83results about How to "Improve the utilization rate of active substances" patented technology

The invention provides a grapheme-coated sulfur/porous carbon composite material and a preparation method thereof, and relates to a grapheme-coated sulfur/porous carbon composite material used as the positive electrode material of a lithium-sulfur secondary battery and a preparation method thereof. The grapheme-coated sulfur/porous carbon composite positive electrode material provided by the invention can be used for solving the technical problem that the existing grapheme-coated sulfur-containing composite material used as the positive electrode material of a lithium-sulfur battery is low in electrochemical properties. The external surface of each of the particles of the grapheme-coated sulfur/porous carbon composite material provided by the invention is evenly covered with a graphene sheet, and a graphene conductive network is formed between the particles; the obtained grapheme-coated sulfur/porous carbon composite material has a hierarchical core-shell structure. The preparation method of the grapheme-coated sulfur/porous carbon composite material is obtained by adding a sulfur/porous carbon composite material to graphene slurry which is stable for a long time and in which graphene sheets are highly dispersed in water for mixing and coating. The positive electrode material has high specific capacity, long cycle life and excellent high-rate performance. Besides, the grapheme-coated sulfur/porous carbon composite material can be used as the positive electrode material of a lithium secondary battery.

The invention provides a hydrothermal preparation method of a graphene-coated sulfur/porous carbon composite material and relates to a preparation method of the graphene-coated sulfur/porous carbon composite material for a positive electrode material of a lithium-sulfur storage battery. The hydrothermal preparation method is used for solving the technical problem that the electrochemical property of the positive electrode material of an existing lithium-sulfur battery, namely a graphene-coated sulfur-containing composite material, is low. The hydrothermal preparation method comprises the steps of mixing and scattering the sulfur/porous carbon composite material with graphene slurry or oxidized graphene slurry, carrying out hydrothermal synthesis to prepare a hydrogel column, and drying to obtain the graphene-coated sulfur/porous carbon composite material. According to the graphene-coated sulfur/porous carbon composite material prepared by utilizing the hydrothermal preparation method, the outer surfaces of the graphene sheet layers are coated with sulfur/porous carbon composite material particles, a graphene conduction network is generated among the particles, and the obtained graphene-coated sulfur/porous carbon composite material is in a hierarchical core-shell structure; the positive electrode material has the high specific capacity, the long cycle life and the good rate capability; the composite positive electrode material can be used as a positive electrode material in a lithium secondary battery.

The invention relates to a polyvinylpyrrolidone modified graphene coated sulfur/porous carbon composite anode material and a preparation method thereof, which relates to a sulfur/carbon composite material applied to a lithium-sulfur secondary battery anode material and a preparation method of the composite material, and solves the technical problem of the existing lithium-sulfur battery anode material graphene-coated sulfur-containing composite material that the electrochemical property is low. The polyvinylpyrrolidone modified graphene coated sulfur/porous carbon composite material is characterized in that the outer surface of a sulfur/porous carbon composite material particle is uniformly coated with a polyvinylpyrrolidone modified graphene slab layer, a graphene conductive network is formed between every two adjacent particles, and a grading core-shell structure is formed. The preparation method comprises the steps of adding the sulfur/porous carbon composite material into graphene slurry modified by the polyvinylpyrrolidone, and mixing the sulfur/porous carbon composite material with the graphene slurry, and coating the sulfur/porous carbon composite material with the graphene slurry modified by the polyvinylpyrrolidone. The anode material is high in specific capacity, long in cycle life and good in high-rate performance.

There is provided an electrode for a lithium secondary battery where particles, composed of an active material capable of occluding and releasing lithium, are arranged on a current collector, the active material particle being directly bonded to the surface of the current collector in a state where the bottom of the active material particle is imbedded in a concave portion formed on the surface of the current collector. A second particle layer may be provided on a first particle layer comprising the active material particles directly bonded to the surface of the current collector.

The invention particularly relates to a preparation method of a sulfur-carbon composite positive electrode material for a lithium-sulfur battery. Sodium polysulfide is taken as the raw material, and the nano-scale sulfur particles generated by use of a chemical reaction are promoted to be melted by virtue of high-speed ball milling and go into carbon pores of conductive carbon black, and finally, the sulfur-carbon composite positive electrode material is prepared. The high-performance sulfur-carbon composite material is prepared by use of an in-situ wet ball milling method. According to the preparation method, the operation is simple and easy, the energy consumption is low, the cost is low, an environment-friendly effect is achieved, and the industrial production is easy. The thorough dispersion and fixation of sulfur on a conductive substrate are realized; besides, a high-concentration lithium salt electrolyte is adopted to inhibit the solution of polysulfide, and therefore, the cyclic stability and the active substance utilization rate of the material are improved. As a result, the sulfur-carbon composite material prepared by use of the in-situ wet ball milling method is a positive electrode material which is high in specific capacity, long in cycle life and high in rate performance and can be applied to the field of lithium secondary batteries.

The invention provides an in-situ carbon coating preparation method for a secondary lithium ion battery cathode material lithium nickel phosphate. The method includes:(1) dissolving a lithium source compound, a divalent nickel source compound, phosphate and a carbon source in a benzyl alcohol water solution; (2) carrying out a hydrothermal reaction at 100DEG C-200DEG C for 4h-10h; (3) performing pumping filtering, conducting washing with distilled water and absolute ethanol; (4) conducting drying at 50DEG C-100 DEG C; (5) fully grinding the dried powder, firstly carrying out a pretreatment, and then performing calcinations at high temperature so as to obtain the final product. The invention makes use of the in-situ carbon coating method to prepare near-spherical nanoscale LiNiPO4 particles, the specific surface area of active particles is increased, the electrochemical contact between active substances and a conductive agent is strengthened, the conductivity of the LiNiPO4 material is enhanced, and the charge and discharge performance of secondary lithium ion batteries is improved. Therefore, the lithium nickel phosphate can be taken as a potential secondary lithium ion battery cathode material.

Main chemistry constitutes of the Additive is ZnO and Co2O3. Conducting oxides such as Bi2O3íóCo2O3, Nb2O5, Y2O3, La2O3 can be added to the additive. Using mode of mixing and grinding solids, the method dopes Bi, Co, Nb elements; and using method of sol, the method leads in adulterants of Y and La elements and tetrabutyl titanate. Advantages are: (1) the zinc oxide based conducting oxide can be as center of crystallization; increasing use ratio of active material and discharge capacity, and reducing and preventing generation of tree like crystal of zinc, and raising cycle life of electrode; (2) reducing internal resistance of electrode as well as preventing zinc from solved in electrolyte, and hydrogen from separating out.

The invention discloses a membrane material for a lithium sulfur battery positive electrode, and belongs to the technical field of electrochemical batteries. The membrane material for making the lithium sulfur battery is designed against the disadvantages of poor conductivity, low active substance utilization rate and the like of traditional lithium sulfur batteries, and has the advantages of multilayer filter screen structure, prosperous gap, high conductivity, simple preparation technology and harmlessness to the environment. The membrane material for the positive electrode is placed between a positive plate and a diaphragm, so the dissolution of the polysulfide in the electrolyte in the charge and discharge process of the battery is effectively inhibited, and the corrosion of the polysulfide to a metallic lithium negative electrode is reduced. The lithium sulfur battery adopting the membrane material has a high active substance utilization rate and stable cycle performances, has an initial discharge specific capacity under a current density of 0.162mA/cm<2>, and still has a discharge specific capacity of above 702mAh/g after 50 times cycle; and compared with traditional lithium sulfur batteries, the lithium sulfur battery adopting the membrane material has the advantages of excellent performances and low cost, and lays a good foundation for the marketization of the lithium sulfur battery.

The present invention provides a preparation method for aluminum-coated nickel-cobalt lithium manganite and a lithium battery, and relates to the technical field of material preparation methods. The method comprises the steps of wet mixing, wet ball milling, spray drying, first sintering, dry ball milling and second sintering. Aluminum oxide coats a surface of nickel-cobalt lithium manganite obtained by the first sintering through the dry ball milling. Because the dry ball milling is adopted, lithium ions are not prone to form lithium dendrites on the surface of a negative electrode. After thesecond sintering, gram volume is not greatly reduced, and material properties are enhanced to a certain degree. The preparation method for the aluminum-coated nickel-cobalt lithium manganite not onlycan enhance cyclic properties of ternary materials and improve the utilization rate of active substances, but also can obviously improve the gram volume of the materials after the second sintering. The lithium battery provided by the present invention is prepared by the above preparation method for the aluminum-coated nickel-cobalt lithium manganite, and has good electrochemical property and longservice life.

The invention discloses a large-capacity double-bag type iron-nickel battery. A battery pole plate is composed of a bag type nickel positive pole plate, a bag type iron negative pole plate and a multilayered composite diaphragm or isolation grid located between the bag type nickel positive pole plate and the bag type iron negative pole plate; an electrode material of the bag type nickel positive pole plate is composed of a positive pole active material, a conducting agent, an additive and a binding agent; an electrode material of the bag type iron negative pole plate is composed of iron-basedoxide powder, a conducting agent, an additive and a binding agent; electrolyte is an alkaline solution which is at a barren liquor state and contains the additive. According to the large-capacity double-bag type iron-nickel battery disclosed by the invention, a formula of positive and negative poles is optimized, a formula of the electrolyte is optimized and a battery structure is adjusted, so that the charging and discharging performance, and circulating performance of the novel iron-nickel battery are improved; furthermore, the battery also has the advantages of high charging and dischargingvoltage platform, good over-charging and over-discharging resisting performance, low cost and the like.

The invention provides a preparation method of a conductive carbon material with a hierarchical porous structure. The method comprises: dissolving phenolic resin into an ethanol solution; dissolving a surface active agent F127 into an HCl-containing ethanol solution; then adding ethyl orthosilicate, silicon dioxide colloidal particles and the phenolic resin ethanol solution; transferring a mixture into a container, volatilizing ethanol, performing thermal polymerization in a reaction furnace of 100 DEG C to obtain a faint-yellow transparent thin film, and grinding the thin film into powder; putting the powder into a tubular muffle furnace, and performing carbonization under the nitrogen atmosphere protection; soaking a hierarchical porous structure carbon/silicon oxide composite material into HF of which the content is 5wt%, removing silicon oxide, only retaining carbon components of the hierarchical porous structure, washing a sample by using deionized water, and then performing drying to obtain the conductive carbon material with the hierarchical porous structure. According to the preparation method of the conductive carbon material with the hierarchical porous structure, the internal resistance of a lead acid battery electrode can be effectively reduced, and the utilization rate of active substances and the charge-discharge rate are improved; meanwhile, the electrode structure can be stabilized, and the recycling life is prolonged.

The invention discloses a method of preparing aluminum-substituted alfa-nickel hydroxide coated with beta-nickel hydroxide. The method comprises the steps of: dissolving nickel salt and aluminum salt in a 5:1 molar ratio of nickel to aluminum by using distilled water to prepare a mixture liquid; dissolving potassium hydroxide or sodium hydroxide in the distilled water to prepare alkaline solution of sodium hydroxide or potassium hydroxide; dropwise adding the alkaline solution into the mixture liquid, controlling a pH value, reacting, perform extraction filtration, washing, and drying to obtain aluminum-substituted alfa-nickel hydroxide powder; mixing aluminum-substituted alfa-nickel hydroxide with nickel ions, perform ultrasonic dispersion, dropwise adding the alkaline solution into the nickel salt solution which contains the aluminum-substituted alfa-nickel hydroxide, controlling the pH value, reacting, perform extraction filtration, washing, and drying to obtain the aluminum-substituted alfa-nickel hydroxide coated with the beta-nickel hydroxide. The method is simple in process and easy to control, the cost of raw materials is low, and the utilization rate and cycle performance of the aluminum-substituted alfa-nickel hydroxide coated with the beta-nickel hydroxide serving as an anode material active substance of a nickel-metal hydride battery are excellent.

The invention belongs to the field of battery manufacturing, and particularly relates to a slurry coating process-based method for preparing a thin thermal battery positive electrode and electrolyte combination electrode piece. The method comprises the steps: preparing homogeneous thermal battery positive electrode slurry, then coating a conducting substrate with the homogeneous thermal battery positive electrode slurry, drying, solidifying and pressing to obtain a thin thermal battery positive electrode piece; and preparing homogeneous thermal battery fused salt electrolyte slurry, coating the thin thermal battery positive electrode piece with the homogeneous thermal battery fused salt electrolyte slurry in a lamination manner, drying, solidifying and pressing so as to obtain the thin thermal battery positive electrode and electrolyte combination electrode piece. The thin thermal battery positive electrode and electrolyte combination electrode piece prepared by adopting the method has the advantages that the thickness can be reduced by 1/3-1/2 and is adjustable in the range of tens of micrometers to hundreds of micrometers, and the combination electrode piece has very high values on creating a new way in miniaturizing and thinning thermal batteries and promoting development of national defense industries.

The invention provides a manufacturing method of a current collector of a lead-acid storage battery. The manufacturing method comprises the following steps: preprocessing a lead or leaded alloy into particles and uniformly mixing the particles and low-density blended material particles as well as reinforced fibers; heating the uniformly mixed lead or leaded alloy, low-density blended material particles and reinforced fibers to a temperature interval of higher than a melting point of the lead or leaded alloy and lower than melting points of the low-density blended material particles and the reinforced fibers, extruding the mixture into a die to carry out forming processing to form the current collector of the lead-acid storage battery. The current collector manufactured by the technical scheme adopted by the invention has the lowest density of 3g/cm<3>; the largest weight of the current collector can be reduced by 70 percent to the greatest extent; compared with the surface area of a current collector manufactured by a conventional process, the surface area can be increased by 40 percent to the greatest extent; the intensity of the current collector is improved by 200 percent; the current collector manufactured by the manufacturing method can be widely applied to the lead-acid storage battery and is particularly applied to a high-energy-density, high-power and quick-charge start-stop battery.

The invention belongs to the technical field of lithium-sulfur batteries, and particularly relates to a preparation method of a layered double hydroxide composite material for a positive electrode of a lithium-sulfur battery. The preparation method of the layered double hydroxide composite material for the positive electrode of the lithium-sulfur battery comprises the following steps: (1) synthesizing AC-FeCoNi; and (2) synthesizing Cu SAs/AC-FeCoNi. Copper atoms are introduced into AC-FeCoNi through an in-situ cation exchange reaction to prepare the Cu SAs/AC-FeCoNi composite material, and the preparation method is simple, effective and easy to operate; and the prepared composite material has high conductivity and high specific surface area, and has a stable three-dimensional structure.

The invention provides a porous metal aeration electrode capable of producing hydrogen peroxide based on electrocatalysis, and a preparation method thereof, wherein the porous metal aeration electrodecomprises a porous metal matrix and an electrocatalytical active layer supported on the porous metal matrix, the porous metal matrix is a porous metal material formed by carrying out pressing sintering on a metal powder material, and the electrocatalytical active layer is a carbon material having a micro/nano structure. According to the present invention, the porous metal aeration electrode has characteristics of high hydrogen peroxide yield, high utilization rate of active material, good mass transfer effect, low energy consumption and long service life; and the preparation method is simple,cannot produce secondary pollution, and can reload and quickly repair the failed aeration electrode.

This invention discloses a colloid electrolyte containing rare earth used in the battery and its preparation method relating to a lead acid battery electrolyte and its method which includes sulfuric acid 34%-37%, sodium silicate 2%-3.5% counted in terms of SiO2, cerous ammonium nitrate 0.05-0.1%, Fe<0.004%. It's difficult for the said electrolyte to become the lean solution since its surface is 10%-15% higher than that of ordinary absorption sulfuric acid electrolyte, the actual capacity is increased, the constant current discharge time is prolonged, its density is high and temperature variance of charge/discharge is small, not easy to form 'heat out-off-control' harm the pole plates.

The invention discloses a triphenylthiol additive-containing lithium-sulfur battery electrolyte and a lithium-sulfur battery. The electrolyte comprises an ether solvent, a lithium salt and an additive, and the additive is 1, 3, 5-benzene trithiol. According to the electrolyte of the lithium-sulfur battery, small organic molecule mercaptan 1, 3, 5-triphenylthiol is used as an additive, and triphenylthiol can quickly generate a uniform organic-inorganic SEI layer with a lithium negative electrode in the lithium-sulfur battery, so that the generation of dendritic crystals of the lithium negative electrode is further improved; and meanwhile, a self-binding oligomerization reaction with a sulfur positive electrode in the lithium-sulfur battery can be carried out to generate phenyl polysulfide, so that the generation of polysulfide is reduced, and the dissolution loss of active substances is reduced. The benzene trithiol forms double-layer protection on the positive electrode and the negative electrode of the lithium-sulfur battery, so that the long cycle stability, coulombic efficiency and rate capability of the lithium-sulfur battery are effectively improved, and the lithium-sulfur battery has commercial application potential.

The invention discloses a lead-acid storage battery. The storage battery comprises a positive electrode, a negative electrode, a battery shell and a current converging body, wherein the positive electrode and the negative electrode have columnar strip physical shapes; a positive electrode columnar strip and a negative electrode columnar strip are parallel to each other and are arranged in an adjacent or nesting manner; the positive electrode columnar strip and the negative electrode columnar strip are isolated mutually by an isolation plate; each of the positive electrode columnar strip and the negative electrode columnar strip comprises an active material and a current collector; at least one part of each current collector is arranged in the interior or on the surface of the corresponding active material; and one end of each current collector is conductively contacted or combined with the corresponding active material while the other end is conductively connected with at least one kind of the current converging body, a connecting body between batteries or a battery output end point. The invention also discloses a lead-acid storage battery pack formed by the lead-acid storage battery. By means of improving the shapes and the array arrangement structures of the positive electrode and the negative electrode of the lead-acid storage battery, the performance of specific energy, deep discharging, high-current discharging capability, cycling life and the like of the lead-acid storage battery can be greatly improved.