1252 results about "Composite cathode" patented technology

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.

There is provided a mother-battery containing at least the following films: an anode of metallic lithium or sodium, a polymer electrolyte which is conductive towards the alkaline ions of the anode and also acts as a separator between the electrodes, and a composite cathode consisting of a compound which is reducible to lithium or sodium, an additive of electronic conduction and a polymer electrolyte binder. The mother battery also includes an electronically conductive thin coating on the external face of the anode and, possibly of the cathode, in which the conductive material is chemically inert towards the electrode material and which also serves to establish permanent electrical contacts on the external faces. The laminated mother-battery of larger surface area and at least partially charged is thereafter subjected to a sharp mechanical cutting out to give thin polymer electrolyte batteries with lithium or sodium anode. The thus cut out batteries preserve substantially their voltage after mechanical cutting out which is recovered by a mechanism of self-healing.

Composite cathode active materials having a large diameter active material and a small diameter active material are provided. The ratio of the average particle diameter of the large diameter active material to the average particle diameter of the small diameter active material ranges from about 6:1 to about 100:1. Mixing the large and small diameter active materials in a proper weight ratio improves packing density Additionally, including highly stable materials and highly conductive materials in the composite cathode active materials improves volume density, discharge capacity and high rate discharge capacity.

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.

An impregnated solid state composite cathode is provided. The cathode contains a sintered porous active material, in which pores of the porous material are impregnated with an inorganic ionically conductive amorphous solid electrolyte. A method for producing the impregnated solid state composite cathode involves forming a pellet containing an active intercalation cathode material; sintering the pellet to form a sintered porous cathode pellet; impregnating pores of the sintered porous cathode pellet with a liquid precursor of an inorganic amorphous ionically conductive solid electrolyte; and curing the impregnated pellet to yield the composite cathode.

The invention relates to a lithium ion battery composite cathode material and a preparation method. The cathode material comprises a hard carbon precursor material containing hetero atoms, and natural spherical graphite, wherein the hard carbon precursor material selects one or more than two of phenolic resin, polyfurfural, furan resin, polyvinyl alcohol, epoxide resin or polyacrylonitrile as raw materials, and accounts for 5 to 45 percent of the natural spherical graphite by mass; modifier of the hetero atoms is boron-containing modifier including boric acid and diboron trioxide, phosphor-containing modifier including phosphoric acid and phosphorus pentoxide, and nitrogen-containing modifier HNO3; and one of the modifiers accounts for 5 to 35 percent of the hard carbon precursor by mass. An analog battery formed by the cathode material which is prepared by the method has the capacity over 350 mAH/g and first coulomb efficiency up to 95.8 percent, and has good circulation performance. The preparation method has the advantages of low cost and simple process.

The invention provides a silicon-carbon composite cathode material for preparing a lithium-ion battery at the room temperature and a preparation method thereof. The composite cathode material is a material with a nuclear shell structure and comprises the following proportional elements: 0.01-10% of simple substance silicon and 90-99.9% of carbon. With regard to the preparation method, silicon powder and graphite are mixed for ball grinding and then added with bitumen or polymer cladding material for ball grinding again, after the treatment of carbonization, the mixture is crushed and sieved to obtain the material containing 0.01-10wt% of silicon and 10-99.9% of carbon. The capacity of the material is more than 350mAh/g, the cycle efficiency of the material is larger than 90% for the first time, and keeps larger than 80% after 200 cycles, and the material has good charging and discharging property.

The invention relates to a spinel nickel manganese acid lithium and layered lithium-rich manganese-based composite cathode material with a core-shell structure and a preparation method thereof, which belongs to the technical field of material synthesis. The prepared lithium ion composite cathode material takes a layered lithium-rich manganese-based Li[Lia(NixCoyMnz)]O2 as a core material, takes spinel nickel manganese acid lithium LiNi0.5Mn1.5O4 as a shell material; a coprecipitation method is employed to obtain a core-shell precursor, the core-shell precursor and the lithium source are uniformly mixed and calcined to obtain the spinel nickel manganese acid lithium and layered lithium-rich manganese-based composite cathode material with the core-shell structure. According to the invention, the layered lithium-rich manganese-based is taken as the core material, and the spinel nickel manganese acid lithium is taken as the shell material; under the prerequisite that material gram capacity is kept, material structural stability is increased, material cycle, multiplying power and safety performances are improved, function composite and complementation of the core material and the shell layer material can be realized, and the problem that high capacity and high security can not be achieved simultaneously is solved. The composite cathode material has the advantages of simple process and obviously increased performance.

A high capacity solid state composite cathode contains an active cathode material dispersed in an amorphous inorganic ionically conductive metal oxide, such as lithium lanthanum zirconium oxide and/or lithium carbon lanthanum zirconium oxide. A solid state composite separator contains an electronically insulating inorganic powder dispersed in an amorphous, inorganic, ionically conductive metal oxide. Methods for preparing the composite cathode and composite separator are provided.

A hybrid bipolar plate assembly comprises a metallic anode plate, a polymeric composite cathode plate, and a metal layer positioned between the metallic anode plate and the composite cathode plate. The metallic anode and composite cathode plates can further comprise an adhesive sealant applied around the outer perimeter to prevent leaking of coolant. The assembly can be incorporated into a device comprising a fuel cell. Further, the device can define structure defining a vehicle powered by the fuel cell.

The invention discloses a silicon-carbon composite cathode material with a three-dimensional preformed hole structure and a preparation method thereof. According to the composite cathode material, a carbon material having high electric conductivity and a stable structure is used as a matrix for dispersedly containing high-volume silicon particles, and proper three-dimensional expansion spaces are reserved around one or several silicon particles. The preparation method comprises the following steps of: carrying out surface modification on the silicon particles; coating the silicon particles by silicon dioxide; coating the silicon dioxide/silicon composite particles by carbon source precursors; carrying out high-temperature carbonization treatment; and removing a silicon dioxide template, and the like. When the composite material prepared by the preparation method is used for a lithium ion battery, the reversible specific capacity is high, and the cycle performance is excellent. The silicon-carbon composite cathode material has the advantages of simple preparation process and wide raw material resource and is suitable for industrial production.

The invention discloses a carbon nano tube-containing sulfur-based composite cathode material and a preparation method thereof. The sulfur-based composite cathode material is a ternary composite material AxByCz, wherein A is a dehydrocyclization product of an acrylonitrile-itaconic acid copolymer; B is elemental sulfur; C is a carbon nano tube; x is more than or equal to 30 weight percent and less than or equal to 60 weight percent; y is more than or equal to 30 weight percent and less than or equal to 60 weight percent; and z is more than or equal to 1 weight percent and less than or equal to 20 weight percent. The preparation method comprises the following steps of: in-situ polymerizing an acrylonitrile-itaconic acid monomer on the surface of the multi-wall carbon nano tube, and performing thermal treatment on both of the acrylonitrile-itaconic acid copolymer and the elemental sulfur, so that the sulfur is uniformly dispersed in a substrate formed by the dehydrocyclization of the acrylonitrile-itaconic acid copolymer. The carbon nano tube-containing sulfur-based composite cathode material and a lithium cathode form a secondary lithium-sulfur battery which is charged and discharged at the room temperature. The carbon nano tube-containing sulfur-based composite cathode material has the reversible specific capacity of 697 mAh/g and high cyclical stability.

A method of preparing LiFePO₄/Li₃V₂(PO₄)₃ composite cathode materials and their applications as cathode materials for lithium ion batteries are disclosed. The preparation method includes the following steps: (A) providing a mixture of iron powder, lithium salt, vanadium salt, and a phosphate salt whereafter these compounds are dissolved into a mixed acid solution; (B) drying the solution in order to obtain precursor powders; and (C) heating the precursor powders at a temperature ranging between 400 and 1000° C. to form LiFe_1-y′V_y′PO₄/Li₃V_2-y″Fe_y″(PO₄)₃ composite powders. Alternatively, prepare the composite cathode by preparing olivine LiFe_1-y′V_y′PO₄ and monoclinic Li₃V_2-y′Fe_y″(PO₄)₃ powders as in previous procedures followed by mixing adequately. The low cost of iron powder thus facilitates to prepared composite cathode materials exhibiting higher electrical conductivity and superior cycling performance at high C rates than those of olivine LiFe_1-y′V_y′PO₄ and monoclinic Li₃V_2-y″Fe_y″(PO₄)₃. The invention will help the development of the lithium ion batteries and related industries.

The present invention relates to a cathode active material with whole particle concentration gradient for a lithium secondary battery, a method for preparing same, and a lithium secondary battery having same, and more specifically, to a composite cathode active material, a method for manufacturing same, and a lithium secondary battery having same, the composite cathode active material having excellent lifetime characteristics and charge/discharge characteristics through the stabilization of crystal structure as the concentration of a metal comprising the cathode active material shows concentration gradient in the whole particle, and having thermostability even in high temperatures.

The invention discloses a lithium ion battery phosphatic composite cathode material and a preparation method thereof. The composite material is a multinuclear core shell structure composed of a plurality of cores and a housing layer, the cores are lithium iron phosphate particles wrapped by lithium vanadium phosphate and the housing layer is amorphous carbon. Preparation of the lithium iron phosphate particles wrapped by lithium vanadium phosphate comprises the following steps: preparing precursor sol with a sol gel method, adding lithium iron phosphate powder to disperse uniformly, carrying out spray drying on the above mixture, calcining the above resultant in inert gas, and followed by cooling and grinding to obtain the lithium iron phosphate particles wrapped by lithium vanadium phosphate. Preparation of the composite cathode material comprises the following steps: dissolving a carbon source compound into deionized water, adding core materials, dispersing the above resultant uniformly, carrying out second spray drying, calcining the above resultant in inert gas, and followed by cooling to obtain the composite cathode material. The composite material prepared in the invention has good electronic conduction performance, good ionic conduction performance and excellent electrochemistry performance. Because of existence of lithium vanadium phosphate, energetic density of a material is raised. Because of the multinuclear core shell structure like nano/micro structures, the composite material has good processing performance, and tap density of the material is greatly raised.

The invention discloses a preparation method for a composite cathode material of a lithium ion battery by means of spray drying pyrolysis treatment. The preparation method includes the steps: dissolving a first type of binder organic carbon source into solvent of a proper quantity, adding a silicon source, a second type of binder and a dispersing agent, dispersing uniformly, adding graphite, dispersing for a certain time, subjecting uniformly dispersed suspension to spray drying, and using the first type of binder organic carbon source to bond the silicon source, the graphite and the second type of binder particles into spherical or spherical-like forms to obtain a composite precursor; and transferring the precursor into a shielding atmosphere for sintering, heating the second type of binder to a certain temperature to be melted into a liquid crystal state, bonding the particle silicon source and the graphite into cores, subjecting the organic carbon source to pyrolysis at the high temperature to form a coating, and furnace cooling to obtain the carbon-silicon composite cathode material of the lithium ion battery. The preparation method is simple, easy in implementation and high in practicality. The carbon-silicon composite prepared by the method has the advantages of high reversible capacity, designable capacity, high circulating performance and high-current discharging performance, high tap density and the like.

The invention relates to a water-system asymmetric super-capacitor based on NiCo2S4 and a NiCo2S4 composite material, and belongs to the technical field of chemical power supplies. The super-capacitor comprises the following materials: (1) NiCo2S4 and the NiCo2S4 composite cathode material (including AC/NiCo2S4, CQDs/NiCo2S4, GNP/NiCo2S4, CNTs/NiCo2S4 and CF/NiCo2S4) which serve as an anode, (2) a carbon-based anode material (including AC, CQDs, GNP, CNTs and CF) which serves as an cathode, (3) a KOH solution which serves as an electrolytic solution, (4) a diaphragm, (5) an anode gasket, (6) a cathode gasket, and (7) a housing. The prepared asymmetric super-capacitor has the voltage window of 1.5 V and is high in energy density, excellent in cyclic stability, low in internal resistance, easy to prepare, safe to use, low in cost, environment-friendly and suitable for commercialized production.

The invention discloses a nitrogen-doped carbon-clad manganese oxide lithium ion battery composite cathode material, and a preparation method and an application of the composite cathode material. The composite material is composited by nanoscale manganese oxide and dopamine, wherein manganese oxide is spherical. The method comprises the steps of mixing a prepared spherical manganese oxide nano particle and dopamine hydrochloride, performing filtering, washing and drying to obtain a manganese oxide and polydopamine composite, and then converting a polymerization layer into a nitrogen-doped carbon layer by high-temperature carbonization. The prepared nitrogen-doped carbon-clad manganese oxide (MnO@NC) lithium ion battery composite cathode material is stable in structure and good in conductivity, and has excellent rate capability and cycling stability as a lithium ion battery cathode material; and polymerization of the dopamine is only completed at a room temperature and under a slightly alkaline condition, so that the composite cathode material is low in cost, low in energy consumption, convenient to control and environment-friendly, is suitable for a practical application of a lithium ion battery, and can realize industrial mass production.

A composite cathode active material including an overlithiated metal oxide having a layered structure, a material having an olivine structure, and one or more of: an inorganic material, and nitrogen atoms doped in the material having an olivine structure. The inorganic material includes a nitride or carbide of a non-transition metal. The composite cathode active material may be included in a cathode, and the cathode may be included in a lithium battery.

The present invention pertains to composite cathodes suitable for use in an electrochemical cell, said cathodes comprising: (a) an electroactive sulfur-containing cathode material, wherein said electroactive sulfur-containing cathode material, in its oxidized state, comprises a polysulfide moiety of the formula —S_m—, wherein m is an integer equal to or greater than 3; and, (b) an electroactive transition metal chalcogenide composition, which encapsulates said electroactive sulfur-containing cathode material, and which retards the transport of anionic reduction products of said electroactive sulfur-containing cathode material, said electroactive transition metal chalcogenide composition comprising an electroactive transition metal chalcogenide having the formula M_j Y_k (OR)_l wherein: M is a transition metal; Y is the same or different at each occurrence and is oxygen, sulfur, or selenium; R is an organic group and is the same or different at each occurrence; j is an integer ranging from 1 to 12; k is a number ranging from 0 to 72; and l is a number ranging from 0 to 72; with the proviso that k and l cannot both be 0. The present invention also pertains to methods of making such composite cathodes, cells comprising such composite cathodes, and methods of making such cells.

The invention discloses a composite cathode material of a lithium ion battery and a preparation method thereof, and pertains to the technical field of nano-materials and chemical power source. The material is a composite of cathode material and a carbon nanotube or carbon nanofiber; the method of the invention comprises the step of adopting a chemical vapor deposition process for the in-situ growth of the carbon nanotube or the carbon nanofiber on the surface of the cathode material; the invention has simple process, energy conservation and consumption reduction and low production cost; and the composite cathode material is prepared by the steps that the carbon nanotube or the carbon nanofiber are directly erected on the surface of the cathode material to form a sea urchin type structure, and the carbon nanotube or the carbon nanofiber has good distribution uniformity, concentration degree and crystallinity on the surface of the cathode material; and the invention is characterized by high conductivity, high capacity, capability of rapid charge and discharge and the like in performance. The materials prepared by adopting the method of the invention can be widely applied in the new energy devices including lithium ion batteries, supercapacitors and the like, and can also be applied to catalyst carrier, absorbing materials, conductive materials and heat conducting materials and the like.

The invention discloses a silicon monoxide composite cathode material for a lithium ion battery, and a preparation method of the silicon monoxide composite cathode material, aiming at improving the cycle performance. The composite cathode material comprises the components by mass percent: 10-30% of composite particle material and 70-90% of natural graphite or artificial graphite, wherein the composite particle material is silicon monoxide covered by a carbon nano tube and an amorphous carbon coating layer. The method comprises the following steps of: forming the carbon nano tube and the amorphous carbon coating layer on the surface of silicon monoxide to obtain composite particles, and mixing the composite particles with the graphite. Compared with the prior art, the preparation method enables cracking carbon to be covered on the surfaces of silicon monoxide particles, so that the volume effect of the silicon monoxide particles can be effectively inhibited in the charge-discharge process of a battery, the cycle performance is good, the specific capacity is more than 500mAh/ g, and the capacity retention ratio is more than 85% after the circulation is carried out for 100 times; and the preparation method is simple in preparation technology, low in raw material cost and suitable for the cathode material for the high-capacity lithium ion battery.

The invention belongs to the technical field of nano-materials and chemical power sources and particularly provides a nano-Si or nano-Sn containing composite cathode material for a lithium ion battery and a preparation method thereof. The composite cathode material of the invention comprises the following components: cathode active substances, nano-Si or nano-Sn, and macromolecule polymers. The method taking the above components as raw materials comprises the following steps: firstly, preparing mixed solution; then, removing organic solvent; further coating the mixed solution with the macromolecule polymers; then, removing organic solvent; and finally, carrying out carbonization treatment to obtain the finished product. The invention has the advantages of fewer components, low cost, simple process and low energy consumption; and the composite cathode material prepared by the method of the invention has a core-shell structure and has the characteristics of high capacity, high stability and high capability of rapidly charging and discharging. Therefore, the composite cathode material of the invention is widely applicable to lithium ion batteries, super-capacitors and other components based on new energy resources and particularly applicable to lithium ion batteries for electric vehicles.

The invention relates to a method for preparing the composite cathode of lithium battery, wherein said cathode material is formed by silicon/copper/carbon; said silicon has nanometer porous structure; the nanometer silicon/alumina composite, nanometer silicon/alumina/copper composite, and nanometer silicon/alumina/copper/carbon composite, with high disperse degree, is obtained by high-energy grinding; then adding hydrochloric acid; removing alumina, and over alumina, to obtain said composite cathode. And the inventive method uses hydrochloric acid to remove the inactive alumina and over aluminum, to improve specific capacity of composite; and the treatment of hydrochloric acid makes the silicon with nanometer porous structure, to adsorb the volume change when embedding lithium, to buffer volume effect, improve the structure stability. And the reversible capacity of said cathode material can reach 580mAh .g-1; in the first 35 cycles, the average capacity damage of each cycle is 0.1%.

The invention discloses application of manganese dioxide for preparing a cathode of a microorganism fuel battery. The method comprises the following steps: the manganese dioxide is taken as a catalyst, the mixture of the catalyst, a conductive carbon material and a caking agent is coated on a conductive substrate to prepare the cathode of the microorganism fuel battery and a membrane composite cathode applied to the microorganism fuel battery. Compared with a non-catalytic electrode, MnO2 is taken as a cathode catalyst for remarkably increasing the reducing speed, reducing the polarization of the cathode and improving the energy output of the microorganism fuel battery; compared with the prior Pt catalyst, MnO2 has low price and wide source, and the microorganism fuel battery assembled by the catalyst of the cathode can operate stably for a long time and has high power output. The manganese dioxide for preparing the microorganism fuel battery electrode provides solid foundation for the commercial application of the microorganism fuel battery.