利用Ce2S3对70Li2S-30P2S5玻璃陶瓷态电解质掺杂改性的研究  

Modification of 70Li2S-30P2S5 glass-ceramic electrolytes by Ce2S3 doping

作　　者：张楠[1,2] 钟学奇[1,2] 丁飞 赵旭升[3] 刘兴江 徐强[1] ZHANG Nan;ZHONG Xue-qi;DING Fei;ZHAO Xu-sheng;LIU Xing-jiang;XU Qiang(School of Chemical Engineering and Technology,Tianjin University,Tianjin 300072,China;National Key Laboratory of Science and Technology on Power Sources,Tianjin Institute of Power Sources,Tianjin 300384,China;School of Chemistry and Chemical Engineering,Qinghai Nationalities University,Xining 810007,China)

机构地区：[1]天津大学化工学院,天津300072 [2]中国电子科技集团公司第十八研究所物理与化学电源国防重点实验室,天津300384 [3]青海民族大学化学化工学院,青海西宁810007

出　　处：《高校化学工程学报》2020年第1期200-207,共8页Journal of Chemical Engineering of Chinese Universities

基　　金：天津市自然科学基金(17JCYBJC20900)

摘　　要：为了提高70Li2S-30P2S5玻璃陶瓷态电解质的离子电导率和电化学性能,提出利用Ce2S3掺杂改性的方法。采用高能球磨和热处理相结合的方法制备了一系列组分为70Li2S-(30-x)P2S5-xCe2S3(x=0,0.5,1,2,3)的玻璃陶瓷态电解质。通过差示扫描量热法(DSC),X射线衍射(XRD),拉曼光谱,扫描电子显微镜(SEM)和电化学测试等表征手段,对掺杂不同比例Ce2S3的Li2S-P2S5基固体电解质进行分析测试。研究结果表明:掺杂适量的Ce2S3不仅可以提高70Li2S-30P2S5玻璃陶瓷态电解质的离子电导率,还可以降低其与正极材料的界面电阻。其中,掺杂1%Ce2S3得到的70Li2S-29P2S5-1Ce2S3玻璃陶瓷态电解质表现出最高的室温离子电导率(1.52×10^-3 S·cm^-1),明显高于70Li2S-30P2S5玻璃陶瓷态电解质的室温离子电导率。对比LiCoO2/70Li2S-30P2S5/Li-In和LiCoO2/70Li2S-29P2S5-1Ce2S3/Li-In 2种全固态锂电池,后者表现出更好的放电性能,在室温下0.1C时的初始放电比容量为105.3 mAh·g^-1,循环50圈后的放电比容量为91.8 mAh·g^-1,容量保持率为87.2%。Ce2S3 doping was applied to improve the ionic conductivity and electrochemical performance of 70Li2S-30P2S5 glass-ceramic electrolytes.A series of glass-ceramic electrolytes of 70Li2S-(30-x)P2S5-xCe2S3(x=0,0.5,1,2,3)were prepared by high-energy ball milling combined with heat-treatment.Li2S-P2S5 based solid electrolytes doped with different ratios of Ce2S3 were investigated by differential scanning calorimetry(DSC),X-ray diffraction(XRD),Raman spectroscopy,scanning electron microscopy(SEM)and electrochemical measurements.The results show that the ionic conductivity of 70Li2S-30P2S5 glass-ceramic electrolytes can be improved by Ce2S3 doping,and the interfacial resistance between 70Li2S-30P2S5 glass-ceramic electrolytes and cathode materials can be reduced.The 70Li2S-29P2S5-1Ce2S3 glass-ceramic electrolyte doped with 1%Ce2S3 exhibited the highest ionic conductivity(1.52×10^-3 S·cm^-1)at room temperature,which was significantly higher than that of 70Li2S-30P2S5 glass-ceramic electrolyte.LiCoO2/70Li2S-29P2S5-1Ce2S3/Li-In showed better discharge performance than LiCoO2/70Li2S-30P2S5/Li-In,which had an initial discharge specific capacity of 105.3 mAh·g^-1 at 0.1C under room temperature.Its discharge specific capacity after 50 cycles was 91.8 mAh·g^-1 with capacity retention of 87.2%.

关 键 词：掺杂 三硫化二铈 硫化物固体电解质 离子电导率 全固态锂电池 

分 类 号：TQ152[化学工程—电化学工业]