INVESTIGATION OF POLYETHER AND POLYETHER COMPOSITES AS ELECTROLYTES FOR ADVANCEMENT TOWARDS LITHIUM METAL BATTERIES
Epoxides, polyether precursors, are favorable materials for many applications. They have a ring strain that promotes polymerization, diverse functionalities, and are relatively easy to synthesize through sustainable means. Although epoxide polymerization can be traced back a few decades, it wasn’t until 2017, when published work by Ferrier reported using mono(μ-alkoxo)bis(alkylaluminum) (MOB) to quickly and easily polymerize different epoxides. This polymerization platform will be used to explore polyether-based single-ion conductor electrolytes in the first work. Polymer electrolytes are said to be the future for lithium batteries. By replacing the anodic materials with solid lithium (making a lithium metal battery) and the organic solvent media with a polymer, the high functioning lithium metal’s properties will increase battery efficiency. This project will dive into utilizing poly(epichlorhydrin) (PECH) and poly(propylene oxide) (PPO) to synthesize a single-ion conducting electrolyte. This work reveals synthesis of the single-ion conductor (SIC) using bis(trifluoromethanesulfanamide) as the single-ion conducting moiety. The incorporation of PPO combats the crystallinity of PECH, which is shown by Tg analysis and ionic conductivity. The knowledge gained from this research will be valuable in moving forward for solid state electrolytes for lithium metal battery applications.Polymer composites are currently the most popular way to advance electrolyte matrices within lithium batteries, as they can eliminate the adverse properties of polymers (i.e. crystallinity and low ionic conductivity) by employing filler (solvents, ceramics, carbon powders, etc.) materials within the matrix to improve properties for desired applications. With intentions to incorporate the previous project, this work focuses on utilizing polyether-grafted nanoparticles (NPs) incorporated in a polyether matrix to study ether composites for LMB applications. An initiator was grafted onto the surface of the NPs and ECH was polymerized from the site. We alleviate compatibility concerns by using a low molecular weight ether matrix with a high molecular weight ether filler as well as explore possible electrolyte applications and combinations with the ether SIC. The final project is intended to further epoxide use and application by expanding possible polymerization methods inspired by MOB synthesis. This work utilizes primary and secondary amine compounds to synthesize polymerization platforms. This introductory study revealed simplistic synthesis of different amine initiators that could be used in tandem with the N-Al adduct to polymerize epoxides with different functionalities. These platforms will be utilized to explore different pathways for synthesizing polymer and composite electrolytes for lithium battery applications.
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- In Collections
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Electronic Theses & Dissertations
- Copyright Status
- In Copyright
- Material Type
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Theses
- Authors
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Crum-Dacon, Shaylynn
- Thesis Advisors
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Ferrier, Robert
- Committee Members
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Cheng, Shiwang
Hickey, David
Swain, Greg
- Date
- 2023
- Subjects
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Chemical engineering
Polymers
Chemistry
- Program of Study
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Chemical Engineering - Doctor of Philosophy
- Degree Level
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Doctoral
- Language
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English
- Pages
- 109 pages
- Permalink
- https://doi.org/doi:10.25335/4yq3-3k90