熔浸-液相硫化法制备高容量硫化锂/石墨复合正极材料  

Preparation of high capacity lithium sulfide/graphite composite cathode material by immersion-liquid phase vulcanization method

作　　者：施洪勇 杨佳 夏立新 潘顺伟 崔兆丰 谈仁杰 谈宏磊 SHI Hongyong;YANG Jia;XIA Lixin;PAN Shunwei;CUI Zhaofeng;TAN Renjie;TAN Honglei(State Key Laboratory of Complex Non-ferrous Metal Resources Clean Utilization,Kunming University of Science and Technology,Kunming 650093,China;National Engineering Research Center for Vacuum Metallurgy,Kunming University of Science and Technology,Kunming 650093,China;Faculty of Metallurgical and Energy Engineering,Kunming University of Science and Technology,Kunming 650093,China;Key Laboratory for Nonferrous Vacuum Metallurgy of Yunnan Province,Kunming University of Science and Technology,Kunming 650093,China)

机构地区：[1]昆明理工大学复杂有色金属资源清洁利用国家重点实验室,云南昆明650093 [2]昆明理工大学真空冶金国家工程研究中心,云南昆明650093 [3]昆明理工大学冶金与能源工程学院,云南昆明650093 [4]昆明理工大学云南省有色真空冶金重点实验室,云南昆明650093

出　　处：《中国有色冶金》2025年第1期85-95,共11页China Nonferrous Metallurgy

基　　金：国家自然科学基金项目(52104350、52264038);国家重点研发计划(2022YFC2904204);云南省自然科学基金项目(202001AT070045);昆明理工大学分析测试中心项目(2022M20212202120)。

摘　　要：硫化锂复合石墨材料的制备是许多学者关注的热点,而如何制备高容量的硫化锂复合石墨结构材料则更具有研究意义,目前采用石墨热还原硫酸锂方法进行工业规模生产此材料,该过程需要高温体系,并且属于固相反应,反应速率以及粒径均受限于硫酸锂。本文提出在真空体系下利用高温使锂熔浸浸入廉价石墨层内部,并在同体系下进行硫化制得硫化锂/石墨复合正极材料的思路。研究进行了熔浸-液相硫化试验,并考察了各参数对所制备材料的锂挥发率和锂填充率的影响,得到以下主要结论:最佳熔浸工艺参数为熔浸温度1173 K、时间180 min,最佳硫化工艺参数为硫化温度453 K、时间40 min,该反应过程全程处于真空体系中,既稳定高活性的锂,又提高锂与硫的反应程度,而浸入石墨中的锂在得到保护的同时,也将锂尺寸限制在微米级;所制备的硫化锂/石墨复合正极材料中锂基本上是处于石墨夹层内,产物中硫化锂含量为78.88%;硫化锂/石墨复合材料的结构更有利于电子传导,将其作为正极进行储能测试,势垒仅为3.0 V,比容量高达921.6 mAh/g。The preparation of lithium sulfide composite graphite materials is a hot topic for many scholars,and how to prepare high-capacity lithium sulfide composite graphite structural materials is of more research significance.At present,the method of graphite thermal reduction of lithium sulfate is used to produce this material on an industrial scale.The process requires a high-temperature system and belongs to a solid phase reaction.The reaction rate and particle size are limited by lithium sulfate.In this paper,the idea of preparing lithium sulfide/graphite composite cathode material by using high temperature to immerse lithium into a cheap graphite layer in a vacuum system and sulfurizing in the same system is proposed.The effects of various parameters on the lithium volatilization rate and lithium filling rate of the prepared materials were investigated.The main conclusions are as follows:The optimum leaching process parameters are the leaching temperature of 1173 K and the time of 180 min.The optimum vulcanization process parameters are the vulcanization temperature of 453 K and the time of 40 min.The reaction process is in a vacuum system,which not only stabilizes the highly active lithium but also improves the reaction degree of lithium and sulfur.The lithium immersed in graphite is protected and the lithium size is limited to the micron level.The lithium in the prepared lithium sulfide/graphite composite cathode material is basically in the graphite interlayer,and the content of lithium sulfide in the product is 78.88%.The structure of lithium sulfide/graphite composite is more conducive to electron conduction.It is used as a positive electrode for energy storage tests.The barrier is only 3.0 V,and the specific capacity is as high as 921.6 mAh/g.

关 键 词：硫化锂复合石墨结构材料 复合正极材料 熔浸-液相硫化 锂填充率 储能 比容量 势垒 

分 类 号：TF13[冶金工程—冶金物理化学] TM912[电气工程—电力电子与电力传动]