SYNTHESIS AND CHARACTERIZATION OF Si-CNT BASED Li-ION BATTERY ANODE

Abstract

Secondary energy storage devices are in high demand owing to the recent developments in portable Electronic devices, Electric vehicles and Electric storage systems. In last two decades, Li-ion batteries have come out as one of the promising energy storage devices. Future applications require much higher energy storage capacity, than a conventional Li-ion battery. In order to improve specific capacity, retention ability and life of the battery, different anode materials like CNT, Sn02, Si etc were proposed. A pure Si anode is known to offer maximum theoretical specific capacity of 4200mAh/g. However, it's poor retention capacity due to the large volume change around 400% during the lithiation-delithiation process, hampers its wide acceptance. This problem could be addressed by incorporating different composite anode materials, Si-CNT composite is one of them. This dissertation deals with an easy route of synthesis and characterization of a Si-CNT composite based Liion battery anode. In this the CNTs were functionalized using HNO3 to make the interaction stronger between Si and CNT. Si was mixed with functionalised CNT by using simple probe ultrasonicator. As prepared Si-FCNT composite was pasted over a thin copper foil (current collector) using PVDF as binder. The prepared anode was characterised with different techniques such as XRD, FTIR and electrochemical characterisations. The prepared anode offered good initial specific capacity of 663mAh/g.