268 results about "Cell impedance" patented technology

A method for battery power management based on battery nonlinearity characterization and compensation using a nonlinear resistor-capacitor (RC) equivalent circuit model (ECM) may include: measuring a current, a terminal voltage, and a temperature of a battery; implementing the nonlinear RC ECM comprising fixed, logarithmically spaced time constants and current dependent resistances and capacitances; constraining resistances of the nonlinear RC ECM to be nonnegative and performing a nonlinearity characterization procedure using the nonlinear RC ECM configured to characterize variations of a battery impedance with current amplitudes over a range of frequencies and create ECM parameter variations with current amplitudes by fitting impedance variations by nonlinear RC ECMs; performing online estimation of the nonlinear RC ECM using a battery current and a terminal voltage of the battery over time; and modifying the online estimated nonlinear RC ECM using ECM parameter variations to compensate for nonlinearity of the battery.

Understanding a health status and expected remaining lifetime of an EV (electric vehicle) battery is important before repurposing the battery for second life applications. A device for connecting to an unopened EV battery pack via operable coupling to signal and power wiring is disclosed. The device enables access to diagnostic information from the unopened EV battery. The device measures cell and / or module voltages and currents within the battery pack for several different depths of discharge. A self-learning algorithm implemented by the diagnostic device, which uses historical data and diagnostic information from the battery pack, determines a condition of the battery and provide recommended operational conditions for future use of the battery. For example, a degradation slope and expected capacity loss over time can be determined based on measured variations of cell and / or modular voltages and subsequently used, with cell impedance data, to recommend an operational C-rate for the battery pack.

The invention discloses a Fourier transform and S transform combined battery impedance spectroscopy measurement method and device, and aims to improve the precision, speed and reliability of impedance measurement of a battery energy storage system. According to the method, a multi-frequency component excitation signal is generated through a controllable current source, and current and voltage response signals of a battery are synchronously acquired and are respectively input into a Fourier transform module and an S transform module for frequency domain analysis. The Fourier transform module extracts impedance spectrums of low and medium frequency bands, and the S transform module extracts impedance spectrums of medium and high frequency bands through Gaussian window time-frequency analysis. And a data fusion algorithm is adopted to perform composite processing on results of the two modules, including a direct selection method, an arithmetic average method, an amplitude and phase calibration method and a weighted average method, so that smooth transition and optimization between frequency bands are realized, and finally the electrochemical impedance spectrum is generated. Through collaborative analysis of Fourier transform and S transform, parameter optimization and a fusion algorithm, the efficiency and accuracy of impedance spectroscopy measurement are remarkably improved, and the method is suitable for rapid monitoring and diagnosis of the battery state.

The invention provides an intelligent battery sorting method integrating impedance characteristics and deep learning. The method comprises the following steps: acquiring battery impedance data through an electrochemical workstation, drawing an electrochemical impedance spectroscopy (EIS), and extracting impedance characteristics of a medium-frequency region; a 25-dimensional impedance coupling feature space is innovatively constructed, a dual-network differentiated feature selection strategy (IC-GRU) is adopted, a main network selects 12 features with the highest correlation, a boundary expert network selects 10 features with the highest correlation and additionally constructs 5 boundary sensitive features, and finally, the main network selects 12 features with the highest correlation. And establishing an impedance coupling sensing gating circulation unit network to realize accurate prediction of the state of health (SOH). And performing four-stage sorting on the SOH result predicted by the IC-GRU through a random forest algorithm (RF). According to the method, more accurate SOH prediction is realized through deep learning guided by a physical mechanism, the battery pack health state sorting precision and consistency are improved, and an intelligent solution is provided for new energy automobile battery life management.

The invention provides a positive electrode, a lithium battery and a device. The positive electrode comprises a positive electrode current collector and a lithium supplement layer and a positive electrode material layer which are sequentially stacked on at least one side of the positive electrode current collector, the lithium supplement layer contains a first positive electrode lithium supplement agent, the positive electrode material layer contains a positive electrode active material and a second positive electrode lithium supplement agent, the first coulombic efficiency of the first positive electrode lithium supplement agent is less than 30%, and the second coulombic efficiency of the second positive electrode lithium supplement agent is less than 30%. And the second positive electrode lithium supplement agent can be decomposed to generate gas. The first positive electrode lithium supplement agent and the second positive electrode lithium supplement agent are simultaneously introduced into the positive electrode and are arranged in a layered manner, so that the power performance of the battery can be improved while the impedance of the battery is not obviously increased.

The embodiment of the invention discloses a method and a device for controlling charging, charging equipment and a computer readable storage medium, which are used for performing electrochemical impedance spectroscopy analysis by using a second charging protocol and controlling charging through a power management integrated circuit, so that the precision of the electrochemical impedance spectroscopy analysis can be improved. The method comprises the steps of receiving a first communication frame sent by power supply equipment under the condition of detecting that the power supply equipment is inserted and charging is performed by using a first charging protocol; when it is determined that the second charging protocol is used for charging, a first instruction is sent to the power supply equipment according to the first communication frame; acquiring a plurality of first voltage values and a plurality of first current values for charging by using a second charging protocol, wherein the plurality of first voltage values form a first voltage sequence and the plurality of first current values form a first current sequence; and under the condition that at least one of the first voltage sequence and the first current sequence meets a step response condition, calculating a first battery impedance value, and sending a second instruction to the power supply equipment.

The present invention relates to the technical field of lithium ion battery manufacturing, and in particular to an in-situ gel polymer electrolyte and its preparation method and application. It includes: dissolving lithium salt in a mixed organic solvent of 1,3-dioxolane and carbonate organic matter, stirring and mixing evenly under the conditions of room temperature, inert gas protection and a rotation speed of 100 to 1000 rpm; dissolving additives in an electrolyte, stirring under the conditions of room temperature, inert gas protection and a rotation speed of 100 to 1000 rpm; adding an initiator, stirring under the conditions of room temperature, inert gas protection and a rotation speed of 100 to 1000 rpm to obtain an in-situ gel polymer electrolyte. The advantages are: the initiator triggers the in-situ polymerization of 1,3-dioxolane, forms a gel polymer electrolyte in situ in the battery, improves the compatibility of the interface, and reduces the battery impedance; forms a stable interface film, improves the stability of the electrode interface, and improves the room temperature rate performance and low temperature performance of the battery.

The invention provides a positive pole piece, a lithium battery and a device. The positive pole piece comprises a positive current collector as well as a bottom coating and a positive coating which are sequentially stacked on at least one side of the positive current collector, the bottom coating contains a first positive lithium supplement agent, the positive coating contains a positive active material and a second positive lithium supplement agent, the first coulombic efficiency of the first positive lithium supplement agent is less than 30%, and the second coulombic efficiency of the second positive lithium supplement agent is less than 30%. And the second positive electrode lithium supplement agent can be decomposed to generate gas at a voltage greater than the lithium removal potential thereof. The first positive electrode lithium supplement agent and the second positive electrode lithium supplement agent are simultaneously introduced into the positive electrode plate and are arranged in a layered manner, so that many problems caused by independent use of the first positive electrode lithium supplement agent and the second positive electrode lithium supplement agent can be reduced, the lithium supplement utilization rates of the positive electrode plate and the second positive electrode lithium supplement agent are improved, the battery impedance is not obviously increased, and the battery power performance is improved.

The invention belongs to the technical field of batteries, and particularly relates to a sodium ion battery monomer, a positive pole piece, a preparation method thereof and a related device. The sodium ion battery monomer comprises a positive pole piece, the positive pole piece comprises a positive active material and a solid electrolyte interface film at least combined on the surface of the positive active material, and the solid electrolyte interface film comprises one or more cations of Na < + >, Li < + >, K < + > and Ca < 2 + >. The solid electrolyte interface film combined on the surface of the positive electrode active material contains cations such as Na < + >, Li < + >, K < + > and Ca < 2 + >, and the cations can participate in electrochemical reaction of the sodium ion battery, so that reversible capacity is provided, capacity loss generated after the positive electrode active material is passivated is made up, and the cycle performance of the battery is improved. Meanwhile, the solid electrolyte interfacial film containing the cations is beneficial to reducing the impedance of the battery, so that the cycle performance of the battery is further improved.

The invention discloses a secondary battery, and belongs to the technical field of batteries, according to the secondary battery, cyclic sulfate is introduced into an electrolyte, and meanwhile, the content of the cyclic sulfate in the electrolyte, the nuclear magnetic displacement value of central carbon atoms of the electrolyte and the passivation capability of a negative pole piece are cooperatively regulated and controlled, so that the first-effect performance of the secondary battery can be effectively improved; and meanwhile, the low level of battery impedance can also be considered.

The invention relates to the technical field of solid-state battery positive electrode materials, in particular to a double-layer coated halide positive electrode composite material, a preparation method thereof and a solid-state battery. The double-layer coated halide positive electrode composite material comprises a positive electrode material inner core, and a middle layer and an outer layer which sequentially coat the positive electrode material inner core; the material of the intermediate layer comprises a first halide electrolyte with a general formula of LiaMXb; and the material of the outer layer comprises a second halide electrolyte, and the general formula of the second halide electrolyte is LicAGXd or LieAOXf. By utilizing respective advantages of different halide electrolytes, the first halide electrolyte in contact with the positive electrode material is stable to a high-voltage positive electrode, and the second halide electrolyte in contact with the sulfide solid electrolyte layer is stable to a sulfide solid electrolyte; the incompatibility of a high-voltage positive electrode material and a narrow electrochemical window sulfide solid electrolyte can be relieved, the interface side reaction is effectively reduced, the battery impedance is reduced, and the electrochemical performance of a solid-state battery is improved.

The invention provides a positive plate, a battery, a battery pack and electric equipment. The positive plate comprises a positive current collector, a first positive active layer and a second positive active layer, wherein the first positive active layer and the second positive active layer are stacked on at least one side of the positive current collector; the first positive electrode active layer comprises a first positive electrode active material, and the second positive electrode active material comprises a first positive electrode active material and a second positive electrode active material; the first positive electrode active material comprises at least one of a manganese-based positive electrode active material, an iron-based positive electrode active material and a manganese-iron mixed-based positive electrode active material, and the second positive electrode active material comprises at least one of a ternary positive electrode active material, lithium cobalt oxide, lithium nickelate and lithium titanate; the second positive electrode active layer further comprises a second conductive agent, and the second conductive agent comprises at least two linear conductive agents and at least one of a sheet-shaped conductive agent and a point-shaped conductive agent. The positive plate has a special structure and composition, and can effectively improve the impedance increase of the battery and improve the cycle performance of the battery.

The invention provides a decoupling analysis method of a battery medium-high frequency impedance spectroscopy and a battery health diagnosis method, and the decoupling analysis method comprises the steps: building a battery medium-high frequency RQ model, the battery medium-high frequency RQ model comprises at least one RQ link, each RQ link is used for representing an electrochemical process or a conduction characteristic of the battery in a middle-high frequency band in a decoupling manner, and comprises a CPE element and a resistor element which are connected in parallel; and carrying out RQ-DRT transformation on the medium-high frequency impedance spectrum of the battery by using the medium-high frequency RQ model of the battery, and solving to obtain at least one electrochemical process or a characteristic parameter corresponding to a conduction characteristic of the battery in a medium-high frequency band. According to the method used by the invention, the electrochemical process or the conduction characteristic of the high frequency band in the battery impedance spectrum can be quantitatively analyzed in a decoupling manner and can be used as a basis for health diagnosis of the battery.

The invention provides a negative plate, a battery, a battery pack and electric equipment, the negative plate comprises a negative current collector and a negative coating positioned on at least one side surface of the negative current collector, and the negative coating comprises a first coating and a second coating positioned on one side surface, far away from the negative current collector, of the first coating; each of the first coating and the second coating comprises a negative electrode active material; the first coating meets the condition that k1 is larger than or equal to 0.21 and smaller than or equal to 0.65, k1 is the ratio of the particle size D50 of the negative electrode active material in the first coating to the OI value, and the unit of the particle size D50 of the negative electrode active material in the first coating is metered by mu m; the second coating meets the condition that k2 is greater than or equal to 18 and less than or equal to 26, k2 is the ratio of the particle size D50 of the negative electrode active material in the second coating to the OI value, and the unit of the particle size D50 of the negative electrode active material in the second coating is metered by mu m. The battery impedance can be reduced, the quick charging performance of the battery can be improved, and the cycle life of the battery can be prolonged.

The invention provides an SOC estimation method and device for a lithium battery, electronic equipment and a storage medium, and belongs to the technical field of battery management, and the method comprises the steps: obtaining a current model parameter of a pre-constructed battery equivalent circuit model and an SOC estimation value at a previous moment; predicting the terminal voltage of the lithium battery at the current moment based on the current model parameter, the current of the lithium battery at the current moment and the SOC estimated value at the previous moment; and estimating the SOC at the current moment based on the SOC estimated value at the previous moment by adopting an SOC estimation algorithm, and correcting the SOC estimated at the current moment based on the deviation between the predicted terminal voltage and the terminal voltage actually measured at the current moment to obtain the optimal SOC estimated value at the current moment. According to the method, the dynamically updated battery equivalent circuit model parameters are introduced, so that the model can reflect the change of the impedance characteristic of the battery in real time, the terminal voltage prediction error is remarkably reduced, and the SOC estimation precision is improved.

The invention provides a battery impedance analysis method and device, a storage medium and computer equipment. When the battery impedance is analyzed, an EIS test is carried out on a target battery, and various electrochemical behaviors of the battery in the test process are captured through dynamic characteristics in test data, so that a DRT map generated by carrying out DRT analysis on the test data can visually display impedance response time corresponding to different electrochemical processes in a time dimension; after the response interval of each electrochemical process is determined, standard charging and discharging circulation can be carried out on the target battery, DCR testing is carried out on the target battery with a plurality of selected turns in the circulation process, impedance decomposition is carried out on DCR data obtained through testing on the basis of each response interval, and therefore real-time subdivision of overall impedance information is achieved. And finally, carrying out comparative analysis on impedance decomposition data obtained after subdividing each selected number of turns, so as to generate a high-quality impedance analysis result.

The embodiment of the invention provides a lithium battery impedance detection method and system, and relates to the technical field of lithium battery impedance detection, and the method comprises the steps: firstly obtaining high-frequency voltage fluctuation as an AC excitation signal of a lithium battery pack; obtaining a target voltage fluctuation signal and a target current fluctuation signal according to the alternating current excitation signal; performing spectral analysis on the target voltage fluctuation signal and the target current fluctuation signal to obtain a spectral analysis result; calculating a first complex impedance value corresponding to the high-frequency voltage fluctuation according to the spectral analysis result; identifying the current collector corrosion characteristics of the lithium battery pack according to the first complex impedance value and preset time; and according to the current collector corrosion characteristics and a preset battery aging index, distinguishing the aging mechanism of the lithium battery pack. According to the embodiment of the invention, the overall health state of the battery can be comprehensively known, and different aging mechanisms can be distinguished.

The embodiment of the invention provides a fuel cell performance online recovery device and method. Auxiliary hardware, namely a first electric control on-off valve Va1, a second electric control on-off valve Va2 and a third three-way diverter valve Va3, are additionally arranged on an air path of a fuel cell system. The embodiment of the invention provides a fuel cell performance online recovery device and method. Auxiliary hardware, namely a first electric control on-off valve Va1, a second electric control on-off valve Va2 and a third three-way diverter valve Va3, are additionally arranged on an air path of a fuel cell system. In the operation process of the fuel cell, the CVM monitors each single cell of the stack in real time, the impedance detector monitors the impedance of the stack in real time, and according to the comprehensive judgment of the voltage and the internal dry and wet degree of the stack, the first electric control on-off valve Va1, the second electric control on-off valve Va2 and the third three-way diverter valve Va3 are switched to adjust the air humidity and temperature entering the stack for reaction; and the effect of online recovery of the electric pile performance is achieved, so that the waste of time and manpower resources caused by corresponding recovery means operation of pile disassembly due to the degradation of the electric pile performance is avoided.

The invention provides a negative electrode plate, a battery, a battery pack and electric equipment, the negative electrode plate comprises a negative electrode current collector and a negative electrode coating located on at least one side surface of the negative electrode current collector, the negative electrode coating comprises non-coated graphite, and the OI value of the non-coated graphite in the negative electrode coating is 0.06-2. The battery impedance can be reduced, and the cycle life of the battery can be prolonged.

The present invention relates to an apparatus and a method for battery diagnosis based on impedance uncertainty, and the apparatus comprises: a data collection unit for measuring frequency-specific battery impedance and impedance deviation in the entire frequency domain of a battery system assembly (BSA) including at least one battery module; a model construction unit for constructing a diagnostic model for predicting defective states of the battery system assembly by predicting impedance uncertainty on the basis of the impedance deviation and learning both the battery impedance and the impedance uncertainty; and a battery diagnosis unit for measuring diagnostic impedance from the diagnostic BSA at one or more given input frequencies, calculating diagnostic impedance deviation, and, as the result of providing the diagnostic impedance and diagnostic impedance deviation as input to the diagnostic model, generating the result of diagnosing defective state of the diagnostic BSA.

The invention relates to the technical field of electrochemical impedance spectrum testing, in particular to an electrochemical impedance spectrum obtaining method and device based on an energy storage battery, a microprocessor system, a computer readable storage medium and a computer program product. The method comprises the following steps: sampling to obtain a direct-current bus side voltage, and performing direct-current voltage conversion on the direct-current bus side voltage; carrying out single-pole frequency multiplication modulation on the direct current bus side voltage after the direct current voltage conversion to obtain sine voltage disturbance signals under different frequencies; inputting the sinusoidal voltage disturbance signals under different frequencies into the energy storage battery, and sampling to obtain a current response signal of the energy storage battery; according to the sinusoidal voltage disturbance signal and the current response signal, battery impedance under different frequencies is calculated; and acquiring an electrochemical impedance spectrum of the energy storage battery pack according to the battery impedance under different frequencies. By adopting the method, wide-range, low-cost and high-efficiency online electrochemical impedance spectroscopy detection can be realized.

The invention provides a positive pole piece for a sodium ion battery, the sodium ion battery and a device. The positive pole piece comprises a positive current collector, a sodium supplementing layer and a positive coating, the sodium supplementing layer and the positive coating are sequentially stacked on at least one side of the positive current collector, and the sodium supplementing layer comprises a sodium supplementing agent sodium-rich transition metal oxide; and the positive electrode coating contains a positive electrode active material and a sacrificial positive electrode sodium supplementing agent which can be decomposed to generate gas. The two types of positive sodium supplements are introduced into the positive pole piece at the same time and are arranged in a layered manner, so that a plurality of problems caused by independent use of the two types of positive sodium supplements can be reduced, the energy density of the battery is improved, the impedance of the battery is not obviously increased, and the continuous discharge capacity of the battery is improved.

The invention discloses an energy storage battery aging evaluation method and device under an immersed liquid cooling condition, terminal equipment and a storage medium, and belongs to the field of battery testing. The method comprises the steps of obtaining a first active lithium ion loss change rate and a first active substance loss change rate according to a battery voltage and a first battery capacity identification characteristic peak in a to-be-tested battery test, and calculating a battery capacity loss change rate according to a first battery capacity and a second battery capacity before the test; determining a second active lithium ion loss change rate, a second active material loss change rate and a battery impedance change rate based on the electrochemical impedance spectrogram and the pre-test impedance, and determining the battery capacity loss change rate and the battery impedance change rate according to the determined active lithium ion loss, the active material loss, the battery capacity loss change rate and the battery impedance change rate. The resistance, the moisture content and the dielectric loss change rate of the cooling liquid to be measured construct an analytic hierarchy model, the battery aging condition is determined according to the calculated aging evaluation value, and the problem that deviation exists in single evaluation in the prior art is solved.

The present invention relates to a detection circuit for an energy storage battery impedance spectrum and a control method thereof, and belongs to the field of battery detection technology. The circuit includes a floating detection circuit, a microprocessor control system, a programmable electronic load, a high-precision voltage sensor, a high-precision current sensor, a charge and discharge switch, a charging power supply, and a discharge load; before applying excitation, the circuit uses a balancing capacitor as a medium, and controls the charge and discharge switch so that the balancing capacitor voltage offsets the DC voltage of the energy storage battery, thereby improving the detection accuracy of small changes in the power battery terminal voltage; in the impedance spectrum detection stage, by controlling the current flowing through the programmable electronic load, the decoupling problem of the energy storage battery charge and discharge current and the excitation current is solved; by the frequency sweeping operation of the composite excitation signal, the rapid online detection of the internal impedance spectrum of the energy storage battery is realized. The present invention can accurately detect the dynamic and static internal impedance spectra of the energy storage battery, and provide data support for the health status assessment of the energy storage battery.

The objective of the present invention is to evaluate a battery with high accuracy using a simple method. A battery evaluation device (100) is provided with an impedance real part measuring unit for measuring the real part of the impedance of a battery, for each of a first frequency and a second frequency. The battery evaluation device (100) obtains an evaluation value indicating the state of the battery on the basis of the real part of the impedance of the battery obtained for each of the first frequency and the second frequency, a temperature coefficient and a capacity deterioration coefficient acquired in advance for the first frequency, and a temperature coefficient and a capacity deterioration coefficient acquired in advance for the second frequency. The evaluation value is at least one of a metal deposition amount and a temperature.

The invention relates to a positive electrode material, a positive electrode plate, a lithium ion battery and electric equipment, the positive electrode material comprises an active material and a carbon material layer coating the active material, and the positive electrode material satisfies 40 < WC * IG / Iv < 120. The positive electrode material disclosed by the invention has a good carbon coating effect, the conductivity of the material and the slurry processing performance can be enhanced, and when the positive electrode material is used in the lithium ion battery, the polarization of the battery can be reduced, the rate capability can be improved, the impedance of the battery can be reduced, and the battery has excellent rapid charging and discharging capability.

A battery state diagnosis apparatus includes a processor configured to extract battery impedance by obtaining voltage and current signals outputted from a battery management system of an electric vehicle, removing noise by performing first signal processing on the voltage and current signals outputted from the battery management system, and extracting a frequency characteristic by performing second signal processing on the voltage and current signals from which the noise has been removed, and a storage configured to store data and algorithms driven by the processor.

Disclosed are an internal temperature measurement method and apparatus for a battery, and an electronic device and a storage medium. The method comprises: acquiring a surface temperature of a battery, and determining a temperature interval in which the surface temperature is located; when the surface temperature is in a first temperature interval, selecting from an excitation frequency selection section an excitation frequency corresponding to the surface temperature, wherein the excitation frequency selection section includes a plurality of excitation frequencies; generating an excitation signal on the basis of the excitation frequency corresponding to the surface temperature, and outputting the excitation signal to the battery, so as to acquire a response signal fed back by the battery in response to the excitation signal; determining a battery impedance of the battery on the basis of the excitation signal and the response signal; and determining an internal temperature on the basis of the battery impedance.

A method for estimating battery impedance and remaining energy in a battery system, including a group of battery cells, includes periodically measuring current and voltages of all battery cells in the group of batter cells for a time period. The method also includes determining a present current value in accordance with averaging the measured current and voltages over the time period. The method further includes detecting a step change in a current based on a comparison of the present current value with one or more previously stored current vales. The method still further includes initiating an impedance measurement event in accordance with validating the step change.

According to the battery state monitoring method and system based on the battery impedance chip, battery internal resistance data are collected in real time through the battery impedance chip, and high precision and reliability of the data are ensured in combination with temperature compensation processing. The internal resistance data is deeply analyzed by using a support vector machine (SVM) model, so that the health state of the battery can be accurately evaluated, and the attenuation trend of the battery can be predicted. According to the method, the accuracy of battery health state evaluation is improved, and the safety of a battery system is enhanced through a real-time monitoring and early warning mechanism.