Barrier for thin film lithium batteries made on flexible substrates and related methods
A thin film solid state battery configured with barrier regions formed on a flexible substrate member and method. The method includes forming a bottom thin film barrier material overlying and directly contacting a surface region of a substrate. A first current collector region can be formed overlying the bottom barrier material and forming a first cathode material overlying the first current collector region. A first electrolyte can be formed overlying the first cathode material, and a second current collector region can be formed overlying the first anode material. The method also includes forming an intermediary thin film barrier material overlying the second current collector region and forming a top thin film barrier material overlying the second electrochemical cell. The solid state battery can comprise the elements described in the method of fabrication.
1. A solid state battery device comprising:
a substrate;
a bottom thin film barrier material over the substrate, wherein the bottom thin film barrier material is configured to prevent ionic species from an anode from migrating to the substrate;
a first electrochemical cell comprising a first current collector, a second current collector, a cathode, an electrolyte, and the anode, wherein the first electrochemical cell is on top of the bottom thin film barrier material;
an intermediary thin film barrier material over the first electrochemical cell, the intermediary thin film barrier material comprises an oxide of metal or metalloid, a nitride of metal or metalloid, a carbide of metal or metalloid, or a phosphate of metal;
a second electrochemical cell over the intermediary thin film barrier material, wherein the intermediary thin film barrier material is configured to prevent migration of an ionic species from at least the first electrochemical cell to the second electrochemical cell or the second electrochemical cell to the first electrochemical cell; and
a top thin film barrier material over the second electrochemical cell, wherein the top thin film barrier material covers the first electrochemical cell and the second electrochemical cell,
wherein an exposed region is formed within a portion of the top thin film barrier material to expose a first contact region on a topmost surface of the first current collector and a second contact region on a topmost surface of the second current collector of the solid state battery device;
wherein the topmost surface of the first current collector and the topmost surface of the second current collector are perpendicular to a direction in which the intermediary thin film barrier material, second electrochemical cell, and top thin film barrier material are stacked onto the substrate.
2. The device of claim 1 , wherein the ionic species comprises a lithium ion.
3. The device of claim 1 , further comprising one or more electrochemical cells configured between the second electrochemical cell and the top thin film barrier material.
4. The device of claim 1 , wherein the bottom thin film barrier material and the top thin film barrier material each comprise one or more of an oxide of metal or metalloid, a nitride of metal or metalloid, a carbide of metal or metalloid, and a phosphate of metal.
5. The device of claim 1 , wherein the bottom thin film barrier material, the intermediary thin film barrier material, and the top thin film barrier material are provided by physical vapor deposition including one or more of sputtering, thermal evaporation, and e-beam evaporation.
6. The device of claim 1 , wherein the bottom thin film barrier material, the intermediary thin film barrier material, and the top thin film barrier material each have a thickness of about 30 nm to about 100 nm.
7. The device of claim 1 , wherein the substrate comprises a copper material, an aluminum material, or a polymer material.
8. The device of claim 1 , wherein the intermediary thin film barrier material is configured to planarize an upper surface region of the first electrochemical cell.
9. The device of claim 1 , wherein the intermediary thin film barrier material is configured in a compressive or tensile mode to compensate a strain of the first electrochemical cell.
10. The device of claim 1 , further comprising a polymer-based coating material configured to enclose the first electrochemical cell and the second electrochemical cell.
11. The device of claim 1 , wherein the top thin film barrier material is configured to prevent one or more of an oxygen species, a water species, a nitrogen species, and a carbon dioxide species from diffusing into at least the second electrochemical cell or the first electrochemical cell.