NOVELTY - An electrochemical cell system (10) comprises electrochemical cell stack(s) (100) having a cathode inlet (120); a blower (150) having a blower outlet (155) in fluid communication with the cathode inlet for providing an oxidant fluid; and a control unit (200) for regulating the system. An electrical power supply (160) is connected to the blower, and the electrical power supply is controlled by the control unit to operate the blower intermittently, for a first blower operating period, a following period of non-operation of the blower and following further blower operating period.    USE - An electrochemical cell system, preferably fuel cell power module.    ADVANTAGE - The electrochemical cell system can provide freeze shutdown of a power module or other electrochemical cell stack that removes a sufficient amount of water from the cells but does not utilize too high a blast pressure.    DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for a method of operating an electrochemical cell system comprising:    (A) electrically connecting a power supply to an oxidant process fluid blower of the cell system;    (B) opening oxidant fluid valve of the cell system;    (C) operating the blower by switching the power supply on, to create an oxidant fluid flow through process fluid conduits of the peripheral devices and through a cathode of the electrochemical cell stack during a first blower operating period;    (D) stopping operation of the blower during a first period of non-operation of the blower; and    (E) operating the blower during further blower operating period; and where there are at least two further blower operating periods, providing a further period of non-operation of the blower between consecutive further blower operating periods.    DESCRIPTION OF DRAWING(S) - The drawing shows a schematic view of an electrochemical cell system.    Electrochemical cell system (10)    Electrochemical cell stack (100)    Cathode inlet (120)    Blower (150)    Blower outlet (155)    Electrical power supply (160)    Control unit (200)