Abstract
An asymmetric supercapacitor includes a negative electrode made of a first carbon, a positive electrode made of a pre-treated carbon, a separator and an electrolyte. The separator is disposed in between the negative and positive electrodes. The carbon has an activation threshold (AT) larger than 1400, and the activation threshold (AT) is obtained from the following formula: AT=La*(Aa/Ac). Lais a graphite in-plane relative length of the carbon, Aais an area of a broad peak of the carbon between 22.5 o and 27.5 o analysed by X-ray diffraction in Gaussian distribution graph, and Acis an area of the (002) diffraction peak of the carbon analysed by X-ray diffraction in Gaussian distribution graph.