长寿命高倍率(Li_4Ti_5O_(12)-AC)/(LiMn_2O_4-AC)电池电容的制备及性能

Preparation and Performance of a Long Life and High Rate(Li_4Ti_5O_(12)-AC)/(LiMn_2O_4-AC) Hybrid Battery-Supercapacitor

以商业微米级锰酸锂(Li Mn2O4)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AC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0.5C时的放电比容量为56.4m Ah/g,5C时的容量保持率为0.5C的72.2%。此外,与未复合AC的样品相比,单体在5C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%。

The punch hybrid battery-supercapacitor samples with a commercial micro-scale Li4Ti5O（12）/ activated carbon（ AC） composite anode and a commercial micro-scale Li Mn2O4/ AC composite cathode were prepared,and their electrochemical performances were characterized. The results showed that Li4Ti5O（12）＋ AC / Li Mn2O4＋ AC samples have better electrochemical performance compared with Li4Ti5O（12）/ Li Mn2O4＋ AC samples and Li4Ti5O（12）/Li Mn2O4lithium-ion battery samples. The Li4Ti5O（12）＋ AC / Li Mn2O4＋ AC sample with ratio of theoretical capacity of negative and positive（ N / P） 1. 01,containing 5（ wt） % AC in each electrode,showed superior rate performance,meaning 56. 4 m Ah / 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 of prepared hybrid battery-supercapacitor samples was 77. 5%,achieving a large improvement of the cycle life compared to Li4Ti5O（12）/ Li Mn2O4lithium-ion battery.