Abstract: This invention relates to an electrochemical cell comprising an anode structure comprising an element selected from the group consisting of group 1, group 2, group 8, group 12 and group 13 of the Periodic Table of Elements; a cathode structure comprising a catalyst; and a hydrogel located between the anode structure and the cathode structure. In a preferred embodiment, the cell comprises the anode of Zinc, the catalyst of CoOx/C, the hydrogel of free-standing alkaline polyacrylamide hydrogel, wherein said hydrogel was first synthesized via UV-initiated radical polymerization of acrylamides, followed by exchange of water with an alkaline electrolyte of potassium hydroxide (KOH). The invention further relates to a method of manufacturing such an electrochemical cell and the use of a hydrogel in a metal/air battery.