Calculating Time constant in battery from voltage data ?

Praveen Kumar Kuppusamy @Praveen_Kuppusamy

05 May 2017 1 9K Report

I am using A123 26650 LFP battery. How do I calculate the time constants (tau) from Voltage time graph of battery. I am using 2RC equivalent ckt model.

Thanks

Jerry Decker

Correlate with a exponential decay function and the time constant is generated as the coefficient of ( 1 / t ) in the exponent. You get a different constant if the battery is vibrated during the discharge, also if starting temperature is different. Testing should follow one of the standard methods.

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