Powerful new battery could help usher in a green power grid
http://www.sciencemag.org/news/2018/08/powerful-new-battery-could-help-usher-green-power-grid
Source: By Robert F. Service, Science Magazine.
Excerpt: Lithium-ion batteries power everything from our smartphones to our cars. But one of their most promising replacements is lithium-oxygen batteries, which in theory could store 10 times more power. The only problem: They fall apart after just a handful of charging cycles. Now, researchers have found that running them at high temperatures—along with a couple of other fixes—can push them to at least 150 cycles. Although they would be too hot to handle in phones, lithium-oxygen batteries the size of rail cars could one day underpin a green energy grid, storing excess wind and solar power and delivering it on demand. ... 2 years ago, a team of U.S. researchers came up with the first hints of a breakthrough. They tested another alternative electrolyte, this one made from a combination of salts that turned into a liquid when heated. This molten salt withstood the ravages of Li2O2 and superoxide, but the battery’s carbon-based cathode still fell victim. Now, Nazar and her colleagues have taken another step forward. They kept the molten salt electrolyte but replaced the carbon cathode with a nickel-based version. They also raised the operating temperature of the battery to 150°C. That combination, instead of producing the Li2O2 and superoxide, produces Li2O, a stable compound that doesn’t rip through the electrolyte or anything else. The batteries suffer virtually no degradation out to 150 cycles....
Source: By Robert F. Service, Science Magazine.
Excerpt: Lithium-ion batteries power everything from our smartphones to our cars. But one of their most promising replacements is lithium-oxygen batteries, which in theory could store 10 times more power. The only problem: They fall apart after just a handful of charging cycles. Now, researchers have found that running them at high temperatures—along with a couple of other fixes—can push them to at least 150 cycles. Although they would be too hot to handle in phones, lithium-oxygen batteries the size of rail cars could one day underpin a green energy grid, storing excess wind and solar power and delivering it on demand. ... 2 years ago, a team of U.S. researchers came up with the first hints of a breakthrough. They tested another alternative electrolyte, this one made from a combination of salts that turned into a liquid when heated. This molten salt withstood the ravages of Li2O2 and superoxide, but the battery’s carbon-based cathode still fell victim. Now, Nazar and her colleagues have taken another step forward. They kept the molten salt electrolyte but replaced the carbon cathode with a nickel-based version. They also raised the operating temperature of the battery to 150°C. That combination, instead of producing the Li2O2 and superoxide, produces Li2O, a stable compound that doesn’t rip through the electrolyte or anything else. The batteries suffer virtually no degradation out to 150 cycles....