Study of Li⁺ Transport Processes in LiMPO₄ Battery Materials (M = transition metal)
The commercial success of LiFePO₄ in high-power Li-ion batteries is greatly associated to its ultrahigh-rate charge/discharge performance. Since Li1–xFePO₄ (0.05 ≤ x ≤ 0.95) separates into two phases with poor electronic and ionic conduction, this raises questions regarding the structural dynamics of phase separation. Considering LiFePO4 as a model structure with its outstanding stability, a higher energy density material is achieved by the incorporation of high operating potential transition metals into the structure. The challenge here is to understand the exact Li⁺ transport mechanism engendered by the modified crystalline structure where the effects have a direct impact on the dynamics of de/lithiation process. Powder X-ray diffraction (PXRD), ⁶,⁷Li nuclear magnetic resonance (MAS NMR) and attenuated total reflectance infrared spectroscopy (ATR-IR) are employed to detect structural information.
Study of Ionic transport in LTO Anode Material
Li-ion battery’s limited power represents a barrier for their application in the domain of renewable energy. For high power applications, the limitation in the Li⁺ transport through the electrolyte present inside the pores of the composite electrode must overcome. This project aims to study the ionic transport limitations in a (Li₄Ti₅O₁₂) film using scanning ion conductance microscopy, which is traditionally used as a topographic technique in the scientific community. Numerical simulations help to understand more about the current response in SICM with respect to the probe dimensions.