Thin film battery and method of manufacture

• US 20050130032A1
• Filed: 12/07/2004
• Published: 06/16/2005
• Est. Priority Date: 09/07/2000
• Status: Active Grant

• Current Assignee: Front Edge Technology, Inc (KLA Corporation)
• Original Assignee: Front Edge Technology, Inc (KLA Corporation)
• Inventors: Nieh, Kai-Wei, Krasnov, Victor, Ting, Su-Jen
• Granted Patent: US 7,186,479 B2
• Time in Patent Office: Days
• US Class Current: 429/152
• CPC Class Codes: H01M 10/0436 Small-sized flat cells or batteries for portable equipment
• CPC Class Codes: H01M 10/052 Li-accumulators
• CPC Class Codes: H01M 10/0562 Solid materials
• CPC Class Codes: H01M 10/058 Construction or manufacture
• CPC Class Codes: H01M 10/0585 of accumulators having only flat construction elements, i.e. flat positive electrodes, flat negative electrodes and flat separators
• CPC Class Codes: H01M 4/04 Processes of manufacture in general
• CPC Class Codes: H01M 4/0402 Methods of deposition of the material
• CPC Class Codes: H01M 4/0404 by coating on electrode collectors
• CPC Class Codes: H01M 4/0423 Physical vapour deposition
• CPC Class Codes: H01M 4/0426 Sputtering
• CPC Class Codes: H01M 4/0471 involving thermal treatment, e.g. firing, sintering, backing particulate active material, thermal decomposition, pyrolysis
• CPC Class Codes: H01M 4/131 Electrodes based on mixed oxides or hydroxides, or on mixtures of oxides or hydroxides, e.g. LiCoOx
• CPC Class Codes: H01M 4/1391 of electrodes based on mixed oxides or hydroxides, or on mixtures of oxides or hydroxides, e.g. LiCoOx
• CPC Class Codes: H01M 4/525 of mixed oxides or hydroxides containing iron, cobalt or nickel for inserting or intercalating light metals, e.g. LiNiO2, LiCoO2 or LiCoOxFy
• CPC Class Codes: H01M 4/5815 Sulfides
• CPC Class Codes: H01M 4/5825 Oxygenated metallic salts or polyanionic structures, e.g. borates, phosphates, silicates, olivines
• CPC Class Codes: H01M 4/661 Metal or alloys, e.g. alloy coatings H01M4/669 take precedence
• CPC Class Codes: H01M 4/662 Alloys collectors of lead alloys H01M4/685
• CPC Class Codes: H01M 4/70 characterised by shape or form
• CPC Class Codes: H01M 4/75 Wires, rods or strips
• CPC Class Codes: H01M 50/46 : Separators, membranes or diaphragms characterised by their combination with electrodes
• CPC Class Codes: H01M 6/40 : Printed batteries , e.g. thin film batteries
• CPC Class Codes: Y02E 60/10 : Energy storage using batteries
• CPC Class Codes: Y02P 70/50 : Manufacturing or production processes characterised by the final manufactured product
• CPC Class Codes: Y10T 29/49108 : Electric battery cell making
• CPC Class Codes: Y10T 29/49115 : including coating or impregnating

Abstract

A thin film battery comprises a substrate with a front side and a back side. A first battery cell is provided on the front side of the substrate, the first battery cell including an electrolyte between a pair of electrodes. A second battery cell is provided on the back side of the substrate, the second battery cell also including an electrolyte between a pair of electrodes. The battery is capable of providing an energy density of more than 700 wh/l and a specific energy of more than 250 wh/kg. A method of annealing a deposited thin film is also described.

Claims

1. A thin film battery comprising:

(a) a substrate having a front side and a back side;

(b) a first battery cell on the front side of the substrate, the first battery cell comprising an electrolyte between a pair of electrodes; and

(c) a second battery cell on the back side of the substrate, the second battery cell comprising an electrolyte between a pair of electrodes,

whereby the battery is capable of providing an energy density of more than 700 wh/l and a specific energy of more than 250 wh/kg.

2. A battery according to claim 1 wherein substrate comprises mica.

3. A battery according to claim 2 wherein substrate comprises a thickness of less than about 100 microns.

4. A battery according to claim 3 wherein the substrate comprises a thickness of less than about 25 microns.

5. A battery according to claim 1 wherein at least one of each pair of electrodes comprises crystalline lithium metal oxide.

6. A battery according to claim 1 wherein both electrolytes comprise amorphous lithium phosphorus oxynitride.

7. A battery according to claim 1 comprising an adhesion layer on the front side and back side of the substrate.

8. A battery according to claim 7 comprising a current collector on each adhesive layer.

9. A thin film battery comprising:

(a) a mica substrate having a front side, a back side, and a thickness of less than about 100 microns;

(b) a first battery cell on the front side of the substrate, the first battery cell comprising an electrolyte between a pair of electrodes; and

(c) a second battery cell on the back side of the substrate, the second battery cell comprising an electrolyte between a pair of electrodes,

wherein the battery is capable of providing an energy density of more than 700 wh/l and a specific energy of more than 250 wh/kg.

10. A battery according to claim 9 wherein the mica substrate comprises a thickness of less than about 25 microns.

11. A battery according to claim 9 wherein at least one of each pair of electrodes comprises crystalline lithium metal oxide.

12. A battery according to claim 9 wherein both electrolytes comprise amorphous lithium phosphorus oxynitride.

13. A battery according to claim 9 comprising (i) an adhesion layer on the front side and back side of the substrate, and (ii) a current collector on each adhesive layer.

14. A thin film battery comprising:

(a) a mica substrate comprising a front side and back side;

(b) a first battery cell on the front side of the mica substrate, the first battery cell comprising;

(i) an anode,

(ii) a cathode comprising crystalline lithium metal oxide, and

(iii) an electrolyte between the anode and cathode, the electrolyte comprising lithium phosphorus oxynitride,

(c) a second battery cell on the back side of the mica substrate, the second battery cell comprising;

(i) an anode,

(ii) a cathode comprising crystalline lithium metal oxide, and

(iii) an electrolyte between the anode and cathode, the electrolyte comprising lithium phosphorus oxynitride.

15. A battery according to claim 14 wherein the mica substrate comprises a thickness of less than about 25 microns.

16. A battery according to claim 14 comprising an adhesion layer on the mica substrate.

17. A battery according to claim 14 further comprising an anode current collector in contact with the anode, and a cathode current collector in contact with the cathode.

18. A battery according to claim 14 wherein the cathode comprises crystalline LiCoO₂.

19. A battery according to claim 14 wherein the electrolyte comprises amorphous lithium phosphorus oxynitride.

20. A method of manufacturing a thin film battery comprising:

(a) placing a mica substrate in a chamber and setting conditions in the chamber to deposit a thin film on the mica substrate, the thin film comprising at least one of an electrode and electrolyte; and

(b) annealing the deposited thin film by heating the mica substrate to a temperature from about 150 to about 600°

C.

21. A method according to claim 20 wherein the annealing step was performed to eliminate defects in the deposited thin film such that battery capacity increases by 10 to 20% and the charge and discharge current increases by more than 50%.

22. A method according to claim 20 wherein the annealing step was performed to reduce electrical contact resistances in the deposited thin film such that battery capacity increases by 10 to 20% and the charge and discharge current increases by more than 50%.

23. A method according to claim 20 comprises forming on the mica substrate, thin films comprising first and second current collectors and a pair of electrodes comprising an anode and cathode about the electrolyte.

24. A method according to claim 20 wherein (a) comprises:

(a) providing a target comprising LiCoO₂ in the chamber;

(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/cm² to the target, thereby sputtering material from the target to deposit onto the substrate; and

(d) exhausting the process gas from the chamber.

25. A method according to claim 24 wherein the chamber comprises a magnetron-sputtering cathode, and the method comprises energizing the process gas by applying a potential across the target and a 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/cm².

26. A method according to claim 24 comprises maintaining the substrate at a potential of from about −

5 to about −

200 V. A m.

27. A method according to claim 24 further comprising applying a non-uniform magnetic field about the target in the chamber comprising a weaker central magnetic field strength and a surrounding stronger peripheral magnetic field strength.