252 results about "Cell impedance" patented technology

The invention relates to the battery impedance spectroscopy testing technology. The invention provides a battery impedance spectroscopy testing method, which imposes the current incentive I(t) on the battery, and through synchronous measurement of current incentive I(t) and terminal voltage response U(t), calculates the amplitude spectrum I(Omegak), U(Omegak) and phase spectrum phiI(Omegak), phiU(Omegak) of current incentive I(t) and terminal voltage response U(t) under a variety of frequencies, and according to the spectrum of I and U, calculates the battery inner impedance Z0(Omegak)=U(Omegak) / I(Omegak) under a variety of frequencies, resulting in the complete spectra of battery inner impedance. The invention also provides a battery impedance spectroscopy testing system, including the control and data processing module, the high-speed synchronous sampling and measurement module, the voltage and current signal isolation and modulating module, the discharge control module, the controllable discharge module. Using the method and system in this invention, it can quickly complete the battery impedance spectrum measurement and analysis in a short time, greatly increasing the measurement efficiency.

A solid-state lithium battery including a lithium-containing anode and a phosphorus-containing cathode is disclosed. The cathode may include any of a number of electronically conductive allotropes of phosphorus, referred to as a group as black phosphorus. A solid discharge product of the cell acts as an electrolyte for the cell. The cathode may include an auxiliary electronic conductor phase to improve the conductivity of the cathode, improve the cathode utilization during discharge and reduce the overall cell impedance.

A method for determining the state of health (SOH) of a battery is provided in which cell impedance is determined continuously, and including determining one or more confidence coefficients that depend on one or several variables selected from cell current, temperature or state of charge or their derivatives or integrals with respect to time, and continuously determining the state of health of the battery at a given point in time, using the state of health of the battery at a preceding point in time corrected as a function of cell impedance determined at the given point in time and weighted by the confidence coefficient or coefficients. The method provides a reliable way of determining the state of health of the battery with greater stability and robustness than existing methods.

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.

A battery operable electrical device, such as a mobile telephone or a laptop computer, with a clock frequency generator operable to generate electrical clock frequency signals, and a first electrical circuit adapted to perform a first or main function of the device, utilizing the clock frequency signals generated by the clock generator. The device further includes a second electrical or auxiliary circuit adapted to generate an electrical excitation signal with an excitation frequency derived from the clock frequency signals. The excitation signal is fed to battery terminals of the device, and the second electrical circuit receives, from a battery connected to the battery terminals, an electrical signal in response to the excitation signal, and to analyze the received signal for the battery impedance at the excitation frequency and, based on the battery impedance, the state-of-charge of the battery is estimated.

A method and system for determining the temperature of cells in a battery pack, without using temperature sensors, by measuring the impedance of the cells and using the impedance to determine the temperature. An AC voltage signal is applied to the battery pack, and a time sample of voltage and current data is obtained. The voltage and current data is narrowed down to a simultaneous time window of interest, and a fast fourier transformation is performed on the windowed voltage and current data to identify voltage and current magnitudes at one or more specific frequencies. The voltage and current magnitudes are used to determine the impedance at the one or more frequencies. Finally, the impedance is used to determine the temperature of the cell or cells using a look-up table, where the impedance, the frequency, and a state of charge are used as input parameters for the look-up.

Battery impedance testing devices, circuits, systems, and related methods are disclosed. An impedance measurement device includes a current driver configured to generate an excitation current signal to be applied to a test battery responsive to a control signal, and a processor operably coupled with the current driver. The processor is configured to generate the control signal during an auto-ranging mode and a measuring mode. The auto-ranging mode applies the excitation current signal to the test battery over a plurality of different amplitudes to measure a response to the excitation current signal at each amplitude. The measuring mode applies the excitation current signal to the test battery for an amplitude responsive to the results of the auto-ranging mode. Improved sensitivity and resolution may be achieved for low impedance batteries with a rapid measurement time.

The invention discloses an on-line secondary battery simplified impedance spectroscopy model parameter estimating method based on fractional order united Kalman filtering, relates to an on-line estimation method of battery parameters, and aims to improve the accuracy, the estimation speed and the working condition adaptability of secondary battery parameter estimation. The method is based on a simplified battery impedance spectroscopy equivalent circuit model, a state equation and an observation equation required by an algorithm are established, the diffusion polarization end voltage (UW), the open-circuit voltage (OCVe), the internal ohm resistance (Ro) and the diffusion parameter (XW) of a battery are taken as the estimators by using a fractional order united Kalman filter, the end voltage (UL), the load current (IL) and the sampling time interval Ts being 1s which are measured in real time are taken as known amount, noise covariance is excited and measured according to the sensor precision selection process, and the estimation values of the open-circuit voltage (OCVe), the internal ohm resistance (Ro) and the diffusion parameter (XW) of a battery model are obtained. The on-line secondary battery simplified impedance spectroscopy model parameter estimating method is applicable to on-line estimation of secondary battery parameters.

A method for determining the state of health (SOH) of a battery is provided in which cell impedance is determined continuously, and including determining one or more confidence coefficients that depend on one or several variables selected from cell current, temperature or state of charge or their derivatives or integrals with respect to time, and continuously determining the state of health of the battery at a given point in time, using the state of health of the battery at a preceding point in time corrected as a function of cell impedance determined at the given point in time and weighted by the confidence coefficient or coefficients. The method provides a reliable way of determining the state of health of the battery with greater stability and robustness than existing methods.

The invention discloses a method for detecting consistency of single batteries. The method comprises the steps that the qualified single batteries are discharged, the actual battery capacity of the single batteries is detected, and the single batteries are graded according to the capacity difference standard; ohmic resistance testing and polarization resistance testing in high-temperature and low-temperature work areas are carried out on the single batteries of the same grade, and the single batteries are graded according to the difference standard of the tested battery resistance values; a battery unit is formed by selecting the single batteries of the same grade. The work characteristics of lithium ion batteries in the high-temperature area and the low-temperature area are considered comprehensively, the consistency of the batteries can be distinguished more directly, and therefore damage caused by inconsistency of the batteries to the battery set is reduced, and the service life of the battery set is prolonged.

Electrolytes for use in commercially viable, rechargeable lithium metal batteries are described. The electrolytes contain one or more lithium salts, one or more organic solvents, and one or more additives. The electrolytes allow for reversible deposition and dissolution of lithium metal. Specific additives or additive combinations dramatically improved cycle life, decrease cell swelling, and / or lower cell impedance.

Energy storage cell impedance testing devices, circuits, and related methods are disclosed. An energy storage cell impedance measuring device includes a sum of sinusoids (SOS) current excitation circuit including differential current sources configured to isolate a ground terminal of the differential current sources from a positive terminal and a negative terminal of an energy storage cell. A method includes applying an SOS signal comprising a sum of sinusoidal current signals to the energy storage cell with the SOS current excitation circuit, each of the sinusoidal current signals oscillating at a different one of a plurality of different frequencies. The method also includes measuring an electrical signal at a positive terminal and a negative terminal of the energy storage cell, and computing an impedance of the energy storage cell at each of the plurality of different frequencies using the measured electrical signal.