533results about How to "Improve Capacitive Performance" patented technology

Methods and apparatus for improving the sensing performance of a capacitive touch screen sensing device. The electrical potential of conductive structures proximate capacitive touch pads of the sensing device is altered to compensate for the effect of parasitic capacitance, based on external conditions such as water on the touch screen or an intervening user worn glove. The compensation for parasitic capacitance improves the signal to noise ratio and therefore the sensing performance of the device.

The invention provides a user selecting method of a multi-user MIMO communication system based on a codebook. An e Node B groups and selects dispatch users according to a PMI and a CQI feedback of users in a cell. The dispatch users are grouped according to the quasi orthogonality among codebook vectors expressed by the PMI. When the system runs, the e Node B ensures a signal path area which belong to each user according to the PMI feedback by a UE, selects a user with the maximal CQI to be taken as an optimum user of the area in the signal path subarea according to the CQI reported by the UE, computes the combined spectrum efficiency of each paired user group according to a previously set quasi orthogonality relationship, and selects one group of users with the largest combined spectrum efficiency to be taken as the current paired user group. The method can greatly simplify the computing complexity selected by the user in the multi-user MIMO communication system and can obtain the throughput performance near the optimum.

The invention discloses a lithium-sulfur battery cathode material and a preparation method thereof. The cathode material is formed by in-situ compositing of a mesoporous metal-organic framework and elemental sulfur. The mesoporous metal-organic frame is of a laminated pore structure consisting of a macro pore, a meso pore and a micro pore, wherein the pores are communicated with one another. The structure can adsorb more elemental sulfur and can simultaneously inhibit the dissolution of sulfur elementary substance and multi-sulfur compounds in electrolyte, so that the cycle performance of a lithium-sulfur battery is improved and high utilization rate of an active substance of the cathode material is kept. A sulfur and metal-organic framework material composite cathode material is prepared by a two-step process of low-temperature liquid phase composition and sulfur extraction, a composite material precursor with homogeneously dispersed high load sulfur content can be obtained through in-situ compositing at a low temperature with a liquid-phase preparation method, redundant sulfur on the surface of the precursor and in pore passages is extracted by an organic solvent, the aperture of the composite material can be further effectively adjusted and controlled, selective distribution of sulfur is realized, and the composite material with excellent electrochemical performance is obtained. By adopting the preparation method, the distribution of the sulfur in the composite material can be effectively improved, and the electrochemical performance of the composite material is optimized. Meanwhile, the preparation method is simple and is easy to perform industrially, and mass production is facilitated.

The invention discloses a preparation method of a lithium-ion battery with a conductive polymer coated positive electrode. The positive electrode sheet is a positive electrode slurry made of a positive electrode material, a conductive agent, a positive electrode binder, a conductive polymer or a conductive polymer monomer, and a solvent. The negative electrode sheet is composed of negative electrode material, thickener, negative electrode binder, and solvent mixed into negative electrode slurry and negative electrode current collector. The specific capacity of the battery is increased by 10-20% by adding a conductive polymer or a conductive polymer monomer to the slurry for coating. The invention effectively improves the performance of the prepared positive electrode material, and because the method is simple, the product cost is reduced, the process is simplified, and the method is suitable for large-scale production.

By using a composition comprising at least a vinylidene fluoride polymer containing a functional group and a polar polymer containing a hydroxyl group and / or a carbonyl group in the molecule as a binder for an electrode (positive electrode / or negative electrode) active material, the nonaqueous electrolysis can be maintained. The necessary high capacity of the liquid battery, and at the same time improve the stability of its performance and the safety of internal short circuit.

The invention discloses a transmitting antenna selection method for a generalized spatial modulation system under a correlated channel. The method comprises the following steps that 1) a receiving terminal performs ideal channel estimation to obtain an NR*MT MIMO (multiple-input and multiple-output) channel matrix H of the generalized spatial modulation system; 2) the receiving terminal calculates an L2 norm measure matrix Fh and a distance measure matrix D, which are used for the antenna selection method, according to the MIMO channel matrix H obtained in the step 1); 3) the receiving terminal selects an effective transmitting antenna set Phi according to the L2 norm measure matrix Fh and the distance measure matrix D, and informs a transmitting terminal of a selection result through a feedback channel; 4) the transmitting terminal performs generalized spatial modulation and transmission according to the effective transmitting antenna set Phi selected in the step 3). According to the method, characteristics of a spatial constellation set are changed by transmitting antenna selection in the generalized spatial modulation system, so that the problem that the bit error rate and capacity performance of the system are greatly reduced due to the fact of spatial constellation distinction difficulty caused by the correlation of transmitting antennae in an actual generalized spatial modulation system is solved.

Nitrided valve metals are described, such as nitrided tantalum and nitrided niobium. The nitrided valve metals preferably have improved flow properties, higher Scott Densities, and / or improved pore size distribution which leads to improved physical properties of the valve metal and improved electrical properties once the valve metal is formed into a capacitor anode. Processes for preparing a nitrided valve metal are further described and involve nitriding the valve metal at a sufficient temperature and pressure during a heat treatment that is prior to the deoxidation step. Capacitor anodes and other products incorporating the valve metals of the present invention are further described.

The invention discloses a silicon carbon composite material and a preparation method thereof. According to the preparation method, nano silicon powder particles are taken as a silicon substrate, a Si-C porous shell-core composite material is prepared, and the synergistic effect of silicon and carbon can be fully developed; the silicon material is high in electrochemical capacity, the carbon material is high in conductivity, and the flexible carbon material can be used for absorbing stress and buffering a volume effect of the silicon; meanwhile, the stable and firm shell-core structure can be used for maintaining the material stability; the porous structure can be used for increasing the contact structure of the silicon particles and an electrolyte and improving the compatibility of the silicon particles and the electrolyte; and the three-layer shell-core structure material is dispersed in a graphene material, the conductivity of the material can be further improved, and the capacity performance and the cycle life of an electrode material are improved.

The invention discloses a method for preparing a stannic oxide battery anode material on a carbon nano tube by using an electro-deposition process. The method comprises the steps of: making electro-deposition solution, treating the solution with water bath, preparing the carbon nano tube pole piece, pressing on a foam nickel base, putting the base carrying the carbon nano tube pole piece into the electro-deposition solution so as to perform vacuum treatment, and then perform the electro-deposition treatment under a constant current on the vacuumized pole piece so as to acquire the battery anode material on the carbon nano tube carrying the stannic oxide. The battery anode material prepared by using the method has higher power property and has a quality specific capacity kept between 350 and 450 F / g under a high scanning speed of 200 mV / s. The material applied in a super capacitor has higher volumetric properties, excellent cycling stability and long cycling life, first discharging specific capacity ranged between 410 and 588 F / g under a constant current density of 15 A / g, cycling times more than 5000 times and specific capacity retention rate ranged between 90 to 95 percent.

The invention provides a method for preparing a graphene / nanocarbon particle composite. The method comprises the steps that (1) graphite is oxidized to prepare oxidized graphene, and the acquired oxidized graphene is added to water to prepare suspension liquid; (2) nanocarbon particles are added to water solution with a surface active agent to acquire suspension liquid of the nanocarbon particles; (3) the suspension liquid of the oxidized graphene is mixed with the suspension liquid of the nanocarbon particles, and then mixed suspension liquid is acquired; (4) the uniformly mixed suspension liquid is spray-dried to acquire powder; (5) reduction treatment is conducted on the powder acquired in the step (4), or the powder acquired in the step (4) is placed in an inert gas atmosphere, thermal pretreatment is conducted on the powder acquired in the step (4), then reduction reaction is conducted in a reducing atmosphere, and eventually the graphene composite loading the nanocarbon particles is prepared. The invention further relates to the graphene / nanocarbon particle composite acquired by the method and application of the graphene / nanocarbon particle composite being used as materials of supercapacitors, catalyst carriers and infrared optical materials.

The invention provides the channel estimating method used for pilot frequency supplementary estimating system, the corresponding emitting method, the corresponding receiving method and the improved communication system structure. The invention sets the upper limit of information symbol transmitting speed of each group at the emitting end as the lower bound of mutual information between the input operation and the output operation, which the system can reach when the receiving end implements the relative detection for the information symbol of each group. Primarily, the receiving end utilizes the known pilot frequency symbol to implement channel estimation. The channel parameter which is obtained is implemented with initial estimation value. The initial estimation value is utilized to implement the relative detection for information symbol of the first group, and then the information symbol of the group, which is judged, is taken as equivalent pilot frequency symbol and estimates the channel again together with the known pilot frequency. The new channel parameter estimation value is utilized to implement the relative detection for the information symbol of the next group, which is received. The iteration is implemented and the channel is estimated. With the increase of equivalent pilot frequency energy, the estimation difference of the channel is reduced; therefore, the capacity performance of the system is improved.

The invention relates to covalence organic frame / graphene composite materials and a preparing method. According to the materials, amination graphene is used as a base body, 1,3,5-benzenetricarboxaldehyde, p-phenylenediamine and catalyst acetic acid are added into graphene turbid liquid according to a certain ratio for stirring, the liquid is placed in a reactor to be heated for certain time, and the covalence organic frame / graphene composite materials can be obtained. The technology is simple, the prepared composite materials have the advantages of being high in specific capacitance and stable in performance, and the materials can be used as electrode materials of a novel energy storing system used by an electric car.

The invention discloses a recycling method for a graphite anode material from a waste lithium-ion battery, and belongs to the technical field of recovering of materials from the waste lithium-ion battery. According to the main points of the technical scheme, the method comprises the following steps: carrying out soaking pretreatment on the graphite material recovered from the waste lithium-ion battery; carrying out ball-mill mixing on pre-calcined and separated graphite powder and a ferrous oxalate or zinc oxalate or ferrous oxalate and zinc oxalate mixture evenly; and finally preparing the battery-grade graphite anode material through high-temperature treatment. The graphite anode material prepared by the method has excellent electrochemical activity and cyclic reversibility; the discharge capacity at 0.2C reaches over 400mAh / g; and the capacity retention rate after 50 cycles is greater than 98.0%. The recycling method can efficiently recover the graphite anode material from the waste lithium-ion battery, further improves the electrical property and achieves recycling of the graphite anode material.

The invention discloses a zinc oxide (ZnO) / reduced graphene oxide / polypyrrole (ZnO / RGO / PPy) ternary composite material, which belongs to the technical field of composite material. The ZnO / RGO / PPy ternary composite material is prepared by a two-step method, including preparing a uniformly-dispersed binary composite material ZnO / reduced graphene oxide (ZnO / RGO), and polymerizing pyrrole (Py) monomer by chemical oxidation method by using the binary composite material as a template to obtain the ZnO / RGO / PPy ternary composite material. The ZnO / RGO / PPy ternary composite material prepared by the invention has both the electric double layer capacitance characteristics of RGO and pseudocapacitor energy storage characteristics of ZnO and Ppy, so that the composite material can show high electrochemical capacitance behavior, excellent rate capability, good circulation stability, and has high energy densigh and power density, , and can be used as the electrode material of a super capacitor.

The invention relates to a graphene hollow nano fiber and a preparation method thereof. The external diameter of the graphene hollow nano fiber is 7-700nm, the internal diameter is 6-698nm, the length-diameter ratio is 20:1-2000:1, and the specific area is 300-2600 m<2> / g. The preparation method comprises the following steps: by using an inorganic fiber as a template, heating to 400-1000 DEG C in a carrier gas, introducing a carbon source, and decomposing at the same temperature to directly form the graphene hollow fiber or form a carbon-inorganic template composition fiber; and cooling the composition fiber, treating with acid or alkali, filtering, washing and drying. The preparation method is simple; and the product has the advantages of high purity, complete structure and high mechanical strength, and is suitable to be used as a separation or adsorbing material, an electrode material for electrochemical energy storage or a conducting agent.

Nitrided valve metals are described, such as nitrided tantalum and nitrided niobium. The nitrided valve metals preferably have improved flow properties, higher Scott Densities, and / or improved pore size distribution which leads to improved physical properties of the valve metal and improved electrical properties once the valve metal is formed into a capacitor anode. Processes for preparing a nitrided valve metal are further described and involve nitriding the valve metal at a sufficient temperature and pressure during a heat treatment that is prior to the deoxidation step. Capacitor anodes and other products incorporating the valve metals of the present invention are further described.

The invention belongs to the technical field of nanomaterial, and specifically discloses a nickel sulfide nanoparticle / nitrogen-doped fiber-based carbon aerogel composite material and a preparation method therefor. The composite material is prepared by the steps of adopting nickel salt and a sulfur source, and performing in-situ growth of the nickel sulfide nanoparticles on the nitrogen-doped cellulose-based carbon aerogel; the raw materials comprise a biomass material rich in fibers, nickel salt, thiocarbamide, dopamine and aniline monomer; the preparation process comprises the steps of preparing a poly-dopamine-coated fiber-based biomass material or a polyaniline-coated cellulose-based biomass material through a one-step polymerization method; preparing the nitrogen-doped cellulose-based carbon aerogel through a high temperature carbonization method; and performing in-situ growth of the nickel sulfide nanoparticles on the surface of the nitrogen-doped fiber-based carbon aerogel by adopting a one-step solvothermal method. The composite material prepared by the invention has the uniform distribution characteristic of the nickel sulfide nanoparticles on the nitrogen-doped fiber-based carbon aerogel, so that the composite material can be used as the ideal supercapacitor electrode material.

The invention belongs to the technical field of preparation of supercapacitor materials, and relates to a preparation method of a nickel cobaltate / nickel hydroxide / foamed nickel supercapacitor electrode material. According to the method, the nickel cobaltate is enabled to grow on the foamed nickel in situ, and then the nickel hydroxide is electrochemically deposited on a nickel cobaltate / foamed nickel sample. Meanwhile, the high specific surface area of the sample is maintained. During the rapid charging and discharging process, the nickel hydroxide / nickel cobaltate / foamed nickel composite electrode material is maintained to be high in cycling performance and high in capacitance performance. The nickel hydroxide / nickel cobaltate / foamed nickel electrode material can be directly subjected toelectrochemical test, and is different from the traditional sample dropping test.

The invention belongs to the technical field of super capacitor material preparation and relates to a cobalt sulfide / nickel hydroxide / foam nickel super capacitor electrode material and a preparation method thereof. Cobalt sulfide is grown on foamed nickel, and nickel hydroxide is electrochemically deposited on the surface of the cobalt sulfide to form a composite material of cobalt sulfide / nickelhydroxide / foam nickel. According to the super capacitor electrode material and the preparation method, a transition metal hydroxide is loaded on a surface of the cobalt sulfide with a high specific surface area and good electrical conductivity through a composite mode, and the cobalt sulfide / nickel hydroxide / foam nickel composite material is prepared. Through the synergistic effect between components of the composite material, the components promote virtues and avoid shortages, and at the same time, combined with a high cycle life, high power density and high stability of a double-electric-layer capacitor and a high specific capacitance of a pseudo capacitor, the overall performance of the super capacitor is improved.

The invention discloses a making method of composite electrode material of conductive macromolecular and carbon nanometer pipe, which is characterized by the following: dispersing normal surface activator of carbon nanometer pipe in the polymeric solution; improving the specific capacity of composite material as well as coordinating effect; adsorbing bulk compaction and bulking at discharge time through hollow structure of carbon nanometer pipe; improving conductivity and reducing resistance of composite material.

The invention discloses a resource distribution method for maximizing the energy efficiency of a system under the premise that the minimum transmission rate of the system is met in the multi-relay OFDM network. In the relay network, one sub-carrier wave can be allocated to a source node and multiple relay nodes, and therefore a space diversity can be provided for the system. The optimal model including sub-carrier pairing and power distribution to maximize the power efficiency of the system is a typical nonlinear mixed integer programming problem, and the problem usually has great computation complexity. According to the resource distribution method, the optimal solution is obtained by defining the equivalent channel gain and simplifying the original complex optimization problem into a quasi concave programming problem through the Dinkelbach method, the Hungarian algorithm and the subgradient algorithm, and the computing complexity is greatly lowered.

The present invention is directed toward a breadcrumb continuous processing line and process capable of producing multiple types of breadcrumbs, namely American style breadcrumbs, Japanese style breadcrumbs and cracker meal crumbs. Each type of bread crumbs has different characteristics including the thickness of the dough sheet the different baking requirements. The breadcrumb processing line, and the oven therein is capable of being adjusted to process of the bread dough sheet in the manner necessary to produce the type of breadcrumb desired at any given time on a single processing line.

The invention discloses a carbon compound cathode material for an ultracapacitor battery, comprising a nuclear layer and a shell layer, wherein the shell layer accounts for the total weight of 10-40 percent; the nuclear layer is made of graphite materials subjected to surface nanometer treatment; and the shell layer is made of a porous carbon material. The surface nanometer treatment of the nuclear layer is to form a nano carbon fiber, a cabon nanotube or a nano hole on the surface of natural graphite, artificial graphite or an in intermediate phase carbon microsphere material in situ; and the porous carbon material comprises a three-dimensional structure that millipores are distributed on a carbon organism. Metal elements are doped in the shell layer. The component formula is reasonable; the prepared material has the nuclear and shell structures in which the metal elements are doped; meanwhile, the invention has favorable characteristics of energy accumulation by using double electric layers and lithium ion stripping / embedding, can effectively improve the high multiplying power and the power density of a lithium ion battery, meets the double requirements of the ultracapacitor battery on energy accumulation by using the lithium ion and double electric layers of the cathode material, can be used as a cathode of a high-performance lithium ion battery, and has favorable high multiplying power charge-discharge performances and industrial prospect.

The invention discloses a graphite / silicon@carbon core-shell structure composite spherical cathode material and a preparation method thereof. By means of the material, the volume expansion effect of silicon in the lithium de-intercalation process can be inhibited, and a high-capacity lithium iron battery silicon / carbon composite cathode material is obtained. By means of the technical scheme, a spherical graphite / silicon framework precursor serves as the core of the composite cathode material, and an amorphous pyrolytic carbon or graphite-like carbon material wrapping layer serves as the shell; nanometer or micrometer silicon is embedded in flake graphite cracks to form a graphite framework, the volume expansion effect of silicon in the lithium de-intercalation process is inhibited through the mechanical characteristics of the graphite framework, then a spherical framework is formed by mixing and granulating 3-20 wt% of nanometer or micrometer silicon, 50-80 wt% of flake graphite and 10-40 wt% of amorphous pyrolytic carbon or graphite-like carbon, and an amorphous pyrolytic carbon or graphite-like carbon spherical composite conductive carbon net structure wrapping a graphite / silicon surface is formed.

The invention provides a silicon-carbon composite material of a closed cage structure and a preparation method of the silicon-carbon composite material of the closed cage structure. The silicon-carboncomposite material of the closed cage structure is a hollow filled structure material in a closed cage form; the core of the hollow filled structure material is a silicon material-filled porous carbon material; the porous carbon material is filled with a silicon material; the silicon material has the void content of 50-95% in the porous carbon material; and a carbon material coats the outside ofthe silicon material-filled porous carbon material and the specific component of the carbon material is (SiOx)yC, wherein x is smaller than or equal to 2 and greater than or equal to 0 and y is smaller than or equal to 1 and greater than 0. When the silicon-carbon composite material of the closed cage structure is used as a negative electrode of a battery, contact of the silicon material and an electrolyte is isolated, the life of the battery is prolonged and the capacity performance and the cycle performance of the battery are improved.

The invention discloses a lithium ion battery cathode material with a variable slope concentration gradient doping structure and a synthesis method thereof. For solving the problems of capacity fadingand rate performance degradation which are brought by the conventional doping method, an element with a variable slope concentration gradient structure is doped, thereby obtaining the lithium ion battery cathode material with the concentration of a doping element continuously changed from the center of a material particle to the surface of the material particle; and change rate is gradually increased from inside to outside, so that the concentration of the doped element inside the material is slowly changed, the concentration of the doped element on the surface of the material is rapidly changed, and change of the concentration of the doped element is mainly concentrated on a surface layer. The method improves stability of the internal structure and the surface of the material while sideeffect is not introduced, the problems such as phase change of the material, volume change and dissolution of transition metal elements in a charge-discharge cycle process are reduced, cycle life of the material is greatly prolonged, and safety performance of the material is greatly improved.

The invention discloses a high-performance silicon monoxide / amorphous carbon / graphite composite negative electrode material. The high-performance silicon monoxide / amorphous carbon / graphite composite negative electrode material comprises the following components in parts by weight: 5-7 parts of silicon monoxide, 1-2 parts of carbohydrate and 1-4 parts of natural flake graphite. The preparation method of the composite negative electrode material comprises the following steps of: mixing the materials; carrying out high-energy ball milling and high-temperature pyrolysis; and grinding and sieving to obtain the composite material. The composite negative electrode material is excellent in cycle performance and capacity performance, so that a certain feasibility choice is provided for practicability of the SiO negative electrode material. Moreover, the preparation method is simple to operate, environment-friendly, pollution-free and easy to popularize.

The present invention relates to a lithium iron phosphate electrode material having a three-dimensional hierarchical structure, and a preparation method thereof. The preparation method comprises: 1) sequentially adding a surfactant and a phosphorus source compound to a solvent, and uniformly stirring for use; 2) dispersing an iron source compound in a solvent, and uniformly stirring for use; 3) dispersing a lithium source compound in a solvent, and uniformly stirring for use; 4) mixing and stirring the solutions or suspensions of the phosphorus source compound, the iron source compound and the lithium source compound, and loading into a reaction kettle; 5) carrying out a reaction under a hydrothermal or solvothermal condition, and washing and drying the obtained product to obtain lithium iron phosphate with various hierarchical structures; and 6) calcining to obtain the hierarchical structure lithium iron phosphate material having high crystallinity. According to the present invention, the preparation method is the wet chemical method for preparing the lithium ion battery positive electrode material lithium iron phosphate (LiFePO4) by adopting the precursor directly obtained through the hydrothermal or solvothermal reaction, and the surface activity structure-oriented method is adopted to design and construct the electrode material having high specific surface area and excellent electrochemical property.

The invention provides a method for preparing a grapheme / carbon composite material. The method comprises steps of mixing and reacting aniline monomer, an oxidant and mesomorphic grapheme oxide, obtaining a grapheme oxide / polyaniline compound, mixing and reacting the obtained grapheme oxide / polyaniline compound and an activating agent and obtaining the grapheme / carbon composite material. The aniline monomer and the mesomorphic grapheme oxide serve as raw materials and are mixed completely, polyaniline is produced among layers of grapheme oxide, the agglomeration phenomenon during the grapheme activating process can be avoided effectively, the polyaniline attached to grapheme surfaces forms a multi-hole carbon material through the activating treatment, and the prepared grapheme / carbon composite material has good capacitive and cycle performance.

The invention relates to an additive and a solvent of a lithium secondary battery electrolyte, belonging to the field of lithium battery materials. The structural formula of the additive is shown as the specification, wherein R represents an alkyl group of which the carbon atom number is 1-20 or an alkyl group of which the carbon atom number is 1-20 and hydrogen is replaced by halogen atoms; R' is one selected from the alkyl group of which the carbon atom number is 1-20, the alkyl group of which the carbon atom number is 1-20 and the hydrogen is replaced by the halogen atoms, an alcoxyl ethylof which the carbon atom number is 1-20, an alcoxyl ethyl of which the carbon atom number is 1-20 and hydrogen is replaced by halogen atoms, an aryl group of which the carbon atom number is 6-30 or an aryl group of which the carbon atom number is 6-30 and hydrogen is replaced by halogen atoms; the mass percent of the additive is 1-50%; and preferably the solvent is a solvent which contains isocyanate compounds with the mass percent of 1-50%. The electrolyte containing the additive and the solvent is high in conductivity at a low temperature, can form an SEI (solid electrolyte interface) film on the anode surface of the lithium secondary battery and is high in safety and oxygenolysis potential.