Researchers at Graphene Flagship partners Trinity College Dublin, Ireland, CIC EnergiGUNE and INCAR-CSIC, Spain, have produced rechargeable batteries and energy storage devices made of a non-toxic and environmentally friendly graphene-based material.  With current metal-ion batteries reaching their theoretical limitations in terms of cycle life, capacity and power, researchers focused on metal-air alternatives, such as sodium-air (Na-O2) batteries. Equipped with sodium anodes and oxygen-trappi...