The utilization of an olivine structured material as positive electrode material was pioneered by the group of Goodenough in 1974. This material class exhibits the general formula of AMXO 4 , the A site mostly being occupied by Li, although the intercalation of other alkali metal ions has been studied as well. The transition metal site is most popularily occupied by Fe, Mn, Co or Ni, while X typically equals P, less often Si or Ge. From a geometric point of view, the olivine structure consists of MO 6 octahedra, that are connected to two LiO 6 octahedra and one XO 4 tetrahedra via shared edges. Its crystal structure is depicted in Figure .