Voltage behavior improvement for proton exchange membrane fuel cell stack suffering fuel starvation

ABSTRACT

Fuel starvation severely affects the performance and durability of proton exchange membrane fuel cell stack. In this paper, the individual voltage characteristics of a 40-cell proton exchange membrane fuel cell stack under different load currents were studied in detail. The cell voltage oscillation, plunge and polarity reversal were observed. To alleviate the hydrogen concentration loss, an effective and simple hydrogen supply method, dual-path hydrogen provision (DHP), was proposed. In the proposed method, high-pressure hydrogen could be fed to the stack from the anode outlet in addition to the anode inlet. An experiment with identical conditions was carried out. It was found that the proposed mitigation measure could significantly alleviate voltage degradation and delay the polarity reversal. The overall output performance of the PEMFC stack was improved by 13.7%, and the maximum improvement of the individual cell was 664%. This paper contributes to a better understanding of the voltage behavior of fuel cells under fuel starvation and provides an effective, practical and low-cost migration measure for most of the commercial PEMFC stack.

KEYWORDS:

• PEMFC stack
• voltage behavior
• fuel starvation
• mitigation

Nomenclature

PEMFC	=	Proton exchange membrane fuel cell
DHP	=	Dual-path hydrogen provision
MEA	=	Membrane electrode assembly
EOD	=	Electro-osmotic drag
E0	=	Standard electrode potential
RHE	=	Reference hydrogen electrode
Pup	=	Hydrogen partial pressure in the upstream region
Pmid	=	Hydrogen partial pressure in the midstream region
Pdow	=	Hydrogen partial pressure in the downstream region
P1’	=	Hydrogen partial pressure in the 1ʹ pipeline
P3ʹ’	=	Hydrogen partial pressure in the 3ʹ’ pipeline
VIR	=	Voltage improvement rate
En	=	Voltage of No.n cell under original operating condition
En’	=	Voltage of No.n cell under DHP method

Superscripts

an	=	Anode
ca	=	Cathode

Subscripts

n

=

Number of the single cell

Additional information

Funding

This research was supported by the National Nature Science Foundation of China (21776095), the Guangdong Province Science and Technology Program (No. 2015B010135007), the Guangzhou Science and Technology Program (No. 201804020048).

Notes on contributors

Zipeng Huang

Zipeng Huang (1996-), Ph.D. candidate of School of Mechanical and Automotive Engineering, South China University of Technology, Guanzhou, Guangdong, mainly engaged in PEMFC heat and mass transfer.

Jing Zhao

Jing Zhao (1993-), Ph.D. candidate of School of Mechanical and Automotive Engineering, South China University of Technology, Guanzhou, Guangdong, mainly engaged in PEMFC heat and mass transfer.

Qifei Jian

Qifei Jian (1963-), Professor of School of Mechanical and Automotive Engineering, South China University of Technology, Guanzhou, Guangdong, mainly engaged in fluid dynamics simulation and fuel cell technology.