6results about How to "Excellent long cycle performance" patented technology

The application discloses a kind of miscellaneous anion oxyhalide solid electrolyte and preparation method, application and full solid battery thereof;Belong to solid battery technical field.The electrolyte material chemical formula is Li （3d+2e+2f+g） M m+ b N n+ c (PO4) d (SO4) e (CO3) f (OH) g X (mb+nc) , M is alkaline earth metal, N is one or more of transition metal, rare earth metal and P area metal, X is at least one of F, Cl, Br and I.The twisted Li-X sublattice structure formed by introducing halogen atom of the material of the application significantly reduces lithium ion migration barrier, expands lithium ion transport channel through special angle sharing oxygen network structure, also endows material with excellent mechanical flexibility, and the halogen-rich passivation layer spontaneously formed on the surface of the material makes it show excellent environmental stability;Not only solve the key material bottleneck of solid battery development, more provide solid technical support for promoting new energy industry to higher safety, higher energy density direction development.

The invention specifically discloses an electrolyte and a lithium ion battery. The electrolyte comprises an electrolyte for first injection and an electrolyte for second injection, the first injection electrolyte comprises a first solvent, a first additive and a first lithium salt; the first solvent comprises dimethyl carbonate, the first additive comprises vinylene carbonate and a composite additive, and the composite additive comprises at least one of fluoroethylene carbonate, ethylene sulfate and methylene methanedisulphonate; the mass ratio of the dimethyl carbonate is 45%-50%; the secondary injection electrolyte comprises a second solvent, a second additive and a second lithium salt; the second solvent comprises dimethyl carbonate, and the second additive comprises vinylene carbonate; the mass ratio of the dimethyl carbonate is 45%-50%; the mass ratio of the vinylene carbonate is 15%. The lithium battery has the advantages of high energy density and long cycle performance.

This invention discloses a method for preparing a composite solid electrolyte membrane that inhibits interfacial reactions, comprising the following steps: dissolving a fluorinated polymer and a lithium salt in N,N-dimethylformamide and stirring at 45-55°C to obtain solution A; ball-milling a garnet solid electrolyte to obtain a uniform dispersion, adding bicarbonate and stirring to obtain solution B, wherein the mass ratio of fluorinated polymer, lithium salt, garnet solid electrolyte, and bicarbonate is 0.4:0.6:1:0.15-0.25; adding solution B to solution A and stirring to obtain a uniform electrolyte slurry, transferring it to a glass petri dish, drying it first at 45-50°C with forced air, and then vacuum drying it at 110-120°C to obtain the composite solid electrolyte membrane. This invention introduces bicarbonate to improve the alkaline environment of the garnet solid electrolyte, achieving quantitative control of the interfacial reaction between the fluorinated polymer and the garnet solid electrolyte, and increasing the ionic conductivity to 10. ‑3 S cm ‑1 .

The application provides a kind of sodium ion battery negative electrode material and its preparation method and application.The negative electrode material includes black phosphorus, carbon carrier and sodium salt;The morphology of the carbon carrier is the morphology of LDH template;The black phosphorus and sodium salt are compounded in the carbon carrier;The carbon carrier is also doped with double metal ions, and the double metal is the double metal element in the LDH template.The negative electrode material provided by the application has multiple bonding effects between the carbon carrier, phosphoric acid, double metal ions and sodium salt, which ensures the stability of the material interface and effectively inhibits the volume expansion of black phosphorus during the cycle process;And the interaction between each substance, synergistic effect, makes the negative electrode material have excellent cycle stability and high reversible capacity, and also has good rate performance.

The invention relates to the technical field of lithium ion batteries, and particularly discloses carbon-coated lithium iron phosphate and a preparation method thereof. Comprising the following steps: taking Prussian blue as a carbon source and an iron source, mixing a lithium source, a phosphorus source, Prussian blue and a dispersing agent in water, and performing ball milling to obtain a precursor; and calcining the precursor in a protective atmosphere to obtain the carbon-coated lithium iron phosphate. Prussian blue is used as an iron source and a carbon source at the same time, secondary sintering or additional carbon source adding is not needed, one-time sintering forming is achieved, the process is simple, and operation is easy. The carbon-coated lithium iron phosphate provided by the invention has excellent rate capability and long cycle performance, and can meet the requirements of high energy and high power output.

The invention discloses a gel polymer electrolyte based on a three-layer asymmetric gradient structure as well as a preparation method and application of the gel polymer electrolyte, and relates to the technical field of electrolyte materials of high-voltage lithium metal batteries. The gel polymer electrolyte comprises a three-layer structure of a cathode side layer, a middle layer and an anode side layer which are sequentially stacked, the three-layer structure takes polyvinylidene fluoride-hexafluoropropylene copolymer as a matrix and realizes functional partition through gradient doping of inorganic filler, and the inorganic filler is sodium niobate nanoparticles and gamma-Al2O3 particles; the components of each layer are accurately regulated and controlled, collaborative optimization of a lithium metal anode-electrolyte-high-voltage cathode interface and mechanical strength is realized, ohmic polarization and concentration polarization are reduced through a gradient structure, the ion transmission efficiency is improved, and the performance of the lithium ion battery is improved. The problems that an electrolyte in an existing high-voltage lithium metal battery is insufficient in electrode-electrolyte interface stability, poor in ion transport kinetics, weak in mechanical property, potential in safety hazard and the like are solved.