What is Ultrasonic Membrane Electrode Coating?
Proton exchange membrane fuel cells, as a clean emission, efficient, and low-temperature operating power source, have attracted great attention for mobile and stationary applications. In the design of PEMFC, membrane electrode assembly (MEA) is an important component consisting of membrane, electrode, gas diffusion layer (GDLS), and gasket. The membrane electrode assembly technology has a significant impact on the performance and durability of proton exchange membrane fuel cells. The most common MEA manufacturing method relies on the production of catalytic coatings (CCMS) or gas diffusion electrodes (GDES). During the manufacturing process, the anode and cathode layers are applied to the membrane through direct coating or marking transfer.
The basic principle of membrane electrode preparation method is to load catalyst slurry onto the surface of proton exchange membrane or gas diffusion layer, and then laminate the proton exchange membrane, catalytic layer, frame, and gas diffusion layer together by hot pressing or bonding to complete the preparation of membrane electrode. At present, the methods used for catalyst slurry loading include ultrasonic spraying, electric spray, screen printing, transfer printing, brushing, sputtering, electrochemical deposition and direct coating.
The ultrasonic coating system can produce highly durable and uniform carbon based catalyst ink coatings during the electrolysis process of fuel cells and proton exchange membrane (PEM) electrolyzers such as Nafion, without causing membrane deformation. In PEM fuel cells GDL, When depositing homogeneous catalyst coatings on electrodes, various electrolyte membranes, and solid oxide fuel cells, it is necessary to use a spray suspension containing carbon black ink, polytetrafluoroethylene binder, ceramic slurry, platinum, and other precious metals. Other metal alloys, including metal oxide suspensions in platinum, nickel, iridium, and ruthenium fuel cell catalyst coatings, can also be manufactured through ultrasonic spraying to produce PEM fuel cells, polymer electrolyte membrane (PEM) electrolytes, DMFC (direct methanol fuel cells), and SOFC (solid oxide fuel cells), resulting in high load and high cell efficiency.
Advantages of Ultrasonic Membrane Electrode Coating:
The membrane electrode prepared by ultrasonic spraying method has high automation, high efficiency, low manufacturing cost, and can meet the requirements of quantitative production. The utilization rate of platinum in the membrane sprayed by ultrasonic can reach about 90%, reducing material consumption and thus saving the use of expensive catalyst ink. After years of experimental research on ultrasonic waves, ultrasonic spraying equipment has been developed to prepare membrane electrodes through ultrasonic spraying.
