A dual-electrolyte aluminum/air microfluidic cell with enhanced voltage, power density and electrolyte utilization via a novel composite membrane.

A dual-electrolyte aluminum/air microfluidic cell is a promising power source with remarkably higher power density than traditional aluminum/air cells. However, the crossover between the acidic catholyte and the alkaline anolyte is still a serious issue leading to low electrolyte utilization. In this work, we present a dual-electrolyte aluminum/air microfluidic cell with a novel porous composite membrane based on a polytetrafluoroethylene/polyethylene/polytetrafluoroethylene sandwich structure, with which a stable open-circuit voltage as high as 2.18 V is reached during all the 10 cycles of electrolytes. The electrolyte utilization is also evaluated theoretically, which exhibits a drastic enhancement from 2.24% to 24.34% at cycle infinity with the existence of the composite membrane. Compared to traditional single electrolyte aluminum/air cells or aluminum/air microfluidic cells, this new type of cell not only achieves a high voltage and a high power density, but also shows outstanding recirculating performance of the electrolytes by taking advantages of both the co-laminar flow and the porous composite membrane. Therefore, the dual-electrolyte aluminum/air microfluidic cell could be a promising candidate for inexpensive, low frequent applications, such as long-lasting uninterruptible power supply and range extenders. Image 1 • A novel PTFE/PE/PTFE composite membrane is used for the Al/air microfluidic cell. • The membrane effectively suppresses the crossover neutralization of electrolytes. • Cells demonstrate the recirculating performance with a stable V OC as high as 2.18 V. • The electrolyte utilization has a dramatic enhancement and is evaluated theoretically. • The electrolyte utilization increases from 2.24% to 24.34% at infinite cycles. [ABSTRACT FROM AUTHOR]