217 results about "Potassium-ion battery" patented technology

The invention provides an imine covalent organic polymer and a preparation method thereof, a negative electrode material and a potassium ion battery. The preparation method comprises the following steps: carrying out first mixing on raw materials including a carbonyl-containing first organic compound, an amino-containing second organic compound and a dispersion liquid to obtain a mixed liquid; carrying out in-situ polymerization reaction on the mixed solution to obtain an imine covalent organic polymer; wherein the first organic compound is nitro-substituted or non-substituted pyrene-4, 5, 9, 10-tetraketone; the second organic compound is selected from any one or more of C6-C12 aromatic amine compounds, C6-C12 heteroaromatic amine compounds and amino-substituted C4-C6 cyclic compounds, and the number of amino groups in each molecule of the second organic compound is greater than or equal to 2. The covalent organic polymer obtained by the preparation method can solve the problem that the structure is easily stacked and is easily dissolved in electrolyte to be damaged when the covalent organic polymer is used as a negative electrode material.

The invention relates to a method for preparing a hard carbon material from carbon dot heterogeneous cross-linked bituminous coal, a coal-based hard carbon material and application. The preparation method comprises the following steps: (1) soaking pretreated bituminous coal in an acid solution, washing to be neutral, and drying to obtain dry pulverized coal; (2) dispersing the carbon dots in an alcohol solvent for ultrasonic treatment to obtain a dispersion liquid; (3) mixing the dried pulverized coal obtained in the step (1) and the dispersion liquid obtained in the step (2), mechanically stirring, and drying to obtain a mixture; (4) performing low-temperature heating crosslinking on the mixture obtained in the step (3) in an oxygen-containing atmosphere so as to obtain a heterogeneous crosslinking product; and (5) performing high-temperature carbonization on the heterogeneous cross-linked product in an inert atmosphere to obtain the coal-based hard carbon material. The coal-based hard carbon material can be used as a sodium ion battery / potassium ion battery negative electrode, and has excellent sodium / potassium storage performance.

The invention discloses a high-entropy positive electrode material of a potassium ion battery and a preparation method and application of the high-entropy positive electrode material, the high-entropy positive electrode material is a layered oxide with a P2 / rock salt biphase symbiotic structure, the chemical general formula of the high-entropy positive electrode material is K < 0.6 > Mn < 0.75-x > Ni < 0.1 > Ti < 0.1 > Mg < x > Cu < 0.05 > O2, and x is more than 0 and less than or equal to 0.1. A high-temperature solid-phase method is adopted in the preparation process, the high-entropy layered oxide positive electrode material with symbiotic two phase structures of P2 and rock salt is finally formed by regulating and controlling the types and the content of doped elements, sliding of a TM layer in the charging process and large structural stress generated in the circulating process are relieved through introduction of a small amount of rock salt phase, and the performance of the positive electrode material is improved. And lattice distortion and cracks in particles in the long circulation process are improved, so that the electrochemical circulation stability and rate capability of the potassium ion battery are remarkably improved.

The invention discloses a preparation method and application of a manganese fluoride / carbon nanofiber composite material. The method comprises the following steps: dissolving metal salt and a fluorine-containing high polymer material in an organic solvent to obtain a precursor solution; performing electrostatic spinning on the precursor solution to obtain nanofibers, and drying to remove the solvent; and calcining the nanofiber in an inert atmosphere, and fluorinating and carbonizing at the same time. The method disclosed by the invention is simple in process, the manganese fluoride / carbon nanofiber composite materials with different particle sizes can be prepared by adjusting the concentration of a manganese source and the pyrolysis temperature, and the prepared material has excellent electrochemical performance and is a promising negative electrode material for the potassium ion battery.

The invention discloses a porous carbon negative electrode material for a potassium ion battery and a preparation method and application thereof, and the preparation method comprises the following steps: (1) mixing and grinding glucose and MgO or CaO to obtain a uniform raw material; (2) putting the raw materials into a corundum boat, and carrying out high-temperature calcination in a protective atmosphere to obtain pyrolyzed powder; and (3) mixing and stirring the pyrolyzed powder and hydrochloric acid, and performing suction filtration and drying to obtain the porous carbon negative electrode material of the potassium ion battery. The porous carbon negative electrode material provided by the invention has rich mesoporous and macroporous structures, shows excellent potassium storage performance, has high specific capacity, excellent rate capability and long cycle stability, and is suitable for large-scale energy storage application.

The invention relates to a potassium ion battery cathode material preparation method, which comprises: S1, mixing a vanadium source, a phosphorus source and citric acid, drying, and calcining for the first time to obtain a mixture precursor; and S2, mixing the mixture precursor obtained in the step S1 with a potassium source, and calcining for the second time to obtain the cathode material. The potassium ion battery cathode material beta-KVOPO4 prepared by the invention has excellent structural stability and relatively high working voltage, shows good cycle stability, can be matched with various anode materials to prepare a potassium ion secondary battery with high energy density, and has far-reaching significance in application of the potassium ion battery cathode material.

The invention discloses a tellurium-doped sulfurized polyacrylonitrile potassium storage negative electrode material and a potassium ion total battery, and belongs to the field of potassium ion batteries. In order to solve the technical problems of low sulfur utilization rate and poor rate capability when sulfurized polyacrylonitrile is used as a potassium storage negative electrode material, the tellurium-doped sulfurized polyacrylonitrile (Te-SPAN) material with high performance is synthesized in a tellurium doping manner. In the tellurium-doped sulfurized polyacrylonitrile (Te-SPAN), the content of tellurium is lower than 5%, the content of sulfur is 33%-39%, and the content of carbon is 59%-62%. When the Te-SPAN is used as a potassium storage negative electrode material, the Te-SPAN shows high potassium storage capacity, excellent rate capability and cycling stability. In addition, the potassium ion total battery assembled based on the composite negative electrode and the low-defect manganese potassium hexacyanoferrate positive electrode also shows very excellent electrochemical performance.

The invention discloses a low-disordered expanded pi conjugated organic material, a preparation method thereof and a potassium ion battery. The preparation method comprises the following steps: by taking commercial tetraaminobenzoquinone as a synthetic monomer, adding a hydrochloric acid solution for ultrasonic dispersion, then adding sodium acetate to obtain a turbid solution II, then placing the turbid solution II in flowing oxygen, heating and stirring, then washing and drying, putting the obtained powder into dimethyl sulfoxide to obtain a turbid solution III, then ventilating and drying at high temperature, then washing with ethanol, and filtering to obtain a target product. And drying in vacuum to obtain the low-disordered expanded pi conjugated organic material. The organic material can expose more active sites and has a more open skeleton structure, potassium ion diffusion paths are reduced, the capacity and rate capability of TAPT can be greatly improved, the problem that the capacity, cycling stability and ionic conductivity are difficult to improve at the same time when the organic electrode material is applied to a potassium ion battery is solved, and the application prospect is wide. The preparation method is high in cost benefit, simple, convenient and environment-friendly in preparation process, wide in application range and excellent in electrochemical performance.

The invention discloses a potassium ion battery positive electrode material and a preparation method and application thereof, the chemical general formula of the positive electrode material is Kw [MnxFeyCuzMgaZrbAlc] O2, in the formula, 0.40 < = w < = 0.50, 0.75 < = x < = 0.85, 0.02 < = y < = 0.06, 0.02 < = z < = 0.06, 0.02 < = a < = 0.06, 0.02 < = b < = 0.06, and 0.02 < = c < = 0.06; x + y + z + a + b + c = 1.

The invention discloses a modified hard carbon material, a preparation method thereof and a battery, and relates to the technical field of battery negative electrode materials. The preparation method comprises the following steps: forming a hard carbon layer by taking grafted silicon dioxide as a template, coating the hard carbon layer with a soft carbon layer, coating the soft carbon layer with silicon dioxide, performing confinement carbonization, and removing the template. Wherein the grafted silicon dioxide contains hetero atoms S, and the hard carbon layer contains hetero atoms P. During preparation, a silicon dioxide template grafted with 3-mercaptopropyltriethoxysilane is prepared by a reverse micelle method, a phenolic resin precursor is coated to form the hard carbon layer, P is introduced through modification of triglycidyl phosphate, then an asphalt-based soft carbon layer is coated, and carbonization is performed to obtain the modified phenolic resin. And removing silicon dioxide to obtain the target material. According to the material, active sites and interlayer spacing are increased through precise doping of S and P, volume expansion is relieved through cooperation of soft carbon and hard carbon, ion adsorption is enhanced through oxygen groups, and the material shows high capacity and excellent cycle stability in secondary batteries such as potassium ions and the like and is suitable for the field of novel energy storage batteries.

The present invention relates to the synthesis of pure metal or multi-metal derivatives of ZIF-11, ZIF-12 or amorphous ZIF structures in high yield followed by calcination under inert conditions to produce in composite nanostructures one or more metal selenide dispersed on the surface of or embedded in a carbon matrix, and using these composites as electrodes for lithium ion batteries, sodium ion batteries, potassium ion batteries, supercapacitors or fuel cells.

The invention provides a double-phase layered potassium ion battery positive electrode material and a preparation method and application thereof, the chemical general formula of the potassium ion battery positive electrode material is Kx (Mn0. 25Fe0. 25) 1-yCryO2, x is more than or equal to 0.3 and less than or equal to 0.5, and y is more than or equal to 0.85 and less than or equal to 0.95; the positive electrode material of the potassium ion battery has a P3 / O3 double-phase layered structure; the preparation method comprises the following steps: (1) weighing a potassium source, a manganese source, an iron source and a chromium source according to a molar ratio of K: Mn: Fe: Cr = 1.05 x: 0.25 (1-y): 0.25 (1-y): y, and carrying out ball milling to obtain precursor powder; (2) carrying out tabletting treatment on the precursor powder, and putting a pressed sheet into a porcelain boat; (3) calcining the porcelain boat in a muffle furnace; by adjusting the potassium content and regulating the doping of the transition metal, the prepared double-phase layered positive electrode material for the potassium ion battery has the advantages of high capacity and high stability.

The present invention relates to the technical field of battery materials, and in particular to a nitrogen-sulfur co-doped hard carbon negative electrode material for sodium / potassium ion batteries and a preparation method thereof. The preparation method comprises preparing a mixture powder of dodecyl sulfonate and a nitrogen source, carbonizing under inert gas conditions, washing the carbonized product, and vacuum drying to obtain a nitrogen-sulfur co-doped hard carbon negative electrode material. The introduction of nitrogen atoms in the negative electrode material prepared by the present invention can change the surface charge distribution of the carbon material, improve the electronic conductivity, and at the same time increase the active sites, and promote the capacitive adsorption behavior of the carbon material for sodium / potassium ions; the introduction of sulfur atoms can increase the hard carbon interlayer spacing, reduce the sodium / potassium ion diffusion energy barrier, enhance the diffusion kinetics behavior, and synergistically improve the sodium / potassium storage performance of the hard carbon material. The above-mentioned negative electrode material can be used to prepare sodium / potassium ion batteries with high specific capacity, excellent rate performance and long cycle stability, and the preparation method is simple in process, controllable in large quantities, low in cost, and environmentally friendly.

The invention provides a layered-perovskite biphase potassium ion battery positive electrode material as well as a preparation method and application thereof, and belongs to the field of new energy materials. The preparation method of the material comprises the following steps: S1, weighing a proper amount of a potassium source, a manganese source and a praseodymium (or lanthanum and gadolinium) source in a ball milling tank; s2, ethanol is added for ball milling treatment, and a mixture is obtained; s3, drying the mixture; s4, the obtained dried product is subjected to heat treatment, the heat treatment temperature is 850-900 DEG C, the heat treatment time is 12-15 h, then the dried product is cooled to the room temperature, and a black product is obtained; and S5, grinding, sieving and drying the obtained product to obtain the positive electrode material of the potassium ion battery. According to the preparation method, a special sintering atmosphere is not needed, the layered-perovskite double-phase positive electrode material can be obtained only through one-time calcination, and the prepared positive electrode material has better circulation and rate performance compared with a layered single-phase positive electrode material.

The invention provides a microwave plasma preparation method and application of a manganese-based potassium ion battery positive electrode material, and the method comprises the following steps: S1, dissolving a dispersant in deionized water and ethanol to obtain a mixed solvent; s2, ball-milling and mixing a potassium source, a manganese source and other transition metal sources in the solvent to form uniform slurry; and S3, putting the precursor prepared by spray drying into a microwave plasma sintering furnace, and quickly heating and calcining to obtain the manganese-based potassium ion battery positive electrode material. Spray drying is adopted to remove a solvent, the morphology is controlled, and solvent residues are avoided; calcining is rapidly completed through a microwave plasma technology, the sintering time is shortened to the minute level, the productivity is improved, and the energy consumption is reduced; ball milling, spray drying and microwave plasma sintering are easy to increase the yield, and a new path is provided for large-scale production.

The invention belongs to the field of organic electrolytes and potassium ion batteries, and particularly relates to a low-concentration ionic liquid electrolyte for breaking the concentration balance of potassium ions and anions and a high-energy-density potassium ion battery. The potassium ion battery comprises a Prussian blue (PB) positive electrode, an electrolyte and a commercial ferrocene (Fc) negative electrode which is not subjected to any treatment, and the electrolyte is a low-concentration ionic liquid electrolyte (FSI-: K + (3.5 / 0.3 M)) of potassium bis (fluorosulfonyl) imide (KFSI). The low-concentration ionic liquid electrolyte developed by the invention has a high anion: K < + > concentration ratio (3.5: 0.3 M), increases the solvation proportion of rich anions, reduces the dissolution of an Fc organic metal compound, and ensures high interface stability and rapid K < + > storage kinetics of an Fc negative electrode. Meanwhile, the electrochemical window of the low-concentration electrolyte is widened, the PB positive electrode can stably circulate at 1.0-4.4 V, the long-period circulation and excellent rate capability of the PBFc total battery are also realized, and the total battery has the energy density of 246.7 Wh / kg under the current density of 20 mA / g.

A unique frame for rocking chair type sodium and potassium ion batteries is disclosed. In the case of a sodium ion battery, a battery includes a first electrode operably assembled as an anode of the battery, and includes a sodium ion source. The battery includes a second electrode operably assembled as a cathode of the battery, and includes at least one polymeric binder, an electrically conductive carbon-based material, and an active material. The battery further includes an electrolyte disposed between the first electrode and the second electrode, the electrolyte supporting electrochemical transport of sodium ions. The active material comprises a binary compound, and the binary compound comprises a polyaniline polymer and a graphene-based material. The first electrode, the second electrode, and the electrolyte are operably assembled to function as a rocking chair type sodium ion battery.

The application discloses a modified hard carbon material and a preparation method and a battery thereof, and relates to the technical field of battery negative materials. The hard carbon layer is formed by using grafted silica as a template, then the soft carbon layer is coated outside the hard carbon layer, and then the silica is coated outside the soft carbon layer to limit carbonization and remove the template to obtain the target material; wherein the grafted silica contains a heteroatom S, and the hard carbon layer contains a heteroatom P; in the preparation, the silica template grafted with 3-mercaptopropyl triethoxysilane is prepared by a reverse micelle method, the phenol formaldehyde resin precursor is coated to form the hard carbon layer, P is introduced by modification of the trisglycidyl phosphate, and then the pitch-based soft carbon layer is carbonized, and then the silica is removed to obtain the target material. The material increases the active sites and the interlayer spacing by accurate doping of S and P, cooperatively relieves the volume expansion by the hard and soft carbons, and strengthens the ion adsorption by the oxygen groups, and exhibits high capacity and excellent cycle stability in the secondary batteries such as potassium ion batteries, and is suitable for the field of new energy storage batteries.

The invention belongs to the technical field of battery positive electrode material preparation, and particularly relates to a cross-linked conjugated polymer, a preparation method and application in an alkali metal battery. When the cross-linked conjugated polymer is used as a positive electrode, the cross-linked conjugated polymer shows excellent performance in lithium, sodium and potassium ion batteries: the average discharge voltage is as high as 3.4-3.5 V, which is beneficial for improving the energy density of the battery; under extremely high current density, high capacity exceeding 120mAh. G <-1 > can still be released, and extremely fast dynamic characteristics are shown; and under the harsh test condition, the capacity retention ratio still reaches up to 85%-90%.

The application discloses a flower ball-shaped bismuth disulfide / tungsten disulfide composite material and a preparation method and application thereof. Tungsten hexachloride is added into anhydrous ethanol solution and fully stirred, then bismuth nitrate pentahydrate is added into the mixed solution and stirred to uniformly disperse the bismuth nitrate pentahydrate into the solution, then thioacetamide is added and stirred to be uniform, the obtained solution is moved into a reaction kettle, and the reaction kettle is sealed and placed into a homogeneous reactor; after the reaction is completed, the product is taken out, washed and fully dried in a vacuum oven to obtain the composite material. The composite material has a thickness of 20-30 nm, and nanosheets are vertically grown on a self-assembled flower ball-shaped structure with a diameter of 350-400 nm; the composite material can be applied to preparation of a potassium ion battery negative electrode material, and the structure is more stable, the conductivity is better, and the electrochemical performance is greatly improved.

The invention discloses a bismuth-antimony-tin alloy negative electrode material of a potassium ion battery and a preparation method of the bismuth-antimony-tin alloy negative electrode material, and belongs to the technical field of new energy. The preparation method comprises the following steps: firstly, obtaining bismuth-antimony-tin alloy precursor powder by adopting an oil bath evaporation drying method, then putting the bismuth-antimony-tin alloy precursor powder into a tubular furnace, carrying out heat treatment under a protective atmosphere, and washing and drying to obtain the bismuth-antimony-tin-carbon composite material. The middle entropy property of the ternary alloy enables the structural stability of the material to be improved, three-dimensional carbon coating can relieve volume expansion of alloy particles in the circulation process, and the circulation stability of the composite material is improved.

The application relates to a high-conductivity double-carbazole type two-dimensional conductive metal organic framework material, a preparation method and application thereof, and belongs to the field of metal organic framework materials. Three double-carbazole type two-dimensional conductive metal organic framework materials Cu-DCA-MOF, Cu-DCPy-MOF and Cu-DCPt-MOF are prepared, all of which have a special "rotor-stator" structure, and are obtained by coordination polymerization of double-carbazole type ligands and metal ions. Due to the special "rotor-stator" structure of the double-carbazole type ligands, the three materials have high crystallinity and high conductivity, and have important significance in enriching the types and structural diversity of two-dimensional conductive metal organic framework materials. In addition, the double-carbazole type two-dimensional conductive metal organic framework materials with high conductivity can be applied in potassium ion batteries, and provide a new idea and solution for the development of positive electrode materials of the potassium ion batteries.

The invention relates to an in-situ polymerization cross-linked battery adhesive as well as a preparation method and application thereof, and belongs to the technical field of electrode materials. The technical problems that a traditional linear adhesive is low in mechanical strength, poor in high-temperature stability and prone to swelling in electrolyte, and an existing crosslinking technology is complex in process and incompatible with an existing production line are solved. The invention provides an adhesive. A polyamino compound and polyethylene glycol with multiple epoxy end groups are spontaneously subjected to a ring-opening polymerization reaction through amino groups and epoxy groups, and a three-dimensional cross-linked polyether-amine network structure is formed in situ. The method is simple in process and compatible with a conventional electrode drying process. A cross-linked network formed by the adhesive endows the electrode with excellent mechanical strength and stripping resistance, and active substances can be effectively inhibited from falling off; and meanwhile, the high thermal stability and the insolubility in electrolyte are realized, so that the cycle life and the safety of lithium ion, sodium ion and potassium ion batteries are remarkably prolonged, and the safety of the lithium ion, sodium ion and potassium ion batteries is remarkably improved.

The invention discloses a pomegranate-shaped core-shell structure tin pyrophosphate negative electrode material as well as a preparation method and application thereof, and belongs to the technical field of electrochemical energy storage materials. The preparation method comprises the following steps: mixing tetravalent tin salt and a phosphonic acid organic ligand, and carrying out hydrothermal reaction to obtain a tin-based metal organic framework precursor; the phosphonic acid organic ligand is selected from one or two of phenylphosphonic acid or (pyridine-2-yl methyl) phosphonic acid; and carrying out heat treatment on the tin-based metal organic framework precursor at 550-700 DEG C to obtain the pomegranate-shaped core-shell structure tin pyrophosphate negative electrode material. The tetravalent tin salt and the specific phosphonic acid ligand are used for constructing the precursor, and the Kirkendall effect in the pyrolysis process is utilized to form a unique core-shell structure, so that the negative electrode material shows excellent cycling stability under high current density when being used for the potassium ion battery or the sodium ion battery.

Provided is a cathode active material for a rechargeable alkali metal battery, wherein the cathode active material comprises a sodium salt composite comprising a mixture or composite of Fe and at least a sodium salt selected from NaxA, wherein x is from 1 to 3, and the anion Ax− is selected from F−, Cl−, Br−, I−1, PO43−, SO42−, CO32−, SiO32−, NO3−, B4O72−, or a combination thereof, wherein a molar ratio of Fe-to-sodium salt is from 1 / 9 to 9 / 1. Also provided is a rechargeable alkali metal battery comprising this cathode active material, which is a sodium battery (sodium-ion or sodium metal battery), a lithium battery (lithium-ion or lithium metal battery), or a potassium battery (potassium-ion or potassium metal battery).

The invention relates to the technical field of energy storage, in particular to a boron-doped porous composite carbon nanosheet as well as a preparation method and application of the boron-doped porous composite carbon nanosheet. Rape seed cakes and coal pitch are used as carbon sources, boric acid is used as a boron source, and zinc acetate is used as a template and catalyst; the preparation method comprises the following steps: uniformly mixing rape seed cakes, coal pitch, boric acid and zinc acetate, putting the mixture into a carbonization furnace, and heating in an argon atmosphere to prepare the boron-doped porous composite carbon nanosheet. The specific surface area of the porous composite carbon nanosheet is between 288 and 544 m < 2 > / g; the total pore volume ranges from 0.37 cm < 3 > / g to 0.54 cm < 3 > / g; as a negative electrode material of a potassium ion battery, in a 1.0 M potassium bis (fluorosulfonyl) imide (KFSI) electrolyte, when the current density is 0.1 C, the specific capacity can reach 308.9 mAh / g; and when the current density is 5C, the capacity is kept at 114.5 mAh / g after circulation is carried out for 1 to 200 times. When the current density is increased to 20C, the specific capacity can reach 95.4 mAh / g, and high capacity and good rate capability are shown.

The application discloses a novel Na2MnFe(CN)6 material and application thereof as a lithium ion battery, a sodium ion battery, a potassium ion battery, a magnesium ion battery, a zinc ion battery and a zinc-sodium dual-ion battery positive electrode material, wherein the Na2MnFe(CN)6 material is an inorganic material. The excellent electrochemical performance of the novel Na2MnFe(CN)6 material in the application indicates that the novel Na2MnFe(CN)6 material has a very large application prospect as the lithium ion battery, the sodium ion battery, the magnesium ion battery, the zinc ion battery and the zinc-sodium dual-ion battery positive electrode material. Meanwhile, the novel Na2MnFe(CN)6 material has a simple and controllable preparation process, and a simple device, and is a method easy to mass produce.

The invention relates to the technical field of energy storage, in particular to a sulfur-doped interconnected hollow porous composite carbon nano-microsphere, a preparation method and application of the sulfur-doped interconnected hollow porous composite carbon nano-microsphere. According to the invention, resorcinol-formaldehyde resin and coal pitch are used as carbon sources, and sublimed sulfur is used as a sulfur source; the preparation method comprises the following steps: uniformly mixing resorcinol-formaldehyde resin, coal pitch and sublimed sulfur, putting the mixture into a carbonization furnace, and heating in an argon atmosphere to prepare the sulfur-doped interconnected hollow porous composite carbon nano-microspheres. The specific surface area of the hollow porous composite carbon nanospheres is 230-390 m < 2 > / g; the total pore volume is between 0.16 cm < 3 > / g and 0.38 cm < 3 > / g; as a negative electrode material of a potassium ion battery, in a 1.0 M potassium bis (fluorosulfonyl) imide (KFSI) electrolyte, when the current density is 0.1 C, the specific capacity reaches 394.6 mAh / g; and when the current density is 5C, the capacity is kept at 200.6 mAh / g after circulation is carried out for 1 to 500 times. When the current density is increased to 20C, the specific capacity can reach 140.4 mAh / g, and high capacity and good rate capability are shown.

The invention discloses a sodium manganate positive electrode material with an interlayer stacking structure as well as a preparation method and application of the sodium manganate positive electrode material. The sodium manganate positive electrode material has an ABB 'C' ABB 'C' type oxygen layer stacking sequence, Mg < 2 + > ions specifically occupy twisted triangular prism sites in an alkali metal sodium layer, and P type and O type NaO6 coordination polyhedrons exist in a crystal structure of the material at the same time. Through a composite three-step synthesis process of'sol-gel-solvothermal-solid phase method ', the thermodynamic tendency that conventional magnesium ions occupy a transition metal layer is effectively broken, and synergistic distortion of prismatic interstitial sites is realized, so that a brand new symmetric structure different from a traditional P phase and a traditional O phase is constructed. According to the positive electrode material disclosed by the invention, unfavorable phase transformation in the charging and discharging process is remarkably relieved through a special lattice stacking structure, the positive electrode material has high capacity and long cycle life, and a new thought is provided for the design of a high-energy-density sodium or potassium ion battery.

This invention discloses a SnS / WS2@C composite electrode material, its preparation method, and its application, belonging to the field of tungsten disulfide nanomaterials technology. A precursor solution A is obtained by uniformly dispersing SnCl2·2H2O and CH3CSNH2 in anhydrous ethanol. After a solvothermal reaction, precursor solution A is cooled, centrifuged, washed, and freeze-dried to obtain powder B. Powder B, WCl6, and CH3CSNH2 are uniformly dispersed in anhydrous ethanol to obtain solution C. After a solvothermal reaction, solution C is cooled, centrifuged, washed, and freeze-dried to obtain powder D. Powder D is uniformly dispersed with glucose in deionized water to obtain precursor solution E. After a solvothermal reaction, precursor solution E is cooled, centrifuged, washed, and freeze-dried to obtain powder F. Powder F is calcined at high temperature to obtain the SnS / WS2@C composite electrode material. Performance testing of the prepared SnS / WS2@C composite electrode material revealed that it exhibits good electrochemical performance when used as a negative electrode in potassium-ion batteries.