3results about How to "Improve battery cycle performance" patented technology

A lithium secondary battery includes: a positive electrode; a negative electrode; a separator provided between the positive and negative electrodes; and an electrolyte. The positive electrode includes a positive electrode current collector and a positive electrode active material provided on the positive electrode current collector. The negative electrode includes a negative electrode current collector and a negative electrode active material layer provided on the negative electrode current collector. The positive electrode active material layer includes a positive electrode active material including a lithium composite transition metal compound which includes nickel, cobalt and manganese, where the nickel is in an amount from 80 mol% to 100 mol% among the metals except for lithium and is in the form of a single particle. The negative electrode active material layer includes a Si / C-based active material in an amount from 3 parts to 100 parts by weight of the entire negative electrode active material.

The invention belongs to the field of lithium ion batteries, and discloses a high-temperature thermal response curing electrolyte and a preparation method and application thereof.The electrolyte comprises a carbonic ester organic solvent, a lithium salt, a polymer monomer, a thermal response initiator and an accelerant, and the polymer monomer has a benzene ring and at least two glycidyl ether functional groups. An organic matter with a benzene ring and at least two glycidyl ether functional groups is adopted as a polymer monomer, the problem that an acrylate chain segment of an acrylate system is prone to fracture at high temperature is solved, the heat stability after curing is improved, the rigidity of a polymer and the insulativity after curing are improved, and the service life of the polymer is prolonged. The condition that ion transmission cannot be completely blocked after polyethylene glycol diglycidyl ether and the like are cured can be prevented, and the problems that an existing thermal response electrolyte is low in initiation temperature, insufficient in insulativity after being cured and poor in thermal stability are solved.

The application relates to the technical field of sodium ion batteries, in particular to a preparation method and application of a high-entropy doped iron-based selenide material. The preparation method of the iron-based selenide is as follows: iron powder, selenium powder and multiple doped powders are subjected to ball milling treatment, and then calcination treatment is carried out to obtain the high-entropy doped iron-based selenide material. The iron-based selenide is endowed with excellent conductivity through high-entropy doping, the rate performance of the iron-based selenide material as a battery negative electrode is increased, and a large number of lattice defects can be introduced through high-entropy doping, so that the stability of the structure of the iron-based selenide material is improved, meanwhile, the preparation method has the characteristics of high selenium powder utilization rate, solvent-free and short time consumption. When the high-entropy doped iron-based selenide material prepared by the application is used as a sodium ion battery negative electrode material, the electrode pulverization and deactivation caused by the volume expansion of the metal selenide electrode material during the charging and discharging process can be effectively relieved, so that the sodium ion battery has better battery cycle performance.