Voltage Reduction Technique for Use With Electrochemical Impedance Spectroscopy in High-Voltage Fuel Cell and Battery Systems

An attractive application of electrochemical impedance spectroscopy (EIS) is for diagnostics of a fuel cell (FC) or a battery system during operation. The use of EIS, however, is mostly limited to low-voltage (LV) FC systems and laboratory environments. Hence, the application of EIS in advanced diagnostics of a high-power system certainly lacks due to the voltage limitation and/or cost of the equipment. In this paper, a precision, low-cost electronic interface is proposed which enables the use of existing LV ac diagnostic tools with a production-size FC or battery stacks without the need for postprocessing of data. The interface, a dc level reducer (DLR), reduces only the dc component of the stack voltage to a safe voltage of <60 without altering the ac diagnostic components. This paper explains in detail the development of the DLR circuitry. The scalability and real-world capability of the interface are demonstrated by developing it for two voltage ratings. A set of circuits rated for 30 V is tested with a nine-cell proton exchange membrane FC (PEMFC) stack, and circuits rated for 200 V are tested on 90- and 110-cell commercial PEMFC stacks. The stack voltage is reduced by 60% on the nine-cell stack, and 60%–90% on the 90- and 110-cell stacks. The accuracy is measured using EIS data for 74 frequency points in the range of 0.1–20 kHz, with and without the DLR. The maximum relative error for point-versus-point comparison of the impedance is measured at 0.8% and 1.4% for 30- and 200-V rated circuits, respectively. These errors are well within the error of the industrial measurement equipment used, proving the fidelity of the ac signal output from the DLR.

• Record URL:
  https://doi.org/10.1109/TTE.2018.2806090
• Availability:
  • Find a library where document is available. Order URL: http://worldcat.org/issn/23327782
• Supplemental Notes:
  • Copyright © 2018, IEEE.
• Authors:
  • Homayouni, Hooman
  • DeVaal, Jake
  • Golnaraghi, Farid
  • Wang, Jiacheng
• Publication Date: 2018-6

Language

• English

Media Info

• Media Type: Web
• Features: References;
• Pagination: pp 418-431
• Serial:
  • IEEE Transactions on Transportation Electrification
  • Volume: 4
  • Issue Number: 2
  • Publisher: Institute of Electrical and Electronics Engineers (IEEE)
  • ISSN: 2332-7782
  • Serial URL: http://ieeexplore.ieee.org/servlet/opac?punumber=6687316

Subject/Index Terms

• TRT Terms: Diagnostic tests; Electrical impedance; Electrochemical processes; Fuel cell vehicles; Fuel cells; High voltage; Spectroscopy
• Uncontrolled Terms: Proton exchange membrane fuel cells
• Subject Areas: Energy; Highways; Vehicles and Equipment;

Filing Info

• Accession Number: 01679171
• Record Type: Publication
• Files: TRIS
• Created Date: Aug 27 2018 2:05PM