Hrl Laboratories, LLC

Gm Global Technolgoy Operations, Inc.

Luan Vu

Shuoqin Wang

Mark William Verbrugge

Qin Jiang

Charles Weldon Wampler, Ii

A number of illustrative variations may include a method, which may include obtaining terminal voltage data of a electrochemical device; determining an equivalent circuit model which operates in a manner approximating the terminal voltage data comprising an open circuit voltage Vcomprising a constant voltage source Vand a voltage Vacross a capacitor C, in series with an overpotential circuit comprising an overpotential voltage V; determining at least one of the power capabilities of the equivalent circuit model; and, estimating at least one of the power capabilities of the electrochemical device based upon the determined power capabilities of the equivalent circuit model.

Electrochemical device power estimator and methods of making and using the same

A method for dynamic characterization of an electrochemical system (such as a lithium-ion battery) is provided, comprising exciting an electrochemical system with a plurality of double-pulse sequences, each comprising a constant-current discharge pulse, a constant-current charge pulse having the same pulse width and pulse amplitude, and a zero-current period between the pulses; and calculating an impulse response, using a recursive or matrix-based method, to dynamically characterize the electrochemical system. A constant state-of-charge is maintained in the electrochemical system. Therefore the signal-to-noise ratio is high due to the repetition of the driving sequence. This method may be employed for on-line determination of the impedance spectrum of an electrochemical system, since the cycling profile can be easily integrated into charge/discharge profiles. Batteries (and other devices) can be diagnosed at high speed and with high accuracy. The double-pulse sequence is robust for fairly noisy systems.

Double-pulse technique for on-line diagnostics of electrochemical systems

Some variations provide a method for real-time estimation of state of charge and state of power of a battery, comprising: (a) cycling a battery with a driving profile; (b) utilizing a recursive algorithm that relates battery terminal voltage to battery current, wherein the algorithm includes open-circuit voltage and a finite-impulse-response filter to dynamically model kinetic voltage; measuring the battery terminal voltage and the battery current at least at a first time and a second time during cycling; calculating battery open-circuit voltage and finite-impulse-response filter parameters; calculating battery state of charge based on the open-circuit voltage; and calculating battery state of power based on the open-circuit voltage and the finite-impulse-response filter parameters. An extended Kalman filtering technique is incorporated for real-time updating of FIR model parameters. Only a single FIR filter is necessary, making these methods applicable for battery-powered systems with limited computing and storage capabilities.

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Midway City, CA, United States of America

Luan Vu