Y^(3+)、F^-共掺杂钒酸锂材料的电化学及存放性能研究  

Electrochemical and Storable Properties of LiV_3O_8 Cathode Material through Y^(3+) and F^- Co-substitution

作　　者：刘永梅[1] 李惠娟[1] 倪杰[1] 

机构地区：[1]西南林业大学西南山地森林资源保育与利用重点实验室,昆明650224

出　　处：《材料导报（纳米与新材料专辑）》2011年第1期304-308,共5页

基　　金：云南省教育厅基金资助项目(2010Y291)

摘　　要：利用干冷空气淬火法合成了Y^(3+)、F^-共掺杂的LiV_3O_8材料。XRD结果表明Y^(3+)、F^-共掺杂能"收缩"晶格。电化学测试结果表明由掺杂引入的杂质是非电化学活性的,共掺杂样有更多的锂离子嵌脱位置和更好的循环稳定性。存放实验表明共掺杂能降低电池自放电率。在高电压下存放15天后,共掺杂样的容量保持为存放前的92.4%,高于未掺杂样品。Y^3＋ and F^- co-substituted LiVaOs was synthesized by a novel solid-state reaction. XRD tests show that Y^3＋ and F^- co-substitutions can shrink the crystal lattice. The cyclic voltammetry, charge-discharge and electro- chemical impedance spectroscopy tests show that the impurities from the dopant are non-electrochemical activity, the doped sample has more Li＋ ions insertion/extraction sites and better cyclic ability. The storage tests show that y^3＋ and F^- co-substitutions can reduce the self discharge during the storage process, the capacity retention maintains at 92.4% for 15 days storage at high voltage, it is higher than that of the undoped sample.

关 键 词：LiV_3O_8 Y^3+、F^-共掺杂 存放性能 正极材料 

分 类 号：O646[理学—物理化学]