Optimization of the efficiency and degradation rate of an automotive fuel cell system. (18th August 2021)

• Record Type: Journal Article
• Authors: Hahn, Sergei; Braun, Jochen; Kemmer, Helerson; Reuss, Hans-Christian
• Is Part Of: International journal of hydrogen energy. Volume 46:Number 57(2021)
• Page Start: 29459
• Page End: 29477
• Publication Date: 2021-08-18
• Subjects: Fuel cell -- Operation strategy -- Optimization -- Efficiency -- Degradation; Hydrogen as fuel -- Periodicals; Hydrogène (Combustible) -- Périodiques; Hydrogen as fuel; Periodicals; 665.81
• DOI: 10.1016/j.ijhydene.2020.12.084
• Languages: English
• ISSNs: 0360-3199

Abstract

Abstract: In this contribution an approach for the analysis of the operation parameters of a fuel cell system is presented, which can be used for a lifetime and efficiency optimization. For this purpose, a physically-based polarization curve model of an automotive fuel cell stack is derived, which enables a realistic simulation study. Furthermore, the influence of degradation based on semi-empirical correlations for the loss of catalytic activity is included. This stack model is combined with a simplified fuel cell system model and used for a subsequent simulation study with focus on the system efficiency on the one hand and the lifetime on the other hand. The results show that an adaption of the operation parameters of the system can partly counteract the deterioration of the efficiency due to degradation. Furthermore, the lifetime of the stack could be enhanced at the cost of lower efficiency. Graphical abstract: The efficiency of a fuel cell system and the rate of loss in electrochemical activity of the fuel cells depend on the operating conditions within the system. An optimization of the cathode stoichiometry λ, the cathode pressure and the operation temperature enables a reasonable trade-off between hydrogen consumption and the degradation rate of the fuel cells. Image 1 Highlights: Aging of the stack leads to a drift of optimal operation parameters. Adaption of operation parameters has potential to improve operation over lifetime. Maximum power of an aged FCS can be increased by about 2%. Efficiency of an aged FCS can be increased by up to 3.5%. Lifetime of a FCS can be improved at the cost of lower efficiency.