Premium
Isolation of Solid Solution Phases in Size‐Controlled Li x FePO 4 at Room Temperature
Author(s) -
Kobayashi Genki,
Nishimura Shinichi,
Park MinSik,
Kanno Ryoji,
Yashima Masatomo,
Ida Takashi,
Yamada Atsuo
Publication year - 2009
Publication title -
advanced functional materials
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 6.069
H-Index - 322
eISSN - 1616-3028
pISSN - 1616-301X
DOI - 10.1002/adfm.200801522
Subject(s) - solid solution , materials science , phase diagram , miscibility , electrochemistry , thermodynamics , ion , lithium (medication) , solid state , phase (matter) , chemical engineering , nanotechnology , electrode , engineering physics , chemistry , polymer , composite material , metallurgy , medicine , physics , organic chemistry , quantum mechanics , endocrinology , engineering
State‐of‐the‐art LiFePO 4 technology has now opened the door for lithium ion batteries to take their place in large‐scale applications such as plug‐in hybrid vehicles. A high level of safety, significant cost reduction, and huge power generation are on the verge of being guaranteed for the most advanced energy storage system. The room‐temperature phase diagram is essential to understand the facile electrode reaction of Li x FePO 4 (0 < x < 1), but it has not been fully understood. Here, intermediate solid solution phases close to x = 0 and x = 1 have been isolated at room temperature. Size‐dependent modification of the phase diagram, as well as the systematic variation of lattice parameters inside the solid‐solution compositional domain closely related to the electrochemical redox potential, are demonstrated. These experimental results reveal that the excess capacity that has been observed above and below the two‐phase equilibrium potential is largely due to the bulk solid solution, and thus support the size‐dependent miscibility gap model.