82 results about "Oxide cathode" patented technology

Some embodiments are directed to systems and methods for direct recycling of batteries. In one aspect, a method includes obtaining spent cathode materials from spent batteries. The method includes wet milling the spent cathode materials in an aqueous medium to obtain deagglomerated particles. The method includes spray drying the deagglomerated particles to obtain a plurality of clusters of particles. The method further includes annealing the plurality of clusters of particles in a gaseous environment to obtain a plurality of single particles.

The invention provides a composite sodium ion battery layered oxide positive electrode material and a preparation method thereof, the positive electrode material comprises an O3 type core layer material and a P2 type shell layer material, the chemical formula of the O3 type core layer material is NahNiiMnjFekZr1-i-j-kO2, 0.95 < = h < = 1.15, 0.25 < = i < = 0.4, 0.25 < = j < = 0.4, 0.25 < = k < = 0.4, 0.05 < = 1-i-j-k < = 0.15. The chemical formula of the P2 type shell layer material is Na < 0.7 > Ni < 0.37-p > Mg Mn < 0.63-q-r > Ti < q > Sn < r > O2, p is greater than or equal to 0.01 and less than or equal to 0.07, q is greater than or equal to 0.01 and less than or equal to 0.15, and r is greater than or equal to 0.01 and less than or equal to High charge-discharge specific capacity is provided through the O3 type core layer material, good air stability is provided through the P2 type shell layer material, and the cycle stability of the core layer material is improved by doping the zirconium element in the O3 type core layer material; by doping magnesium, titanium and tin elements in the P2 type shell material, the complex phase change of the shell material in the charge-discharge cycle process is inhibited, and the cycle stability of the shell material is improved, so that the positive electrode material has high charge-discharge specific capacity and keeps good air stability and high cycle stability at the same time.

The application discloses a synthesis method of a large single-crystal sodium-ion battery layered oxide positive electrode material, and comprises the following steps: (1) weighing metal oxides containing transition metal elements, transferring to a device with mixing functions, uniformly mixing, and obtaining a metal oxide mixture; (2) adding acid to the metal oxide mixture, fully mixing, and completing an acid treatment process; (3) adding alkali to the mixture after acid treatment, fully mixing; (4) transferring the mixture obtained in the step (3) to a calcining furnace, high-temperature calcining, and obtaining a layered oxide. The acid treatment process is introduced, the surface of the metal oxide forms a defect structure under the action of the acid, and the defect structure is more beneficial to the formation of strong interaction between each component of the metal oxide and between the metal oxide and sodium-containing alkali, so that a larger single-crystal layered oxide structure is finally formed, and the specific capacity, rate performance and cycle performance are excellent.

The application belongs to the technical field of lithium ion batteries, and particularly relates to a kind of one-dimensional LiNi 1 / 3 Co 1 / 3 Mn 1 / 3 O2 ternary layered oxide positive electrode material and a preparation method thereof, which comprises the following steps: adding a nickel salt, a cobalt salt and a manganese salt into water, stirring and dissolving to obtain a solution A; adding LiMn2O4 into the solution A and stirring uniformly to obtain a solution B; mixing a lithium salt with water to obtain a solution C, and under stirring, adding the solution C into the solution B to obtain a solution D; evaporating the solution D under stirring to obtain a precursor powder; and sintering the precursor powder at 400-600 DEG C, and then sintering at 750-850 DEG C to obtain the positive electrode material. 1 / 3 Co 1 / 3 Mn 1 / 3 O2 material.

This invention belongs to the technical field of sodium-ion battery electrode materials, specifically relating to a preparation method and application of an air-stable molten asphalt-coated sodium selenide composite cathode sodium replenisher. The invention first prepares pure-phase sodium selenide nanoparticles in a glove box by room temperature stirring. Then, asphalt is grown in situ on the surface of the sodium selenide through ball milling and high-temperature calcination, thereby forming a core-shell structured sodium selenide composite sodium replenisher material coated with molten asphalt. The resulting composite sodium replenisher is stable in air for extended periods without deterioration, while simultaneously reducing the decomposition potential of sodium selenide and improving its decomposition efficiency. Coupled with a layered oxide cathode, it can achieve cathode sodium replenishment, compensating for the loss of active sodium caused by the growth of the SEI film on the surface of the hard carbon anode. Furthermore, its decomposition product, selenium, can inhibit the lattice oxygen evolution of the layered oxide cathode, improving the structural stability of the cathode and thus effectively enhancing the battery's initial efficiency and cycle performance, demonstrating promising commercial application prospects.

This invention discloses a monocrystalline cathode material for sodium-ion batteries, its preparation method, and its applications. The preparation method of this monocrystalline cathode material includes the following steps: mixing and sintering waste materials and / or precursor materials with molten salt to obtain a molten salt sintered product; washing the molten salt sintered product with a salt solution, followed by filtration and drying to obtain the monocrystalline cathode material for sodium-ion batteries. This invention is based on molten salt technology, introducing salt solution washing during the washing stage. Based on solvation structure regulation, it inhibits the damage of water molecules to the oxide cathode material, thereby achieving the cleaning of excess molten salt while maintaining the structural integrity of the newly prepared material. The method of this invention has the characteristics of low cost, simple process, and wide applicability. It can realize the unified recycling of waste materials in different states or the direct sodium intercalation of precursor materials, providing technical support for the closed-loop development of the sodium-ion battery industry.

This invention discloses an O3-phase high-entropy layered oxide cathode material, its preparation method, and its application, belonging to the technical field of sodium-ion battery cathode materials. The O3-phase high-entropy layered oxide cathode material has the chemical formula NaNi. 1‑ 8x Ca x Co x Al x Fe x Mn x Si x Ti x Zr x O2, x = 0.05~0.1. Raw materials are weighed according to stoichiometric ratio, mixed, and pulverized to obtain precursor powder. The precursor powder is then sintered in a pure oxygen atmosphere to obtain a first sintered product, which is then pulverized again. The pulverized product is then sintered in a pure oxygen atmosphere for a second step, and after cooling, an O3 phase high-entropy layered oxide cathode material is obtained. Sodium-ion batteries assembled based on this cathode material exhibit excellent high-rate performance and long-cycle stability.

This invention belongs to the field of sodium-ion battery material technology, specifically relating to a multiphase heterostructure sodium-ion battery metal oxide cathode material and its preparation method. The metal oxide cathode material of this invention is composed of at least two crystal phases selected from monoclinic P′3, cubic, hexagonal P2, and hexagonal P3. The preparation process includes: dissolving Ni and Mn sources in deionized water, adding a precipitant and ethylene glycol, and obtaining a precursor through a hydrothermal reaction; mixing the precursor with Co, Cu, and Na sources, and calcining to obtain the metal oxide cathode material. The multiphase heterostructure prepared by this invention is highly controllable, the operation process is simple, and it is applicable to other synthesis methods, thus facilitating industrial production. The obtained cathode material can mitigate structural distortion caused by phase transitions during charging and discharging, and improve the Na+ efficiency. + Reaction kinetics, thereby achieving excellent rate performance and cycle stability.

This invention belongs to the field of lithium battery material technology, specifically relating to a metal oxide / mesoporous manganese dioxide / conductive polymer composite material, its preparation method, and its application. The preparation method includes the following steps: 1) ball milling a commercial metal oxide; 2) mixing the metal oxide powder with an organic polymer monomer and a methyl orange solution and ultrasonically dispersing the mixture to obtain a liquid mixture; 3) adding a potassium permanganate solution to the liquid mixture and performing a high-pressure hydrothermal reaction under stirring to obtain the composite material; 4) subjecting the composite material to alkali treatment, filtering, washing with water, and drying to obtain the metal oxide / mesoporous manganese dioxide / conductive polymer composite material. This metal oxide / mesoporous manganese dioxide / conductive polymer composite material can be used to prepare lithium battery cathode materials with high specific capacity, high conductivity, and high stability in a simple, efficient, and low-cost manner. It is easy to industrialize and solves the problems of low conductivity and poor rate discharge performance of traditional metal oxide cathode materials.

The embodiment of the invention relates to a high-voltage stable sodium-electrode layered oxide positive electrode material as well as a preparation method and application thereof. The positive electrode material comprises a titanium-based sodium ion layered oxide positive electrode material NaxTiaMbO2 which is formed on the surface of the material in situ through one-time sintering and has a cubic phase with the thickness smaller than 5 nm, and the weighted average ion potential phi M of other cations except sodium ions in the positive electrode material NaxTiaMbO2 is adjusted to meet the condition that phi M is larger than 50.5 nm <-1 > and smaller than or equal to 51.9 nm <-1 >, therefore, the bonding effect of transition metal and oxygen in the layered oxide positive electrode material of the sodium ion battery is adjusted, and a bulk phase structure of the positive electrode material is formed; m in the positive electrode material NaxTiaMbO2 is a transition metal element and comprises at least four elements; the at least four elements comprise Ni < 2 + >, Mn < 4 + >, and at least two of Li < + >, Cu < 2 + >, Al < 3 + > and Fe < 3 + >; and the positive electrode material NaxTiaMbO2 satisfies electric neutrality and satisfies 0.9 < = x < = 1.05, 0.05 < = a < = 0.3 and a + b = 1.

The invention discloses a method for preparing a sodium-ion battery high-entropy oxide positive electrode material from a red mud extract, and relates to the technical field of battery positive electrode material preparation. According to the method, the red mud is used as one of main raw material sources, aluminum, iron, titanium and magnesium elements naturally coexisting in the red mud are used as multi-metal component precursors, sodium, nickel and manganese elements are introduced as additional components, and a high-entropy oxide positive electrode material system is constructed through multi-element cooperative regulation and control. The preparation method comprises the steps of red mud pretreatment, uniform mixing with an external metal source, thermal activation treatment, sodium source introduction, mechanical ball milling, high-temperature sintering and the like, and the multi-component high-entropy oxide positive electrode material with the layered structure is prepared. In the material, various metal elements are distributed in crystal lattices in a highly disordered manner, a stable high-entropy structure is formed, phase separation and structural collapse are effectively inhibited, and the structural stability and electrochemical reaction kinetics performance of the material in the charging and discharging process are improved.

A method for preparing an air-stabilized sodium-ion battery cathode material with in-situ phosphate coating is disclosed. This method addresses the technical problems of poor moisture resistance and low cycle retention in existing layered oxide cathodes. The material of this invention involves in-situ coating of phosphate onto the surface of a layered oxide-type sodium-ion battery cathode material and gradient doping of metal ions into the material's interior. Preparation method: Layered oxide-type sodium-ion battery cathode material particles, a phosphorus source, and a metal source are mixed in NMP, followed by drying and calcination to obtain the cathode material. O3-NaNi is used as the air-stabilized coating layer with sodium calcium phosphate. 1 / 3 Fe 1 / 3 Mn 1 / 3 The initial capacity of O2 after 3 days of exposure to 50% humidity was 100.35 mAh g. ‑1 At 1C rate, the capacity retention rate after 200 cycles is 84.06%, which is 36.99% and 12.60% higher than that of the uncoated battery, respectively; it can be used in the field of sodium-ion batteries.

The invention discloses preparation and application of a layered oxide positive electrode material of a high-rate sodium-ion battery, and particularly relates to the technical field of sodium-ion batteries, the chemical formula of the layered oxide positive electrode material of the high-rate sodium-ion battery is NaxN iaCobFecMndAeO2, and x is greater than or equal to 0.9 and less than or equal to 1.05; 0 < = a < = 0.4; 0 < = b < = 0.4; 0 < = c < = 0.4; 0 < = d < = 0.4; 0 < = e < = 0.4, and a + b + c + d + e = 1. The preparation method comprises the following steps: mixing a sodium source, a nickel source, a cobalt source, an iron source, a manganese source and an A-site metal source according to a stoichiometric ratio, carrying out wet ball milling with ethanol, drying, and calcining in air at 900 DEG C for 15 hours. Through a multi-element doping strategy, the sodium ion diffusion dynamics, the electrochemical environment and the structural stability of the material are effectively improved, the rate capability, the cycle life and the air stability of the positive electrode material are remarkably improved, and the positive electrode material is suitable for the field of high-power sodium ion batteries.

The invention discloses a layered oxide positive electrode material of a sodium-ion battery and a preparation method of the layered oxide positive electrode material, and belongs to the technical field of batteries. The method comprises the following steps: preparing a NaNi < 0.33 > Mn < 0.33 > Fe < 0.33 > O2 precursor, mixing the precursor with a Na2S and P2S5 mixture under argon, carrying out heat treatment at 500 DEG C, and sintering with sodium hydroxide in an oxygen atmosphere at 800 DEG C to obtain the material. The core of the material is that a continuous super-ion conductor phase is formed on a grain boundary, a three-dimensional ion transmission network and a mechanical strengthening framework are constructed, the ion diffusion efficiency and the structural stability are remarkably improved, high-rate and long-cycle performance breakthrough is achieved, the process is controllable, and the industrialization potential is large.

The present disclosure provides a layered oxide cathode material and a preparation method thereof, a cathode sheet, and a sodium ion battery, and belongs to the technical field of sodium ion batteries. The layered oxide cathode material includes an O3@P2-phase composite oxide particle and an inert coating layer coated on its surface, and the O3@P2-phase composite oxide particle includes an O3-phase nickel-manganese-based oxide layered particle and a P2-phase metal oxide coating layer coated on the surface of the O3-phase nickel-manganese-based oxide layered particle; and the inert coating layer is a carbon layer and / or an inorganic metal oxide layer. When the layered oxide cathode material provided by the present disclosure is applied to the sodium ion battery, the prepared sodium ion battery has high initial coulombic efficiency, excellent rate performance, long cycle life, and good air stability.

The invention discloses a method for improving the air stability of a layered oxide positive electrode material of a sodium-ion battery, and belongs to the technical field of positive electrode materials of sodium-ion batteries. The method for improving the air stability of the layered oxide positive electrode material of the sodium-ion battery comprises the following steps: firstly, forming a weakly alkaline environment on the surface of the layered oxide positive electrode material of the sodium-ion battery, then sequentially carrying out acid leaching treatment and sintering, and forming a sodium metaphosphate coating layer on the surface of the layered oxide positive electrode material of the sodium-ion battery, the surface of the sodium-ion battery layered oxide positive electrode material is coated with sodium metaphosphate. A reagent used in the acid leaching treatment is a mixed solution of phosphoric acid and absolute ethyl alcohol. The capacity fading degree of the positive electrode material treated by the method is greatly reduced after the positive electrode material is exposed in air for 10 days, and good stability and electrochemical performance can be kept in the circulation process. The method is simple and convenient to operate and suitable for large-scale production, and an effective solution is provided for practical application of the layered oxide positive electrode material of the sodium-ion battery.

The present invention relates to a layered oxide cathode material, a method for producing the same, a cathode plate, and a sodium-ion battery, and belongs to the technical field of sodium-ion batteries. The layered oxide cathode material comprises O3@P2 phase composite oxide particles, which include O3 phase nickel-manganese oxide layered particles and a P2 phase metal oxide coating layer coated on the surface of the O3 phase nickel-manganese oxide layered particles, and an inert coating layer coated on the surface thereof, wherein the inert coating layer is a carbon layer and / or an inorganic metal oxide layer. When the layered oxide cathode material according to the present invention is used in a sodium-ion battery, the manufactured sodium-ion battery has high initial Coulomb efficiency, excellent rate characteristics, long cycle life, and good air stability.

The invention discloses an oxide cathode which comprises a cathode substrate and a cathode salt layer coated on the cathode substrate, the cathode salt layer comprises aluminum oxide, the cathode substrate comprises a nickel cathode cylinder, when the aluminum oxide in the cathode salt layer is pre-oxidized, nickel and the aluminum oxide can generate interface reaction to generate NiAl2O4, the interface stress can be obviously reduced, and the performance of the nickel cathode cylinder is improved. In subsequent further processing, molten or semi-molten aluminum oxide particles and previously formed NiAl2O4 can form chemical bonds, such as Ni-O-Al and Al-O-Al bonds, so that the adhesive force is remarkably improved, and small particles of aluminum oxide can also form a firm porous net-shaped framework on the cathode salt layer, so that other components in the cathode salt layer are firmly fixed, and the adhesive force is improved; the aluminum oxide is added in the cathode salt layer, so that the adhesive force between the cathode salt layer and the nickel cathode cylinder can be remarkably improved, the service life is prolonged, the aluminum oxide can improve the overall heat conductivity of the cathode salt layer, surface heat can be quickly conducted back to the nickel cathode cylinder, and the temperature during use is reduced.

The invention relates to a reversible oxygen ion conductor ceramic fuel cell and a preparation method thereof. The preparation method comprises the following steps: providing a Ni-YSZ / YSZ half cell; coating the surface of an electrolyte layer of the half cell with the GDC slurry through a wet spraying process; coating the Yb-doped CaMnO3 perovskite type oxide cathode slurry on the surface of a GDC layer of a half cell through a screen printing process; standing, drying and calcining to obtain a cathode; and carrying out electrode sintering and electrochemical activation treatment to obtain the reversible oxygen ion conductor ceramic fuel cell. The fuel cell cathode is prepared from the cobalt-free strontium-free Yb-doped CaMnO3 perovskite material, so that the problems that the thermal expansion matching property of a traditional cathode is poor, and a high-resistance phase is easily generated on an interface are effectively solved; in cooperation with a casting-co-sintering integrated preparation process, compact forming and tight combination of functional layers of the fuel cell are realized, and interlayer interface compatibility and structural stability are optimized.

The invention belongs to the technical field of sodium ion batteries, and particularly relates to an efficient sodium formate composite positive electrode sodium supplementing agent and preparation and application thereof. According to the preparation method, firstly, iron cluster catalyst particles are prepared through high-temperature calcination, then sodium formate grows on the surface of the catalyst in situ through an anti-solvent crystallization method, the composite sodium supplementing material is formed, and the composite structure can synchronously achieve reduction of the decomposition potential of sodium formate and improvement of the decomposition efficiency. Meanwhile, after the composite sodium-supplementing material is coupled with a layered oxide positive electrode, an efficient positive electrode sodium-supplementing effect can be played, active sodium loss caused by formation of a hard carbon negative electrode SEI film is made up, the first effect and the cycle performance of the battery are improved, and nearly 100% decomposition efficiency can be achieved. The molecular catalytic coupling size control effect is originally created, the sodium supplementing performance of sodium formate is remarkably improved, after the sodium formate is applied to a layered oxide positive electrode hard carbon negative electrode battery system, the first effect and the cycle performance of a battery are effectively improved, and good commercial application prospects are achieved.

The invention belongs to the field of sodium-ion battery positive electrode materials, and particularly relates to a sodium-ion battery layered oxide positive electrode material and a preparation method thereof. The invention discloses a sodium electric layered oxide positive electrode material, the chemical expression is Na < x > (M < 1y > M < 21-y-z > M < 3z >) O < 2 >, the element M < 1 > is an element with the basic valence being bivalent, the element M < 2 > is an element with the basic valence being trivalent, and the element M < 3 > is an element with the basic valence being tetravalent; wherein 0.87 < = x < = 0.95, 0.2 < = y < = 0.5, and 0.4 < = z < = 0.65; the sodium-electrode layered oxide positive electrode material has sodium vacancies, and the molar ratio of the sodium vacancies in the sodium-electrode layered oxide positive electrode material is greater than 0. According to the invention, sodium vacancies are introduced on the premise that the basic valence state of elements is balanced, so that sodium ions can be directly diffused through adjacent octahedral vacancies in the charging and discharging process, and the problem of poor cycling stability in the charging and discharging process of the sodium ion battery is avoided.

The invention discloses a P2-type sodium-manganese-based oxide positive electrode material suitable for electrochemical sodium pre-treatment as well as a preparation method and application thereof, and belongs to the technical field of sodium ion batteries. The general formula of the material before electrochemical sodium pre-treatment is P2-Na < x > Mn < 1-y > M < y > O < z >, and M is a doping element and is selected from one or more of Mg, Ni, Co, Fe, Cu, Zn, Al, Ti and Zr; 0.4 < = x < = 0.65, 0.05 < = y < = 0.5, and 2.0 < = z < = 2.2. It is found that the sodium content (x) and the doping amount (y) before sodium pre-treatment are controlled within the specific range, the obtained material can serve as an ideal sodium pre-treatment substrate, and the first-time charging specific capacity is remarkably improved to 180 mAh / g or above after electrochemical sodium pre-treatment. The general formula defines a novel high-performance positive electrode material, and a universal material solution is provided for the breakthrough of the energy density of the sodium-ion battery.

The invention relates to the technical field of batteries, in particular to a method for electrochemically recycling a waste metal oxide positive electrode and application of the method. The electrolytic tank is composed of a cathode (a waste metal oxide anode), an anode (a carbon material, a high-conductivity inert material and the like), an electrolyte (alkali metal chloroaluminate molten salt, ionic liquid and the like) and an oxide additive (lithium oxide, calcium oxide and the like). Through a one-step electrolysis process, the waste metal oxide positive electrode material is reduced and decomposed to form a transition metal salt and a lithium salt. And then the transition metal salt and the lithium salt are easily separated through simple water leaching post-treatment. According to the method for electrochemically recycling the waste metal oxide positive electrode, decomposition of the waste metal oxide positive electrode is achieved through energy of reduction electrons, the adopted electrolyte, electrode materials and the like are low-cost materials, compared with a traditional method, about 20% of energy consumption and greenhouse gas emission can be reduced, and in addition, the profit can be increased by nearly 10 times.

The invention provides a copper-containing layered oxide positive electrode material for a sodium-ion battery as well as a preparation method and application of the copper-containing layered oxide positive electrode material. The copper-containing sodium ion battery layered oxide positive electrode material comprises a nickel-iron-manganese-based sodium ion oxide positive electrode material and Cu, Zr and Ca doped in the nickel-iron-manganese-based sodium ion oxide positive electrode material. According to the invention, Cu, Zr and Ca are doped in the nickel-iron-manganese-based sodium ion oxide positive electrode material at the same time, the sodium ion layered oxide positive electrode material with single crystal morphology is obtained through the synergistic effect of doping the three elements into a nickel-iron-manganese system, and the specific discharge capacity of the positive electrode material under a relatively high voltage is remarkably improved; and the cycling stability and the rate capability are also improved.

A method of producing a particulate lithium metal oxide cathode material comprising the steps of providing an organic acid, providing a lithium compound, and providing a metal compound. The organic acid, the lithium compound, and the metal compound are mixed to form a mixture. The organic acid is melted to form a liquid organic acid, if the organic acid is provided as a solid. The mixture, including the liquid organic acid, is calcined in an atmosphere containing oxygen to form a lithium metal oxide. The lithium metal oxide is cooled and sized to produce the particulate lithium metal oxide having a predetermined average particle size.

The invention discloses a sodium ion battery composite positive electrode material and a short-time sintering synthesis method thereof.The method comprises the steps that a raw material precursor of a phosphoric acid pyrophosphoric acid polyanion compound is evenly and stably combined to the surfaces of layered oxide particles through a bridging agent, and short-time sintering is conducted after rapid heating is conducted in the argon atmosphere; a phosphoric acid pyrophosphate polyanion compound is effectively and stably grown or adhered to the surface of a layered oxide. Movement of the raw materials between a high-temperature area in the tubular furnace and a normal-temperature area outside the tubular furnace is utilized, synchronous and rapid heating of all parts inside and outside the raw materials to the sintering temperature is promoted, rapid and uniform generation of the material synthesis reaction is promoted, and after short-time sintering, the layered oxide structure and performance are maintained, and meanwhile the material yield is increased. The structure stability of the phosphoric acid pyrophosphate polyanion compound is utilized to improve the cycle stability of the layered oxide positive electrode material, and the composite positive electrode material with high energy density and high cycle stability is synthesized.

The present application relates to a kind of polymer solid electrolyte and its preparation method and application.The preparation raw material of the polymer solid electrolyte includes the following components: monofunctional monomer, polyfunctional monomer, sodium salt, initiator, plasticizer and fluoroethylene carbonate.The in-situ polymerized acrylate solid electrolyte provided by the present application has good interface compatibility with high-capacity layered oxide cathode, can effectively inhibit the side reaction of cathode / electrolyte interface, guarantee the efficient and stable transmission of sodium ion under high pressure, and help to improve its electrochemical performance in solid-state sodium battery.

This invention discloses a phosphate-modified sodium-ion battery cathode material and its preparation method. The preparation method includes the following steps: mixing the sodium-ion battery layered oxide cathode material with a phosphate precursor and subjecting it to heat treatment. The phosphate precursor reacts in situ with residual alkali on the cathode surface, effectively reducing the residual alkali content on the material surface and generating a sodium metaphosphate (NaPO3) coating layer with sodium ion conductivity. This coating layer effectively isolates the electrolyte, suppresses side reactions, and significantly improves the cycle stability of the material. Simultaneously, it increases the initial exothermic temperature of the cathode material in the electrolyte system and reduces the exothermic intensity, thereby achieving a synergistic improvement in electrochemical performance and thermal stability.

The invention discloses a method for improving the stability of a layered oxide positive electrode material. The method comprises the following steps: S1, matching a layered oxide positive electrode with a lithium-containing negative electrode to assemble a lithium ion battery; and S2, circulating the battery in a low-potential window to a voltage platform, and converting the battery into a slope curve. And S3, transferring the battery to a wide potential interval for circulation. The layered oxide positive electrode material has the over-lithiation phase change characteristic from LiMO2 to Li2MO2 during overdischarge, after the positive electrode is subjected to an electrochemical stabilization process in a voltage window containing over-lithiation phase change voltage, over-lithiation phase change does not occur in subsequent wide potential circulation, and the positive electrode can exert high capacity of 250-500 mAh g <-1 > through the electrochemical lithiation method, so that the positive electrode can be applied to the lithium ion battery. And wide-potential stable circulation can be realized.

Some embodiments are directed to systems and methods for direct recycling of batteries. In one aspect, a method includes obtaining spent cathode materials from spent batteries. The method includes wet milling the spent cathode materials in an aqueous medium to obtain deagglomerated particles. The method includes spray drying the deagglomerated particles to obtain a plurality of clusters of particles. The method further includes annealing the plurality of clusters of particles in a gaseous environment to obtain a plurality of single particles.