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Date of Award
Doctor of Philosophy (PhD)
As global energy consumption continues to rapidly increase, the need for new technologies to meet this demand in a sustainable way. Renewable sources such as solar and wind power are being increasingly utilized for electricity generation. However, the intermittent nature of these sources requires large-scale energy storage to reliably provide consistent power. Current grid-scale energy storage usually involves pumped hydroelectric systems, which are limited by location, or flywheel systems, which have limited use in high-power low-energy applications. Electrochemical storage solutions, such as lithium-ion batteries, provide robust energy storage that is not limited by location with a range of power and energy densities. Current lithium-ion battery technologies are used to power everything from electric vehicles (EVs) to handheld electronics. However, as the power and energy requirements of these devices continue to increase, new battery technologies will be needed. For example, the shift toward EVs faces issues related to vehicle batteries, including vehicle range, charging time, and cost.Thin-film batteries have several characteristics, such as high energy and power densities and long cycle life, that make them promising for next-generation lithium-ion batteries. Additionally, materials that have major drawbacks, such as large changes in volume during battery cycling, are possible to use in thin film systems. High-rate charging is also possible using thin film lithium-ion batteries due to the short distance lithium ions must intercalate during the charging process.In this thesis, an aerosol chemical vapor deposition (ACVD) technique is used to synthesize structured, single-crystal thin-film battery electrodes in a single-step process that operates at atmospheric pressure. Several materials were synthesized, such as SnO2, TiO2, and doped TiO2, for use as lithium-ion battery electrodes. A scale-up study on the ACVD reactor was conducted by developing a coupled computational fluid-dynamics Рaerosol dynamics model. This model was used to study the effect of reactor operating parameters on the resultant thin film morphology, deposition rate, and uniformity. Finally, a lithium-sulfur battery electrode was synthesized using a TiO2 thin film synthesized via ACVD combined with a metal-organic-framework synthesized using electrospray.
Richard Axelbaum, Sean Garner, Palghat Ramachandran, Vijay Ramani,
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