08 IN FOCUS In the News Rechargeable battery breakthrough Hearing aids, flashlights, remote control devices, and other household items could become more sustainable in the future, thanks to a novel electrode design by School of Engineering researchers that enables the alkaline zinc batteries these devices use to become rechargeable. The team, led by Prof. CHEN Qing, Mechanical & Aerospace Engineering and Chemistry, has developed a nanoporous zinc metal electrode capable of stabilizing the electrochemical transition between zinc and zinc oxide, successfully turning an alkaline zinc-air coin cell into a rechargeable battery stable for over hours. To do this, the team shaped zinc into curvy laments hundreds of nanometers wide, nested in a freestanding solid with numerous, similarly narrow pores. When the battery is discharged, a thin layer of zinc oxide nucleates on the zinc laments, preserving the metallic network and enabling the zinc electrode to return to its initial structure. In addition, the team has tested the new electrode in alkaline nickel-zinc batteries. Results showed an increase from the normal lifespan of to discharges and charges to more than , under conditions competitive with state-of-the-art lithium-ion batteries. Prof. Chen pointed out that alkaline zinc batteries had an edge over other batteries due to their safety, low cost and energy density. In industry, they are ideal for golf carts and forkli trucks, among others. They are also suitable for emerging applications, for example, back-up power for data centers, which do not need multiple discharging and charging but require the battery to be extremely safe. The research has been published in Nature Communications. Prof. Chen’s group has also been working with industrial partners since the research started in to assist development and commercialization of the battery technology. Key step forward for renewable energy An international research team led by Prof. Francesco CIUCCI, Mechanical and Aerospace Engineering, has designed an iron-based cathode material that achieves record performance for protonic ceramic fuel cells (PCFCs), marking a signi cant step forward in the commercialization of this renewable energy technology. PCFCs are generally used for distributed power generation and have the advantages of low pollutant emissions, high e ciency, and the flexibility of working well with hydrogen and other gases, including ammonia and biogas. However, a lack of high-performance and low-cost cathode materials have hindered development to date. By combining rst-principle simulations, molecular orbital analysis, and experiments, Prof. Ciucci’s team has now designed ceramics using inexpensive elements such as barium, iron, and zirconium, leading to a PCFC with record performance. The research has been published in Nature Catalysis and highlighted in Nature Reviews Materials. Team members include collaborators from Mainland China, South Korea, and Australia. A 3D model of the zinc electrode’s nanoporous structure, magni ed 10,000 times. Prof. Francesco Ciucci’s iron-based cathode material has enabled protonic ceramic fuel cells to attain record performance.