Investigation of an electrode reversal method and degradation recovery mechanisms of PEM fuel cell

Considering the high initial cost of proton exchange membrane fuel cells, improving their durability is significant for their commercialization. This work proposes a performance recovery strategy by reversing the cathode and anode (“cathode/anode reversal”) and then operating under a high current density load. It is systematic to investigate the mechanisms of performance recovery due to recovery strategy and the mechanisms of irreversible degradation of cell performance under a dynamic load cycling condition. The experimental results show that the cell performance is significantly improved after implementing the recovery strategy, with recovery rate reaching 54%@800 mA cm−2. The characterization test results show that the mechanisms of performance recovery are mainly the reduction of platinum oxide, the desorption/removal of sulfate, and the removal of accumulated water. The main mechanisms of irreversible performance attenuation are the coarsening of Pt particles, the formation of Pt band, carbon support corrosion, and CL mechanical degradation. The recovery strategy, recovery effect, recovery mechanisms, and irreversible degradation mechanisms that are discussed in this study provide a reference for designing recovery strategies and improving electrode materials and structures.