The global transition to renewable energy and the electrification of transportation have led to an unprecedented rise in Li demand. To address the Li supply challenge, it is essential to develop more efficient extraction methods and broaden the minable Li resources. One promising solution is the use of one-dimensional (1D) olivine iron phosphate (FePO4) for electrochemical Li extraction from unconventional water sources (e.g., brines and seawater).

Although much research has focused on single-component ion insertion into FePO4, such as Li+ and Na+, the competitive ion-insertion and non-Faradaic ion-exchange within such confined structures—especially in brine-based electrolytes—remain largely unexplored. Driven by the primary goal of extracting high-purity Li from unconventional water sources to tackle the growing Li supply issue, my dissertation will first focus on optimizing the host’s lithiation response to improve Li+ selectivity and identify key features governing high structural Li+ preference. In the second part, I will delve deeper into intriguing behaviors observed surrounding mesoscopic phase evolutions at a single-particle level and solid-state ionic diffusion dynamics. My research integrates electrochemistry, materials science, and multiscale characterization techniques to address these challenges.