A membrane electrode assembly (MEA) is an assembled stack of proton-exchange membranes (PEM) or alkali anion exchange membrane (AAEM), catalyst and flat plate electrode used in fuel cells and electrolyzers.

The membrane electrode assembly (MEA) is the electrochemical heart of fuel cells and electrolysers, where water is split into oxygen and hydrogen in electrolyzers using current and voltage, and where hydrogen is converted into electricity, heat and product water in fuel cells. The ramp-up of the fuel cell and electrolyser economy requires a comprehensive understanding of the optimal, efficient and sustainable production of MEAs.

• It can minimize the gas transmission resistance, so that the reaction gas can smoothly reach the catalyst layer from the diffusion layer to undergo electrochemical reaction.
  
• Form a good ion channel and reduce the resistance of ion transmission.
  
• Form a good electron channel.
  
• The gas diffusion electrode should ensure good mechanical strength and thermal conductivity.
  
• The membrane has high proton conductivity.