10504 results about "Electronic conductivity" patented technology

The invention discloses a battery monomer, a battery device and a power utilization device. Each battery monomer comprises a positive pole piece, a negative pole piece and an electrolyte; the lithium ion conductivity of the electrolyte is greater than or equal to 10 mS / cm; the negative electrode plate comprises a negative electrode current collector and a negative electrode film layer arranged on at least one side of the negative electrode current collector, the negative electrode film layer comprises a negative electrode active material, the negative electrode active material comprises a core part and a coating layer at least partially coating the surface of the core part, the core part comprises graphite, and the coating layer comprises graphite. The concentration ratio (R90-R10) / R50 of an R value is less than or equal to 2.3 in an R value cumulative distribution curve obtained by the negative electrode active material in a surface scanning mode of a laser microscopic confocal Raman spectrometer.

The invention discloses a battery monomer, a battery device and a power utilization device. Each battery monomer comprises a positive pole piece, a negative pole piece, electrolyte and an isolating membrane arranged between the positive pole piece and the negative pole piece; the positive pole piece comprises a positive pole current collector and a positive pole film layer arranged on at least one side of the surface of the positive pole current collector, the positive pole current collector comprises a positive pole current collecting part and a positive pole lug arranged on at least one side of the side surface of the positive pole current collecting part, and the width of the positive pole current collecting part is 62-98 mm; the size of the positive electrode film layer is 63mm to 90mm along the width direction of the positive electrode current collecting part; and the lithium ion conductivity of the electrolyte is 10 mS / cm to 25 mS / cm.

The present invention provides a composite binder for a sulfide solid-state battery, a preparation method thereof and an application thereof, wherein the composite binder comprises a binder A, a binder B and a solvent, wherein the mass ratio of the binder A to the binder B is (1-10):(5-1), and the mass ratio of the total mass of the binder A and the binder B to the solvent is 1:(10-100). The present invention adopts a binder having a polar functional group and a low-polarity / non-polar binder for combination, thereby making the prepared composite binder have good compatibility with the sulfide solid electrolyte, that is, it does not affect the ionic conductivity of the sulfide solid electrolysis, and at the same time makes the sulfide solid electrolyte membrane have good mechanical properties and flexibility.

The invention provides a method for measuring the conductivity and the inner diameter of a pipeline based on sweep frequency eddy current. The method comprises the following steps: establishing an eddy current detection device, designing an absolute eddy current detection coil, placing the coil in a metal pipeline, arranging the coil and the pipeline coaxially, introducing alternating current to excite an alternating magnetic field, and inducing eddy current on the surface and the near surface of the pipeline; establishing a metal pipeline eddy current analysis theoretical model, setting coil geometric parameters, and calculating an analysis expression of coil impedance changing along with excitation frequency; calculating the peak frequency and the corresponding phase value of the impedance phase of the coil in a frequency sweep mode, respectively changing the conductivity and the inner diameter of the pipeline, extracting the corresponding peak frequency and phase value, and constructing an inner diameter relation model based on quadratic curve fitting and a conductivity relation model based on power function fitting; and inverting the inner diameter and the conductivity of the metal pipeline by combining a coil impedance sweep frequency phase measurement result. The method can be used for simultaneously measuring the conductivity and the inner diameter of the pipeline, and is suitable for nondestructive testing and performance evaluation of the metal pipeline.

The invention relates to the technical field of functional materials, in particular to a hollow multi-shell material as well as a low-temperature preparation method and application thereof, which comprises the following steps: 1) mixing a water or alcohol solution of a precursor A with an oil phase to prepare a water-in-oil emulsion, or dispersing the water solution of the precursor A into liquid drops by a spraying method; 2) freezing the emulsion or liquid drops obtained in the step 1) at low temperature to obtain ice template particles containing a precursor A; (3) adding the ice template particles obtained in the step (2) into a precursor B solution, controlling the temperature by a program, melting the ice template, and carrying out precipitation or polymerization reaction on A and B to obtain metal fluoride, carbonate or other hollow multi-shell materials; and 4) using the hollow multi-shell layer obtained in the step 3) as an electrolyte additive. The electrolyte additive can improve the viscosity of an electrolyte, improve the ionic conductivity, stabilize a solid electrolyte interface film, effectively inhibit the growth of lithium dendrites, improve the coulombic efficiency of a battery and prolong the cycle life of the battery.

The invention discloses a power balance control method and system based on a photovoltaic sodium ion battery energy storage system, and relates to the technical field of intelligent power balance. The battery pack state parameters comprise a battery capacity recession rate, a single battery environment temperature gradient and a voltage balance degree at a single battery environment temperature; calculating the thermal management efficiency of the battery pack based on the battery pack state parameters; when the thermal management efficiency of the battery pack is lower than a preset standard threshold value, calculating the ionic conductivity and the rate value of a single battery in the battery pack; and when the ionic conductivity and the rate value of the single batteries in the battery pack are both lower than the preset values, switching the temperature-lost single batteries into a charging mode. By quantifying the thermal management efficiency, the problem that the sodium ion battery cannot be accurately controlled to be stably located at the proper temperature and voltage by the existing battery power balance control technical means is solved.

The invention discloses a carbon-silicon negative electrode material and a preparation method and application thereof, and the preparation method comprises the following steps: S1, carrying out mixed reaction on a lithium source compound, a lanthanum source compound and a titanium source compound to obtain a mixed reactant; mixing the mixed reactant with a carbon source compound, and dispersing and emulsifying to obtain element-doped microspheres; s2, carbonizing the element-doped microspheres in the step S1 to obtain carbides, and activating the carbides to obtain a porous carbon material; and S3, performing silicon deposition on the porous carbon material in the S2 to obtain silicon deposition porous carbon, and performing carbon deposition on the silicon deposition porous carbon to obtain the carbon-silicon negative electrode material. The carbon-silicon negative electrode material disclosed by the invention is high in lithium ion transmission rate, the problem of poor electronic conductivity of silicon is solved, and the electrical property of a battery can be effectively improved.

The invention discloses a preparation method of a high-compaction lithium manganese iron phosphate positive electrode material, which comprises the following steps: placing a manganese source, an iron source and a phosphorus source in deionized water, stirring, carrying out primary high-speed ball milling, carrying out constant-temperature water bath, adding an oxidizing agent, stirring and oxidizing, and drying the slurry to obtain manganese iron phosphate precursor powder; carrying out primary sintering on the ferromanganese phosphate precursor powder to obtain a ferromanganese phosphate primary sintering material; putting the ferromanganese phosphate primary sintering material into deionized water, adding a lithium source and a carbon source at the same time, and performing stirring, secondary high-speed ball milling and drying to obtain lithium ferromanganese phosphate precursor powder; and carrying out secondary sintering on the lithium manganese iron phosphate precursor powder to obtain the high-compaction lithium manganese iron phosphate positive electrode material. The void ratio is well reduced and good carbon coating is realized by means of secondary grinding and secondary sintering, and compared with the prior art, the method has the advantages that good capacity can be maintained, the powder compaction density of the material can be improved, the conductivity can be improved, and the specific surface area of the material can be effectively reduced.

The invention discloses a lithium ion battery internal short circuit fault detection method based on time-frequency fusion, and the method comprises the steps: firstly constructing a fractional order equivalent circuit model fused with an electrochemical aging mechanism, and simulating the paths of conductivity reduction, active material loss and lithium inventory reduction in combination with an aging empirical formula; joint modeling of the aging process and the random internal short circuit is achieved, and multi-cycle voltage and current and electrochemical impedance spectroscopy data are obtained; secondly, extracting time domain features by using a time domain attention enhanced long-short-term memory network, and analyzing frequency domain information by using a multi-scale frequency sensing convolutional neural network; and then weighting and screening two types of modal features through a dynamic gating fusion module, introducing a cross attention mechanism to establish dependency mapping between time-frequency domain features, and finally outputting an internal short circuit fault detection result. The method can solve the problems that in the lithium ion battery aging process, due to lithium dendrite growth, the internal short circuit early fault is high in concealment, and single time-frequency characteristics are difficult to detect, and early high-precision recognition of the internal short circuit fault can be achieved.

The invention relates to the technical field of sodium ion batteries, in particular to a sodium ion electrolyte, a preparation method thereof and a battery. The sodium ion electrolyte comprises an ester solvent, salts and an additive, wherein the ester solvent comprises chain carboxylic ester, chain carbonic ester and cyclic carbonic ester, and the salt comprises sodium salt. The sodium ion electrolyte provided by the invention has high low-temperature conductivity, not only can improve the low-temperature discharge capacity, but also can improve the low-temperature charging capacity, and can widen the charging window of a conventional commercial sodium battery from 0 DEG C to-30 DEG C.

The invention relates to a preparation method and application of a manganese ion doped modified ferric sodium pyrophosphate positive electrode material, and belongs to the technical field of sodium ion battery positive electrodes. The preparation method comprises the following steps: adding a sodium source, a phosphorus source and a carbon source into ethanol, uniformly mixing to form a mixed solution, sequentially adding an iron source and a manganese source into the mixed solution, uniformly mixing to form slurry, and drying the slurry to obtain precursor powder; calcining in a protective atmosphere to obtain a manganese-doped carbon-coated ferric pyrophosphate sodium material; the calcining conditions are as follows: heating to the temperature of 300-350 DEG C at the heating rate of 2-3 DEG C / min, carrying out first-stage constant-temperature calcination for 2-3 hours, heating to the temperature of 500-550 DEG C at the heating rate of 5-8 DEG C / min, and carrying out second-stage constant-temperature calcination for 10-12 hours. By doping the manganese ions, the electronic conductivity and the ion diffusivity of the ferric sodium phosphate pyrophosphate composite material are improved, so that the discharge capacity of the ferric sodium phosphate pyrophosphate composite material at high rate is improved, and the battery has relatively high cycle stability.

The invention discloses a hybrid Lp regularization magnetotelluric two-dimensional inversion method based on adaptive weight, and the method comprises the steps: reading magnetotelluric observation data, carrying out the quadrilateral finite element grid discretization of a whole inversion region, building an inversion grid, and building an initial model and a prior model of the inversion conductivity of the inversion region; based on the initial model and the prior model of the inversion conductivity and the magnetotelluric observation data, constructing a mixed Lp regularization inversion objective function comprising an L1 regularization item, an L2 regularization item and a data fitting item; in an inversion iteration process, adaptively adjusting weight factors of the L2 regularization item and the L1 regularization item; and based on the inversion grid, performing magnetotelluric two-dimensional inversion according to the inversion objective function mixed with Lp regularization, the initial model and magnetotelluric observation data, and outputting optimal model parameters of Gaussian Newton inversion to obtain underground electrical structure information. According to the invention, the resolution and accuracy of the inversion result are improved.

The invention relates to a high-voltage-resistant deep eutectic-based in-situ polymerization solid electrolyte as well as preparation and application thereof. The in-situ polymerization solid electrolyte is obtained through an in-situ polymerization reaction of a precursor solution comprising 30-80 wt% of a deep eutectic solution, 10-50 wt% of a polymerizable monomer, 1-30 wt% of an additive and 0.05-10 wt% of an initiator; the deep eutectic solution comprises a lithium salt and a hydrogen bond donor organic solvent; the hydrogen bond donor organic solvent comprises a nitrile solvent and a non-nitrile solvent; the polymerizable monomer comprises a monomer for free radical-initiated polymerization or ring-opening polymerization; the additive comprises lithium nitrate and fluoroethylene carbonate. The high-voltage-resistant in-situ polymerization solid electrolyte formed by in-situ compounding of an organic framework formed by in-situ polymerization of a deep eutectic solution, an additive and a monomer has the excellent characteristics of wide electrochemical window, high ionic conductivity, high mechanical strength, good flame retardance, wide-temperature applicability and the like, and can be suitable for a high-voltage system of 4.6 V or above; the solid-solid contact problem of a solid-state battery interface is effectively solved, and the side reaction between the electrolyte and the lithium metal negative electrode is reduced.

The invention discloses a single-end open type high-performance magnetic shielding system and a design method thereof. The system is formed by combining a passive magnetic shielding subsystem and an active magnetic compensation subsystem. The passive magnetic shielding subsystem is formed by alternately nesting single-end open type high-permeability and high-conductivity metal barrels, and the structure is beneficial to synchronously improving the shielding capability for full-band magnetic interference; the active magnetic compensation subsystem is composed of a group of axial nonlinear gradient coils, two groups of radial nonlinear gradient coils with orthogonal magnetic fields and a magnetic compensation control circuit, and three groups of magnetic compensation coil windings are obtained based on specific nonlinear distributed magnetic interference reverse design in a single-end open type magnetic shielding barrel; different from conventional shimming and linear gradient coils, accurate compensation of magnetic interference in a working area in the barrel can be realized. According to the invention, the shielding capability of the single-end open type magnetic shielding system is improved, and a required near-zero magnetic environment is provided for extremely weak magnetic measurement.

The invention belongs to the technical field of solid electrolyte materials, and particularly relates to a novel preparation method of a solid electrolyte with high ionic conductivity. The lithium source, the lanthanum source, the niobium source and the fluorine source are mixed, and the solid-phase dispersing agent is added in the mixing process, so that more uniform mixing is facilitated. According to the preparation method, precursor powder is obtained after mixing, then pure-phase LLNOF powder can be directly obtained through one-step sintering, the difficulty that in an existing reported preparation process scheme, a product obtained through two-step sintering has an impure phase is overcome, the preparation process is simple, and batch production and industrialization are facilitated.

Multi-functional composite particulates for a lithium battery, wherein at least one of the composite particulates has a diameter from 100 nm to 50 μm and comprises (a) a polymer electrolyte, comprising from 0.1% to 50% by weight of a lithium salt dissolved or dispersed in the polymer electrolyte; (b) a plurality of primary particles of an anode or cathode active material that are encapsulated by, embedded in, dispersed in, or bonded by the polymer electrolyte having a lithium ion conductivity from 10−8 to 5×10−2 S / cm, wherein the primary particles occupy a weight fraction from 5% to 98%; (c) particles of an inorganic material occupying a weight fraction from 0% to 30% (preferably from 0.1% to 20%); and (d) an electron-conducting additive having a weight fraction of 0% to 30% (preferably from 0.1% to 20%) based on the total weight of the composite particulate.

The invention belongs to the field of sodium ion batteries, and particularly discloses a positive electrode material and a preparation method and application thereof. The positive electrode material is carbon nitride coated fluorine-doped pyrophosphate sodium manganese iron phosphate, the chemical formula of the positive electrode material is NaaFe3-bMnb (PO4-x) 2F4xP2O7 / C3N4, a is larger than or equal to 3.95 and smaller than or equal to 4.1, b is larger than or equal to 0.3 and smaller than or equal to 2.4, and x is larger than or equal to 0.005 and smaller than or equal to 0.05. The sodium ferromanganese pyrophosphate is subjected to fluorine doping and carbon nitride coating, so that the electronic conductivity and the structural stability of the sodium ferromanganese pyrophosphate can be improved, the capacity of the sodium ferromanganese pyrophosphate can be well exerted, and the capacity and the voltage platform of the sodium-ion battery are improved.

Provided are electrochemical cells with an aversive coating covering 2% to 50% of an area of an exterior surface of at least one terminal to deter children from eating the electrochemical cells. Described are compositions and methods for applying aversive coatings to specific locations of electrochemical cell terminals.

The invention discloses a phosphonic acid-based metal organic framework solid electrolyte as well as a preparation method and application thereof, and belongs to the technical field of solid electrolyte materials. The method comprises the following steps: mixing a metal salt, an organic phosphonic acid ligand and an organic solvent, carrying out a coordination reaction, and treating to obtain MOF powder; heating and activating the MOF powder to obtain activated MOF powder; the method comprises the following steps: mechanically grinding lithium salt and MOF powder to form a mixture, heating to enable the molten lithium salt to permeate and fill MOF channels, and cooling to obtain solid electrolyte powder. The ionic conductivity of the solid electrolyte at 30 DEG C reaches 1.01 * 10 <-4 > S cm <-1 >, and the solid electrolyte is kept stable in a 4.4 V high-voltage window. The symmetrical battery based on the phosphonic acid-based MOF solid electrolyte can stably operate, and shows excellent compatibility and stability of the electrolyte and a lithium metal negative electrode. The method has the advantages of simple operation, cheap and easily available components, and is expected to be suitable for large-scale preparation.

The invention relates to a polymer binder for a sulfide solid-state battery as well as a preparation method and application of the polymer binder. The binding agent is formed by copolymerizing vinyl triethoxy silane, 4-vinyl phenylboronic acid lithium and styrene. Silane groups are introduced, the interface adhesiveness with sulfide electrolyte is enhanced through the coupling effect of the silane groups, meanwhile, water in a system is consumed through a condensation reaction, and the water content of an electrolyte membrane is reduced; 4-vinyl phenylboronic acid lithium provides dissociation lithium ions, the ionic conductivity of the binder is improved, and the negative influence on the conductivity of sulfide electrolyte is reduced; the styrene group improves the solubility of the binder in a non-polar solvent. The binder can be dissolved in solvents such as toluene, xylene and the like, and is mixed with sulfide electrolyte to form a film through a wet coating process, and the process compatibility is high. The binder disclosed by the invention has the characteristics of high cohesiveness, ionic conductivity and low water content, and the interface stability and electrochemical performance of the sulfide solid-state battery can be remarkably improved.

The invention discloses a conductivity measurement compensation method and system based on temperature field distribution modeling, and the method comprises the following steps: 1), building a to-be-measured medium temperature field model which is used for describing the temperature distribution in a medium; 2) establishing a conductivity temperature compensation model; 3) coupling the temperature field model and the conductivity temperature compensation model, and establishing a conductivity measurement compensation equation; 4) solving the conductivity measurement compensation equation to obtain compensated conductivity distribution; and 5) receiving data of the temperature sensor in real time, dynamically updating boundary conditions and initial conditions of the temperature field model, inputting temperature field distribution obtained by calculation into the conductivity compensation model, and compensating a conductivity measurement result in real time. According to the method, the influence of the temperature change on the conductivity is more accurately compensated by simulating the temperature distribution of the medium, the method adapts to the environment condition of rapid change, and the measurement precision of the conductivity can be obviously improved in the scene of large temperature gradient or rapid change.

The invention discloses a light-operated reconfigurable metasurface for full-space terahertz wave beam regulation and control, solves the problem of how to provide ubiquitous full-space wave beam coverage for multi-user wireless communication application, and belongs to the field of artificial electromagnetic metamaterials. The super subunit comprises N super subunits which are arranged periodically, each super subunit comprises 4 * 4 identical coding units, corresponding codes are '0' and '1' respectively when illumination exists or not, and the phase response difference of the two coding units at 0.7 THz is 180 degrees. Each super subunit comprises five layers, the third layer is used for switching between reflection and transmission, when vanadium dioxide is in a medium state, the super surface is in a transmission mode, and when vanadium dioxide is in a metal state, the super surface is in a reflection mode. The first layer, the second layer, the fourth layer and the fifth layer are used for controlling the amplitude and the phase of the total-space terahertz wave, the conductivity of the photosensitive silicon pattern is changed under excitation of light with different intensities, the phase of the total-space terahertz wave beam is effectively modulated, and one-bit terahertz information coding is achieved.

The invention discloses a silicon negative electrode material as well as a preparation method and application thereof, and belongs to the technical field of lithium ion batteries. The silicon negative electrode material comprises a silicon material substrate and a coating layer coating the surface of the silicon material substrate, the coating layer comprises cyclized polyacrylonitrile and a fast ion conductor. According to the silicon negative electrode material provided by the invention, a uniform cyclized polyacrylonitrile and fast ion conductor coating layer is constructed on the surface of a silicon material matrix. The good electronic conductivity and elasticity of the cyclized polyacrylonitrile and the excellent ionic conductivity of the fast ion conductor are beneficial to buffering the volume expansion of the silicon carbon material, accelerating the lithium ion transmission kinetics and effectively improving the rate capability of the negative electrode material; the cyclized polyacrylonitrile has high chemical stability and strong compatibility with the silicon material and the sulfide solid electrolyte, and is used as a buffer layer between the silicon material and the sulfide solid electrolyte to avoid direct contact between the silicon carbon material and the sulfide solid electrolyte, inhibit interface side reaction and effectively improve the cycle stability of the battery.

The invention relates to the technical field of integrated circuit manufacturing, in particular to a precise electroplating control system and method for an electroplated layer of a double-layer circuit board, and the method comprises the steps: building a multi-physical field coupling simulation model, and simulating the internal current density and ion concentration distribution of a via hole; constructing a mapping relation between the current density and the side wall electroplating thickness based on a simulation result, and predicting the electroplating thickness; through thickness prediction feedback, a time sequence adjustable pulse current control strategy is designed, the pulse amplitude, the duty ratio and the on-off period are dynamically adjusted, and current distribution optimization is guided; the state of the electroplating process is sensed in combination with real-time monitoring and analysis of multi-source parameters of electrode potential, conductivity and fluid velocity; and based on the prediction model and the real-time parameters, adjusting the pulse waveform and the time sequence through closed-loop compensation. According to the method, the uniformity and controllability of the thickness of the electroplated layer on the side wall of the via hole can be remarkably improved.

The invention discloses a difunctional filler synergistically enhanced polymer solid electrolyte and a solid-state battery, and belongs to the field of solid-state batteries. The electrolyte adopts a polymer matrix, a lithium salt and two functional fillers: the first filler has a high dielectric constant, and can accelerate dissociation of the lithium salt, fix negative ions of the lithium salt and improve the transference number of lithium ions under the action of self polarization; and the second filler has high electrochemical window and ionic conductivity, can inhibit high-voltage decomposition, and is adaptive to a high-voltage positive electrode material. Through cooperation and balance design of the two kinds of filler, ion transmission, interface stability and high-pressure compatibility can be considered at the same time. In addition, the invention further designs a composite negative pole piece, the surface of the negative pole piece is coated with the solid electrolyte, and the ion transmission kinetics in the pole piece can be remarkably improved. On the basis, the invention develops a high-performance solid-state battery which is excellent in electrochemical performance and can play an important role in the fields of consumer electronics, electric automobiles, energy storage systems, low-altitude flight and the like.

The invention relates to an inorganic sodium ion solid electrolyte material screening method, system, equipment and medium, sodium-based inorganic compound data is extracted from an open source material database, and a candidate library is formed through preliminary screening; constructing a regression model by using training data of the dynamic solid electrolyte database, and optimizing and selecting an optimal machine learning model; inputting the preliminary candidate library into the model, and predicting and screening out a preliminary screening material of which the ionic conductivity is higher than a first threshold value; performing simulation calculation on the primarily screened material based on a first principle, simulating sodium ion diffusion tracks at different temperatures by using de novo molecular dynamics, calculating a diffusion coefficient, and extrapolating the diffusion coefficient to ionic conductivity at room temperature; and comparing the electrical conductivity predicted by machine learning and the electrical conductivity simulated by the first principle, and selecting a material of which the two electrical conductivity are both higher than a second threshold value and the migration energy barrier is relatively low as the optimal sodium ion solid electrolyte. Compared with the prior art, the method can efficiently and accurately screen out the high-performance sodium ion solid electrolyte material.

The invention belongs to the technical field of solid-state lithium batteries, and relates to a fluorinated double-salt cross-linked solid-state electrolyte adaptive to a lithium-free negative electrode, a solid-state lithium battery and a preparation method thereof.The preparation method comprises the steps that double-lithium salt is dissolved in a fluorinated solvent to obtain an electrolyte, then a monomer, a cross-linking agent and an initiator are added, the mixture is stirred to be uniform to obtain a precursor solution, and the precursor solution is prepared; and assembling the precursor solution, a positive electrode, a negative electrode and a solid-state electrolyte composite diaphragm into a battery, and performing gradient polymerization to form the solid-state lithium battery. According to the invention, the ionic conductivity of the solid electrolyte is more than 5 * 10 <-4 > S / cm and the oxidation potential of the solid electrolyte is more than 5.8 V by adopting a fluorinated solvent consisting of fluorinated carbonate and fluorinated carboxylate and a double-lithium-salt synergistic system and combining an in-situ interface fusion technology, so that the solid electrolyte can be matched with a 4.8 V high-voltage lithium-rich manganese-based positive electrode and a lithium-free negative electrode; and the energy density and the safety of the solid-state lithium battery are improved. The electrolyte scheme is low in cost, high in safety and good in positive and negative electrode matching performance, can be compatible with an existing battery production line, and is convenient for large-scale production.

The invention provides a double-layer polymer solid electrolyte, a preparation method thereof and a lithium ion battery, and belongs to the technical field of solid electrolyte manufacturing. The first polymer solid electrolyte layer comprises the following raw materials in parts by weight: 4-30 parts of a first reactive monomer A, 5-25 parts of a first reactive monomer B, a first cross-linking agent, a first photoinitiator, a first lithium salt, 1-20 parts of a first carbonic ester plasticizer and 20-45 parts of a nitrile plasticizer; the second polymer solid electrolyte layer comprises the following raw materials in parts by weight: 4-30 parts of a second reactive monomer A, 5-25 parts of a second reactive monomer B, a second cross-linking agent, a second photoinitiator, a second lithium salt, 1-35 parts of a second carbonic ester plasticizer and 10-35 parts of a fluorine-containing plasticizer; the double-layer polymer solid electrolyte has the advantages of relatively high ionic conductivity and compatibility of a high-voltage battery positive electrode and a low-voltage lithium metal negative electrode, so that the corresponding battery has relatively excellent cycle performance and relatively high capacity.

The invention provides a high-frequency eddy current-based metal pipeline conductivity measurement method, which comprises the following steps: designing an absolute eddy current sensor, positioning a sensor coil on the inner side of a metal pipeline and coaxially arranging the sensor coil and the pipeline, and introducing high-frequency alternating current into the coil to generate eddy current; establishing a simplified high-frequency eddy current detection analysis theoretical model, and setting geometric dimensions of a sensor and a pipeline; a Bessel function and a spatial resolution expression are used for analyzing the relation between the real part of the eddy current impedance change under high-frequency excitation and the conductivity of the pipeline; setting the conductivity of the metal pipeline according to the analysis result, and fitting the relation between the impedance change and the conductivity through a power function; and according to a coil impedance measurement result, combining the fitted power function curve, and performing inversion to obtain the actual conductivity of the metal pipeline. According to the invention, the conductivity of the metal pipeline can be effectively measured.

The invention provides a composite solid-state electrolyte membrane and a preparation method and application thereof, and belongs to the field of lithium battery solid-state electrolytes.The preparation method comprises the steps that solid-state electrolyte powder and carbon precursor powder are pressed into a membrane and then subjected to gradient heating calcination, and a three-dimensional framework porous ceramic membrane is obtained; uniformly mixing a lithium salt, a polymer monomer and an initiator to prepare a polymerization solution; and dropwise adding the polymerization solution onto the three-dimensional skeleton porous ceramic membrane, and carrying out thermal polymerization to obtain the composite solid electrolyte membrane. Aiming at the inorganic solid electrolyte, the composite solid electrolyte membrane with high ionic conductivity and good interfacial compatibility is obtained in a mode of in-situ construction of the composite solid electrolyte membrane, and the problems that the inorganic solid electrolyte is low in ionic conductivity, poor in interface contact and not resistant to high pressure are effectively solved.