Work of running double-chamber electrochemical reactor is investigational for an electrosynthesis Ni(OH)2. It is shown that the basic parameter of the mode is a relative current is attitude of current of I toward the theoretical equivalent current of I*, at that fully initial reagents are expended in a reactor. Mode of I/I* = 1 differentiates two areas (I < I* and I > I*) with salutatory and like changing physical and chemical and electrochemical properties Ni(OH)2.