400 results about "Polarization voltage" patented technology

The invention relates to the technical field of lithium battery parameter determination methods, in particular to a lithium battery cycle life quick testing method. The method includes the steps of step 1, determining charge state interval for cycle life quick testing according to polarization voltage characteristics of a battery sample, step 2, carrying out a battery cycle life quick test to obtain cycle life test experimental data, step 3, carrying out cycle life mathematic model deduction in partial charge interval, step 4, establishing cycle life deduction mathematic models in 0-100% charge interval, step 5, obtaining a cycle life formula of a battery in the 0-100% charge interval, and step 6, estimating the cycle life of the tested battery. The lithium battery cycle life quick testing method overcomes the defects that time for conventional testing is long, and difference between an accelerated cycle life testing method and the reality is large, and shortens design, development and testing periods of batteries.

The present invention provides a tire pressure sensor system that has multiple functions and is integrated into a small package. The system includes one or more Micro Electro Mechanical System (MEMS)-based sensors, including a MEMS-based pressure sensor; a MEMS-oscillator-based wireless signal transmitter; and a microcontroller, where the microcontroller processes the data generated by at least one of the MEMS-based sensors, controls at least one of the MEMS-based sensors, and controls the encoding and timing of transmission of data from the wireless signal transmitter. Preferably, the MEMS-based sensors, MEMS-oscillator-based wireless signal transmitter, and microcontroller are integrated onto one or more chips in one or more packages. The system also preferably includes a MEMS-based motion sensor, a low frequency (LF) receiver, an IC-based voltage sensor, a voltage regulator, a temperature sensor and a polarization voltage generator. Thus, the disclosed tire pressure sensor system is high in functionality, yet small in size.

A time varying electrical excitation(s) is applied to a system containing biologic and/or non-biologic elements, whereupon the time-varying electrochemical or electrical response is detected and analyzed. For biologic specimens, the presence, activity, concentration or relative quantity, and certain inherent characteristics of certain target substances (hereinafter referred to as “target analytes”) within, or comprising, the specimen of interest may be determined by measuring either the current response induced by a voltage-mode excitation, or the voltage response induced by a current-mode excitation. Labeling or marker techniques may be employed, whereby electrochemically active auxiliary molecules are attached to the substance to be analyzed, in order to facilitate or enhance the electrochemical or electrical response. The method may also be employed to test non-biologic systems comprising an electrochemical cell or a battery of cells, wherein complex pulse type excitation signals are applied to the cell and the resultant time varying polarization voltage information is extracted and analyzed to determine at least one characteristic of the cell(s) condition or state.

The invention relates to the technical field of battery charging, in particular to a charging method of a lithium ion battery based on time and temperature. Polarization voltage limited maximum charging current is calculated based on lithium ion battery polarization characteristics, and under the constraint of the maximum charging current, charging temperature rise and charging time are considered comprehensively, genetic algorithm is employed to search the optimal charging current so as to balance the mutual contradictory objects of reducing charging time and lowering charging temperature rise. The result shows that the optimal charging current ensures charging rapidity, at the same time controls the polarization voltage and temperature rise of the charging process within an allowable range, and guarantees the charging capacity, charging efficiency and charging safety and battery life.

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.

An electrode arrangement for electrical stimulation of biological material has at least one stimulation electrode via which the biological material can be fed a stimulus signal. Furthermore, a counter electrode is present which forms a counter pole to the stimulation electrode, one sensor electrode is provided with the aid of which it is possible to determine a polarization voltage across the stimulation electrode.

An enhanced piezoelectric wire structure includes an elongated portion of piezoelectric material, a metallic core, and an outer conductive sheath. The metallic core is substantially surrounded by the elongated portion of piezoelectric material and configured to function as a first electrode for the piezoelectric structure. The conductive outer sheath preferably covers selected areas of the elongated portion of piezoelectric material and functions as a second electrode for the structure. The piezoelectric material may correspond to barium titanate ceramic fibers, such that a lead-free structure is effected, however other piezoelectric materials may also be utilized. The disclosed structure can be poled with a reduced poling voltage and lower temperature level, and also requires a reduced voltage potential level required for mechanical actuation. A collection of such piezoelectric structures can be provided together in a modular patch assembly that may be formed in a variety of customized configurations for integration with various environments, and can function as a mechanical actuator device, a condition-responsive device (e.g., a sensor) and/or as a power generation device. When utilized as a power generation device, the subject piezoelectric assembly can power tire electronics components such as a revolution counter, a sensor, a rechargeable battery, a flashing light assembly, a microcontroller, a global positioning system (GPS), and a radio frequency (RF) device.

The invention relates to a low-temperature rapid self-heating method for a lithium-ion battery. The method comprises the following steps: (S1) determining a polarization voltage amplitude range which does not have influence on the service lifetime of the lithium-ion battery and is safely used, and selecting a sine AC voltage amplitude according to the range; (S2) calculating the relationship between heat production power and frequency and obtaining a frequency point, namely the optimal heat production frequency point, with the maximum heat production power according to the relationship between battery impedance and frequency under the selected sine AC voltage amplitude; and (S3) carrying out heating free of lifetime loss on the battery by a sine AC signal according to the amplitude determined in the step (S1) and the frequency determined in the step (S2). The low-temperature rapid self-heating method for the lithium-ion battery has the effects of being high in heating rate, obvious in low-temperature performance improvement, free of an influence on the service lifetime of the lithium-ion battery, good in heating temperature uniformity and the like; and the target of reducing the influence on the service lifetime of the lithium-ion battery to the maximal extent is achieved.

There is a sort of reference source which has the crack by checking the high electrical source, and it consists of the self-polarization circuit, the regulating circuit, the kernel circuit which has the crack, and the startup circuit. The IPTAT generating circuit of the kernel circuit which has the crack makes the collector current of the Q1 and Q2 of the NPN pipe to equal by that the degenerative feedback which is magnified adjusts its quiescent point, the IPTAT current and the VBE of the Q8 of the NPN transistor which has the negative temperature coefficient in the constant-current circuit are progressed the first compensation of the temperature, at the same time they debase the temperature coefficient. The constant-current circuit produces the polarization by itself, and provides the polarization current to the IPTAT generating current. The operational amplifier circuit advances the plus for the two-stage operational amplifier, the compensation current progresses the frequency compensation for the two-stage operational amplifier. The generating circuit removes the dependency of the reference export VREF to supply voltage by negative feedback effect in order advance the PSRR. The startup circuit removes the degeneration polarization point and it drives the self-polarization circuit to work. The self-polarization circuit provides the polarization voltage for the regulating circuit. The circuit configuration of this invention is simple and new, it does not need the external polarization, the area of this circuit is small, and it has the good temperature coefficient.

The invention discloses a model inverse dynamic algorithm for the extreme power of a power battery pack, and aims to avoid the influence of the state of charge (SOC) accuracy of a battery on an extreme power estimated value due to calculation of the electrodynamic potential of the battery through a mathematical model. The model inverse dynamic algorithm comprises the following steps: establishing a polarization voltage model of a single battery and a terminal voltage model of the single battery by adopting a Thevenin equivalent circuit; computing the direct-current resistance R, polarization parameter Rp and tau of the battery according to an HPPC (Hybrid Pulse Power Characterization) experiment, and establishing a corresponding relation through the SOC and a temperature; computing current EMF(t) by using a current sampled voltage value U(t) and current I(t); computing a polarization voltage Up(t+dt) after pulse time according to Up(t); calculating extreme current according to EMF(t) and Up(t+dt); comparing the extreme current with a system design required value Imax, and selecting lower current for calculating a voltage value U(t+dt) after the pulse time; and computing extreme power and charging extreme power.

The invention discloses an SOC estimation method based on an adaptive double extended Kalman filtering method. The SOC estimation method comprises the following steps: firstly, establishing a second-order RC equivalent circuit model of a lithium battery; then, determining open-circuit voltage and battery equivalent model parameters at different SOC (state of charge) positions of the lithium battery through a pulse charging and discharging experiment; obtaining a function relationship between the open-circuit voltage and the SOC and relationships between other model parameters and different SOCs, the other model parameters including ohmic internal resistance, electrochemical polarization resistance, electrochemical polarization capacitance, concentration difference polarization resistance and concentration difference polarization capacitance values; establishing a state space equation taking the SOC and polarization voltage as state variables and a state space equation taking the ohmicinternal resistance as a state variable; and finally, performing iterative computation to obtain the SOC value of the lithium battery in real time. According to the method, the problem of unknown noise statistical characteristics in the prior art is solved, and meanwhile, the ohmic internal resistance of the battery is estimated by using the Kalman filtering algorithm, so that the model precisionis improved.

The invention discloses a method for realizing online prediction of maximum permissible power of a lithium ion battery. The method comprises the steps of: establishing a battery physical model according to charging and discharging characteristics of the lithium ion battery, and calculating a state of charge and a polarization voltage of the battery; utilizing the battery physical model to calculate a difference value between a battery terminal voltage and a battery charge and discharge limiting voltage by taking the state of charge and the polarization voltage as initial conditions and takingbattery-permissible maximum transient charging and discharging current as an initial probe current; and acquiring an increment for adjusting the probe current according to the difference value betweenthe battery terminal voltage and the battery charge and discharge limiting voltage so as to obtain a new probe current, and calculating a terminal voltage of the battery circularly by means of the battery physical model until a condition of calculating maximum permissible charge and discharge power in a current operating state is satisfied, thereby realizing online real-time prediction of a maximum power state of the lithium ion battery. The method overcomes the difficulty that the maximum permissible charge and discharge power estimation is subject to coupling constraints of working conditions, temperature, state of charge, attenuation and the like, and guarantees the estimation precision.

The invention discloses a wear-type electrocardioelectrode device and a manufacturing method thereof. The wear-type electrocardioelectrode device comprises a dress which is equipped with at least six electrodes, the electrodes on the dress are connected with an external device by leads, and the electrodes are made from silver fiber by spinning. The wear-type electrocardioelectrode device can ensure good and reliable contact of the electrodes with human body, reduce contact resistance between human skin and the electrodes, reduce production of polarization voltage, enhance signal reliability, and is comfortable and easy to wear, safe, convenient for use, and can realize long-term monitoring on cardioelectricity, heart rate, breath and body temperature.

There is provided an apparatus that calculates a polarization voltage of a secondary battery. A temperature sensor detects a temperature of the secondary batter; a voltage sensor detects a voltage of the secondary battery; and a current sensor detect an electric current of the secondary battery. A battery ECU calculates a polarization voltage based on the electric current and adaptively sets an upper limit value and a lower limit value of the polarization voltage according to a temperature characteristic of the secondary battery. The calculated polarization voltage is compared with an upper limit value and a lower limit value, whereby the polarization voltage is corrected. An SOC is estimated based on the corrected polarization voltage.

There is provided a battery pack system with enhanced estimation accuracies of a polarization voltage and a remaining capacity of a secondary battery. A polarization voltage calculation section 108 calculates a polarization voltage Vpol from a filtered variation LPF (ΔQ) of an accumulated capacity with reference to a look-up table (LUT) 1081. An electromotive force calculation section 113 subtracts the polarization voltage Vpol from an effective no-load voltage V0_OK to determine a battery electromotive force Veq. A remaining capacity estimation section 114 estimates a remaining capacity SOC from the battery electromotive force Veq with reference to a look-up table (LUT) 1141.

Disclosed is an apparatus and method for estimating a parameter of a secondary battery. The apparatus according to the present disclosure includes a sensor means configured to measure a plurality of current-voltage data while a charging current decreases when a secondary battery is charged in such a pattern that the charging current increases to a peak value and then decreases, and a control means configured to receive an input of the plurality of current-voltage data from the sensor means, calculate a linear approximation equation representing a correlation between a current and a voltage from the plurality of current-voltage data, estimate an open-circuit voltage (OCV) of the secondary battery by reflecting a polarization voltage of the secondary battery quantified through a resistor-capacitor (RC) circuit on a Y intercept of the linear approximation equation, and estimate a state of charge (SOC) of the secondary battery from the estimated OCV.

The invention discloses a method for dynamically evaluating battery consistency. The method comprises steps of (1) carrying out series connection of two batteries to be measured to form a battery group to be measured, (2) carrying out the series connection of the battery group to be measured and a load to form a loop, (3) carrying out constant current discharging or charging on the battery group to be measured and collecting the voltage and discharging capacity or charging capacity of the batteries, (4) changing the load which is in series connection in the step (2), (5) carrying out constant current discharging or charging on the battery group to be measured and collecting the remaining capacity of each battery to be measured and the polarization voltage of the battery, (6) calculating the dynamic DC resistance of each battery to be measured according to the collected data, (7) calculating the consistency coefficient of each battery to be measured according to the above data, and (8) judging the consistency of the batteries to be measured according to the consistency coefficient of each battery to be measured. Through measuring and comparing the data of the batteries in parallel connection in a dynamic environment, the essential difference of a battery group can be directly identified, the group performance of the batteries can be improved, the consistency of the batteries is improved, and the service life of the battery group is prolonged.

A battery energy storage system state assessment method comprises steps of obtaining operation data of a to-be-assessed battery energy storage system, and performing calculation to obtain real-time radiation conditions of charging state consistency of the to-be-assessed battery energy storage system according to the operation data; obtaining test working condition data of the to-be-assessed battery energy storage system according to a preset period, performing calculation to obtain residual capacity, peak power, polarization voltage, open-circuit voltage, temperature rise performance and charging state estimation condition of the to-be-assessed battery energy storage system according to the test working condition data, and obtaining the decline condition of the to-be-assessed battery energy storage system according to the residual capacity, the peak power, the polarization voltage, the open-circuit voltage, the temperature rise performance and the charging state estimation condition; and obtaining an assessment result of the to-be-assessed battery energy storage system according to the real-time radiation conditions of charging state consistency of the to-be-assessed battery energy storage system and the decline condition of the to-be-assessed battery energy storage system.

The invention provides a method for calculating the maximum charging current of a power lithium ion battery, which belongs to the technical field of lithium ion batteries, wherein based on polarization and temperature rise characteristics of the lithium ion battery, a model about a charging polarization voltage and a charging temperature rise of the lithium ion battery is established, limits for the polarization voltage and the charging temperature rise are set during charging, the method for calculating the maximum charging current of the power lithium ion battery based on the polarization voltage limit and the temperature rise limit is put forward, a charging current curve which changes with an SOC in a stepped manner is put forward according to a curve of the proposed maximum charging current based on the temperature rise limit and the polarization voltage limit, the quick charging is ensured, the polarization voltage and the temperature rise are limited in an allowable scope during the charging, charging capacity, charging efficiency and charging safety are ensured, and service life of the battery is prolonged.