▎ 摘　　要

NOVELTY - Porous carbon-based film (100) including a porous carbon-based matrix (102) comprises (a) yolk-shell type structures, where each yolk-shell type structure comprises an elemental sulfur nanostructure (104) positioned within a hollow space (106) of the porous carbon-based matrix and (b) graphene structures (108) attached to the porous carbon-based matrix. USE - The film is used in electrode of an energy storage device, preferably a rechargeable battery (all claimed). The film is used in fuel cells, capacitors (supercapacitors, electrochemical capacitors, variable capacitors or ultracapacitors), other battery cell, system or pack technology, optical applications, controlled release applications, secondary lithium ion or lithium-sulfur batteries, and in articles (e.g. virtual reality device, an augmented reality device, a fixture that requires flexibility such as an adjustable mounted wireless headset and ear buds, a communication helmet with curvatures, a medical patch, a flexible identification card, a flexible sporting good and a packaging material). ADVANTAGE - The film enhances the electrochemical properties of lithium-sulfur energy storage system, increases battery cyclability, is binder-free, safe and economical, has improved flux for mass transfer, improved electric conductivity, and enhanced electrochemical properties, provides high adsorption of sulfur, has excellent mechanical strength and minimizes the diffusion distances to the interior surfaces hence promotes fast charge-discharge of supercapacitors. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are included for the following: (1) an energy storage device; and (2) a method for making the porous carbon-based film. DESCRIPTION OF DRAWING(S) - The drawing shows a cross-sectional view of porous carbon-based film including a single yolk-shell structure. Porous carbon-based film (100) Porous carbon-based matrix (102) Elemental sulfur nanostructure (104) Hollow space (106) Graphene structure (108)