J. Electrochem. Sci. Technol., 2019, 10(2), 159-169 - 159 - Preparation of Biomass Based Carbon for Electrochemical Energy Storage Application V.S.Harshini Priyaa, R.Saravanathamizhan*, and N.Balasubramanian Department of Chemical Engineering, A.C.Tech., Anna University, Chennai-600025, India ABSTRACT The activated carbon materials were prepared from waste biomass by ultrasonic assisted chemical activation method (UCA), ultrasonic assisted physical activation method (UPA) and Manganese nitrogen doped carbon (Mn/N-C). The XRD result shows the turbostatic (fully disordered) structure. The cyclic voltammetry test was done at 50 mV/s using 1M sodium sulfate and the values of specific capacitance were found to be 93, 100 and 115 F/g for UCA, UPA and Mn/N-C respec- tively. The power density values for the samples UCA, UPA and Mn/N-C were found to be 46.04, 87.97 and 131.42 W/kg respectively. The electrochemical impedance spectroscopy was done at low frequency between 1 to 10 kHz. The Nyquist plot gives the resistant characteristics of the materials due to diffusional resistance at the electrode–electrolyte interface. The Energy Dispersive X-Ray Spectroscopyanalysis (EDAX) analysis showed that the percentage doping of nitrogen and man- ganese were 3.53 wt% and 9.44 wt% respectively. It is observed from the experiment Mn/N-C doped carbon show good physical and electrochemical properties. Keywords : Activated carbon, Biomass, Electrochemical energy storage, Super capacitor, Ultrasonic assisted Received : 13 June 2018, Accepted : 10 November 2018 1. Introduction Electrochemical energy storage devices were used to store the produced energy and discharge it at the time of use. Electrochemical secondary batteries; fuel cells and supercapacitor are the three main types of electrochemical storage devices each having its own advantages. Supercapacitors also have distinctive advantages such as high-power density, long cycle life, rapid charge and discharge, safe operation and power delivery at extreme climatic conditions [1-3]. The key issues of supercapacitors are their low energy density. Till now commercially available supercapacitors can only provide an energy density of less than 10Wh/kg. Whereas, Lithium ion batteries can provide an energy density of more than 180 W h / kg. Therefore, research works are being carried out to enhance the energy density of supercapacitors by developing new electrode materials, novel electro- lytes with a wide operation voltage window, or an ingenious device design. Several types of superca- pacitors can be distinguished, depending upon the charge storage mechanism as well as the active mate- rial type. Electric double layer capacitors (EDLC) use activated carbon materials as a electrodes and stores the charge electrostatically by reversible adsorption of electrolyte ions onto active materials that are electrochemically stable having large specific surface area, on which the charge is separated on polarization at the electrode–electrolyte interface. Pseudo-capacitors or redox supercapacitors use transition metal oxides as well as electrically con- ducting polymers and electric energy is stored by Faradic redox reactions between the electrolyte ions and the electrode, thus forming capacitance. The electrode materials play a vital role in the electro capacitive mechanism of the supercapacitors. The electrode materials are characterized based on their specific capacitance, the specific surface area, pore size and geometry and electronic and ionic conductiv- ity. Carbon based materials tend to have better cycle stability and rate capability thus the supercapacitors Research Article *E-mail address: thamizhan79@rediffmail.com, rsthamizhan@gmail.com DOI: https://doi.org/10.5229/JECST.2019.10.2.159 This is an open-access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/4.0) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.