Double-shell Li-rich layered oxide hollow microspheres with sandwich-like carbon@spinel@layered@spinel@carbon shells as high-rate lithium ion battery cathode
Double-shell Li-rich layered oxide hollow microspheres with sandwich-like carbon@spinel@layered@spinel@carbon shells as high-rate lithium ion battery cathode
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具有三明治状碳@尖晶石@层状@尖晶石@碳壳的双壳富锂层状氧化物空心微球作为高倍率锂离子电池正极
DOI：
10.1016/j.nanoen.2019.02.040
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发表时间：
2019-05-01
期刊：
影响因子：
17.6
通讯作者：
Peng, Dong-Liang
中科院分区：
文献类型：
--
作者：
Ma, Yating;Liu, Pengfei;Peng, Dong-Liang
富锂层状氧化物（LRLO）具有超过250 mAh g（-1）的高比容量，是下一代高性能锂离子电池的理想正极材料。然而，LRLO总是遭受低的初始库仑效率，差的循环和倍率性能。本文采用无模板法，通过碳热还原反应，成功合成了独特的双层LRLO中空微球（LRLO-500@S@C）。制备的LRLO-500@S@C阴极提供312.5mAh g（-1）的高初始充电容量和89.7%的大初始库仑效率。循环200次后，在1.0C和5.0C下分别获得了228.3mAhg（-1）和196.1mAhg（-1）的大而稳定的放电容量。此外，以LRLO-500@S@C为阴极，Li（4）Ti（5）O（12）为阳极的纽扣型全电池具有出色的锂存储性能。LRLO-500@S@C正极材料之所以具有优异的电化学性能，是因为其基于分层双壳层中空结构的多尺度协同设计、特殊的层状@尖晶石@碳异质结构壳层以及引入的氧空位，有利于缩短锂离子扩散路径，增强结构稳定性，减少副反应。
Li-rich layered oxides (LRLO) with high specific capacity over 250 mA h g(-1) are attractive cathode material candidates for the next-generation high performance lithium-ion batteries. However, LRLO always suffers from low initial Coulombic efficiency, poor cycling and rate properties. Herein, unique double-shell LRLO hollow microspheres with sandwich-like carbon@spinel@layered@spinel@carbon shells (LRLO-500@S@C) were successfully synthesized via a facile template-free method, followed by carbothermal reduction treatment. The fabricated LRLO-500@S@C cathode delivers a high initial charge capacity of 312.5 mA h g(-1 )with a large initial Coulombic efficiency of 89.7%. After cycling 200 times, large and stable discharge capacities of 228.3 mA h g(-1) and 196.1 mA h g(-1) can be obtained at 1.0 C and 5.0 C, respectively. Moreover, coin-type full cell with LRLO-500@S@C as cathode and Li(4)Ti(5)O(12 )as anode delivers outstanding lithium storage properties. The impressive electrochemical performances of LRLO-500@S@C cathode material can be attributed to its multiscale co-ordinated design based on hierarchical double-shell hollow construction, the special layered@spinel@carbon heterostructured shells and the introduced oxygen vacancies, which benefit to shorten Li-ion diffusion paths, strengthen structural stability and reduce side reactions.