Na2Mn1.5Fe1.5(PO4)(3) (NMFP) dandelion sphere-like particles were successfully synthesized via a hydrothermal route without addition of any templates or surfactants (laboratory and pilot scales). The hydrothermal reactor (pilot scale) is equipped with stirrer for continuous agitation of reagents during the reaction. The obtained materials were characterized by X-ray diffraction, Mossbauer spectroscopy and Scanning electron microscopy. Results show that Na2Mn1.5Fe1.5(PO4)(3) samples obtained from the reaction performed at laboratory scale have hierarchical dandelion sphere-like morphology and the dandelions consist of micro-/nano-rods. On the other hand, we obtained the self-assembly nano-rods morphology for the particles prepared using hydrothermal reactor. On the basis of the experimental results, a growth mechanism of Na2Mn1.5Fe1.5(PO4)(3) self-assembly and dandelion sphere-like particles was proposed. Temperature and time of hydrothermal reaction are found to be crucial parameters in controlling the growth of Na2Mn1.5Fe1.5(PO4)(3) particles. In addition, investigation of the effect of continuous stirring during the hydrothermal reaction shows that the reaction time can be optimized to obtain Na2Mn1.5Fe1.5(PO4)(3) with small particles size. The influence of stirring on the NMFP morphology has been clearly evidenced. Indeed, the stirring leads to homogeneous particles. Cycling studies have shown that the synthesized Na2Mn1.5Fe1.5(PO4)(3) dandelions materials exhibit specific discharge capacities of about 62 and 57 mAh g(-1) equivalent to about 1.2 and 1.05 lithium ions de-intercalated at C/15 and C/10 current density respectively.