Scientists have designed a longer-lasting lithium-oxygen battery
Packing more energy into batteries is the key to delivering electric cars with longer range and smartphones that can last days.
The promise: Lithium-oxygen batteries represent one of the more promising paths toward that end. They could boost energy density by an order of magnitude above conventional lithium-ion batteries—in theory, at least. A paper published yesterday in Scienceaddressed some of the major hurdles to converting that potential into commercial reality.
The challenge: As a lithium-oxygen battery discharges, oxygen is converted into 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 the cathode material, used a molten salt electrolyte, and raised the battery's operating temperature to 150 ˚C, which together made the batteries more resilient to repeated recharging.
Wait for it ... But Linda Nazar, a co-author of the study, stresses that the researchers haven't provided a practical design for commercial production of lithium-oxygen batteries, which she says is at least more than 15 years away. "We may be infinity from commercialization—as our battery is designed—but more importantly this concept will hopefully lead to new designs that may get us there," she said in an email.
—James Temple
