369results about How to "Improve Coulombic efficiency" patented technology

The invention provides an efficient and controllable sodium ion battery hard carbon negative electrode chemical sodium pre-treatment method, which comprises the following steps: in an inert atmosphere, dropwise adding an aryl-sodium organic solution on the surface of a hard carbon negative electrode plate, and washing and drying the plate after the aryl-sodium organic solution permeates the hard carbon negative electrode plate. The aryl-sodium solvent is 9-methyl fluorene-sodium, 9, 9-dimethyl fluorene-sodium and derivative sodium thereof. Through hard carbon negative electrode pre-sodium treatment, the loss of active sodium in the first-circle charging and discharging process of the negative electrode is compensated, and the first-circle coulombic efficiency of the negative electrode is improved. The method is simple and convenient to operate, the sodium modification degree of the hard carbon negative electrode is controllable, the reaction safety is high, and large-scale research is easy to realize industrial production. The sodium ion total battery is assembled by matching the pre-sodium hard carbon negative electrode and the sodium vanadium fluorophosphate positive electrode, the initial discharge specific capacity of the total battery is greatly improved, the energy density of the sodium ion battery is favorably improved, and the sodium ion total battery has wide prospects and application value.

The invention provides an Al-Mg alloy negative electrode current collector, a preparation method thereof and a negative-electrode-free sodium metal battery, and relates to the field of batteries. The preparation method of the Al-Mg alloy negative electrode current collector comprises the following steps: sputtering magnesium on the surface of an aluminum foil by adopting a magnetron sputtering mode, and forming a magnesium coating on the aluminum foil; and calcining the aluminum foil with the magnesium plating layer to obtain the Al-Mg alloy negative electrode current collector, and the Al-Mg alloy negative electrode current collector comprises an aluminum substrate layer and an Al-Mg alloy layer located on the aluminum substrate layer. According to the present invention, the Al-Mg alloy with characteristics of high sodium affinity and stable three-dimensional structure is introduced into the negative electrode current collector so as to induce the uniform deposition of sodium, inhibit the growth of sodium dendrites, reduce the loss of active sodium, and prolong the cycle life of the battery; the negative electrode current collector can be used in a sodium metal battery without a negative electrode. In addition, the method has the advantages of being easy to operate and low in raw material cost, and large-scale application and popularization are facilitated.

The invention discloses a composite three-dimensional current collector prepared based on chemical plating, a metal negative electrode and a metal secondary battery, and belongs to the technical field of metal secondary batteries. The composite three-dimensional current collector comprises a nonmetal three-dimensional skeleton matrix and a metal coating which is uniformly distributed on the surface of the matrix through chemical plating. When the metal battery works, Mg, Li, Na, Ca, Zn and other metals are induced to be subjected to uniform electro-deposition and stripping on the surface of the composite three-dimensional current collector by virtue of affinity among metals, and the three-dimensional porous structure of the matrix provides a buffer space for metal deposition, so that metal ions are subjected to rapid and uniform electro-deposition; the stability of an electrode interface can be enhanced, dendritic crystal growth is reduced, the electrodeposition overpotential of metal is reduced, and the service life of a metal negative electrode is prolonged. The composite three-dimensional current collector prepared on the basis of chemical plating solves the problem of non-uniform growth of a metal negative electrode, and is an effective way for commercialized production of a metal secondary battery.

The invention relates to the technical field of solid electrolyte, and discloses a double-layer solid electrolyte membrane, a preparation method thereof and an all-solid-state battery. The double-layer solid-state electrolyte membrane comprises a first solid-state electrolyte layer and a second solid-state electrolyte layer which are overlapped with each other, the first solid-state electrolyte layer comprises hydride solid-state electrolyte, and the second solid-state electrolyte layer comprises halide solid-state electrolyte; the hydride solid electrolyte comprises Li < 7-a > P (BH4) S < 6-a > and / or Li < 7-a-b > P (BH4) S < 6-a-b > X , a < = 2, 0lt; blt; 2. The interface between the double-layer solid-state electrolyte membrane and the positive electrode and the interface between the double-layer solid-state electrolyte membrane and the negative electrode have good interface stability, and the interface side reaction between the two solid-state electrolyte layers is less, so that the solid-state battery has high coulombic efficiency and cycling stability.

The invention discloses a preparation method of a biomass hard carbon negative electrode material with low specific surface area, which comprises the following steps: S1, pretreating a biomass raw material to obtain a carbon precursor; s2, carbonizing the carbon precursor at low temperature; s3, crushing and processing low-temperature carbides; s4, preparing a pickling solution for pickling; s5, fine grinding after acid pickling; s6, fusion: fusing a product obtained after fine grinding with asphalt to form a carbon precursor; s7, performing air oxidation modification to obtain an oxidized carbon precursor; s8, carrying out high-temperature carbonization treatment on the oxidized carbon precursor; S9, scattering and dissociating; s10, screening is carried out; and preparing the sodium-ion battery hard carbon negative electrode material. The surface of the biomass carbon material is coated with asphalt, macropores or mesopores on the surface are filled and coated with the asphalt, and then a hard carbon structure is formed through air oxidation and high-temperature carbonization, so that the specific surface area and the first charge-discharge irreversible capacity of the material are reduced, and the coulombic efficiency and the specific capacity are improved.

The invention provides an ionic liquid additive for a solid-state lithium metal battery electrolyte and a method for preparing the solid-state lithium metal battery electrolyte by using the ionic liquid additive. The bistrifluoromethanesulfonyl imide salt containing terphenyl and lithium carboxylate obtained through Michael addition reaction is captured by open metal sites of the MOF material UiO-66-NH2, the structural stability of the material can be improved, more transmission channels are provided for lithium ions, and therefore the transference number of the lithium ions is increased, the performance of the lithium metal battery is improved, and the service life of the lithium metal battery is prolonged. Especially in the aspect of charge and discharge rate. The electrolyte material disclosed by the invention has good stability with lithium metal, so that electrolyte decomposition can be prevented, and an unstable phenomenon, such as lithium dendrite growth, on the surface of an electrode can be avoided, so that a lithium metal battery can show excellent electrochemical performance, including better cycling stability, high coulombic efficiency and longer battery life.

The invention belongs to the technical field of negative-electrode-free sodium metal batteries, and particularly discloses a negative-electrode-free sodium battery modified current collector and a preparation method and application thereof.The preparation method includes the steps that on the basis of polypyrrole preparation, transition metal salt is added, and the nitrogen doping type in polypyrrole-derived nitrogen-doped nano carbon particles is regulated and controlled. The negative-electrode-free sodium battery modified current collector prepared by the preparation method disclosed by the invention is high in relative content of N-6 and N-5 type doped nitrogen, so that the sodium affinity of a nitrogen-doped coating is improved, the nucleation over-point location of sodium metal is reduced, the reversibility of a sodium deposition / stripping reaction is improved, and the electrochemical performance of a negative-electrode-free sodium battery is further improved.

The invention provides a silicon carbon material with a multilayer coating structure and a preparation method and application thereof, and relates to the technical field of battery materials. The silicon-carbon material with the multi-layer coating structure comprises a porous carbon core body, and a first carbon layer and a second carbon layer which sequentially coat the porous carbon core body from inside to outside, and the porous carbon core body comprises porous carbon and nano silicon particles deposited on the surface and in pore channels of the porous carbon; and a conductive nano carbon filler is dispersed in the second carbon layer. The silicon carbon material with the multilayer coating structure provided by the invention is used as a lithium ion battery negative electrode material, and has excellent specific capacity, coulombic efficiency and cycle performance. The result of the embodiment shows that when the silicon carbon material with the multi-layer coating structure is applied to the lithium ion battery, the first reversible capacity is 1882-2071 mAh / g, the first coulombic efficiency is 92.6-94.1%, and the capacity retention ratio of 100 cycles is 95.3-97.7%.

The invention provides a method for cyclically regenerating a positive electrode active material by using magnesium sulfate, which comprises the following steps: 1) burdening and mixing waste lithium battery black powder, magnesium sulfate and a carbon source, and roasting the mixture in a vacuum or inert atmosphere to obtain a roasted product; (2) adding the roasted product into water to carry out water leaching treatment, and carrying out suction filtration to obtain a lithium sulfate solution and water leaching residues; 3) adding the lithium sulfate solution into the saturated sodium carbonate solution for lithium precipitation to obtain a lithium carbonate precipitate; (4) drying the water leaching residues, adding dilute sulphuric acid to carry out acid leaching treatment, filtering to obtain acid leaching residues and a magnesium sulfate solution, and then carrying out evaporative crystallization treatment on the magnesium sulfate solution to obtain a magnesium sulfate precipitate; 5) mixing the acid leaching residues with lithium carbonate, and sintering to obtain the regenerated ternary positive electrode active material.According to the method, the recovery rate of obtained lithium reaches 99% or above, loss of important elements in the regeneration process can be avoided, cyclic utilization of magnesium sulfate is achieved, and consumption of chemical reagents and secondary pollution are reduced.

The embodiment of the invention provides a positive pole piece, a battery monomer, a battery and an electric device. The positive pole piece comprises a positive current collector and a positive film layer arranged on at least one side of the positive current collector; the positive electrode film layer comprises a positive electrode active material, a sodium supplementing agent and a first conductive agent; wherein the specific surface area of the first conductive agent is not less than 600m < 2 > / g. According to the technical scheme, the coulombic efficiency and the cycle performance of the battery can be improved.

The invention relates to the technical field of batteries, in particular to a composite electrolyte, a lithium metal battery and application of the lithium metal battery. The invention relates to a composite electrolyte which comprises a fluorinated cyclic ether solvent, an alkane solvent, LiPF6 and LiTFSI, the carbon atom number Ra of the fluorinated cyclic ether solvent skeleton is more than or equal to 3 and less than or equal to 6; the volume ratio A of the fluorinated cyclic ether solvent is greater than or equal to 50% and smaller than or equal to Alt; 100%; the volume ratio B of the alkane solvent meets 0 lt; b < = 50%; the structural tortuosity Rb of the hydrocarbon solvent satisfies 1.5 < Rb < = 3; the ratio of the molar concentration Rc of LiPF6 to the molar concentration Rd of LiTFSI is more than 0 and less than or equal to 1. The composite electrolyte provided by the invention has excellent comprehensive physical and chemical properties, especially low-temperature performance, and can improve the cycle performance and rate capability of the battery.

The invention provides a low-molar-concentration I < + > stabilizer / zinc salt aqueous zinc-iodine battery electrolyte and an aqueous zinc-iodine battery, and belongs to the technical field of aqueous zinc-iodine battery electrolytes.The electrolyte comprises the following chemical components: an I < + > stabilizer, other zinc salts, a multi-iodide ion complexing agent, a diluent and water; in the electrolyte, the concentration of the I + stabilizer is 0.5-1.5 mol / L, the concentration of the other zinc salt is 0.5-2.5 mol / L, the mass fraction of the multi-iodide ion complexing agent is 3-15%, and the volume ratio of the diluent to the water is 1: (3-19); the multi-iodide ion complexing agent comprises at least one of polyvinyl alcohol, polyethylene glycol and polyvinylpyrrolidone. The electrolyte can still realize high coulombic efficiency of the aqueous zinc-iodine battery in the presence of a low-molar-concentration I < + > stabilizer / zinc salt, and also can inhibit side reaction at one end of a zinc negative electrode in the cyclic process of the aqueous zinc-iodine battery, shuttle effect of multi-iodide ions in the I- / I2 conversion process at one end of an iodine positive electrode and hydrolysis of I < + > in the I2 / I < + > process, so that the cycle life of the battery is prolonged, and the service life of the battery is prolonged. And the working temperature range is widened, so that the device can stably operate under severe conditions.

The invention belongs to the field of secondary batteries, and particularly relates to an aqueous zinc ion battery electrolyte additive and an electrolyte. The additive is a beta-diketone organic reagent. When the additive is added into the zinc salt-containing electrolyte, dendritic crystal growth and hydrogen evolution corrosion of zinc can be remarkably inhibited, so that the cycle performance and coulombic efficiency of the zinc ion battery are improved. According to the invention, the zinc ion battery has good cycle performance, is easy for industrial production, and has an application prospect in the technical field of energy storage.

The invention provides a solid electrolyte for a lithium battery and a preparation method and application thereof, and belongs to the technical field of solid electrolytes.The solid electrolyte is prepared from, by mass, 40-75 parts of lithium salt, 10-30 parts of cross-linking agent, 5-25 parts of nanoscale silicon borate glass fiber and 1-10 parts of photoinitiator. The lithium salt, the cross-linking agent, the nanoscale silicon borate glass fiber and the photoinitiator are adopted as raw materials, a polymer component formed after ultraviolet curing has high mechanical performance, a stable electrolyte-electrode interface can be formed, growth of lithium dendrites can be effectively inhibited, the risk of short circuit of the battery is reduced, and the service life of the battery is prolonged. Therefore, the overall safety of the battery is improved, and the service life of the battery is prolonged. As an inorganic filler, the nanoscale silicon borate glass fiber is beneficial to reducing the crystallinity of a polymer component and increasing an amorphous phase region, so that rapid migration of lithium ions is facilitated, and the ionic conductivity and coulombic efficiency of the battery are improved.

The invention discloses a PEO-based solid electrolyte film and a preparation method and application thereof, the PEO-based solid electrolyte film comprises a polymer matrix and a lithium salt, the polymer matrix is selected from PEO, and the lithium salt is selected from LiTFSI; the PEO-based solid electrolyte film also comprises a molecular coordination regulator and a filler, the molecular coordination regulator is selected from DFBOP, and the filler is selected from LLZTO. According to the PEO-based solid electrolyte film disclosed by the invention, the problems of poor lithium stability and high-voltage compatibility of PEO-based solid electrolyte can be remarkably improved, and the cycling stability and rate capability of a PEO-based solid lithium metal battery can be remarkably improved.

The invention discloses a heterostructure composite material and a preparation method thereof, and a preparation method and application of a composite material positive electrode, the preparation method of the composite material comprises the following steps: sequentially adding a solvent, vanadium pentoxide and a conductive polymer monomer into ball milling equipment for ball milling to obtain conductive polymer intercalated vanadium pentoxide; 2, adding the conductive polymer intercalated vanadium pentoxide obtained in the step 1 into a solvent, uniformly mixing, and sequentially adding a silver nitrate solution and a reducing agent to obtain a composite material with a heterostructure formed by the Ag nanocrystal modified conductive polymer intercalated vanadium pentoxide; according to the manufacturing method of the aqueous zinc ion battery positive electrode, the process is simple, the cost is low, the yield is high, the repeatability is good, the zinc ion battery positive electrode material with good rate / cycle performance and high coulombic efficiency is obtained, and the prepared product is excellent in performance through an electrochemical performance test.

The invention relates to the field of new energy storage materials, and discloses a multifunctional composite perfluorosulfonic acid ion exchange membrane for an all-vanadium redox flow battery, and the composite membrane comprises the following components: perfluorosulfonic acid resin which accounts for 60-90wt% of the total mass of the membrane and is used as a matrix material; the functionalized multi-walled carbon nanotube accounts for 5-15 wt.% of the total mass of the membrane, and carboxyl and hydroxyl are introduced through surface treatment; phosphotungstic acid accounts for 5-20wt.% of the total mass of the membrane, and is anchored on the surface of the functionalized multi-walled carbon nanotube through an electrostatic spinning process; n, N-dimethylformamide and isopropanol are used as solvents, and the solvents are mixed with a perfluorinated sulfonic acid resin solution according to the volume ratio of 1: 1. The proton conductivity, the vanadium ion barrier property and the tensile strength of the composite membrane are obviously superior to those of a traditional Nafion membrane. According to the technical scheme, an efficient and economical solution is provided for improving the overall performance of the all-vanadium redox flow battery, and the method has good application prospects and market value.

The invention discloses a method for modeling an all-vanadium redox flow battery and improving the coulombic efficiency of the battery, aiming at the composition and principle of VRB, a circuit model comprising electrochemistry, fluid mechanics, temperature, bypass current and vanadium battery multi-stack equivalent loss is established, and the influence of pumping loss and bypass current in an all-vanadium redox flow battery pipeline system on the vanadium battery is explored. By establishing the relation between the pumping loss and the pumping loss current, a bypass current model and a multi-stack series vanadium battery equivalent loss circuit model, all the models are converted into a whole, the kernel mechanism of the vanadium battery considering the dynamic response is elaborated, and the dynamic response of the vanadium battery is analyzed according to key factors involved in modeling research of the VRB, including the pumping loss and the bypass current. And how the factors comprehensively influence the performance and the efficiency of the battery is elaborated, and an idea is provided for pipeline design and improvement of the energy efficiency of the battery for manufacturers.

The invention relates to the technical field of batteries, in particular to a diaphragm for a battery, a preparation method of the diaphragm and an aqueous sodium-ion battery. The battery diaphragm comprises a diaphragm substrate and a coating arranged on the diaphragm substrate, wherein the coating comprises carbon-coated sodium ferrocyanide, a conductive agent and a binder. The preparation method of the battery diaphragm comprises the following steps: mixing the carbon-coated sodium ferrocyanide, the conductive agent, the binder and the solvent to prepare slurry, coating the slurry on the diaphragm substrate, and drying to obtain the battery diaphragm. The high-performance battery diaphragm is obtained by arranging the modified coating containing the carbon-coated sodium ferrocyanide, the conductive agent and the binder on the conventional diaphragm substrate, and the diaphragm can improve the long cycle stability, the capacity, the coulombic efficiency and the energy density of the battery when being used for the water-based sodium ion battery.

The invention provides a negative electrode material, a preparation method thereof and a lithium ion battery, and relates to the technical field of lithium ion batteries. The negative electrode material comprises a silicon-based material core and a coating layer formed on at least part of the surface of the silicon-based material core, wherein the coating layer has a pore structure; the differential pore structure ratio delta phi of the negative electrode material meets # imgabs0 #, wherein delta S is the area of a hysteresis loop in an isothermal adsorption and desorption curve of the negative electrode material; s is the specific surface area of the negative electrode material; delta P is the interval difference value of the relative pressure P / P0 corresponding to the hysteresis loop; qmax is the maximum isothermal adsorption capacity of the negative electrode material. The preparation method of the negative electrode material comprises the step of carrying out CVD (Chemical Vapor Deposition) treatment on a to-be-coated silicon-based material core to obtain the negative electrode material of which the coating layer has a pore structure. The coating layer with a special pore structure is arranged on the negative electrode material, so that the rate capability and the cycle performance of the material are improved.

The invention discloses zinc ion battery electrolyte as well as a preparation method and application thereof, and belongs to the technical field of ion battery electrolyte. According to the preparation method disclosed by the invention, the coumarin derivative is added into the basic zinc salt solution, so that the uniform deposition of zinc ions can be promoted at a low temperature of-20 DEG C or below, the formation of dendritic crystals is remarkably reduced, and a stable protective layer is formed on the surface of the zinc anode, and the protective layer can maintain high reversibility of the battery at a normal temperature, and also can be used for preparing a lithium ion battery. And the stability can be kept in a low-temperature environment, so that the battery can show excellent electrochemical performance under different temperature conditions, and the technical problem of the electrochemical performance of the water-based zinc ion battery (ZIBs) in the low-temperature environment is solved.

The invention provides a preparation process of a composite current collector, the composite current collector and a negative-electrode-free sodium metal battery. The preparation process of the composite current collector comprises the following steps: mixing aromatic diamine, an acrylate monomer and a polyester polymer, adding an initiator, adding a graphene solution, and mixing to obtain a polymer solution; carrying out hydrothermal reaction on the polymer solution to obtain three-dimensional porous flowable gel; and compounding the three-dimensional porous flowable gel on a current collector to obtain the composite current collector. According to the preparation process disclosed by the invention, a polymer obtained by polymerizing aromatic diamine and acrylate monomers under the action of an initiator and a hydrothermal reaction is used as a transverse and longitudinal skeleton, a polyester polymer is used as an interlayer cross-linking agent, and graphene is used as a lamellar skeleton, so that three-dimensional porous flowable gel can be compounded on the current collector; the three-dimensional porous flowable gel can improve the gram volume exertion and cycle performance of the negative-electrode-free sodium metal battery.

The invention discloses an organic carbonyl compound electrode material, a preparation method and application of the organic carbonyl compound electrode material in a lithium ion battery, and the organic carbonyl compound electrode material is bipyridino [3 ', 2': 5, 6; the invention relates to an organic carbonyl compound electrode material, which is prepared from 2, 2 ', 3': 7, 8] quinoxaline [2, 3-i] bipyridino [3, 2-a: 2 ', 3'-c] phenazine-10, 21-diquinone and 1, 2, 4, 5-tetraamino p-benzoquinone and 1, 10-phenanthroline-5, 6-diketone through a dehydration condensation reaction. When the organic electrode material is used as a positive electrode material to be applied to a lithium ion battery, due to the fact that the organic electrode material contains a large conjugated system, the organic electrode material has good dissolution inertness in electrolyte and is beneficial to electron transmission, and therefore the cycling stability and the rate performance of the battery are improved. In addition, multiple active sites provide more redox active sites to coordinate with lithium ions, so that reversible lithium storage is realized, and relatively high capacity is shown.

The invention belongs to the technical field of flow battery energy storage, and more specifically relates to a near-neutral total iron flow battery negative electrode electrolyte and a preparation method thereof, the negative electrode electrolyte is prepared from an iron salt, a chelating agent, a stabilizing agent, a supporting electrolyte and water at a certain temperature, the total iron concentration is 0.1-1.0 M, the molar ratio of the chelating agent to the iron salt is 1.2-2.0, the molar ratio of the stabilizing agent to the supporting electrolyte is 1.2-2.0, and the total iron concentration is 0.1-1.0 M. The molar ratio of the stabilizer to Fe is 0.25-1.0, the supporting electrolyte concentration is 0-2.0 mol / L, and the pH value is 7.0-8.5. The near-neutral negative electrode electrolyte for the total-iron flow battery is high in stability, can effectively inhibit generation of ferric hydroxide precipitates under a neutral condition, improves the stability of iron ions, greatly prolongs the cycle life of the total-iron flow battery, and can be widely applied to various aqueous flow batteries.

The invention provides a cross-linked polybenzimidazole membrane as well as a preparation method and application thereof. The cross-linked polybenzimidazole membrane comprises a cross-linked network structure, main raw materials of the crosslinked polybenzimidazole membrane comprise polybenzimidazole, a crosslinking agent and a pore forming agent, the crosslinking agent is a diepoxy compound or a silane coupling agent with an epoxy bond, and the addition amount of the crosslinking agent relative to the polybenzimidazole is 2wt%-10wt%. The cross-linked polybenzimidazole membrane is high in mechanical strength, good in mechanical stability, low in swelling rate in electrolyte and high in durability; the cross-linking agent and the pore-forming agent selected in the invention can ensure that the cross-linked polybenzimidazole membrane forms a cross-linked network structure.

The present application discloses a method for preparing a carbon material for a battery, comprising: filtering and concentrating papermaking black liquor to obtain liquid lignin; polymerization: adding a cross-linking agent to the liquid lignin for cross-linking and curing reaction to obtain a lignin polymer solid; pre-oxidation: pre-oxidizing the lignin polymer solid to obtain a lignin-based resin; pre-carbonization: pre-carbonizing the lignin-based resin in a non-oxidizing gas atmosphere to obtain a carbon material precursor 1; gas phase deashing: gas phase deashing the carbon material precursor 1 in a non-oxidizing gas atmosphere under the action of a halogen compound and / or a halogen element to obtain a carbon material precursor 2; calcination: crushing the carbon material precursor 2 and calcining it in a protective atmosphere to obtain a carbon material for a battery. The method of the present application effectively improves the expansion and foaming phenomenon during lignin carbonization, and the obtained carbon material has low ash content, controllable specific surface area, and excellent electrochemical performance. A lignin-based resin as mentioned above is also disclosed.

The invention belongs to the technical field of electrochemical batteries, and particularly relates to an aqueous electrolyte capable of being used for a high-rate tin metal negative electrode and a tin-manganese battery. The aqueous electrolyte comprises an acidic solvent, a tin salt and various high-valence metal salts / charged water-soluble polymers, and can also comprise a manganese salt. According to the method, high-valence metal salt / charged water-soluble polymer is added into the aqueous electrolyte, the repulsive force of double electric layers is adjusted by using introduced charged particles, and the distribution of an electric field and a concentration field at an interface is homogenized, so that efficient ion transmission and uniform and compact tin deposition behaviors are realized. Meanwhile, the charged particles can effectively inhibit related side reactions on the manganese positive electrode side, so that the tin metal negative electrode and the tin-manganese battery can have long cycle life and excellent rate capability at the same time. In addition, the water-based electrolyte is low in raw material price and small in dosage, the reaction process is simple and mild, and the water-based electrolyte has good application and development prospects.

The invention discloses a silicon monoxide-based negative electrode material and preparation and application thereof, and belongs to the technical field of lithium ion battery preparation, and the preparation method comprises the following steps: bombarding pure silicon monoxide powder by nitrous oxide plasma to form N-attached modified porous silicon monoxide powder; more lithium ions can be accommodated for intercalation and deintercalation due to the porosity, the volume effect of the material in the electrochemical reaction process can be relieved, so that the cycle life of the battery is prolonged, and meanwhile, the N element is doped in the generated carbon layer, so that the conductivity and the lithium storage capacity are improved; the two prepared coating layers form a compact carbon coating layer after high-temperature carbonization, the structural integrity of the silicon monoxide negative electrode material in the charging and discharging process is enhanced, the compact carbon coating layer can effectively relieve stress caused by volume change and reduce repeated generation and fracture of an SEI film in the embedding and de-embedding process of lithium ions, and the lithium ion battery has the advantages of being simple in preparation process, low in cost and high in reliability. The first coulombic efficiency is improved, and the capacity and performance stability of the battery can be maintained.

The invention belongs to the technical field of manufacturing of negative-electrode-free sodium / magnesium metal battery current collectors, and discloses a copper-based composite current collector, a preparation method thereof and application of the copper-based composite current collector in a negative-electrode-free metal battery. The current collector is used for solving the problem that the cycle life of a battery is short due to disordered deposition of sodium / magnesium ions and overgrowth of sodium / magnesium dendrites of a traditional current collector under high current density and high surface capacity. According to the invention, the linear copper sulfide with the thickness of about 0.05-1 mu m is constructed on the surface of the copper foil in situ through a liquid-phase vulcanization method, the thickness of the copper sulfide modification layer is 0.5-5 mu m, and the nucleation overpotential of sodium ions or magnesium ions on a current collector can be effectively reduced. When the material is applied to a sodium / magnesium metal battery without a negative electrode, high average coulombic efficiency and excellent cycle life of the battery under ultra-high current density surface capacity can be realized.

The invention relates to the technical field of lithium ion battery positive electrode materials, in particular to a composite phosphate positive electrode material and a preparation method and application thereof. The provided composite phosphate positive electrode material comprises a phosphate positive electrode material core and a carbon coating layer, the particle size of the composite phosphate positive electrode material is in normal distribution, the thickness of the carbon coating layer is 2.0-3.0 nm, and the variance is 0.01-0.30. The obtained finished product is relatively large in particle size and uniform in particle size, and the compaction density is remarkably improved; moreover, the surface of the core material is uniformly coated with the carbon coating layer, and the thickness of the carbon coating layer is moderate, so that not only can the electronic conductivity of the positive electrode material be improved, but also the discharge capacity, coulombic efficiency and other electrochemical properties of the composite phosphate positive electrode material can be improved.