Tailoring deposition and morphology of discharge products towards high-rate and long-life lithium-oxygen batteries.

Lithium-oxygen batteries are an attractive technology for electrical energy storage because of their exceptionally high-energy density; however, battery applications still suffer from low rate capability, poor cycle stability and a shortage of stable electrolytes. Here we report design and synthesis of a free-standing honeycomb-like palladium-modified hollow spherical carbon deposited onto carbon paper, as a cathode for a lithium-oxygen battery. The battery is capable of operation with high-rate (5,900 mAh g ⁻¹ at a current density of 1.5 A g⁻¹) and long-term (100 cycles at a current density of 300 mA g⁻¹ and a specific capacity limit of 1,000 mAh g⁻¹). These properties are explained by the tailored deposition and morphology of the discharge products as well as the alleviated electrolyte decomposition compared with the conventional carbon cathodes. The encouraging performance also offers hope to design more advanced cathode architectures for lithium-oxygen batteries.