Angathevar Veluchamy

Analysis on the Formation of Li 4 SiO 4 and Li 2 SiO 3 through First Principle Calculations and Comparing with Experimental Data Related to Lithium Battery

The formation of Li-Si-O phases, and from the starting materials SiO and are analyzed using Vienna Ab-initio Simulation (VASP) package and the total energies of Li-Si-O compounds are evaluated using Projector Augmented Wave (PAW) method and correlated the structural characteristics of the binary system SiO- with experimental data from electrochemical method. Despite becomes stable phase by virtue of lowest formation energy calculated through VASP, the experimental method shows presence of as the only product formed when SiO and reacts during slow heating to reach and found no evidence for the formation of . Also, higher density of (2.42 g ) compared to the compositional mixture (2.226 g ) and better cycle capacity observed through experiment proves that as the most stable anode supported by better cycleabilityfor lithium ion battery remains as paradox from the point of view of VASP calculations.

Silicon Based Composite Anode for Lithium Ion Battery

The invention of Voltaic pile during 1800 by the Italian Physicist, Alessandro Volta brought new light and energy into the world through Direct Current (DC) producing device known as battery which performed operations in domestic, industrial and transport equipments. These batteries are divided broadly into two categories one the primary battery and the other rechargeable battery. Few examples of primary batteries are the non-aqueous lithium batteries, and the zinc and magnesium based batteries. The prominent and well established rechargeable batteries are lithium-ion, lead-acid, nickel-metal hydride and nickelcadmium, silver-zinc systems (Balasubramanian et al., 1994, 1995; Jose Benedict et al., 1998; Renuka et al. 1992; Veluchamy et al., 2001, April 2009). Recently, the cost escalation of petroleum fuel has turned the attention of policy makers and researchers toward battery powers systems in order to partly/completely replace the petroleum fuels for automotive applications. Among the battery systems considered for electric vehicle (EV) applications, the lithium ion batteries show promise of meeting both energy and power requirements. The possibility of developing high energy and safe lithium ion battery has been reinforced further by the statement of (Panasonic, 2010) which reports a silicon-carbon nanocomposite anode for the lithium ion battery, with 30% higher capacity than the graphite based lithium ion cells, has been intended to provide power to laptop computers during the fiscal 2012. To make economic viability and practical implementation, especially for EV application still more work has to be done on fronts such as improvements on energy/power capability and safety. To meet this requirement work has to be pursued on battery materials development with a special emphasis on cost and environments. For transport applications attempts have to be made to replace combustible organic electrolytes, oxygen releasing cathodes and reactive lithium anode. This chapter presents development of high specific capacity anode materials especially the silicon composite anode material for lithium ion batteries. The resource material for this chapter has been gathered from recent research publications on lithium anode materials development.

Thermo-Chemical Process Associated with Lithium Cobalt Oxide Cathode in Lithium Ion Batteries

The concept of galvanic couple and the development of battery and fuel cells made possible the direct current (DC) producing devices for practical applications. Even though, existing aqueous electrolyte based power sources such as lead acid, nickel metal-hydride, nickelcadmium, alkaline/dry zinc based batteries and magnesium systems reached mature level of technology, the lithium based non-aqueous cell system (Plitcha et al., 1987) is able to penetrate and steadily expand its market share. Notwithstanding high cost, the lithium cells became the candidate of choice for miniature application and also for futuristic power pack for electric vehicle propulsion owing to its light weight, high voltage, high energy density and low self discharge characteristics. Present day lithium rechargeable cells are constructed usually by coupling a graphite anode and any one of the cathodes among lithium cobaltate(LixCoO2), lithium manganese spinel (LixMn2O4), Lithium iron phosphate LixFePO4(Olivine) and lithium Nickelate (LixNiO2) in an air tight pouch or in a metal container. Assisted by potential difference between the anode and cathode electricity (electrons) flows from LiC6(lithium intercalated graphite) anode to the cathode through an external load accompanying simultaneously Li+ ion de-intercalation from the anode and intercalation at the cathode, maintains charge neutrality in the electrodes for which the electrolyte plays the role of transporting Li+ ions.