Theoretical studies of the dissociation of Mn atoms on different crystal surfaces of LiMn0.5Fe0.5PO4

LiMn1-xFexPO4 (LMFP) has become one of the most popular cathodes in lithium-ion batteries (LIB) for the applications of electric vehicles. However, the dissolution of Mn in LMFP is one of the known drawbacks to weaken the performance of LIB, and its detailed mechanism remains unclear. Here, we have evaluated the ability to dissociate Mn on different crystal surfaces of LiMn0.5Fe0.5PO4 by first-principles calculations and revealed a relationship between the different crystal surfaces of LiMn0.5Fe0.5PO4 and Mn dissolution. Analyses of the dissociation process show that the (001) surface of LiMn0.5Fe0.5PO4 is most likely to lose Mn. Conversely, the higher dissociation energy on the (010) surface proves that the Mn is more difficult to dissociate. The results of this work are essential for the mechanism of Mn dissociation on different surfaces of LiMn0.5Fe0.5PO4 and the development of lithium-ion batteries.