A novel series of binuclear transition metal phthalocyanines M2Pc2HnC (M = Mn(II), Fe(II), Co(II), Ni(II), and Cu(II)) were developed for highly efficient electrocatalysts to lithium/thionyl chloride (Li/SOCl2) battery. The capacity of the battery can increase approximately by 40–65% when the binuclear compounds are present in the electrolyte of the battery. To investigate the effect of the binuclear metal phthalocyanines on Li/SOCl2 battery further, this work studied the electrocatalytic reaction of the binuclear compounds to the battery by electrochemical methods (cyclic voltammetry) and other characterization means. The results demonstrate that the order of the electrocatalytic activity of the binuclear compounds with diverse center metal ions is: Fe(II) > Co(II) > Mn(II) > Ni(II) > Cu(II).