An organic cathode material based on a polyimide/CNT nanocomposite for lithium ion batteries

Abstract

In this paper, a 3,4,9,10-perylenetetracarboxylic dianhydride/carbon nanotube (PTCDA/CNT) nanocomposite and its corresponding polymer nanocomposite poly(3,4,9,10-perylenetetracarboxylic dianhydride ethylene diamine)/carbon nanotube (PI/CNT) were produced, which could be used as organic cathode materials for lithium ion batteries. Compared with PTCDA, PTCDA/CNT exhibited an enhanced rate capability, and the capacity was increased from 10 mA h g⁻¹ to 115 mA h g⁻¹ at 2 C. Polymerization can further increase the cycling stability of organic cathode materials. The capacity of the polymer nanocomposite PI/CNT remained at 93% after 300 cycles under a current of 100 mA g⁻¹, while the capacity of PTCDA/CNT was only 74% after 300 cycles. The improved electrochemical properties of these materials were ascribed to increased electronic conductivity of PTCDA due to the formation of composites with CNTs, and their decreased solubility in the electrolyte due to polymerization.