253 results about "Ampere-hour" patented technology

A method for determining the battery state of charge SOC adopts corrected ampere hour integration method (Figure) to determine the battery state of charge SOC value at the time of t; the measurement method of the correction function fai (t) comprises the following steps: an SOC theoretical value calculated formula is adopted to calculate the battery state of charge SOC theoretical values SOC(theoretical) at a plurality of times; and the battery state of charge SOC actual values SOC(actual) at the plurality of times are measured; through the least square method, the correction function fai (t) standing for the relation between the difference value between the SOC(theoretical) and the SOC(actual), and the plurality of times; wherein, the SOC theoretical value calculation formula in step (a) adopts the basic ampere hour integration method (see the above formula); and x stands for one of the plurality of times. The application of the method can obtain accurate correction functions so as to achieve more precise battery state of charge SOC values to give full play to the battery performance and ensure the safety of the complete vehicle systems.

The invention discloses a battery charge state detection method. The method is characterized by normalizing voltage-charge state curves with different temperatures and different cycle charging and discharging times which are stored in a memory chip to obtain a battery charge state value SOC of a battery charging and discharging normalization curve for calibration based on an ampere-hour measurement method. The method has little error, and is applicable to static state of the battery as well as working state of the battery, In addition, correlation curves can be established by a logistic fitting tool, which simplifies the modeling process and facilitates application of the method.

The invention discloses a self-correction method for remaining capacity estimation of a lithium iron phosphate power battery. The conventional method cannot meet national standard well. According to the self-correction method disclosed by the invention, compensation and correction are performed on the basis of estimating the remaining capacity of the lithium iron phosphate power battery by using an ampere-hour method; and according to the characteristic that voltage of the lithium iron phosphate power battery abruptly changes at the end stage of charging or discharging, the actual remaining capacity SOC (State Of Charge) is corrected when dV / dSOC' is detected to be greater than or equal to 0.05, so that accumulative estimation error existing during independent use of the ampere-hour method is reduced. The self-correction method is based on the ampere-hour method, is simple and easy and is easier to apply and generalize. Meanwhile, the invention also provides a calculation method of aging rate gamma. By continuously updating the aging rate, the error for estimation by using the ampere-hour method is reduced again.

The invention discloses a method for estimating an SOC of a lithium battery. The method comprises the following steps of (S1) obtaining an SOH value of the battery, and determining the current maximum available capacity CN of the battery; (S2) calculating a current SOC value of the battery online by using an ampere-hour integral method; (S3) starting a corresponding offline model parameter according to a sampling temperature T and an estimated value of the current SOC of the battery, and calculating current open-circuit voltage OCV by combining the current sampling current I and terminal voltage U; (S4) obtaining a real value SOC (t)* of the current SOC of the battery according to the estimated value of the current SOC of the battery in the step (S2), the current open-circuit voltage OCV in the step (S3) and an OCV-SOC calibration curve; (S5) correcting the current estimated SOC value of the ampere-hour integral method by using the real value SOC (t)* of the current SOC of the battery, and further carrying out calculation by using the ampere-hour integral method; and (S6) repeating the steps (S3), (S4) and (S5). According to the method, piecewise correction is carried out on a traditional algorithm for estimating the SOC by the ampere-hour integral method, an accumulative error of the ampere-hour integral method is effectively eliminated, and the estimation accuracy of the SOC is improved.

The invention discloses an SOC (state of charge) online estimation method for a lithium ion battery. The SOC online estimation method comprises the following steps: recognizing characteristic parameter values of the battery online; recognizing real-time SOC of the battery online; revising the battery SOC through ampere-hour integral estimation to obtain revised SOC; and weighing the real-time SOC and the revised SOC to obtain final SOC of the battery. By the SOC online estimation method, online estimation capability of battery characteristic parameters can be improved; evaluation self-adaptive capability of the SOC is stronger, and reliability is higher.

The invention provides an estimation method of the initial state of charge (SOC0) of a lead-acid cell. The method includes the following steps: a. collecting current flowing through the cell and end voltage of the cell; b. judging whether the cell is in the standing state, entering step c on not judgment and entering step d on yes judgment; c. adopting the relation between the SOC0 and the end voltage and the discharge multiplying power under the discharge state to obtain the initial SOC and entering step g; d. judging whether the cell is in the stable state, entering step e on no judgment and entering step f on yes judgment; e. utilizing the SOC value recorded before standing as the initial SOC and entering the step g; f. adopting the OCV-SOC relation in the standing state to obtain the SOC and entering the step g; g. adopting an ampere-hour integral method to estimate the SOC of the cell in real time. The estimation method considers the discharge state and the standing state of the cell and effects of the discharge multiplying power, standing time and the like on the SOC0, and improves estimation accuracy of the SOC0 accordingly.

The invention discloses an estimating method for the initial value of the stage of charge of a high-accuracy lithium ion battery and belongs to the technical field of automobile power batteries. The estimating method comprises the following steps: firstly, according to a corresponding relation curve of the open-circuit voltage and an SOC (Stage of Charge) at different temperatures, estimating an open-circuit voltage stage of charge (SOCocv) through the lookup table; secondly, according to standing time of the battery, the current voltage platform of the battery and the battery pack temperature, obtaining a power-on initial stage of charge through the three-dimensional lookup table; finally, according to the self-discharging characteristic of the battery, correcting the initial stage of charge. Through the adoption of the method disclosed by the invention, an accumulated error caused by inaccuracy of the initial value estimated through an ampere-hour integral method and the estimation error of stage of charge caused by static current loss in the shutdown process are effectively reduced on the basis of factors of the characteristics of the open-circuit voltage at different temperatures, the standing time of the battery, the self-discharging characteristics of the battery and the like, and the higher accuracy is achieved. The method is suitable for SOC initial value estimation of a single battery, a module and a battery assembly.

The invention relates to an estimation and implement method of state of charge (SOC) of battery for electric car, belonging to the field of electric car intelligent niformation processing technology. Said method utilizes the state space equation of battery which is formed from battery charge state equation based on ampere-hour metering method and measurement equation of battery load votlage, and uses the improved extended Kalman filtering equation to calculate and obtain the stale of charge of battery. Said invented advantage lies in that it has stronger adaptability, can eliminate initial error of SOC, and can raise the convergence of error or reduce speed, at the same time it can modify the change of SOC resulted frmo self-discharge of battery. Said invention is applicable to SOC estimation of cell monomer, module and battery.

The invention discloses a lithium battery SOC estimation method of off-line data segmentation correction. The method is mainly applied to a battery management system of an electric vehicle and is used for correcting an actual capacity of a lithium battery and eliminating an accumulation error of a traditional ampere-hour integral method. The method comprises the following steps of establishing a battery equivalence circuit model; acquiring an OCV-SOC curve; using a terminal voltage response curve at the time that battery discharging is ended to carry out off-line parameter identification on the equivalence circuit model; calculating a battery health state SOH; using an ampere-hour integral method to calculate a current value of the SOC in real time; using the battery health state to correct a SOC value; using off-line data to carry out segmentation elimination on the accumulation error in the ampere-hour integral method. By using the method of the invention, the battery SOC can be accurately estimated and the accumulation error of battery SOC estimation performed through using the ampere-hour integral method is eliminated.

The invention discloses a method and system for estimating SOC (State-of-Charge) of a power battery based on dynamic parameters. The method comprises the following steps: carrying out a discharge-standing experiment on the battery, obtaining OCV (Open Circuit Voltage)-SOC characteristic curves of the battery at different temperatures, and fitting out an OCV-SOC relational expression; carrying out a constant current pulse discharge-standing experiment on the battery, recording voltage response during the experiment, and identifying the initial value of the parameter of a battery second-order RC equivalent circuit model by an offline method; carrying out dynamic parameter identification on the second-order RC equivalent circuit model by using a forgetting factor-containing recursive least squares method RRFLS; carrying out online estimation on the SOC of the battery by using an EKF (Extended Kalman Filter) algorithm. The estimation method overcomes the defects of inaccuracy and cumulative error of the initial value of SOC in an ampere-hour integral method, and adapts to the dynamic change of battery characteristics, the battery model is high in precision and convergence speed, and is stable and reliable, and the precision of SOC online estimation is improved. The method and system can be widely used in fields of electric vehicles and energy storage battery management systems.

The present invention discloses an SOC (state of charge) estimation method. According to the method, a battery OCV-SOC relationship module, a parameter acquisition module, an offline identification parameter value, a parameter discrete state space model, a battery parameter online identification module, a battery dynamic parameter update module and a battery SOC estimation module. The method includes the following specific steps that: 1, a discharge-standing experiment is performed, an OCV-SOC relationship expression is obtained through fitting, parameter values in an equivalent circuit model are identified; 2, a battery second-order RC system discrete state space model is established, and the battery model parameters are identified online and dynamically updated; and 3, the SOC of a battery is estimated online. With the method of the invention adopted, the defects of inaccuracy and accumulative error of the initial value of the SOC of a battery of in an ampere-hour integration method can be eliminated. The method is applicable to the dynamic change of the characteristics of the battery, can improve the accuracy of SOC online estimation and can be widely applied to the electric vehicles and storage battery management system field. The method has the advantages of high battery model precision, fast convergence, high stability and high reliability.

The invention relates to an estimating method of the charge state of a power battery. The estimating method is characterized by including the following steps: estimating system on chip (SOC) initial value of the battery according to last charge-discharge state of the battery and SOC value and standing time of the battery since last-time use comprehensively, calculating battery inner resistance and polarization voltage of the battery, collecting working current and voltage at two ends of the battery in real time, estimating SOC of the battery according to the SOC comprehensive estimation algorithm based on an expansion Kalman filtering method and an ampere-hour metering method, storing the SOC of the battery and the corresponding working current and voltage at two ends of the battery, storing current time, battery SOC and battery charge-discharge state before the system is closed down and closing the system down. The estimating method has the advantages of being small in SOC initial value, simple in algorithm, small in metering quantity and high in accuracy.

The invention discloses a battery capacity correction method based on an improved ampere-hour integral method. The method comprises the following steps: enabling a battery pack to run in a vehicle-mounted way; calculating the state of charge (SOC) by the ampere-hour integral method; judging whether the electric quantity of batteries is too low or not; judging whether the minimum battery voltage V<min> is lower than the threshold voltage V<mdy> in a capacity correction mode or not; entering the capacity correction mode; carrying out capacity correction, and then quitting the capacity correction mode; charging the batteries, and calculating the SOC; judging whether the maximum voltage V<max> of the battery pack is higher than charge cut-off voltage V<h> or not; finishing charging, storing the battery capacity Q accumulated in the charging process, and replacing the previous battery capacity Q<n> by the battery capacity Q; modifying the current battery capacity value to be Q, and modifying the value of the SOC. According to the method, the SOC values of the batteries and the stored electric quantity values are corrected at the end of the battery charging process, so that the accurate initial value of the SOC can be obtained after every time of charging is finished; furthermore, at the end of discharge, the batteries can select to enter the battery capacity correction mode, so that the current capacities of the batteries can be corrected, and thus the calculation error caused by battery aging can be eliminated.

The invention discloses a battery charge state detecting method. The method comprises the steps that the initial SOC of a battery is determined; the self-discharge effect of the battery is considered; a table look-up method is used to accurately estimate the SOC of the battery; an ampere-hour integral method is used to acquire the SOC estimation value of the battery of a next moment; a battery Thevenin model is combined, and an extended Kalman filter algorithm is used to correct the SOC of the battery; and finally, low power, over-current, over-temperature and the like of the battery are judged to carry out early warning and protection. According to the method provided by the invention, the influence of self-discharge of the battery on the battery capacity and the influence of temperature, the number of times of cycle charge and discharge and charge and discharge current on the rated capacity of battery are comprehensively considered, wherein self-discharge of the battery is caused by first time of running and downtime of the battery; error correcting is carried out on the SOC of the battery; and the accuracy is improved.

The invention provides a method for accurately estimating an SOC (State of Charge). The charge curves of a battery at different temperatures and different multiplying powers are utilized, the SOC is corrected according to monomer voltage when the battery is charged, and the estimate accuracy of the SOC is improved. The method comprises the two steps of low end correction and high end correction. The method provided by the invention has the advantages that the correcting opportunity of the SOC is increased, the estimate accuracy of the SOC is increased, and the method is simple and easy to realize, popularize and use. According to the invention, the low ends and the high ends of the charge curves are fully utilized to correct the SOC on the basis of an open-circuit voltage process and an ampere-hour integration process. As the low-end correction of the SOC is increased in the charge process, the estimate accuracy of the SOC under charge interruption conditions can be improved.

The invention relates to a method and device for estimating a charge state of a lithium ion battery. The method comprises the following steps: A, fitting a relation between the open-circuit voltage and the charge state of the lithium ion battery; B, estimating the charge state of the lithium ion battery by utilizing an observer method; C, if the charge state of the lithium ion battery estimated in the step B is larger than a predetermined threshold value, estimating the charge state of the lithium ion battery by using the observer method, and if the charge state of the lithium ion battery estimated in the step B is smaller than the predetermined threshold value, estimating the charge state of the lithium ion battery by using an ampere-hour integral method. Through the method and the device for estimating the charge state of the lithium ion battery, provided by the method, the defects of the ampere-hour integral method and the observer method can be overcome, and the high estimation accuracy is provided in a full life cycle and a full charge state region.

The invention relates to the technical field of power batteries of electric automobiles, and discloses a composite estimating method of a power battery SOC based on a PNGV equivalent circuit model. The composite estimating method comprises the following steps that A, the open-circuit voltage of the power battery is detected; B, an open-circuit voltage method is used for calculating the primary SOC (t0) of the power battery; C, in the time period of t0-t1, an EKF algorithm is used for correcting the primary SOC (t0), and an SOC (t1) is obtained; D, in the time period of t1-t2, an improved ampere-hour integral method is used for estimating; E, when the power battery is continuously used, the steps from the step C to the step D are circulated; the t0 represents the primary time, and the t1 and t2 represent the time points after the t0. According to the composite estimating method of the power battery SOC based on the PNGV equivalent circuit model, the correction coefficients of influencing factors such as the charging and discharging currents of the power battery, the environment temperatures, the battery health state are considered, the improved ampere-hour internal method is used, and the defect that the influence from outside factors is large when the ampere-hour internal method is used for estimating the power battery SOC can be overcome. The advantage that an EKF method has a powerful correcting effect on initial errors of the SOC is fully used.

The invention discloses methods for predicting the SOC of a vehicle-mounted power battery of an electric automobile. The methods for predicting the SOC of the vehicle-mounted power battery of the electric automobile comprises the method for predicting the SOC in the charging mode, and the method for predicting the SOC in the discharging mode. The methods for predicting the SOC of the vehicle-mounted power battery of the electric automobile are based on an existing open-circuit voltage method and an existing ampere-hour integral method, an optimal battery model is obtained through curve fitting of the temperature, the voltage, the charging current and the discharging current of the battery, branch processing is conducted on the charging state and discharging state when an SOC value is estimated in real time, a corresponding SOC value is searched for in a model library by means of the immobilized battery model according to the temperature characteristic, the voltage characteristic and the current characteristic, of the battery, the SOC value is modified according to model errors, and the estimation accuracy is greatly improved.

The invention discloses a battery SOC (state of charge) correction method, comprising: matching, by a battery management system, acquired battery voltage, current and temperature values with preset OCV (open circuit voltage) curve table and EDV (end of discharge voltage) curve table to find out OCV state theoretical SOC value SOC<o> and EDV theoretical SOC value SOC<e>, and acquiring DeltaSOC<o> and DeltaSOC<e> according to current SOC value SOCP; comparing DeltaSOC<o> and DeltaSOC<e>, executing DeltaSOC<o> or DeltaSOC<e> to correct the SOC value in conjunction with standing time for triggering DeltaSOC<o> correction settings and voltage value for triggering DeltaSOC<e> correction settings, and determining a correction coefficient; using the correction coefficient as ampere-hour integral to calculate a variable factor of a battery real-time SOC variable, and smoothing a discharge curve so that SOC is gradually close to true value. The SOC correction method of the invention can estimate battery SOC more accurately.

The present invention provides a method for estimating and correcting lithium manganate series battery pack SOC value. The SOC calculation method of a single cell and a battery pack is redefined, four different suitable opportunities are selected, different algorithms are used, a single battery remaining capacity affected by an ampere-hour integral accumulation error and a single battery maximum available capacity affected by temperature change and aging are corrected respectively, thus the maximum available capacity and the remaining capacity of a battery pack are corrected, and the correction of an SOC single value at a particular time point is realized. In addition, for a battery pack SOC real-time calculation formula, the invention provides a more accurate initial value and a battery pack maximum available capacity value, and thus the battery pack SOC calculated in an online way is more accurate.

The invention relates to a calibration and estimation method for a state of charge (SOC) of a lithium battery based on a charge mode. An error source of an Ampere-hour integral method is analyzed, an SOC initial value is calibrated by using an open-circuit voltage (OCV) of the lithium battery in a static state, the total capacity is calibrated by using the SOC values estimated through the OCV in the static state before and after charging, a mapping relationship between terminal voltages and the SOC values is established, and high-precision estimation of the SOC value of the lithium battery system within a discharge cycle is realized by using battery characteristics of different charge phases of constant current and constant voltage.

The invention discloses a method and system for evaluating the health state of a battery. The method comprises: S1, acquiring life decay data of a plurality of batteries of the same type; S2, according to the life decay data, constructing target characteristic parameters of the batteries and calculating a capacity data sequence; and S3, on the basis of a least square method, fitting of the capacity data sequence and the target characteristic parameters is carried out to construct a health state assessment model for calculating effective capacities of the batteries. The target characteristic parameters include at least one of the following parameters: an equal-voltage-drop discharging ampere-hour value, an equal-ampere-hour discharging voltage difference, an equal-voltage-drop charging ampere-hour value, and an equal-ampere-hour charging voltage difference. According to the invention, no complicated testing condition or model as well as no complete charging and discharging voltage curves on the constant current condition of the battery is needed; and the health state of the battery can be predicted accurately.

The present invention relates to a battery SOH estimation method of an energy storage power station BMS. The method comprises the following steps: the step S1: electric operation on a system; the step S2: circle and timing collection of battery real time data and extraction of a single voltage, a single internal resistance, a battery temperature, a charge-discharge current and a charge-discharge electric quantity from the real time data; the step S3: respective estimation of a battery SOH through an open-circuit voltage method, an ampere-hour integral method, a Kalman filtering method and a resistance method via the combination of nominal parameter of the battery and collected real time data of the battery; and the step S4: comprehensive calculation of the battery SOH obtained by estimation through a historical data amendment method to work out a model for calculating SOH coefficients, wherein the model for calculating SOH coefficients may be used in subsequent each SOH analytical calculation. The estimation method described herein is strong adaptable to storage batteries under various environments, and has a self-calibration function and high estimation accuracy, wherein the estimated value is approximate to the real value, thereby the real health status of the battery may be relatively accurately reflected.

The invention discloses a power battery water-cooling unit system and an intelligent temperature difference control method thereof. The power battery water-cooling unit system comprises a water cooling unit and a water cooling unit controller, wherein the water cooling unit comprises a compressor, a pressure switch, a condenser, a condensation fan, a liquid storing and drying tank, an expansion valve, a plate type exchanger, a PTC heater, a three-way valve, an inlet water temperature sensor, a power battery box, an outlet water temperature sensor, a water tank and an electronic water pump, wherein the compressor, the pressure switch, the condenser, the condensation fan, the liquid storing and drying tank, the expansion valve and the plate type exchanger are connected with each other in series. Through the power battery water-cooling unit system, the automation degree of the control of the power battery water-cooling unit is improved; the control system is capable of judging the difference between the battery average temperature and the outlet water temperature of the water cooling unit, adaptively adjusting operation rotation rate of the compressor, the electronic water pump and the condensation fan in real time through an intelligent control algorithm, indirectly controlling a battery to operate in the optimal temperature range and the optimal temperature difference range and predicting the battery temperature trend in advance through ampere-hour integral.

The invention discloses a modeling method of a liquid state or semi-liquid state metal battery. The modeling method comprises the following steps: according to a battery impedance spectrum, carrying out fitting, constructing a battery impedance spectrum fitting circuit, and constructing the equivalent circuit model of the battery according to the battery impedance spectrum fitting circuit; adopting symmetrical impulse to carry out a hybrid impulse power performance test on the battery, and obtaining test data used for distinguishing the open-circuit voltage, the resistance and the capacitance parameters of the battery; according to the test data, fitting a function relationship between SOC (State of Charge) and the electrodynamic force, the Ohmic internal resistance, the polarization resistance, the polarization capacitance, the diffusion equivalent resistance and the diffusion equivalent capacitance of the battery, and distinguishing the parameters of the equivalent circuit model; adopting an ampere-hour method to calculate the SOC of the battery; correcting the SOC to obtain a corrected SOC; according to the corrected SOC, correcting the parameters of the equivalent circuit model; and finishing modeling. The modeling method can accurately simulate the external characteristics of the liquid state or semi-liquid state metal battery, and lays a foundation for the charging and discharging management and the subsequent application of the type of novel power grid type energy storage battery including the liquid state or semi-liquid state metal battery.

Electrochemical energy storage devices, such as alkali metal-oxygen battery cells (e.g., non-aqueous lithium-air cells), have a cathode architecture with a porous structure and pore composition that is tailored to improve cell performance, especially as it pertains to one or more of the discharge / charge rate, cycle life, and delivered ampere-hour capacity. A porous cathode architecture having a pore volume that is derived from pores of varying radii wherein the pore size distribution is tailored as a function of the architecture thickness is one way to achieve one or more of the aforementioned cell performance improvements.

The invention provides an online estimation method of a power lead-acid battery of a special engineering vehicle. The method comprises the following steps: 1, calculating an initial residual capacity SOC0 and an effective rated capacity Qt of a battery when a battery management system is powered on; 2, during charge and discharge process of the battery, using a corrected ampere-hour integration method to calculate the residual capacity of the battery; 3, using an internal resistance method based on a battery model to correct the residual capacity; and 4, outputting an online estimation result. The method utilizes a simple and practical SOC estimation model, integrates various factors, which affect the residual capacity of the storage battery, into the battery model, improves the estimation precision of the residual capacity of the battery, and has great practical meaning.

The invention provides an evaluation method of SOC of a power lithium ion battery management system. The method includes: firstly, simulating the battery by employing a first-order RC equivalent circuit model according to internal electrical characteristics of a lithium ion power battery; determining a polarized internal resistance R1, a polarized capacitance C1 and an ohmic internal resistance R0 etc. of the power battery as key parameters; performing preliminary identification on model parameters with the combination of a charge and discharge experiment; and on the basis, with the combination of a conventional SOC evaluation method, aiming at the lithium ion power battery, establishing an SOC estimation strategy based on Kalman filtering and with the combination of open-circuit voltage correction and an ampere-hour integration method. The test shows that the SOC estimation precision can reach less than 3%.