NOVELTY - A fuel cell has electric-power-generation portion (100) with acid medium and basic medium in which electrodes are arranged, container (400), electric-power-generation contribution substance storage portion (200) with reacting-material storage portion (210), and electric-power-generation contribution substance transport unit (500) with reacting-material transport unit (510) and electric-power-generation substance supply port (110).    USE - For portable devices .    ADVANTAGE - The fuel cell is simple and enables safe generation of electric power. Stable electromotive force is exhibited.    DETAILED DESCRIPTION - A fuel cell has electric-power-generation portion (100), container which can be attached or detached from battery mainframe (700) equipped with electric-power-generation contribution substance storage portion (200) and electric-power-generation contribution substance transport unit (500), and electric-power-generation contribution substance supply port. The portion (100) is equipped with acid medium in which electrode (I) is arranged and basic medium in which electrode (II) is arranged. The acid medium and basic medium are mutually adjoined. The acid medium and/or basic medium contain reacting material. The storage portion (200) is equipped with reacting-material storage portion (210). The supply port (110) is equipped with reacting-material supply port (111). The transport unit (500) is equipped with reacting-material transport unit (510) which supplies the reacting material from storage portion (210) to portion (100) through the supply port (111).    DESCRIPTION OF DRAWING(S) - The figure shows the explanatory drawing of structure of the fuel cell. (Drawing includes non-English language text).    electric-power-generation portion (100)    electric-power-generation contribution substance supply port (110)    acid medium supply port (112)    basic medium supply port (113)    product discharge portion (120)    electric-power-generation contribution substance storage portion (200)    reacting material storage portion (210)    acid medium storage portion (221)    basic medium storage portion (222)    product recovery portion (300)    container (400)    electric-power-generation contribution substance transport unit (500)    reacting material transport unit (510)    acid medium transport unit (520)    basic medium transport unit (530)    product transport unit(700) battery mainframe (600)