A method of preparing high capacity hydrous ruthenium oxide micro-ultracapacitors. A laser direct-write process deposits a film of hydrous ruthenium oxide in sulfuric acid under ambient temperature and atmospheric conditions. A dual laser process combining infrared and ultraviolet light is used for fabricating a complete wet electrochemical cell in a single processing step. Ultraviolet laser micromachining is used to tailor the shape and size of the deposited material into planar electrodes. The micro-ultracapacitors have improved size, weight, and cost efficiency and exhibit high specific power and high specific energy.