Slashdot Mirror
Scientists Deliver a Longer-Lasting Lithium-Oxygen Battery (technologyreview.com)
Packing more energy into batteries is the key to delivering electric cars with longer range, smartphones that can last days -- and cheaper electronic products all around. Lithium-oxygen batteries represent one of the more promising paths toward that end. From a report: They could boost energy density by an order of magnitude above conventional lithium-ion batteries -- in theory, at least. In a paper published this week in Science journal, researchers at the University of Waterloo identified ways of addressing some of the major hurdles to converting that potential into commercial reality.
A critical problem has been that as a lithium-oxygen battery discharges, oxygen is converted into superoxide and then lithium peroxide, reactive compounds that corrode the battery's components over time. That, in turn, limits its recharging ability -- and any real-world utility. To get around the problem, researchers switched from a carbon cathode to one made of nickel oxide and supported by a stainless steel mesh. They also used molten salt for the electrolyte -- the part of the battery that allows positively charged ions to move between the electrodes -- and raised the battery's operating temperature to 150C. Those steps made it possible to achieve about three times the number of charging cycles as earlier lithium-oxygen efforts. The researchers also managed to increase the energy per unit of mass by more than 50 percent.
A critical problem has been that as a lithium-oxygen battery discharges, oxygen is converted into superoxide and then lithium peroxide, reactive compounds that corrode the battery's components over time. That, in turn, limits its recharging ability -- and any real-world utility. To get around the problem, researchers switched from a carbon cathode to one made of nickel oxide and supported by a stainless steel mesh. They also used molten salt for the electrolyte -- the part of the battery that allows positively charged ions to move between the electrodes -- and raised the battery's operating temperature to 150C. Those steps made it possible to achieve about three times the number of charging cycles as earlier lithium-oxygen efforts. The researchers also managed to increase the energy per unit of mass by more than 50 percent.
It's another basic science press release! A molten salt battery, Yet somehow it runs at 150C, so salt doesn't mean NaCl, which melts at 801 degrees centegrade. And it's corrosive and eats itself. OK, lead-acid batteries are too, but there's some significant technology to get past, and this is still just a research project. Also, I'm wondering what heating up the whole battery to 150 C to start your car will look like, and what sort of battery you will need to do that. Obviously not the same battery.
Wake me up when I can buy one off the shelf, OK?
Bruce Perens.
Why would a car manufacturer keep a battery of the same size with 10x the density, knowing that charging that battery would be a problem?
They could always just make a battery pack that gives X range, and keep the charging the same for the value of X, but with a much smaller pack (less mass)
Slashdot still doesnâ(TM)t support Unicode after it was added to the HTML standard in 1997.
Because with a 150C battery in it, you don't dare pick it up to use it.
Meh. That's Prior Art for Samsung.
If it weren't for deadlines, nothing would be late.