Flexible energy storage device as the functional unit of wearable electronics presents glorious application prospects. In this work, the growth of fractal structure dendrites as a fibrous matrix of electrode in energy storage device is regulated by electrochemical deposition to seek a novel way for the resource utilization of metal dendrites in electrolysis industry. Then the micro-nano scale assembling on electrode is realized by integrating micro metal arrays with Ni(OH)(2) and Fe2O3 nanosheets. The highly fractal structure of iron dendrite provides more nucleation sites for the assembling of Fe2O3 nanosheets, which contributes to improving specific capacitance about 2166 mF cm(-2) (specific capacity of 0.6 mA h cm(-2)) at 1 mA cm(-2), cycle stability and other characteristics of the device. Then, an energy storage device is fabricated by utilizing Ni(OH)(2)@Ni dendrite matrix as positive electrode and Fe2O3@Fe dendrite matrix as negative electrode, which demonstrates excellent energy density (0.17 mWh cm(-2)) at the power density (0.8 mW cm(-2)) in the gel electrolyte. Simultaneously, a lot of fibrous energy storage devices can be used to weave the flexible functional fabric, achieving the greater integration of energy. (c) 2019 The Electrochemical Society.