▎ 摘　　要

NOVELTY - Electrochromic device comprise negative electrode, positive electrode and electrolyte solution, where electrolyte solution is filled between negative electrode and positive electrode, negative electrode is metal nickel electrode, positive electrode is a transparent electrode with an electrochromic layer attached to the surface, and electrolyte solution contains nickel ions. USE - Electrochromic device used in field of display, intelligent window. ADVANTAGE - The electrochromic device is assembled by adopting metal nickel as a cathode, a solution containing nickel ions as an electrolyte solution and an electrochromic material which is colored in an oxidation process and faded in a reduction process as an anode. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for preparation method of electrochromic device,involves(1)preparing an electro-deposition electrochromic layer on the surface of a transparent electrode to obtain a positive electrode;(2)preparing an electrolyte solution; and (3)encapsulating the electrolyte solution between the anode and the metal nickel electrode, and assembling the obtained electrochromic device.