Directional ice templating for cathode and anode of lithium ion batteries
File(s)
Author(s)
Li, Guanting
Type
Thesis
Abstract
This thesis investigates the development of sustainable and scalable fabrication strategies for lithium-ion battery electrodes using Directional Ice Templating (DIT). The aim was to overcome the limitations of conventional slurry coating, particularly the use of toxic NMP solvents and the lack of microstructural control. Chapter 1 outlined the background and motivation, emphasising the importance of thick, low-tortuosity electrodes for next-generation energy storage. Chapter 2 described the materials and experimental methods, including aqueous slurry design, fabrication procedures, and characterisation techniques.Chapter 3 demonstrated the feasibility of an aqueous DIT process to fabricate NMC811 cathodes with vertically aligned structures. This architecture enhanced electronic and ionic transport kinetics while eliminating the need for NMP solvent. Surface-sensitive characterisation confirmed the chemical stability of NMC811 during aqueous processing, and electrochemical testing showed that DIT cathodes delivered higher capacities and energy densities than slurry-coated electrodes. Chapter 4 addressed scalability and developed a directional extreme supercooling process to fabricate ultra-thick electrodes with mass loadings up to 70 mg cm⁻² at large scale. A systematic calendaring study identified 30% reduction as the critical threshold for balancing vertical alignment and packing density. At this point, DIT cathodes achieved high volumetric capacity, low impedance, and superior pouch-cell energy density compared to slurry-coating controls, demonstrating industrial relevance.
Chapter 5 extended DIT to graphite anodes. Thick, free-standing DIT anodes exhibited high mass loading, excellent reversibility, and lithium-ion diffusion coefficients several orders of magnitude higher than slurry-coated electrodes, demonstrating that DIT can overcome thickness limitations on both cathode and anode sides. Together, these results establish DIT as a sustainable, scalable, and versatile electrode fabrication strategy with significant implications for high-energy-density lithium-ion batteries in electric vehicles and grid-scale storage.
Chapter 5 extended DIT to graphite anodes. Thick, free-standing DIT anodes exhibited high mass loading, excellent reversibility, and lithium-ion diffusion coefficients several orders of magnitude higher than slurry-coated electrodes, demonstrating that DIT can overcome thickness limitations on both cathode and anode sides. Together, these results establish DIT as a sustainable, scalable, and versatile electrode fabrication strategy with significant implications for high-energy-density lithium-ion batteries in electric vehicles and grid-scale storage.
Version
Open Access
Date Issued
2025-09-28
Date Awarded
01/02/2026
License URL
Advisor
Huang, Chun
Publisher Department
Department of Materials
Publisher Institution
Imperial College London
Qualification Level
Doctoral
Qualification Name
Doctor of Philosophy (PhD)