fuel cell membrane outperforms marketplace

The membrane, which operates over a huge temperature range, lasts 3 times longer than similar business products, Fujimoto and his co-authors say inside the Aug. 21 difficulty of Nature electricity.

fuel-cell PEMs (proton-trade membranes) allow the excretion of protons -- the husk, in a sense -- of the cloth imparting the electrons that shape the fuel cell's electric output. If the protons can not bypass without problems in the cellular, the fettered flow reduces the electric output.

currently industrial PEMs in maximum gasoline-cellular-powered automobiles require water, so their operating temperature cannot get higher than water's boiling factor. higher temperatures dry out the membrane, growth cellular resistance and decrease performance, stated Fujimoto.

"part of the issues with the contemporary PEMs is which you need to hydrate the hydrogen gasoline movement for high performance, and the gasoline cellular can not run effectively at temperatures better than the boiling point of water," he said.

"This hassle can be solved by way of using hydrated gasoline streams and having a bigger radiator to more correctly expend waste warmness," Fujimoto persisted. "Automakers are doing this now. however if PEM gasoline cells did not want water to run, it would make things loads simpler."

every other problem is that cloth costs for the cutting-edge membrane of desire can be approximately $250-$500 in step with square meter. "The DOE [Department of Energy] would like to peer $five to $20 a square meter," Fujimoto stated.

Researchers have tried to clear up those issues with a excessive-temperature approach that makes use of phosphoric acid to dope a polybenzimidazole membrane at more than 350 stages Fahrenheit. however the membrane can not function beneath 284 ranges without degrading the phosphoric acid. as a consequence the membrane is incorrect for automobile applications, in which water condensation from cold engine begin-u.s.and other regular reactions on the gasoline cellular cathode inevitably convey the temperature down into unwanted stages that leach the phosphoric acid out of the response.

Now comes the primary ammonium ion-pair gasoline cellular -- created at Los Alamos national Laboratory -- to mix phosphates with the Sandia-patented membrane. The ammonium-biphosphate ion pairs have exhibited strong overall performance over a huge variety of temperatures from 176-320 ranges F, answered properly to modifications in humidity and lasted three instances longer than maximum industrial PEM fuel mobile membranes.

"There probably can be commercial interest on this discovery," Fujimoto stated. "Our polymer consists of a tethered high quality price which interacts extra strongly with phosphoric acid, which improves acid retention. Heating the fuel cell and including humidity does not lessen performance."