This invention provides metal-foam electrodes for batteries and fuel cells. In some variations, an electrode includes a first metal layer disposed on a second metal layer, wherein the first metal layer comprises an electrically conductive, open-cell metal foam with an average cell diameter of about 25 μm or less. The structure also includes smaller pores between the cells. The electrode forms a one piece monolithic structure and allows thicker electrodes than are possible with current electrode-fabrication techniques. These electrodes are formed from an all-fluidic plating solution. The disclosed structures increase energy density in batteries and power density in fuel cells.