12857results about How to "Improve cycle performance" patented technology

A negative electrode material comprising an active material and 1-20 wt % of a polyimide resin binder is suitable for use in non-aqueous electrolyte secondary batteries. The active material comprises silicon oxide particles and 1-50 wt % of silicon particles. The negative electrode exhibits improved cycle performance while maintaining the high battery capacity and low volume expansion of silicon oxide. The non-aqueous electrolyte secondary battery has a high initial efficiency and maintains improved performance and efficiency over repeated charge / discharge cycles by virtue of mitigated volumetric changes during charge / discharge cycles.

The negative electrode for a non-aqueous electrolyte secondary battery of the present invention includes a conductive porous substrate, and a conductive material and an active material filled in pores of the porous substrate. The active material contains at least one of a metal element and a semi-metal element capable of reversibly absorbing and desorbing lithium.

Silicon composite particles are prepared by sintering primary fine particles of silicon, silicon alloy or silicon oxide together with an organosilicon compound. Sintering of the organosilicon compound results in a silicon-base inorganic compound which serves as a binder. Each particle has the structure that silicon or silicon alloy fine particles are dispersed in the silicon-base inorganic compound binder, and voids are present within the particle.

This invention provides a film comprising a cross-linked polymer having an oxyalkylene group or a cross-linked polymer having an oxyalkylene group through a urethane bond, as a constituent component, a production method of the film, and an electrochemical apparatus using the film as a separator. The film for separator of an electrochemical apparatus can be easily and uniformly processed, can include an electrolytic solution, exhibits good film thickness and ensures excellent safety and reliability. The electrochemical apparatus is free of leakage of the solution.

To provide a working medium for heat cycle, of which combustibility is suppressed, which has less influence over the ozone layer, which has less influence over global warming and which provides a heat cycle system excellent in the cycle performance (capacity), and a heat cycle system, of which the safety is secured, and which is excellent in the cycle performance (capacity).A working medium for heat cycle comprising 1,1,2-trifluoroethylene is employed for a heat cycle system (such as a Rankine cycle system, a heat pump cycle system, a refrigerating cycle system 10 or a heat transport system).

The invention relates to a silicon-carbon composite negative electrode material and a preparation method thereof. The silicon-carbon composite negative electrode material successively comprises nano silicon / graphite particles, a first carbon coating layer and an organic cracking carbon layer from inside to outside. The nano silicon / graphite particles are globular or globular-like composite particles formed by employing graphite as an inner core of a volume expansion buffer substrate and coating a nano silicon particle layer; the first carbon coating layer comprises carbon nanotubes and / or amorphous carbon, the carbon nanotubes and / or amorphous carbon are interspersed in a gap network formed by gaps of the nano silicon particles and / or are coated outside the nano silicon particle layer, so that the nano silicon is tightly wrapped between the carbon nanotubes and / or between the carbon nanotubes and the graphite substrate, and besides, the material ion conductivity is effectively enhanced; the organic cracking carbon layer is an outermost coating layer of the silicon-carbon composite negative electrode material. The silicon-carbon composite negative electrode material has excellent cycle performance, excellent multiplying power charging and discharging performance and lower volume expansion effect.

The invention provides a silicon-carbon composite anode material, which comprises a nuclear shell structure and a support substrate, wherein particle size of the silicon-carbon composite anode material is 1-200 micrometers, and porous carbon serving as the support substrate is obtained through decomposition of biomass materials. The invention further provides a preparing method of the silicon-carbon composite anode material, which includes the following steps: 1 reaming the biomass materials in physical activation or chemical activation mode to prepare the porous carbon, or preparing small molecular organics serving as a precursor of the porous carbon in hydrolyzing mode; 2 mixing silica particles and the obtained porous carbon or the precursor of the porous carbon in solution and performing ultrasonic treatment; 3 evaporating the solution mixture to dry so as to obtain solid-state powder; and 4 drying the solid-state powder, and performing thermal treatment, crushing and sieving on the solid-state powder to obtain the silicon-carbon composite anode material. The silicon-carbon composite anode material and the preparing method thereof are simple in process, short in flow path, easy to operate and low in cost, and lithium ion batteries manufactured by the silicon-carbon composite anode material are suitable for various mobile electronic equipment or devices driven by mobile energy.

The present invention relates to a preparation method for a nickel-manganese-cobalt anode material of a lithium ion battery. According to the present invention, in the presence of nitrogen atmosphere, a mixed solution containing nickel iron, manganese iron and cobalt ion reacts with a precipitating agent, then processes of aging, washing, drying and the like are performed to obtain a nickel-manganese-cobalt hydroxide precursor, the synthesized precursor material has spherical morphology, ideal particle size distribution and high tap density; the precursor, a lithium compound and a doped compound are mixed, then the sintering processing is performed for twice to prepare the nickel-manganese-cobalt three-element composite anode material. The method has characteristics of simple synthesis process, easy process controlling, low energy consumption, high efficiency and low cost, and is applicable for the industrial production; the prepared precursor material has characteristics of spherical morphology, uniform particle distribution and high tap density; the discharge capacity of the battery is improved through doping the metals; the cycle performance of the battery is stable.

Provided is a lithium ion conductive composite electrolyte that can prevent leakage of electrolyte solution, and that have excellent cycle performance and lithium ion conductivity, and a lithium ion secondary battery. A lithium ion conductive composite electrolyte 1 is formed so that a lithium ion conductive polymer gel electrolyte is held in a porous body 2 formed from lithium ion conductive inorganic solid electrolyte particles and an organic polymer. The lithium ion conductive inorganic solid electrolyte particles are formed from a composite metal oxide that has a garnet structure, and is represented by the chemical formula Li7−yLa3−xAxZr2−yMyO12 (wherein 0≦x 3, 0≦y≦2, A is one of Y, Nd, Sm, and Gd, and M is Nb or Ta). A lithium ion secondary battery 11 includes the lithium ion conductive composite electrolyte 1 between a positive electrode 12 and a negative electrode 13.

Disclosed in the invention are a silicon-carbon composite anode material for lithium ion batteries and a preparation method thereof The material consists of a porous silicon substrate and a carbon coating layer. The preparation method of the material comprises preparing a porous silicon substrate and a carbon coating layer. The silicon-carbon composite anode material for lithium ion batteries has the advantages of high reversible capacity, good cycle performance and good rate performance. The material respectively shows reversible capacities of 1,556 mAh, 1,290 mAh, 877 mAh and 474 mAh / g at 0.2 C, 1 C, 4 C and 15 C rates; the specific capacity remains above 1,500 mAh after 40 cycles at the rate of 0.2 C and the reversible capacity retention rate is up to 90 percent.

The invention relates to a lithium ion battery silicon-based composite anode material, a preparation method of the lithium ion battery silicon-based composite anode material, and a battery. The lithium ion battery silicon-based composite anode material adopts an embedded composite core-shell structure, a core has a structure formed by embedding nano silicon particles into a gap of an inner layer of hollowed graphite, and a shell is made from a non-graphite carbon material. According to the silicon-based composite anode material, mechanical grinding, mechanical fusing, isotropic compression processing and carbon coating technologies are combined, so that the nano silicon particles can be successfully embedded into the inner layer of the graphite and the surfaces of graphite particles are uniformly coated; the high-performance silicon-based composite anode material is obtained and is excellent in cycle performance (the 300-times cycle capacity retention ratio is more than 90%) and high in first efficiency (more than 90%); in addition, the silicon-based composite anode material is high in specific energy and compaction density, and can meet the requirements of a high-power density lithium ion battery; the preparation process is simple, the raw material cost is low, and the environment is protected.

A negative electrode material comprises a conductive powder of particles of a lithium ion-occluding and releasing material coated on their surface with a graphite coating. The graphite coating, on Raman spectroscopy analysis, develops broad peaks having an intensity I1330 and I1580 at 1330 cm−1 and 1580 cm−1 Raman shift, an intensity ratio I1330 / I1580 being 1.5<I1330 / I1580<3.0. Using the negative electrode material, a lithium ion secondary battery having a high capacity and improved cycle performance can be manufactured.

A method for making sulfur-graphene composite material is disclosed. In the method, a dispersed solution including a solvent and a plurality of graphene sheets dispersed in the solvent is provided. A sulfur-source chemical compound is dissolved into the dispersed solution to form a mixture. A reactant, according to the sulfur-source chemical compound, is introduced to the mixture. Elemental sulfur is produced on a surface of the plurality of graphene sheets due to a redox reaction between the sulfur-source chemical compound and the reactant, to achieve the sulfur-graphene composite material. The sulfur-graphene composite material is separated from the solvent.

A non-aqueous electrolyte secondary battery negative electrode material is provided wherein a negative electrode active material containing a lithium ion-occluding and releasing material which has been treated with an organosilicon base surface treating agent is surface coated with a conductive coating. Using the negative electrode material, a lithium ion secondary battery having a high capacity and improved cycle performance is obtainable.

This invention relates to a kind of silicon&carbon composite material with a spherical appearance and core-shell structure in spherical particles with a mean diameter of 1.2~53 micron and a 'core-shell' structure, there are silicon particles 5~50wt% and carbon particles 50~95wt%, the core of which is spherical carbon particles with a mean diameter of 1~45 micron. The carbon particles are the mixture of one, two or three kinds of mesophase carbon graphite balls, hard carbon balls and spherical graphite ball. The thickness of the shell is 0.1~4 microns composed of carbon and silicon grains with the average size of 10 nm~4 micron. The carbon&silicon composite materials are achieved through thermal decomposition and chemical vapor deposition after the spherical carbon particles are coated with silicon and carbon composite ultrafine silica slurry.

The present invention is characterized by obtaining a high charge / discharge capacity upon high rate charging / discharging in a hybrid capacitor having characteristics of both an electric double layer capacitor and a lithium-ion secondary battery. Specifically, the present invention is a capacitor comprising: a positive electrode 1 composed of a polarizable electrode containing activated carbon; a negative electrode 2 containing as an anode active material a carbon material capable of inserting / extracting lithium ion; and a nonaqueous electrolyte containing lithium ion, wherein a charge cutoff potential for the negative electrode 2 is within the range of 0.15 to 0.25 V (vs. Li / Li+).

The invention relates to a novel carbon-sulfur compound for an anode material of a lithium-sulfur battery and a preparation method thereof. Sulfur is filled into a nano and micron hole of a matrix in an elementary substance way by taking a macroporous carbon material with high pore volume, electrical conductivity and specific surface area as the matrix, and the sulfur and carbon can also carry out combination reaction so as to prepare the novel carbon-sulfur compound of which the sulfur exists in one or more chemical states in a carbon material. The novel carbon-sulfur compound used as the anode material of the lithium-sulfur battery has the advantages that the high pore volume has large contained sulfur contents and can ensure high electric capacity; the small granularity of the sulfur can reduce a conductive distance between ions and electrons and increase the utilization ratio of the sulfur; and the adsorption characteristics of the high specific surface of the carbon material can inhibit a discharging intermediate product from dissolving and moving towards a cathode, reduce the self discharge, prevent a nonconductive discharging product, namely lithium sulfide from largely accumulating outside carbon particles and reduce internal resistance, therefore, the material can improve the specific energy, the specific power and the cycle performance of the lithium-sulfur battery.

The invention discloses a lithium ion battery and a positive material, the positive material possesses a core-shell structure, the material of a core layer is at least one of lithium cobaltate, a ternary material and a lithium manganese material, the material of a shell layer is lithium nickel manganese spinel. The preparation method comprises the following steps: preparing the sol shell layer material, then adding the core layer material in the sol, stirring, drying and calcining to prepare the lithium ion battery positive material with the core-shell structure. In addition, the invention also discloses the lithium ion battery prepared by the positive material with the core-shell structure, the end of charge voltage is 4.3-4.7V(vs. Li), the lithium ion battery has excellent charge and discharge cycling performance and high temperature storage performance under high voltage.

The invention discloses a graphene / molybdenum disulfide (MoS2) compound nano material lithium ion battery electrode and a preparation method thereof. The electrode comprises the following components in percentage by mass: 75 to 85 percent of compound nano material serving as an active substance, of a graphene nano slice and MoS2, and 5 to 10 percent of acetylene black and 10 percent of polyvinylidene fluoride; and the mass ratio of the graphene nano slice to the MoS2 nano material in the compound nano material active substance is (1 to 1)-(4 to 1). The preparation method of the electrode comprises the following steps of: preparing an oxidized graphite nano slice by using graphite as a raw material by a chemical oxidization method; synthesizing by a one-step hydrothermal in-situ reduction method in the presence of the oxidized graphite nano slice to obtain a graphene nano slice / MoS2 compound nano material; and finally, preparing the electrode by using the graphene nano slice / MoS2 compound nano material as the active substance. The electrode has high electrochemical lithium storage reversible capacity and cyclic stabilization performance, and can be widely applied to new generation lithium ion batteries.

The invention belongs to the technical field of lithium ion batteries, in particular to a method for supplementing lithium for a negative electrode of a lithium ion battery. The method comprises the following steps: spraying or dripping an organic lithium solution on a surface of a negative electrode in an inert atmosphere, so that lithium ions in the organic lithium solution are reverted to metal lithium which is embedded into the negative electrode; and drying the negative electrode. Compared with the prior art, in the method, the organic lithium solution is sprayed or dipped on the surface of the negative electrode evenly so as to realize lithium supplementation in a wet process, thereby effectively avoiding metallic lithium powders floating in the air in a dry process to ensure safe production; and the whole process is simple, the cost is lower, the amount of the lithium supplementation can be controlled accurately through the amount and the time by spraying or dripping the organic lithium solution so as to supplement the lithium evenly, thereby preventing lithium precipitation and deformation of the negative electrode and improving the initial efficiency of the battery. Therefore, the the energy density of the battery is improved. Additionally, the invention further discloses another method for supplementing the lithium for the negative electrode of the lithium ion battery.

A battery containing a first electrode and a second electrode, and an electrolyte for transferring ionic charge-carriers there between, wherein the first electrode contains a first electrode active material represented by the formula A2eM4kM5mM6nM7oOg, and at least one second electrode active material selected from the group consisting of active materials represented by the formula A1aM1b(XY4)cZd, active materials represented by the formula A3hMniO4, and mixtures thereof.

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.

A negative electrode material for nonaqueous electrolyte secondary batteries comprises composite particles which are prepared by coating surfaces of particles having silicon nano-particles dispersed in silicon oxide with a carbon coating, and etching the coated particles in an acidic atmosphere. The silicon nano-particles have a size of 1-100 nm. The composite particles contain oxygen and silicon in a molar ratio: O<O / Si<1.0. Using the negative electrode material, a lithium ion secondary battery can be fabricated which features a high 1st cycle charge / discharge efficiency, a high capacity, and improved cycle performance.

PCT No. PCT / JP95 / 01897 Sec. 371 Date Mar. 19, 1997 Sec. 102(e) Date Mar. 19, 1997 PCT Filed Sep. 20, 1995A method of straightening a wire rod of titanium or titanium alloy wherein the rod is hot-straightened to a straight rod at the straightening temperature T and elongation epsilon satisfying the expression (1) or (2). The method includes hot rolling a titanium billet of beta titanium alloy, ( alpha + beta ) titanium alloy or a near alpha titanium alloy into a wire rod, winding the hot rolled wire rod into a coil, cold drawing the wire rod, cutting the wire rod to obtain a bent wire rod, heating the bent wire rod to a straightening temperature T while both end portions of the bent wire rod are fixed, applying a predetermined elongation epsilon to the wire rod, maintaining a straightening temperature T, hot-straightening the wire in accordance with the expression (2) epsilon (T-400)> / =400(1) epsilon (T-500)> / =200(2) and cooling the wire rod while applying tension. The method is suitable for preparing a straight rod for use in an engine valve.

The invention provides a high nickel anode material, which comprises a base body and a coating layer, wherein aluminum (Al), titanium (Ti), magnesium (Mg), zirconium (Zr), calcium (Ca), zinc (Zn), boron (B), fluorine (F), vanadium (V), strontium (Sr), barium (Ba), yttrium (Y), neodymium (Nd), caesium (Cs), tungsten (W), molybdenum (Mo), ruthenium (Ru), rubidium (Rb) or lanthanides are mingled on the surface of the base body, the coating layer is coated on the surface of the base body, and comprises one or more of the magnesium, the titanium, the zirconium, the fluorine, the boron, the aluminum and phosphate. The elements are mingled on the surface of the base body of the high nickel anode material, the mingled elements can stabilize a surface crystal structure of the base body, remit damage of washing liquid to a material surface structure of the base body, and enable capacity and cycle performance of a lithium ion battery which is prepared through the high nickel anode material to be better. Furthermore, the high nickel anode material is provided with the coating layer, and the coating layer enables the high nickel anode material to separate from an electrolyte part, and improves electrochemical stability and safety of the high nickel anode material. The invention further provides a method for preparing the high nickel anode material and a lithium ion battery.

The invention discloses a preparation method of a nitrogen-doped porous-structure carbon material and belongs to the technical field of inorganic material preparation. The preparation method utilizes a micromolecular carbon-containing compound as a raw material and comprises the following steps of based on the weight of the raw material, adding 0-400wt% of an inorganic base, 0-400wt% of an organic nitrogen-containing compound and 0-50wt% of a metal or metal oxide or inorganic metal salt into the raw material, carrying out uniform dispersion, and carrying out a reaction process in an inert gas protective atmosphere at a temperature of 400-900 DEG C for 0.5-12h so that the nitrogen-doped porous-structure carbon material having micropores, mesopores and macropores is obtained. The preparation method has simple processes, can be controlled easily, and realizes one-step combination of porous structure, functionalization nitrogen doping and metal particle modification. The nitrogen-doped porous-structure carbon material having high nitrogen content has a large capacitance value and good cycle performances, can be used as an oxygen reduction reaction catalyst having high activity, high selectivity and high stability and has a very large application prospect.

A surface mount fuse includes a plurality of substrate / arc suppressive layers, a plurality of fusible elements positioned between the substrate / arc suppressive layers and terminations connected to the ends of the fusible elements, such that the fusible elements are electrically connected in parallel. The surface mount fuse has greater amperage and voltage ratings than similarly sized conventional surface mount fuses. Additionally, the surface mount fuse has increased interrupt breaking capacity and superior mechanical properties.

The invention has a grain structure with an outer shell and several inner cores. The grain size is from 100 nanometers to 100 microns. The inner cores are compound grain that includes active substance and conducting additive. The outer shell is a carbon layer. The active substance takes 20-95wt% of total cathode active material, and is mixture of one or several transition metallic compound selected from silicon and lithium storage whose thermodynamic equilibrium potential is less than 1.5v. The cathode material can be made by using mechanical process or thermal method, and can be directly used as cathode material or used with other existing cathode material.

The invention provides a battery, comprising a cover plate, a shell, a battery cell and electrolyte. The battery cell and the electrolyte are sealed in the shell of the battery, and the cover plate is hermetically connected with the shell. The battery cell comprises a positive polar plate, a negative polar plate and a diaphragm arranged between the positive polar plate and the negative polar plate. A positive polar lug is arranged on the positive polar plate, and a negative polar lug is arranged on the negative polar plate. The battery cell is further internally provided with a positive polar current and heat conducting member and a negative polar current and heat conducting member, and the positive polar current and heat conducting member and the negative polar current and heat conducting member are mutually insulated. The positive polar current and heat conducting member and the positive polar lug are conducted; the negative polar current and heat conducting member and the negative polar lug are conducted; the positive polar current and heat conducting member and / or the negative polar current and heat conducting member penetrate(s) through the cover plate to leading out current. According to the invention, the internal heat of the battery cell can be reduced rapidly, substances on the polar plates can be prevented from further thermal reaction, and thus, the safety performance of the battery is increased. Meanwhile, the stability of the internal temperature of the battery cell is guaranteed, the cyclic performance and the like of the battery are improved. In addition, the temperature at all parts in the battery cell can be ensured to be consistent so as to eliminate temperature differences and make the reaction temperature of all parts of the polar plates consistent. Meanwhile, the current and heat conducting members can play roles of backbone and support to support the battery cell, and is beneficial to not only assembly but also winding of the battery cell.