Development of air electrode materials in lithium-oxygen batteries for improving next-generation electric vehicles

Abstract

With increasing needs for large-scale energy storage technologies, rechargeable lithium-air (Li-O2) battery has been recognized as one of the most promising candidates over the past decade. The Li-air batteries have the highest theoretical energy density $(3,505 Wh kg^{-1})$ among any known energy storage systems, but the critical challenges including high charging overpotential, low power density, and low round-trip efficiency resulting in poor cycle life still remain unsolved. Especially, the development of efficient air cathode has a great significance for improving overall cell performance because the key reactions, i.e., oxygen reduction and evolution reaction (ORR/OER), occur at the cathode surface during battery operation. In this thesis, we introduce various 1D nanomaterials as catalysts in air cathode, and assess the cell performance. Furthermore, we suggest a new air cathode configuration, in which 1D carbon nanofibers (CNFs) network as a current collector is integrated with catalysts, and assess its electrochemical performance in $Li-O-2$ battery and feasibility in real Li-air battery.