Imaging state of charge and its correlation to interaction variation in an LiMn_0.75Fe_0.25PO₄ nanorods–graphene hybrid

Visualization of the state of charge (SOC) in an LiMn_0.75Fe_0.25PO₄ nanorods–graphene hybrid nanostructure (LMFP–C) is realized by chemical mapping of the Fe valance state using scanning transmission X-ray microscopy (STXM). The LMFP–graphene interaction strength variation studied by C K-edge STXM has been correlated to SOC variation, i.e. a stronger interaction was observed for sample regions with a higher SOC in LMFP. Such structure–performance correlation opens new perspectives for a rational design of a better performance olivine cathode for lithium ion batteries.