Date of Award:

8-2024

Document Type:

Dissertation

Degree Name:

Doctor of Philosophy (PhD)

Department:

Chemistry and Biochemistry

Committee Chair(s)

Gang Li

Committee

Gang Li

Committee

Bradley S. Davidson

Committee

Ryan Jackson

Committee

Lance C. Seefeldt

Committee

Kang Xu

Abstract

Our current energy policy relies heavily on burning fossil fuels, raising serious concerns due to CO2-related global warming. Consequently, significant progress is being made in pursuing renewable and green energy sources, such as solar, wind, and geothermal energy. These renewable energies require rechargeable batteries as energy storage systems to compensate for their intermittent nature.

Over the decades, lithium-ion batteries (LIBs) have become the dominant power sources for portable electronic devices. Current LIBs rely on graphite anodes with a limited theoretical capacity (372 mAh g-1), which restricts their advanced applications. Li metal (Li0) anodes, with the highest theoretical capacity (3860 mAh g-1), are considered the "Holy Grail" for developing high-energy-density battery systems.

My research primarily focuses on lithium metal batteries (LMBs) and anode-free lithium metal batteries (AFLMBs). In LMBs, Li0 is directly used as the anode while in AFLMBs, the Li0 anode is replaced with a copper (Cu) foil which serves as the current collector to support Li0 plating/stripping. All the Li+ in AFLMBs comes from the lithiated cathode. The configuration of AFLMB has gained significant attention due to its potential for maximum energy and improved safety.

However, the high reactivity of Li0 poses significant challenges for developing practical LMBs and stable AFLMBs. Functional electrolyte design is considered a crucial strategy to promote their development via generating a stable and protective interphase on the Li0 surface. During my Ph.D. studies, two lithium additive-based electrolyte systems were designed and studied for LMBs and AFLMBs, respectively. Comprehensive studies of the physiochemical and electrochemical performances of the designed electrolytes and battery systems were conducted, revealing detailed electrode and electrolyte interphase chemistry through spectroscopy studies.

Beyond LMBs and AFLMBs, zinc metal batteries (ZMBs) offer a promising alternative energy storage system due to the advantages of the Zn metal anode, such as high volumetric capacity, intrinsic safety, and abundance. An advanced and novel non-aqueous Zn electrolyte was discovered for ZMBs. Systematic electrochemical tests were conducted to demonstrate its feasibility and stability. This work provides new insights and opportunities for the future development of high-performance non-aqueous ZMBs.

Checksum

aba617814cdb3355e347c7fb930ec92e

Download

Share

COinS

Copyright for this work is retained by the student. If you have any questions regarding the inclusion of this work in the Digital Commons, please email us at .