The worldwide market of lithium-ion batteries (LIBs) is growing at a rapid pace due to its increasing demand in electric vehicles (EVs), portable electronic devices, and energy storage systems. Due to the associated space constraint and requirement of low maintenance cost in these applications, anode material with high energy density, fast charging/discharging capability, low lithiation/delithiation potential, long cycle life, and high safety, is in demand. However, all low potential and high energy anode materials suffer from severe volume changes over complete lithiation/delithiation, which affects the cycle life of the LIB. Hence, the current research trend in the area of anode material is mainly focused on the finding of a novel anode material which can meet all of the aforementioned requirements for the EVs.



Graphite, the most used anode material in commercial LIB, exhibits limited fast-charging capability, which is a major impediment for EV applications. Single-walled carbon nanohorns (SWCNHs) are considered to be a promising anode material for lithium-ion battery applications. Owing to its excellent mechanical, electrical, thermal properties, high surface area, large pore volume, and good electrolyte permeability, SWCNHs could be a promising anode material or conductive matrix for anode materials having poor electrical conductivity and high volume expansion, thereby increasing the overall energy density and lifetime of the cell.


In this work, SWCNHs-based and SWCNHs-derived graphene-based anode materials are synthesized, and their electrochemical performance is studied for LIB applications. SWCNHs show good lithium storage capacity, excellent rate capability, and excellent cycle life at room temperature. An increase in the lithium storage capability of SWCNHs is observed with an increase in the temperature. As a composite anode material, SWCNHs are found to be significantly increasing the electrochemical performance and energy density of α-MoO3, WO3, and Sn, irrespective of their structure, morphology, and lithium storage mechanism.


Micrometer-length graphene sheets were synthesized by unzipping of SWCNHs without any formation of oxides. The obtained graphene sheets showed good electrical properties (three orders of magnitude higher than that of SWCNHs) and better lithium storage capability as compared to graphene nanoribbons synthesized via unzipping of carbon nanotubes. This unzipping technique was used to synthesize in-situ graphene-enwrapped α-MoO3, which showed improved lithium storage properties.

With the merits of scalable synthesis technique, high capacity, excellent rate capability, and long cycling stability, SWCNHs-based and SWCNHs-derived graphene-based anode materials could be promising anode materials for high energy and high power LIB applications.