物理学报2024，Vol.73Issue(2)：302-309,8.DOI:10.7498/aps.73.20231361
通过Mo掺杂诱导低Li/Ni混排程度增强Li1.2Ni0.13Fe0.13Mn0.54O2 可逆容量与循环稳定性
Enhancing reversible capacity and cycling stability of Li1.2Ni0.13Fe0.13Mn0.54O2 by inducing low Li/Ni misalignment through Mo doping
摘要
Abstract
Li-ion batteries(LIBs)are widely used in mobile devices and electric vehicles,but the traditional layered transition metal cathode material,LiTMO2(TM=Ni,Co,Mn,or Al),has a low energy density that cannot satisfy the demand of commercial applications.The Li-rich Mn-based layered oxides(LRLOs)are a strong competitor to the traditional layered cathode materials for their specific capacity of more than 200 mAh/g.Due to the high energy density and low cost,Li-rich Mn-based layered oxides(LRLO)have been a promising candidate cathode for next-generation Li-ion batteries.The anionic redox reaction(ARR)in LRLO destabilizes the lattice oxygen,leading to voltage degradation and capacity loss.Although iron-substituted cobalt-free Li-rich materials can achieve less voltage decay,they suffer severe cation disorder and poor kinetics.Here,we develop a simple and feasible high-valent ion doping strategy by doping Mo into Li1.2Ni0.13Fe0.13Mn0.54O2(LNFMO),which expands the Li layer spacing and provides a broader channel for Li+ transport,thereby improving the diffusion kinetics of Li+,effectively suppressing the cation disorder,and further stabilizing the layered structure.As a result,the Mo-doped LRLO exhibits significantly enhanced electrochemical performance,with an initial reversible capacity of 209.48 mAh/g at 0.2 C,and the initial specific capacity increasing from 137.02 mAh/g to 165.15 mAh/g at 1 C.After 300 cycles,specific capacity remains 117.49 mAh/g for the Mo-doped cathode,and the voltage decay decreases from 2.09 mV/cycle to 1.66 mV/cycle.The Mo-doped LRLO is systematically characterized,and the mechanism of cycle stabilization is revealed,which provides an important reference for designing high performance Li-rich cathode.关键词
锂离子电池/富锂层状氧化物/正极材料/阳离子混排Key words
Li-ion batteries/Li-rich layered oxides/cathode materials/cationic disorder引用本文复制引用
冉沛林,吴康,赵恩岳,王芳卫,毋志民..通过Mo掺杂诱导低Li/Ni混排程度增强Li1.2Ni0.13Fe0.13Mn0.54O2 可逆容量与循环稳定性[J].物理学报,2024,73(2):302-309,8.基金项目
重庆市教委科学技术研究计划重点项目(批准号:KJZD-K202300512)和国家自然科学基金(批准号:52088101,12105197)资助的课题. Project supported by the Key Project of Scientific and Technological Research Program of Chongqing Municipal Education Commission of China(Grant No.KJZD-K202300512)and the National Natural Science Foundation of China(Grant Nos.52088101,12105197). （批准号:KJZD-K202300512）
