Put more energy into batteries is the key to creating electric vehicles with a longer run, smartphones with “eternal” charge and cheap electronics around and everywhere. Lithium-oxygen batteries are one of the most promising ways of development in this direction. They can increase the energy density by several orders of magnitude in comparison with traditional lithium-ion batteries – at least in theory. In a paper published yesterday in the journal Science, scientists from the University of Waterloo figured out how to solve the biggest obstacles to the formation of these batteries as a commercial reality.
What was the catch? Most importantly: when lithium-oxygen batteries were discharged, oxygen was converted to superoxide and then into lithium peroxide, reactive components that corroded the battery over time. This, in turn, limited its ability to recharge – and a possible useful application.
When will we have better batteries?
What has changed? To solve this problem, scientists have moved from a carbon cathode to a nickel oxide cathode with the support of a stainless steel mesh. Also, the electrolyte used was a fused salt – the electrolyte allows the positively charged ions to move between the electrodes – and raised the operating temperature of the battery to 150 degrees Celsius. This allowed us to increase the number of charge cycles by almost three times compared to conventional lithium-oxygen variants. Also, scientists have been able to increase the energy content per unit mass by more than 50%.
“This discovery underscores the tremendous opportunity to create new battery technologies that can potentially challenge lithium-ion batteries and other storage methods,” the scientists write.