Available at: https://digitalcommons.calpoly.edu/theses/3162
Date of Award
9-2025
Degree Name
MS in Polymers and Coatings
Department/Program
Chemistry & Biochemistry
College
College of Science and Mathematics
Advisor
Shanju Zhang
Advisor Department
Chemistry & Biochemistry
Advisor College
College of Science and Mathematics
Abstract
As renewable energy sources such as wind and solar have been increasingly implemented in recent years, the demand for more advanced stationary storage backups have increased. Currently, lithium-ion batteries (LIBs) are the leading energy storage technology that provides high specific energy and power density. Functional coatings in LIBs have emerged as a transformative technology to address current battery challenges, i.e. conformal coatings for protective layers of battery components and slurry coatings for electrode manufacturing. Modern cathodes comprise a mixture of redox-active lithium particles, conductive carbon black additives, and a flexible polymer binder. Such a multicomponent electrode is structurally complex displaying porous morphology. It is evidenced that mixed ion-electron conducting polymers (MIECPs) can serve as multifunctional binders to eliminate both carbon black additives and porosity leading to enhanced device performance. In this work, we report supramolecular chemistry to synthesize liquid crystalline MIECPs as new multifunctional polymer binders. Non-covalent bonding between carboxylate poly(3-alkylthiophene)s and ionic liquid (IL) surfactants results in supramolecular MIECPs. This research utilizes a liquid crystal (LC) assembly pathway from solution to solid state to tailor charge transport nanochannels of both ions and electrons. Specifically, defect-free LC monodomains containing unidirectional alignment are obtained through mechanic shearing. Both electronic and ionic conductivities are evaluated as a function of LC alignment and a possible mechanism is proposed to interpret simultaneously
high electronic and high ionic conductivities. We believe that supramolecular MIECPs in this work serve as an advancement in binder technology, being able to serve as a multifunctional binder that exhibits superior conductivity to their counterparts, allowing for producing of high-performance batteries