Corrosion behavior of niobium current leads of fluorocarbon-lithium cells are studied. Polarization measurements at plain niobium leads and at such leads in a contact with fluorocarbon cathode in an electrolyte of fluorocarbon-lithium cell were carried out. Besides, behavior of niobium lead directly in a feedthrough of real cells was studied. The contact of niobium with fluorocarbon cathode is shown to result in toughening of corrosion conditions and in possible niobium depassivation.