Further, as the solvent used in the solution B, at least one or more kinds selected from the ether-based solvents, ketone-based solvents, ester-based solvents, alcohol-based solvents, and amine-based solvents are used. In these solvents, the complexes between the polycyclic aromatic compounds and the lithium may be stably present instantaneously or sustainably, and the lithium is mildly desorbed from the silicon compound. In particular, from results of Examples 1-1 to Examples 1-7, it is found that the ether-based solvents are desirably used.

Further, the concentration of the polycyclic aromatic compound in the solution B is preferably between 10^?2 mol/L to 5 mol/L, and particularly preferably between from 10¹ mol/L to 3 mol/L. Compared with the case where the concentration of the polycyclic aromatic compound is smaller than 10^?2 mol/L like in Example 1-8, in the case where the concentration of the polycyclic aromatic compound is not smaller than 10^?2 mol/L and not larger than 5 mol/L (for example, Examples 1-1 and 1-3), the retention rates and the initial efficiencies are improved. This is because the lithium is more efficiently desorbed from the silicon compound. Further, compared with the case where the concentration of the polycyclic aromatic compound exceeds 5 mol/L like in Example 1-11, in the case where the concentration of the polycyclic aromatic compound is not smaller than 10^?2 mol/L and not larger than 5 mol/L, the retention rate and the initial efficiency are improved. This is because when the negative electrode active material is formed into the non-aqueous electrolyte secondary battery, the reaction residue is not eluted into the electrolytic solution and the battery characteristics may be suppressed from deteriorating due to the side reaction.