NOVELTY - Shutdown and self-maintenance operation process of liquid fuel cell system (100) comprises e.g.: providing shutdown signal to liquid fuel cell system, and liquid fuel cell (102) of liquid fuel cell system stops discharging by receiving shutdown signal, where (a) liquid fuel cell system stops supplying cathode gas, (b) after first duration, liquid fuel cell system starts supplying cathode gas, and (c) liquid fuel cell starts discharging until output power of liquid fuel cell is less than or equal to first predetermined value.    USE - The process is useful for shutdown and self-maintenance operation.    DETAILED DESCRIPTION - Shutdown and self-maintenance operation process of a liquid fuel cell system (100) comprises: providing a shutdown signal to the liquid fuel cell system, and a liquid fuel cell (102) of the liquid fuel cell system stops discharging by receiving the shutdown signal, where (a) the liquid fuel cell system stops supplying a cathode gas, (b) after a first duration, the liquid fuel cell system starts supplying the cathode gas, (c) the liquid fuel cell starts discharging until an output power of the liquid fuel cell is less than or equal to a first predetermined value, (d) the liquid fuel cell stops discharging and the liquid fuel cell system stops supplying the cathode gas, a duration between starting supply of the cathode gas at step (b) and stopping supply of the cathode gas at step (d) is a second duration, repeating steps (a)-(d) and stopping the liquid fuel cell system completely. An INDEPENDENT CLAIM is also included for shutdown and self-maintenance operation process (I) of liquid fuel cell system, comprising giving shutdown signal to the liquid fuel cell system, when the liquid fuel cell system receives the shutdown signal, liquid fuel cell of the liquid fuel cell system stops discharging, and stops supplying an anode fuel, where (a1) supply of a cathode gas is stopped for a first duration, (b1) starting supply of the cathode gas for a second duration, repeating steps (a1)-(b1), and stopping the liquid fuel cell system completely.    DESCRIPTION OF DRAWING(S) - The figure shows a schematic view of a liquid fuel cell system.    Liquid fuel cell system (100)    Liquid fuel cell (102)    Cathode gas supply device (104)    Control unit (106)