Micron-sized, carbon-coated Li4Ti5O12 as high power anode material for advanced lithium batteries

Abstract

Spherical, high tap density, carbon-coated Li4Ti5O12 powders are synthesized by a spray-drying process followed by a facile pitch coating. XRD, SEM, TEM analyses show that the carbon layer uniformly coats the Li4Ti5O12 particles without producing any crystalline changes. We demonstrate that the carbon coating significantly increases the electrical conductivity of Li4Ti5O12 making it an efficient, high rate electrode for lithium cells. The electrochemical tests in fact confirm that the 3.25 wt% carbon-coated Li4Ti5O12 electrode operates with ultra high rate capacity levels, i.e., 100 C and has excellent capacity retention and charge-discharge efficiency for a life extending over 100 cycles. (C) 2011 Elsevier B.V. All rights reserved.This research was supported by WCU (World Class University) program through the National Research Foundation of Korea funded by the Ministry of Education, Science and Technology (R31-10092), by the Human Resources Development of the Korea Institute of Energy Technology Evaluation and Planning (KETEP) grant funded by the Korea government Ministry of Knowledge Economy (No. 20104010100560), and by Basic Science Research Program through the National Research Foundation of Korea (NRF) grant funded from the Ministry of Education, Science and Technology (MEST) of Korea for the Center for Next Generation Dye-sensitized Solar Cells (No. 2010-0001842)