文献类型：期刊文献

中文题名：硼高效掺杂LiNi0.5Co0.2Mn0.3O2正极材料及其性能提升机制

英文题名：Synthesis and performance improvement mechanism of high-efficiency Bdoped LiNi0.5Co0.2Mn0.3O2 cathode materials for Li-ion batteries

作者：朱华威[1];余海峰[1];江仟仟[1];杨兆峰[1];江浩[1];李春忠[1]

机构：[1]华东理工大学超细材料制备与应用教育部重点实验室,上海200237

年份：2021

卷号：72

期号：1

起止页码：609

中文期刊名：化工学报

外文期刊名：CIESC Journal

收录：CSTPCD;;EI(收录号：20210509871530);Scopus;北大核心:【北大核心2020】；CSCD:【CSCD2021_2022】；

基金：国家自然科学基金项目(21975074,91834301)。

语种：中文

中文关键词：LiNi0.5Co0.2Mn0.3O2;高电压;硼掺杂;锂离子电池

外文关键词：LiNi0.5Co0.2Mn0.3O2;high voltage;B doping;Li-ion batteries

摘要：高键能异质原子的高效掺杂是稳定高电压LiNi0.5Co0.2Mn0.3O2(NCM)三元正极材料并提升其电化学性能的有效策略。借助含硼前体在二次颗粒表面富集及随后高温煅烧强化B3+体相扩散的策略,构建了硼离子高效掺杂NCM正极材料(NCM-B)。引入B—O键(键能:809 kJ·mol^?1)抑制了电化学反应过程中晶格氧析出,进而稳定材料的氧离子框架;此外,表面残余的高锂离子导体Li2O-B2O3包覆层可以在一定程度上稳定电极-电解液界面。与改性前NCM相比,改性后的NCM-B正极材料在3.0~4.5 V电压区间的可逆比电容量可以达到193.7 mA·h·g^?1,在10 C大功率下,比电容量仍保持120 mA·h·g^?1(NCM仅为78.2 mA·h·g^?1)。1 C下连续循环100圈后,比电容量保持率从73%提升到90%。表面富集和扩散强化的思想也有望实现其他正极材料的高效掺杂。
High-efficiency doping of strong-bonding energy heteroatoms is an effective strategy to stabilize highvoltage LiNi0.5Co0.2Mn0.3O2(NCM)ternary cathode materials and improve their electrochemical performance.Herein,a strategy with boron-containing precursor surface enrichment and diffusion-reinforcement by high-temperature calcination is proposed to construct high-efficiency B-doped LiNi0.5Co0.2Mn0.3O2 cathode material(NCM-B).The high B—O bond energy(809 kJ·mol^?1)greatly inhibits the evolution of oxygen atoms,hence steadying the oxygen ion framework.Moreover,the LiO2-B2O3 coating layer with high Li+conductivity can stabilize the electrodeelectrolyte interface.Compared with pure NCM,the NCM-B exhibits a high reversible capacity of 193.7 mA·h·g^?1 within 3.0—4.5 V and delivers a superior high-rate performance of 120 mA·h·g^?1 at 10 C(only 78.2 mA·h·g^?1 for NCM).Furthermore,the capacity retention after 100 cycles at 1 C can be improved from 73%to 90%.The present surface-enrichment and diffusion-reinforcement strategy is expected to realize high-efficiency doping of other cathode materials.