通过对钛酸锂（LTO）负极进行电化学预锂化能够解决活性炭/钛酸锂（AC/LTO）混合型超级电容器在1.5~2.0 V电位区间的“跳水”现象（有电压没容量）。软包装AC/LTO超级电容器件的恒流充放电和循环伏安测试结果表明；当AC与LTO质量比为2：1，负极预锂化程度为5%~30%（按LTO实际容量150 mAh/g计）时，超级电容器在1.5~2.0 V低电位区间的容量显著提高。尤其当预锂化程度为20%时，器件在1.5~2.8 V全电压窗口呈现良好的线性充放电行为，同未预锂化的单体相比，比能量提高20%以上，100C电流下能量保有率为5C时的63%，表现出优异的倍率性能。但过度预锂化会导致负极容量不足，对器件性能造成不良影响。%The pre-lithiated lithium titanate is used as the anode for the fabrication of active carbon/lithium titanate (AC/LTO) supercapacitor to solve thediving phenomenon rangingfrom 1.5 V to 2.0 V. The constant current charge-discharge and cyclic voltammetry tests of soft-package AC/LTO hybrid supercapacitor depict that when the mass ratio of AC to LTO maintains 2/1 and the degree of pre-lithiation ranges from 5% to 30% (take LTO actual capacity as 150 mAh/g), the capacity of device at the lower voltage rangingfrom 1.5 V to 2.0 V is remarkably improved. Specifically, with the pre-lithiation degree fixed at 20%, the device exhibits well linear charge-discharge behavior at full-voltage window from 1.5 V to 2.8 V and the specificenergy increases by over 20% in contrast with that of un-lithiated sample. Also, the energy retention at 100C reaches 63% of that at 5C current, which shows excellent rate performance. However, excessive pre-lithiation can lead to the deficiency of anode,which causes the side effect to the performance of device.
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