Manufacturing method of energy storage device

A method for manufacturing an energy storage device comprises (a) affixing a frame on a top surface of a first electrode plate; (b) affixing a glue frame outside the frame on the top surface of the first electrode plate, wherein the top surface of the glue frame is higher than the top surface of the frame; (c) filling electrolyte in a space defined by the glue frame, the frame and the first electrode plate under the vacuum environment to form a first unit; (d) mounting a second unit on the top surface of the glue frame, wherein the second unit includes a second electrode plate; and (e) affixing the second unit to the glue frame of the first unit under the vacuum environment so that the electrolyte is sealed between the first electrode plate and the second electrode plate. The invention can prevent the electrolyte from containing redundancy air, and thus increase the yield of the energy storage device.