US 12,142,802 B2
Electrochemical impedance spectroscopy (“EIS”) analyzer and method of using thereof
Karthick Sudhan S, Mumbai (IN); Bhavana Ganesh, Bangalore (IN); Abhishek Dudhmande, Thane West (IN); Ranganathan Gurunathan, Bangalore (IN); and Ian Russell, Sunnyvale, CA (US)
Assigned to BLOOM ENERGY CORPORATION, San Jose, CA (US)
Filed by BLOOM ENERGY CORPORATION, San Jose, CA (US)
Filed on Apr. 15, 2022, as Appl. No. 17/722,059.
Application 17/722,059 is a division of application No. 16/799,371, filed on Feb. 24, 2020, granted, now 11,335,928.
Application 16/799,371 is a division of application No. 14/853,030, filed on Sep. 14, 2015, granted, now 10,573,910, issued on Feb. 25, 2020.
Prior Publication US 2022/0246962 A1, Aug. 4, 2022
Int. Cl. H01M 8/04537 (2016.01); H01M 8/04298 (2016.01); H01M 8/04664 (2016.01); H01M 8/04746 (2016.01); H01M 8/04858 (2016.01); H01M 8/04992 (2016.01)
CPC H01M 8/04649 (2013.01) [H01M 8/04305 (2013.01); H01M 8/04589 (2013.01); H01M 8/04679 (2013.01); H01M 8/04753 (2013.01); H01M 8/0491 (2013.01); H01M 8/04992 (2013.01)] 10 Claims
OG exemplary drawing
 
1. A method of monitoring a fuel cell system performed by a controller of the fuel cell system, comprising:
determining an impedance of a set of fuel cells using electrochemical impedance spectroscopy;
determining an ohmic polarization of the set of fuel cells from the impedance;
determining a concentration polarization of the set of fuel cells from the impedance;
comparing the ohmic polarization of the set of fuel cells to a first threshold;
comparing the concentration polarization of the set of fuel cells to a second threshold; and
initiating a corrective action when the ohmic polarization crosses the first threshold or when the concentration polarization crosses the second threshold,
wherein the corrective action comprises one or more of initiating a stack recovery sequence, varying fuel supplied to the set of fuel cells, varying output current from the set of fuel cells, adjusting a component in the fuel cell system, and sounding an alarm for an operator to take action.