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The data obtained by thermogravimetry (TG), differential thermal analysis (DTA), and X-ray diffraction (XRD) measurements of the stoichiometric mixture of LiNO, NHVO, and NHHPO were analyzed by both the Flynn-Wall-Ozawa (FWO) and Friedman-Reich-Levi (FRL) methods. The whole solid state reaction process could be divided into four stages corresponding to α values of 0.03-0.20, 0.30-0.60, 0.70-0.80, and 0.90-0.99. The nucleation of LiVPO (α = 0.70-0.80) is a determining step of the four-reaction processes, for which the mechanism of random nucleation and subsequent growth, described by the Avrami-Erofeev equation (n = 4) G(α) = [-ln(1 - α)], was assumed. Moreover, the Gibbs free energy of activation ΔG*, enthalpy of activation ΔH*, and entropy of activation ΔS* at maximum temperature of the peak for the determining step were 99.24 kJ·mol, 199.97 kJ·mol, and 136.30 J·mol·K, respectively. Finally, XRD analyses confirmed that the LiV(PO) synthesized by the precursor route is a pure phase.

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