A method of supplying a fuel cell a power supply phases of alternating purge and

Disclosed is a method for supplying a fuel cell in reactive species, comprising a stack of electrochemical cells divided into N distinct groups, wherein: performing a plurality of selective feeding steps of the N groups ( a, B) of cells reactive species, as a result of each of the feed steps, is carried out a purge step of the N groups (a, B) of cells.