A (LiFePO[sub 4]–AC)∕Li[sub 4]Ti[sub 5]O[sub 12] Hybrid Battery Capacitor

In this work, we synthesized a composite cathode material containing and activated carbon (AC), which is abbreviated as LAC, by a solid-state reaction, and assembled a hybrid battery-capacitor . The electrochemical performances of the hybrid battery-capacitor were characterized by cyclic voltammograms, constant current charge-discharge, rate charge-discharge, and cycle performance testing. The results show the hybrid battery-capacitor has advantages of the high rate capability of hybrid capacitor and the high capacity of battery . It is also proven that the hybrid battery-capacitor is an energy storage device where the capacitor and the secondary battery coexist in one cell system.