Flexible direct formate paper fuel cells with high performance and great durability

Paper-based microfluidic fuel cells are prominent in flexible electronics, including wearable and disposable devices, such as smart packages and point-of-care diagnostics. However, the performance is generally low, and the long-term durability is questionable. In this work, we propose a flexible paper-based fuel cell with a novel cell architecture that adopts a single flow for the delivery of both the fuel and the supporting electrolyte. During cell operation, the anode is immersed in a liquid fuel with a supporting electrolyte, while the cathode is exposed to the ambient air. The performance of this cell is increased by one order of magnitude compared to the conventional co-flow cell architecture due to the enhanced mass transfer. A maximum power density of similar to 20 mW/cm(2) and a maximum current density of 122.9 mA/cm(2) are achieved, which are the highest among all reported paper based direct formate fuel cells. Furthermore, this cell can steadily discharge at 5 mA cm(-2) for more than 10 days continuously, while the morphology of the anode and the cathode before and after cell operation remains unchanged. Finally, this paper-based fuel cell can be efficiently fabricated by 3D printing, which is simple, low cost, and advantageous for paper-based fuel cell fabrication.

Automated summary

A flexible paper-based fuel cell with a novel cell architecture has been proposed in this research, showing significantly improved performance compared to traditional cells with a maximum power density and current density achieved at high levels. The cell also demonstrates stable long-term discharge capabilities and can be efficiently manufactured through 3D printing.