Understanding how phase composition and nanoscale architecture govern charge-storage behavior is essential for advancing next-generation anodes. In this study, we explain the structure¿electrochemistry relationship in sodium titanates by comparing pristine hydrated nanosheets (NaTiNS) with a calcined, mixed-phase (Na2Ti6O13/Na2Ti3O7) structures. Using a comprehensive suite of techniques¿including X-ray diffraction with Rietveld refinement, Raman and FTIR spectroscopy, thermogravimetric analysis, and high-resolution TEM¿we map the collapse of the laminar titanate structure. This study focuses on the resulting electrochemical and kinetic dynamics. Using advanced electroanalytical techniques such as three dimensional Bode mapping and impedance-derived analyses. We analyze the real-time evolution of solid electrolyte interphase (SEI) formation, charge-transfer resistance, and diffusion-controlled processes. We demonstrate that structural water in the pristine phase acts as an interlayer spacer, facilitating diffusion-controlled bulk intercalation and yielding a high initial specific capacity of 208.6 mAh g¿1, excellent reversibility, and battery-like behavior. While the calcined phase-mixed structure delivers a significantly lower initial capacity of 110.2 mAh g¿1, displays pseudocapacitive signatures and enhanced stability at high rates. These multidimensional insights expose distinct degradation pathways and activation phenomena that remain hidden in conventional electrochemical testing. Ultimately, this work highlights how phase engineering can effectively set the electrochemical kinetic limits and energy storage mechanisms of structurally robust, low-cost titanate anodes.
