5246results about How to "Improve cycle life" patented technology

This invention provides a nanocomposite-based lithium battery electrode comprising: (a) A porous aggregate of electrically conductive nano-filaments that are substantially interconnected, intersected, physically contacted, or chemically bonded to form a three-dimensional network of electron-conducting paths, wherein the nano-filaments have a diameter or thickness less than 1 μm (preferably less than 500 nm); and (b) Sub-micron or nanometer-scale electro-active particles that are bonded to a surface of the nano-filaments with a conductive binder material, wherein the particles comprise an electro-active material capable of absorbing and desorbing lithium ions and wherein the electro-active material content is no less than 25% by weight based on the total weight of the particles, the binder material, and the filaments. Preferably, these electro-active particles are coated with a thin carbon layer. This electrode can be an anode or a cathode. The battery featuring such an anode or cathode exhibits an exceptionally high specific capacity, an excellent reversible capacity, and a long cycle life.

A method of producing a material capable of electrochemically storing and releasing a large amount of lithium ions is provided. The material is used as an electrode material for a negative electrode, and includes silicon or tin primary particles composed of crystal particles each having a specific diameter and an amorphous surface layer formed of at least a metal oxide, having a specific thickness. Gibbs free energy when the metal oxide is produced by oxidation of a metal is smaller than Gibbs free energy when silicon or tin is oxidized, and the metal oxide has higher thermodynamic stability than silicon oxide or tin oxide. The method of producing the electrode material includes reacting silicon or tin with a metal oxide, reacting a silicon oxide or a tin oxide with a metal, or reacting a silicon compound or a tin compound with a metal compound to react with each other.

This invention provides a nano-structured anode composition for a lithium metal cell. The composition comprises: (a) an integrated structure of electrically conductive nanometer-scaled filaments that are interconnected to form a porous network of electron-conducting paths comprising interconnected pores, wherein the nano-filaments have a transverse dimension less than 500 nm; and (b) micron- or nanometer-scaled particles of lithium, a lithium alloy, or a lithium-containing compound wherein at least one of the particles is surface-passivated or stabilized and the weight fraction of these particles is between 1% and 99% based on the total weight of these particles and the integrated structure together. Also provided is a lithium metal cell or battery, or lithium-air cell or battery, comprising such an anode. The battery exhibits an exceptionally high specific capacity, an excellent reversible capacity, and a long cycle life.

The invention relates to a high-capacity lithium-ion electrolyte, a battery and a preparation method of a battery, in particular to the high-capacity lithium-ion electrolyte and the battery using the high-capacity lithium-ion electrolyte and the preparation method of the battery. The electrolyte disclosed by the invention comprises lithium salt and non-aqueous organic solvent, and also consists of the following components in weight percent in terms of the total weight of the electrolyte: 0.5-7% of film-forming additive, 0-15% of flame-retardant additive, 2-10% of antiovefill additive, 0.01-2% of stabilizer and 0.01-1% of wetting agent; the electrolyte can enable the anode with high Ni content to work stably, and reduce the battery cost; the high-capacity lithium-ion battery can perform high ratio capacity and excellent safety and high temperature property and cyclic life fully due to the addition and synergetic functions of various functional additives.

This invention provides a hybrid nano-filament composition for use as a cathode active material. The composition comprises (a) an aggregate of nanometer-scaled, electrically conductive filaments that are substantially interconnected, intersected, or percolated to form a porous, electrically conductive filament network, wherein the filaments have a length and a diameter or thickness with the diameter or thickness being less than 500 nm; and (b) micron- or nanometer-scaled coating that is deposited on a surface of the filaments, wherein the coating comprises a cathode active material capable of absorbing and desorbing lithium ions and the coating has a thickness less than 10 μm, preferably less than 1 μm and more preferably less than 500 nm. Also provided is a lithium metal battery or lithium ion battery that comprises such a cathode. Preferably, the battery includes an anode that is manufactured according to a similar hybrid nano filament approach. The battery exhibits an exceptionally high specific capacity, an excellent reversible capacity, and a long cycle life.

The invention belongs to the fields of material synthesis and energy technology, and especially relates to a graphene/metal oxide composite cathode material for lithium ion batteries and a preparation method thereof. Grapheme is dispersed into various metal oxide precursor salt solutions; a graphene/metal oxide compound is obtained directly by a hydrothermal method, or an graphene/metal oxide compound is obtained by a liquid in-situ polymerization method or a coprecipitation process; and the graphene/metal oxide compound is obtained by heat treatment or hydrothermal treatment. In the invention, the novel three-dimensional composite cathode material of graphene-coated metal oxide or graphene-anchored metal oxide is prepared by carrying metal oxide particles with graphene as a carrier. The obtained composite material can be used as a lithium ion battery cathode, which has a high specific capacity, excellent cycle stability and rate capability, and is expected to be used as a lithium ion battery cathode material with a high energy density and a high power density.

An energy storage device includes a first electrode comprising a first material and a second electrode comprising a second material, at least a portion of the first and second materials forming an interpenetrating network when dispersed in an electrolyte, the electrolyte, the first material and the second material are selected so that the first and second materials exert a repelling force on each other when combined. An electrochemical device, includes a first electrode in electrical communication with a first current collector; a second electrode in electrical communication with a second current collector; and an ionically conductive medium in ionic contact with said first and second electrodes, wherein at least a portion of the first and second electrodes form an interpenetrating network and wherein at least one of the first and second electrodes comprises an electrode structure providing two or more pathways to its current collector.

An electric supercapacitor module is utilized as the primary power source for the propulsion unit of electrically powered vehicles. The vehicle operates in conjunction with roadway embedded wireless chargers which continually charge the vehicle's supercapacitor while the vehicle is in motion to maintain the motion and materially increase the vehicle's range without limitation.

Batteries including a lithium anode stabilized with a metal-lithium alloy and battery cells comprising such anodes are provided. In one embodiment, an electrochemical cell having an anode and a sulfur electrode including at least one of elemental sulfur, lithium sulfide, and a lithium polysulfide is provided. The anode includes a lithium core and a ternary alloy layer over the lithium core where the ternary alloy comprises lithium and two other metals. The ternary alloy layer is effective to increase cycle life and storageability of the electrochemical cell. In a more particular embodiment, the ternary alloy layer is comprised of lithium, copper and tin.

The invention provides for a fully electrically rechargeable metal-air battery systems and methods of achieving such systems. A rechargeable metal air battery cell may comprise a metal electrode an air electrode, and an aqueous electrolyte separating the metal electrode and the air electrode. In some embodiments, the metal electrode may directly contact the electrolyte and no separator or porous membrane need be provided between the air electrode and the electrolyte. Rechargeable metal air battery cells may be electrically connected to one another through a centrode connection between a metal electrode of a first battery cell and an air electrode of a second battery cell. Air tunnels may be provided between individual metal air battery cells. In some embodiments, an electrolyte flow management system may be provided.

Irreversible first cycle capacity loss in lithium secondary cells having a cell electrode based on a powdered material and a binder may be significantly decreased or eliminated by using an aliphatic or cycloaliphatic polyimide binder. Compared to conventional polyimide binders prepared by reacting an aromatic dianhydride and a diamine, the disclosed polyimide binders have decreased aromatic carbonyl content, may be less likely to undergo electrochemical reduction, and may be less likely to consume electrons that might otherwise help lithiate the electrode.

Disclosed is a negative active material for a rechargeable lithium battery that includes graphite particles, silicon micro-particles attached on the graphite particles and a carbon film partially or totally coated on the graphite particles.

Disclosed is a wind and solar hybrid power system based on an ultra-capacitor battery hybrid system, which includes a DC/DC buck converter (20), an AC/DC converter (30), an ultra-capacitor assembly (40), a DC/AC converter (50), a battery assembly (60), a battery charge circuit (700), a photovoltaic array (70), a wind generator (80) and an oil engine/commercial power interface (90). The photovoltaic array (70) is connected with the ultra-capacitor assembly (40) through the DC/DC buck converter (20); the wind generator (80) and the oil engine/commercial power interface (90) are connected with the ultra-capacitor assembly (40) through the AC/DC converter (30); the ultra-capacitor assembly (40) charges the battery assembly (60) through the battery charge circuit (700); the ultra-capacitor assembly and the battery assembly provides a definite power buffering to the system so that to maintain a stable voltage of the power supply. The wind and solar hybrid power system of the invention can provides uninterrupted power to the telecommunication system and resident living in the undeveloped areas where the power distribution network can not reach.

A positive active material of a lithium-sulfur battery includes a sulfur-conductive agent-agglomerated complex in which a conductive agent particle is attached onto a surface of a sulfur particle having an average particle size less than or equal to 7 μm. The sulfur-conductive agent-agglomerated complex is manufactured by mixing a sulfur powder and a conductive agent powder to form a mixture, and milling the mixture.

The present invention relates generally to electrolyte materials. According to an embodiment, the present invention provides for a solid polymer electrolyte material that is ionically conductive, mechanically robust, and can be formed into desirable shapes using conventional polymer processing methods. An exemplary polymer electrolyte material has an elastic modulus in excess of 1×10⁶ Pa at 90 degrees C. and is characterized by an ionic conductivity of at least 1×10⁻⁵ Scm−1 at 90 degrees C. An exemplary material can be characterized by a two domain or three domain material system. An exemplary material can include material components made of diblock polymers or triblock polymers. Many uses are contemplated for the solid polymer electrolyte materials. For example, the present invention can be applied to improve Li-based batteries by means of enabling higher energy density, better thermal and environmental stability, lower rates of self-discharge, enhanced safety, lower manufacturing costs, and novel form factors.

The invention provides a PVDF-coated lithium-ion battery separator and a preparation method thereof. The PVDF-coated lithium-ion battery separator comprises a base film and a coating, wherein the coating coats a single side or double sides of the base film; the coating is obtained by coating and drying slurry; and the coating is 0.1-0.5 micron in thickness and contains evenly arranged PVDF spherical particles. According to the PVDF-coated lithium-ion battery separator, a traditional technology that an existing PVDF-coated lithium-ion battery separator takes oil substances of acetone and the like as solvents is abandoned. Water is adopted as the solvent of a PVDF material; and no a thickening agent is added, so that the low-viscosity water-based PVDF coating slurry is obtained; an ultra-thin coating of which the PVDF particles are regularly arranged and which is relatively loose is obtained after the slurry is coated; the ultra-thin coating improves the hardness of a pole piece and the effective utilization space of the battery when effectively bonded to the lithium-ion battery separator and the pole piece; and the ventilation loss caused by the thickness of the coating is reduced.

The invention discloses a large-capacity high-power polymer lithium iron phosphate power battery. The weight ratio of anode slurry is as follows: 81 to 85 percent of lithium iron phosphate, 1 to 5.5 percent of superconduction carbon, 0 to 2.5 percent of conductive carbon soot, 0 to 4 percent of conductive black lead, 0 to 2.5 percent of crystalline flake graphite, 0 to 2 percent of carbon nanometer tube as well as 6 to 7.5 percent of polyvinylidene fluoride; the weight ratio of cathode slurry is as follows: 89 to 91 percent of cathode material, 1 to 3.5 percent of superconduction carbon, 0 to 2 percent of conductive carbon soot, 0 to 4 percent of conductive black lead, 2.5 to 3.5 percent of styrene-butadiene rubber as well as 1.5 to 2 percent of sodium carboxymethyl cellulose; the steps for preparing the battery are as follows: preparing slurry, coating the anode and the cathode, rolling and pressing a polar plate, transversely and separately cutting the polar plate, baking the polar plate, welding the polar ears of the anode and the cathode, preparing a battery cell, putting the electric core into a shell and sealing, baking the electric core, injecting liquid into the battery as well as forming the battery and dividing the volume of the battery. The invention relates to a lithium-ion secondary battery which can provide drive energies for electric tools, electric bicycles, motor cars and electric vehicles.

A separator membrane for use in silver-zinc batteries is produced by extruding a blend of two fillers with the same chemical formula but different particle size. A polyolefine polymer and a plasticizer are blended and extruded to form a thin sheet of 1 to 10 mil thickness. The plasticizer is then extracted to leave submicron voids in the membrane. Plasticizers are added as processing aids, and can be either soluble or insoluble in water, and include petroleum oils, lubricating oils, fuel oils, and natural oils such as tall oils and linseed oils. The oil are then extracted from the membrane by conventional procedures such as single stage extraction using a suitable solvent. Commercially available wetting agents known to the art such as dodecylphenoxy polyethoxy ethanol and isooctyl phenyl polyethoxy ethanol are coated onto the sheet to improve wettability. The sheet is then dried, and boiled in distilled water for one minute or more, before being finally dried.

Disclosed is a lithium secondary battery including a positive electrode comprising a combination of positive active materials. The combination includes a material represented by one or both of Formulae 1 and 2; and a material of Formula 3 as follows:

Li_aNi_bMn_cM_dO₂   (Formula 1)

where 0.90≦a≦1.2; 0.5≦b≦0.9; 0<c<0.4; 0≦d≦0.2;

Li_aNi_bCo_cMn_dM_eO₂   (Formula 2)

where 0.90≦a≦1.2, 0.5≦b≦0.9, 0<c<0.4, 0<d<0.4, and 0≦e≦0.2;

Li_aCoM_bO₂   (Formula 3)

where 0.90≦a≦1.2 and 0≦b≦0.2; and each M of Formulae 1-3 is independently selected from the group consisting of Mg, Ca, Sr, Ba, Ra, Sc, Y, Ti, Zr, Hf, Rf, V, Nb, Ta, Db, Cr, Mo, W, Sg, Tc, Re, Bh, Fe, Ru, Os, Hs, Rh, Ir, Pd, Pt, Cu, Ag, Au, Zn, Cd, B, Al, Ga, In, Tl, Si, Ge, Sn, P, As, Sb, Bi, S, Se, Te, Po, and combinations.

The invention discloses a doped modified lithium nickel cobalt manganese material, a preparation method thereof and a lithium ion battery. A secondary particle of the doped modified lithium nickel cobalt manganese material is composed of a primary particle and is spherical or spherical-like in shape, and the surface of the primary particle is non-uniformly doped with a nano metal oxide layer. In the preparation method, a precursor of the lithium nickel cobalt manganese material is doped with nano metal oxides during a synthesis stage and undergoes doping modification. Compared with the prior art, the doped modified lithium nickel cobalt manganese material is used as an anode activity material of the lithium ion battery, under a charge/discharge condition of 4.45 V, has good circulation and good thermal stability, and can meet requirements of high energy density, high power density, long service life and high safety of the lithium ion battery.

The invention discloses a hydrothermal synthesis method of lithium-ion battery anode material of lithium iron phosphate, relating two kinds of metal phosphate. The steps are as follows: lithium source and phosphorus source are dissolved in water or mixed with water, and added into the reaction autoclave, the quaternary cationic surfactants and the alkylphenols polyoxyethylene ethers nonionic surfactant is also added into the reaction autoclave, the air in the dead volume of the autoclave inside is purged by the inert gas, the autoclave is sealed and heated to 40-50 DEG C with stirring, a feed valve and an exhaust valve are opened, pure ferrous salting liquid is added into the autoclave, and then the autoclave is sealed for the reaction of the material at 140 to 180 DEG C for 30 to 480 minutes; the mixture ratio of the invention is set as follows: the molar ratio of Li, Fe and P is 3.0-3.15:1:1.0-1.15, and then the resultant is filtered, washed, dried and carbon-coated, thus the lithium iron phosphate is obtained. The lithium iron phosphate which is produced by the invention has the advantages that: the electrochemical performance is excellent, the particle size distribution of which the D50 is between 1.5 um to 2 um is even, the phase purity is above 99 percent and the electronic conductivity of the material is improved.

The invention discloses a method for preparing silicon carbon cathode materials for lithium ion battery. The method includes synthesizing silicon oxide micro-spheres (SiOx micro-spheres), and then sequentially mixing, coating and carbonizing the SiOx micro-spheres and the pitch solution. The method for preparing silicon oxide (SiOx) / carbon (C) composite materials and the prepared silicon carbon cathode materials for lithium ion battery also disclose the silicon carbon cathode materials for lithium ion battery, the materials for lithium ion battery are prepared by mixing the SiOx micro-spheres/ C micro-spheres with artificial graphite. According to the method for preparing silicon oxide (SiOx) / carbon (C) composite materials, the rate of decay of the silicon carbon cathode materials is effectively prolonged, the circulation performance of the silicon carbon cathode materials is improved and the first circulation efficiency of the silicon carbon cathode materials is increased.