Gas diffusion layers

Gas diffusion layers (GDLs) perform the significant functions in the proton exchange membrane fuel cells (PEMFCs), such as maintaining the water balance in the membrane electrode assem-bly (MEA) by allowing appropriate amount of water to move in and out from the reaction zone, providing the mechanical sup-port for the MEA and electrical contact between the electrodes and the current collectors. The key characteristics of GDLs include structural design, porosity, hydrophobicity, hydrophilicity, gas permeability/transport properties, watermanagement and surface morphology. The GDLs consist of a micro-porous layer made of teflonized carbon black on the top of macro-porous carbon paperor cloth substrate. The effects of macro-porous carbon substrateon the GDL performance have been reported in our previous study. Alcohol based solvents are widely used for preparing homoge-nous dispersion of teflonized carbon slurries for GDL fabricationof micro-porous layers. However, the alcohols pose environmental and health safety issues when used in large rvolume for any commercial manufacturing.

Application of Ultrasonic Spray Machine in Gas Diffusion Layer (GDL) of Fuel Cells

Gas diffusion layers (GDLs) are key components of fuel cells, responsible for multiple functions such as gas conduction, water management, electronic conduction, and supporting catalytic layers. The quality of the coating directly affects the output performance and service life of the battery. Ultrasonic spraying is an efficient process for preparing GDL coatings.

Ultrasonic spraying uses high-frequency vibration to atomize PTFE lotion and carbon based slurry to form small and uniform micro droplets, which are transported to the surface of carbon paper and carbon cloth substrate with low pressure carrier gas. Non contact spraying will not crush and damage the original porous pore structure of GDL, retain gas diffusion and drainage channels, avoid pore blockage caused by traditional spraying high-pressure air flow, and ensure gas-liquid two-phase transmission efficiency.

The process can accurately control the spraying amount, achieve micrometer level controllable thin coating, evenly distribute the coating, reduce local PTFE agglomeration, ensure gradient distribution of hydrophobic layer, optimize internal water management of fuel cells, and alleviate water flooding problems. High material utilization rate, significantly reducing slurry loss compared to traditional spraying, lowering raw material costs, and adapting to different coating systems such as PTFE hydrophobic coatings and microporous layers.

Selective area spraying can be applied to GDL, meeting the needs of batch sampling and continuous roll to roll production. The spraying process operates at low temperatures, and the substrate is not easily deformed by heat. The coating is tightly bonded to the carbon paper substrate and is not easily peeled off after compression. The formed gas diffusion layer has stable porosity, good consistency in conductivity and hydrophobicity, which helps to improve the output power of fuel cells and reduce the performance variability of individual cells. It is suitable for hydrogen fuel cell research and industrial mass manufacturing.

About Cheersonic

Cheersonic is the leading developer and manufacturer of ultrasonic coating systems for applying precise, thin film coatings to protect, strengthen or smooth surfaces on parts and components for the microelectronics/electronics, alternative energy, medical and industrial markets, including specialized glass applications in construction and automotive.

Our coating solutions are environmentally-friendly, efficient and highly reliable, and enable dramatic reductions in overspray, savings in raw material, water and energy usage and provide improved process repeatability, transfer efficiency, high uniformity and reduced emissions.

Chinese Website: Cheersonic Provides Professional Coating Solutions