33results about How to "Improve initial Coulombic efficiency" patented technology

The present invention relates to a cathode active material for a lithium rechargeable battery, a method of manufacturing the same, and a lithium rechargeable battery including the same, and provides the cathode active material for the lithium rechargeable battery, including a core including a compound represented by the following Chemical Formula 1, and a coating layer positioned on the core and including a compound represented by the following Chemical Formula 2.xLi2MnO3—(1-x)LiM1O2  [Chemical Formula 1]In Chemical Formula 1, 0<x<1 and M1 is a transition metal.yMnOz—(1-y)LiM2O2  [Chemical Formula 2]In Chemical Formula 2, 0<y<1, 1≤z≤4, and M2 is a transition metal.

A multiple-element composite material for negative electrodes, a preparation method therefor, and a lithium-ion battery using the negative electrode material. The lithium-ion battery uses multiple-element composite material for negative electrodes has a core-shell structure containing multiple shell layers. The inner core consists of graphite and nano-active matter coating the surface of the graphite. The outer layers of the inner core are in order: the first shell layer is of an electrically conductive carbon material, the second shell layer is of a nano-active matter, and the third shell layer is an electrically conductive carbon material coating layer. The multiple-element composite material for negative electrodes of the present invention combines coating processing technology with surface composite modification and coating modification technology to successfully prepare a multiple-element composite material for negative electrodes having a core-shell structure containing multiple shell layers, and allows for high load and high dispersion for the nano-active matter, thereby substantially enhancing the material specific capacity, cycle performance, and initial efficiency. Additionally, the multiple-element composite material for negative electrodes of the present invention has high compacted density and good processing performance. The negative electrode material has simple preparation technique and low raw material cost, is environmentally friendly, and causes no pollution.

A composite anode active material includes a metal that may be alloyed with lithium, an intermetallic compound incapable of alloying with lithium, and a carbonaceous material, wherein the intermetallic compound exists in a phase structurally separated from the metal capable of alloying with lithium. Since the composite active material contains an intermetallic compound that does not form any alloy phase with lithium nor the metal capable of alloying with lithium but rather exists in a structurally separated phase, the composite active material exhibits excellent coulombic efficiency. Further, anode electrodes and lithium batteries including the composite anode active material exhibit improved charge and discharge characteristics.

Provided is an all-solid-state lithium rechargeable cell, comprising: a) a cathode, wherein the cathode comprises: a1) a composite of VS4 and graphene; and a2) a solid catholyte; and b) a lithium-based anode. In particular, the all-solid-state lithium rechargeable cell of the present disclosure may exhibit high initial discharge capacities, high initial Coulombic efficiencies, good reversible capacities, excellent cycling stabilities, high energy densities as well as outstanding safeties.

The invention discloses a method for supplementing lithium with negative electrode active materials of lithium ion batteries, belonging to the field of lithium ion batteries. The key to the lithium supplementation method is to add the negative electrode active material into the organic lithium solution in two stages to obtain the second-stage lithium supplementary active material, and then add the second-stage lithium supplementary active material to the organic compound solution for calcination and cleaning , to obtain a lithium supplement active material product. The present invention adopts a two-stage method to supplement lithium, which not only helps to form a dense and good SEI film on the surface of the active material, but also makes the lithium supplementing degree of the active material higher and achieves a higher initial Coulombic efficiency; Lithium supplementation significantly and effectively improves the initial Coulombic efficiency and electrochemical performance of the battery. The invention adopts an organic solution oxidation-reduction method to supplement lithium to the negative electrode active material, the process is mild, the amount of lithium supplementation is controllable, and the accuracy is high, which is suitable for existing equipment and is beneficial to industrial application.

The invention provides a modified silicon-carbon negative electrode material and its preparation method and application. The preparation method includes the following steps: (1) mixing the silicon-carbon negative electrode material and lithium alkoxide solution, and performing solvothermal reaction; (2) alcohol washing Step (1) The solid powder obtained after the solvothermal reaction is dried to obtain a modified silicon-carbon negative electrode material; the lithium alkoxide solution is formed by mixing metal lithium and an alcohol solvent. The preparation method provided by the invention has a simple process, and the pre-lithiation of the surface of the silicon-carbon negative electrode material can be realized through a simple solvothermal reaction, which reduces the irreversible capacity in the first charge and discharge process, and improves the first Coulombic efficiency to more than 92%.

A battery electrode is provided that includes a porous silicon microstructure precursor, a silicon shell coating deposited on the silicon microstructure precursor, and a graphene coating deposited on the silicon shell coating, where the graphene coating encapsulates the silicon shell coating forming a graphene-encapsulated silicon-shell-protected porous silicon microstructure precursor battery electrode.