The team consists of the following members: Hongjie Dai, a professor of chemistry, Yanguang Li (lead author), Ming Gong, Yongye Liang, Ju Feng, Ji-Eun Kim, Hailiang Wang, Guosong Hong and Bo Zhang.
According to Dai, the attention nowadays is focused on lithium-ion batteries, despite their limited energy density (energy stored per unit volume), high cost and safety problems. As a contrast, the zinc-air batteries have much higher theoretical energy density and are much less expensive than the most common batteries at present.
The process of generating electricity is performed bonding oxygen from the air and zinc metal in a liquid electrolyte, which leads to zinc oxide synthesis. When the reaction is reversed during recharging, zinc and oxygen are regenerated.
Dai’s group had to invent new, high-performance electrodes because normally the reaction flows too slowly. They used nanotechnology to develop improved catalysts made of cobalt oxide, a nickel-iron compound and carbon nanomaterials. The newly invented catalysts have higher activity and greater durability than conventional electrodes made of different expensive materials such as platinum and iridium.
“Zinc-air batteries are attractive because of the abundance and low cost of zinc metal, as well as the non-flammable nature of the aqueous electrolytes, which make the batteries inherently safe to operate,” Dai said. “Primary (non-rechargeable) zinc-air batteries have been commercialized for medical and telecommunication applications with limited power density. However, it remains a grand challenge to develop electrically rechargeable batteries, with the stumbling blocks being the lack of efficient and robust air catalysts, as well as the limited cycle life of the zinc electrodes.”
The research was supported by Intel , the Stanford Global Climate and Energy Project and a Stinehart/Reed Award from the Stanford Precourt Institute for Energy. https://energy.stanford.edu/
via: [stanford.edu]
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