摘要
锂离子电池作为一种绿色环保的储能器件,在许多领域得到了广泛应用,如手机、笔记本、摄像机、医疗器械等便携式电子器件以及新能源电动汽车等。特别地,随着社会的进步、人类的发展,能源枯竭、石油危机、汽车尾气排放等问题日趋严峻,新能源动力汽车异军突起,而锂离子电池作为动力电池的最优选择,其能量密度的提升对推动新能源动力汽车领域的发展具有重大意义。锂离子电池电极材料是限制其能量密度的关键因素。目前,锂离子电池所采用的负极材料为石墨,其理论比容量仅为372 m Ah/g。在众多新型负极材料中,硅材料因具有4200 m Ah/g的超高理论比容量而备受研究者瞩目,但是硅材料自身存在导电率低、体积膨胀大、结构不稳定等问题,导致其电化学性能不佳。研究者们主要通过将硅材料纳米化来提高其结构稳定性及循环稳定性。当前,纳米硅材料的制备方法主要有化学气相沉积法、等离子蒸发冷凝法及机械球磨法,但是普遍存在对设备要求条件苛刻、制备成本高、流程复杂等问题。实现纳米硅的短流程、低成本制备,对于推动硅基负极,特别是硅碳复合负极的商业化应用具有重要意义。本文重点综述了基于金属热还原特别是镁热还原法制备的纳米硅在锂离子电池中的研究进展,分析了采用金属热还原制备纳米硅的技术优势,总结了近年来镁热还原制备的纳米硅基负极材料的性能,展望了金属热还原技术低成本制备纳米硅材料的发展前景。
As a kind of green and environmental-friendly energy storage,lithium ion batteries(LIBs)are received widely used in many fields,such as mobile phone,laptop,camera,medical instrument and other portable electronic devices,even in new energy electric vehicle.Especially,with the progress of society and the development of human beings,depletion of energy resources,oil crisis and motor vehicle exhaust problems are increasingly serious day by day.The dramatic rise of new energy powered cars asserts requirement of LIBs,which is regarded as one of the most suitable energy devices.And the improvement of energy density of LIBs will be of great significance to the development of new energy powered cars.The electrode materials are typical factors that limit the energy density of LIBs.Currently,the commercialized anode for LIBs are graphite,which have a very limited theoretical capacity of 372 m Ah/g.Among various new type promising anodes,silicon has reached considerable attention due to its ultrahigh theoretical capacity of 4200 m Ah/g.However,the low electronic conductivity,large volume expansion and unstable structure lead to the poor electrochemical performance of silicon anodes.It is demonstrated that the utilization of nano silicon is one of an efficient way to increase the structural stability and cycling performance.At present,the fabrication of nano silicon mainly includes chemical vapor deposition,plasma evaporation and condensation method and mechanical ball milling method.However,the above strategies always refer to demanding conditions for equipment,high cost and multi-steps.Therefore,the fabrication of nano silicon with short process and low cost will be of great importance to promote the application of silicon based anode especially silicon/carbon anode for LIBs.In this review,we focus on the recent progress of fabricating nano silicon by metallothermic reduction reactions especially by magnesiothermic reduction and the applications in LIBs.The technological advantages of metallothermic reduction reactions are
作者
玉日泉
YU Riquan(CINF Engineering Co.,Ltd.,Changsha 410083,China)
出处
《材料导报》
EI
CAS
CSCD
北大核心
2021年第3期3041-3049,共9页
Materials Reports
关键词
金属热还原
镁热还原
纳米硅
负极
锂离子电池
metallothermic reduction
magnesiothermic reduction
nano silicon
anode
lithium ion batteries
