Structural self-reconstruction strategy empowering Ni-rich layered cathodes with low-strain for superior cyclabilities  

作　　者：Zhouliang Tan Yunjiao Li Xiaoming Xi Shijie Jiang Xiaohui Li Xingjie Shen Panpan Zhang Zhenjiang He 

机构地区：[1]School of Metallurgy and Environment,Central South University,Changsha 410083,China [2]Engineering Research Center of the Ministry of Education for Advanced Battery Materials,Central South University,Changsha 410083,China [3]Changsha Research Institute of Mining and Metallurgy,Changsha 410083,China [4]Office of Laboratory and Equipment Management,Xinjiang University,Urumqi 830000,China

出　　处：《Nano Research》2023年第4期4950-4960,共11页纳米研究（英文版）

基　　金：supported by the Science and Technology of Guangxi Zhuang Autonomous Region(Gangxi Special Fund for Scientific Center and Talent Resources,Nos.FA2020011 and FA20210713).

摘　　要：The key to hindering the commercial application of Ni-rich layered cathode is its severe structural and interface degradation during the undesired phase transition(hexagonal to hexagonal(H2→H3)),degenerating from the build-up of mechanical strain and undesired parasitic reactions.Herein,a perovskite Li_(0.35)La_(0.55)TiO_(3)(LLTO)layer is built onto Ni-rich cathodes crystal to induce layered@spinel@perovskite heterostructure to solve the root cause of capacity fade.Intensive exploration based on structure characterizations,in situ X-ray diffraction techniques,and first-principles calculations demonstrate that such a unique heterostructure not only can improve the ability of the host structure to withstand the mechanical strain but also provides fast diffusion channels for lithium ions as well as provides a protective barrier against electrolyte corrosion.Impressively,the LLTO modified LiNi_(0.9)Co_(0.05)Mn_(0.05)O_(2)cathode manifests an unexpected cyclability with an extremely high-capacity retention of≈94.6%after 100 cycles,which is superior to the pristine LiNi_(0.9)Co_(0.05)Mn_(0.05)O_(2)(79.8%).Furthermore,this modified electrode also shows significantly enhanced cycling stability even withstanding a high cut-off voltage of 4.6 V.This surface self-reconstruction strategy provides deep insight into the structure/interface engineering to synergistically stabilize structure stability and regulate the physicochemical properties of Ni-rich cathodes,which will also unlock a new perspective of surface interface engineering for layered cathode materials.

关 键 词：Ni-rich layered oxides cathode structural self-reconstruction phase transition mechanical strain first-principal calculation 

分 类 号：TM912[电气工程—电力电子与电力传动] TQ131.11[化学工程—无机化工]