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DOE OSTI · 1892761

Methods and algorithms of cyclic coulometry

Weiss, Steven E.·Lemay, Charles R.·Ferencz, Andrew
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Abstract

Systems, devices, and methods of diagnosing an electrochemical cell using cyclic coulometry are discussed. An exemplary battery diagnostic system comprises a current generator to generate symmetric charge current and discharge current to excite an electrochemical cell, and a cyclic coulometer to evaluate performance of the electrochemical cell. The cyclic coulometer can adjust at least one of a charge time for applying the charge current, or a discharge time for applying the discharge current, to keep a monitored cell voltage toward a specific setpoint. The adjustment of charge or discharge time can be achieved by changing a current switch timing for reversing current from a first to a second current direction. The cyclic coulometer measures one or more electrical parameters during the charge or discharge cycle, and generates a performance metric using the measured electrical parameters.

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Weiss, Steven E., Lemay, Charles R., Ferencz, Andrew. 2022-03-29. Methods and algorithms of cyclic coulometry. https://www.osti.gov/biblio/1892761

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