摘要
锡基材料具有工作电压低、理论容量高等优点,是极具发展前景的锂离子电池负极材料。但其在循环充放电过程中,易发生严重的体积膨胀和结构坍塌,导致容量衰减严重,用多孔碳材料包覆后形成复合材料,是解决该缺陷的有效手段。本文以石油沥青为碳源和硫源,与Sn O_(2)混合后在高温下通过碳还原,制备了一种碳包覆的Sn/Sn S@C复合材料,采用XRD、SEM、TEM进行了表征,并测试了其电化学性能。沥青在高温下得到的碳为层状结构的非孔状材料,使用该碳材料包覆的Sn/Sn S@C复合材料,比容量约为沥青碳材料的2倍,在0.1A·g~(-1)电流密度下的首圈放电比容量为944.4 mAh·g~(-1),之后随着充放电的进行,比容量逐渐降低,100圈循环后容量保持在527.6m Ah·g~(-1),比容量保持率为55.9%。为保证复合材料的容量稳定性和充放电可逆性,SnO_(2)的掺杂量以10%左右为宜。
Tin-based materials had the advantages of low operating voltage and high theoretical capacity,which was a promising anode material for lithium ion batteries.However,severe volume expansion occured during cycling,resulting in a rapid decreased in capacity.Coating with carbon materials was an effective means to overcome defects.In this paper,the carbon coated Sn/SnS@C composites were prepared via carbon reduction by mixing petroleum asphalt with SnO_(2) at high temperature,in which the petroleum asphalt was used as carbon and sulfur sources.The synthesized composites were characterized by XRD,SEM,and TEM,and the electrochemical performance was tested.The carbon obtained from petroleum pitch at high temperature was lamellar non-porous material.The specific capacity of Sn/SnS@C composite coated by this carbon material was about twice that of the prepared carbon material,and the initial discharge capacity was 944.4mAh/g at the current density of 0.1A/g,then the specific capacity gradually decreased,and remained at 527.6 mAh/g over 100 cycles with a retention rate of 55.9%.To ensure the capacity stability and the charging/discharging reversibility,the doped amount of SnO_(2) was about 10%.
作者
李春玲
卢秋影
龚福忠
李艳琳
卓民权
王超
黄世勇
LI Chunling;LU Qiuying;GONG Fuzhong;LI Yanling;ZHUO Minquan;WANG Chao;HUANG Shiyong(School of Chemistry and Chemical Engineering,Guangxi University,Nanning 530004,China;Guangxi Chemical Research Institute Co.,Ltd.,Nanning 530001,China;Guangxi Key Laboratory of Petrochemical Resource Processing and Process Intensification Technology,Nanning 530004,China)
出处
《化工技术与开发》
CAS
2023年第7期1-6,共6页
Technology & Development of Chemical Industry
基金
广西石化资源加工及过程强化技术重点实验室项目(2021Z001)。
关键词
石油沥青
锡-碳复合材料
负极材料
比容量
petroleum pitch
tin-carbon material
anode material
specific capacity
