11 results about "Ohmic Resistance" patented technology

This invention belongs to the field of electrochemical deoxygenation technology, specifically relating to an electrochemical oxygen atmosphere control system and method. The system, from bottom to top, includes a porous bottom cover, a first hydrophobic and breathable membrane, an oxygen-consuming cathode, a liquid-conducting diaphragm, an oxygen-evolving anode, a second hydrophobic and breathable membrane, and a porous top cover. Each component layer forms a zero-gap contact through the clamping force of the outer shell, enabling the device to achieve an ultra-thin thickness. The liquid-conducting diaphragm has a transverse liquid-conducting groove extending to the external electrolyte chamber, utilizing capillary action to achieve rapid electrolyte replenishment and eliminate local hot spots. Through the coupling design between the hydrophobic and breathable membrane and the electrode interface, oxygen generated by the oxygen-evolving anode directly penetrates and overflows in the form of gas molecules, effectively suppressing bubble formation and accumulation in traditional electrolysis processes, and significantly reducing the ohmic resistance of the interface and operating energy consumption. This invention features an extremely thin structure, high reaction efficiency, and no bubble interference, making it suitable for precise oxygen concentration control in spaces such as refrigerators and precision storage environments.

Instrumented nut, clamping sleeve, clamping device and method for tightening such a nut. The invention relates to an instrumented metal nut (10b) comprising a tubular body having a polygonal drive surface (14). The nut comprises, on at least one annular portion (34) of the outer surface: an electrically insulating layer (36) applied to the annular portion; a piezoresistive conductive polymer (38) whose ohmic resistance varies according to a stress exerted during tightening of the nut on a threaded fastener, said conductive polymer being applied to the electrically insulating layer; and at least two electrodes (40). Figure for the abstract: Figure 2

This application discloses a method and apparatus for calculating the ohmic resistance of a planar solid oxide fuel cell stack, relating to the field of fuel cell and electrolysis device technology. The method includes: obtaining the geometric structural parameters, material conductivity parameters, and current collector structure parameters of a single cell in the planar solid oxide fuel cell stack; based on the current collector structure parameters, performing an equivalent reconstruction of the current conduction path in the electrodes to establish an equivalent current conduction model including the influence of the current collector path; based on the equivalent current conduction model, calculating the equivalent ohmic resistance of the single cell under operating conditions according to the geometric structural parameters and the material conductivity parameters; and using the equivalent ohmic resistance of the single cell as the ohmic resistance of the planar solid oxide fuel cell stack. This application can accurately calculate the ohmic resistance, improving the accuracy of stack structure optimization and performance analysis.

This invention relates to the field of fuel cell technology and discloses a fuel cell impedance attribution method based on a physically interpretable impedance model. The method includes: performing impedance decomposition on the physically interpretable impedance model to obtain multiple sub-impedances of the fuel cell, including ohmic resistance, anode impedance, cathode activation impedance, cathode mass transfer diffusion impedance, and cathode mass transfer convection impedance; obtaining the frequency corresponding to the minimum value of the imaginary part of each sub-impedance, the inverse of the minimum value of the imaginary part, and the difference between the low-frequency real part value and the high-frequency real part value, as characteristic frequencies, imaginary peak values, and equivalent resistances; plotting the Nyquist plot, Bode plot, resistance ratio of the sub-impedance's equivalent resistance to the total equivalent resistance, and frequency-peak plot reflecting the relationship between the characteristic frequency and the imaginary peak value for each sub-impedance, to determine the contribution of each sub-impedance to the physically interpretable impedance model, thus realizing impedance attribution analysis under the physically interpretable impedance model.

The invention relates to a method for charging a battery (B) comprising the steps of determining an initial battery state of the battery (B), determining a resting voltage and a resting potential of an anode from a lookup table (LUT) or from a model, briefly applying a current from a lookup table (LUT) or from the model or an overvoltage corresponding to the resting potential of the anode multiplied by a factor, determining an internal resistance via an overvoltage and the current, and reading an effective ohmic resistance (R). Ohm ) from a lookup table (LUT) or from the model, determining a chemical resistance by subtracting the effective ohmic resistance (R) from the internal resistance. Ohm) is reduced, determining a maximum possible charging current and / or a maximum overvoltage such that the overvoltage of the chemical resistance corresponds to the resting potential of the anode multiplied by the factor, and charging the battery (B) with a current that is less than or equal to the determined maximum possible charging current, and / or with a voltage that is less than or equal to the determined maximum overvoltage added to the resting voltage, until at least one predetermined end condition is reached.

The embodiment of the application provides a parameter identification method and device of a battery equivalent circuit model and a readable storage medium, the method comprises the following steps: obtaining a target direct current resistance of a battery to be measured under a preset temperature and a preset state of charge in a first working condition; obtaining a first resistance value of the battery under the preset temperature and the preset state of charge in a second working condition, wherein the first resistance value represents the resistance value of the ohmic resistance of the battery; determining a target constraint condition according to the target direct current resistance and the first resistance value, wherein the target constraint condition is used to constrain the relationship between the target direct current resistance, the first resistance value and the resistance values of all resistances to be identified in the equivalent circuit model; and performing parameter identification on the equivalent circuit model corresponding to the battery according to the target constraint condition and a preset identification algorithm to obtain target resistance and capacitance parameters of the equivalent circuit model.

The application discloses a battery life cycle state monitoring and power estimation system and method, and the system comprises a cloud big data platform and an intelligent battery terminal. The cloud platform receives operation data uploaded by the terminal, fits a personalized equivalent circuit model parameter table, predicts a maximum available capacity of the battery, generates a strategy configuration file and issues the strategy configuration file. An embedded battery management master control unit of the terminal stores a preset noise covariance matrix. The master control unit loads the configuration file, obtains an ohmic resistance, a polarization resistance and a polarization capacitance from the parameter table according to real-time working conditions through interpolation. The master control unit constructs an extended Kalman filter state observer based on the maximum available capacity of the battery, the above parameters and the preset noise covariance matrix. The system performs multi-source fusion processing on collected voltage, current and temperature signals, and outputs a real-time state of charge estimation value.

The application discloses a pipeline anticorrosion layer resistivity calculation method and system, obtains the multi-frequency variable-frequency impedance data of the pipeline anticorrosion layer in a preset low-frequency range; carries out signal-to-noise ratio evaluation on the multi-frequency variable-frequency impedance data to obtain initial impedance spectrum data; carries out Kramers-Kronig relationship validity verification on the initial impedance spectrum data to generate a set of available frequency points; carries out relaxation time distribution analysis on the impedance data corresponding to the set of available frequency points to identify the relaxation time constant; generates a set of candidate equivalent circuit models and model parameter initial values according to the relaxation time constant; carries out complex nonlinear least square fitting on the candidate equivalent circuit models to obtain an optimal equivalent circuit model; extracts an anticorrosion layer ohmic resistance term from the parameters of the optimal equivalent circuit model, and calculates the real value of the anticorrosion layer surface resistivity according to a geometric conversion coefficient. Through the establishment of a multi-frequency joint fitting and resistivity calculation framework, the real value of the output resistivity has consistency and repeatability.

The application discloses a kind of power lithium battery health critical period of retirement fast detection method, including in the process of battery charging and discharging, with preset high frequency sampling period real-time acquisition battery multidimensional state data.The application introduces differential voltage / capacity analysis, ohmic resistance growth rate and voltage relaxation time constant and other sensitive features, accurately capture lithium ion diffusion capacity decline and active lithium loss and other microscopic electrochemical changes, overcome the defect of big accumulated error of traditional ampere-hour integral method in critical period;And realize high-precision SOH estimation under small sample, through output confidence interval, quantification prediction uncertainty, avoid misjudgment caused by data fluctuation, improve the scientific nature of BMS decision, adopt "hard threshold+soft threshold" double threshold determination mechanism, combine SOH attenuation slope and resistance growth rate, accurately identify 80%-85% interval's recession acceleration inflection point, realize from "passive alarm" to "active early warning" change, effectively balance battery use safety and economy.