Thin-film batteries with polymer and LiPON electrolyte layers and method
A method and apparatus for making thin-film batteries having composite multi-layered electrolytes with soft electrolyte between hard electrolyte covering the negative and/or positive electrode, and the resulting batteries. In some embodiments, foil-core cathode sheets each having a cathode material (e.g., LiCoO 2 ) covered by a hard electrolyte on both sides, and foil-core anode sheets having an anode material (e.g., lithium metal) covered by a hard electrolyte on both sides, are laminated using a soft (e.g., polymer gel) electrolyte sandwiched between alternating cathode and anode sheets. A hard glass-like electrolyte layer obtains a smooth hard positive-electrode lithium-metal layer upon charging, but when very thin, have randomly spaced pinholes/defects. When the hard layers are formed on both the positive and negative electrodes, one electrode's dendrite-short-causing defects on are not aligned with the other electrode's defects. The soft electrolyte layer both conducts ions across the gap between hard electrolyte layers and fills pinholes.
1. A method comprising: providing an anode component comprising a first sheet that includes an anode material and a first LiPON layer covering the anode material and having randomly spaced defects; providing a cathode component comprising a second sheet that includes a cathode material that includes lithium and a second LiPON layer covering the cathode material and having randomly spaced defects; and sandwiching a polymer electrolyte material between the LiPON layer covering the anode material of the first sheet and the LiPON layer covering the cathode material of the second sheet, wherein the polymer electrolyte material includes a gel and at least partially fills and fixes the randomly spaced defects in the first and second LiPON layers.
2. The method of claim 1 , further comprising: providing a third sheet that includes an anode material and a third LiPON layer covering the anode material; providing a fourth sheet that includes a cathode material that includes lithium and a fourth LiPON layer covering the cathode material; sandwiching a polymer electrolyte material between the LiPON layer covering the anode material of the third sheet and the LiPON layer covering the cathode material of the fourth sheet; and sandwiching a polymer electrolyte material between the LiPON layer covering the anode material of the third sheet and the LiPON layer covering the cathode material of the second sheet.
3. The method of claim 1 , wherein the anode material of the first sheet is deposited as a lithium-metal layer on a copper anode-current-collector layer through the LiPON layer.
4. The method of claim 3 , wherein the deposition of a lithium anode is done by electroplating in a propylene carbonate/lithium-salt electrolyte solution prior to assembling the cell.
5. The method of claim 1 , wherein the first sheet includes a cathode material on a face opposite the anode material and a LiPON layer covering the cathode material, and the second sheet includes an anode material on a face opposite the cathode material and a LiPON layer covering the anode material; the method further comprising: providing a third sheet that includes an anode material and a LiPON layer covering the anode material on a first face, and a cathode material that includes lithium and a LiPON layer covering the cathode material on a second face opposite the first face; and sandwiching the polymer electrolyte material between the LiPON layer covering the anode material of the third sheet and the UPON layer covering the cathode material of the second sheet.
6. The method of claim 1 , wherein the polymer electrolyte layer includes a polyvinylidene difluoride, propylene carbonate, and a lithium salt.
7. The method of claim 1 , further comprising the step of laminating two or more battery cells together to form a laminated battery device.
8. The method of claim 1 , wherein the laminated battery device comprises a stack of two-sided anode current collectors and two-sided cathode current collectors that are connected in parallel.
9. The method of claim 1 , wherein the laminated battery device comprises a stack of two-sided anode current collectors and two-sided cathode current collectors that are connected in series.
10. The method of claim 1 , wherein the polymer electrolyte layer is an adhesive that provides a structural connection between the LiPon layers.
11. The method of claim 1 , wherein the anode component comprises a current collector onto which is deposited a cathode material.
12. The method of claim 1 , wherein the anode component further comprises a current collector, and wherein a layer of lithium is formed as an active portion of the cathode component after assembly of the battery cell.
13. The method of claim 1 , wherein the polymer electrolyte layer is sticky.
14. The method of claim 1 , wherein the polymer electrolyte layer comprises polyvinylidene difluoride, propylene carbonate, and a lithium salt.
15. The method of claim 1 , wherein the polymer electrolyte layer comprises MEEP.
16. The method of claim 1 , wherein the negative electrode component includes a negative-electrode current collector made of a metal that does not readily alloy with lithium during a plating operation, and lithium metal is plated onto the negative-electrode current collector through the LiPON layer on the negative electrode component.
17. The method of claim 1 , wherein the polymer electrolyte layer comprises a polyphosphazene and a lithium salt.