An asymmetric nanocomposite supercapacitor and a method of making the asymmetric nanocomposite supercapacitor. The asymmetric nanocomposite supercapacitor includes a negative electrode with monoclinic tungsten oxide (m-WO3) nanoplates, and a binding compound coated on one face of a substrate, and a positive electrode with a carbonaceous material and a binding compound coated on one face of a substrate. Where the face of the positive electrode and the face of the negative electrode coated with the carbonaceous material and m-WO3 nanoplates, respectively, are separated by and in direct contact with a porous separator.