微型直接甲醇燃料电池阳极流场结构

针对微型直接甲醇燃料电池(DMFC)阳极传质效率低和性能差等问题,对DMFC阳极流场结构进行了研究.利用MEMS技术实现了具有点形、平行和蛇形等阳极流场结构的硅基自呼吸式DMFC,测试对比结果表明单蛇形流场结构性能要优于其他几种流场;另外,对单蛇形流场结构参数进行了优化,结果表明当流道宽度∶脊的宽度∶流道长度为2∶3∶254时,电池性能达到最佳.在此基础上,为了改善反应物到催化层的传质效率和提高性能,提出了一种渐缩式单蛇形流场结构,其电池最大输出功率密度达到15.41 mW/cm2,比传统等宽式单蛇形流场提高了将近35%,为便携式微能源系统的应用开发奠定了基础.

Anode Flow Field Structures of Micro Direct Methanol Fuel Cell

To improve the low mass transfer efficiency and poor performance of micro direct methanol fuel cells（DMFCs）,a detailed study on the micro direct methanol fuel cell flow field structure is conducted in this paper.Firstly,silicon-based self-breathing DMFCs with the gird,parallel and serpentine anode flow fields were fabricated using MEMS technology.The results show that the cell performance with the single-serpentine flow field is better than those with the other structures.In addition,the single-serpentine flow field parameters were optimized,which shows that when the flow channel width∶the ridge width∶the flow channel length is 2∶3∶254,the optimum cell performance is realized.To achieve both higher mass transfer efficiency of the reactants to catalyst layer and better performance,a self-breathing DMFC with tapered serpentine anode flow fields was proposed.The results demonstrate that the maximum output power density is 15.41 mW/cm2 with the increment of 35% compared with traditional aequilatus single-serpentine flow field,which will contribute to the further development of portable micro power source systems.