“With ample supply of oxygen from the atmosphere, metal-air batteries have drastically higher theoretical energy density than either traditional aqueous batteries or lithium-ion batteries. Among them, zinc-air is technically and economically the most viable option,” says Hongjie Dai, a professor of chemistry at Stanford and lead author of the study.
Dai says that metal-air batteries, such as the zinc-air, have a drastically higher energy density because oxygen is abundant in the atmosphere. “Among them, zinc-air is technically and economically the most viable option,” he adds.
How Zinc-Air Batteries Work’
Zinc-air batteries use the oxygen found in the atmosphere with zinc metal in a liquid alkaline electrolyte to generate electricity. The only byproduct is zinc oxide, which is decomposed into oxygen and zinc metal during the recharging process.
Moreover, aqueous electrolytes are not flammable, which makes the zinc-air battery safer to operate than lithium ion (very flammable in contact with air).
What this group has come up with for zinc-air batteries are performance-boosting catalysts. “A combination of a cobalt-oxide hybrid air catalyst for oxygen reduction and a nickel-iron hydroxide hybrid air catalyst for oxygen evolution resulted in a record high-energy efficiency for a zinc-air battery, with a high specific energy density more than twice that of lithium-ion technology.”
They also demonstrated a good stability and reversibility over long charge and discharge cycles that they performed during several weeks.
This may mean that in 10 years we’ll be able to charge our cars in 5 minutes and go some 600 miles on a charge… (sounds too good to be true?)