Lithium-air batteries

New technology lithium-air batteries make them closer to practical application

Lithium-air batteries

Having densities of energy storage, comparable to the energy performance of the liquid fuel, lithium-air (lithium-oxygen) batteries can be a solution that allows owners of electric cars don't worry much about the limits of trip distance on one battery charge. But until now scientists still have to solve a lot of problems, one of which is a layer of lithium peroxide, growing on the electrode surface, which blocks the flow of oxygen, resulting in decreased battery capacity. And finally, scientists have found a method that allows you to avoid this undesirable phenomenon, and this, in turn, will increase the capacity of batteries by five times compared to existing lithium-air and lithium-ion batteries.

The above-mentioned lithium peroxide is a by-product of the electrochemical reactions occurring inside the battery. One way to avoid the formation of a layer of this compound is to change the composition of the electrode material and the composition of the electrolyte so that as a by-product of the reaction began to form soluble lithium hydroxide. This technology was developed at the end of last year researchers from Cambridge University.

But the method developed by Cambridge scientists, is quite complicated, and scientists from the National laboratory, Argonne (Argonne National Laboratory) decided to simplify it by focusing on changing only the material of the battery electrode. The research on new electrode material, the surface of which is peroxide began to form lithium hydroxide, which can be easily split into its component parts, lithium, oxygen and hydrogen. The breakdown of superoxide to hydroxide and then to composite components will even allow you to create a closed system Li-air battery, which will not require income oxygen from the environment, which will make these batteries more safe, reliable and efficient.

"Stabilization of the superoxide phase lithium may lead to the development of closed battery cells, whose capacity will be five times the capacity of traditional lithium-ion batteries of comparable size," says Amin Khalil (Khalil Amine), a member of the research team.

The formation of lithium superoxide is produced due to the presence of iridium nanoparticles on the electrode surface. Under normal conditions this compound is difficult to synthesis because of its thermodynamic instability. However, atoms of iridium in this case act as a highly efficient catalyst and stabilizer of the reaction.

"Our discovery opens the way for the development of a battery of principle of a new type," says Larry Curtiss (Larry Curtiss), a scientist from the laboratory of the Argonne, "But we still have to do a lot of work on improving the processes in such batteries, which should dramatically increase the duration of their life cycle".