Some variations provide an electrochemical solid-state field-emission ion source comprising: (a) an ion conductor comprising a protuberance within a protuberance region, wherein the ion conductor contains mobile ions; (b) a first electrode disposed distally from the ion conductor, wherein the protuberance region is on the same side of the first electrode as the ion conductor; (c) a second electrode in contact with the ion conductor, wherein the second electrode is electrically isolated from the first electrode; and (d) an electrical insulator between the ion conductor and the first electrode. Some variations provide a method of electrochemically emitting ions from a field-emission ion source, comprising: applying an electrode potential between the first electrode and the second electrode; oxidizing or reducing the atoms in the atom reservoir, and transporting the atoms into and through the ion conductor as mobile ions; and emitting the mobile ions from the protuberance.