A power source for a micro-device is provided. The power source may include a cup, a lid and electrolytes. The cup may be formed of a hard metal material and walls of the cup may define a cavity. An opening in the cup may provide access to the cavity and a surface of the cavity may be deposited with one of an anode or cathode material. The lid may be formed of a hard metal material, the lid may cooperate with the cup to fit into the opening closing off the cavity. The cavity may be coated with the other of the anode or cathode material. Electrolytes may be contained in the cavity.