Thangadurai, VenkataramanZhou, Chengtian2021-09-022021-09-022021-08-26Zhou, C. (2021). Designing Electrolytes and Electrode-electrolyte Interfaces for Next-Generation Lithium Metal Batteries (Doctoral thesis, University of Calgary, Calgary, Canada). Retrieved from https://prism.ucalgary.ca.http://hdl.handle.net/1880/113804State-of-the-art lithium-ion batteries (LIBs) are approaching their energy density limits and thus may not be the answer to the ever-increasing demand for higher specific energy density in today’s energy storage and power applications. Li metal is considered the ultimate anode material due to its ultra-high specific capacity 3860 mAh g-1, more than 10 times higher than lithiated graphite. Solid-state electrolytes (SSEs) provide a potential solution to advance the performance of Li metal batteries (LMBs). However, the device integration of SSEs, especially Li-stuffed garnet, is exceptionally challenging. Another critical aspect for LMBs is to limit excess Li metal at the anode. In this thesis, the interface between Li metal anode and Li-stuffed garnet Li6.5La2.9Ba0.1Zr0.4Ta1.6O12 is investigated. Poor contact between Li and garnet is identified as the reason for high interfacial resistance. A viable surfactant-assisted wet chemical method to deposit ZnO layer on Li-stuffed garnet is reported to reduce the interfacial resistance to as low as 10 Ω cm2. A composite polymer-ceramic electrolyte (CPE) for room temperature solid-state Li-S battery (SSLSB) is demonstrated. The CPE has low interfacial resistance against both Li metal anode and sulfur cathode. An engineered sulfur-Ketjen black(S@KB) composite cathode is coupled with CPE to demonstrate a SSLSB with a pronounced specific capacity of 1108 mAh g−1 and areal capacity of 1.77 mAh cm−2. As CPE is prepared by a solution casting method, lean solvent confinement affects the morphological structure and ionic conductivity of CPE. A higher amount of solvent retention leads to higher ionic conductivity but at the cost of membranes’ mechanical properties. In order to study anode-free Li-metal batteries (AFLMBs), a special coin cell configuration is designed with high compression. The high pressure leads to more stable cycling performance, providing a more accurate assessment of AFLMBs. A carbonate-glyme hybrid electrolyte for AFLMB is demonstrated with capacity retention of 73% for 50 cycles. The hybrid electrolyte possesses a unique solvation structure, where diglyme solvates both Li-ions and film-forming additive, while carbonates dilute the mixture, enabling facile ion migrations.engUniversity of Calgary graduate students retain copyright ownership and moral rights for their thesis. You may use this material in any way that is permitted by the Copyright Act or through licensing that has been assigned to the document. For uses that are not allowable under copyright legislation or licensing, you are required to seek permission.Lithium Metal BatteriesEducation--Sciencesdoctoral thesis10.11575/PRISM/39149