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Lithium ion batteries are quintessential components of modern life. They are used to power smart devices — phones, tablets, laptops, and are rapidly becoming major elements in the automotive industry. Demand projections for lithium are skyrocketing with production struggling to keep up pace. This drive is due mostly to the

Lithium ion batteries are quintessential components of modern life. They are used to power smart devices — phones, tablets, laptops, and are rapidly becoming major elements in the automotive industry. Demand projections for lithium are skyrocketing with production struggling to keep up pace. This drive is due mostly to the rapid adoption of electric vehicles; sales of electric vehicles in 2020 are more than double what they were only a year prior. With such staggering growth it is important to understand how lithium is sourced and what that means for the environment. Will production even be capable of meeting the demand as more industries make use of this valuable element? How will the environmental impact of lithium affect growth? This thesis attempts to answer these questions as the world looks to a decade of rapid growth for lithium ion batteries.

ContributorsMelton, John (Author) / Brian, Jennifer (Thesis director) / Karwat, Darshawn (Committee member) / Chemical Engineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2021-05
Description
Current Li-ion battery technologies are limited by the low capacities of theelectrode materials and require developments to meet stringent performance demands for future energy storage devices. Electrode materials that alloy with Li, such as Si, are one of the most promising alternatives for Li-ion battery anodes due to their high capacities. Tetrel (Si,

Current Li-ion battery technologies are limited by the low capacities of theelectrode materials and require developments to meet stringent performance demands for future energy storage devices. Electrode materials that alloy with Li, such as Si, are one of the most promising alternatives for Li-ion battery anodes due to their high capacities. Tetrel (Si, Ge, Sn) clathrates are a class of host-guest crystalline structures in which Tetrel elements form a cage framework and encapsulate metal guest atoms. These structures can form with defects such as framework/guest atom substitutions and vacancies which result in a wide design space for tuning materials properties. The goal of this work is to establish structure property relationships within the context of Li-ion battery anode applications. The type I Ba 8 Al y Ge 46-y clathrates are investigated for their electrochemical reactions with Li and show high capacities indicative of alloying reactions. DFT calculations show that Li insertion into the framework vacancies is favorable, but the migration barriers are too high for room temperature diffusion. Then, guest free type I clathrates are investigated for their Li and Na migration barriers. The results show that Li migration in the clathrate frameworks have low energy barriers (0.1- 0.4 eV) which suggest the possibility for room temperature diffusion. Then, the guest free, type II Si clathrate (Na 1 Si 136 ) is synthesized and reversible Li insertion into the type II Si clathrate structure is demonstrated. Based on the reasonable capacity (230 mAh/g), low reaction voltage (0.30 V) and low volume expansion (0.21 %), the Si clathrate could be a promising insertion anode for Li-ion batteries. Next, synchrotron X-ray measurements and pair distribution function (PDF) analysis are used to investigate the lithiation pathways of Ba 8 Ge 43 , Ba 8 Al 16 Ge 30 , Ba 8 Ga 15 Sn 31 and Na 0.3 Si 136 . The results show that the Ba-clathrates undergo amorphous phase transformations which is distinct from their elemental analogues (Ge, Sn) which feature crystalline lithiation pathways. Based on the high capacities and solid-solution reaction mechanism, guest-filled clathrates could be promising precursors to form alloying anodes with novel electrochemical properties. Finally, several high temperature (300-550 °C) electrochemical synthesis methods for Na-Si and Na-Ge clathrates are demonstrated in a cell using a Na β’’-alumina solid electrolyte.
ContributorsDopilka, Andrew (Author) / Chan, Candace K (Thesis advisor) / Zhuang, Houlong (Committee member) / Peng, Xihong (Committee member) / Sieradzki, Karl (Committee member) / Arizona State University (Publisher)
Created2021
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Single-use plastic has rapidly increased pollution in the United States, and the urgency to address its growing consequences is a complex undertaking. Significantly contributing to plastic pollution is the waste of single-use beverage plastics like cups and straws. In order to make impactful changes in the supply chain of single-use

Single-use plastic has rapidly increased pollution in the United States, and the urgency to address its growing consequences is a complex undertaking. Significantly contributing to plastic pollution is the waste of single-use beverage plastics like cups and straws. In order to make impactful changes in the supply chain of single-use beverage plastics, we must first understand the stakeholders involved and the current extent of their actions. Therefore, this paper will investigate how stakeholders elicit sustainable changes to improve supply chain practices in this particular situation. We will use principles of sustainable supply chain management including corporate social responsibility and the triple bottom line model as the theoretical framework. Methodology consists of a stakeholder analysis where we conduct literature review, a consumer survey analysis, and interviews with industry experts to examine how various stakeholders elicit sustainably focused change. Essential insights made will be to understand different stakeholder actions and perspectives in relation to single-use beverage plastics, and how they contribute to creating sustainable changes in the larger context of plastic pollution control.
ContributorsGalaviz, Christopher (Author) / Wiedmer, Robert (Thesis director) / Oke, Adegoke (Committee member) / Department of Supply Chain Management (Contributor) / Dean, W.P. Carey School of Business (Contributor) / Barrett, The Honors College (Contributor)
Created2019-05
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The project goal is aimed to research the most pressing issues facing the lithium supply chain today. It then is tasked with charting a path into the future through strategic recommendations that will help reduce risk, and make a greener, cleaner, and more ethical supply chain.

ContributorsLeeson, Van (Author) / Kelman, Jonathan (Thesis director) / Wiedmer, Robert (Committee member) / Barrett, The Honors College (Contributor) / School of Sustainability (Contributor) / Department of Supply Chain Management (Contributor)
Created2022-05