Of all the rechargeable batteries, the Li-ion battery is becoming the system of choice to power many portable and non-portable devices because of its light weight, good overall performance and high energy density, 125 – 150 Wh/kg. The work presented here relates to the development of advanced nanomaterials to address the requirements of secondary rocking chair batteries.

Nanostructured intercalating electrodes enhance the performance of rechargeable rocking chair and asymmetric hybrid batteries. The objective of this work has been to develop a variety of cathode (e.g., V2O5, LiMnO2 and LiFePO4) and anode (e.g., Li4Ti5O12) materials with unique particle characteristics and controlled composition. Different processing routes, which were chosen on the basis of the final composition and the desired particle characteristics of electrode materials, were developed to synthesize a variety of electrode materials. Vapor phase processes were used to synthesize nanopowders of V2O5 and TiO2. TiO2 was the precursor used for producing ultrafine particles of Li4Ti5O12. Liquid phase processes were used to synthesize nanostructured LiMnxM1-xO2 and LiFePO4 powders. It was found that (i) nanostructured V2O5 powders with a metastable structure have 30% higher retention capacity than their coarse-grained counterparts, for the same number of cycles; (ii) the specific capacity of nanostructured LiFePO4 cathodes can be significantly improved by intimately mixing nanoparticles with carbon particles, and that cathodes made of LiFePO4/C composite powder exhibited a specific capacity of ~ 145 mAh/g (85% of the theoretical capacity); (iii) nanostructured, layered LiMnxM1-xO2 cathodes demonstrated a discharge capacity of ~ 245 mAh/g (86% of the theoretical capacity) at a slow discharge rate; however, the composition and structure of the nanoparticles need to be optimized to improve their rate capabilities; and (iv) unlike micron-sized (1 – 10 mm) powders, ultrafine Li4Ti5O12 showed exceptional retention capacity at a discharge rate as high as 10C in Li-test cells.