High-Performance Flexible Direct Methanol Fuel Cell with Homogeneous Anode Gas Diffusion Layer

The rapid development of flexible electronic devices has promoted the dead for flexible power supplies. A flexible direct methanol fuel cell (DMFC) is an ideal power supply for flexible electronics because of its advantages of simple structure and high energy density. However, the performance of flexible DMFCs that have been reported is inferior to that of their traditional counterparts. In this paper, a novel flexible DMFC with ultrathin stainless steel fiber felt as the backing layer/current collector is proposed, which presents a new approach for the structural design of flexible DMFC. Moreover, combining with the homogeneous anode microporous layer composed of superhydrophilic nitrogen-doped carbon aerogel and Nafion, the novel anode gas diffusion layer based on the hydrophilic stainless steel fiber felt improves the two-phase mass transfer in the anode of DMFC, significantly enhancing the cell performance and stability. Consequently, the as-fabricated flexible DMFC achieves exceptional performance in a compact size and simple structure, with a power density reaching 20.6 mW cm –2 at 22 °C. This new flexible DMFC offers a novel pathway for the application of fuel cell.