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Adsorption

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Description: BACKGROUND 1. Technical Field The present disclosure relates to the field of energy storage. In particular, the present disclosure is directed to an energy storage device that includes a pressure chamber containing a porous material that adsorbs air. 2. Description of the Related Art Compressed air energy storage is commonly known by its acronym "CAES." In some CAES devices, the air compressor is driven by an electric motor, and subsequently used to drive an air motor or turbine connected to an electromagnetic generator,thereby forming the functional equivalent of an electrochemical battery. If the charge-discharge cycle is carried out slowly enough to be approximately isothermal, meaning that the heat generated by compression dissipates without raising the temperatureof the air appreciably during compression, and the heat drawn in from the environment likewise keeps the air from cooling appreciably during expansion, this form of electricity storage can have good efficiency. CAES systems can also be engineered to have higher reliability, lower maintenance and longer operating lifetimes than chemical batteries, and their cost can be comparable to battery-based systems providing that an inexpensive means of storingthe compressed air is available. Unfortunately, the high cost, weight and large size of manufactured pressure vessels in which to store the air, such as steel tanks, prevents CAES devices from competing with batteries in all of their usual applications. To date CAES has been used for three commercial purposes. The first and most widespread use is not as a means of energy storage per se, but to power pneumatic tools and machines in shops and factories. Pneumatic tools have higherweight-to-power ratios than electrically powered tools, and the small electric motors in such tools also tend to be inefficient compared to the larger motors that drive air compressors. The compressed air is stored in a tank big enough to serve as abuffer and ensure that the p