![]() While the large-scale production of CFs from natural lignocellulosic biomass and their applications in sports equipment have not yet been realized, CFs still provide a promising market prospect as green and low-cost materials. The importance and application of CFs in sports equipment manufacturing are briefly summarized. Recent strategies to further improve the quality of such CFs are discussed. The influence of the properties, advantages, separation, and extraction of lignin and cellulose (the most abundant natural biopolymers), as well as the spinning process on the final CF performance are detailed. This review focuses on the latest research on the conversion of natural lignocellulosic biomass into precursor fibers and CFs. However, the high costs and environmental problems of the production process prompted the development of new precursors from natural biopolymers. The latter depends on fast faraday redox reaction.At present, high-performance carbon fibers (CFs) are mainly produced from petroleum-based materials. Its capacitance is proportional to the specific surface areas of electrode material. The former depends on the mechanism of double layers, which is result of the separation of charges at interface between the electrode surface of active carbon or carbon fiber and electrolytic solution. Usually super capacitors are divided into two types: Left: "normal" capacitor, middle: electrolytic, right: electric double-layer capacitor Comparison of construction diagrams of three capacitors. The electrolyte supplies and conducts the ions from one electrode to the other. The two electrodes are separated by a membrane, which allows the mobility of charged ions and forbids no electronic contact. On the electrodes, current collectors with a high conducting part assure the interface between the electrodes and the connections of the super capacitor. The two electrodes, made of activated carbon provide a high surface area part, defining so energy density of the component. Super capacitors are constituted of two electrodes, a separator and an electrolyte. The amount of stored energy is function of the available electrode and electrolyte surface, the size of the ions, and the level of the electrolyte decomposition voltage. Super capacitor is a double layer capacitor the energy is stored by charge transfer at the boundary between electrode and electrolyte. The amount of current needed to charge the capacitor is determined by the following equation: The magnitude of voltage where charges begin to flow is where the electrolyte begins to break down. The electric double layer formed becomes an insulator until a large enough voltage is applied and current begins to flow. The activated carbon fiber electrodes are impregnated with an electrolyte where positive and negative charges are formed between the electrodes and the impregnant. The charging/discharging occurs in an ion absorption layer formed on the electrodes of activated carbon. This large surface area allows for the absorption of a large amount of ions. ![]() The surface area of the activated carbon layer is extremely large yielding several thousands of square meters per gram. The thickness of the electric double layer is as thin as a molecule. Super capacitors do not have a traditional dielectric material like ceramic, polymer films or aluminum oxide to separate the electrodes, but instead have a physical barrier made from activated carbon that when an electrical charge is applied to the material a double electric field is generated which acts like a dielectric. The dielectric not only separates the electrodes, but also has electrical properties that affect the performance of a capacitor. Capacitors consist of 2 metal electrodes separated by a dielectric material.
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