溶胶-凝胶法制备稀土金属离子掺杂LiFePO_4/C正极材料及其电化学性能研究  

Preparation of Cathode Material LiFePO_4/C Doped with Rare Earth Metal Ions by Sol-Gel Method and Study on Its Electrochemical Performance

作　　者：袁铭[1] 梁蕾 龙秉文[1] 邓伏礼[1] 刘生鹏[1] 杨昌炎[1] 丁一刚[1] 

机构地区：[1]武汉工程大学化工与制药学院湖北省新型反应器与绿色化学工艺重点实验室绿色化工过程省部共建教育部重点实验室,湖北武汉430074 [2]湖北祥云(集团)化工股份有限公司,湖北黄冈435400

出　　处：《化学与生物工程》2015年第4期51-54,共4页Chemistry & Bioengineering

摘　　要：采用溶胶-凝胶法,在溶胶阶段分别掺杂不同量的Gd3+、Ce4+、Sm3+和Tm3+制备了一系列具有橄榄石晶体结构的LiFePO4/C正极材料,通过X-射线衍射、扫描电镜和电池测试对其组成、形貌及电化学性能进行了表征。结果表明:Sm3+和Tm3+的掺杂会使LiFePO4/C的电化学性能变差,而掺杂1%(质量分数,下同)Gd3+或2%Ce4+会使LiFePO4/C的电化学性能提高,其中掺杂1%Gd3+的效果最好,0.1C下LiFePO4/C的首次放电比容量可达135.7mAh·g-1。A series of olivine structure LiFePO4/C cathode materials were synthesized by sol-gel method and doped with Gda＋ ,Ce4＋ , Sm3＋ and Tma＋ at the stage of sol. The composition,morphology and electrochemical performance of LiFePO4/C were characterized by XRD,SEM and battery test,respectively. The results showed that the electrochemical performance of LiFePO4/C was downgraded with the doping of Sma＋ and Tma＋, but the doping of 1%Gda＋ or 2%Ce4＋ would improve the electrochemical performance of LiFePO4/C. The doping of 1 %Gd3＋ had the best effect,the initial discharge capacity of LiFePO4/C could reach 135.7 mAh · g-1 at 0.1 C.

关 键 词：溶胶-凝胶法 LIFEPO4 改性 稀土金属离子 电化学性能 

分 类 号：O646.5[理学—物理化学] TM911[理学—化学]