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AFC Energy’s electrode has been engineered to be produced at low cost without being detrimental to operating efficiency. Precious metals have been almost eliminated and all materials have at least a 50 year security and multiple source of supply.
The AFC Energy electrodes are based on new advanced manufactured materials that have unique properties required for optimum operation and extreme low costs as follows:
- The substrate material consists of a layer of specially manufactured non-woven plastic material that is first coated with a metallic layer;
- This base layer is then used as the foundation for a number of critical material depositions that include the catalysts and conductor layers.
- These materials are extremely thin and are highly accurately distributed onto the substrates to form a homogenous layer.
The level of accuracy combined with the thin layer construction makes for superior access by both the oxygen, hydrogen, and electrolyte via the conductor paths. This results in a highly effective but ultra low cost electrode construction that allows for further system improvements to be implemented.
The typical standard three part alkaline fuel cell electrode of old was typically 1.5mm thick, whilst AFC Energy’s present new electrode design is just 200 microns in section.
Figure A: Conventional gas diffusion electrode
Figure B: Structure of new generation porous electrode for gaseous reactants (AFC Energy concept)
In addition to the low cost materials, AFC Energy has utilised existing manufacturing techniques to keep production simple and cheap. An added advantage of the AFC Energy construction is that because the plastic substrate is so thin, the electrode can be positioned in the cell such that the catalyst material resides on the gas side of the electrode and still enjoys complete and direct access to the electrolyte.
Design Advantage
The distinct advantage of this design feature is that the catalyst material is no longer in direct contact with the electrolyte flow and this reduces the loss of catalyst material through abrasion. In addition, it prevents catalyst flooding due to over-wetting of the electrode. A patent related to this process has been applied for. | 
