Mn3O4/carbon as a prospective anode for Li-ion cells

Abstract

Lithium ion batteries are widely investigated to ensure best performance and long life span of portable electronic devices. For high-energy applications like electric automobiles (EV) and hybrid electric vehicles (HEV), Li-ion batteries with much higher energy density are mandatory. High energy density LIBs work on silicon or transition metal oxides (MxOy, where M can be Co, Mn, Fe and Ni) based anodes. Theoretically, Mn3O4 has quite high capacity around 936 mAhg−1, has the lowest electromotive force, is environmentally friendly, has an abundance of resources, and has the lowest hazardous level. However, pure Mn3O4 has many limitations, including low electrical conductivity (10-7 to 10-8 Scm−1), significant volume expansion during lithium insertion/extraction, and the development of unstable solid electrolyte interface (SEI) coating. To address these issues, one of the most viable approaches is the use of conducting polymers or carbonaceous materials like carbon nanotubes (CNT) or graphene for increasing electrical conductivity and limiting volume expansion. Nanostructures with different morphologies embedded in networks or nanocomposites with various types of porous materials help to accommodate the volume change.In this study, Mn3O4 and Mn3O4/C nanocomposite, synthesized via a simple one-pot synthesis route, have been investigated to assess their prospects as anode materials for Li-ion cells. Half-cells assembled using nanostructured Mn3O4 show appreciable capacity with capacity retention of 17% after 50 cycles. Cells based on Mn3O4-carbon nanocomposite are seen to deliver initial specific discharge capacity and specific charge capacity of 1321 mAhg−1 and 428 mAhg−1, respectively, with capacity retention of 24% after 50 cycles.