| CPC G01R 31/392 (2019.01) [H01M 10/48 (2013.01); H01M 2220/20 (2013.01)] | 20 Claims |

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1. A method for diagnosing health of a battery using in-vehicle impedance analysis, the method comprising:
receiving a sensed current measurement for at least one cell of the battery;
generating a current profile as a function of the sensed current measurement, the current profile comprising multiple pulses to a peak current, the multiple pulses having a pulse frequency;
applying a current with the current profile to the at least one cell;
responsive to a pulse in the current profile, receiving a voltage measurement for the at least one cell, calculating a respective impedance for the at least one cell based thereon, the impedance comprising a real component at the pulse frequency and an imaginary component at the pulse frequency, storing the real component at the pulse frequency and the imaginary component at the pulse frequency for the at least one cell, and identifying a battery health problem when either the real component at the pulse frequency exceeds a preprogrammed first threshold for the pulse frequency, or when the imaginary component at the pulse frequency exceeds a preprogrammed second threshold for the pulse frequency;
for each pulse of the multiple pulses in the current profile, repeating the receiving, calculating, storing, and identifying;
calculating an average real component at the pulse frequency; and
identifying the battery health problem further when the real component at the pulse frequency exceeds the average real component at the pulse frequency by more than a first threshold.
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