Unlike a battery cell, fuel cell operates indefinitely and yields only water. A fuel cell is an electrochemical device that generates electricity and heat and is expected to replace lithium batteries. The most promising technology looks to be that of proton exchange membrane which is suitable for 1-50 KW output. The cell uses polymer membrane and conductive plate that divides, reunite proton and electron generating electricity. Many cells would be required to generate sufficient electricity since each cell produces only small amount of current.

The biggest opportunity for plastics in fuel cells is in functional components of the fuel stack and peripheral systems for fuel-cell vehicles and stationary power plants. Thermoset compression molders are pressing developments of plastic fuel stack components, notably bipolar plates (which conduct current), end plates (which support fuel-cell stacks) and seals (which prevent escape of gases from the stack). In fuel cell stacks, bipolar plates serve as both anode for one cell and cathode for the adjoining cell. They are flat, thin and rectangular. What makes them challenging to mould are the 1-mm-wide flow channels machined or moulded into each side to ensure uniform distribution of fuel. Until recently, most plates were machined out of graphite or compression moulded blanks of filled PVDF fluoropolymer. Graphite is highly conductive but also brittle and expensive. Machining is also relatively costly. On the other hand, compression molded thermoset plates with moulded in channels typically cost only about 20% as much as graphite plates. Currently, compression moulding is more viable than injection molding and is likely to remain in the near future. Vinyl ester may have an edge in fuel cell plate development, but other materials are still in contention. Some thermoplastics suppliers hope to see their engineering resins replace thermosets in fuel cell plates, and are grooming products for roles in the support systems of fuel cell devices. However, the high cost of these engineering resins seems to be a prohibitive factor for fuel cell OEMs.

Though forecasts of future demand for fuel cells are highly speculative, the long-term potential for plastics is considerable. Consumption would depend on the specific end market and device sizes, but average fuel-cell stacks are likely to contain around 50 Kg of plastic in bipolar plates and 25 Kg in Peripherals, 25 Kg per fuel-cell unit � thus, every million fuel cells sold could generate demand for at least 100 million Kg.