Electrochromic multi-layer devices with spatially coordinated switching
View Patent ↗A multi-layer device comprising a first substrate and a first electrically conductive layer on a surface thereof, the first electrically conductive layer having a sheet resistance to the flow of electrical current through the first electrically conductive layer that varies as a function of position.
1. A method of forming an electrochromic multilayer device, comprising:
providing a first substrate comprising a first transparent electrically conductive layer and a second substrate comprising a second transparent electrically conductive layer;
scribing the first conductive layer with a laser to form a first patterned transparent electrically conductive layer having a first simulated sheet resistance to the flow of electrical current that varies as a function of position in the first patterned electrically conductive layer;
scribing the second conductive layer with a laser to form a second patterned transparent electrically conductive layer to have a second simulated sheet resistance to the flow of electrical current that varies as a function of position in the second patterned electrically conductive layer;
forming a first electrode layer comprising an electrochromic material over the patterned first transparent electrically conductive layer;
forming a second electrode layer comprising an electrochromic material over the patterned second transparent electrically conductive layer; and
providing an ion conductor material between the first electrode layer and the second electrode layer to form the electrochromic multilayer device.
2. The method of claim 1 , wherein scribing the first or second transparent electrically conductive layer comprises laser patterning a series of laser scribes.
3. The method of claim 1 , wherein scribing the first conductive layer comprises patterning the first patterned conductive layer to have the first simulated sheet resistance to the flow of electrical current that varies as an increasing function of position in the first patterned electrically conductive layer and wherein scribing the second conductive layer comprises patterning the second patterned conductive layer to have the second simulated sheet resistance to the flow of electrical current that varies as a decreasing function of position in the second patterned electrically conductive layer.
4. The method of claim 1 , wherein scribing the first conductive layer comprises patterning the first patterned conductive layer to have the first simulated sheet resistance to the flow of electrical current that varies as a decreasing function of position in the first patterned electrically conductive layer and wherein scribing the second conductive layer comprises patterning the second patterned conductive layer to have the second simulated sheet resistance to the flow of electrical current that varies as an increasing function of position in the second patterned electrically conductive layer.
5. An electrochromic device, comprising; a first substrate and a second substrate;
a first patterned electrically conductive layer and a second patterned electrically conductive layer, wherein each of the patterned electrically conductive layers has a laser scribe pattern that creates a simulated sheet resistance to the flow of electrical current that varies as a function of position in the first and second patterned electrically conductive layers;
a first electrochromic electrode layer and a second electrochromic electrode layer; and
an ion conducting layer, the first electrochromic electrode layer being between the ion conducting layer and the first electrically conductive layer.
6. The electrochromic device of claim 5 , wherein the simulated sheet resistance of each of the first and second patterned electrically conductive layers has a ratio of the value of maximum simulated sheet resistance, Rmax, to the value of minimum simulated sheet resistance is at least 10.
7. The electrochromic device of claim 5 , wherein the laser scribe pattern is a series of scribes.
8. The electrochromic device of claim 5 , wherein the first and second patterned electrically conductive layers have a uniform thickness in the areas that are not laser scribed.
9. The electrochromic device of claim 5 , wherein the first patterned electrically conductive layer has a first simulated sheet resistance to the flow of electrical current that varies as an increasing function of position in the first patterned electrically conductive layer and wherein the second patterned electrically conductive layer has a second simulated sheet resistance to the flow of electrical current that varies as a decreasing function of position in the second patterned electrically conductive layer.
10. The electrochromic device of claim 5 , wherein the first patterned electrically conductive layer has a first simulated sheet resistance to the flow of electrical current that varies as a decreasing function of position in the first patterned electrically conductive layer and wherein the second patterned electrically conductive layer has a second simulated sheet resistance to the flow of electrical current that varies as an increasing function of position in the second patterned electrically conductive layer.
11. The electrochromic device of claim 5 , wherein the first and second substrates are rectangular and the first and the second simulated sheet resistances have a first and a second gradient, wherein the first and second gradients are non-zero and are of opposite sign.
12. The electrochromic device of claim 5 , wherein (i) the first electrically conductive layer has a spatially varying simulated sheet resistance, R s , that varies as a function of position in the first electrically conductive layer, (ii) a contour map of the simulated sheet resistance, R s , as a function of position within the first electrically conductive layer contains a set of isoresistance lines and a set of resistance gradient lines normal to the isoresistance lines, and (iii) a projection of a line segment having a length of at least 1 cm of one of the gradient lines onto the second electrically conductive layer defines a complementary line segment in the second electrically conductive layer wherein (a) the average value of the slope of the simulated sheet resistance of the first electrically conductive layer over the gradient line segment, S 1 avg , is a positive or negative value, and (b) the average value of the slope of the simulated sheet resistance of the second electrically conductive layer over the complementary line segment, S 2 avg, is zero or is opposite in sign to S 1 avg .
13. The electrochromic device of claim 5 , wherein an Iris Value (delta T) of the electrochromic device having first and second patterned electrically transparent layers is at least 50% less than a comparable device having no patterned electrically transparent layers.
14. The electrochromic device of claim 5 , wherein a switching time between a beached state to a colored state of the electrochromic device having first and second patterned electrically transparent layers is at least twice as fast as a comparable device having no patterned electrically transparent layers.