Tuning a small electron polaron in FePO₄ by P-site or O-site doping based on DFT+U and KMC simulation

Abstract

Due to the existence of small polaron, the intrinsic electronic conductivity of olivine-structured LiFePO4 is quite low, limiting its performance as cathode materials for Lithium-ion batteries (LIBs). Previous studies have...

The decisive role of electrostatic interactions in transport mode and phase segregation of lithium ions in LiFePO4

“…Steady-state DFT calculations only capture one of these microscopic states. 55–58 For instance, the electron is localized on the Fe 1 or Fe 4 site for Li a and Fe 4 or Fe 7 site for Li b due to the minimum Li + –e − (Fe 2+ ) distance, d Fe 1 –Li a = d Fe 4 –Li a = d Fe 4 –Li b = d Fe 7 –Li b = 3.317 Å (Fig. 3a).…”

“…Steady-state DFT calculations only capture one of these microscopic states. [55][56][57][58] For instance, the electron is localized on the Fe 1 or Fe 4 site for Li a and Fe 4 or Fe 7 site for Li b due to the minimum Li + -e − (Fe 2+ ) distance, d 3a). Nevertheless, when the electron is localized on the Fe 4 site, it may not transfer during Li + hopping from site a to site b.…”