长寿命、高倍率(Li4Ti5O12-AC)/( LiMn2O4-AC)电池电容的制备及性能研究

以商业微米级锰酸锂(LiMn2O4)为正极,钛酸锂(Li4Ti5O12)为负极,分别与商业活性炭(AC)复合,组装成软包装电池电容样品并进行电化学测试。测试结果表明：当样品正负极均复合AC时,其电化学性能要优于只有正极复合AC和未复合AC的样品。其中,正负极活性炭复合比例为5 wt.%,负极与正极的理论容量比(N/P)为1.01时,电池电容样品拥有良好的倍率性能,且其在0.5 C时的放电比容量为56.4 mAh/g,5 C时的容量保持率为0.5 C的72.2%。此外,与未复合AC的样品相比,单体在5 C倍率下经2000次循环后的容量保持率仍有77.5%,远高于前者的30.4%。

A long life and high rate (Li4Ti5O12-AC)/( LiMn2O4-AC) Hybrid Battery-Supercapacitor

The punch hybrid battery-supercapacitor samples with a commercial micro-scale Li4Ti5O12/activated carbon (AC) composite anode and a commercial micro-scale LiMn2O4/AC composite cathode are prepared and the electrochemical performance is characterized. The results show that Li4Ti5O12 AC/LiMn2O4 AC samples have better electrochemical performance compared with Li4Ti5O12 /LiMn2O4 AC samples and Li4Ti5O12 /LiMn2O4 lithium-ion battery samples. The sample with theoretical capacity of negative and positive (N/P) 1.01, containing 5 wt.% AC in each electrode, shows superior rate performance, meaning 56.4 mAh/g specific capacity at 0.5 C and 72.2% retention at 5 C rate. Besides, after 2000 cycles at the rate of 5 C, the capacity retention of cells is 77.5%, achieving a large improvement of the cycle life compared to Li4Ti5O12 /LiMn2O4 lithium-ion battery .