32results about How to "Improve capacity stability" patented technology

The invention provides compound cathode slurry of graphene high-power lithium batteries, relates to the technical field of cathode slurry of lithium batteries and aims to solve the technical problems that cathode slurry used in the prior art causes reduced energy storage capacity and poor cycle performance and stability of the lithium batteries, as a result, the lithium batteries easily heat and are short in service life and low in utilization rate during usage. Thus, the invention provides the compound cathode slurry of graphene high-power lithium batteries. Compared with traditional cathode slurry for the lithium batteries, the prepared compound cathode slurry has the battery capacity reduced from 195.256 mAh/g to 193.658 mAh/g and the capacity retention rate up to 99.18% under the conditions that the temperature is 35 DGE C and 1C charge and 6C discharge are circulated 500 times, the discharge specific capacity and attenuation resistance are improved, and the high cycle life and high capacity stability are realized.

The invention relates to the technical field of battery materials, in particular to a sulfur/vanadium disulfide/MXene composite material as well as a preparation method and application thereof. According to the preparation method disclosed by the invention, the sulfur loading capacity can be improved due to the high specific surface area and a large number of active sites of the sulfur loading material MXene; MXene has unique flexibility and conductivity, so that the volume change of the positive electrode material can be buffered, and the conductivity of the composite material can be improved; the surface of the MXene is provided with a large number of functional groups and static electricity, so that vanadate ions can be attracted to generate a coordination effect; the vanadate ions areuniformly adsorbed on the surface of the MXene, so that the vanadate ions and a sulfur source generate uniform vanadium disulfide nanosheets on the surface of the MXene in situ at a proper temperature; by introducing the vanadium disulfide nanosheet with catalytic activity and high conductivity into MXene, lithium polysulfide can be chemically adsorbed, and the vanadium disulfide nanosheet can bequickly catalyzed and converted into insoluble Li2S2/Li2S in an electrolyte, so that a serious shuttle effect is inhibited, the stability of the lithium-sulfur battery is improved, and the cycle lifeof the lithium-sulfur battery is prolonged.

The invention relates to a composite anion-exchange membrane, its preparation and application. The membrane comprises a halomethylation polymer, an ion exchange-based precursor, a double-effect cross-linking agent and a reinforcing material. In the preparation process, the reinforcing material molecular chain is linked with the conductive ionic polymer molecular chain by the double-effect cross-linking agent to form a mandatory interpenetrating polymer network to avoid macroscopic phase separation. The preparation method disclosed herein is easy to operate and has the advantages of low cost and no damage to the membrane strength in the implementation process, the obtained anionic membrane has stable interface and mechanical stability, and the conductivity and swelling resistance of the membrane can be simultaneously guaranteed.

The invention relates to the technical field of nanometer materials, in particular to a sulfur/tin oxide/graphene battery cathode material, a preparation method and a lithium sulfur battery. The invention discloses a preparation method of a sulfur/tin oxide/graphene battery cathode material, comprising the following steps: Step 1, nitrogen doped graphene and a tin salt solution are hydrothermallyreacted to obtain a graphene-tin oxide nano-composite material; and Step 2: the graphene-tin oxide nano-composite material and elemental sulfur are mixed to obtain a mixture, and a vacuum melting diffusion reaction is carried out on the mixture to obtain a sulfur/tin oxide/graphene battery cathode material. The invention also discloses a sulfur/tin oxide/graphene battery cathode material preparedby the method and a lithium sulfur battery thereof. The invention solves the technical problems that the elemental sulfur in the prior art cannot be effectively utilized in the cathode material of thelithium sulfur battery, thereby leading to short service life, and poor conductivity, cycle stability and safety performance of the lithium sulfur battery.

The invention provides a modified aluminosilicate additive for lithium sulfur battery electrolyte and a preparation method thereof, Y-type molecular sieve precursor was prepared by sodium meta-aluminate, sodium hydroxide and sodium silicate, then mesoporous silicate aluminate was obtained by surfactant and acid-base crystallization, finally mesoporous silicate aluminate was modified by organic lithium salt to make organic lithium source enter mesoporous silicate aluminate pores, and mesoporous silicate aluminate particles loaded with lithium were obtained. The additive prepared by the invention has stable structure, Through the adsorption of modified mesoporous aluminosilicate on polysulfide in electrolyte, The polysulfide is immobilized in the solid particles, which effectively solves theproblem that the electrolyte of the existing lithium sulfide battery is difficult to control the dissolution of lithium polysulfide for a long time, inhibits the polysulfide from passing through theelectrolyte through the separator, thereby keeping the negative electrode material from being corroded, improving the capacity stability of the battery, and improving the long-cycle performance of thebattery.

The present disclosure is directed to a graphene-vanadium oxide nanowire including a nanowire core including vanadium oxide and a shell formed on the surface of the nanowire core and including graphene oxide. The graphene-vanadium oxide nanowire having improved capacity stability can be provided by using the graphene-vanadium oxide nanowire according to the present disclosure, the method for preparing the same, and a positive active material and a secondary battery including the same. In addition, by using the graphene-vanadium oxide nanowire according to the present disclosure as a positive active material, it is possible to provide a secondary battery having improved cycle characteristics and capacity retention rates.

The invention provides a lithium battery cell composite coated positive electrode material, a preparation method thereof, and a lithium ion battery. The improvement of material performance can be realized by introducing a lithium source, aluminum, magnesium or titanium element into a nickel cobalt lithium manganate positive electrode material. By using an assistant containing a silicon-based additive, excellent bonding performance between the material and a coating agent can be realized. Through coating by the method, the stable and reliable material can be obtained and is applied to the manufacturing process of the lithium ion battery. Not only are the electrical properties (including cycle performance) of the battery improved, but also the safety performance of the battery cell is improved, and the improvement effect on needling is particularly remarkable.

The invention relates to a preparation method for a lithium ion battery negative electrode material, and belongs to the technical field of a lithium ion battery. The preparation method comprises the steps of taking and placing silicate glass in a ball-milling tank, adding a sodium chloride solution for ball-milling, and sieving to obtain silicate glass powder; taking and placing Arabic gum and tragacanth gum in the ball-milling tank for ball-milling, and sieving to obtain tragacanth gum and Arabic gun mixture power; mixing the silicate glass ball-milling powder, the Arabic gum and the tragacanth gum, adding zinc powder, and performing stirring to obtain a colloid powder mixture; filling the colloid powder mixture in a die, performing pressing and pressure preservation, placing the die in abaking box, and performing standing and cooling to a room temperature after thermal curing to obtain a cured material; and placing the cured material in a tubular atmosphere furnace, introducing nitrogen to remove air, controlling a temperature, performing heat preservation and carbonization, and performing standing and cooling to the room temperature, thereby obtaining a silicon carbon compositenegative electrode material. The obtained negative electrode material has good rate performance, high capacity and good conductivity, and the application of the silicon negative electrode material isexpanded by electrical contact.

The invention relates to a graphene-based positive electrode material and a preparation method thereof and a lithium-sulfur battery. The preparation method of the graphene-based positive electrode material comprises the following steps: dispersing an MXene/graphene composite material, a copper salt and a sulfur source in a solvent to obtain a first mixed solution; putting the first mixed solutioninto a closed pressure system, and carrying out solvothermal reaction at 100-180 DEG C for 18-24 hours to prepare a copper sulfide/MXene/graphene nano composite material; mixing the copper sulfide/MXene/graphene nano composite material with elemental sulfur, performing grinding, and performing standing at 155-180 DEG C for 10-18 hours to prepare a graphene-based positive electrode material; and the MXene is Ti<3>C<2>. The positive electrode material prepared by adopting the method can improve the electrochemical performance of the lithium-sulfur battery.

The invention discloses a high-capacity low-voltage chip-type laminated aluminum capacitor and a preparation method thereof, and belongs to the technical field of capacitors, the high-capacity low-voltage chip-type laminated aluminum capacitor comprises a shell, a plurality of cathode waterproof shells are arranged in the shell, silver-containing cathode layers are arranged on the inner sides of the cathode waterproof shells, carbon-containing cathode layers are arranged on the inner sides of the silver-containing cathode layers, and the carbon-containing cathode layers are arranged on the inner sides of the carbon-containing cathode layers. An electrolyte layer is arranged on the inner side of the carbon-containing cathode layer, an aluminum foil body is arranged on the inner side of the electrolyte layer, a positive electrode gasket is fixedly installed in the shell and makes contact with the aluminum foil body, a positive electrode leading-out terminal is arranged on the surface of the positive electrode gasket, one end of the positive electrode leading-out terminal makes contact with the positive electrode gasket, and the other end of the positive electrode leading-out terminal makes contact with the aluminum foil body. And the other end of the positive electrode leading-out terminal extends to the outer side of the positive electrode leading-out terminal, and a negative electrode leading-out terminal is arranged in the shell. On the basis of realizing large capacitance of the capacitor, the capacitor can bear high temperature, and the liquid leakage probability is reduced.

The invention relates to a graphene-loaded multi-metal oxide-coated positive electrode material as well as a preparation method and application thereof. The preparation method comprises the steps that organic metal salt containing hydrogen bonds is added into an alkaline solution containing graphene, and graphene multi-metal hydroxide is obtained through a hydrothermal reaction or a solvothermal reaction or a mixed solvothermal reaction, wherein the organic metal salt specifically comprises at least two of a nickel source, a cobalt source, a manganese source, an aluminum source, an iron source and a magnesium source, the solvent of the hydrothermal reaction is water, a solvent of the solvothermal reaction comprises one or more of methanol, dimethylformamide, ethanol, acetonitrile, acetone, ethyl acetate, isopropanol, tetrahydrofuran, propanol, n-butyl alcohol, n-propanol and isopropanol, and a mixed solvent in the mixed solvothermal reaction comprises water and the solvent, and the volume ratio of the water to the solvent is 1:0.5 to 1:3; and the graphene multi-metal hydroxide and a positive electrode material are mixed for coating, and calcining is conducted to form the graphene-loaded multi-metal oxide-coated positive electrode material.

The invention discloses an aging and capacity grading method for a lithium ion battery. The method comprises the following steps: performing high-temperature aging on a to-be-aged battery for 18-24 hours after liquid injection and sealing; performing charging at 1C to 3.65 V, and performing aging at high temperature for 18-24 hours; performing discharging at constant current of 1C for 5-10 minutes; performing charging to 3.65 V at a constant current and a constant voltage of 1C and a cut-off current of 0.2 C; performing discharging to 1.85 V to 2V at a constant current of 1C; performing charging to 3.65 V at a constant current and a constant voltage of 1C and a cut-off current of 0.2 C; performing discharging at a constant current of 1C to 2V-2.5 V; discharging the gradient small current to 2V; and performing charging for 30 minutes at a constant current of 0.2 C. According to the method, the compactness of an SEI film of a battery cell is ensured by adopting a low-voltage aging mode and a high-voltage aging mode, and then the activity of a battery material is activated by adopting a shallow discharging, deep charging and deep discharging mode during capacity grading, so that the difference between the first capacity grading discharging capacity and the subsequent use capacity is small; meanwhile, the battery capacity stability is obviously superior to that of a battery prepared by an original capacity grading process in the aspect of long-term circulation.