Cathode for thin film microbattery
A battery comprising an anode comprising anode material in contact with a metal anode current collector. The battery further comprises a cathode comprising cathode material in contact with a cathode current collector comprising a transparent conducting oxide (TCO). The battery further comprises an electrolyte with a pH in a range of 3 to 7.
1. A battery comprising:
a first polymer flex substrate;
an anode comprising an anode material in contact with a metal anode current collector, wherein the metal anode current collector of the anode is adhered to a surface of the first polymer flex substrate by a first adhesion metal layer;
a cathode comprising a conducting cathode material in contact with a cathode current collector comprising a transparent conducting oxide (TCO);
a second polymer flex substrate, wherein the transparent conducting oxide TCO is adhered to a surface of the second polymer flex substrate by a second adhesion metal layer;
an electrolyte with a pH in a range of 3 to 7 located between the anode and the cathode; and
a polymer bondable seal material surrounding the conducting cathode material, the electrolyte and the anode material.
2. The battery of claim 1 , wherein the transparent conducting oxide (TCO) comprises one or more of the following: indium tin oxide (ITO), indium zinc oxide (IZO), Al-doped zinc oxide (AZO), and Ga-doped zinc oxide (GZO).
3. The battery of claim 1 , wherein the conducting cathode material is MnO 2 .
4. The battery of claim 1 , wherein the electrolyte is an aqueous solution.
5. The battery of claim 1 , wherein the electrolyte is a gel.
6. The battery of claim 1 , wherein the electrolyte comprises one or more of the following: zinc chloride, zinc acetate, and ammonium chloride.
7. The battery of claim 1 , wherein the battery has a volume less than 1 cubic mm.
8. The battery of claim 1 , wherein a thickness of the cathode current collector is in a range of 20 nm to 200 nm.
9. The battery of claim 1 , wherein the battery has a flexibility defined by a radius of curvature of between about 4 mm and about 20 mm.
10. The battery of claim 1 , wherein the battery has a thickness of less than about 150 microns.
11. The battery of claim 1 , wherein the battery has an open circuit voltage of between 1.4V and 1.8V and has a discharge capacity of between 10 uA-hours and 200 uA-hours.
12. The battery of claim 1 , wherein the conducting cathode material is one or more of the following: electroplated nickel hydroxide; and a mixture MnO 2 with a binder.
13. The battery of claim 1 , wherein the anode material is electroplated Zn on the anode current collector that comprises one or more of the following: Sn, In, Ni, and an alloy thereof.
14. The battery of claim 1 , wherein the battery has a shape of an arc.
15. The battery of claim 1 , wherein a potential for an onset of hydrogen evolution as measured on a cyclic voltammetry curve is less than −1.6V relative to Hg/HgO for a KOH solution.
16. The battery of claim 1 , wherein the first and second adhesion metal layers are selected from Ti, Ta and TiW.
17. The battery of claim 1 , wherein the first adhesion metal layer is present only on a portion of the first polymer flex substrate, and wherein the second adhesion layer is present only on a portion of the second polymer flex substrate.
18. The battery of claim 17 , wherein a portion of the polymer bondable seal material contacts a portion of the transparent conducting oxide (TCO), and wherein another portion of the bondable seal material contacts a portion of the metal anode current collector.