A high concentration of lithium, corresponding to charge capacity of ∼4200 mAh/g, can be intercalated in silicon. Unfortunately, due to high intercalation strain leading to fracture and consequent poor cyclability, silicon cannot be used as anode in lithium ion batteries. But recently interconnected hollow nano-spheres of amorphous silicon have been found to exhibit high cyclability. The absence of fracture upon lithiation and the high cyclability has been attributed to reduction in intercalation stress due to hollow spherical geometry of the silicon nano-particles.

A first principle based study of the electrochemical properties of LiCoBO3 has been carried out. The theoretical energy density of LiMBO3 (M = Mn, Fe, Co) is comparable with the corresponding olivine phosphate. Low volume change during cycling gives it structural stability during full charging and discharging, hence making it a promising battery material. A 12.5% cation substitution with Mg, Mn, Ni, Cu and Zn was chosen to evaluate the electrochemical properties of the compounds.

This is CSTEP's Annual Report for the year 2011-12.

Steel and cement have become engineering workhorses for the industrial world. They may lack the glamour one perceives in novel materials, but they provide the wherewithal for building a prosperous and equitable industrial world.

There are no easy answers to India's quest for energy security with environmental sustainability. The electric power sector appears to be more  manageable, given India's thrust in nuclear power. The coming decades might see large additions in nuclear power generation capacity without
significantly increasing the CO2 emissions. The Indo-US nuclear agreement provides an opportunity to import LWRs and gives India time to commercialize the FBR and thorium-based reactors. At the same time, it will help to reduce India's dependence on coal to some extent.

A sodium-ion battery (NIB) cathode performance based on ammonium vanadate is demonstrated here as high capacity, long cycle life and good rate capability. The simple preparation process and morphology study enable us to explore this electrode as suitable NIB cathode. Furthermore, density functional theory (DFT) calculation is envisioned for the NH4V4O10 cathode and three possible sodium arrangements in the structure are depicted for the first time. Relevant NIB-related properties have been derived like average voltage, lattice constants and atomic coordinates etc.

Electrolytes enable conduction of ions in a battery across the electrodes. One of the most important properties of an electrolyte material is its electrochemical window, which determines overall safety of the battery. Electrochemical window (also known as HOMO LUMO gap or bandgap) is calculated in the present work for polyethylene oxide (PEO) with different chemistries using a combination of Hartree-Fock and density functional theory (DFT) techniques. The aim is to study how the bandgap can be varied with different functional groups added to the polymer.

This is CSTEP's Annual Report for the year 2010-11.

The threat of climate change is a serious global concern. There is near consensus among scientists that the threat is due to man-made emissions of Greenhouse Gases (such as Carbon Dioxide, Methane, Nitrous Oxides, etc).

Sodium intercalation batteries might prove to be a viable alternative of lithium ion batteries, which is both expensive and in short supply due to unavailability of lithium .Renewable energy sources being crucial to India's energy future, there is a huge need to develop scalable and cost effective storage technology with earth abundant materials to provide load balancing. Moving from lithium to sodium ion intercalation materials, electrochemical properties change significantly and electrochemical potential of intercalation drops.