Some even employ proton exchange membranes that move charge around the way a hydrogen fuel cell does.

FORBES

The main electrolytes used today are alkali, molten carbonate, phosphoric acid, proton exchange membrane and solid oxide.

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It also develops its own PEM (proton exchange membrane) fuel cell generators and has a growing business in China, where it will power the buses for the 2008 Beijing Olympics.

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The film, a so-called proton exchange membrane, is delicate.

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There are two dominant flavors of fuel cell: proton-exchange membrane (PEM) and solid oxide.

FORBES: Magazine Article

The energy stored in xylose splits water molecules, yielding high-purity hydrogen that can be directly utilized by proton-exchange membrane fuel cells.

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The authors believe their system could combine the advantages of methanol as a hydrogen carrier and of proton-exchange membrane (PEM) fuel cells for efficient energy production.

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But until recently they have suffered from a low power-to-weight ratio, unlike the other sort of room-temperature fuel cell, the temperamental and costly proton-exchange-membrane device, which several firms hope soon to use in motor cars.

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