Role of high temperature quenching in structure and performance of Mn-based layered cathode materials for sodium-ion batteries
Mn-based layered cathodes are a prominent class of cathode materials for sodium-ion batteries,characterized by high theoretical specific capacity,low cost,and high thermal stability.However,these materials are prone to structural distortions,Na+/vacancy ordering,and the formation of transition metal vacancies,which detrimentally affect cyclic stability.Previous research indicates that mitigating transition metal vacancies can effectively enhance the electrochemical performance of these cathodes.This study investigates the impact of high-temperature liquid nitrogen quenching on the structure and performance of Na0.67Fe1/3Co1/3Mn1/3 O2(NFCMO)and its quenched counterpart—NFCMO-LN—during the sol-gel process.NFCMO-LN exhibits improved specific capacity and rate capability compared with pristine NFCMO.Specifically,NFCMO and NFCMO-LN demonstrate initial cycle discharge capacities of 91.1 mAh/g and 129.8 mAh/g at 0.1C,respectively.Furthermore,after 100 cycles at 1C,NFCMO retains 100%of its capacity,whereas NFCMO-LN maintains 90%.Remarkably,NFCMO-LN achieves a discharge capacity of 56.2 mAh/g at a high rate of 10C.Structural analyses reveal that liquid nitrogen quenching effectively reduces transition metal vacancies and enhances structural stability,offering viable strategies for the design and optimization of cathode materials in sodium-ion batteries.
sodium ion batterylayered oxidesodium manganatelattice dopingquenching
国家科技期刊平台
NSTL
万方数据
