Journal of The Electrochemical Society, 159 (1) A55-A59 (2012) A55 0013-4651/2012/159(1)/A55/5/$28.00 © The Electrochemical Society The Effect of Particle Size on Phase Stability

The effect of particle size on the phase stability of delithiated LixMnPO4 (x < 1) is elucidated using temperature-controlled in situ X-ray diffraction (XRD). The phase transformation of LixMnPO4 (x < 1) at high temperature was apparently altered by the particle size. While LixMnPO4 phase having large particle size (ca. 200 nm to 1 μm) decomposed into Mn2P2O7 at the temperature between 200◦C and 250◦C, consistent with previous studies, phase transformation into Mn3(PO4)2 was observed at the same temperature when the delithiated LixMnPO4 phase had a small particle size (ca. 50 nm). This indicates that the phase transformation of a LiMnPO4-based battery may vary with particle size