| 摘要 |
The invention discloses an olivine cathode material comprising Li, M and PO 4, having a non-stoichiometric composition wherein: —the phosphor stoichiometry PO 4:[(Li+M)/2] is between 0.940 and 1.020, —the lithium to metal ratio Li:M is between 1.040 and 1.150, and wherein M=Fe−x−z′ Mn x D z′, with 0.10<x<0.90, z′>0, D being a dopant comprising either one or both of Cr and Mg. In one embodiment PO 4:[(Li+M)/2] is between 0.960 and 1.000, resulting in an even better performing material. Performance is improved even more in another embodiment wherein PO 4:[(Li+M)/2] is less than 1.000. Improvements in performance are also obtained for either an embodiment wherein the lithium to metal ratio Li:M is between 1.070 and 1.120; or an embodiment wherein the manganese to iron ratio Mn/(Mn+Fe) is between 0.25 and 0.75; or for another embodiment wherein z′<0.05. |
