Shanghai Research Institute of Petrochemical Technology, Sinopec

China Petroleum Chemical Corporation

China Petroleum & Chemical Corporation

Sai Sun

Huanxin Gao

Siyu Zhang

Wenqian Dong

A silicon-based negative electrode material, a preparation method therefor, and an application thereof in a lithium ion battery are provided. A lithium ion battery contains the silicon-based negative electrode material. The negative electrode material contains a silicon-containing material and a phosphorus-containing coating layer at the surface of the silicon-containing material. The phosphorus-containing coating layer contains a polymer that has polycyclic aromatic hydrocarbon structural segments. The negative electrode material exhibits improved initial coulombic efficiency, reversible charging specific capacity, cycle charging capacity retention and conductivity. When used in the lithium ion battery, the negative electrode material may improve the energy density of the battery.

Negative electrode material, preparation method therefor, and application thereof, and lithium ion battery comprising same

A negative electrode material of the lithium-ion battery, a preparation method therefor and an application thereof, and a lithium-ion battery include the same are provided. The negative electrode material has a core-shell structure. The core has a silicon-containing material while the shell has an organic lithium salt and a porous carbon film, and at least part of lithium ion is intercalated in the porous carbon film. The negative electrode material is prepared by (1) mixing a silicon source and a carbon source, and then calcining the mixture; (2) mixing the calcined product obtained in the step (1) with the organic lithium salt; and (3) subjecting the materials obtained in the step (2) of mixing to vacuum freeze-drying.

Negative electrode material, preparation method therefor and application thereof, and lithium-ion battery

A graphene powder, its preparation method and application are provided. The graphene powder is a stack of graphene sheets. The graphene powder involves in its Raman spectrum a D peak and a G peak with peak heights of Iand Irespectively, where I/Iis 0.10 or less. The graphene powder can be applied in conductive composite materials, anti-corrosion coatings, heat dissipation composite materials. In particular, when used in lithium-ion batteries, it can significantly reduce electrode internal resistance and improve battery stability at any current rates.

Graphene powder, and preparation method therefor and application thereof

A conductive composite material of graphene contains graphene nano-sheets and conjugated copolymers. The conjugated copolymers has alkynyl groups and are in a linear structure and grafted to the graphene nano-sheets. The preparation of conductive composite material includes the steps of: pretreating the graphene nano-sheets with 4-bromobenzenediazonium tetrafluoroborate, and forming the conjugated copolymers in the presence of the pretreated graphene nano-sheets. The conductive composite material of graphene can be uniformly dispersed in an electrode slurry, reduce the internal resistance of an electrode, and improve the electrical conductivity of an electrode. At the same time, the flexible structure associated with the graphene nano-sheets can buffer the volume expansion of the silicon-containing negative materials during charge-discharge cycling. Such a composite material can be in a lithium-ion battery.

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Shanghai, China

Sai Sun