Stanford scientists develop high-efficiency zinc-air battery

Dean Sigler Electric Powerplants, Sustainable Aviation Leave a Comment

Battery researchers, including those at Stanford University, have been focusing for years on improving lithium batteries of multiple chemistries.  While IBM tries to create the 500-mile battery based on lithium-air reactions, and ReVolt in Portland works on perfecting a long-lasting zinc-air cell, Stanford researcher Hongjie Dai and his team claim to have “developed an advanced zinc-air battery with higher catalytic activity and durability than similar batteries made with costly platinum and iridium catalysts.” The resulting battery, detailed in the May 7 online edition of the journal Nature Communications, could be the forerunner of something with greater endurance and lower cost than current efforts. Mark Schwartz, writing for Stanford, quotes Dai, a professor of chemistry at the University and lead author of the study: “There have been increasing demands for high-performance, inexpensive and safe batteries for portable electronics, electric vehicles and other energy storage applications.  Metal-air batteries offer a possible low-cost solution.” Lithium-ion batteries, despite their limited energy density (energy stored per …

Imperfect Carbon as Good as Pricy Platinum

Dean Sigler Electric Powerplants, Sustainable Aviation Leave a Comment

The expense of platinum catalysts has been an impediment to the development of fuel cells and metal-air batteries.  Scientists at Stanford University may have found an inexpensive, higher-performance alternative in “unzipped” carbon nanotubes that show an imperfect face to the world. Findings published in the May 27 online version of the journal Nature Nanotechnology quote chemistry professor Hongjie Dai, co-author of the paper.  “Platinum is very expensive and thus impractical for large-scale commercialization. Developing a low-cost alternative has been a major research goal for several decades.” With platinum ranging from almost $800 to over $2,200 an ounce, carbon nanotubes, with their conductivity and inexpensive production costs provide a desirable combination of performance and price. Nanotubes are rolled-up sheets of graphene, a one-atom thick layer of pure carbon – 10,000 times narrower than a human hair. Dai’s team nested two or three nanotubes, each smaller than the next layer outward, an amazing feat considering the submicroscopic size of the tubes.   To …