100results about How to "Improve liquid absorption and retention capacity" patented technology

The invention provides a preparation method of composite graphite to overcome the problems that the composite graphite prepared by the method in the prior art is low in energy density, poor in high-rate charge and discharge properties and high in expansion rate in the charging and discharging processes. The preparation method comprises the following steps: (S1) providing ultrafine carbon powder, wherein the ultrafine carbon powder comprises green coke and/or mesophase carbon green microspheres; (S2) mixing the ultrafine carbon powder with a binder to obtain a mixture A, mixing the mixture A with a catalyst to obtain a mixture B, and then carrying out combined treatment on the mixture B to obtain a precursor; (S3) carrying out graphitizing treatment on the precursor to obtain a semi-finished product; and (S4) crushing, spheroidizing, wrapping and sieving the semi-finished product to obtain the composite graphite. Meanwhile, the invention further discloses the composite graphite prepared by the method and a lithium ion battery. The composite graphite provided by the invention is high in energy density, good in liquid absorption and retention properties, good in isotropic property, good in high-rate charge and discharge properties and low expansion rate in the charging and discharging processes.

The invention relates to a lithium ion battery composite separator, a preparation method thereof, and a lithium ion battery, and belongs to the technical field of lithium ion batteries. The lithium ion battery composite separator comprises a base film; one side of the base film is coated with a hot-melting polymer coating; the other side of the base film is coated with a heat-proof coating; the melting temperature of the hot-melting polymer coating is lower than the hot-melting temperature of the base film; the melting temperature of the heat-proof coating is higher than the hot-melting temperature of the base film; the hot-melting polymer coating comprises the following ingredients by weight: 50 to 98 parts of one or more hot-melt polymer materials, and 2 to 50 parts of one or more agglomerants; the heat-proof coating comprises the following ingredients by weight: 50 to 92 parts of one or more heat-proof polymer materials, and 3 to 20 parts of one or more agglomerants. The lithium ion battery composite separator is favorable in liquid sucking and retention properties, low in heat blocking hole temperature, and high in separator breaking temperature, thereby being capable of obviously improving the safety and the electrochemical property of the battery.

The invention discloses a fast charge ternary material positive pole piece and a lithium ion battery comprising the same. The fast charge ternary material positive pole piece is characterized in that the positive pole piece is of a laminate structure, wherein a base layer is a mesh aluminum foil current collector, a ternary material composite layer, a lithium supplementary layer and a carbon layer are arranged in turn from inside to outside. The composite positive pole piece provided by the invention utilizes a characteristic of high porosity of the mesh current collector to shorten the transmission distance of lithium ions during charging and discharging processes, lithium compounds in the lithium supplementary layer provide sufficient lithium ions for the charging and discharging processes of batteries, and the rate performance of the material is improved depending on characteristics of high electrical conductivity of graphene and large current carried by the graphene; and in the outermost layer, a carbon nanotube is deposited on the inside and the surface of the lithium supplementary layer by vapor deposition, the transmission rate of electrons is improved, direct contact between the material and electrolytic solution is avoided, and occurrence of side reaction of the material is reduced, so that the first efficiency, the rate performance and the cycle performance of the material are improved.

The invention discloses a preparation method of a lithium titanate/carbon nano tube composite cathode material and belongs to the technical field of battery materials. A carbon nano tube grows on the surface of lithium titanate by a chemical vapour deposition method, and has the characteristics of uniform dispersion, high binding force and the like compared with a carbon nano tube directly doped in lithium titanate, the growing carbon nano tube can form a network structure on the surface of lithium titanate, and an important effect is exerted on improving structural stability of the material under the condition of high-rate discharge of a battery. The contact probability of the lithium ion battery with lithium titanate is increased and the internal resistance and polarization are reduced by using high conductivity of the carbon nano tube and the network structure formed by the carbon nano tube, the liquid absorption and keeping ability of the cathode material can be improved due to larger specific surface area of the carbon nano tube, and the high-rate discharge ability and recyclability of the battery are improved.

The invention provides carbon nano tube and carbon black composite dispersing liquid which comprises 1.0-5.0% of carbon nano tube, 1.0-10% of carbon black, 0.5-1.5% of dispersing agent and 88-95% of solvent. The invention further provides a preparation method of the carbon nano tube and carbon black composite dispersing liquid. The method comprises the steps of performing carbon nano tube grinding dispersion on the composite dispersing liquid in an organic solvent or water containing the dispersing agent by a horizontal sand mill, performing composite dispersion on dispersed carbon nano tube dispersing liquid and the carbon black by a high-speed disperser, and preparing the dispersing liquid with solid content of 6.0-10.0%. The composite dispersing liquid is uniform and stable, and has good flowability, dispersity and glossiness; when the composite dispersing liquid serves as a conductive agent of a lithium ion battery anode, the addition amount is greatly reduced and the comprehensive performance of a battery cell is greatly improved; and the preparation method is simple and practical, facilitates long-term stability, and is suitable for large-scale production and application.

The present invention discloses a lithium ion battery composite separation membrane and a preparation method thereof, and belongs to the technical field of lithium ion batteries, wherein at least a surface of a polyolefin separation membrane is coated with a modified natural rubber polymer coating. According to the invention, the polyolefin separation membrane and the modified natural rubber are combined to form the composite separation membrane, such that mechanical properties of the natural rubber can be improved, and the original pore closing characteristic of the polyolefin separation membrane can be maintained and utilized so as to improve safety of the battery, enhance bonding force between the separation membrane and the positive electrode and bonding force between the separation membrane and the negative electrode, eliminate the interface effect, and improve cycle stability of the battery; and the inorganic nanoparticles are added to the modified natural rubber latex, such that the crystallinity of the polymer can be reduced to a certain extent, the mechanical strength of the separation membrane and the carrier concentration can be increased, the interface compatibility between the separation membrane and the lithium electrode can be effectively improved, and the interface is stable.

The invention discloses a preparation method of a high-performance graphite negative electrode material for a lithium ion battery. The method comprises the following steps of 1) collecting petroleum coke micropowder in a shaper and a grinder in normal graphite production, and mixing the petroleum coke micropowder, ground expanded graphite powder, raw mesocarbon microbeads and an adhesive in a mixer for 0.5-3 hours according to a mass ratio of 1 to (0.01-0.3) to (0.7-1.5) to (0.1-0.2) to form a solid-phase coated mixture, wherein the frequency of the mixer is 30-50HZ; and 2) graphitizing the solid-phase coated mixture obtained in the step 1) to obtain the high-performance graphite negative electrode material for the lithium ion battery. The method is simple and feasible; micropowder wastes in a dust collector are recycled, so that the cost is reduced; the method is easy for large-scale industrial production; and the obtained graphite negative electrode material has the characteristics of high energy density, good liquid absorption and retention performance, good cycle performance, good isotropic performance, good high-rate charge/discharge performance and low expansion rate in a charge/discharge process.

The invention belongs to the field of preparation processes of lithium batteries and particularly relates to a negative pole material for a lithium ion power and energy storage battery, as well as a preparation method and a battery thereof. Based on the insufficiencies in modification of the negative pole material in the prior art, a mixed solution of a binder and a catalyst is firstly configured, and graphite-like materials with different structures are uniformly mixed to form a graphite mixed body with different graphite structure types and close combination; then a porous coated carbon material is prepared by Friedel-Crafts cross-linking reaction, and coating, carbonization, crushing and other treatment are performed on the graphite mixed body, thus the negative pole material with high compaction density, strong liquid absorption capability, excellent rate performance and good cycling performance is finally prepared.

A preparation method of a high-nickel ternary material used for a lithium ion battery. The ternary material is Li(Ni<0.6>Co<0.2>Mn<0.2>)O<2>, of which gram volume is not less than 180 mAh/g and service life retention rate after 2000 circulations is not less than 80%. The preparation method includes following steps: (1) preparation of a precursor solution; and (2) mix-calcination. During the preparation process, because an organic solution can reduce particle aggregation, a complexing agent can control the appearance and the compatibility between a titanium dioxide enhancing material and electrolyte, the ternary material is high in the gram volume (not less than 180 mAh/g) and is good in the service life retention rate after 2000 circulations (not less than 80%). The ternary material is easy to control in appearance, is simple in process and is suitable for industrialized production.

The invention discloses a preparation method of an oily polymer coated diaphragm, and belongs to the technical field of preparation of lithium ion battery diaphragms. The method comprises the following steps: 1, preparation of oily mixed slurry: firstly, uniformly mixing and stirring an oily solvent and ceramic powder, then adding modified PMMA and performing uniform stirring, adding PVDF and a PVDF copolymer and performing uniformly stirring, and then carrying out ball milling for 0.5-1 hour to obtain the oily mixed slurry, adding a pore-forming agent into the uniformly mixed slurry for 2 hours, and performing uniform stirring to obtain final oily polymer slurry; 2, coating: coating one side or two sides of a base film with the oily mixed slurry prepared at the step 1 in a dip-coating, intaglio coating, spraying and spot-coating manner to form an oily coating, and carrying out drying in a drying oven at the temperature of 40-90 DEG C to obtain the polymer modified PMMA/PVDF and the copolymer ceramic coated diaphragm thereof. The method is simple in process, high in production efficiency and compatible with existing production equipment, and the large-scale production can be achieved.

The invention discloses a carbon nano-tube net/Ni(OH)<2>/PPY composite electrode, a preparation method and application, belonging to the technical field of super capacitors. The carbon nano-tube net/Ni(OH)<2>/PPY composite electrode is a core-shell structure; a core is composed of Ni(OH)<2> and a carbon nano-tube net doped therein; and a shell is uniform and compact PPY formed through an electrochemical deposition method. The composite electrode exerts a double-electrode-layer effect by utilizing the carbon nano-tube net having high specific surface area; with the help of the pseudocapacitance characteristic of the nano metallic oxide Ni(OH)<2>, the specific capacity is increased; simultaneously, depending on the high electric conductivity and the high specific energy density of the polymeric conductive polymer PPY, the discharge capability of the super capacitors under a high rate can be improved; the carbon nano-tube net with a connection point in a composite pole piece is doped in Ni(OH)<2>; therefore, the electric conductivity and the liquid sucking and keeping capability of the material are easily improved; and furthermore, the structural stability of the material can be improved through a net type structure.

The invention belongs to the field of lithium ion battery material preparation, and particularly relates to a preparation method of a high-voltage ternary composition material. The preparation methodcomprises the steps of adding a ternary material precursor, a lithium salt, a vanadium salt and a manganese salt into a three-dimensional mixing machine, and performing uniform stirring and sinteringto obtain a material A; and adding the material A into urea and a graphene ion liquid mixed solution thereof, performing heating and heat preservation after uniform stirring, and performing spray drying to prepare the ternary composition material. A surface of the Ni-Co-Mn ternary positive electrode material is coated with the vanadium salt and the manganese salt, the voltage platform is improved,meanwhile, the conductivity of the material is improved by conductivity of graphene, the coating quality is improved by a special effect in the urea, a layer of uniform coating film is formed, and the cycle property and the rate performance of the material under a high-voltage condition are improved.

The invention discloses a lithium ion battery, a diaphragm and a preparation method thereof. The diaphragm comprises a base material and a coating arranged on the surface of the base material in a coating manner, wherein the material of the coating comprises polyacrylate modified hollow ceramic nanotubes.

The invention belongs to the field of lithium ion battery material preparation, and particularly relates to a lithium-rich ternary composite material and a preparation method thereof. The preparation method comprises the steps of firstly preparing lithium powder externally coated with a polymer, then adding the lithium powder into a ternary material, uniformly mixing the lithium powder and the ternary material, soaking in a lithium metaaluminate solution, and drying to prepare the ternary composite material with a core-shell structure. The prepared material utilizes the lithium powder coated with the ternary material for providing sufficient lithium ions during a charge-discharge process, so that the first-time efficiency and the rate capability thereof are improved; meanwhile, the lithium-ion transmission rate under the high-rate condition is improved by depending on the lithium ions in the lithium metaaluminate solution on the outermost layer; meanwhile, an outer shell layer has better compatibility with an electrolyte solution, so that the cycle performance is improved.

The invention discloses a composite super capacitor diaphragm material with good isolation performance. The composite super capacitor diaphragm material is prepared from the following raw materials in parts by weight: 35-40 parts of polyvinyl alcohol fibers, 33-35 parts of polypropylene fibers, 10-13 parts of polyacrylonitrile powder, 30-32 parts of acetone, 72-75 parts of N,N-dimethyl formamide, 8-10 parts of water-soluble PVA fibers at 70 DEG C, 4-5 parts of cationic starch, 4-5 parts of glass wool, 2-3 parts of liquid paraffin, 1.5-2 parts of dimethylsiloxane, 9-11 parts of clay, 2-3 parts of palmitic acid and 3-4 parts of polyester adhesive powder. The ingredients of the glass wool, the clay and the like are also added to preparation of a product through a series of modified additives, so that the breathability is good; the mechanical strength of the product is improved; the high-temperature tolerance is improved; the super capacitor material can also keep a good isolating state at a high temperature; and the service lifetime of a super capacitor is prolonged.

The invention discloses a supercapacitor composite separator material of high mechanical strength. The supercapacitor composite separator material is prepared by the raw material of the following parts by weight: 35-40 parts of polyvinyl alcohol fiber, 33-35 parts of mekralon, 10-13 parts of polyacrylonitrile powder, 30-32 parts of acetone, 72-75 parts of N,N-dimethyl formamide, 8-10 parts of water soluble PVA fiber of 70 DEG C, a moderate amount of water, 13-15 parts of calcium carbonate, 5-7 parts of glass fiber, 7-9 parts of mica powder, 2-3 parts of oxidized polyethylene wax, 1-1.2 parts of sodium dodecyl benzene sulfonate, 2-3 parts of waterborne polyurethane emulsion, 3-4 parts of animal glue and 1-1.5 parts of polydimethylsiloxane. The processed calcium carbonate, the glass fiber and the mica powder are added in the preparation process of nonwoven fabric and evenly dispersed in slurry so that the mechanical strength of the prepared product can be further enhanced, the product is enabled to be anti-tensile and is not liable to fracture, and thus the supercapacitor composite separator material of high mechanical strength is the supercapacitor used composite separator material of excellent performance.

The invention belongs to the technical field of lithium ion batteries, and specifically relates to a silicon-based thin-film composite pole piece and a manufacturing method thereof, and a lithium ionbattery. The manufacturing method of the silicon-based thin-film composite pole piece comprises the following steps: (1) uniformly mixing organosilane lithium, a film-forming additive and an ionic liquid, to obtain an electrolyte; (2) using graphene oxide as a working electrode and silicon as a counter electrode, and saturated calomel as a reference electrode, depositing silicon dioxide on the surface of the working electrode by an electrochemical deposition method in the electrolyte obtained in the step (1), to obtain a silica/graphene oxide composite material; (3) under a reducing atmosphere, heating the silica/graphene oxide composite material to 600-800 DEG C and keeping warm for 1 to 6 h, and then cooling to obtain a silicon-monoxide/graphene composite material, that is, a silicon-based thin-film composite pole piece. A lithium ion battery in which the silicon-based thin-film composite pole piece obtained by the method is a negative electrode has advantages of high specific capacity, excellent cycle performance, and excellent rate capacity.