Li_(6.6)La_(3)Zr_(1.6)V_(0.4)O_(12)复合PEO基固态电解质的制备及其性能研究

Preparation and Properties of Li_(6.6)La_(3)Zr_(1.6)V_(0.4)O_(12)Composite Polyethylene Oxide Composite Solid Electrolyte

复合固态电解质因其在提高能量密度和安全性方面的潜力而备受关注。通过固相烧结合成Li_(6.6)La_(3)Zr_(1.6)V_(0.4)O_(12),并将Li_(6.6)La_(3)Zr_(1.6)V_(0.4)O_(12)作为一种活性填料和聚氧化乙烯制备复合固态电解质。与纯聚氧化乙烯电解质相比,Li_(6.6)La_(3)Zr_(1.6)V_(0.4)O_(12)复合固态电解质膜不仅具有更好的离子电导率(25℃时为1.9×10^(-5)S·cm^(-1),80℃时为4.3×10^(-3)S·cm^(-1)),其锂离子转移数也有所提高,达到0.79。LiFePO_(4)/固态电解质/Li组装电池的初始放电容量达到177.4 m A·h·g^(-1);在高倍率(1 C)下,电池的比容量仍然为103.2 mA·h·g^(-1);复合固态电解质对称锂电池在50℃下可连续工作1000 h,无短路。Li_(6.6)La_(3)Zr_(1.6)V_(0.4)O_(12)作为活性离子导体,提高了固态电解质的整体性能。

Solid composite electrolytes have attracted much attention because of their potential in improving energy density and safety.Li_(6.6)La_(3)Zr_(1.6)V_(0.4)O_(12)was synthesized by high-temperature annealing,and a composite solid electrolyte with polyethylene oxide was formed.Compared with pure polyethylene oxide electrolyte membrane,the composite polymer electrolyte membrane had better ionic conductivity(25℃,1.9×10^(−5) S·cm^(-1);80℃,4.3×10^(-3) S·cm^(-1)).Because of Li_(6.6)La_(3)Zr_(1.6)V_(0.4)O_(12),the lithium ion transfer number of composite solid electrolyte was improved,which was as high as 0.79.The initial discharge capacity of Li/solid electrolyte/LiFePO_(4) was up to 177.4 mA·h·g^(-1).At high magnification(1 C),the specific capacity of the battery was still 103.2 mA·h·g^(-1).At the same time,the symmetrical lithium battery with composite electrolyte could work continuously for 1000 h without short circuit at 50℃.Li_(6.6)La_(3)Zr_(1.6)V_(0.4)O_(12)as an active ionic conductor,improved the overall performance of solid electrolyte.