Ultrafast synthesis of cation/anion co-doped Li-rich layered oxide cathodes with Li+/Ni2+ mixing structural defects†
Abstract
Li-rich layered oxide (LLO) cathodes hold great promise for high-energy lithium-ion batteries, but suffer from rapid voltage and capacity degradation, and inferior rate capability. Besides, traditional synthesis approaches require long-time heat treatment (typically several hours) due to the sluggish kinetics, leading to high energy consumption and cost. Here, we introduce an innovative approach to address these challenges through ultrafast synthesis of cation/anion co-doped LLO with structural defects. By utilizing a rapid synthesis technique of nickel foil-based thermal shock, simultaneous doping of cation and anion species into the LLO structure with Li+/Ni2+ mixing defects is achieved in seconds. The ultrafast synthesis remarkably reduces the cost and energy consumption. Furthermore, this cation/anion co-doping and Li+/Ni2+ mixing defects significantly enhance lithium-ion transport and suppress the irreversible oxygen release and structural transformation, and demonstrate enhanced cycling stability with minimal voltage degradation over extended charge–discharge cycles and improved rate capability. Our findings offer a promising avenue to unlock the full potential and an effective synthesis approach of Li-rich layered oxide cathodes for advanced lithium-ion batteries.