钴-碳框架封装作为固态电解质层实现稳定的氧化硅负极用于锂存储
Cobalt-carbon framework encapsulation as solid electrolyte interphase ensures stable SiOx anodes for lithium storage
陈本强 1许东明 1周双 1常智 1潘安强2
作者信息
- 1. School of Materials Science and Engineering,Key Laboratory of Electronic Packaging and Advanced Functional Materials of Hunan Province,Central South University,Changsha 410083,China
- 2. School of Materials Science and Engineering,Key Laboratory of Electronic Packaging and Advanced Functional Materials of Hunan Province,Central South University,Changsha 410083,China;School of Materials Science and Engineering,Xinjiang Environmental and Functional Materials Engineering Research Center,Xinjiang University,Urumqi 830046,China
- 折叠
摘要
非化学计量的氧化硅(SiOx,0＜x＜2)是一种很有前途的锂电池负极材料.然而,它的本征电导率低,体积膨胀明显.特别是,由于连续的电解液消耗,很难形成稳定的固体电解质界面.本工作将空心氧化硅微球包裹在钴碳(Co-C)骨架及其衍生的氮掺杂碳纳米管网络(N-CNTs)中.这种设计解决了电解液消耗和SEI层重复形成的问题,并实现了快速动力学.此外,所制备材料的柔性碳纳米管和坚固金属-碳框架提供力学支撑,可以适应SiOx体积变化.h-SiO,@Co@N-CNTs作为锂离子电池负极材料,具有优异的循环稳定性和高倍率性能.以0.2 A g-1的电流密度循环370次,容量为701 mAh g-1,容量保持率为100％.另外,在1.0 A g-1电流密度下循环500圈,容量没有衰减.结果表明,所合成的锂离子电池结构具有一定的优越性,对材料的优化也有一定的启发作用.
Abstract
Non-stoichiometric silicon oxide(SiOx,0＜x＜2)is a promising anode material for lithium batteries.However,it suffers from low intrinsic conductivity and large volume expansion.In particular,reaching a stable solid electrolyte interphase(SEI)is difficult due to continuous electrolyte consumption.In this work,hollow silicon oxide(h-SiOx)spheres were encapsulated in cobalt-carbon(Co-C)frame-works and their derived nitrogen-doped carbon nanotube networks(N-CNTs).This design solved the problems of elec-trolyte depletion and repetitive formation of SEI layers and enabled fast kinetics.In addition,the flexible carbon nano-tubes and metal-carbon solid frameworks of the prepared materials provide mechanical supports,which can adapt to the volume change of SiOx.The h-SiOx@Co@N-CNTs exhibit su-perior cycling stability and high-rate capability as anode ma-terials for lithium-ion batteries.It delivered a capacity of 701 mAh g-1 and a capacity retention of 100％over 370 cycles at a current density of 0.2 A g-1.In addition,the capacity did not fade after 500 cycles at a current density of 1.0 A g-1.The result demonstrates the advantage of the synthesized structure for lithium-ion batteries,which can also give some inspiration for this material optimization.
关键词
lithium-ion battery/SiOx anode/SEI/metal-organic framework/volume changesKey words
lithium-ion battery/SiOx anode/SEI/metal-organic framework/volume changes引用本文复制引用
基金项目
National Natural Science Foundation of China(51874362)
National Natural Science Foundation of China(22209208)
Key Research and Development Program of Hunan Province(2023GK2015)
Science and Technology Innovation Leader Program of Hunan Province(2022RC3049)
出版年
2024
NETL
NSTL
万方数据