A miniaturized electrochemical cell and a method for making it are provided. The method includes preparing at least one inner electrode of an electron conducting or semi-conducting material M1; providing a hollow support made of an electrically insulating material M6 and having at least one internal hollow channel; depositing on the external surface of the support a layer of an electrically conducting material M2; forming a template of colloidal particles of an electrically insulating material M3, on the M2 layer; depositing a layer of an electrically conducting material M4 on the M2 layer; depositing a layer L1 of an electron conducting or semi-conducting material M5 on the M4 layer, introducing the at least one inner electrode into the at least one internal hollow channel of the obtained structure; stabilizing the structure at its two open ends with an electrically insulating material M7; and removing M2, M3, M4 and M6 materials.