaged lithium nickel manganese oxide bulk phase can be recovered, the rock salt phase can be retained and solidified, and the dissolution of Mn in lithium nickel manganese oxide can be slowed down; and the cycle and storage performance of the battery prepared from the positive electrode material can be improved.

The invention belongs to the technical field of battery materials, and particularly discloses preparation and application of a strontium lanthanum manganate-coated lithium ferric manganese phosphate composite material, and the method comprises the following steps: firstly, preparing strontium lanthanum manganate by adopting a lanthanum source, a strontium source and a manganese source as raw materials; respectively adding a lithium source, a phase transfer agent, a phosphorus source, L-ascorbic acid, an iron source and a manganese source into a solvent, and preparing a lithium ferric manganese phosphate precursor by using a solvothermal method; the lithium ferric manganese phosphate material is coated twice through strontium lanthanum manganate and carbon. According to the invention, strontium lanthanum manganate is used as a coating material, and the addition of lanthanide elements improves the crystal stability of lithium ferric manganese phosphate, keeps the integrity of an olivine-type structure, and avoids capacity fading caused by structure collapse, thereby improving the cycle stability of the lithium ion battery.

The invention provides a lithium manganate precursor with a crystal face induction effect, a preparation method of the lithium manganate precursor, a positive electrode material and a lithium battery, and belongs to the technical field of energy materials, the lithium manganate precursor can play a crystal face induction role in the subsequent lithium mixing sintering process, the lithium manganate precursor is spherical-particle manganous-manganic oxide, the particle size D50 is 3-15 microns, and the particle size D50 is 3-15 microns. The primary particles are uniform in size. The core advantage of the method is that synchronous and uniform doping of the element M and the element M'is realized at the precursor stage through a coprecipitation method. The co-precipitation doping technology not only ensures the atomic-scale uniform distribution of doping elements in manganous-manganic oxide, but also effectively stabilizes the crystal structure of the lithium manganate positive electrode material by utilizing the synergistic effect of the elements in the subsequent sintering process, and realizes the selective induced growth of the crystal face. The unique crystal face induction effect has significant contribution to improvement of the electrochemical performance, including cycling stability, rate capability and safety, of the positive electrode material.

The invention relates to the technical field of lithium ion batteries, in particular to a high-safety nickel cobalt lithium manganate semi-solid battery and a preparation method thereof, and the high-safety nickel cobalt lithium manganate semi-solid battery comprises a positive electrode, a negative electrode, a double-gradient functional layer composite diaphragm and a high-safety electrolyte; the positive electrode comprises a positive electrode current collector and a modified nickel cobalt lithium manganate positive electrode material on the surface of the positive electrode current collector, the modified nickel cobalt lithium manganate positive electrode material comprises a modified nickel cobalt lithium manganate active material, a positive electrode conductive agent, a positive electrode binder and an inorganic solid electrolyte, and the modified nickel cobalt lithium manganate active material comprises a core body and a shell layer; the core body is a Ti and F gradient doped NCM core body, and the shell layer is of a Li2TiO3 / LiAlXB1-xO2 composite double-layer coating structure; the double-gradient functional layer composite diaphragm is of a sandwich double-gradient structure and comprises a base layer located in the middle, and a negative electrode side gradient layer and a positive electrode side gradient layer which are attached to the two side faces of the base layer respectively. The semi-solid battery has the advantages of high energy density, long cycle stability and high safety.

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 invention discloses a high-nickel lithium-rich manganese-based all-solid-state battery positive electrode material which comprises a nickel cobalt lithium manganate inner core and a NiO layer coated on the surface of the inner core, in the high-nickel lithium-rich manganese-based all-solid-state battery positive electrode material, the weight percentage of NiO is 1-5%. The positive electrode material is nickel cobalt lithium manganate with the surface coated with the NiO layer, the NiO coating layer with high chemical stability on the surface of the positive electrode material can serve as a protective layer at a positive electrode / electrolyte interface, on one hand, lattice oxygen on the surface of the positive electrode material can be stabilized, and phase degradation of the positive electrode material in the circulation process is reduced; on the other hand, the material can be used as a buffer layer to limit direct contact between the positive electrode material and the solid electrolyte, thereby weakening side reaction between the positive electrode material and the solid electrolyte and finally improving specific capacity and cycle performance of the solid-state battery. The invention also discloses a preparation method of the high-nickel lithium-rich manganese-based all-solid-state battery positive electrode material, the all-solid-state battery positive electrode material and an all-solid-state battery.

The invention provides a positive pole piece, a preparation method and a secondary battery. The positive pole piece comprises a current collector and a positive active layer, the positive active layer is arranged on at least one surface of the current collector, and the positive active layer comprises a first positive active layer at least formed on the current collector and a second positive active layer formed on the side, away from the current collector, of the first positive active layer, the first positive electrode active layer comprises lithium iron phosphate particles, and the second positive electrode active layer comprises nickel cobalt lithium manganate particles; or, the first positive electrode active layer comprises nickel cobalt lithium 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 3-8 m < 2 > / g. According to the positive pole piece disclosed by the invention, the gas production degree of the upper and lower layers of the lithium iron phosphate particles and the nickel cobalt lithium manganate particles can be reduced, and meanwhile, the positive pole piece also has relatively good gram volume.

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 belongs to the technical field of new energy materials, and discloses a method for preparing special high-purity manganous-manganic oxide for high-end lithium manganate from manganese sulfate, which is characterized in that manganese sulfate is used as a raw material, seed crystals are prepared firstly and then subjected to oxidative synthesis to enable the seed crystals to grow slowly, any additive is not needed, complex procedures such as roasting, crushing and the like are removed, and the method is suitable for industrial production. The manganous-manganic oxide particles with different particle sizes can be prepared, the prepared manganous-manganic oxide product is high in sphericity degree, controllable in particle size distribution, high in tap density and low in specific surface area, and the process has the advantages of being high in automation degree, improving the physical and chemical properties of manganous-manganic oxide, reducing the impurity content in the product and the like.

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 provides a preparation method and application of modified'sea urchin type 'manganous-manganic oxide, ammonia water is used as a main precipitator, manganese sulfate, the precipitator and a complexing agent are added into an alkaline base solution, filtering, washing and drying are performed after reaction to obtain'sea urchin type' manganous-manganic oxide, and the modified'sea urchin type 'manganous-manganic oxide is obtained by modifying the surfaces of particles on the basis. Al, Mg, Ti, Zn and other elements are introduced through liquid phase doping, a wrapping layer is formed on the surface of the sea urchin type manganous-manganic oxide, and the electrochemical performance and stability of the lithium manganate material can be further improved. The invention provides modified sea urchin-type manganous-manganic oxide with primary crystal grains larger than 300 nm, and the manganous-manganic oxide can effectively reduce the erosion effect of electrolyte by means of high-crystallinity and large-size conical crystal grains.

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 provides a leaching method and a recycling method of metal in a nickel cobalt lithium manganate positive plate. The leaching method comprises the following steps: pre-treating a nickel cobalt lithium manganate positive plate disassembled from a waste battery to obtain positive powder; preparing a gluconic acid leaching agent containing gluconobacter oxydans, and electrolyzing the positive electrode powder at the voltage of 2.0-2.5 V by adopting a double-chamber electrochemical electrolytic tank to obtain a leaching solution containing Li < + >, Ni < 2 + >, Co < 2 + > and Mn < 2 + >. Positive electrode powder, a gluconic acid leaching agent and a ferrous sulfate aqueous solution are put into a cathode chamber of a double-chamber electrochemical electrolytic tank, and an inorganic alkali aqueous solution is contained in an anode chamber of the double-chamber electrochemical electrolytic tank; the leaching efficiency can be improved and the leaching rate is high through the effects of dissolution of gluconic acid, electrolysis for hydrogen release and auxiliary reduction of Fe < 2 + >.