A nonaqueous asymmetric hybrid Li4Ti5O12/poly(fluorophenylthiophene) energy storage device

An asymmetric hybrid energy storage device has been built using a lithium titanate intercalation anode and the pseudocapacitive electronically conducting polymer poly(fluorophenythiophene). Results show that the device operates in the power range of electrochemical double-layer capacitors, while having three to four times their energy density, and a voltage profile and self-discharge characteristics typical of a battery. The cycle life is also intermediate between that of a battery and a supercapacitor, in the range of several thousands of cycles. (C) 2002 Telcordia Technologies.