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

The invention provides a lithium ion battery negative electrode active material. The lithium ion battery negative electrode active material is a compound CuGe<2+x>P3 with a structure shown in a formula (I), wherein 0<=X<=10. According to the invention, a Cu element with high conductivity and Ge with lithium reaction activity are subjected to ball milling by using a high-energy ball milling method;the CuGe2P3 material is synthesized by simultaneously introducing a P element into a sphalerite structure of a component, and Ge solid solution is carried out on the material by using a high-energy ball milling method, so that CuGe2 + XP3 series materials are successfully prepared, and the charge-discharge platform of the material is adjustable. The obtained series of materials have the advantages of high initial coulombic efficiency, high specific capacity, proper working potential and small charging and discharging platform difference.

The invention provides an antimony sulfide-based negative electrode material for a lithium ion battery and a preparation method of the antimony sulfide-based negative electrode material, and relates to the field of lithium ion battery negative electrode materials. According to the method, antimony trioxide, expanded graphite and sulfur powder are mechanically mixed at a high speed for a long timeby adopting a mechanical ball milling method to form a composite material, and the composite material is annealed and vulcanized in argon to obtain the antimony sulfide-based composite material with the sulfur-doped graphite packaged antimony sulfide structure. According to the invention, the sulfur-doped graphite material and the graphene stripped from the expanded graphite are compounded so as to increase the electronic conductivity of the antimony sulfide, and the packaging structure formed by the existence of the sulfur powder during the ball milling can easily relieve agglomeration of theantimony sulfide caused by the volume expansion; and the initial Coulombic efficiency, the reversibility of the conversion reaction, the cycling stability and the rate capability are greatly improvedthrough the combined action of the components. The mechanical ball milling method disclosed by the invention is simple and easy to operate and convenient for large-scale production.

A multiple-element composite material for negative electrodes, a preparation method therefor, and a lithium-ion battery using tile 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.

The present invention discloses a layered copper-containing oxide material and a preparation process and purpose thereof The material has a general chemical formula of Na_0.68+aNi_bCu_cM_dMn_eO_2+δ, where Ni, Cu, M, and Mn respectively form octahedral structures together with six oxygen atoms that are most adjacent therein, the octahedral structures have arrangements with common edges and constitute transition metal layers; alkali metal ions Na⁺ are located between every two of the transition metal layers; M is specifically one or more of Mg²⁺, Mn²⁺, Zn²⁺, Co²⁺, Al³⁺, B³⁺, Cr³⁺, Mn³⁺, Co³⁺, V³⁺, Zr⁴⁺, Ti⁴⁺, SiO⁴⁺, Mo⁴⁺, Ru⁴⁺, Nb⁴⁺, Sb⁵⁺, Nb⁵⁺, Mo⁶⁺, and Te⁶⁺; and a, b, c, d, e, δ, and m meet (0.68+a)+2(b+c)+md+4e=2(2+δ), and b+c+d+e=1.

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.

A lithium ion battery anode material, a method thereof and a lithium ion battery. The lithium ion battery anode material includes graphite carbon materials and functionalized graphene. The method of the lithium ion battery anode material includes the following steps: compounding a graphite phase carbon material and functionalized graphene by liquid phase compounding method or solid phase compounding method, to obtain a lithium ion battery composite material. The lithium ion battery anode material provided by the present invention has the advantages of high capacity, high initial coulombic efficiency, excellent cycle performance and low production cost.

The invention belongs to the technical field of lithium ion battery materials, and particularly relates to a polyphenol-modified zinc-iron-based heterojunction oxide carbon nano lithium ion battery negative electrode composite material as well as a preparation method and application thereof. The preparation method comprises the following steps: mixing and stirring an iron source, a zinc source and a carbon source, centrifuging, drying, and carrying out heat treatment to obtain a ZnFe2O4/ZnO/C negative electrode material. The negative electrode material provided by the invention solves the problems of poor cycle and rate performance, fast capacity fading, serious battery polarization, low charge and discharge coulombic efficiency and the like of the existing lithium ion battery negative electrode material. The ZnFe2O4/ZnO/C has excellent electrochemical properties such as good cycling stability, excellent rate capability, small battery overpotential polarization voltage and high charge and discharge coulombic efficiency when being used as a lithium ion battery negative electrode material.

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.

A carbon-based anode material with high ramp capacity, a preparation method therefore, and a use thereof. The method includes placing a carbon source precursor into a crucible and heating to 400° C-1000° C. at a heating rate of 0.2° C./min-30° C./min under an inert atmosphere, wherein the precursor includes any one or a combination of at least two of fossil fuel, biomass, resin, and organic chemicals; and carrying out heat treatment on the precursor at a temperature of 400° C. to 1000° C. for 0.5-48 hours to carbonize the precursor to obtain a carbon-based negative electrode material. The specific surface area of the anode material is less than 10 m²/g. and assembling the obtained electrode material into a sodium ion battery and then carrying out charging and discharging between 0 and 2.5 V, to obtain a voltage curve. The ramp capacity being above 180 mAh/g and the first-cycle Coulombic efficiency is above 75%.

A negative electrode material for a secondary battery is provided that can prevent deterioration of the cycle characteristic during the charge and discharge of the secondary battery and can enhance the initial coulombic efficiency. A negative electrode material for a secondary battery, including: a negative electrode active material containing a metal or a metal compound that can absorb and release an alkali metal ion or an alkaline earth metal ion, and containing a first carbon material that can absorb and release the alkali metal ion or the alkaline earth metal ion; and a conductive auxiliary containing a second carbon material different from the first carbon material, the negative electrode material having a capacity of 400 mAh/g or more, and the second carbon material being partially exfoliated graphite having a graphite structure in which graphite is partially exfoliated.

A pre-lithiation reaction chamber apparatus including a pre-lithiation reaction vessel which can prevent harmful effects caused by water that may be generated during pre-lithiation is provided. The pre-lithiation reaction vessel includes an electrolyte including a lithium salt, a negative electrode for a lithium secondary battery and a lithium ion-supplying member. Each of the negative electrode for the lithium secondary battery and the lithium ion-supplying member is at least partially in contact with the electrolyte. The pre-lithiation reaction chamber apparatus further includes a water-capturing vessel. The water-capturing vessel includes water-capturing powder, a container configured to receive the water-capturing powder, and a position-changing member configured to change a position of the water-capturing powder in the container.

The invention provides a preparation method of a bionic carbon negative electrode material used as a potassium ion battery negative electrode, and a product. The preparation method of the bionic carbon negative electrode material comprises the following steps: preparing a nitrogen-carbon compound (C3N4) intermediate; then catalyzing with a metal catalyst, and carbonizing at a high temperature of 700-900 DEG C; and finally, carrying out acid treatment to remove the metal catalyst, washing, and drying in a vacuum drying oven at 50-80 DEG C for 12-18 hours to obtain the biomimetic carbon negativeelectrode material similar to a biological cell structure. The negative electrode of the potassium ion battery is the biomimetic carbon negative electrode material prepared by the method, the potassium ion battery uses Prussian blue as a positive electrode, uses 4mol L<-1> of potassium bis(fluorosulfonyl) amide as an electrolyte, and uses 1, 2-dimethoxyethane as a solvent. The biomimetic carbon provided by the invention has excellent electrochemical properties such as high reversible capacity, excellent rate capability, excellent cycle performance and the like as a negative electrode materialof a potassium ion battery.