In recent years, metallic tin and tin compounds have proven to be interesting electrode materials for lithium batteries. However, detailed information about the mechanism of reaction in phosphate compounds is needed to improve the performance of some previously examined and future electrode materials containing these species. In the present work, powerful techniques for the study of the local environments of the atoms, such as Sn-119 Mossbauer spectrometry and Li-7 and P-31 MAS NMR, are used to obtain basic information on the processes involved during the discharge/reduction of the electrode material. The results allow extracting valuable information about the possible interactions between the participating atoms and the surrounding framework.