21results about How to "Reduce concentration polarization" patented technology

The invention discloses a method for selectively separating valuable metals from a positive electrode material of a waste lithium battery, and belongs to the technical field of resource recycling of waste lithium ion batteries. The method comprises the following steps: preparing an aprotic deep eutectic solvent (DES) as a leaching agent and an electrolyte at the same time; the method comprises the following steps: adding a waste positive electrode material into DES, and leaching to obtain a DES leaching-electrolyte system; according to the method, the pulse voltage is applied in stages, selective separation of nickel, cobalt and manganese is achieved by controlling the pulse peak voltage (the first stage is-0.8 V to-1.0 V, the second stage is-1.0 V to-1.2 V, and the third stage is-1.2 V to-1.5 V), and the pulse frequency and the duty ratio are used for regulating and enhancing mass transfer and restraining side reactions. According to the method, the metal deposition potential difference is expanded through DES coordination regulation and control, efficient selective separation of nickel, cobalt and manganese is achieved in combination with pulse step-by-step voltage control, and the method has the advantages of being high in separation efficiency, few in side reaction, simplified in process, high in product purity and the like.

The utility model relates to the technical field of circuit board processing, in particular to a current adjusting device for circuit board electroplating, which comprises an electroplating box, a portal frame is mounted in the middle of the top of the electroplating box, an electric cylinder is mounted in the middle of the top of the portal frame, and the output end of the electric cylinder is fixedly mounted in the middle of the top of a transverse plate. A rotating shaft is rotatably mounted on the side, away from the anode, of the transverse plate, a clamping assembly is arranged at the bottom of the rotating shaft, a conductive slip ring connected with the cathode of the current regulator is mounted at the top of the rotating shaft, a stirring shaft is rotatably mounted on the other side of the transverse plate, and a plurality of stirring rods are mounted below the outer side wall of the stirring shaft. The electric cylinder drives the transverse plate to ascend, the U-shaped plate can be driven to ascend, the U-shaped plate drives a circuit board to ascend to leave electroplating liquid in the electroplating box, when a worker takes the circuit board, fingers do not need to stretch into the electroplating liquid, and harm to the fingers is reduced.

The utility model provides an electrode plate of a lithium ion battery. The electrode plate comprises a current collector and an active material layer, the active material layer comprises active material particles, porous nanofibers are distributed among the active material particles, the active material layer comprises n sub-layers, n is greater than or equal to 2 and less than or equal to 10, and the diameters of the porous nanofibers in the n sub-layers are sequentially reduced and / or the mass contents of the porous nanofibers in the n sub-layers are sequentially reduced from the surface layer of the pole piece to the current collector; and the thickness of the active material layer is 40-100 [mu] m. The electrode plate provided by the utility model has more excellent liquid absorption and liquid retention performance, increases electrolyte rapid diffusion channels, can greatly improve wettability of a thick electrode, improves ionic conductance of the electrode plate, reduces concentration polarization in the thickness direction of the electrode plate, and solves the problems of SOC difference in the thickness direction of the electrode plate and low capacitance, rate difference and circulation difference of the thick electrode.

This invention belongs to the field of metal refining processes and provides a parallel flow copper electrolytic refining process. The process involves setting up a balance tank outside the copper electrolytic cell, with crude copper anode plates and stainless steel cathode plates alternately arranged inside the cell and guided by flow guides. A cathode-wall flow channel is formed between the flow guides and the cell wall. Slit nozzles are set on the flow guides along the length of the cell, allowing the electrolyte to be sprayed from the cell side onto the cathode surface and form a parallel flow along the cathode wall. An anode collecting tank is set at the bottom of the copper electrolytic cell. A hydrodynamic barrier is constructed by adjusting the pressure difference between the cathode-wall flow channel and the anode collecting tank, inhibiting the migration of anode sludge to the cathode. The impurity-rich electrolyte from the anode collecting tank is introduced into an online impurity removal unit for treatment and then returned to the balance tank. After mixing with the electrolyte in the cathode circulation branch, it re-enters the cathode-wall flow channel, thereby obtaining cathode copper with uniform composition and controlled impurities.

This invention discloses an apparatus and method for rapidly separating small molecule compounds from traditional Chinese medicinal materials, relating to the field of extraction and separation technology of traditional Chinese medicinal materials. The apparatus for rapidly separating small molecule compounds from traditional Chinese medicinal materials includes: a material tank, a filter screen, a delivery pipe, and a membrane module. The material tank is used to contain the medicinal materials and solvent, and a discharge port is provided at the bottom of the material tank; the filter screen is positioned above the discharge port; one end of the delivery pipe is connected to the discharge port of the material tank, and a pump is installed on the delivery pipe; the inlet of the membrane module is connected to the other end of the delivery pipe, and the retentate outlet of the membrane module is connected to the material tank; when the pump is turned on, it can pump the medicinal solution in the material tank to the membrane module. This invention can reduce production costs and operational difficulty, and improve production efficiency.

This invention discloses a dynamically responsive electrolyte, its preparation method, and its applications. The electrolyte comprises a soluble metal salt, an active metal cation, an electric field-responsive ligand, and a self-healing additive. The molar ratio of the soluble metal salt, active metal cation, electric field-responsive ligand, and self-healing additive is 1:(0.05~6.0):(0.001~0.2):(3~100). The concentration of the soluble metal salt in the solvent is 0.2M to 5.0M. This electrolyte can intelligently and dynamically respond to changes in the local electrochemical environment, exhibiting the characteristics of actively intervening in and inhibiting dendrite growth.

The invention relates to the technical field of electrochemical energy storage materials and preparation, and discloses a forestry and agricultural residue-based carbon material and application thereof in a zinc ion battery, the forestry and agricultural residue-based carbon material is prepared by taking forestry and agricultural residues as raw materials through cellulose extraction, three-dimensional skeleton construction through aerogel, high-temperature carbonization, potassium hydroxide activation pore-forming and electrochemical surface modification. The obtained carbon material has a three-dimensional hierarchical connected network structure composed of micropores, mesopores and macropores, and the surface of the carbon material is rich in oxygen-containing zinc-loving sites for inducing uniform deposition of zinc. When being used as a zinc-free negative electrode carrier of a zinc ion battery, the hierarchical pore structure effectively reduces local current density and buffers deposition volume expansion, and surface zinc-loving sites obviously reduce nucleation overpotential. Through cooperative regulation and control of a physical structure and surface chemistry, zinc dendrite growth and hydrogen evolution side reaction are effectively inhibited, coulombic efficiency, long cycle stability and rate capability of the battery are greatly improved, the process is controllable, and the cost is low.

The invention relates to the technical field of lithium batteries, in particular to a lithium battery electrode, a preparation method thereof and a lithium ion battery. The electrode comprises a current collector and a composite coating on the current collector, wherein the coating is formed by combining an interface function layer on the outer side and a current collector function layer on the inner side through a middle area with continuous transition of components and structures. Wherein the interface function layer adopts an active substance with an average particle size D50 of 1-5 [mu] m and contains a conductive agent accounting for 4-8% of the dry weight; and the current collector functional layer adopts an active substance with an average particle size D50 of 8-15 [mu] m, and the mass ratio of the active substance is not less than 94%. The preparation method comprises the following steps: sequentially coating the first slurry and the second slurry by using a coating die head to form a composite wet film, and then drying and rolling. According to the invention, by constructing a continuous gradient structure, an interlayer clear interface is effectively eliminated, the ion diffusion and electron conduction capabilities of the electrode are synergistically improved, and the rate capability and the cycling stability are remarkably improved while the high energy density is maintained.

The application discloses a eutectic solvent system silver electrolytic polishing solution and application thereof; the polishing solution is prepared from raw materials and has the following mass fractions: a eutectic solvent base solution with a molar ratio of choline chloride to ethylene glycol being 1:1.5 to 1:2.5, 0.6 to 1.0 parts of 5,5-dimethylhydantoin, 0.9 to 2.0 parts of citric acid, 0.3 to 1.0 parts of urea and 0.1 to 0.5 parts of sodium dodecyl sulfate; the application utilizes the multiple hydrogen bond cross-linking network formed by citric acid and DMH in the base solution to realize solubilization of a macromolecular complexing agent and reduce the viscosity of the system; through a dynamic step voltage polishing process and a homologous decomplexing post-processing method, the problems of low mass transfer efficiency, anode film residue and surface reduction blackening in a non-aqueous system are solved; the application can improve the mirror gloss of a silver workpiece surface, reduce the roughness to below 0.05 mu m and has high silver loading and excellent environmental stability.

This invention belongs to the field of micro / nano structure material design and battery energy storage technology, and relates to a method for preparing a three-dimensional graphene-COF interlocking material: First, by controlling the amination and reduction of graphene oxide, amine functional groups are precisely constructed on its surface, serving as active sites for heterogeneous assembly; then, in solution blending, the enhanced multiple intermolecular forces between the amine groups and the COF precursor drive the COF units to undergo oriented adsorption and two-dimensional ordered pre-assembly on the graphene surface, forming a molecular-level anchor array; subsequently, through a solvothermal reaction, interfacial covalent condensation and π-plane-induced epitaxial growth are synergistically achieved, causing the COF layer to crystallize and form a strongly coupled heterojunction with the deeply reduced and structurally repaired graphene at the molecular level; finally, after freeze-drying and shaping, a dual continuous conductive network carrier with a stable heterointerface, three-dimensional interlocking channels, and an intrinsic built-in electric field is obtained.

The invention belongs to the technical field of sodium-ion batteries, and particularly relates to a solid particle volatilization pore-forming type sodium-electricity dry-method positive plate as well as a preparation method and application thereof. The positive plate is prepared by compounding positive electrode diaphragms prepared from a positive electrode material by a dry method on two sides of a current collector, the positive electrode material comprises a positive electrode active material, a conductive agent, a binder and a pore-forming agent, the pore-forming agent is solid particle hexachloroethane, and the D50 particle size of the solid particle hexachloroethane is less than or equal to 0.3 mu m. And the solid pore-forming agent is added into the positive electrode and forms tiny pores after high-temperature sublimation, so that the porosity of the pole piece is improved, the electrolyte retention capacity is increased, the concentration polarization is reduced, and the rate capability is improved under high surface density, thereby improving the energy density of the sodium ion battery.

This invention discloses a lithium-sulfur battery binder, its preparation method, and its application, belonging to the field of lithium-ion battery technology. The binder is prepared by grafting polyvinyl alcohol (PVA) with 3-(3,4-dihydroxyphenyl)-DL-alanine (DOPA) onto the PVA molecular chain, with a molar ratio of (0.9~1.2):(0.2~1). This invention, through directional molecular structure design of the binder, simultaneously achieves rapid lithium-ion conduction, improved electrochemical reaction kinetics, and optimized electrode mechanical structure stability, solving the industry problem of traditional lithium-sulfur battery binders' single-performance limitations and inability to meet multiple electrode requirements. The preparation method employs a controllable grafting reaction to functionalize the binder's polymer backbone, introducing sufficient polar functional groups and lithium-ion conduction active sites onto the molecular chain. This balances the stability of the polymer chain's cross-linking structure with electrode interface affinity, synergistically improving interfacial ion transport efficiency. The binder provided by this invention has broad application prospects in lithium-sulfur batteries.

The invention relates to a gel electrolyte material based on a zwitter-ion covalent organic framework and a preparation method of the gel electrolyte material. The invention discloses a preparation method of a gel electrolyte material based on a zwitter-ion covalent organic framework. The preparation method comprises the following steps: (1) preparing a nanoscale film substrate from a chain alkane polymer by adopting electrostatic spinning; (2) immersing the nanoscale film substrate into a reaction solution containing a COF precursor, and carrying out an in-situ polymerization reaction to obtain a composite film material; (3) dispersing the composite film material in acetonitrile, adding sultone monomers in the presence of argon at room temperature, and carrying out nucleophilic ring-opening reaction to obtain a functional film material; and (4) placing the functionalized film material in an organic electrolyte solution containing lithium salt, and obtaining the gel electrolyte material through physical swelling action. According to the zwitter-ion covalent organic framework-based gel electrolyte material and the preparation method thereof disclosed by the invention, the problems of low ion conduction efficiency, poor interface stability and the like of the existing electrolyte are solved.

The utility model provides a kind of filtering membrane structure of spherical graphite reverse osmosis device belongs to spherical graphite reverse osmosis device technical field, the filtering membrane structure of this spherical graphite reverse osmosis device includes: spherical shell, filter membrane component, support framework, water inlet pipeline, water outlet pipeline and sealing ring;The spherical shell is made of stainless steel material, the surface of spherical shell is equipped with water inlet and water outlet, water inlet is located in the upper hemispherical surface of spherical shell, and water outlet is located in the lower hemispherical surface of spherical shell;The filter membrane component is arranged inside spherical shell, and the filter membrane component includes graphite filter membrane and membrane fixed frame, the graphite filter membrane is spherical and concentrically arranged with the inner surface of spherical shell;It can solve the technical problems that the filtering membrane structure of spherical reverse osmosis device in the prior art has uneven stress on membrane material, insufficient support strength, unreasonable fluid distribution, low filtration efficiency and short membrane life.

The invention provides a ferronickel-based self-supporting oxygen evolution electrode and a preparation method thereof. The preparation method comprises the following steps: S1, adding ferric salt, nickel salt and an additive into a solvent to obtain a metal seed solution; s2, an electrode substrate is placed in the metal seed solution, the surface of the electrode substrate is heated at the initial pH at the heating rate of 0.7-2.5 DEG C / min to form an iron-rich phase, when the pH reaches 6.5-7.5, a nickel-based transition layer is formed on the surface of the iron-rich phase at the heating rate of 0.1-0.7 DEG C / min, and when the pH reaches 7.5-8, the nickel-based transition layer is formed on the surface of the iron-rich phase at the heating rate of 0.1-0.7 DEG C / min; and stopping heating and carrying out heat preservation reaction to form the ferro-nickel layered double hydroxide on the surface of the nickel-based transition layer. The controllable preparation of the high-performance self-supporting electrode is realized by accurately controlling the hydrothermal reaction process, the pores of the three-layer structure prepared on the surface of the electrode substrate are sequentially increased from inside to outside, the discharge of reactant bodies and products is promoted, compared with the prior art, the ion diffusion path is shortened by the three-layer graded pore channels, the concentration polarization is obviously reduced, and the performance of the electrode is improved. The catalytic activity and the service life are both considered.

The invention discloses a high-wettability gradient aperture composite diaphragm and a preparation process thereof. The diaphragm comprises a polyolefin base membrane layer and a synthetic fiber web layer prepared by a spunlace process, the overall thickness of the diaphragm is 8-12 [mu] m, the aperture of one side facing the positive electrode is 30-50 nm, and the aperture of one side facing the negative electrode is 50-100 nm; and the synthetic fiber web layer contains a tannic acid modifier. The tannic acid modified synthetic fiber web layer in the composite diaphragm can provide better wettability for the composite diaphragm, and polar functional groups on the surface of the tannic acid modified synthetic fiber web layer can homogenize lithium ion flow, guide uniform deposition of lithium and inhibit generation of lithium dendrites. The polyolefin layer mainly provides mechanical strength, and forms a gradient aperture structure with the spunlace modified polyethylene layer, so that the uniformity of current density is improved, the uniform deposition of lithium is effectively induced, and the growth of lithium dendrites is reduced.

This invention relates to a europium-cerium flow battery electrolyte and its preparation method, belonging to the field of flow battery technology. The negative electrode electrolyte comprises europium salt and additives, while the positive electrode electrolyte comprises cerium salt and additives. The additives include phosphate-containing chelating agents and supporting and auxiliary electrolytes. The chelating agents provided in this invention have large molecular weights, avoiding cross-contamination caused by active ions crossing the membrane. Furthermore, the additives at both ends are identical, resulting in essentially consistent viscosity of the electrolytes at both electrodes, which helps maintain the consistency and stability of conductivity, allowing for more uniform electrochemical reactions within the battery. As a novel type of flow battery, the europium-cerium flow battery has a higher voltage window, thereby improving the battery's energy density and power density. Moreover, the combination of europium and cerium ions with chelating agents further enhances the redox kinetics, showing broad application prospects in new energy vehicles.

The application discloses a water-based electrolyte and a zinc ion hybrid capacitor comprising the water-based electrolyte. The water-based electrolyte is a water-based electrolyte for a zinc ion hybrid capacitor, and comprises a zinc salt, an electrolyte additive and water. The electrolyte additive comprises a first additive and a second additive. The first additive is an organic antifreezing agent, and the second additive is a heterocyclic nonane. The volume fraction of the organic antifreezing agent in the water-based electrolyte is greater than 0.1% and less than 40%. The water-based electrolyte of the application uses the organic antifreezing agent and the heterocyclic nonane as additives, and the two cooperate with each other. The water-based electrolyte can not only prevent freezing and avoid ice formation, but also modify the zinc negative electrode interface, reduce the Zn 2+ reduction rate, alleviate concentration polarization, thereby facilitating inhibition of dendrite growth, and can also inhibit the side reaction of the zinc negative electrode, thereby improving the low-temperature cycle performance of the zinc ion hybrid capacitor.

The superfine silver powder production equipment comprises a refining box, a vibration device and a fixing frame, the fixing frame is arranged in the refining box, the two sides of the fixing frame are installed on the two side walls of the refining box through buffer devices, a supporting frame is installed on the fixing frame, and the vibration device is arranged on the supporting frame. A plurality of cathode plates and a plurality of anode plates are installed at the lower end of the supporting frame, the anode plates are sleeved with anode bags, the vibration device comprises transmission boxes, driving motors, transmission rods, transmission assemblies and connecting rod assemblies, the transmission boxes are installed at the two ends of the refining box, the transmission rods capable of rotating are installed on the transmission boxes, one transmission rod is provided with the driving motor, and the other transmission rod is provided with the connecting rod assemblies. The two transmission boxes are connected through the conveying belt, the lower end of each transmission rod is connected with the transmission assembly, the transmission assembly is connected with the connecting rod assembly, and the connecting rod assembly is connected with the fixing frame. Through vibration of the negative plate, silver powder on the surface of the negative plate can be vibrated off in time, small-particle silver powder is prevented from being agglomerated, the powder scraping procedure is omitted, and time and labor are saved.

The invention relates to the technical field of fuel cells, and provides a gas diffusion layer and a preparation method and application thereof. The gas diffusion layer comprises a substrate layer and a microporous layer attached to the surface of one side of the substrate layer, the substrate layer is provided with stacked carbon fibers, substrate layer pores are formed among the carbon fibers, the microporous layer comprises stacked conductive particles, at least part of the conductive particles permeate into the substrate layer, and the microporous layer comprises first pores and second pores; wherein the aperture of the first pores is R1, R1 is larger than or equal to 5 microns and smaller than or equal to 10 microns, the aperture of the second pores is R2, R2 is larger than or equal to 1 microns and smaller than 5 microns, and the pore area rate of the first pores is 25%-35%. According to the gas diffusion layer, through the synergistic effect of the multi-stage distribution pores of the pore size, the air permeability is effectively improved while the performance is improved, so that the gas diffusion layer has good drainage performance and air permeability.

The invention provides a negative electrode material and a battery, the negative electrode material comprises graphite, holes are formed in the surface and / or the interior of the graphite, the pore volume of the negative electrode material is V cm < 3 > / kg, the true density is D g / cm < 3 >, the specific surface area is S m < 2 > / g, the graphitization degree is G%, VS / D is larger than or equal to 0.7 and smaller than or equal to 3.95, and G is larger than or equal to 89 and smaller than or equal to 93. According to the negative electrode material and the battery provided by the invention, the rate capability and the cycle performance of the graphite negative electrode material under high-rate current can be improved.