扩散层PTFE载量对被动式直接甲醇燃料电池性能的影响

Effect of PTFE contents on performance of a passive DMFC in diffusion layer

在被动式直接甲醇燃料电池(DMFC)的扩散层中,处理好水、气、电子的通道对电池性能有着十分重要的作用。本研究分别用质量百分比浓度为10%、20%、30%、40%的PTFE乳液进行疏水处理的碳布组装成被动式DMFC以及测试系统。通过稳态电流-电压极化曲线法和交流阻抗法,研究了扩散层中的不同PTFE载量对被动式DMFC电化学性能的影响。研究结果表明,电池开路电压随着阳极扩散层中PTFE载量的增加而上升,电池内阻也随着扩散层中PTFE载量的增加而增加。在阳极,电池性能随着扩散层中PTFE载量的增加而下降,在阴极,用10%PTFE乳液处理的碳布对被动式DMFC性能表现最好。

It was very important role for diffusion layer of a passive DMFC to deal well with the channels of water,gas and electron. The carbon cloth were teflonated by different PTFE emulsion concentration（10%, 20%, 30%, 40%）, and a passive DMFC system was installed. The effect of the PTFE contents on the electrochemical performance of a passive DMFC in diffusion layer were investigated by means of steady-state galvanostatic polarization and electrochemical impedance spectroscopy（EIS） . The experimental result showed that the open circuit voltage（OCV） increase with the improvement of the PTFE contents in anode diffusion layer,and the cell resistance increases with the improvement of the PTFE contents in diffusion layer. The performance of a passive DMFC decrease with the increasing PTFE contents in anode diffusion layer. The carbon cloth with 10%PTFE had the best performance of a passive DMFC in cathode diffusion layer.