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Significant contribution to specific capacitance is possible from fast faradaic reactions at the electrode-electrolyte interface in addition to the electric double layer effect. Thus for nanoprous (activated) carbon based electrodes a specific capacitance up to 200-220 F/g is mentioned for organic electrolyte, whereas for aqueous electrolyte, the value is limited to 400-500 F/g. A specific capacitance and a specific energy are seldom revealed as the main result of the performed investigation. Many reported results refer to nanostructured carbon based materials and the related composites, used for the manufacture of experimental electrodes. The purpose of this review is a presentation of the progress to date for the use of new materials and approaches for supercapacitor electrodes, with focus on the energy storage capability for practical applications. A lot of results from published work (research and review papers, patents and reports) are available at this time. As a consequence, many efforts have been made in the last years to increase the storage energy more » density of electrochemical capacitors. Nevertheless, supercapacitors also known as ultracapacitors or electrochemical capacitors have other advantages in comparison with batteries. For lithium ion batteries a value higher than 100 Wh/kg is easily available. The energy density of commercial supercapacitor cells is limited to 10 Wh/kg whereas that of common lead acid batteries reaches 35-40 Wh/kg. As it is known, performance comparison of commercial available batteries and supercapacitors reveals significantly lower energy storage capability for supercapacitor devices. The electrode material is a key component for supercapacitor cell performance. A Additional Journal Information: Journal Volume: 5 Journal Issue: 44 Journal ID: ISSN 2050-7488 Publisher: Royal Society of Chemistry Country of Publication: United States Language: English Subject: 36 MATERIALS = with a nearly 100% coulombic efficiency at room temperature. (BNL), Upton, NY (United States) Sponsoring Org.: USDOE National Science Foundation (NSF) OSTI Identifier: 1425088 Report Number(s): BNL-203294-2018-JAAM Journal ID: ISSN 2050-7488 TRN: US1802040 Grant/Contract Number: SC0012704 CBET-0931587 CMMI-1661699 Resource Type: Journal Article: Accepted Manuscript Journal Name: Journal of Materials Chemistry. Publication Date: Research Org.: Michigan Technological Univ., Houghton, MI (United States) Brookhaven National Lab. School of Environmental Science and Engineering of Materials Science and Engineering Shanghai Jiao Tong Univ.