Ultrasonic Spray Systems for Fuel Cell Catalyst Coating – PEM and GDL Manufacturing
Ultrasonic nozzle sytems produce highly durable, uniform, pinhole free coatings of carbon-based catalyst inks onto fuel cell proton exchange membranes such as Nafion, without deformation of the membrane. Other metal alloys, including Platinum, Nickel, Ir, and Ru-based fuel cell catalyst coatings of metal oxide suspensions can be sprayed using ultrasonics for manufacturing PEMs, GDLs, DMFCs (direct methanol fuel cells) and SOFCs (solid oxide fuel cells) to create maximum load and high cell efficiency. Sono-Tek ultrasonic nozzles are used by some of the largest fuel cell manufacturers in the world for spraying uniform thin film layers of catalyst inks. Research has proven Platinum yield in membranes coated using ultrasonic spray are up to 95%. For more information regarding research papers on this topic, go to http://www.sono-tek.com/application-specific-research-papers/.
The uniform thin film coating achieved with ultrasonics retains the porosity of the electrode and does not impede the transport of reactants due to flooding of the electrode surface. Catalyst solutions will not clog the ultrasonic nozzle, allowing for uniform, homogeneous fuel cell catalyst coatings with controlled droplet sizes at ultra-low flow rates.
For a more comprehensive video illustrating Sono-Tek’s ultrasonic technology for fuel cell manufacturing, go to https://s3.amazonaws.com/video.sono-tek.com/mp4/FC_r6.mp4
Ultrasonic nozzle benefits for spraying catalyst inks:
- Up to 80% reduction in material consumption, conserving expensive inks
- Reduced wasteful overspray
- Spray patterns that are easily shaped for precise coating applications
- Highly controllable spray that produces reliable, consistent results
- Non-clogging atomized spray
- Ultra-low flow rate capabilities, intermittent or continuous
- Ultrasonic vibrations continuously deagglomerate particles and keep them evenly dispersed
Sono-Tek is well known for our highly durable, pinhole-free ultrasonic catalyst coatings onto Nafion fuel cells, with ultrasonic technology systems installed in some of the largest alternative energy manufacturers in the world. In addition, Sono-Tek ultrasonic nozzles are well suited to spraying polymer solutions such as PTFE binder onto GDLs to enhance hydrophilic or hydrophobic properties in electrolyzing processes.
The above image illustrates the ideal dispersion of carbon platinum in the catalyst coating on the left, as achieved with ultrasonic coating, and problematic agglomerates and voids on the right. Breaking up agglomerates into evenly dispersed catalyst layers using ultrasonic spray results in higher electrochemical performance and greater repeatability of functional coatings.
With over 30 years of industry leadership in ultrasonic spray technology, Sono-Tek has the experience to help you integrate our technology into your application. In-house laboratory testing is available to aid in determining the best technology solution for each customer’s unique process. The expertise of our engineering staff gives us the ability to help customers solve process issues to develop systems that meet the needs of each unique application. From R&D applications to high volume manufacturing, Sono-Tek offers full coating solutions with state-of-the-art design and unsurpassed customer service.