The energy density of lithium-air batteries is expected to hit a new high, and it remains stable after thousands of charge-discharge cycles

Science and Technology Daily reporter Liu Xia

According to the latest issue of “Science” magazine, researchers from the Argonne National Laboratory of the U.S. Department of Energy and the Illinois Institute of Technology have jointly developed a new type of lithium-air battery, which uses a solid electrolyte, which is not only safe, but also survives 1,000 charge-discharge cycles. keep it steady. Further research is expected to make its energy density four times that of lithium-ion batteries, which can not only provide longer cruising range for electric vehicles, but also provide electricity for aircraft and long-distance trucks.

The research team explained that the main new component of the new lithium-air battery is a solid electrolyte, rather than the commonly used liquid electrolyte, which can catch fire due to overheating.

In addition, during the discharge process of lithium-air batteries in the past, the lithium in the metal anode will pass through the liquid electrolyte and combine with oxygen to produce lithium peroxide or lithium superoxide at the cathode. During charging, lithium peroxide or lithium superoxide is decomposed into lithium and oxygen. The solid electrolyte in the newly developed battery consists of a ceramic polymer, a polymer material made of relatively cheap elements in the form of nanoparticles that produces lithium oxide when discharged.

The Argonne researchers say the chemical reaction that produces lithium superoxide, or lithium peroxide, involves only one or two electrons stored per oxygen molecule. The chemical reaction that produces lithium oxide involves four electrons, and more electrons stored mean higher energy density. The newly developed lithium-air battery is the first lithium-air battery to achieve 4 electron reactions at room temperature.

The energy density of lithium-air batteries is expected to hit a new high, and it remains stable after thousands of charge-discharge cycles

The research team pointed out that the previous lithium-air battery had a very short cycle life, while the new product remained stable after 1,000 charge-discharge cycles. In addition, with further development, the new lithium-air battery will have a record energy density of 1200 Wh/kg, almost four times that of lithium-ion batteries.