| Anode material Li4Ti5O12 was prepared by solid state reaction and characterized by X-ray diffraction, Scan electron microscope, Cyclic voltammetry, Electrochemical Impedance Spectroscopy and constant current charge/discharge techniques. According to those, the samples were modified by doping of activated carbon, SnO2, Sb2O3 and Bi2O3. The experiments indicated that the performance of samples by wet mixing method was better with the initial discharge capacity of 163.1mAh·g-1 and the capacity loss was only 4.4% after 60 cycles in half cell. And the initial discharge capacity was 122.2mAh·g-1 in integrated cell with the capacity loss of 7.6% after 100 cycles. Calcination process was amended by reduce the grain diameter to the scope of 0.7～0.9μm after addition of activated carbon and the sample's initial discharge capacity was 121.9mAh·g-1 with the loss of 2.6% after 100 cycles. The capacity was about half of that when the current density was 10 times larger. New phase was detected in Sb2O3 doped sample and the sample gave the initial discharge capacity of 595.8mAh·g-1 and remained 249.6mAh·g-1 after 20 cycles with the ratio of Ti:Sb was 4:1. When doped by Bi2O3, the discharge capacity was found to increase with the increasement of Bi. And the largest capacity was 680.0mAh·g-1 with the reversible efficiency of 43.7%. While coupled with activated carbon cathode in asymmetry hybrid capacitor, Li4Ti5O12 revealed pseudocapacitance due to the incomplete reaction, and the initial discharge capacitance was 69.9F·g-1 with the remained capacity of 61.2F·g-1 after 800 cycles at the current density of 0.5mA·cm-2.
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