During reversible ion insertion, intercalation material lattices undergo structural changes, resulting in strains and volume change that lead to structural degradation and cycle limitations. Inspired by shape-memory alloys, which undergo substantial lattice transformations while maintaining minimal macroscopic volume changes or internal stress, I develop a theoretical framework for forecasting structural transformation in intercalation compounds. This framework highlights design principles to create microstructures resembling shape-memory characteristics in intercalation materials.
After evaluating 5,000 pairs of compounds, the findings suggest that Spinel LixMn2O4 (LMO) is a promising candidate, emphasizing a direct correlation between structural transformations, microstructures, and enhanced capacity retention in these materials. In summary, designing intercalation materials with customized crystallographic characteristics offers a promising approach to discovering compounds that maintain their performance over extended use.
Multiscale phase-field modeling
From the previous crystallographic design, I analytically construct the twin microstructure of Spinel LMO. However, the microstructural evolution pathways under dynamic discharge conditions for Spinel LMO remain unclear. To address this gap, I establish a continuum mechanics model that delves into the intricate relationship between diffusion and finite lattice deformation in phase transformation materials. This framework is adapted to intercalation materials, specifically Spinel LMO, enabling an investigation into the delicate interplay between Li-diffusion and the cubic-to-tetragonal deformation of lattices.
Buckling analysis for thin-walled structures