Designing novel high performance anode materials for li ion batteries

Abstract

This thesis discusses original works done by Mr Kingshuk Roy on designing unique and novel anode materials for Li ion batteries The overall thesis is divided into four chapters and ends with an appendix The first chapter introduces the thesis followed by three working chapters Chapter 1 provides a brief idea about the global energy demand need for renewable energy sources and efficient energy storage devices to store the energy It also provides basic idea about the basic energy storage systems such as batteries and capacitors followed by their working principle Although there are exist various energy storage systems of interest this introduction chapter provides a detailed discussion of batteries especially Li ion battery and its working principle and the electrode materials which are being used in this device since the working chapters of this thesis are based on electrode materials for Li ion batteries Chapter 2 provides an original work on the very first report of a ternary intermetallic 3D carbide with unique antiperovskite structure involving both transition Fe and post transition Sn metals namely Fe3SnC as a stable high capacity anode material for Li ion battery DFT based computational studies reveal that Li insertion results in deviation from the cubic anti perovskite structure with a volume expansion that induces significant strain in the electrode as is evident from the XRD and SAED data We have also in situ synthesized Fe3SnC Carbon Nano Fiber CNF composite and realized a very impressive cyclic stability Initial discharge capacity was found to be 1045 mAhg 1 and along with a stable reversible capacity of 600 mAhg 1 at 200 mAg 1 and 500 mAhg 1 at 1 Ag 1 after 1000 charge discharge cycle with almost 96 retention of capacity Similarly exceptionally high rate performance was observed with a high value of 500 mAhg 1 obtained even at a current of 2 Ag 1 Fe3SnC is thus projected as a novel and very efficient material among the 3D carbide systems with the corresponding Li storage pe newline newline