Electrochromic device and method for making electrochromic device

Abstract

A method for lithiating an electrochromic device comprise forming a first transparent conductive layer on a substrate, forming an electrochromic structure on the first transparent conductive layer, forming a second transparent conductive layer on the electrochromic structure, and lithiating the electrochromic structure through the second transparent conductive layer. In one exemplary embodiment lithiating the electrochromic structure comprises lithiating the electrochromic structure at a temperature range of between about room temperature and about 500 C for the duration of the lithiation process. In another exemplary embodiment, lithiating the electrochromic structure further comprises lithiating the electrochromic structure by using at least one of sputtering, evaporation, laser ablation and exposure to a lithium salt. The electrochromic device can be configured in either a “forward” or a “reverse” stack configuration.

We claim: 
     
         1 . A method of fabricating an electrochromic device, the method comprising:
 a. depositing on a transparent substrate a stack comprising an electrochromic layer, an ion conductor layer and a counter electrode layer; where the ion conductor layer is between the counter electrode layer and the electrochromic layer, and a first transparent conductive oxide layer is adjacent to either the electrochromic layer or the counter electrode layer;   b. depositing a first sublayer of a second transparent conductive oxide layer on either the electrochromic layer or the counter electrode layer, where the first sublayer is between about 10 nm and about 500 nm thick;   c. lithiating the first sublayer; and   d. depositing a second sublayer of the second transparent conductive oxide layer.   
     
     
         2 . The method of  claim 1 , wherein the first sublayer is about 20 nm thick. 
     
     
         3 . The method of  claim 1 , wherein c. is performed at a temperature of between about room temperature and about 500° C. 
     
     
         4 . The method of  claim 1 , wherein the second sublayer is between about 10 nm and about 500 nm thick. 
     
     
         5 . The method of  claim 1 , wherein c. is performed by at least one of sputtering, evaporation, laser ablation and exposure to a lithium salt. 
     
     
         6 . The method of  claim 1 , wherein c. is performed by sputtering. 
     
     
         7 . The method of  claim 1 , wherein the electrochromic layer comprises tungsten oxide, vanadium oxide, niobium oxide or iridium oxide. 
     
     
         8 . The method of  claim 1 , wherein the electrochromic layer comprises tungsten oxide. 
     
     
         9 . The method of  claim 1 , wherein the counter electrode layer comprises nickel oxide, tungsten-doped nickel oxide or iridium oxide. 
     
     
         10 . The method of  claim 1 , wherein the counter electrode layer comprises tungsten-doped nickel oxide. 
     
     
         11 . The method of  claim 1 , wherein the ion conductor layer comprises SiO 2 , TiO 2 , Al 2 O 3  or Ta 2 O 5 . 
     
     
         12 . The method of  claim 1 , wherein the second transparent conductor layer comprises indium tin oxide, fluorine-doped tin oxide, antimony-doped tin oxide or fluorine-doped aluminum oxide. 
     
     
         13 . The method of  claim 1 , wherein the first and second transparent conductor layers have conductivities of less than 20 Ohms per square. 
     
     
         14 . The method of  claim 1 , wherein depositing on a transparent substrate a stack comprises: depositing the electrochromic layer or the counter electrode layer on the first transparent conductive oxide layer. 
     
     
         15 . An electrochromic device comprising:
 a. a transparent substrate;   b. a first transparent conductive oxide layer adjacent to the transparent substrate;   c. an electrochromic layer, an ion conductor layer and a counter electrode layer; wherein the ion conductor layer is between the counter electrode layer and the electrochromic layer, and the first transparent conductive oxide layer is adjacent to either the electrochromic layer or the counter electrode layer;   d. a first sublayer of a second transparent conductive oxide layer on either the electrochromic layer or the counter electrode layer, where the first sublayer is between about 10 nm and about 500 nm thick, wherein the first sublayer is lithiated; and   e. a second sublayer of the second transparent conductive oxide layer disposed on the first sublayer of the second transparent conductive oxide layer.   
     
     
         16 . The electrochromic device of  claim 15 , wherein the first sublayer is about 20 nm thick. 
     
     
         17 . The electrochromic device of  claim 15 , wherein the second sublayer is between about 10 nm and about 500 nm thick. 
     
     
         18 . The electrochromic device of  claim 15 , wherein the electrochromic layer comprises tungsten oxide, vanadium oxide, niobium oxide or iridium oxide. 
     
     
         19 . The electrochromic device of  claim 15 , wherein the electrochromic layer comprises tungsten oxide. 
     
     
         20 . The electrochromic device of  claim 15 , wherein the counter electrode layer comprises nickel oxide, tungsten-doped nickel oxide or iridium oxide. 
     
     
         21 . The electrochromic device of  claim 15 , wherein the counter electrode layer comprises tungsten-doped nickel oxide. 
     
     
         22 . The electrochromic device of  claim 15 , wherein the ion conductor layer comprises SiO 2 , TiO 2 , Al 2 O 3  or Ta 2 O 5 . 
     
     
         23 . The electrochromic device of  claim 15 , wherein the second transparent conductor layer comprises indium tin oxide, fluorine-doped tin oxide, antimony-doped tin oxide, or fluorine-doped aluminum oxide. 
     
     
         24 . The electrochromic device of  claim 15 , wherein the first and second transparent conductor layers have conductivities of less than 20 Ohms per square. 
     
     
         25 . The electrochromic device of  claim 15 , wherein the second sublayer is not lithiated. 
     
     
         26 . An electrochromic device comprising:
 a. a transparent substrate;   b. a first transparent conductive oxide layer adjacent to the transparent substrate;   c. an electrochromic layer, an ion conductor layer and a counter electrode layer; wherein the ion conductor layer is between the counter electrode layer and the electrochromic layer, and the first transparent conductive oxide layer is adjacent to either the electrochromic layer or the counter electrode layer; and   d. a second transparent conductive oxide layer on either the electrochromic layer or the counter electrode layer, wherein the second transparent conductive oxide layer is lithiated.