Facile preparation of core-shell Si@Li4Ti5O12 nanocomposite as large-capacity lithium-ion battery anode

• 来源期刊: 能源化学
• 年，卷（期）: 2020,（1）
• 页码范围: 89-98
• 页数: 10页
• 语种: 英文

摘要

As a promising alternative anode material,silicon (Si) presents a larger capacity than the commercial anode to achieve large capacity lithium-ion batteries.However,the application of pure Si as anode is hampered by limitations such as volume expansion,low conductivity and unstable solid electrolyte interphase.To break through these limitations,the core-shell Si@Li4Ti5O12 nanocomposite,which was prepared via in-situ self-assembly reaction and decompressive boiling fast concentration method,was proposed in this work.This anode combines the advantages of nano-sized Si particle and pure Li4Ti5O12 (LTO) coating layer,improving the performance of the lithium-ion batteries.The Si@Li4Ti5O12 anode displays a high initial discharge/charge specific capacity of 1756/1383 mAh g-1 at 500 mAg-1 (representing high initial coulombic efficiency of 78.8％),a large rate capability (specific capacity of 620mAhg-1 at 4000 mAg-1),an outstanding cycling stability (reversible specific capacity of 883 mAhg-1 after 150 cycles) and a low volume expansion rate (only 3.3％ after 150 cycles).Moreover,the synthesis process shows the merits of efficiency,simplicity,and economy,providing a reliable method to fabricate large capacity Si@Li4Ti5O12 nanocomposite anode materials for practical lithium-ion batteries.