109 results about "Charge transfer resistance" patented technology

The invention relates to the technical field of aircraft part processing, testing or inspection and the like, and provides an aircraft aluminum alloy plate aging evaluation method based on an equivalent circuit model, and the method comprises the following steps: collecting electrochemical impedance spectrums of samples with different exposure age limits, and extracting electrochemical impedance spectrum characteristics of the samples; establishing an equivalent circuit model comprising solution resistance, coating resistance, coating capacitance, Warburg impedance, anodic oxide film charge transfer resistance, interface capacitance, aluminum alloy matrix charge transfer resistance, interface electric double-layer capacitance, inductance and corresponding resistance of the inductance based on the characteristics, wherein the equivalent circuit model comprises the solution resistance, the coating resistance, the coating capacitance, the Warburg impedance, the anodic oxide film charge transfer resistance, the interface capacitance, the aluminum alloy matrix charge transfer resistance and the interface electric double-layer capacitance; and analyzing a resistance curve and a capacitance curve obtained by fitting the model to complete the evaluation of the corrosion and aging degree. According to the method, systematicness and accuracy of aging evaluation are improved, an electrochemical mechanism in the corrosion process can be disclosed, time correlation modeling of the aging process can be achieved, and the method is suitable for long-term service performance monitoring and service life prediction of the aviation aluminum alloy structure.

The invention discloses a lithium battery solid electrolyte interface film forming quality evaluation method. The method comprises the following steps: in a lithium battery formation stage or a circulation process, applying an alternating current disturbance signal with an amplitude of 1-20mV, and collecting full-band electrochemical impedance spectroscopy data in real time; a relaxation time distribution method is adopted to decouple the electrochemical impedance spectrum of the intermediate frequency region; constructing an equivalent circuit model containing SEI film characteristics, and fitting the decoupled electrochemical impedance spectrum curve by the equivalent circuit model; the compactness index of the SEI film is calculated according to the SEI film resistance and the film capacitance, and whether the compactness of the SEI film reaches the standard or not is judged according to the compactness index; and calculating a lithium ion diffusion coefficient by combining the charge transfer resistance and the Warburg diffusion impedance, and evaluating the SEI membrane ion transmission efficiency. According to the invention, non-destructive monitoring is supported, quantitative evaluation of SEI membrane compactness, ionic conductivity and short circuit faults in the module can be realized, and the cycle life and safety of the lithium battery are improved.

The invention discloses a low-temperature exposed lithium battery aging damage diagnosis method based on electrochemical nondestructive characterization, which comprises the following steps: firstly, acquiring electrochemical response data of a to-be-tested battery through electrochemical impedance spectroscopy (EIS) test and incremental capacity analysis (ICA); secondly, key characteristic parameters capable of representing ohmic internal resistance, charge transfer resistance and electric double-layer capacitance of the battery and phase change peak position, peak area, half-peak width and the like are extracted; and then, training a joint prediction model based on machine learning by using the extracted multi-dimensional features to judge whether the to-be-detected battery is subjected to over-low-temperature exposure or not and judge the current aging damage degree of the to-be-detected battery. According to the method, unique aging paths introduced by normal aging and low-temperature exposure can be effectively distinguished through a nondestructive testing means, accurate'traceability 'of historical damage of the battery and quantitative evaluation of the current state are achieved, and reliable technical support is provided for intelligent decision making of a battery management system (BMS), battery safety early warning and echelon utilization.

The invention relates to a microbial electrode online monitoring system and method based on multi-modal fusion and a self-repairing mechanism, and belongs to the technical field of environmental monitoring and bioelectrochemistry. Aiming at the problems of high cost, weak anti-interference capability, poor long-term stability, difficulty in precise decoupling of multi-parameter coupling and the like in the existing microbial electrode monitoring technology, the method comprises the following steps: synchronously acquiring multi-modal signals of a dual-wavelength differential near infrared spectrum and an electrochemical impedance spectrum; a front decoupling mechanism based on equivalent circuit fitting and reinforcement learning is combined to clearly distinguish change sources of charge transfer resistance and diffusion resistance; performing deep fusion on the decoupled features by using a convolutional neural network, and outputting a microbial activity score and a metabolite concentration; and a self-repairing electrode material and a closed-loop feedback control mechanism are introduced, and repairing is automatically triggered when electrode performance degradation is monitored. According to the invention, low-cost, high-precision and strong-anti-interference long-term stable in-situ monitoring of the microbial electrode is realized.

The invention provides a cobalt tungstate and bismuth vanadate photocatalytic material as well as a preparation method and application thereof, and belongs to the technical field of material synthesis and photocatalytic application. In the presence of monoclinic-phase decahedron BiVO4, CoWO4 nanoparticles grow in situ on an electron-rich (010) crystal face of the CoWO4 nanoparticles through a hydrothermal reaction, and the cobalt tungstate and bismuth vanadate photocatalytic material is obtained. According to the cobalt tungstate and bismuth vanadate photocatalytic material, a simple hydrothermal method is adopted, in the synthesis process, a CoWO4 precursor is guided by electrostatic interaction, preferentially adsorbed and subjected to nucleation growth on the (010) crystal face of BiVO4, a compact chemical bonding interface is constructed through selective growth, the charge migration distance is effectively shortened, and the photocatalytic performance of the material is improved. The interface charge transfer resistance is reduced to the greatest extent, and the formed binary photocatalyst has excellent effects on photocatalytic hydrogen evolution and tetracycline degradation.

The invention relates to an IrO2-Ta2O5 titanium anode coating based on graphene doping and temperature programming sintering synergistic enhancement and a preparation method of the IrO2-Ta2O5 titanium anode coating, and belongs to the technical field of electrode material preparation. According to the method, graphene is doped in an IrO2-Ta2O5 coating, the content of the graphene is controlled to be 0.2-0.8 mg / mL, preferably 0.6 mg / mL, the content of iridium is 26 g / m, and a 200-500 DEG C temperature programming sintering process is adopted. By optimizing the graphene dispersing and sintering process, the conductivity, the electrocatalytic activity and the structural stability of the coating are remarkably improved. Experimental results show that the coating has lower charge transfer resistance and higher electric double layer capacitance and oxygen evolution reaction activity, and the strengthening life of the coating exceeds 1100 hours and is far longer than that of a traditional titanium anode coating. The method is suitable for high-requirement electrochemical scenes such as electrolytic copper foil and chlor-alkali industry, and has a good industrial popularization prospect.

The invention belongs to the field of aluminum alloy processing, and provides a method for evaluating the corrosion resistance of an anodic oxide film and the corrosion capacity of a semi-synthetic cutting fluid, which comprises the following steps of: respectively taking a corrosive liquid or the semi-synthetic cutting fluid as an electrolyte and simulating a corrosive environment, and then taking an aluminum alloy sample as a working electrode to evaluate the corrosion resistance of the anodic oxide film and the corrosion capacity of the semi-synthetic cutting fluid; performing an electrochemical test in a corrosion environment to obtain charge transfer resistance Rct and corrosion current density Icorr, and then calculating a corrosion resistance index CI; the higher the obtained corrosion resistance index CI value is, the higher the corrosion resistance of the anodic oxide film of the aluminum alloy sample is, or the lower the corrosion capacity of the semi-synthetic cutting fluid is. And the corrosion resistance of the anodic oxide film or the corrosivity of the semi-synthetic cutting fluid can be rapidly and accurately evaluated.

The invention discloses a method for evaluating and strengthening interface characteristics of a copper-based composite material, and relates to the technical field of copper-based composite materials. A soil solution and carbon quantum dots are prepared, and the carbon quantum dots are added into the soil solution; the method comprises the following steps: simulating a corrosion process of copper-based composite materials with different aluminum contents in soil solutions with different carbon quantum dot contents, and carrying out polarization curve and electrochemical impedance spectroscopy analysis on the corroded copper-based composite materials by adopting an electrochemical workstation to obtain charge transfer resistance and impedance modulus values of the copper alloy composite materials; meanwhile, SEM, EDS and three-dimensional surface contour analysis are combined, and the surface morphology and roughness of the copper-based composite material are obtained; according to the method, the electrochemical method and the corrosion surface characterization method are combined, the change of the surface and interface characteristics of the copper-based composite material corresponding to different matching materials can be rapidly evaluated, so that the purpose of protecting the alloy material is achieved, and aluminum and carbon quantum dots are found to be capable of synergistically promoting the protection of the copper-based composite material.

The invention provides a nitrogen-vacancy carbon nitride / indium oxide heterojunction photocatalyst as well as a preparation method and application thereof, and belongs to the technical field of photocatalysts. The nitrogen vacancy carbon nitride is used as a framework of the catalyst, and the charge distribution of the carbon nitride can be adjusted by nitrogen vacancy defects, so that the carrier migration rate and the surface active site abundance are improved; the nitrogen vacancy also changes the charge recombination mode of the carbon nitride, the energy band structure of the carbon nitride is beneficially adjusted, the photovoltaic performance of the carbon nitride is improved, the visible light response range of the carbon nitride is widened, and the photocatalytic performance of the carbon nitride is remarkably improved; indium oxide is introduced to form a heterojunction with nitrogen vacancy carbon nitride, so that electron-hole recombination can be inhibited, a new electron transmission channel is generated, and the carrier transmission rate is increased; the band gap characteristic of indium oxide is consistent with the band gap characteristic of nitrogen vacancy carbon nitride, so that the photocurrent response intensity of the catalyst can be improved, the charge transfer resistance is reduced, and the photocatalytic performance is synergistically enhanced.

This invention relates to the field of water electrolysis and hydrogen energy utilization technology, and provides an in-situ electrodeposition method for improving NiMoP. x O y A method for studying the catalytic activity and stability of a self-supporting nickel-based hydrogen evolution electrode (NMOP). First, NiMoP... x O y The / NF self-supporting foam nickel-based electrode is prepared by immersing it in a nickel salt solution for a certain period of time, drying it, and then immersing it in a sodium sulfate solution for electrodeposition reduction reaction. This invention provides a simple and convenient method for adjusting the amount of metallic nickel deposited, ensuring its distribution among the active component particles of the electrode. This effectively improves the adhesion of the active component and prevents its detachment, significantly enhancing the hydrogen evolution activity and stability of the hydrogen evolution electrode. At an industrial current density of 100 mA / cm², the overpotential of the modified electrode prepared by this method is reduced by approximately 20% compared to the unmodified electrode, and the charge transfer resistance is reduced by approximately 41%. After 30,000 CV cycle accelerated durability tests, the increases in overpotential and charge transfer resistance are less than 7% and 26% of those of the unmodified electrode, respectively. Therefore, this invention has promising prospects for industrial application.

The application discloses a precision hardware fatigue damage detection method and system, and relates to the field of precision mechanical detection.The method comprises the following steps: coupling a flexible impedance sensing array with a precision hardware to be detected; the array substrate is made of polydimethylsiloxane, and the surface array groove is filled with a conductive hydrophilic composite gel formed by in-situ polymerization of acrylamide monomer, sodium alginate and nanometer carbon fibers, thereby forming a plurality of miniaturized impedance units; a constant pressure is applied through a pressure feedback control system, so that the gel produces elastic deformation to cover and compensate the micron-level roughness of the surface of the detection area; a micro-amplitude sinusoidal voltage excitation is applied, current response data in the swept frequency band is collected, complex impedance information is extracted and fitted to a randall equivalent circuit model, and charge transfer resistance and interface capacitance values are obtained; and the parameter deviation degree is calculated according to the charge transfer resistance of the current detection period and historical reference, so as to determine the fatigue damage condition of the local area.

The application discloses a kind of lithium battery's residual life prediction method, belong to battery life prediction technical field.The application first divides lithium battery charging process into constant-current section, transition section and constant-voltage section, collects voltage and current signal in each section, obtains equivalent transient impedance spectrum by Fourier transform, and calculates interface aging factor based on charge transfer resistance, ohmic resistance and double-layer capacitance;Then respectively extract the features in each section to form the feature vector in each section, derive to obtain the feature vector between sections, splice the three feature vectors in each section corresponding to similar data and two feature vectors between sections to form feature splicing vector;Finally, using the feature weighted distribution type BP model, the feature splicing vector of equivalent transient impedance spectrum and interface aging factor is processed, and the residual life prediction value is output.The application improves the prediction accuracy significantly by charging segmented feature extraction, inter-feature extraction and weighted model optimization.

The invention relates to the technical field of supercapacitor preparation, in particular to a (NiCo) Se2 / CoFe2Se4 composite electrode, a preparation method and application, and the method comprises the steps: preparing a NiCo precursor solution through Ni salt, Co salt and urea, growing NiCo precursor nanorods on a titanium mesh, and constructing a three-dimensional conductive skeleton; then preparing a Co-FePBA suspension by using Co salt, sodium citrate and K3 [Fe (CN) 6]; the titanium mesh loaded with the NiCo precursor nanorod is soaked in Co-FePBA suspension and aged at the constant temperature, a double-active-component precursor is formed, effective interface chemical bonding is formed, and the charge transfer efficiency can be effectively improved; finally, a (NiCo) Se2 / CoFe2Se4 heterojunction is generated through gas-phase selenylation, charges are redistributed at a heterogeneous interface, a built-in electric field is formed, and electron transfer and ion adsorption are accelerated; according to the method, the reaction kinetics of collaborative optimization of the (NiCo) Se2 and the CoFe2Se4 is realized, the process is simple, convenient, environment-friendly and economical, a feasible scheme is provided for large-scale production, and the problems of compounding of the (NiCo) Se2 and the CoFe2Se4, high charge transfer resistance and poor charge and discharge efficiency in the prior art are solved.

A negative electrode is provided. The negative electrode comprises a negative current collector and a negative active material layer arranged on the negative current collector. The anode active material layer includes an electrochemically active material, a dispersant polymer binder, an adhesive polymer binder, and a conductive filler. The electrochemically active material includes graphite. The dispersant polymer binder has amphiphilic properties, including a hydrophobic domain and a hydrophilic domain that stabilizes hydrophobic carbon in water. The adhesive polymer binder has a glass transition temperature and can provide flexibility, durability, and cohesive strength between carbon particles. The conductive filler includes a conductive carbon that reduces pore channels and charge transfer resistance at the binder active material interface.

A sodium-ion solid-state electrolyte and a preparation method therefor, and an all-solid-state sodium-ion battery. The electrolyte comprises a substrate and an interface protection layer, wherein the interface protection layer covers a surface of the substrate; the substrate is a polymer electrolyte; the interface protection layer is a metal; and the metal comprises at least one of Sn, Zn, In, Sb, Bi and Ge. By covering the surface of the substrate with the metal source serving as the interface protection layer, a stable metal thin layer interface is formed by means of the alloying of sodium and the metal source, which metal thin layer interface can effectively prevent the growth of sodium dendrites, reduce damage to the sodium-ion solid-state electrolyte in the cycling process of a battery, improve the interfacial wettability and reduce the interfacial charge transfer resistance, thereby improving the interface stability of a sodium metal negative electrode and the solid-state electrolyte, and therefore a stable long-cycle all-solid-state sodium-ion battery is obtained.

The invention discloses a preparation method of a three-dimensional MXene / carbon quantum dot hybrid material for a negative electrode of a high-performance lithium ion battery, which comprises the following steps: by taking cationic polylactic acid (CPLA) microspheres as a self-sacrifice template, uniformly coating the surface of CPLA with negatively charged MXene nanosheets through electrostatic self-assembly in deionized water to form a composite microsphere precursor; then vacuum freeze drying and high-temperature heat treatment are carried out, CPLA is decomposed, carbon quantum dots are induced to be generated in situ, the hybrid material composed of the three-dimensional MXene hollow microspheres and the carbon quantum dots is obtained, and the carbon quantum dots are of a highly-graphitized ordered structure and are stably attached to the surfaces and the interlayers of the hollow microspheres. When the material is used as a negative electrode of a lithium battery, the unique three-dimensional porous structure and surface characteristics of the material form a synergistic effect, so that the specific surface area is effectively increased, the charge transfer resistance is reduced, the stability of an ion transmission channel and an electrode structure is optimized, and the reversible capacity and cycle performance of the battery are remarkably improved.

This invention provides an online detection method for effective chlorine concentration using a thin-layer channel electrochemical sensor. The method includes: measuring the charge transfer resistance of the sensor's working electrode using electrochemical impedance spectroscopy; intelligently determining the electrode's contamination state and triggering closed-loop adaptive cleaning; after cleaning, measuring the high-frequency impedance of the solution to obtain real-time conductivity parameters; applying a detection sequence containing at least three different potential steps, simultaneously acquiring the steady-state current, pH value, and temperature of the solution at each potential; correcting the current for conductivity based on the solution impedance; and calculating the molecular hypochlorous acid concentration in real time based on the dissociation equilibrium formula of hypochlorous acid, combined with pH value and temperature. This invention achieves intelligent maintenance of the electrode state and dynamic compensation for solution matrix interference, enabling high-precision and high-stability online detection of the molecular hypochlorous acid concentration, which plays a crucial role in disinfection efficacy.

The application discloses a kind of Pt nanoparticle load Fe-based MOF photocatalyst and its preparation method and application, belong to environmental energy technical field.The preparation method disclosed in the application uses 2-amino terephthalic acid, FeCl3·6H2O and aqueous solution of chloroplatinic acid hexahydrate as raw material, through hydrothermal reaction, Pt nanoparticle is dispersed in situ and loaded NH2-MIL-101 (Fe), reduces interface charge transfer resistance, inhibits the recombination of photo-generated carriers, to further improve the photocatalytic nitrogen fixation activity, using the synergistic effect of NH2-MIL-101 (Fe) composite photocatalyst containing Pt nanoparticle to achieve the purpose of improving the yield of photocatalytic conversion of nitrogen to ammonia, significantly solve the high energy consumption and environmental pollution problem of traditional industrial nitrogen fixation Haber-Bosch method.

The invention relates to the technical field of energy storage material preparation, in particular to a bionic compound eye structure photo-anode and a preparation method and application thereof. The photoanode electrode of the CdS / ZnO / FTO compound eye structure heterogeneous thin film is used as the anode of the photoelectrochemical PEC water decomposition hydrogen production battery, and CdS with the narrow band gap of 2.4 eV is introduced and can be coupled with ZnO to expand visible light absorption, so that the photoelectrochemical PEC water decomposition hydrogen production battery is used for photoelectrochemical water decomposition. This makes it a suitable choice for PEC applications. Besides, a ZnO / CdS heterojunction is formed through coupling of CdS and ZnO, a staggered band gap structure is caused, semicircles of all ZnO / CdS heterostructure films are smaller than exposed ZnO, charge transfer resistance is reduced through formation of the heterostructure, transfer of photo-induced electron holes from CdS to ZnO is effectively accelerated, recombination at an interface is also remarkably inhibited, and therefore PEC efficiency is improved.

The application relates to the technical field of lithium ion batteries, in particular to a halide electrolyte modified low-impedance positive electrode and a preparation process and application thereof; the existing lithium ion battery has the problem of high impedance of the positive electrode material; the preparation method uses carbon-coated aluminum foil as the positive electrode current collector, has low contact impedance and high adhesion, reduces the charge transfer resistance and the battery internal resistance, and improves the rate performance and the cycle performance of the battery; the positive electrode active material is added, C6H 12 O6*H2O is used for carbon coating to improve the electronic transmission capacity of lithium iron phosphate, titanium-vanadium co-doping is used for synergistically improving the electronic conductivity and reducing the electronic conduction impedance; halide solid electrolyte coating lithium iron phosphate inhibits the side reaction and reduces the interface impedance; carbon nanotube coating inhibits particle agglomeration and reduces the charge transfer impedance; the modified conductive agent and the modified binder are added, so that the lithium ion battery has higher cycle stability, higher electrochemical activity and lower impedance.

The invention relates to the technical field of bioelectricity signal monitoring, in particular to an implantable biofilm wireless monitoring sensor and system based on AgCl / Ag impedance conversion, and the system comprises an anode integration module, a cathode verification module, a frequency analysis module, a closed-loop regulation and control module and a packaging state evaluation module. According to the method, by directly collecting the current of the closed-loop circuit of the implant and the charge transfer resistance of the biological membrane, original interface information is provided for subsequent analysis, the change rate of the resistivity of the silver chloride is detected, the resonant frequency deviation of the silver / silver chloride antenna is synchronously measured, a high-sensitivity anomaly recognition mechanism is constructed, and the early-warning capability of interface instability or material degradation in the early stage is improved; extracting a circuit phase angle and an antenna Q value after abnormity identification, calculating a frequency compensation coefficient by applying frequency domain least square fitting, controlling a silver chloride / silver conversion rate, optimizing wireless signal transmission, monitoring a packaged water vapor transmission rate and an ion permeation flux, and ensuring long-term reliability of implanted equipment.

The invention provides an oxygen evolution reaction catalytic electrode and a preparation method and application thereof, and relates to the technical field of water electrolysis hydrogen production. The electrode comprises a carrier, a high-entropy tungsten-based oxide is loaded on the carrier, the chemical general formula of the high-entropy tungsten-based oxide is MaFebWa + bO4 (a + b)-x, and M comprises any four or more elements of V, Cr, Mn, Co, Ni and Cu; the range of a: b is (8-10): (1-2), and x is more than or equal to 0 and less than or equal to 0.5 (a + b). The special electron orbital structure of tungsten enables electrons to efficiently migrate in crystal lattices, reduces charge transfer resistance, accelerates an electrode reaction kinetics process, can drive the reaction to proceed under low overpotential, and generates relatively high current density. Tungsten and surrounding atoms form strong chemical bonds, chemical erosion and dissolution are effectively inhibited, and long-acting and stable operation of the electrode is guaranteed.

The invention relates to the technical field of electrolytic bath management, and discloses a fault classification method and system for an anion exchange membrane electrolytic bath, and the method comprises the steps: collecting an excitation response signal generated after an AC disturbance signal is applied to a to-be-classified anion exchange membrane electrolytic bath, and the cross concentration of hydrogen in oxygen; the alternating current disturbance signal is set to be formed by compounding a high-frequency sine wave and a low-frequency sine wave; obtaining a first ohmic resistance according to a high-frequency excitation response signal in the excitation response signals; obtaining charge transfer resistance according to a low-frequency excitation response signal in the excitation response signals and the first ohmic resistance; and based on a pre-trained fault diagnosis model and a pre-constructed fault rule base, analyzing the first ohmic resistance, the charge transfer resistance and the cross concentration to obtain a fault classification result. According to the method, the health condition of each specific assembly of the anion exchange membrane electrolytic cell is predicted, the application range is wide, and the fault classification result is more accurate.

This invention relates to the field of lithium-ion battery technology, specifically to a lithium iron phosphate cathode sheet, its preparation method, and its application, addressing the problems of high resistance, low conductivity, and poor peel strength in existing lithium iron phosphate cathode materials. The preparation method uses carbon-coated aluminum foil as the cathode current collector, which has low contact resistance and high adhesion, reducing charge transfer resistance and battery internal resistance. Modified lithium iron phosphate is used as the cathode active material, providing a small amount of nickel ions into the lithium iron phosphate crystal lattice, creating special structural defects within the crystal and improving the conductivity of lithium iron phosphate. By adding modified conductive agents and modified binders, it achieves excellent cycle stability, improving battery conductivity, rate capacity, and reducing charge transfer resistance.

The invention discloses a tin-carbon composite coated silicon-based silicon alloy nanofiber material for a negative electrode of a lithium battery, the silicon alloy nanofiber material takes a silicon-based material as an inner core, the tin-carbon composite material coats the silicon-based material to form a layer of shell, and the silicon alloy nanofiber material is of a hollow porous structure; the silicon-based core material is coated with the composite tin-carbon material, so that the conductivity of the silicon alloy nanofiber material can be improved, and remarkable volume expansion generated during lithiation of the active particles can be relieved. And the improved conductivity is also beneficial to accelerating the transmission of lithium ions and electrons in an electrode material and at an electrode / electrolyte interface, and reducing the charge transfer resistance, so that the electrochemical reaction kinetics of the electrode is improved.

The invention discloses high-adhesion moisture power generation hydrogel, a preparation method thereof and application of the high-adhesion moisture power generation hydrogel in a flexible moisture power generation device, and belongs to the technical field of intelligent wearing and flexible sensing. The problems of poor output performance, poor mechanical performance and the like caused by unstable contact between a hydrogel layer and an electrode layer in an existing hydrogel moisture generator are solved. According to the invention, glycerol is added to weaken a hydration layer around a polymer chain and expose more functional groups, and the adhesion of hydrogel is enhanced, so that the hydrogel and an electrode are more tightly attached, thereby reducing the charge transfer resistance between interfaces, and greatly improving the output current of a device, which is up to 141 [mu] A.cm <-2 >; in addition, the strong interface adhesion enables the stress distribution of the sandwich structure device to be more uniform, interface failure caused by local stress concentration is avoided, and the electrical performance of the moisture power generation device is enhanced.

The application provides a lithium-rich lithium manganate, a preparation method and application thereof, and belongs to the field of lithium batteries. The application provides a preparation method of the lithium-rich lithium manganate, which comprises the following steps: mixing lithium oxide, manganese monoxide and tetravalent metal oxide, and then sintering to obtain the lithium-rich lithium manganate. The introduced tetravalent metal ions can improve structural stability, improve cycle performance, increase the average valence of transition metal oxides, inhibit cation mixing and irreversible phase transition (such as H2-H3 phase transition of nickel-rich materials and Jahn-Teller distortion of manganese-based materials) in the charging and discharging process, thereby significantly improving the long cycle stability of the material. In addition, the electronic and ionic transport kinetics can be optimized, and the rate performance can be improved. The introduction of tetravalent metal can adjust the electronic structure of the material, reduce the band gap, and improve the electronic conductivity of the material, thereby reducing the charge transfer resistance and improving the large-current charging and discharging performance.

The present invention relates to a process for fabricating an electrochemical device based on praseodymium-doped nickel-ferrite nanoparticles and an electrochemical device thereof. The nickel ferrites are synthesized using solution combustion method, with praseodymium doping concentrations varying from 0 to 0.02. The prepared nanoparticles are characterized for thorough analysis of their structural, morphological, and electrochemical properties, wherein a three-electrode system is developed for evaluation of electrochemical performance of the prepared nanoparticles. The results showed that optimal Pr-doping enhanced both the electrical conductivity and charge storage capacity of the material, wherein the sample with 0.01 Pr-doping (NP-3) exhibited the highest specific capacitance of 69.2 F / g at a current density of 0.1 A / g, with a low charge transfer resistance of 0.30 Ω, making it suitable for energy storage devices.

The application discloses a preparation method of a lithium iron phosphate battery, and comprises the following steps: step one, mixing lithium hydroxide monohydrate, iron phosphate and glucose, and then manually wet grinding the mixture in a agate mortar, and drying the mixture after grinding to obtain a mixed powder; step two, placing the mixed powder into a tube furnace, and performing high-temperature solid-phase synthesis under an argon atmosphere to obtain lithium iron phosphate, and then grinding and sieving the lithium iron phosphate to obtain lithium iron phosphate powder; and step three, stirring and mixing the lithium iron phosphate powder, a conductive agent, a binder and N-methyl pyrrolidone, then coating the mixture on an aluminum foil, cutting the mixture after drying to obtain a positive electrode sheet, and then assembling the positive electrode sheet into a battery in a glove box. The material synthesized by the application has high specific discharge capacity, small charge transfer resistance, strong lithium ion transmission capacity, better reaction kinetics and chemical reversibility of the electrode, maximum peak current and large electric capacity.

The invention discloses a PTFE anion exchange membrane-based biological fuel cell, which comprises an anode chamber, a cathode chamber, an anion exchange membrane and an external circuit system, the anion exchange membrane is a PTFE membrane grafted with quaternary ammonium groups and is arranged between the anode chamber and the cathode chamber, the anode chamber is internally provided with an anode, an anolyte and anaerobic sludge, the anode is attached with anaerobic electrogenesis microorganisms, and the cathode chamber is provided with an anode and an anode liquid. The anaerobic electrogenesis microorganisms decompose organic matters in the anode chamber and generate H < + >, CO2 and electrons; a cathode, a salt buffer solution and O2 are arranged in the cathode chamber, the cathode is conductively connected with the anode through an external circuit system, and OH <-> in the cathode chamber is transferred into the anode chamber through the anion exchange membrane. The biological fuel cell provided by the invention adopts the PTFE membrane grafted with quaternary ammonium groups as the anion exchange membrane, so that OH <-> in the cathode chamber is transferred into the anode chamber through the anion exchange membrane to maintain pH balance of the anode chamber, reduce ion deposition on the surface of the cathode and reduce charge transfer resistance, thereby obtaining higher power density and coulombic efficiency.