Modeling And Fabricationf Technology Of Flexible Membrane Electrode For Micro Direct Methanol Fuel Cell

With the progress of society and human needs,flexible electronics that can work under long-term bending conditions appear and develop rapidly.At the same time,it also brings flexibility requirements for batteries.Micro Direct Methanol Fuel Cell(μDMFC)Because of the advantages of high energy density and easy portability of fuel,it is widely used in military and daily life.The realization of the flexibility ofμDMFC is of great significance to the development of flexible electronics.This paper mainly studies the realization of the flexibility of the membrane electrode,the core functional component ofμDMFC.This paper uses COMSOL software to establish a simulation model of flexible membrane electrodes,and explores the influence of membrane electrode bending on battery performance.On the one hand,it will reduce the contact resistance between the membrane electrode and the current collector.On the other hand,it will also cause the cathode and anode.The uneven current density distribution brings a small drop in the overall current density of the membrane electrode,which confirms the possibility of flexible operation of the membrane electrode.The model was used to simulate the performance changes of the membrane electrode under different compression levels.The results showed that as the compression level increases,the output power density of the battery also shows a trend of first increasing and then decreasing.Then the preparation process of the flexible membrane electrode was established,and the parameters of the preparation process were optimized on the basis of simulation.The experimental results showed that the total load of Pt Ru at the anode was 3 mg/cm~2,the Pt load at the cathode was 2 mg/cm~2,and the compression ratio At37.5%,the carbon cloth film electrode has the best performance.The maximum output power density at 60°C is 42.16 m W/cm~2,and the maximum output power density at 30°C is 29.20 m W/cm~2.This paper compares the performance of carbon cloth membrane electrode and carbon paper membrane electrode.The performance of carbon cloth membrane electrode is slightly lower than that of carbon paper membrane electrode before bending.After repeated bending tests,obvious physical damage occurred on the surface of the carbon paper membrane electrode,the open circuit voltage was significantly reduced,and the performance was also greatly reduced,reaching a maximum of 74.23%.However,after the carbon cloth membrane electrode was bent many times,the membrane electrode had no obvious physical appearance change,the open circuit voltage increased,and the output power density remained basically unchanged.After the bending test,the performance of the carbon cloth membrane electrode is much better than that of the carbon paper membrane electrode.It is proved that carbon cloth is more suitable as the diffusion layer component of flexible membrane electrode.