The present invention relates to a device for an electrochemical cell, comprising a first layer of substrate material having a plurality of first hydrophilic areas of the substrate and at least one hydrophobic area separating said first hydrophilic areas, the first layer of substrate material comprising at least two first electrodes made on at least two first hydrophilic areas; a second layer of substrate material having a plurality of second hydrophilic areas of the substrate and at least one hydrophobic area separating said second hydrophilic areas, the second layer of substrate material comprising at least two second electrodes made on at least two second hydrophilic areas; and one or more electrical conductors connected to at least two of said first electrodes. The first layer of substrate material and the second layer of substrate material are positioned on top of one another such that the at least two first electrodes are aligned with the at least two second electrodes in order to form at least two electrochemical cells for producing voltage when the at least two hydrophilic areas are contacted with an aqueous liquid.