现场热引发聚丙烯酸酯类电解质的性能及应用

应用热引发现场聚合方法制备聚丙烯酸酯类电解质,并考察其电化学性能.实验表明:该聚合物电解质具有 4. 5V的电化学稳定窗口,较高的室温电导率及良好的低温性能.当前驱体电解液中液态电解质含量为 85%时,其室温电导率为 3. 2×10-3S·cm-1, -30℃下的电导率达到 5. 6×10-4 S·cm-1.采用现场聚合技术制备的聚合物电池,其电化学性能与液态锂离子电池基本一致,首次充放电效率为 92. 1%, 1. 0C率放电容量为 0. 2C率的 95%, -20℃下的放电容量为室温容量的 72%,以 0. 5C率循环 300周后,仍保持初始容量的 85%以上.

Electrochemical Performance of Gel Polymer Electrolyte Prepared by Thermal Initiating Polymerization of Acrylates

A gel polymer electrolyte was prepared by thermal initiating polymerization of the acrylates in the EC/EMC/DMC electrolyte solution at 100℃. The LiCoO_2/MCMB polymer cells were assembled and their electrochemical properties were evaluated at various charge-discharge rate and temperatures. The ionic conductivity of the polymer electrolyte containing 85wt.% liquid electrolyte is around 3.2×10~(-3)S·cm~(-1) at 20℃ and 5.6×10~(-4)S·cm~(-1)at -30℃ respectively. The gel polymer electrolyte has good electrochemical stability up to 4.5V versus Li/Li~(+).The first charge-discharge efficiency of the polymer cell at 0.2C rate is almost 92.1%. The discharge capacity of the cell at 1.0C rate is 95% of the capacity at the 0.2C rate and the discharge capacity of the cell at -20℃ is 72% of the capacity at the 20℃. The charge-discharge capacity of the polymer cell is stable with charge-discharge cycling.