Electrochromic multi-layer devices with cross-linked ion conducting polymer
Multi-layer electrochromic structures, and processes for assembling such structures, incorporating a cross-linked ion conducting polymer layer that maintains high adhesive and cohesive strength in combination with high ionic conductivity for an extended period of time, the ion conducting polymer layer characterized by electrochemical stability at voltages between about 1.3 V and about 4.4 V relative to lithium, lithium ion conductivity of at least about 10 −5 s/cm, and lap shear strength of at least 100 kPa, as measured at 1.27 mm/min in accordance with ASTM International standard D1002 or D3163.
1. An ion conducting polymer feedstock material comprising:
a cross-linkable ion conducting polymer comprising about 5 wt. % to about 50 wt. % of the feedstock material;
an ionizable charge carrier;
a moisture reduction additive comprising particles having a particle size of less than 350 nm; and
a plasticizer;
wherein, the ion conducting polymer feedstock material has a viscosity of about 20,000 cP to about 50,000 cP.
2. The ion conducting polymer feedstock material of claim 1 , wherein the ion conducting polymer comprises a mixture of monomers and oligomers.
3. The ion conducting polymer feedstock material of claim 2 , wherein the monomers comprise at least one functional group selected from the group of epoxy, hydroxyl, carbonyl, sulfonyl, ethylene, styrene, vinyl, isocyanate, and acrylate.
4. The ion conducting polymer feedstock material of claim 2 , wherein the monomers comprise epoxide monomers wherein the epoxide monomers are selected from the group consisting of: bis[1-ethyl(3-oxetanyl)]methyl ether, bisphenol-A diglycidyl ether, diglycidyl 1,2-cyclohexanedicarboxylate, 1,4-cyclohexanedimethanol diglycidyl ether, pentaerythritol tetraglycidyl ether, trimethylolpropane triglycidylether, and butanediol diglycidyl ether.
5. The ion conducting polymer feedstock material of claim 1 , wherein the plasticizer is selected from the group of sulfolane, 3-methyl sulfolane, propylene carbonate, ethylene carbonate, polyethylene glycol dimethyl ether, and polyethylene glycol methyl ether methacrylate.
6. The ion conducting polymer feedstock material of claim 1 , wherein the ion conducting polymer feedstock material further comprises a viscosity-increasing agent selected from the group of cellulose, cellulose acetate, cellulose triacetate, cellulose propionate acetate, or ethyl cellulose.
7. The ion conducting polymer feedstock material of claim 1 , further comprising a cross-linking catalyst wherein the cross-linking catalyst comprises a Lewis acid or a Brönsted acid in an amount sufficient to initiate polymerization of the monomer.