自由基聚合物锂二次电池正极材料

Polyradical cathode materials for lithium secondary batteries

PTMA[聚(2,2,6,6 四甲基哌啶 4 甲基丙烯酸酯 1 氮氧自由基)]的循环伏安曲线(扫描速度:10mV/s)表明PTMA具有良好的氧化还原反应可逆性和循环稳定性。PTMA的最大放电比容量为78 4mAh/g[以0 3mA(0 2C)充放电],是它理论比容量(111mAh/g)的70 6%,充放电曲线分别在3 65V(vs Li/Li+)和3 56V(vs Li/Li+)处有一个很平稳的平台,经过100次循环后电池的放电比容量相对于最大放电比容量只衰减了2%,以10C的充电速度6min能充满电池容量的85 5%,表明锂/PTMA扣式电池具有优良的循环性能和快速充放电性能。

Cyclic voltammetry(scan rate:10?mV/s)of PTMA[poly (2,2,6,6-tetramethylpiperidinyloxy methacrylate)] showed that PTMA possessed an excellent reversibility and cyclic stability. The maximum discharge specific capacity of PTMA was 78.4?mAh/g, which was 70.6 % of the theoretical special capacity(111?mAh/g), at a constant discharge current of 0.3?mA (0.2C). In the charging /discharging curves, there were obvious voltage plateaus at 3.65?V and 3.56?V, respectivly.After 100 cycles, about 2% of the maximum specific capacity of PTMA was lost.Furthermore, 85.5% of the maximum specific capacity of PTMA could be charged just in 6 min at a constant charge rate of 10C. It indicated excellent stability and fast charging-discharging properties of PTMA/Li button cell.