초록
The Li-air battery is a promising candidate for the most energy-dense electrochemical power source because it has 5 to 10 times greater energy storage capacity than that of Li-ion batteries. However, the Li-air cell performance falls short of the theoretical estimate, primarily because the discharge terminates well before the pore volume of the air electrode is completely filled with lithium oxides. Therefore, the structure of carbon used in the air electrode is a critical factor that affects the performance of Li-air batteries. In a previous study, we reported a new class of carbon nanomaterial, named carbon nanoballs (CNBs), consisting of highly mesoporous spheres. Structural characterization revealed that the synthesized CNBs have excellent a meso-macro hierarchical pore structure, with an average diameter greater than 10 nm and a total pore volume more than $1.00cm^3g^{-1}$. In this study, CNBs are applied in an actual Li-air battery to evaluate the electrochemical performance. The formation mechanism and electrochemical performance of the CNBs are discussed in detail.