A Safe and Sustainable Lithium‐Ion–Oxygen Battery based on a Low‐Cost Dual‐Carbon Electrodes Architecture

Abstract People anticipate high‐energy‐density battery technology with better security, stability, and sustainability. By tuning the advantage of specific capacity, the lithium‐metal anode is replaced with a graphite intercalation compound and a conceptual prototype lithium‐ion–oxygen battery based on a low‐cost dual‐carbon electrodes architecture is proposed. The lithium‐ion involves a (de)intercalation process into the graphite anode and an O 2 /Li 2 O 2 redox conversion on the carbon‐nanotube cathode. After a thorough examination as to the electrode compatibility with current electrolytes, a nonflammable fluorinated ether electrolyte is proposed to render a highly coordinated solvation sheath and low lithium salt concentration (1 mol). Herein, the compatibility with graphite anode is investigated, which maintains high capacity retention (88.1%) after long‐term lifespan (over 1 year). In view of the ultrahigh reversibility (average Coulombic efficiency over 99.93%) of the graphite anode, a lithium‐ion–oxygen coin cell with high depth‐of‐discharge of 80% and 60% deliver a satisfactory life over 150 and 300 cycles, respectively. Moreover, systematic spectroscopy characterizations demonstrate a reversible and efficient 2e – O 2 /Li 2 O 2 redox reaction without relying on noble‐metal catalysts. Lastly, in the engineering aspect, a high‐energy‐density pouch cell (302.52 W h kg −1 based on the weight of the entire pouch) with cost‐effective and environmentally friendly carbon‐composed cell components is successfully fabricated.