1. An electrochromic device comprising: a first electrode; a second electrode opposing the first electrode; a first electrochromic layer and a second electrochromic layer positioned between the first electrode and the second electrode, wherein the first electrochromic layer and the second electrochromic layer include different electrochromic materials, and the different electrochromic materials are either simultaneously n-type or simultaneously p-type; and an electrolyte disposed between the first electrochromic layer and the second electrochromic layer.