Kjeang Erik, Michel Raphaelle, Harrington David A, Djilali Ned, Sinton David
Department of Mechanical Engineering, Institute for Integrated Energy Systems (IESVic), University of Victoria, 3800 Finnerty Road, Victoria, BC, V8W2Y2, Canada.
J Am Chem Soc. 2008 Mar 26;130(12):4000-6. doi: 10.1021/ja078248c. Epub 2008 Mar 4.
A microfluidic fuel cell architecture incorporating flow-through porous electrodes is demonstrated. The design is based on cross-flow of aqueous vanadium redox species through the electrodes into an orthogonally arranged co-laminar exit channel, where the waste solutions provide ionic charge transfer in a membraneless configuration. This flow-through architecture enables improved utilization of the three-dimensional active area inside the porous electrodes and provides enhanced rates of convective/diffusive transport without increasing the parasitic loss required to drive the flow. Prototype fuel cells are fabricated by rapid prototyping with total material cost estimated at 2 USD/unit. Improved performance as compared to previous microfluidic fuel cells is demonstrated, including power densities at room temperature up to 131 mW cm-2. In addition, high overall energy conversion efficiency is obtained through a combination of relatively high levels of fuel utilization and cell voltage. When operated at 1 microL min-1 flow rate, the fuel cell produced 20 mW cm-2 at 0.8 V combined with an active fuel utilization of 94%. Finally, we demonstrate in situ fuel and oxidant regeneration by running the flow-through architecture fuel cell in reverse.
展示了一种包含流通式多孔电极的微流控燃料电池架构。该设计基于钒氧化还原水性物质通过电极的错流，进入正交排列的共层流出口通道，在无膜配置中，废溶液提供离子电荷转移。这种流通式架构能够提高多孔电极内部三维活性区域的利用率，并在不增加驱动流体所需寄生损耗的情况下提高对流/扩散传输速率。通过快速成型制造的原型燃料电池，估计单位材料成本为2美元。与之前的微流控燃料电池相比，性能得到了改善，包括室温下高达131 mW cm-2的功率密度。此外，通过相对较高水平的燃料利用率和电池电压的组合，获得了较高的总能量转换效率。当以1 μL min-1的流速运行时，燃料电池在0.8 V时产生20 mW cm-2，活性燃料利用率为94%。最后，我们通过反向运行流通式架构燃料电池，展示了原位燃料和氧化剂再生。
