Method of fabricating thin film battery with annealed substrate
View Patent ↗A thin film battery manufacturing method comprises annealing a battery substrate to a temperature at which organic materials are burned off the battery substrate to clean the battery substrate. The battery substrate comprises a thickness of less than about 100 microns. After annealing, a plurality of thin films are formed on the annealed battery substrate, the thin films comprising at least one electrolyte between a pair of electrodes, and the thin films adapted to generate or store an electrical charge. The thin films can also be annealed to remove defects in the thin films.
1. A thin film battery manufacturing method comprising:
(a) annealing a battery substrate comprising mica to a temperature at which organic materials are burned off the battery substrate to clean the battery substrate, the battery substrate comprising a thickness of less than about 100 microns; and
(b) forming a plurality of thin films on the annealed battery substrate, the thin films comprising at least one electrolyte between a pair of electrodes, and the thin films adapted to generate or store an electrical charge.
2. A method according to claim 1 comprising annealing the battery substrate by heating the battery substrate in air to about 400° C.
3. A method according to claim 1 comprising annealing the battery substrate by heating the battery substrate to a temperature from about 150 to about 600° C.
4. A method according to claim 3 comprising annealing the battery substrate by heating the battery substrate for about 10 minutes.
5. A method according to claim 1 further comprising annealing the battery substrate by heating the battery substrate to a temperature that is sufficiently high to eliminate defects.
6. A method according to claim 1 wherein the battery substrate comprises a thickness of less than 25 microns.
7. A method according to claim 1 comprising forming the thin films on the battery substrate by physical or chemical vapor deposition, oxidation, nitridation or electro-plating.
8. A method according to claim 1 comprising heating the battery substrate to a temperature that is sufficiently high to eliminate defects in the thin films formed on the battery substrate such that battery capacity increases by 10 to 20% and the charge and discharge current increases by more than 50%.
9. A method according to claim 1 wherein (b) comprises:
(a) placing the battery substrate in a chamber comprising a target composed of LiCoO 2 ;
(b) introducing a process gas into the chamber;
(c) energizing the process gas by applying a current at a power density level of from about 0.1 to about 20 W/cm 2 to the target, thereby sputtering material from the target to deposit onto the battery substrate; and
(d) exhausting the process gas from the chamber.
10. A method according to claim 9 wherein the chamber comprises a magnetron-sputtering cathode, and the method comprises energizing the process gas by applying a potential across the target and the magnetron-sputtering cathode to form a plasma of the process gas that has an ion flux of from about 0.1 to about 5 mA/cm 2 .
11. A method according to claim 9 comprising maintaining the battery substrate at a potential of from about −5V to about −200 V.
12. A method according to claim 9 further comprising applying a non-uniform magnetic field about the target in the chamber, the non-uniform magnetic field comprising a weaker central magnetic field strength and a surrounding stronger peripheral magnetic field strength.
13. A thin film battery manufacturing method comprising:
(a) depositing a thin film on a battery substrate comprising mica, the battery substrate comprising a thickness of less than 100 microns, and the thin film comprising an electrode; and
(b) annealing the thin film by heating the substrate to a temperature from about 150 to about 600° C., and that is sufficiently high to eliminate defects from the thin film.
14. A method according to claim 13 comprising forming the thin film on the battery substrate by physical or chemical vapor deposition, oxidation, nitridation or electro-plating.
15. A method according to claim 13 comprising annealing the battery substrate to a temperature that is sufficiently high to eliminate defects in the thin films such that battery capacity increases by 10 to 20% and the charge and discharge current increases by more than 50%.
16. A thin film battery manufacturing method comprising:
(a) annealing a battery substrate comprising mica to a temperature at which organic materials are burned off the battery substrate to clean the battery substrate, the battery substrate comprising a thickness of less than about 100 microns;
(b) forming a thin film on the annealed battery substrate, the thin films comprising an electrode; and
(c) annealing the thin film by heating the substrate to a temperature from about 150 to about 600° C., and that is sufficiently high to eliminate defects from the thin film.