This week, the National Institute for Materials Science announced that its lithium-air batteries developed using “original materials” had an energy density of over 500 Wh/kg. This is the measure of how much energy a battery has in relation to its weight.
Research groups around the world are focusing on the demand for more energy-efficient batteries while keeping them lighter than the current models. This is especially important for electric planes and cars. 500 Wh/kg is a good benchmark in pursuit of this goal. However, the current best-in-class lithium-ion battery technology has energy densities between 250 and 300Wh/kg. Lithium-air batteries are a promising choice of chemistries because they offer big energy density gains, high capacity, and are lightweight.
NIMS has been developing lithium-air batteries in collaboration with the Japanese government-funded ALCA-SPRING program. The program wants to achieve battery R&D which facilities the large-scale production of the cells. Softbank and NIMS co-founded the Advanced Technologies Development Center in 2018. The center aims to put lithium-air batteries to practical use in mobile phones base stations and other technologies. They have since combined new materials that significantly increase the performance of lithium-air batteries, developed as part of the ALCA-SPRING-supported research, with a technique to fabricate high-energy-density lithium-air cells at the Advanced Technologies Development Center.
According to NIMS’s own tests, the resulting lithium-ion battery had an energy density exceeding 500 Wh/kg. The repeated discharge and charge reaction occurred at room temperature.
“The energy density and cycle life performance of this lithium-ion battery are amongst their highest ever achieved,” a report published by NIMS.
According to the team, it is currently working on developing higher-performance batteries materials. They plan to incorporate them into the lithium-air to increase the battery’s cycle life. The team plans to accelerate efforts to make the battery practical at the NIMS SoftBank Advanced Technologies Development Center.