Investigation on Electrochemical Interface between Li[sub 4]Ti[sub 5]O[sub 12] and Li[sub 1+x]Al[sub x]Ti[sub 2−x](PO[sub 4])[sub 3] NASICON-Type Solid Electrolyte

An interface consisting of film electrode and -based NASICON (sodium superionic conductor)-type solid electrolyte (LTP) was prepared by a sol-gel coating method. The prepared solid-solid electrochemical interface was evaluated by cyclic voltammetry, galvanostatic discharge-charge test, and ac impedance method. The measured impedance of the interface between and LTP was about , and compressed semicircles were observed at all electrode potentials, indicating a presence of potential distribution at the electrochemical interface due to poor solid-solid contact between and LTP. In cyclic voltammograms of this electrochemical interface, a highly reversible sharp redox peak was observed at around . From discharge-charge tests, thin-film electrode on LTP showed high reversibility during discharge and charge cycles, and it exhibited discharge capacities of at rate and at rate, respectively.