Development of Modified Silicon Based Electrode Materials for Advanced Generation Safer Lithium Based Batteries /

Abstract

Sustainable development is becoming more and more challenging for the entire human race with the ever-increasing number of engines up and running. The lithium-ion battery concept is designed for high-energy density, compact and environmentally acceptable rechargeable batteries. The main idea of research is promotion and enhancement of lithium based batteries. Current commercial lithium ion batteries are limited by the capacity of their electrode materials. Enlightening the lithium storing properties of a silicon negative electrode has prodigious implication for lithium-ion batteries. The core purpose is to develop Si-based active materials having structural design and upright electronic conduction in the process of de(lithiation). In this study, the mechanical ball milling technique has been employed and the effect of incorporation of different forms of carbon and graphene into silicon has been investigated in the development of hybrid silicon-based freestanding paper anode material for LIBs. The phase purity, morphology and elemental analysis of Si/C hybrid powder and Si/C/G hybrid freestanding paper based anodes were investigated using XRD, SEM, EDS, etc. Moreover, thermo-gravimetric/differential thermal analysis (TGA/DTA) of the pre-dried powders and freestanding paper based anodes was carried out up to 900⁰C to investigate the thermal decomposition behaviors. The obtained findings on the reduction of Si/C/GO into Si/C/G indicates the partial reduction of GO into G after treating the sample at 550⁰C in mixed Ar/6%H2 atmosphere. To investigate the electrical behavior of the electrode materials, CV, LSV and EIS has been carried out. Diffusion coefficients for Si/MWCNTs, Si/N2-Rich CNTs, Si/Carbon black Si/MWCNTs/G, Si/N2-Rich CNTs/G and Si/Carbon black/G were recorded to be (11.7x10-4 cm2/s)ORR, (11.7x10-5 cm2/s)ORR, (2.9x10-2 cm2/s)OER, (8.1x10-5 cm2/s)ORR, (3.8x10-8 cm2/s)ORR, (4.5x10-6 cm2/s)ORR, (4x10-2 cm2/s)OER and (6.1x10-3 cm2/s)ORR and exchange current densities were recorded to be (1.5 x10-3 A/cm2)ORR, (3.9 x10-3 A/cm2)ORR, (7.3 x10-3 A/cm2)OER, (2.2 x10-3 A/cm2)ORR, (3.92 x10-3 A/cm2)ORR, (1.27 x10-3A/cm2)ORR, (1.1 x10-3A/cm2)OER and (2.98 x10-3 A/cm2)ORR respectively. At the same time, nano-wired copper particles coated with carbon have been used to address the safety issue in lithium ion batteries. The testing of this material reveals that the material safely switches the battery off above its switching temperature. One notable feature of this material is its reversible operation allowing the battery to switch on and off multiple times without affecting the performance of the battery. Indeed, this study is expected to expedite the emergence of low-cost and sustainable silicon-carbon based electrode materials for safer LIBs applications.