Electrochemical devices and methods for manufacturing them

Description

TECHNICAL FILED

[0001] The present disclosure is related to electrochemical devices and method of forming the same.BACKGROUND ART

[0002] An electrochemical device can include an electrochromic stack where transparent conductive layers are used to provide electrical connections for the operation of the stack. Electrochromic (EC) devices employ materials capable of reversibly altering their optical properties following electrochemical oxidation and reduction in response to an applied potential. The optical modulation is the result of the simultaneous insertion and extraction of electrons and charge compensating ions in the electrochemical material lattice.

[0003] EC devices have a composite structure through which the transmittance of light can be modulated. FIG. 1 illustrates a typical layer solid-state electrochromic device in cross-section having the following superimposed layers: a first transparent conductive layer ("TCL") 11 which serves to apply an electrical potential to the electrochromic device, an electrochromic electrode layer ("EC") 14 which produces a change in absorption or reflection upon oxidation or reduction, an ion conductor layer ("IC") 13 which functionally replaces an electrolyte, allowing the passage of ions while blocking electronic current; a counter electrode layer ("CE") 12 which serves as a storage layer for ions when the device is in the bleached or clear state; and a second transparent conductive layers 15. Each of the aforementioned layers is typically applied sequentially on a substrate 16.

[0004] However, further improvements are sought in the context of electrochromic devices.

[0005] US2016 / 0011480A1 discloses an electrochromic device comprising a stack comprising one or more cathodically tinting electrochromic layers comprising an electrochromic material and one or more anodically tinting counter electrode layers comprising a counter electrode material.SUMMARY

[0006] Subject matter of the present invention is an electrochemical device as defined in claim 1. The dependent claims relate to particular embodiments thereof.

[0007] The electrochemical device comprises a first transparent conductive layer, a cathodic electrochemical layer overlying the first transparent conductive layer, an anodic electrochemical layer overlying the cathodic electrochemical layer, and a second transparent conductive layer. According to the present invention, the electrochemical device further comprises a metallic oxide film between the cathodic electrochemical layer and the anodic electrochemical layer, and a MOxNy layer between the cathodic electrochemical layer and the anodic electrochemical layer, wherein M is a metal, x is between 0.1-6, and y is between 0.1-6.BRIEF DESCRIPTION OF THE DRAWINGS

[0008] FIG. 1 is a schematic cross-section of a typical electrochromic device. FIG. 2 is a schematic cross-section of an electrochromic device with an improved film structure in accordance with an example of the present disclosure. FIG. 3 is a schematic cross-section of an electrochemical device with an improved film structure in accordance with another example of the present disclosure. FIGS. 4A-4E are schematic cross-sections of an electrochemical device at various stages of manufacturing in accordance with an example of the present disclosure. FIG. 5 is a flow chart depicting a process for forming an electrochemical device in accordance with an example of the current disclosure. FIG. 6 is a schematic graph of the impedance of various electrochemical devices. FIG. 7 is a schematic graph of the tinting states of various electrochemical devices. FIG. 8 is a schematic graph of the switching speeds of various electrochemical devices. FIG. 9 is a schematic illustration of an insulated glazing unit according to an example of the current disclosure. FIG. 10 is a schematic graph of the shadowing effects of various electrochemical devices. FIG. 11 is a schematic graph of the apparatus used for FIG. 10. FIG. 12 is a schematic graph of the switching speeds of various electrochemical devices.

[0009] Skilled artisans appreciate that elements in the figures are illustrated for simplicity and clarity and have not necessarily been drawn to scale. For example, the dimensions of some of the elements in the figures may be exaggerated relative to other elements to help to improve understanding of examples of the invention.DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] The following description in combination with the figures is provided to assist in understanding the teachings disclosed herein. The following discussion is provided to assist in describing the teachings and should not be interpreted as a limitation on the scope or applicability of the teachings.

[0011] As used herein, the terms "comprises," "comprising," "includes," "including," "has," "having," or any other variation thereof, are intended to cover a non-exclusive inclusion. For example, a process, method, article, or apparatus that comprises a list of features is not necessarily limited only to those features but may include other features not expressly listed or inherent to such process, method, article, or apparatus. Further, unless expressly stated to the contrary, "or" refers to an inclusive-or and not to an exclusive-or. For example, a condition A or B is satisfied by any one of the following: A is true (or present) and B is false (or not present), A is false (or not present) and B is true (or present), and both A and B are true (or present).

[0012] Patterned features, which include bus bars, holes, holes, etc., can have a width, a depth or a thickness, and a length, wherein the length is greater than the width and the depth or thickness. As used in this specification, a diameter is a width for a circle, and a minor axis is a width for an ellipse.

[0013] The use of "a" or "an" is employed to describe elements and components described herein. This is done merely for convenience and to give a general sense of the scope of the invention. This description should be read to include one or at least one and the singular also includes the plural, or vice versa, unless it is clear that it is meant otherwise.

[0014] The use of the word "about," "approximately," or "substantially" is intended to mean that a value of a parameter is close to a stated value or position. However, minor differences may prevent the values or positions from being exactly as stated.

[0015] "Tinted transmission parameter" is a measurement the percentage of variable light transmission device through an insulated glass unit stabilized at a tinted state measured by a camera / backlight apparatus. The camera and backlight are set up in the following steps. The camera gain and exposure are adjusted such a plain backlight has the brightest pixels with 22% of full scale. The camera is set with no corrections of any kind. The camera is focused on the backlight. White balance numbers from the camera drivers are recorded. The camera records an image with the backlight off as the "dark reference." The dark reference defines 0%T for each pixel. The camera records an image with the backlight on, exposed, and stable as the "bright reference." The bright reference defines 100%T for each pixel. The camera is color calibrated in the following steps. 1. Perform dark and bright reference as given above. 2. Use 12 different color standards to calibrate each tester. Each color standard consists of two 20"x20" colored films purchased from Gam Products, Inc. The chart below gives the specific color and product number for the colored sheets. The two films are placed in a metal frame. Each of the 12 standards are first measured in the equipment HunterLab Colorquest XE, calibrated according to the manufacturer's standards, and recording data using the Universal software - obtaining the values L*,a*,b*. The 12 color standard films are then placed on the (exposed, stable) backlight in the orientation noted in the chart. All other light is blacked out. The area of the image with the color standard is selected in the software and the RGB colors recorded by the camera are noted as in the example below.Standards

[0016] ←Toward Back LightRGBWeightTan (435)Clear0.910.8260.7131Tan (435)Tan (435)0.8920.7430.57490.15 NDNew Green (520)0.5590.5770.4190.3 NDBlue (785)0.2220.3570.48611.2 NDClear0.070.0580.08611.2 NDBlue (785)0.0310.0470.08351.2 ND0.3 ND0.410.0340.0531New Green (520)Yellow (440)0.8180.8420.4231Old Green (540)Clear0.890.9110.7881Yellow (440)Clear0.9120.8780.6633Yellow (440)Old Green (540)0.870.8490.5751Yellow (440)Yellow (440)0.8940.8350.485

[0017] Using L*a*b* color coordinates of standards, find optimum 3x3 matrix to multiply by the camera's measured [R G B] vector to convert it to an accurate [L* a* b*] vector. Start with a 3x3 matrix, [(0.3, 0.3, 0.3) (0.3, 0.3, 0.3) (0.3, 0.3, 0.3)] and multiply this by the measured [ R G B ] vector measured for each standard. This gives an initial calculated XYZ vector. Convert XYZ to Calculated L*a*b* by using the formulas: L * = 116 f Y Y n − 16 a * = 500 f X X n − f Y Y n b * = 200 f Y Y n − f Z Z n Where f(t)=t^(1 / 3) Where Xn=94.8110, Yn=100, Zn=107.304 for the selected illuminant D65 CIE 1964 (10deg)

[0018] Subtract the calculated L*a*b* values from the measured L*a*b* values from Hunterlab to get the delta, then square the delta to get the error in camera measurement for each calculated value L*a*b* for each standard. For each standard: Sum the squared deltas, and multiply them by the weighting value and name them E1, E2,...E12. Take the square root of the sum of E1, E2,... E12 to calculate Overall Error. Use the Solver function in Excel to solve the matrix such that the Overall Error is minimized. Multiplying measured R G B values for each standard will give you the most accurate calculated L*a*b* values. Enter the matrix into the software so that the matrix multiplies the measured RGB values. The software will then use this matrix for all future measurements to convert RGB to XYZ, and then to L*a* b* values. After doing this color calibration, to convert L* to %T: Take three neutral density (ND) filter calibration standards on glass, (2.2mm thick glass, 225x662mm rectangular area covered with neutral density filter with the following %T: 67%T, 45%T, 10%T) and measure HunterLab %T values. Put them on the backlight and cover up all other light. Take an image of the neutral density filters using the camera and record the L*a*b* values measured by the camera (corrected by the matrix as above). The software will compute %T from the equation: %T / 100 = [(L*-16) / 116]^3. To match the measured camera %T measurement with the actual Hunterlab %T measurement for the 3 ND filters: Start with 1:1 Hunterlab%T / camera%T ratio, and adjust the multiplier to 1:1.01, 1:1.02, etc. until the difference between each calculated %T value for the ND filters from the camera is within 0.5 percentage points of the ND filter calibration standards' %T Hunterlab measurement. Enter the multiplier into the software. From this point on, the software will adjust the measured RGB to an accurate L*a*b* and %T measurement for EACH pixel in the image. Each pixel will be assigned a0%-100% %T value by calculating (on a pixel-by-pixel basis) the following: [current reading - dark reference] / [bright reference - dark reference].

[0019] "Switching speed parameter" is a measurement of time in seconds / mm from the time 3V is applied to an electrochemical device to reach the calculated average of UT%T = 5% visible light transmission from a bleached state (-2V) in a dark room with a backlight measured by an RGB camera. The camera and backlight are set up according the procedure described above with respect to the tinted transmission parameter. After the color calibration is completed, the average UT%T is calculated by first calculating the %T for each pixel of the electrochemical device and then calculating the average %T of all the pixels in the electrochemical device collectively.

[0020] "Impedance parameter" is a measurement the effective resistance-a combined effect of ohmic resistance and electrochemical reactance-of an electrochemical device measured at 2 log (freq / Hz) on a 5x5cm device with DC bias at -20°C as 5mV to 50mV is applied to the device. The resultant current is measured and impedance and phase angle are computed at each frequency in the range of 100MHz to 6MHz.

[0021] "Shadowing parameter" is a measurement of the difference in brightness at a time of 8 minutes between an area of a device exposed to the sun and an area of the device within a shadow as -2V is applied to the device. 3V is applied to all three devices at time zero minutes. The devices, S1 and S2, are 40mm x 60mm devices. The device, S3 is a 22.5 inch x 59.5 inch device. The measurement was taken using a camera calibrated as described above. The camera is set such that there is no modulation of the image (no auto-focus, no auto-brightness / contrast), and a pixel brightness of 75% of saturation. The camera is fixed in place 200cm from the back of the devices, 100cm height from the ground, set such that the image captured through the devices contains the white background only and focused on the plane of the device. The measurements were taken at an ambient temperature of 80F, 93,000 lux measured at face of devices. The device faced 267.5 degrees clockwise from the north and 29.94 degrees up from horizon. Tested devices are angled 7 degrees from normal (See curve in FIG. 11). The devices are oriented so that their face is perpendicular to path of sun measured horizontally. Distance from Black Background to Tested Devices is 240cm. Distance from White Background to Tested Devices is 220cm. Black and White backgrounds are normal to horizontal. Area of black and White backgrounds are Equal or larger than the area of the devices. Shadow caster is matte black and 44cm long (in the direction perpendicular to the devices). It is oriented normal to the face of the devices (normal to the 7 degree tilt). Bottom of shadow caster is positioned flush with the top of the devices being tested. Shadow caster is 10% longer on each side of the devices being tested to ensure that there are no unshadowed areas on the face of the device, here it was 300cm long. Devices are tinted and exposed to the sun for 1 hour. The camera took a picture each 4 seconds for 30 minutes. Image data processing: for each frame (a) Select the region of interest (ROI) (shadow and sun part) - these regions are a box 10x10 pixels- Pixels chosen in an area of each device that shows the white background, (b) Convert RGB to LAB as described above (c) Calculate L* mean for each ROI as described above (d) Average the L* for the 10x10 pixel box and (e) Take the difference vs. time between L* sun and L* shadow.

[0022] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The materials, methods, and examples are illustrative only and not intended to be limiting. To the extent not described herein, many details regarding specific materials and processing acts are conventional and may be found in textbooks and other sources within the glass, vapor deposition, and electrochromic arts.

[0023] In accordance with the present disclosure, FIG. 2 illustrates a cross-section view of a partially fabricated electrochemical device 200 having an improved film structure. For purposes of illustrative clarity, the electrochemical device 200 is a variable transmission device. According to the invention, the electrochemical device 200 is an electrochromic device. As further disclosed herein, the electrochemical device 200 can be a thin-film battery. It will be recognized that the present disclosure is similarly applicable to other types of scribed electroactive devices, electrochemical devices, as well as other electrochromic devices with different stacks or film structures (e.g., additional layers). With regard to the electrochemical device 200 of FIG. 2, the device 200 may include a substrate 210, and includes a first transparent conductor layer 220, a cathodic electrochemical layer 230, an anodic electrochemical layer 240, and a second transparent conductor layer 250.

[0024] In an example, the substrate 210 can include a glass substrate, a sapphire substrate, an aluminum oxynitride substrate, or a spinel substrate. In another example, the substrate 210 can include a transparent polymer, such as a polyacrylic compound, a polyalkene, a polycarbonate, a polyester, a polyether, a polyethylene, a polyimide, a polysulfone, a polysulfide, a polyurethane, a polyvinyl acetate, another suitable transparent polymer, or a co-polymer of the foregoing. The substrate 210 may or may not be flexible. In a particular example, the substrate 210 can be float glass or a borosilicate glass and have a thickness in a range of 0.5mm to 12mm thick. The substrate 210 may have a thickness no greater than 16mm, such as 12mm, no greater than 10mm, no greater than 8mm, no greater than 6mm, no greater than 5mm, no greater than 3mm, no greater than 2mm, no greater than 1.5mm, no greater than 1mm, or no greater than 0.01mm. In another particular example, the substrate 210 can include ultra-thin glass that is a mineral glass having a thickness in a range of 50 microns to 300 microns. In a particular example, the substrate 210 may be used for many different electrochemical devices being formed and may referred to as a motherboard.

[0025] Transparent conductive layers 220 and 250 can include a conductive metal oxide or a conductive polymer. Examples include a tin oxide or a zinc oxide, either of which can be doped with a trivalent element, such as Al, Ga, In, or the like, a fluorinated tin oxide, or a sulfonated polymer, such as polyaniline, polypyrrole, poly(3,4-ethylenedioxythiophene), or the like. In another example, the transparent conductive layers 220 and 250 can include gold, silver, copper, nickel, aluminum, or any combination thereof. The transparent conductive layers 220 and 250 can include indium oxide, indium tin oxide, doped indium oxide, tin oxide, doped tin oxide, zinc oxide, doped zinc oxide, ruthenium oxide, doped ruthenium oxide and any combination thereof. The transparent conductive layers 220 and 250 can have the same or different compositions. The transparent conductive layers 220 and 250 can have a thickness between 10nm and 600nm. In one example, the transparent conductive layers 220 and 250 can have a thickness between 200nm and 500nm. In one example, the transparent conductive layers 220 and 250 can have a thickness between 320nm and 460nm. In one example, the first transparent conductive layer 220 can have a thickness between 10nm and 600nm. In one example, the second transparent conductive layer 600 can have a thickness between 80nm and 600nm.

[0026] The layers 230 and 240 are electrode layers, wherein one of the layers is a cathodic electrochemical layer, and the other of the layers is an anodic electrochromic layer (also referred to as a counter electrode layer). The cathodic electrochemical layer 230 is an electrochromic layer. The cathodic electrochemical layer 230 can include an inorganic metal oxide material, such as WO3, V2O5, MoO3, Nb2O5, TiO2, CuO, Ni2O3, NiO, Ir2O3, Cr2O3, Co2O3, Mn2O3, mixed oxides (e.g., W-Mo oxide, W-V oxide), or any combination thereof and can have a thickness in a range of 40nm to 600nm. In one example, the cathodic electrochemical layer 230 can have a thickness between 100nm to 400nm. In one example, the cathodic electrochemical layer 230 can have a thickness between 350nm to 390nm. The cathodic electrochemical layer 230 can include lithium, aluminum, zirconium, phosphorus, nitrogen, fluorine, chlorine, bromine, iodine, astatine, boron; a borate with or without lithium; a tantalum oxide with or without lithium; a lanthanide-based material with or without lithium; another lithium-based ceramic material; or any combination thereof.

[0027] The anodic electrochromic layer 240 can include any of the materials listed with respect to the cathodic electrochromic layer 230 or Ta2O5, ZrO2, HfO2, Sb2O3, or any combination thereof, and may further include nickel oxide (NiO, Ni2O3, or combination of the two), and Li, Na, H, or another ion and have a thickness in a range of 40nm to 500nm. In one example, the anodic electrochromic layer 240 can have a thickness between 150nm to 300nm. In one example, the anodic electrochromic layer 240 can have a thickness between 250nm to 290nm. In some examples, lithium may be inserted into at least one of the first electrode 230 or second electrode 240.

[0028] According to the invention, the device 200 includes metallic oxide film 235 between the two electrode layers 230 and 240. The metallic oxide film 235 may have a thickness of no greater than 10nm, such as no greater than 5nm, no greater than 4nm, no greater than 3nm, no greater than 2nm, or no greater than 1nm. In another example, the metallic oxide film 235 may have a thickness greater than 0, such as greater than 0.1nm, greater than 0.2nm, greater than 0.5nm, or greater than 0.8nm. The metallic oxide film 235 may include lithium, sodium, oxidized lithium, Li2WO4, tungsten, nickel, lithium carbonate, lithium hydroxide, lithium peroxide, or combinations thereof. In one example, the metallic oxide film 235 does not include a polymer. In one example, first transparent conductive layer 220 does not include a polymer. In one example, second transparent conductive layer 250 does not include a polymer. In one example, the cathodic electrochemical layer 230 does not include a polymer. In one example, the anodic electrochemical layer 240 does not include a polymer. In another example, none of the first transparent conductive layer 220, the cathodic electrochemical layer 230, the anodic electrochemical layer 240, the second transparent conductive layer 250, and the metallic oxide film comprise a polymer 235. According to the present invention, the metallic oxide film 235 is oxidized.

[0029] In another example, the device 200 may include a plurality of layers between the substrate 210 and the first transparent conductive layer 220. In one example, an antireflection layer is between the substrate 210 and the first transparent conductive layer 220. The antireflection layer can include SiO2, NbO2, and can have a thickness between 20nm to 100nm. The device 200 may include at least two bus bars. In the example of FIG. 2, two bus bars 260, 270 are shown. The bus bar 260 can be electrically connected to the first transparent conductive layer 220 and the bus bar 270 can be electrically connected to the second transparent conductive layer 250.

[0030] FIG. 3 is a schematic cross-section of an electrochemical device 300 with an improved film structure in accordance with another example of the present disclosure. The electrochemical device 300 is an electrochromic device. The electrochemical device 300 is similar to the electrochemical device 200. The electrochemical device 300 can include a substrate 310, and includes a first transparent conductive layer 320, a cathodic electrochemical layer 330, a metallic oxide film 335, a layer 380, an anodic electrochemical layer 340, a second transparent conductive layer 350, a first bus bar 360, and a second bus bar 370. According to the present invention, the layer 380 is a metal oxinitride (MOxNy)-where M is a metal, x is between 0.1-6, and y is between 0.1-6. In an alternative example disclosed herein, the layer 380 can be a SiOx:Al layer.

[0031] The first transparent conductive layer 320 is between the substrate 310 and the cathodic electrochemical layer 330. In one example, the first transparent conductive layer 320 includes a P1 gap to prevent an electrical short of the electrochemical device 300. In one example, the first transparent conductive layer 320 is electrically isolated from the second transparent conductive layer 370 through the P1 gap. In one example, the first transparent conductive layer 320 is electrically connected to the first transparent conductive layer 360. The metallic oxide film 335 is between the cathodic electrochemical layer 330 and the anodic electrochemical layer 340. In one example, the metallic oxide film 335 can be on the cathodic electrochemical layer 330. In one example, the metallic oxide film 335 can be on the layer 380.

[0032] According to the present invention, the layer 380 is between the cathodic electrochemical layer 330 and the anodic electrochemical layer 340. In one example, the layer 380 can be on the cathodic electrochemical layer 330. In one example, the layer 380 can be on the metallic oxide film 335. The layer 380 can include silicates, silicon oxides, tungsten oxides, tantalum oxides, niobium oxides, borates, aluminum oxides, lithium silicate, lithium aluminum silicate, lithium aluminum borate, lithium aluminum fluoride, lithium borate, lithium nitride, lithium zirconium silicate, lithium niobate, lithium borosilicate, lithium phophosilicate, other lithium-based ceramic materials, lithium salts, and dopants including lithium, sodium, hydrogen, deuterium, potassium, calcium, barium, strontium, magnesium, or combinations thereof. In one example, the layer 380 can have a thickness between 0.5nm and 11nm. In one example, the layer 380 can have a thickness no greater than 10nm, such as 5nm, no greater than as 4nm, no greater than 3nm, no greater than 2nm, or no greater than 1nm.

[0033] The anodic electrochemical layer 340 is between the second transparent conductive layer 350 and the cathodic electrochemical layer 330. In one example, the second transparent conductive layer 350 can be on the anodic electrochemical layer 340. In one example, the anodic electrochemical layer 340 can be on the layer 380. In another example, the anodic electrochemical layer 340 can be on the metallic oxide film 335.

[0034] In another example, the electrochemical devices 200 and 300 may include additional layers. In one example, a sealing layer including a silica oxide may be deposited on the anodic electrochemical layer.

[0035] FIG. 5 is a flow chart depicting a process 500 for forming an electrochromic device in accordance with an example of the current disclosure. FIGS. 4A-4E are a schematic cross-section of an electrochromic device 400 at various stages of manufacturing in accordance with an example of the present disclosure. The electrochromic device 400 is the same as the electrochromic devices 200 and 300 described above. The process includes providing a substrate 410. The substrate 410 is similar to the substrate 210, 310 described above. At operation 510, a first transparent conductive layer 420 is deposited on the substrate 410, as seen in FIG. 3A. The first transparent conductive layer 420 is similar to the first transparent conductive layer 220, 320 described above. In one example, the deposition of the first transparent conductive layer 420 can be carried out by sputter deposition at a power of between 5kW and 20kW, at a temperature between 200°C and 400°C, in a sputter gas including oxygen and argon at a rate between 0.1 m / min and 0.5 m / min. In one example, the sputter gas includes between 40% and 80% oxygen and between 20% and 60% argon. In one example, the sputter gas includes 50% oxygen and 50% argon. In one example, the temperature of sputter deposition can be between 250°C and 350°C. In one example, the first transparent conductive layer 420 can be carried out by sputter deposition at a power of between 10kW and 15kW.

[0036] In one example, an intermediate layer can be deposited between the substrate 410 and the second transparent conductive layer 220, 320. In an example, the intermediate layer can include an insulating layer such as an antireflective layer. The antireflective layer can include a silicon oxide, niobium oxide, or any combination thereof. In a particular example, the intermediate layers can be an antireflective layer that can be used to help reduce reflection. The antireflective layer may have an index of refraction between the underlying layers (refractive index of the underlying layers can be approximately 2.0) and clean, dry air or an inert gas, such as Ar or N2 (many gases have refractive indices of approximately 1.0). In an example, the antireflective layer may have a refractive index in a range of 1.4 to 1.6. The antireflective layer can include an insulating material having a suitable refractive index. In a particular example, the antireflective layer may include silica. The thickness of the antireflective layer can be selected to be thin and provide the sufficient antireflective properties. The thickness for the antireflective layer can depend at least in part on the refractive index of the electrochromic layer 430 and counter electrode layer. The thickness of the intermediate layer can be in a range of 20nm to 100nm.

[0037] At operation 520 and as seen in FIG. 4B, an electrochromic layer 430 is deposited on the first transparent conductive layer 420. The electrochromic layer 430 is similar to the electrochromic layer 230, 330 described above. In one example, the deposition of the electrochromic layer 430 may be carried out by sputter deposition of tungsten, at a temperature between 23°C and 400°C, in a sputter gas including oxygen and argon. In one example, the sputter gas includes between 40% and 80% oxygen and between 20% and 60% argon. In one example, the sputter gas includes 50% oxygen and 50% argon. In one example, the temperature of sputter deposition is between 100°C and 350°C. In one example, the temperature of sputter deposition is between 200°C and 300°C. An additionally deposition of tungsten may be sputter deposited in a sputter gas that includes 100% oxygen.

[0038] At operation 530 and as seen in FIG. 4C, a metal layer 435 is deposited on the electrochromic layer 430. The metal layer 435 can be similar to the metal layer 235, 335 described above. The metal layer 435 may include lithium, sodium, oxidized lithium, Li2WO4, tungsten, nickel, lithium carbonate, lithium hydroxide, lithium peroxide, or combinations thereof. In one example, the deposition of the metal layer 435 may be carried out by sputter deposition at a power of between 5kW and 12kW. In one example, the power is pulsed. In another example, the sputter target can be rotated to point away from the substrate. The deposition of the metal may be at a temperature between 23°C and 500°C in a sputter gas including oxygen and argon. In one example, the temperature of sputter deposition is between 150°C and 450°C. In another example, the deposition of the metal layer 435 may be carried out in a sputter gas including between 0% and 5% oxygen and between 100% to 95% argon. In one example, the metal layer 435 may be deposited to form a layer with a thickness between 1nm and 5nm. In one example, the metal layer may have a thickness of no greater than 5nm, such as no greater than 4nm, no greater than 3nm, no greater than 2nm, or no greater than 1nm.

[0039] According to one embodiment of the present invention, a MOxNy layer is deposited on the metal layer 435. According to another embodiment of the present invention, the MOxNy layer is deposited on the cathodic electrochromic layer 330. The MOxNy layer is similar to the MOxNy layer 380. In one example, the deposition of the MOxNy layer may be carried out by sputter deposition of silica, lithium, at a temperature between 150°C and 450°C, in a sputter gas including oxygen and argon. In one example, the sputter gas includes between 40% and 80% oxygen and between 20% and 60% argon. In one example, the MOxNy layer may be deposited to form a layer with a thickness between 1nm and 12nm. In one example, the MOxNy layer may be deposited to form a layer with a thickness between 2nm and 8nm. In one example, the metal layer may have a thickness of no greater than 12nm, such as 10nm, no greater than 5nm, no greater than as 4nm, no greater than 3nm, no greater than 2nm, or no greater than 1nm.

[0040] At operation 540, the metal layer 435 is oxidized to form a metallic oxide film 436. The oxidation of the metal layer 435 may be completed before the deposition of any subsequent layers, such as the anodic electrochemical layer 440. According to one embodiment of the present invention, the metallic oxide film 436 is on the cathodic electrochemical layer 430. According to another embodiment of the present invention, the metallic oxide film 436 is on the MOxNy layer. In one example, oxidizing the metal layer to form the metallic oxide film 436 can be carried out after breaking vacuum but before depositing any subsequent layers. In another example, oxidizing the metal layer 435 to form the metallic oxide film 436 can be carried out in an environment including ionized gas. In yet another example, oxidizing the metal layer 435 to form the metallic oxide film 436 can occur in a controlled environment, without vacuum break, but instead by introducing an oxidizing agent into the controlled environment. The ionized agent can include argon, oxygen, nitrogen, oxygen ions, and nitrogen ions, or any combination thereof. Without wishing to be tied to any particular theory, it is believed that prior to formation of overlying layers, the deposited metal layer 435 is oxidized to form various compounds at and along the cathodic electroactive interface. The treatment is understood to modify the metallic rich region in a manner that various performance advantages can be seen, such as a faster switching speed and a richer tinting color as seen below.

[0041] In one example, the oxidation of the metal layer 435 to form the metallic oxide film 436 may be in conjunction with heating the deposited layers. In one example the substrate 410, the first transparent conductive layer 420, the metal layer 435, and the electrochromic layer 430 may be heated at a temperature between 23°C and 500°C in atmospheric air for between 1 min. and 30 min. In other words, the substrate and subsequent deposited layers may break vacuum before being heated. In one example, the substrate and subsequent layers may be heated in atmospheric air for between 1 min. and 5min. In one example, the metal layer 435 may be oxidized in situ in an oxygen environment using a plasma source. As such, the substrate 410, the first transparent conductive layer 420, the metal layer 435, and the cathodic electrochemical layer 430 may be heated by the plasma source and the metal layer 435 oxidized before subsequent deposition of layers. In one example, the substrate 410, the first transparent conductive layer 420, the metal layer 435, and the electrochromic layer 430 may be heated at a temperature between 200°C and 400°C. In one example, the substrate 410, the first transparent conductive layer 420, the metal layer 435, and the electrochromic layer 430 may be heated at a temperature between 300°C and 380°C.

[0042] In yet another example, the metal layer 435 may be oxidized to form the metallic film 436 in a low temperature oxidation process. In one example, the temperature may be between 23°C and 100°C. In one example, the substrate and subsequent layers can be oxidized in a halogen rich environment. The halogen rich environment can include between 20% and 100% oxygen and 0% to 80% nitrogen. In one example, the halogen rich environment can include 100% oxygen. In one example, the halogen rich environment can include carbon dioxide.

[0043] At operation 550, after oxidization of the metallic film 436, a counter electrode layer 440 is deposited on the metallic oxide film 436. In one example, the counter electrode 440 is deposited on the MOxNy layer. The counter electrode layer 440 is similar to the counter electrode layer 240, 340 described above. In one example, the deposition of the counter electrode layer 440 may be carried out by sputter deposition of tungsten, nickel, and lithium, at a temperature between 20°C and 50°C, in a sputter gas including oxygen and argon. In one example, the sputter gas includes between 60% and 80% oxygen and between 20% and 40% argon. In one example, the temperature of sputter deposition is between 22°C and 32°C.

[0044] At operation 560 and as seen in FIG. 4E, a second transparent conductive layer 450 is deposited on the counter electrode layer 440. The second transparent conductive layer 450 is similar to the second transparent conductive layer 450 described above. In one example, the deposition of the second transparent conductive layer 450 may be carried out by sputter deposition at a power of between 5kW and 20kW, at a temperature between 20°C and 50°C, in a sputter gas including oxygen and argon. In one example, the sputter gas includes between 1% and 10% oxygen and between 90% and 99% argon. In one example, the sputter gas includes 8% oxygen and 92% argon. In one example, the temperature of sputter deposition is between 22°C and 32°C. In one example, the substrate 410, first transparent conductive layer 420, the electrochromic layer 430, the counter electrode layer 440, and the second transparent conductive layer 450 may be heated a at a temperature between 300°C and 500°C for between 2 min and 10 min. In one example, additional layers may be deposited on the second transparent conductive layer 450.

[0045] After depositing the second transparent conductive layer 450, the stack including the substrate 410, the first transparent conductive layer 420, the cathodic electrochemical layer 430, the metallic oxide film 436, the anodic electrochemical layer 440, and the second transparent conductive layer 450 can be heated at a temperature between 300°C and 700°C. In one example, the stack is heated at a temperature between 400°C and 450°C. In one example, the substrate 410, the first transparent conductive layer 420, the cathodic electrochemical layer 430, the metallic oxide film 436, the anodic electrochemical layer 440, and the second transparent conductive layer 450 can be heated at a temperature between 400°C and 670°C. In one example, the stack is heated for a period between 1 min. and 30 mins. In one example, the stack is heated for a period between 3 mins. and 5 mins. In one example, the stack is heated by laser anneal. In another example, the stack is heated after breaking vacuum.

[0046] Any of the electrochemical devices can be subsequently processed as a part of an insulated glass unit. The electrochemical devices' performance, once processed, can be assessed using the switching speed parameter. However, there are several factors that contribute to the switching speed parameter and, dependent upon the size of the device, each factor may be the rate-limiting step. The insulated glass unit can be a window between 10"x10" to a 40"x42". In another example, the insulated glass unit can be a window between 10"x10" to a 20"x22". In one example, the insulated glass unit can be a window greater than 10" squared, such as greater than 12" squared, or greater than 15" squared, or greater than 20" squared, or greater than 30" squared, or greater than 35" squared. In another example, the window is rectangular and greater than 10"x12", such as greater than 10"x14", or greater than 12"x14", or greater than 20"x24". The factors that contribute to the switching speed parameter are the through-stack thickness impedance, the transparent conductive oxide layers, and the driving force for lithium ions. In order to further illustrate, a few examples are given below. Each of the factors can be a rate-limiting step dependent upon the size of the electrochemical device. In one example where devices are less than 10"x10", the rate limiting step can be the through-stack thickness impedance. The through-stack thickness impedance limits the speed of the lithium ion movement between the stack layers. However, each layer in the stack behaves differently depending on the thickness of each layer in the final electrochemical device. As such, it becomes difficult to pin-point the exact layer causing the most impedance. The inventors have found that by measuring a variety of sizes of electrochemical devices, measuring a varies of aspect ratios, measuring a variety of layer thicknesses, and correlating the data to a physics based model, the impedance signals can be shown as a function of frequency to each layer of the stack. By determining the frequency to each layer of the stack, it can be determined which layer is causing the most impedance. As such, the amount of deposition time can be adjusted as each layer is deposited during the process described above to increase the switching speed.

[0047] In one example where devices are greater than 10"x10", the rate limiting step can be the transparent conductive oxide (TCO) layers. Each TCO layer can be made of different material which leads to different resistive properties. In, for example, devices where the bus bars are spaced at the edge of the device and the device is greater than 10" wide, the electronic conduction through the transparent conducting oxide layers can be the rate limiting step for the switching speed parameter. Accordingly, the switching speed parameter can be slower in electrochemical devices with larger bus bar spacing, as seen for example in devices greater than 10". In other words, there is an inverse property between the bus bar spacing and the switching speed parameter; as the bus bar spacing increases the switching speed decreases. However, by depositing the TCOs as noted above, the inventors have been able to reduce the resistance in the TCO layers and increase the switching speed parameter.

[0048] Additionally, the applied voltage to the electrochemical device can determine the driving force for lithium ions as they move from one layer to the other. At rest, the lithium ions mostly reside in the counter electrode layer, where the lithium ions have a lower potential energy than when in the electrochemical layer, with an activation barrier impeding them from moving in the electrochromic layer. An applied voltage changes the relative potential energy of the counter electrode layer and the electrochromic layer, and also the activation barrier height, such that the lithium ions move from the counter electrode layer to the electrochemical layer. The higher the voltage, the faster the activation barrier can be overcome and the faster the lithium ions can move to the electrochromic layer thus improving the switching speed parameter of the device. However, if the voltage is too high, the voltage can damage the material in the layers and introduce an electronic leakage current. As such, the driving force or applied voltage has to be adjusted according the thicknesses of each layer. For the devices described herein, a voltage between -5V and +5V can be used.

[0049] FIG. 9 is a schematic illustration of an insulated glazing unit 900 according to the example of the current disclosure. The insulated glass unit 900 includes a first panel 905, an electrochemical device 920 coupled to the first panel, a second panel 910, and a spacer 915 between the first panel 905 and second panel 910. The first panel 905 can be a glass panel, a sapphire panel, an aluminum oxynitride panel, or a spinel panel. In another example, the first panel can include a transparent polymer, such as a polyacrylic compound, a polyalkene, a polycarbonate, a polyester, a polyether, a polyethylene, a polyimide, a polysulfone, a polysulfide, a polyurethane, a polyvinyl acetate, another suitable transparent polymer, or a co-polymer of the foregoing. The first panel 905 may or may not be flexible. In a particular example, the first panel 905 can be float glass or a borosilicate glass and have a thickness in a range of 2mm to 20mm thick. The first panel 905 can be a heat-treated, heat-strengthened, or tempered panel. In one example, the electrochemical device 920 is coupled to first panel 905. In another example, the electrochemical device 920 is on a substrate 925 and the substrate 925 is coupled to the first panel 905. In one example, a lamination interlayer 930 may be disposed between the first panel 905 and the electrochemical device 920. In one example, the lamination interlayer 930 may be disposed between the first panel 905 and the substrate 925 containing the electrochemical device 920. The electrochemical device 920 may be on a first side 921 of the substrate 925 and the lamination interlayer 930 may be coupled to a second side 922 of the substrate. The first side 921 may be parallel to and opposite from the second side 922.

[0050] The second panel 910 can be a glass panel, a sapphire panel, an aluminum oxynitride panel, or a spinel panel. In another example, the second panel can include a transparent polymer, such as a polyacrylic compound, a polyalkene, a polycarbonate, a polyester, a polyether, a polyethylene, a polyimide, a polysulfone, a polysulfide, a polyurethane, a polyvinyl acetate, another suitable transparent polymer, or a co-polymer of the foregoing. The second panel may or may not be flexible. In a particular example, the second panel 910 can be float glass or a borosilicate glass and have a thickness in a range of 5mm to 30mm thick. The second panel 910 can be a heat-treated, heat-strengthened, or tempered panel. In one example, the spacer 915 can be between the first panel 905 and the second panel 910. In another example, the spacer 915 is between the substrate 925 and the second panel 910. In yet another example, the spacer 915 is between the electrochemical device 920 and the second panel 910.

[0051] In another example, the insulated glass unit 900 can further include additional layers. The insulated glass unit 900 can include the first panel, the electrochemical device 920 coupled to the first panel 905, the second panel 910, the spacer 915 between the first panel 905 and second panel 910, a third panel, and a second spacer between the first panel 905 and the second panel 910. In one example, the electrochemical device may be on a substrate. The substrate may be coupled to the first panel using a lamination interlayer. A first spacer may be between the substrate and the third panel. In one example, the substrate is coupled to the first panel on one side and spaced apart from the third panel on the other side. In other words, the first spacer may be between the electrochemical device and the third panel. A second spacer may be between the third panel and the second panel. In such an example, the third panel is between the first spacer and second spacer. In other words, the third panel is coupled to the first spacer on a first side and coupled to the second spacer on a second side opposite the first side.

[0052] The examples described above and illustrated in the figures are not limited to rectangular shaped devices. Rather, the descriptions and figures are meant only to depict cross-sectional views of a device and are not meant to limit the shape of such a device in any manner. For example, the device may be formed in shapes other than rectangles (e.g., triangles, circles, arcuate structures, etc.). For further example, the device may be shaped three-dimensionally (e.g., convex, concave, etc.).EXAMPLES

[0053] An example is provided to demonstrate the performance of an electrochemical device with a metallic oxide film as compared to other electrochemical devices with varying layers. For the various examples below, sample 1 (S1) was formed in accordance to the various examples described above. Comparative sample, Sample 2 (S2) is understood to be an example without an ion-conducting layer, as described in U.S. Patent No. 8,758,575, U.S. Patent No. 8,582,193, and U.S. Patent No. 9,261,751. Comparative sample, Sample 3 (S3) is understood to be an example with an ion-conducting layer, as described in U.S. Patent No. 9,581,875.

[0054] FIG. 6 is a modulus graph of the impedance of various samples S1, S2, and S3. As can be seen in FIG. 6, impedance is the absolute value of Z. The y-axis is however, the phase angle at each frequency in the range of 100MHz to 6MHz. The x-axis is the log of Z in - 20°C in the frequency range of 101-106Hz. At a parameter of 2, S1 has an impedance parameter of log|Z| of less than 1.5 / log (ohm), such as less than 1.2 / log (ohm), or less than 1 / log (ohm). At the parameter of 2, S2 and S3 have an impedance of greater than 1.5 / log (ohm).

[0055] FIG. 7 is a schematic graph of the tinting states of the various samples S1, S2. The y-axis is the tinted percentage and the x-axis is the bleached percentage at -20°C. S1 has a tinted transmission parameter of less than 8%, such as less than 7%, less than 6%, less than 5%, less than 4%, or less then 3%.

[0056] FIG. 8 is a schematic graph of the switching speeds of various samples S1 (a, b, and c), S2, and S3. FIG. 8 shows the 95% confidence interval of switching speed s / mm at 23°C. Below is Table 1 with the data from the graph of FIG. 8. MeanStd DevLowHighSample 1a (S1a)0.610.070.450.73Sample 1b (S1b)0.340.050.280.41Sample 1c (S1c)0.5.15.45.65Sample 2 (S2)0.890.130.761.02Sample 3 (S3)0.730.200.751.28

[0057] S2 has an average switching speed of 0.89 s / mm, with the lowest switching speed of 0.76 s / mm. S1a has an average switching speed of 0.61 s / mm, with the highest switching speed of 0.73 s / mm. S1a can be the same as S1 above. S1b has an average switching speed of 0.34 s / mm, with the lowest switching speed of 0.28 s / mm. S1c has an average switching speed of 0.5 s / mm, with the highest switching speed of 0.65 s / mm. S3 has an average switching speed of 0.73 s / mm, with the lowest switching speed of 0.75 s / mm. Switching speed changes with temperature. Below is Table 2 with data of switching speed s / mm of S1 and S2 at -20°C. MeanLowHighSample 1 (S1)0.720.720.72Sample 2 (S2)1.221.11.38

[0058] S1 can have an average switching speed of 0.72 s / mm. S2 has an average switching speed of 1.22 s / mm, with the lowest switching speed of 1.1 s / mm. S1 can have a switching speed parameter of not greater than 1.0 s / mm, such as 0.9 s / mm, no greater than 0.8 s / mm, or no greater than 0.7 s / mm at -20°C.

[0059] FIG. 10 is a schematic graph of the shadowing effects of various electrochemical devices, S1, S2, and S3 as measured by the change in brightness between an area in the sun and an area in a shadow over a period of ten minutes. Delta L is the difference in brightness between the area in the sun and the area in the shadow. As can be seen, S1 has a delta L of less than 2.5L*, such as 2.4L*, less than 2.3L*, less than 2.2L*, less than 2.1L*, less than 1.9L*, less than 1.8L*, less than 1.7L*, less than 1.6L*, less than 1.5L*, less than 1.4L*, less than 1.3L*, less than 1.2L*, or less than 1.1L*at 8 min. S2 and S3 have a delta L above 3.

[0060] FIG. 12 is a schematic graph of the switching speeds of various samples S1 (a and b), S2, and S3. FIG. 12 shows time in seconds it takes a 5x5cm pixel to go from 50% transmission (T) to 5%T. Each device had electrical contacts applied to the top and bottom ITO with copper tape and ultrasonic solder. A white LED and light detector measured the %TL from a clear state. +2V were applied to the pixel for 10 minutes and the %T measured simultaneously. Below is Table 3 with the data from the graph of FIG. 12. Time (seconds)Sample 1a (S1a)11.9Sample 1b (S1b)10.1Sample 2 (S2)21.6Sample 3 (S3)70.3

[0061] As seem in both Table 3 and FIG. 12, S1 has a faster switching speed than S2 and S3. S1a goes from 50%T to 5%T in 11.9 seconds. S1b goes from 50%T to 5%T in 10.1 seconds. S2 goes from 50%T to 5%T in 21.6 seconds. S3 goes from 50%T to 5%T in 70.3 seconds.

[0062] The specification and illustrations of the examples described herein are intended to provide a general understanding of the present invention. The specification and illustrations are not intended to serve as an exhaustive and comprehensive description of all of the elements and features of apparatus and systems that use the structures or methods described herein.

Claims

1. An electrochemical device (200, 300, 400) comprising: a first transparent conductive layer (11, 220, 320, 420); a cathodic electrochemical layer (14, 230, 330, 430) overlying the first transparent conductive layer (11, 220, 320, 420); an anodic electrochemical layer (12, 240, 340, 440) overlying the cathodic electrochemical layer (14, 230, 330, 430); a second transparent conductive layer (15, 250, 350, 450); characterized in that the electrochemical device (200, 300, 400) further comprises a metallic oxide film (235, 335, 436) between the cathodic electrochemical layer (14, 230, 330, 430) and the anodic electrochemical layer (12, 240, 340, 440), and a MOxNy layer (380) between the cathodic electrochemical layer (14, 230, 330, 430) and the anodic electrochemical layer (12, 240, 340, 440), wherein M is a metal, x is between 0.1-6, and y is between 0.1-6, and wherein either the metallic oxide film (235, 335, 436) is on the cathodic electrochemical layer (14, 230, 330, 430) and the MOxNy layer (380) is on the metallic oxide film (235, 335, 436), or the MOxNy layer (380) is on the cathodic electrochemical layer (14, 230, 330, 430) and the metallic oxide film (235, 335, 436) is on the MOxNy layer (380).

2. The electrochemical device (200, 300, 400) of claim 1, wherein the metallic oxide film (235, 335, 436) comprises lithium, sodium, hydrogen, deuterium, potassium, calcium, barium, strontium, magnesium, oxidized lithium, Li2WO4, tungsten, nickel, lithium carbonate, lithium hydroxide, lithium peroxide, or any combination thereof.

3. The electrochemical device (200, 300, 400) of claim 1, wherein the cathodic electrochemical layer (14, 230, 330, 430) comprises a material selected from the group consisting of WO3, V2O5, MoO3, Nb2O5, TiO2, CuO, Ni2O3, NiO, Ir2O3, Cr2O3, Co2O3, Mn2O3, mixed oxides (e.g., W-Mo oxide, W-V oxide), lithium, aluminum, zirconium, phosphorus, nitrogen, fluorine, chlorine, bromine, iodine, astatine, boron, a borate with or without lithium, a tantalum oxide with or without lithium, a lanthanide-based material with or without lithium, another lithium-based ceramic material, or any combination thereof.

4. The electrochemical device (200, 300, 400) of claim 1, wherein the MOxNy layer (380) comprises an alkaline earth metal, transition metal, Zn, Ga, Ge, Al, Cd, In, Sn, Sb, Pb, Bi, B, Si, P, S, As, Se, Te, silicates, silicon oxides, tungsten oxides, tantalum oxides, niobium oxides, borates, aluminum oxides, lithium silicate, lithium aluminum silicate, lithium aluminum borate, lithium aluminum fluoride, lithium borate, lithium nitride, lithium zirconium silicate, lithium niobate, lithium borosilicate, lithium phophosilicate, other lithium-based ceramic materials, lithium salts, and dopants including lithium, sodium, hydrogen, deuterium, potassium, calcium, barium, strontium, magnesium, or combinations thereof.

5. The electrochemical device (200, 300, 400) of claim 1, wherein the MOxNy layer (380) has a thickness of no greater than 10nm.