10595 results about "Cathode material" patented technology

In an active-type electroluminescent (EL) display, a conductor interconnecting a cathode (55) of an EL panel (30, 40) and a connection terminal of a signal input substrate (35) has a multilayer structure formed of a cathode material and a conductive material used in a thin-film transistor forming step. The conductor may be formed of a conductive material used in a thin film transistor forming step. A metal material for a gate electrode or drain electrode is preferably used as the conductive material. The connection conductor structure can reduce the electrical resistance of the connection conductor, thus preventing a decrease in display intensity of an EL display.

A number of materials with the composition Li_1+xNi_αMn_βCo_γM′_δO_2−zF_z (M′=Mg,Zn,Al,Ga,B,Zr,Ti) for use with rechargeable batteries, wherein x is between about 0 and 0.3, α is between about 0.2 and 0.6, β is between about 0.2 and 0.6, γ is between about 0 and 0.3, δ is between about 0 and 0.15, and z is between about 0 and 0.2. Adding the above metal and fluorine dopants affects capacity, impedance, and stability of the layered oxide structure during electrochemical cycling.

The invention discloses a carbon/silicon/carbon nano composite structure cathode material and a preparation method thereof, belonging to the technical field of electrochemical power supply technologies. The cathode material consists of a carbon-based conductive substrate, nano silicon and a nano carbon coating layer, wherein the nano silicon is uniformly distributed on the carbon-based conductive substrate; the nano carbon coating layer is arranged on the surface of the nano silicon; the carbon-based conductive substrate is porous carbon, a carbon nanotube or graphene; the nano silicon exists in the state of nanoparticles or nano films; the weight percentage of the nano silicon in the cathode material is 10-90 percent; and the thickness of the nano carbon coating layer is 0.1-10 nanometers. The preparation method comprises the following steps of: depositing nano silicon on the carbon substrate in a reaction space in oxygen-free atmosphere by adopting a chemical vapor deposition process; and coating nano carbon on the surface of the nano silicon by adopting the chemical vapor deposition process. In the obtained carbon/silicon/carbon composite cathode material, the volume change of a silicon electrode material is controlled effectively in the charging and discharging processes, the electrode structure is kept complete, the circulation volume is large, the circulation service life is long, and the electrochemical performance is high.

The invention provides a comprehensive recovering method of waste lithium iron phosphate batteries, which has simple and reasonable process, low recovering cost and high added value. The method comprises the following steps: utilizing an organic solvent to dissolve an adhesive on battery cell fragments, and realizing the separation of lithium iron phosphate material and clean aluminum and copper foils through screening, wherein the aluminum and copper foils are recovered by smelting; utilizing a NaOH solution to remove residual aluminum foil scraps in the lithium iron phosphate material, and removing graphite and remaining adhesive by heat treatment; after dissolving the lithium iron phosphate with acid, utilizing sodium sulphide to remove copper ions, and utilizing the NaOH solution or ammonia solution to allow iron, lithium and phosphorus ions in the solution to generate sediments; adding iron source, lithium source or phosphorus source compounds to adjust the molar ratio of iron, lithium and phosphorus; and finally adding a carbon source, and obtaining a lithium iron phosphate cathode material through ball milling and calcination in inert atmosphere. After the treatment of the steps, the recovery rate of valuable metals in the batteries is more than 95%, and the comprehensive recovery rate of the lithium iron phosphate cathode material is more than 90%.

The invention is related to a cathode material comprising particles having a lithium metal phosphate core and a pyrolytic carbon deposit, said particles having a synthetic multimodal particle size distribution comprising at least one fraction of micron size particles and one fraction of submicron size particles, said lithium metal phosphate having formula LiMPO₄ wherein M is at least Fe or Mn.

Said material is prepared by method comprising the steps of providing starting micron sized particles and starting submicron sized particles of at least one lithium metal phosphate or of precursors of a lithium metal phosphate; mixing by mechanical means said starting particles; making a pyrolytic carbon deposit on the lithium metal phosphate starting particles before or after the mixing step, and on their metal precursor before or after mixing the particles; optionally adding carbon black, graphite powder or fibers to the said lithium metal phosphate particles before the mechanical mixing.

The invention is directed in a first aspect to a sulfur-carbon composite material comprising: (i) a bimodal porous carbon component containing therein a first mode of pores which are mesopores, and a second mode of pores which are micropores; and (ii) elemental sulfur contained in at least a portion of said micropores. The invention is also directed to the aforesaid sulfur-carbon composite as a layer on a current collector material; a lithium ion battery containing the sulfur-carbon composite in a cathode therein; as well as a method for preparing the sulfur-composite material.

A method and apparatus for making thin-film batteries having composite multi-layered electrolytes with soft electrolyte between hard electrolyte covering the negative and/or positive electrode, and the resulting batteries. In some embodiments, foil-core cathode sheets each having a cathode material (e.g., LiCoO₂) covered by a hard electrolyte on both sides, and foil-core anode sheets having an anode material (e.g., lithium metal) covered by a hard electrolyte on both sides, are laminated using a soft (e.g., polymer gel) electrolyte sandwiched between alternating cathode and anode sheets. A hard glass-like electrolyte layer obtains a smooth hard positive-electrode lithium-metal layer upon charging, but when very thin, have randomly spaced pinholes/defects. When the hard layers are formed on both the positive and negative electrodes, one electrode's dendrite-short-causing defects on are not aligned with the other electrode's defects. The soft electrolyte layer both conducts ions across the gap between hard electrolyte layers and fills pinholes.

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.

A method and apparatus for making thin-film batteries having composite multi-layered electrolytes with soft electrolyte between hard electrolyte covering the negative and/or positive electrode, and the resulting batteries. In some embodiments, foil-core cathode sheets each having a cathode material (e.g., LiCoO₂) covered by a hard electrolyte on both sides, and foil-core anode sheets having an anode material (e.g., lithium metal) covered by a hard electrolyte on both sides, are laminated using a soft (e.g., polymer gel) electrolyte sandwiched between alternating cathode and anode sheets. A hard glass-like electrolyte layer obtains a smooth hard positive-electrode lithium-metal layer upon charging, but when very thin, have randomly spaced pinholes/defects. When the hard layers are formed on both the positive and negative electrodes, one electrode's dendrite-short-causing defects on are not aligned with the other electrode's defects. The soft electrolyte layer both conducts ions across the gap between hard electrolyte layers and fills pinholes.

A lithium-ion battery includes a cathode that includes an active cathode material. The active cathode material includes a cathode mixture that includes a lithium cobaltate and a manganate spinel a manganate spinel represented by an empirical formula of Li_(1+x1)(Mn_1−y1A′_y2)_2−x2O_z1. The lithium cobaltate and the manganate spinel are in a weight ratio of lithium cobaltate: manganate spinel between about 0.95:0.05 to about 0.55:0.45. A lithium-ion battery pack employs a cathode that includes an active cathode material as described above. A method of forming a lithium-ion battery includes the steps of forming an active cathode material as described above; forming a cathode electrode with the active cathode material; and forming an anode electrode in electrical contact with the cathode via an electrolyte.

In order to increase the capacity of an “all-solid” type micro-battery, the layer of electrolyte is structured: transversing cavities are created in the flat layer, advantageously at the level of patches of collector material, then filled by anode or cathode material.

A method of producing nano-scaled graphene platelets with an average thickness smaller than 30 nm from a layered graphite material. The method comprises (a) forming a carboxylic acid-intercalated graphite compound by an electrochemical reaction which uses a carboxylic acid as both an electrolyte and an intercalate source, the layered graphite material as an anode material, and a metal or graphite as a cathode material, and wherein a current is imposed upon the cathode and the anode at a current density for a duration of time sufficient for effecting the electrochemical reaction; (b) exposing the intercalated graphite compound to a thermal shock to produce exfoliated graphite; and (c) subjecting the exfoliated graphite to a mechanical shearing treatment to produce the nano-scaled graphene platelets. Preferred carboxylic acids are formic acid and acetic acid. The exfoliation step in the instant invention does not involve the evolution of undesirable species, such as NO_x and SO_x, which are common by-products of exfoliating conventional sulfuric or nitric acid-intercalated graphite compounds. The nano-scaled platelets are candidate reinforcement fillers for polymer nanocomposites. Nano-scaled graphene platelets are much lower-cost alternatives to carbon nano-tubes or carbon nano-fibers.

The invention relates to binary, ternary and quaternary lithium phosphates of general formula Li(FexM<1>yM<2>z)PO4 wherein M<1 >represents at least one element of the group comprising Sc, Ti, V, Cr, Mn, Co, Ni, Cu, Zn, Be, Mg, Ca, Sr, Ba, Al, Zr, and La; M<2 >represents at least one element of the group comprising Sc, Ti, V, Cr, Mn, Co, Ni, Cu, Zn, Be, Mg, Ca, Sr, Ba, Al, Zr, and La; x=between 0.5 and 1, y=between 0 and 0.5, z=between 0 and 0.5, provided that x+y+z=1, or x=0, y =1 and z=0. The said lithium phosphates can be obtained according to a method whereby precursor compounds of elements Li, Fe, M<1 >and/or M<2 >are precipitated from aqueous solutions and the precipitation product is dried in an inert gas atmosphere or a reducing atmosphere at a temperature which is between room temperature and approximately 200° C. and tempered at a temperature of between 300° C. and 1000° C. The inventive lithium phosphates have a very high capacity when used as cathode material in lithium accumulators.

In one embodiment, an active cathode material comprises a mixture that includes: at least one of a lithium cobaltate and a lithium nickelate; and at least one of a manganate spinel represented by an empirical formula of Li_(1+x1)(Mn_1−y1A′_y1)_2−x1O_z1 and an olivine compound represented by an empirical formula of Li_(1−x2)A″_x2MPO₄. In another embodiment, an active cathode material comprises a mixture that includes: a lithium nickelate selected from the group consisting of LiCoO₂-coated LiNi_0.8Co_0.15Al_0.05O₂, and Li(Ni_1/3Co_1/3Mn_1/3)O₂; and a manganate spinel represented by an empirical formula of Li_(1+x7)Mn_2−y7O_z7. A lithium-ion battery and a battery pack each independently employ a cathode that includes an active cathode material as described above. A method of forming a lithium-ion battery includes the steps of forming an active cathode material as described above; forming a cathode electrode with the active cathode material; and forming an anode electrode in electrical contact with the cathode via an electrolyte. A system comprises a portable electronic device and a battery pack or lithium-ion battery as described above.

The invention discloses a preparation method of a silicon and carbon-coated graphene composite cathode material. The technical problem to be solved is to enhance the electronic conductivity of the silicon-based cathode material, buffer the volume effect produced in the process of deintercalation of the lithium in the silicon-based cathode material and enhance the structure stability in the circulation process of the material at the same time. The material is prepared by using a spray drying-thermally decomposing treatment process in the invention. The preparation method comprises the following steps of: evenly dispersing nano silicon and graphite micro powder in a dispersion solution of oxidized graphene, carrying out thermal treatment under an inert protection atmosphere after spray drying, subsequently cooling along a furnace to obtain the silicon and carbon-coated graphene composite cathode material. The extra binder does not need to add in the process of manufacturing balls in the invention and the outer oxidized graphene is thermally reduced in situ to graphene in the thermal treatment process of the composite precursor, so that the process is simple and easy to operate; and the practical degree is high. The prepared composite material has the advantages of great reversible capacity, designable capacity, good cycling performance and high-current discharging performance, high tap density and the like.

The invention discloses a grapheme/silicon composite material for a lithium ion battery cathode material and a preparation method thereof, belonging to the fields of electrochemistry and new energy materials. The method comprises the following steps of: using graphite as a raw material; oxidizing the graphite into oxidized graphite by adopting oxidants of concentrated sulfuric acid and potassium permanganate; then, ultrasonically stripping the oxidized graphite to prepare oxidized graphene; mixing oxidized graphene in different proportions with nano silicon powder; ultrasonically dispersing, filtering or directly drying into a cake/film; and roasting under a reduction atmosphere to prepare self-support graphene/silicon composite film materials in different proportions. Proved by electrochemistry tests, the graphene/silicon composite film material prepared by the method has higher specific capacity and cycle stability, simple preparation method and easy mass production and consequently is an ideal high-energy lithium ion battery cathode material.

A composition suitable for use as a cathode material of a lithium battery includes a core material having an empirical formula Li_xM′_zNi_1−yM″_yO₂. “x” is equal to or greater than about 0.1 and equal to or less than about 1.3. “y” is greater than about 0.0 and equal to or less than about 0.5. “z” is greater than about 0.0 and equal to or less than about 0.2. M′ is at least one member of the group consisting of sodium, potassium, nickel, calcium, magnesium and strontium. M″ is at least one member of the group consisting of cobalt, iron, manganese, chromium, vanadium, titanium, magnesium, silicon, boron, aluminum and gallium. A coating on the core has a greater ratio of cobalt to nickel than the core. The coating and, optionally, the core can be a material having an empirical formula Li_x1A_x2Ni_1−y1−z1Co_y1B_z1O_a. “x1” is greater than about 0.1 a equal to or less than about 1.3. “x2,”“y1” and “z1” each is greater than about 0.0 and equal to or less than about 0.2. “a” is greater than 1.5 and less than about 2.1. “A” is at least one element selected from the group consisting of barium, magnesium, calcium and strontium. “B” is at least one element selected from the group consisting of boron, aluminum, gallium, manganese, titanium, vanadium and zirconium.

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.

The invention provides a method for preparing a porous silicon/carbon composite material by using diatomite as the raw material, which is characterized by comprising the following steps of: with the diatomite as the raw material, performing simple refinement and purification processing to obtain silicon with a porous structure by means of metallothermic reduction; performing mechanical ball-milling with the carbon materials and/or precursors of carbon, hydro-thermal carbonization, pyrolytic carbonization or chemical vapor deposition to prepare the porous silicon/carbon composite material. Thecomposite material can be directly used as the cathode of the lithium ion battery, or can be mixed with other cathode materials to be used as the cathode materials of the lithium ion battery. Compared with a pure silicon material as the cathode material of the lithium ion battery, the porous silicon/carbon composite material has the advantages that the first reversible capacity and the circulation stability of the material are greatly improved. In the method, the inexpensive and accessible natural minerals are used as the raw materials, thus the cost is low and the preparation method is simple.

A process for producing an electrode for an alkali metal battery, comprising: (a) Continuously feeding an electrically conductive porous layer to an anode or cathode material impregnation zone, wherein the conductive porous layer has two opposed porous surfaces and contain interconnected conductive pathways and at least 70% by volume of pores; (b) Impregnating a wet anode or cathode active material mixture into the porous layer from at least one of the two porous surfaces to form an anode or cathode electrode, wherein the wet anode or cathode active material mixture contains an anode or cathode active material and an optional conductive additive mixed with a liquid electrolyte; and (c) Supplying at least a protective film to cover the at least one porous surface to form the electrode.