Carbon Nanotubes as Effective Interlayer for High Performance Li-I2 Batteries: Long Cycle Life and Superior Rate Performance

Highly soluble active materials, such as iodine, are of great potential to develop the research of rapid charge-discharge performance for Li-ion batteries. In this work, a new facile method is applied to construct the iodine/carbon electrode system, which is composed of a thin cathode film, prepared by directly mixing pure commercial iodine and superconducting carbon black, and a carbon nanotubes (CNTs) interlayer. The CNTs interlayer is inserted between pure iodine cathode and separator in the lithium-iodine battery. Electrochemical data reveals that the iodine cathode demonstrates a high capacity of 100 mAh g(-1) and similar to 100% columbic efficiency after 5000 cycles at a rate of 100C, which shows a great cycle stability and superior high-rate capability, based on the contributions from both the confinement effect of iodine species in CNTs interlayer and the quick liquid-phase diffusion of Li ions in Li-I-2 battery. (C) 2018 The Electrochemical Society.