34results about How to "Improve lithium intercalation capacity" patented technology

The invention discloses a multilayer positive plate with a lithium/sodium supplementing function, a battery and a preparation method, and belongs to the field of energy storage devices. The multilayerpositive plate comprises a current collector, a positive electrode material layer and a lithium/sodium supplement material layer. A positive electrode material layer and a lithium/sodium supplementing material layer are symmetrically arranged on the two sides of the current collector. The positive electrode material layer and the lithium/sodium supplementing material layer are laminated. The lithium/sodium supplementing material layer contains a special lithium/sodium-containing functional material. When the positive electrode is charged for the first time, a decomposition reaction occurs, sothat lithium/sodium ions in molecules of the positive electrode are irreversibly released into the battery, and the released lithium/sodium ions are supplemented into the negative electrode of the battery through an electrolyte, so that the problem of poor performance of the whole battery caused by low initial charge-discharge coulombic efficiency of an existing high-capacity negative electrode material is solved. The composite positive plate can efficiently supplement lithium/sodium to the negative electrode in the lithium/sodium ion total battery, has no adverse effect on the positive electrode material and the total battery, and can improve the energy density and the utilization rate of the positive electrode material of the battery, so that the cost of the battery can be reduced.

The embodiment of the invention provides a lithium ion battery negative electrode material. The lithium ion battery negative electrode material comprises a negative electrode active material, a conductive agent, a bonding agent and an organic solvent, wherein the negative electrode active material comprises lithium titanate Li4Ti5O12 and transition metal sulfide; the lithium titanate Li4Ti5O12 accounts for 50%-95% of the total mass of the negative electrode active material; the transition metal sulfide is one or more of NiS, FeS2, FeS, TiS2, MoS and Co9S8; the negative electrode active material, the conductive agent and the bonding agent account for 70%-90%, 5%-20% ad 5%-10% of the total mass of the negative electrode active material, the conductive agent and the bonding agent respectively; the organic solvent accounts for 30%-70% of the total mass of the lithium ion battery negative electrode material. The lithium ion battery negative electrode material is high in capacity and has good cycling stability and durability. The embodiment of the invention further provides a preparation method of the lithium ion battery negative electrode material, a negative electrode plate containing the lithium ion battery negative electrode material and a lithium ion battery.

The invention discloses an aerospace safe and high-power lithium ion storage battery, which comprises a positive electrode plate, a negative electrode plate, a separation membrane and electrolyte, wherein the positive and negative electrodes are separated by the separation membrane; the positive electrode plate comprises a positive electrode current collector and a positive electrode active coating layer coating the surface of the positive electrode current collector; the positive electrode active coating layer comprises positive electrode active substances; the positive electrode active substance is a mixed system formed by ingredients A and ingredients B; the ingredients A are at least one material from lithium cobalt oxides, nickel-cobalt lithium aluminate and nickel-cobalt lithium manganate; a conducting carbon layer coats the outer surfaces of materials of the ingredients A; the mass ratio of the conducting carbon layer to the ingredients A is (0.1 to 2):100; the thickness of the carbon layer is the nanometer level; the ingredients B are selected from at least one material from lithium manganate and lithium iron phosphate; and the mass percentage of the ingredients B accounting for the positive material active substances is 5 percent to 50 percent. Compared with the prior art, the aerospace safe and high-power lithium ion storage battery has the advantages that a mixed positive material system is used, so that the rate performance and the safety performance of an aerospace lithium ion battery can be greatly improved; and the application of the lithium ion battery to an aerospace power supply is expanded.

The embodiment of the invention relates to a carbon nanotube hard carbon composite negative electrode material with a core-shell structure and a preparation method and application. The size range of the carbon nanotube hard carbon composite negative electrode material is 1-50 mum, and the carbon nanotube hard carbon composite negative electrode material is composed of an inner core and a carbon coating layer coating the inner core; the inner core comprises a first phase and a second phase; the first phase is a hard carbon material prepared by taking one or a combination of several of glucose, cane sugar, polyvinylpyrrolidone, starch polyvinylidene fluoride, novolac epoxy resin or polyvinyl chloride as a carbonization precursor, the size range is 1-40 mum, and the Raman spectrum Id/Ig range is 0.7-0.9; the second phase is a carbon nanotube, and the size of the second phase is 1-50 nm; the carbon coating layer is prepared by a gas phase method, a liquid phase method or a solid phase method, and the Raman spectrum Id/Ig range is 0.7-1.3; in the carbon nanotube hard carbon composite negative electrode material, the mass fraction of the first phase to the second phase to the carbon coating layer is equal to (0, 100%) to (0, 60%) to (0, 40%).

The invention provides a composite cathode material for a lithium ion battery and a preparation method thereof. The composite cathode material of the invention comprises nano Si and graphitized needle coke; the average grain diameter is 5-15 microns; and the mass content of the nano Si in the composite cathode material is 5-30 percent. The composite cathode material of the invention not only improves the lithium embedding capacity of needle coke by 2.5-5 times but also overcomes the defects of low conductivity and easy volume expansion of silicon with high lithium embedding capacity. The preparation method of the invention comprises the following steps of: grinding the needle coke; carrying out graphitization treatment at argon atmosphere; mixing with nano silicon; depositing carbon on the particle surface of Si/needle coke; and then carrying out surface treatment on the composite cathode material. On one hand, the preparation method of the composite cathode material solves the problem of lower lithium embedding capacity of a single needle coke cathode material, on the other hand, the preparation method of the composite cathode material overcomes the defects existing in the nano Si used as the cathode material.

The invention relates to the technical field of secondary batteries, in particular to an electrochemical device and electronic equipment. The electrochemical device comprises a positive electrode, a negative electrode and an electrolyte, wherein the positive electrode comprises a positive current collector and a positive active material layer arranged on the positive current collector, and the positive active material layer comprises a positive active material; the negative electrode comprises a negative current collector and a negative active material layer arranged on the negative current collector, and the negative active material layer comprises a negative active material; and when the electrochemical device is in a fully charged state, the terminal potential of the negative active material is AV, the excess coefficient of the electrochemical device is B, and a ratio of B/A is in a range of 13.2 to 26.3. According to the electrochemical device and the electronic equipment provided by the invention, the rate capability of a battery can be improved without influencing the energy density of the battery.

An embodiment of the present invention provides a negative electrode material of a lithium-ion battery. The negative electrode material of a lithium-ion battery comprises a negative electrode active material, a conductive agent, a bonding agent, and an organic solvent. The negative electrode active material, the conductive agent and the bonding agent account for 70% to 90%, 5% to 20% and 5% to 10% of the total mass of the negative electrode active material, the conductive agent and the bonding agent respectively. The negative electrode active material comprises Li4Ti5O12 particles and transition metal particles. The Li4Ti5O12 particles account for 50% to 95% of the total mass of the negative electrode active material. The transition metal particles comprise one or more kinds of following particles: nickel oxide particles, ferric oxide particles, ferroferric oxide particles, titanium dioxide particles, and cobaltosic oxide particles. The present invention solves the problem that the Li4Ti5O12 negative electrode material is low in specific capacity and cannot meet requirements for preparing a high-energy high-density lithium-ion battery.

The invention relates to a new-type cathode material -- SiC used in a lithium ion secondary battery. The lithium ion secondary battery, which is manufactured from a material containing such active substance SiC and a lithium plate, is characterized in that the lithium ion secondary battery has a charging voltage platform of 0.6V and a discharging voltage platform of 0.4V respectively, and a theoretical specific capacity of up to 2680 mAh/g, and has a good charge-discharge cycle performance and environmentally-friendly and pollution-free characterizations. The SiC is a new-type, high capacity and high safety lithium ion battery cathode material with promising applications.

The invention discloses an alumina-modified graphene lithium ion battery anode material and a preparation method thereof, which belong to the technical field of lithium ion battery anode materials. The alumina-modified graphene lithium ion battery anode material consists of the following raw materials: nano-silicon powder, carbon fibers, graphene, carbon nanotubes, ethylene carbonate, alumina andpolyacrylic acid; and the lithium ion battery anode material is prepared by steps such as ultrasonic treatment, magnetic stirring, microwave treatment and high-temperature calcination. According to the invention, by means of a reinforcing system composed of ethylene carbonate, alumina and polyacrylic acid, the lithium intercalation capacity, lithium deintercalation capacity, initial coulombic efficiency and cycle performance of the alumina-modified graphene lithium ion battery anode material are increased.

The invention discloses a preparation method of a sodium-nitrogen in-situ doped ternary material, which comprises the following steps: uniformly mixing a lithium source, a sodium source and a ternaryprecursor Ni,1-a-b>CoMn (OH)<2> weighed according to a molar ratio, sintering at 700-900 DEG C in an oxygen-enriched atmosphere containing a nitrogen source, and naturally cooling to obtain the sodium-nitrogen in-situ doped ternary material Li<1-y>Na<y> (Ni<1-a-b>CoMn) N<x>O<2-X>, wherein x is larger than 0 and smaller than 0.1, y is larger than 0 and smaller than 0.1, 1-a-b is larger than 0.5 and smaller than 1, a is larger than 0 and smaller than or equal to 0.2, and b is larger than 0 and smaller than or equal to 0.2. The sodium-nitrogen in-situ doped ternary material prepared by theinvention not only is simple in preparation process, but also can effectively improve the capacity, the cycle performance and the rate capability of the ternary material.

The invention provides lithium ion battery silicon substrate composite negative electrode materials and a preparation method of the lithium ion battery silicon substrate composite negative electrode materials, and belongs to the technical field of lithium ion batteries. The prepared lithium ion battery silicon substrate composite negative electrode materials comprise, 23-56 wt% of silicon, 12.1-75.4 wt% of magnesium oxide and 2-12 wt% of graphene. A magnesiothermic reduction method is adopted, and magnesium powder serves as a reducing agent for reducing oxide of silicon (SiOx, and x is larger than 0.5 and smaller than 2) to prepare silicon/magnesium oxide composite materials. Then, the magnesium oxide attached on a reaction product on the surface of the silicon serves as a catalyst. A carbon source is adopted to carry out catalytic chemical vapor deposition so as to generate the graphene. The silicon/magnesium/graphene composite negative electrode materials are prepared. According to a prepared silicon substrate lithium ion battery, after magnesiothermic reduction is carried out on the oxide of the silicon, the magnesium oxide is generated on the interior of the oxide of the silicon, a volume effect of the silicon is relieved, the magnesium oxide generated on the interior and the exterior of the oxide of the silicon has the function of the catalyst, the graphene is catalyzed and generated, the volume effect of the silicon can be further relieved, and electrical conductivity of the materials is remarkably strengthened.

The invention discloses a titanium dioxide (B) negative electrode material with improved performance and a preparation method thereof. The titanium dioxide (B) negative electrode material is prepared from the following raw materials in parts by weight: 130-195 parts of titanium dioxide (B), 20-85 parts of tetraethoxysilane, 60-135 parts of graphite, 90-130 parts of a lithium source, 5-13 parts of a dopant, 25-35 parts of a carbon source and 35-45 parts of ionic liquid. The raw materials are prepared through the procedures of mixing, roasting, dispersing, grinding, drying, wrapping and sintering at a time. The negative electrode material prepared by the formula and the preparation method disclosed by the invention has excellent capacity performance, cycle performance, rate charge-discharge performance and first charge-discharge efficiency.

The invention discloses a preparation method of a hard carbon-based negative electrode material. The preparation method comprises the preparation steps of adding an alcohol solvent into bottom glycerol residues, stirring and heating to boil until the bottom glycerol residues are dissolved into liquid; adding dimethylamine into the glycerol residue solution; putting the aminated glycerol residue solution into a high-temperature heating furnace, and carrying out primary carbonization treatment; putting the glycerol residues subjected to primary carbonization into a plasma sintering furnace, vacuumizing, pressurizing, heating and sintering; putting the secondarily carbonized glycerol residues into an electric arc furnace, heating and sintering the secondarily carbonized glycerol residues under the protection of inert gas, and carrying out tertiary carbonization treatment; mixing the hard carbon-based material and a conductive agent, grinding, dispersing in absolute ethyl alcohol, adding an adhesive, uniformly stirring, drying and tabletting to obtain the hard carbon-based material negative electrode material. The bottom glycerol residues used in the method are rich in carbon resources, can be recycled, have very high social and environmental benefits, and has great significance for realizing green sustainable development.