阳极流场结构对直接甲醇燃料电池性能影响研究

Influence of Anode Flow Field on the Performance of Micro Direct Methanol Fuel Cell

直接甲醇燃料电池(DMFC)以其能量密度高、环境友好、结构简单和储存携带方便等优点在便携式产品领域得到广泛关注。流场结构设计是否合理是影响燃料电池输出性能的关键因素之一。本文采用非均衡流场的设计思路,对比了非均衡蛇形流场和均衡蛇形流场的DMFC输出性能。实验结果表明,非均衡蛇形流场结构能够提高DMFC的输出性能,当DMFC水平放置时,非均衡蛇形流场的DMFC峰值功率比均衡蛇形流场的DMFC提高33%左右;均衡蛇形流场的DMFC竖直方式放置时,其输出性能比水平放置时有明显提高,而非均衡蛇形流场的DMFC竖直方式放置时,其输出性能与水平放置时相差不多。

Recently, the direct methanol fuel cell （DMFC） has been drawing an increasing attention of researchers to the power applications of advanced portable electronics, because of its advantages such as high theoretical power density, good efficiency,relatively simple system features and convenience in use. The design of its flow field is one of key factors for DMFC performance. In this paper, a non-equipotent flow field, with the channel width being gradually changed along the channel length, is designed. Transparent DMFCs with different flow fields are designed and fabricated. The performance of DMFC with a non-equipotent serpentine flow field is compared to that with the equipotent serpentine flow field. And the performance of DMFCs placed in the horizontal and vertical directions is compared. Results show that the power difference between the DMFC with the non-equipotent serpentine flow field and that with the equipotent serpentine flow field is enlarged with the increase of the fuel cell current. The absolute peak power of the DMFC with the non-equipotent serpentine flow field, placed in the horizontal direction, is about 33% higher than that with the equipotent serpentine flow field. It is also found that the performance of the DMFC with the equipotent serpentine flow field is improved significantly while being placed in the horizontal direction as compared to that in the vertical direction. But the performances of the DMFC with the non-equipotent serpentine flow field are almost the same when it is placed in either directions.