Advanced intercalation cathodes for lithium-ion batteries: Challenges, strategies, and next successors
摘要
Since the invention of intercalation cathodes, the development of Li-ion battery has evolved significantly in the last millennium. 2-dimensional layered LMO2 of LiCoO2 demonstrates outstanding results in working voltage, capacity, and energy density, but there are still concerns regarding sustainability of its core element cobalt, conductivity, thermal sensitivity, and stability. Next generation intercalation cathode of 3-dimensional spinel LM2O4 shows excellence in working voltage and conductivity, but it bears the issue with low capacity and high thermal sensitivity. Jhan-Teller distortion occurs when its core element Mn for LiMn2O4 have different electronic configurations. Last generation cathode of olivine LiMXO4 by LiFePO4 shows superiority in stability and thermal sensitivity due to its 1-dimensional sites of Li-ion in FePO4 layers but it still has consequences for low capacity and low conductivity. Several strategies were established to overcome issues according to mechanism related with intercalation cathodes: (1) surface modification, (2) defect structure, (3) composite structure, (4) ternary layered configuration, and (5) lithium excess enhancement by lithium rich layered oxide (LLO). Finally, this paper also discusses upcoming conversion-based cathodes to succeed limitations of intercalation cathodes.