3D patterned alkali-metal or alloy anode

Abstract

Energy storage devices and methods and apparatus for manufacturing energy storage devices including patterned electrodes are provided. A flexible support layer having a lithium film formed thereon is exposed to a laser lift-off process. During the laser lift-off process, a laser is directed through the flexible support layer to activate an interface of the lithium film and the flexible support layer, for example, at a Li-PET interface. The laser can be directed through the backside of the flexible support layer stack, for example, from the plastic containing substrate or PET side. Exposure to the laser can pattern the lithium film by creating a void volume between the lithium film and the flexible support layer. The void volume can make subsequent separation of the lithium film from the flexible support layer easier during removal of the flexible support layer from the lithium film.

Description

3D PATTERNED ALKALI-METAL OR ALLOY ANODEBACKGROUNDField

[0001] The present disclosure generally relates to energy storage devices and methods and apparatus for manufacturing energy storage devices. More particularly, the present disclosure generally relates to patterned electrodes and methods and apparatus for forming patterned electrodes.Description of the Related Art

[0002] Rechargeable energy storage devices are currently becoming increasingly essential for many fields of everyday life. High-capacity energy storage devices incorporating alkali metals, such as lithium-ion (Li-ion) batteries, are used in a growing number of applications, including portable electronics, medical, transportation, grid- connected large energy storage, renewable energy storage, and uninterruptible power supply (UPS).

[0003] Therefore, there is a need for electrodes incorporating alkali metals and methods and apparatus for the deposition and processing of alkali metals used in energy storage devices.SUMMARY

[0004] The present disclosure generally relates to energy storage devices and methods and apparatus for manufacturing energy storage devices. More particularly, the present disclosure generally relates to patterned electrodes and methods and apparatus for forming patterned electrodes.

[0005] In one aspect, a method of making an electrode is provided. The method includes transferring a flexible support layer stack including a flexible support layer and an alkali metal film formed over the flexible support layer to a flexible substrate stack, the flexible substrate stack including a current collector substrate. The method further includes patterning the alkali metal film by exposing the alkali metal film to a laser beam, the laser beam directed toward a backside of the flexible support layer. The method further includes removing the flexible support layer to form a patterned electrode structure.

[0006] Implementations may include one or more of the following. Exposing the alkali metal film to the laser beam induces a lithium transfer process creating a void volume between the alkali metal film and the flexible support layer. The laser beam is produced by an infrared laser source. The laser beam is a continuous laser beam produces by a solid-state laser source. The laser beam is a pulsed laser beam produced by a solid-state laser. The flexible substrate stack further includes a lithiophilic film formed over the current collector substrate. The flexible support layer stack further includes a release layer formed in between the flexible support layer and the alkali metal film. The flexible support layer comprises a material selected from polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polyimide (PI), poly(methyl methacrylate) (PMMA), cellulose tri-acetate (TAC), polypropylene (PP), polyethylene (PE), polycarbonates (PC), multilayers thereof, or a combination thereof. The lithiophilic film is selected from Al, Au, Ag, Bi, Pt, Zn, Si, Sn, Mg, In, Ga, or Cu, alloys thereof. The lithiophilic film is selected from Li4Ti5O12, Lio.388Tao.238Lao.475Cl3, XLi2O-MCIy, wherein M = Ta, Hf, 0.8<x<2, and y = 4 or 5, LnOCI, wherein Ln= rare earth metal, RENiO3, AIOx, CuO, ZnO, CoO, or MnO. The alkali metal is lithium. Transferring the release layer, the electrolyte containing layer, the one or more interface layers, and the alkali metal to a substrate to form an anode film stack comprises a lamination process. A battery incorporating the electrode made according to the aforementioned method.

[0007] In one or more implementations, a method of making an electrode is provided. The method includes transferring a flexible support layer stack including a flexible support layer and an alkali metal film formed over the flexible support layer to a flexible substrate stack, the flexible substrate stack including a current collector substrate. The method further includes patterning the alkali metal film by exposing the alkali metal film to a laser beam, the laser beam directed toward a backside of the flexible support layer. The method further includes removing the flexible support layer to form a patterned electrode structure.

[0008] Implementations may include one or more of the following. Exposing the alkali metal film to the laser beam induces an alkali metal transfer process creating a void volume between the alkali metal film and the flexible support layer. The laser beam is produced by an infrared laser source. The laser beam is a continuous laser beam produces by a solid-state laser source. The laser beam is a pulsed laser beamproduced by a solid-state laser. The flexible substrate stack further includes a lithiophilic film formed over the current collector substrate. The lithiophilic film is selected from Al, Au, Ag, Bi, Pt, Zn, Si, Sn, Mg, In, Ga, or Cu, alloys thereof. The lithiophilic film is selected from Li4Ti5O12, Lio.388Tao.238Lao.475Cl3, XLi20-MCIy, wherein M = Ta, Hf, 0.8<x<2, and y = 4 or 5, LnOCI, wherein Ln= rare earth metal, RENiO3, AIOx, CuO, ZnO, CoO, or MnO. The flexible support layer stack further includes a release layer formed in between the flexible support layer and the alkali metal film. The flexible support layer includes a material selected from polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polyimide (PI), poly(methyl methacrylate) (PMMA), cellulose tri-acetate (TAC), polypropylene (PP), polyethylene (PE), polycarbonates (PC), multilayers thereof, or a combination thereof. The alkali metal film is lithium.

[0009] In one or more implementations, an anode structure is provided. The anode structure includes a current collector, a lithiophilic film formed over the current collector, and a patterned alkali metal film formed over the lithiophilic film. The patterned alkali metal film defines a plurality of void volumes separated by the patterned alkali metal film, the void volumes defined by sidewalls of the patterned alkali metal film and a bottom surface. The anode structure further includes an alkali metal film deposited into the void volumes of the patterned alkali metal film.

[0010] Implementations may include one or more of the following. The lithiophilic film defines the bottom surface. The sidewalls of the patterned alkali metal film define a honeycomb structure. The lithiophilic film is selected from Al, Au, Ag, Bi, Pt, Zn, Si, Sn, Mg, In, Ga, or Cu, alloys thereof. The lithiophilic film is selected from Li4Ti5O12, Lio.388Tao.238Lao.475Cl3, XLi2O-MCIy, wherein M = Ta, Hf, 0.8<x<2, and y = 4 or 5, LnOCI, wherein Ln= rare earth metal, RENiO3, AIOx, CuO, ZnO, CoO, or MnO. The alkali metal film is lithium. The patterned alkali metal film is lithium.

[0011] In one or more implementations, an energy storage device is provided. The energy storage device includes a cathode electrode structure and an anode structure. The anode structure includes a current collector, a lithiophilic film formed over the current collector, and a patterned alkali metal film formed over the lithiophilic film. The patterned alkali metal film defines a plurality of void volumes separated by the patterned alkali metal film, the void volumes defined by sidewalls of the patternedalkali metal film and a bottom surface. The anode structure further includes an alkali metal film deposited into the void volumes of the patterned alkali metal film.

[0012] Implementations may include one or more of the following. The lithiophilic film defines the bottom surface. The sidewalls of the patterned alkali metal film define a honeycomb structure. The lithiophilic film is selected from Al, Au, Ag, Bi, Pt, Zn, Si, Sn, Mg, In, Ga, or Cu, alloys thereof. The lithiophilic film is selected from Li4Ti5O12, Lio.388Tao.238Lao.475Cl3, XLi2O-MCIy, wherein M = Ta, Hf, 0.8<x<2, and y = 4 or 5, LnOCI, wherein Ln= rare earth metal, RENiO3, AIOx, CuO, ZnO, CoO, or MnO. The alkali metal film is lithium. The patterned alkali metal film is lithium. The energy storage device further includes a separator film. The cathode electrode structure includes a cathode film and a cathode current collector.

[0013] In one or more implementations, a method of making an electrode is provided. The method includes transferring a flexible support layer stack including a flexible support layer and a first alkali metal film formed over the flexible support layer to a flexible substrate stack. The flexible substrate stack including a current collector substrate and a lithiophilic film formed over the current collector substrate. The method further includes patterning the first alkali metal film by exposing the first alkali metal film to a laser beam, the laser beam directed toward a backside of the flexible support layer. The method further includes removing the flexible support layer to form a patterned alkali metal film. The patterned alkali metal film defines a plurality of void volumes separated by the patterned alkali metal film, the void volumes defined by sidewalls of the patterned alkali metal film and a bottom surface. The method further includes depositing an alkali metal film into the void volumes via an electroplating process.

[0014] Implementations may include one or more of the following. The lithiophilic film defines the bottom surface of the void volumes. The sidewalls of the patterned alkali metal film define a honeycomb structure. The lithiophilic film is selected from Al, Au, Ag, Bi, Pt, Zn, Si, Sn, Mg, In, Ga, or Cu, alloys thereof. The lithiophilic film is selected from Li4Ti5O12, Lio.388Tao.238Lao.475Cl3, XLi2O-MCIy, wherein M = Ta, Hf, 0.8<x<2, and y = 4 or 5, LnOCI, wherein Ln= rare earth metal, RENiO3, AIOx, CuO, ZnO, CoO, or MnO. The alkali metal film is lithium. The patterned alkali metal film is lithium.

[0015] In another aspect, a non-transitory computer readable medium has stored thereon instructions, which, when executed by a processor, causes the process to perform operations of the above apparatus and / or method.BRIEF DESCRIPTION OF THE DRAWINGS

[0016] So that the manner in which the above recited features of the present disclosure can be understood in detail, a more particular description of the disclosure, briefly summarized above, may be had by reference to implementations, some of which are illustrated in the appended drawings. It is to be noted, however, that the appended drawings illustrate only exemplary implementations and are therefore not to be considered limiting of its scope, and may admit to other equally effective implementations.

[0017] FIG. 1A illustrates a schematic cross-sectional view of an energy storage device incorporating an anode structure having a patterned anode film formed in accordance with one or more implementations of the present disclosure.

[0018] FIG. 1 B illustrates a cross-sectional view of a dual-sided anode electrode structure having a patterned anode film formed in accordance with one or more implementations of the present disclosure.

[0019] FIG. 2 illustrates a flowchart showing selected operations of a method of forming an energy storage device incorporating a patterned anode film in accordance with one or more implementations of the present disclosure.

[0020] FIGS. 3A-3E illustrate views of various stages of manufacturing an energy storage device according to the method of FIG. 2 in accordance with one or more implementations of the present disclosure.

[0021] FIGS. 4A and 4B illustrate view of various stages of manufacturing an energy storage device using a laser lift-off process in accordance with one or more implementations of the present disclosure.

[0022] FIG. 5 illustrates an SEM image of a patterned anode film formed in accordance with one or more implementations of the present disclosure.

[0023] FIG. 6 illustrates another SEM image of a patterned anode film formed in accordance with one or more implementations of the present disclosure.

[0024] FIG. 7 illustrates another SEM image of a patterned anode film including lithium nucleation formed in accordance with one or more implementations of the present disclosure.

[0025] FIG. 8 illustrates another SEM image of a patterned anode film after lithium plating nucleation formed in accordance with one or more implementations of the present disclosure.

[0026] To facilitate understanding, identical reference numerals have been used, where possible, to designate identical elements that are common to the figures. It is contemplated that elements and features of one implementation may be beneficially incorporated in other implementations without further recitation.DETAILED DESCRIPTION

[0027] The present disclosure generally relates to energy storage devices and methods and apparatus for manufacturing energy storage devices. More particularly, the present disclosure generally relates to patterned electrodes and methods and apparatus for forming patterned electrodes.

[0028] In one or more implementations, which can be combined with other implementations, 3D structured alkali metal or alloy anodes and methods for manufacturing the same are provided. Alkali metals, for example, lithium metal, are typically plated at lower current density to reduce or prevent dendritic growth. Buffer lithium is used to replenish inventory loss from cycling of the cell. The 3D structured alkali metal or alloy anodes described are designed to accommodate local volume change and plating of columnar structure. The base of the columnar structure has an electrophilic coating so that alkali metal plating and stripping preferentially occurs from the columnar base. The pattern of the 3D structured anodes can be structured like a honeycomb for maximum volume fraction accommodation of plated alkali metal. With the higher surface area provided by the patterned 3D structured anodes, plating and / or stripping current density can be increased. By making the 3D patterned anode structure on a current collector with a lithiophilic coating, lithium can be preferentially deposited onto the pit or crater defined by the 3D patterned anode structure whereoverpotential is low. In addition, the base of the lithium reservoir can be capped with dielectric polymer to prevent degradation of the buffer lithium at the base of the columnar structure. By fabricating a 3D patterned anode structure, for example, a honeycomb structure, which defines a lithium reservoir on top of a thin current collector (e.g., Cu, SS, Ni etc., Metallized plastic) and a lithiophilic layer the 3D patterned alkali metal or alloy anode provides superior performance (rate and volume change). Creating a columnar plating and stripping structure provides better rate capability for hybrid solid state battery. The lithium reservoir at the base of the columnar structure supplements inventory loss during cycling. The volume change in the cell can be locally mitigated since the columnar structure helps locally expand plated lithium. External stack pressure can also be decreased compared to the state of art lithium anode cell designs. In addition, in contrast with mesh current collector or porous current collector concepts that have been proposed for lithium metal anode design, the 3D patterned alkali metal or alloy anode can be used to form thinner, light weight electrodes, which can also be planar.

[0029] In one or more implementations, which can be combined with other implementations, the 3D structured alkali metal or alloy anodes are formed using a laser lift-off process. The laser lift-off process provides for patterned removal of lithium. The patterned removal of lithium creates the 3D structure of the patterned anode. In one or more implementations, an IR fiber laser is used to activate the flexible support layer-Li interface, for example, the PET-Li interface, from the flexible support layer side. Lithium at the activated flexible support layer-Li interface may be subsequently released from the flexible support layer during removal of the flexible support layer.

[0030] In one or more implementations, which can be combined with other implementations, the laser lift-off process or laser activation process described can be incorporated into a roll-to-roll tool and used in a roll-to-roll process. The laser activation process enables transfer of patterned lithium from a plastic substrate onto a current collector by exposing an interface between the lithium metal layer and the flexible support layer, for example, the Li-PET interface, to a laser which induces lithium transfer at the interface. This interface between the lithium metal layer and the flexible support layer may also include a release layer as described.

[0031] In one or more implementations, which can be combined with other implementations, the laser lift-off process enables the patterning of the flexible support layer stack (e.g., the flexible support layer and lithium metal layer). Any suitable pattern may be achieved, for example, a square, a triangle, a circle, a honeycomb structure, etc.

[0032] In one or more implementations, which can be combined with other implementations, the laser lift-off process can use a laser source to create an interface reaction with either a release layer, an interface layer, or both the release layer and the interface layer between the lithium metal layer and the flexible support layer, for example, PET, to enable subsequent removal of the flexible support layer from the lithium metal layer at the activated interface.

[0033] In one or more implementations, which can be combined with other implementations, a flexible support layer stack is provided. The flexible support layer stack can include a plastic containing substrate, for example, a polyethylene terephthalate (PET) substrate. The flexible support layer stack can further include a release layer, for example, silicone or other deposited release layers, formed on the flexible support layer stack. An alkali metal-containing layer, for example, a lithium metal layer is formed over the flexible support layer stack. In implementations where the release layer is not present, the lithium metal layer can be formed directly on the plastic containing substrate. In implementations where the release layer is present, the lithium metal layer can be formed directly on the release layer. The flexible support layer having the lithium metal layer formed thereon is exposed to a laser lift-off process. In one or more implementations, during the laser lift-off process, a laser is directed through the flexible support layer to activate the interface of the lithium metal layer and the flexible support layer, for example, at the Li-PET interface. The laser can be directed through the backside of the flexible support layer stack, for example, from the plastic containing substrate or PET side. Exposure to the laser can create a void volume between the lithium metal layer and the flexible support layer. This void volume can make subsequent separation of the lithium metal layer from the flexible support layer easier during removal of the flexible support layer from the lithium metal layer. In addition, precise laser beam position control enables the selective removal of lithium metal to form various shapes of the lithium metal layer on the current collector. Further, exposure to the laser can be used to pattern the lithium metal layersuch that a precise pattern of lithium metal is removed from the flexible support layer stack.

[0034] It is noted that while the particular substrate on which some implementations described herein can be practiced is not limited, it is particularly beneficial to practice the implementations on flexible substrates, including for example, web-based substrates, panels and discrete sheets. The flexible substrate can also be in the form of a foil, a polymer film, or a thin plate.

[0035] It is also noted here that a flexible substrate or web as used within the implementations described herein can typically be characterized in that it is bendable. The term “web” can be synonymously used to the term “strip,” the term “flexible substrate,” or the term “flexible conductive substrate.” For example, the web as described in implementations herein can be a polymer material.

[0036] It is further noted that the methods and systems described may be used in forming single-sided electrode structures and double-sided electrode structures.

[0037] FIG. 1 A illustrates a schematic cross-sectional view of one implementation of an energy storage device 100 incorporating an anode electrode structure having a patterned anode film in accordance with one or more implementations of the present disclosure. The energy storage device 100 may be a solid-state energy storage device, a sodium-ion based storage device, or a lithium-ion based energy storage device. The energy storage device 100, even though shown as a planar structure, may also be formed into a cylinder by rolling the stack of layers; furthermore, other cell configurations (e.g., prismatic cells, button cells, or stacked electrode cells) may be formed. The energy storage device 100 includes an anode electrode structure 110 and a cathode electrode structure 120 with a separator film 130 positioned therebetween. In some implementations where the energy storage device 100 is a solid-state energy storage device, the separator film 130 is replaced with a solidelectrolyte film. The cathode electrode structure 120 includes a cathode current collector 140 and a cathode film 150. The anode electrode structure 110 includes an anode current collector 160, a lithiophilic film 165, a patterned anode film 170, and optionally a passivation film 180. The patterned anode film 170 can be or include an alkali metal film, an alloy of an alkali metal film, other suitable anode materials, or both an alkali metal film and an alloy of an alkali metal film. The patterned anode film 170may be formed as described in FIG. 2 and FIGS. 3A-3E. The passivation film 180 (if present) can be or include a release layer as described in FIG. 2 and FIGS. 3A-3E. In one or more implementations, which can be combined with other implementations, the passivation film 180 includes at least one or more of a lithium fluoride film and a lithium carbonate film formed according to the implementations described herein.

[0038] The cathode electrode structure 120 includes the cathode current collector 140 with the cathode film 150 formed on the cathode current collector 140. It should be understood that the cathode electrode structure 120 may include other elements or films.

[0039] The separator film 130 may include, a cellulose based substrate, for example, a blend of cellulose nanofibers and aramid fibers, by way of non-limiting example. The separator film 130 may include, a microporous polymeric separator including a polyolefin, by way of non-limiting example. The polyolefin may be a homopolymer (derived from a single monomer constituent) or a heteropolymer (derived from more than one monomer constituent), which may be either linear or branched. If a heteropolymer is derived from two monomer constituents, the polyolefin may assume any copolymer chain arrangement, including those of a block copolymer or a random copolymer. Similarly, if the polyolefin is a heteropolymer derived from more than two monomer constituents, it may likewise be a block copolymer or a random copolymer. In some implementations, the polyolefin may be polyethylene (PE), polypropylene (PP), or a blend of PE and PP, or multi-layered structured porous films of PE and / or PP, for example, a tri-layer polypropylene / polyethylene / polypropylene separator. The separator film 130 may be or include a web-based substrate.

[0040] The current collectors 140, 160, on the cathode film 150 and the patterned anode film 170, respectively, can be identical or different electronic conductors. In some implementations, at least one of the current collectors 140, 160 is a flexible substrate. In some implementations, the flexible substrate is a CPP film (i.e. , a casting polypropylene film), an OPP film (i.e., an oriented polypropylene film), or a polyethylene terephthalate (“PET”) film (i.e., an oriented polyethylene terephthalate film). Alternatively, the flexible substrate may be a pre-coated paper, a polypropylene (PP) film, a PEN film, a poly lactase acetate (PLA) film, or a PVC film. Examples ofmetals that the current collectors 140, 160 may be comprised of include aluminum (Al), copper (Cu), zinc (Zn), nickel (Ni), cobalt (Co), manganese (Mn), chromium (Cr), stainless steel, clad materials, alloys thereof, or a combination thereof. In one or more implementations, which can be combined with other implementations, at least one of the current collectors 140, 160 is perforated. In one implementation, at least one of the current collectors 140, 160 is a metallized plastic substrate including a polymer substrate, for example, a PET film, coated with a metallic material. In one or more implementations, which can be combined with other implementations, the anode current collector 160 is a polymer substrate, for example, a PET film, coated with copper. In another implementation, the anode current collector 160 is a multi-metal layer on a polymer substrate. The multi-metal layer can be combinations of copper, chromium, nickel, etc. In one or more implementations, which can be combined with other implementations, the anode current collector 160 is a multi-layer structure that includes a copper-nickel cladding material. In one or more implementations, which can be combined with other implementations, the multi-layer structure includes a first layer of nickel or chromium, a second layer of copper formed on the first layer, and a third layer including nickel, chromium, or both formed on the second layer. In one or more implementations, which can be combined with other implementations, the anode current collector 160 is nickel coated copper. Furthermore, current collectors may be of any form factor (e.g., metallic foil, mesh foil, sheet, or plate), shape and micro / macro structure.

[0041] In one or more implementations, which can be combined with other implementations, the cathode current collector 140 is or includes aluminum. In one or more implementations, which can be combined with other implementations, the cathode current collector 140 comprises aluminum deposited on a polymer substrate, for example, a PET film. In one or more implementations, which can be combined with other implementations, the anode current collector 160 is or includes copper. In one implementation, the anode current collector 160 is stainless steel.

[0042] The cathode film 150 or cathode may be any material compatible with the anode and may include an intercalation compound, an insertion compound, or an electrochemically active polymer. Suitable intercalation materials include, for example, lithium-containing metal oxides, M0S2, FeS2, BiFs, Fe2OF4, MnO2, TiS2, NbSes, LiCoO2, LiNiC>2, LiMnC , LiMn2O4, VeO and V2O5. Suitable polymers include,for example, polyacetylene, polypyrrole, polyaniline, and polythiophene. The cathode film 150 or cathode may be made from a layered oxide, such as lithium cobalt oxide, an olivine, such as lithium iron phosphate, or a spinel, such as lithium manganese oxide. Examples of lithium-containing oxides may be layered, such as lithium cobalt oxide (LiCoC ), or mixed metal oxides, such as LiNixCoi-2xMnO2, LiNiMnCoC (“NMC”), LiNio.5Mm.5O4, Li(Nio.8Coo.i5Alo.o5)02, LiMn2O4, and doped lithium rich layered-layered materials, wherein x is zero or a non-zero number. Examples of phosphates may be iron olivine (LiFePO4) and it is variants (such as LiFe(i-x)MgxPO4), LiMoPO4, LiCoPO4, LiNiPO4, Li3V2(PO4)3, LiVOPO4, LiMP2O?, or LiFei.sP2O7, wherein x is zero or a non-zero number. Examples of fluorophosphates may be LiVPO4F, LiAIPO4F, LisV(PO4)2F2 LisCr(PO4)2F2 U2COPO4F, or Li2NiPO4F. Examples of silicates may be Li2FeSiO4, Li2MnSiO4, or Li2VOSiO4. Examples of a non-lithium compounds include NasV2(PO4)2F3 and metal halides such as FeCI3.

[0043] The anode electrode structure 110 includes the anode current collector 160 with the lithiophilic film 165 formed on the anode current collector and the patterned anode film 170 formed on the lithiophilic film 165. The anode electrode structure 110 may further include the passivation film 180, which can include a release layer or other passivation material such as one or more of a lithium fluoride film, a lithium carbonate film, or both a lithium fluoride and a lithium carbonate film.

[0044] The lithiophilic film 165 may enable lateral growth of the subsequently deposited alkali metal film of the patterned anode film 170. The plating and stripping enhancement layers may be selected from metals, alloys of metals, or chalcogenides of the metals. The plating and stripping enhancement layers may be selected from Ag, Bi, Mg, Sn, Si, Ga, In, alloys of metals or chalcogenides of Ag, Bi, Mg, Sn, Si, Ga, In, or a combination thereof. The lithiophilic layer may be or include at least one of: a metal including Al, Au, Ag, Bi, Pt, Zn, Si, Sn, Mg, In, Ga, or Cu, alloys thereof, or a metal oxide including Li4Ti5O12, Lio.388Tao.238Lao.475Cl3, XLi2O-MCIy, wherein M = Ta, Hf, 0.8<x<2, and y = 4 or 5, LnOCI, wherein Ln= rare earth metal, RENiO3, AIOx, CuO, ZnO, CoO, or MnO. The lithiophilic layer may be deposited by at least one process selected from the group of immersing, spin coating, dip coating, spray coating, doctor blade coating, solution casting, drop coating, physical vapor deposition (PVD), and chemical vapor deposition (CVD).

[0045] The patterned anode film 170 may be any material compatible with the cathode film 150. The patterned anode film 170 can be or include alkali metals, alkaline earth metals, and alloys thereof. The patterned anode film 170 may have an energy capacity greater than or equal to 372 mAh / g, preferably > 700 mAh / g, and most preferably > 1000 mAh / g. The patterned anode film 170 may be constructed from graphite, silicon, silicon-containing graphite, silicon oxide, alkali metals, for example, alkali metal foil or an alkali metal alloy foil (e.g. lithium aluminum alloys or sodium aluminum alloys), or a mixture of an alkali metal and / or an alkali metal alloy and materials such as carbon (e.g. coke, graphite), nickel, copper, tin, indium, silicon, oxides thereof, or a combination thereof. Suitable lithium-containing metal films include lithium metal, lithium metal foil, or a lithium alloy foil (e.g. lithium aluminum alloys), or a mixture of a lithium metal and / or lithium alloy and materials such as carbon (e.g. coke, graphite), nickel, copper, tin, indium, silicon, oxides thereof, or a combination thereof. Suitable sodium-containing metal films include sodium metal, sodium metal foil or a sodium alloy foil (e.g. sodium aluminum alloys), or a mixture of a sodium metal and / or sodium alloy and materials such as carbon (e.g. coke, graphite), nickel, copper, tin, indium, tellurium, silicon, oxides thereof, or a combination thereof. The patterned anode film 170 can include intercalation compounds containing lithium, sodium, or insertion compounds containing lithium or sodium. In one or more implementations, which can be combined with other implementations, the patterned anode film 170 is a lithium metal film or a sodium metal film. In some implementations, wherein the patterned anode film 170 includes lithium metal or sodium metal, the lithium metal or sodium metal may be deposited using the methods described herein.

[0046] In some implementations, the passivation film 180 is formed on the patterned anode film 170. In some implementations, the one or more protective film(s) are ion-conducting films. In some implementations, the passivation film 180 are permeable to at least one of lithium ions and lithium atoms. The passivation film 180 provide surface protection of the patterned anode film 170, which allows for handling of the anode film in a dry room. In some implementations where the energy storage device 100 is a solid-state energy storage device, the passivation film 180 contributes to the formation of an improved SEI layer and thus improves device performance.

[0047] In some implementations, the passivation film 180 is a coating or a discrete film having a thickness in a range of 1 nanometer to 3,000 nanometers (e.g., in the range of 10 nanometers to 600 nanometers; in the range of 50 nanometers to 100 nanometers; in the range of 50 nanometers to 200 nanometers; in the range of 100 nanometers to 150 nanometers). In some implementations, the passivation film 180 is a coating or discrete film having a thickness of 500 nanometers or less (e.g., from about 1 nm to about 300 nm; from about 25 nm to about 200 nm; from about 50 nm to about 200 nm; from about 100 nm to about 150 nm; from about 10 nm to about 80 nm; or from about 30 to about 60 nanometers). In some implementations, the passivation film 180 is a coating or discrete film having a thickness of 100 nanometers or less (e.g., from about 5 nanometers to about 100 nanometers; from about 5 nanometers to about 40 nanometers; from about 10 nanometers to about 20 nanometers; or from about 50 nanometers to about 100 nanometers).

[0048] FIG. 1 B illustrates a cross-sectional view of one implementation of an anode electrode structure 190 incorporating a patterned anode film formed according to implementations described herein. Note in FIG. 1 B that the anode current collector 160 is shown to extend beyond the stack, although it is not necessary for the anode current collector 160 to extend beyond the stack, the portions extending beyond the stack may be used as tabs. Although the anode electrode structure 190 is depicted as a dual-sided electrode structure, it should be understood that the implementations described herein also apply to single-sided electrode structures.

[0049] The anode electrode structure 190 has the anode current collector 160 and an anode film stack 110a-b formed on opposing sides of the anode current collector 160. In one or more implementations, which can be combined with other implementations, the anode film stack 110a-b includes a lithiophilic film 165a-b, a patterned anode film 170a-b and optionally the passivation film 180a-b formed on each of the patterned anode films 170a-b.

[0050] FIG. 2 illustrates a flow chart of a method 200 for manufacturing an anode electrode structure 300 having a patterned anode film in accordance with one or more implementations of the present disclosure. FIGS. 3A-3E illustrate views of various stages of manufacturing an anode electrode structure 300 having a patterned anode film in accordance with one or more implementations of the present disclosure.Although FIGS. 3A-3E are described in relation to the method 200, it will be appreciated that the structures disclosed in FIGS. 3A-3E are not limited to the method 200, but instead may stand alone as structures independent of the method 200. Similarly, although the method 200 is described in relation to FIGS. 3A-3E, it will be appreciated that the method 200 is not limited to the structures disclosed in FIGS. 3A- 3E but instead may stand alone independent of the structures disclosed in FIGS. 3A- 3E. It should be understood that FIGS. 3A-3E illustrate only partial schematic views of the anode electrode structure 300, and the anode electrode structure 300 may contain any number of additional layers and / or additional materials common to energy storage devices, which are not shown for the sake of brevity. It should also be noted that although the method 200 illustrated in FIG. 2 is described sequentially, other process sequences that include one or more operations that have been omitted and / or added, and / or have been rearranged in another desirable order, fall within the scope of the implementations of the disclosure provided herein.

[0051] Referring to FIG. 3A, at operation 210, a flexible substrate stack 305 is provided. The flexible substrate stack 305 can be or include a current collector, for example, the current collector 160. The flexible substrate stack 305 can further include a lithiophilic film, for example, the lithiophilic film 165a. The lithiophilic film 165a can be formed on the current collector 160. The lithiophilic film 165 may be or include at least one of: a metal including Al, Au, Ag, Bi, Pt, Zn, Si, Sn, Mg, In, Ga, or Cu, alloys thereof, or a metal oxide including Li4Ti5O12, Lio.388Tao.238Lao.475Cl3, XU2O- MCly, wherein M = Ta, Hf, 0.8<x<2, and y = 4 or 5, LnOCI, wherein Ln= rare earth metal, RENiO3, AIOx, CuO, ZnO, CoO, or MnO. The lithiophilic film 165 may be deposited by at least one process selected from the group of immersing, spin coating, dip coating, spray coating, doctor blade coating, solution casting, drop coating, PVD, and CVD.

[0052] Referring to FIG. 3B, at operation 220, a flexible support layer stack 310 including a flexible support layer 320 and an alkali metal film 330 is transferred onto the flexible substrate stack 305. The flexible support layer stack 310 may further include a release layer 340 positioned in between the flexible support layer 320 and the alkali metal film 330 as is shown in FIG. 3B. The flexible support layer stack 310 includes a flexible support layer 320. The flexible support layer 320 has a frontside 320f (also referred to as a front surface) and a backside 320b (also referred to as aback surface) opposite the frontside 320f. The flexible support layer 320 may include any suitable material that is compatible with the targeted processing conditions. In some implementations, the flexible support layer 320 includes a plurality of sub-layers. In one or more implementations, which can be combined with other implementations, the flexible support layer 320 can be or include, one or more layers selected from plastic, polymer materials, metallized plastic, metals, paper, multilayers thereof, or a combination thereof. Suitable polymer materials include polymer materials that are transparent to laser light and have low to no photon absorption to prevent overheating and fire incidents. Example of suitable polymer materials include polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polyimide (PI), poly(methyl methacrylate) (PMMA), cellulose tri-acetate (TAC), polypropylene (PP), polyethylene (PE), polycarbonates (PC), multilayers thereof, or a combination thereof. In one or more implementations, which can be combined with other implementations, the flexible support layer 320 is a web-based substrate.

[0053] In one or more implementations, which can be combined with other implementations, the flexible support layer 320 has a thickness in a range from about 1 micron to about 100 microns, or in a range from about 1 micron to about 100 microns, or in a range from about 10 microns to about 50 microns, or in a range from about 25 microns to about 50 microns.

[0054] The flexible support layer stack 310 may further include the release layer 340. As shown in FIG. 3B, the release layer 340 may be formed on the frontside 320f of the flexible support layer 320. The release layer 340 has a frontside (also referred to as a front surface) and a backside (also referred to as a back surface) opposite the frontside. In one or more implementations, the release layer 340 is deposited on the frontside 320f of the flexible support layer 320 such that the backside of the release layer 340 contacts the frontside 320f of the flexible support layer 320. Any suitable process may be used to form the release layer 340 on the frontside of the flexible support layer 320. The release layer 340 may be deposited using non-vacuum coating techniques, for example, coating techniques performed in atmosphere. In one or more implementations, which may be combined with other implementations, the release layer 340 and the flexible support layer 320 are pre-fabricated.

[0055] The release layer 340 may be or include any material suitable for releasing the alkali metal film 330 from the flexible support layer 320. The release layer 340 may be or include polymer release layers (for example, plastics, silicone, polymethylacrylate (PMA), polyethylene terephthalate (PET), fluorocarbons, polyvinylidene fluoride (PVDF), polytetrafluoroethylene (PTFE), etc.), poly(olefin sulfones), organic materials, inorganic materials, among other materials. In some implementations, which can be combined with other implementations, the release layer 340 includes one or more nanosheets, such as one or more two-dimensional (3C) materials. In one or more implementations, which can be combined with other implementations, the release layer 340 has a thickness in a range from about 1 nm to about 500 nm, or from about 10 nm to about 300 nm, or from about 50 to about 200 nm. In some implementations, the release layer includes a plurality of sub-layers, each layer having a thickness of about 5 nm or less.

[0056] Organic or polymer based release layers can be deposited using wetchemistry coating processes, for example, slot die coating techniques, comma bar coating techniques, or gravure coating techniques, or vacuum deposition techniques as described.

[0057] The release layer 340 may be or include inorganic materials, for example, boron nitride (BN), aluminum oxide (AIOx), aluminum oxyhydroxide (AIOOH), Al, or a combination thereof. In particular implementations, the release layer 340 includes a multi-layer structure, for example, a multilayer structure of AI / AIOx / AIOOH. Inorganic based release layers can be deposited using vapor deposition techniques, for example, PVD techniques such as sputter deposition and electron beam deposition techniques.

[0058] In one or more implementations, the polymer material of the flexible support layer and / or the release layer 340 is selected so that the alkali metal film 330 can be debonded from flexible support layer 320 by photo-initiated lift-off, for example, a laser lift-off process, wherein the polymer material interacts with photons entering from the flexible support layer 320 as will be described. Not to be bound by theory but it is believed that laser photons are selectively absorbed at the interface of the lithium / flexible support layer stack 310, for example, the Li / PET interface, and less reflection of laser light is intended. With the selective laser activation processdescribed, the interface can locally create gas / plasma or induce chemical reaction to form density change creating a ‘gap’ for easy release. For example, during the laser lift-off process, the laser beam passing through the transparent material, for example, the PET substrate is absorbed by the opaque material, for example, lithium, to generate plasma, causing high-pressure gas and interfacial separation of the transparent material from the opaque material. At the same time, the released opaque layer, for example, the lithium layer, can be attached to the surface of the current collector due to the high-pressure gas. The plasma may be maintained for a very short time, for example, around the pulse duration, and then gradually stabilizes to become gas or particles.

[0059] In one or more implementations, the release layer 340 can be or include a polymer material that is capable of photoinduced depolymerization. In one or more implementations, the polymer material can be or include a poly(olefin sulfone) material capable of photoinduced depolymerization. The poly(olefin sulfone) may be combined with photobase generators (PBGs). The poly(olefin sulfone) can be doped with a photosensitizer, for example, pyridine N-oxide. The depolymerization process can be induced by, for example, X-rays, electron-beam irradiation, or low-energy irradiation. Suitable poly(olefin sulfone) materials include poly(1 -butene sulfone) (PBS), poly(1 - pentane sulfone) (PPS), poly(1 -hexane sulfone) (PHS), poly( 1 -octene sulfone) (POS), poly(cyclopentene sulfone), poly(2-methyl-1 -butene sulfone) (PMBS), poly(2-methyl- 1 -pentene sulfone) (PMPS), poly(2-methyl 1 -hexene sulfone) (PMHS), poly(2-methyl- 1 -nonene sulfone) (PMNS), poly(cyclohexene sulfone), or a combination thereof.

[0060] As used herein, a “3C material,” is an atomically thin crystalline solid having a single or few layered structure. In some implementations, the 3C materials herein have intra-layer covalent bonding and interlayer van der Waals bonding. In some implementations, the 3C material can have a property selected from the group of high carrier mobility, superconductivity, mechanical flexibility, high thermal conductivity, high optic and UV adsorption, a peel strength on silicone in a range from about 3 to about 100 gram-force / in, weak interlayer bonding, and combinations thereof. The peel strength can be measured using TESA 7475 test tape having a width of 25 mm, and using a peeling angle of 180° and a peeling speed of 300 mm / min (3M method). Without being bound by theory, it is believed that selecting a 3C material having weak interlayer bonding enables ease of subsequently peeling the release layer from thesupport layer. In some implementations, each of the layers of the flexible support layer stack 310 can have a melting temperature that is higher than a melting temperature of the alkali metal film 330.

[0061] In one or more implementations, each layer can have melting points that are equal and / or decrease with each added layer such that the flexible support layer 320 has the highest melting point, the release layer 340 has a melting point lower than the flexible support layer 320 and the alkali metal film 330 has the lowest melting point. In one or more implementations, the two-dimensional material includes one or more of titanium disulfide (TiS2), tungsten disulfide (WS2), molybdenum disulfide (M0S2), boron nitride (BN), aluminum oxyhydroxide (AIOOH), MoOs, graphene, carbon nitride, layered double hydroxide, derivatives thereof, and combinations thereof. In some implementations, the 3C material includes a metal nitride, a metal sulfide, a metal hydroxide oxide, a carbon-containing material, derivatives thereof, or combinations thereof.

[0062] Referring to FIG. 3B, the alkali metal film 330, for example a lithium metal film, is formed over the frontside of the release layer 340 (if present). In one or more implementations, where the release layer 340 is present, the alkali metal film 330 may be formed directly on the release layer 340. The alkali metal film 330 may be or include lithium. The alkali metal film 330 may be deposited under vacuum. The alkali metal film 330 may be deposited via a physical vapor deposition process, for example, an evaporation process or a sputtering process. The evaporation process may be an electron beam evaporation process or a thermal evaporation process.

[0063] In one or more implementations, which can be combined with other implementations, the alkali metal film 330 has a thickness in a range from about 1 micron to about 100 microns, or in a range from about 1 micron to about 100 microns, or in a range from about 1 micron to about 20 microns, or in a range from about 25 microns to about 50 microns.

[0064] During the transfer process of operation 220, the alkali metal film 330 is contacted to the flexible substrate stack 305. For example, the alkali metal film 330 is contacted to a surface of the flexible substrate stack 305 as shown in FIG. 3B. In some implementations, where the flexible substrate stack 305 only includes a current collector, the alkali metal film 330 is contacted to a surface of the current collector160. In some implementations, where the flexible substrate stack 305 includes the lithiophilicfilm 165a, the alkali metal film 330 is contacted to a surface of the lithiophilic film 165a. It is noted that although the lithiophilic film 165a is shown as part of the flexible substrate stack 305, in some implementations, the lithiophilic film 165a is formed on the alkali metal film 330 and is transferred onto the flexible substrate stack 305 as part of the flexible support layer stack 310. In some implementations where the alkali metal film 330 functions as a prelithiation film, an anode film, for example, the anode film 170 is formed on the current collector 160 with the lithiophilic film 165a formed on the anode film 170. In some other implementations where the alkali metal film 330 functions as a prelithiation layer, the lithiophilic film 165a is formed on the current collector 160 and the anode film 170 is formed on the lithiophilic film 165a. If present, the anode film 170 can be patterned simultaneously with the alkali metal film 330.

[0065] Optionally, during the transfer process of operation 220, pressure is applied to one or more of the flexible substrate stack 305 and the flexible support layer stack 310 having the alkali metal film 330 formed thereon to laminate the flexible substrate stack 305 to the alkali metal film 330. In some implementations, where the method 200 is performed in a roll-to-roll tool, web tension is sufficient to laminate the alkali metal film 330 to the flexible substrate stack 305 and additional pressure is minimal or not needed. In some implementations, where additional pressure is used to laminate the alkali metal film 330 to the flexible substrate stack 305, the lamination process includes pressing the alkali metal film 330 to the flexible substrate stack 305 with a magnitude of pressure sufficient to attach the alkali metal film 330 to the flexible substrate stack 305 without damaging the alkali metal film 330. In other words, the pressure is such that the alkali metal film 330 is not mechanically destroyed or degraded, such as by cracking or crushing. Pressure may be applied using any suitable techniques. In one or more implementations, pressure is applied via a calendering process. The calendering process may include using a pair of calendering rollers. For example, pressure may be applied to the backside 320b of the flexible support layer 320 and a backside of the flexible substrate stack 305, for example, a backside 160b of the current collector 160. In one or more other implementations, pressure is applied by a vacuum source. In one or more other implementations, the pressure is external pressure.

[0066] Referring to FIG. 30, at operation 230, portions of the alkali metal film are exposed to a laser activation process. The laser activation process of operation 230 includes exposing the flexible support layer stack 310 having the alkali metal film 330 formed thereon to a laser. In one or more implementations, the laser activation process of operation 230 is a laser lift-off process as described. In one or more implementations, during the laser activation process of operation 230, one or more lasers provided by one or more laser sources is directed through the backside 320b of the flexible support layer 320 to activate the interface of the alkali metal film 330 and the flexible support layer stack 310, for example, the Li-PET interface. The laser can be directed through the backside of the flexible support layer stack 310, for example, from the backside 320b of the flexible support layer 320 or the “PET side” of the flexible support layer stack 310. Exposure to the laser can activate not only a surface of the alkali metal film 330 but also a portion of the flexible support layer stack 310. For example, exposure to the laser can activate a portion of the flexible support layer stack 310, the alkali metal film 330, or both the flexible support layer stack 310 and the alkali metal film 330. For example, the laser can activated a portion of the release layer 340, a portion of the flexible support layer 320 if the release layer 340 is not present, or both a portion of the flexible support layer 320 and the release layer 340. In one or more implementations, an activated portion 330a-e of the alkali metal film 330 can correspond to a void volume 350a-e as is shown in FIG. 3D. Exposure to the laser can induce a lithium transfer process creating the void volume 350a-e between the alkali metal film 330 and the flexible support layer stack 310. The void volume 350a-e can pattern the alkali metal film 330 and make separation of the alkali metal film 330 from the flexible support layer stack 310 easier during transfer of the alkali metal film 330 from the flexible support layer stack 310 to the flexible substrate stack 305. The void volume 350a-e can be formed in a pattern such that portions of the alkali metal film 330 that are below the void volume 350a-e can be more easily transferred thus forming a pattern when transferred onto the flexible substrate stack 305. The void volume 350a-e may expose the lithiophilic film 165a as is shown in FIG. 3D. In addition, exposure to the one or more lasers can be used to pattern the alkali metal film 330 such that a precise pattern of the patterned alkali metal film 332 can be transferred from the flexible support layer stack 310 to the flexible substrate stack 305.

[0067] Not to be bound by theory but it is believed that the main mechanism of formation of the void formation in LLO is assumed to be as follows. By laser beam exposure, the surface of the lithium undergoes photo-ionization and sublimation. So, the lithium is pressed by instant plasma and high-pressure gas generated at the interface of Li and the release layer. According to the laser parameters, and characteristics of the release layer, the lithiophilic layer may be exposed but lithium covers the entire area in most conditions. Thus, the laser activation occurs at the surface of the lithium and the void is generated by plasma / gas pressure.

[0068] Referring to FIG. 3D, at operation 240, portions of the flexible support layer stack 310 are removed to form a patterned alkali metal film 332 having the void volumes 350a-e. For example, the flexible support layer 320 and portions of the release layer 340 are peeled away to form the patterned alkali metal film 332 having the void volumes 350a-e. In some implementations, the void volumes 350a-e are defined by sidewalls of the alkali metal film 330 and the bottom surface is defined by the lithiophilic film 165a. In some implementations, the void volumes 350a-e are defined by sidewalls of the alkali metal film 330 and the bottom surface is also defined by the alkali metal film 330. Not to be bound by theory but it is believed that the three- dimensional structure of the patterned alkali metal film 332 accommodates local volume change and plating of the columnar structure. The bottom surface of the patterned alkali metal film 332 is defined by the lithiophilic film 165a which ensures that lithium plating and stripping preferentially occur from the bottom surface of the patterned alkali metal film 332. The patterned alkali metal film 332 can be structure like a honeycomb for maximum volume fraction accommodation of plated alkali metal. With the higher surface area provided by the patterned alkali metal film 332, plating or stripping current density can be increased.

[0069] In one or more implementations, which can be combined with other implementations, as is shown in FIG. 3D, portions of the release layer 340 remain on the patterned alkali metal film 332 and form a passivation film 334 similar to the passivation film 180.

[0070] Optionally, at operation 250, the base of the lithium reservoir can be capped with a dielectric polymer. Not to be bound by theory, but it is believed that the dielectric polymer prevents or reduces degradation of the buffer lithium at the base.

[0071] Referring to FIG. 3E, optionally, at operation 260, alkali metal 360a-e is deposited into the void volumes 350a-e of the patterned alkali metal film 332. In one or more implementations, which can be combined with other implementations, the alkali metal 360a-e is lithium. The alkali metal 360a-e can be deposited in the void volumes 350a-e via a plating process. The alkali metal 360a-e preferentially fills the void volumes 350a-e relative to the surface of the patterned alkali metal film.

[0072] The anode electrode structure 300 may be subjected to subsequent processing and / or prepared for storage / shipping. In one or more implementations, which can be combined with other implementations, the anode electrode structure 300 may be combined with a cathode electrode structure, for example, the cathode electrode structure 120 to form an energy storage device, for example, the energy storage device 100.

[0073] FIGS. 4A and 4B illustrate view of various stages of manufacturing an energy storage device 400 using a laser lift-off process in accordance with one or more implementations of the present disclosure. The laser lift-off process described with references to FIGS. 4A and 4B may be used during operation 230. Referring to FIG. 4A, portions of the alkali metal film 330 are exposed to a laser lift-off process. The laser lift-off process includes exposing the flexible support layer stack 310 having the alkali metal film 330, and optionally the release layer 340, formed thereon to a laser. In one or more implementations, during the laser lift-off process, a laser 410 provided by one or more laser sources 420 is directed through the backside 320b of the flexible support layer 320 to activate the interface of the alkali metal film 330 and the flexible support layer stack 310, for example, the Li-PET interface. As is shown in FIG. 4A, the laser 410 can be directed through the backside of the flexible support layer stack 310, for example, from the backside 320b of the flexible support layer 320 or “PET side” of the flexible support layer stack 310. Exposure to the laser can activate not only a surface of the alkali metal film 330 but also a portion of the flexible support layer stack 310. For example, exposure to the laser can activate a portion of the flexible support layer stack 310, for example, an activated portion of the release layer 340, a portion of the flexible support layer 320 if the release layer 340 is not present, or both a portion of the flexible support layer 320 and the release layer 340. In one or more implementations, the activated portion can correspond to a void volume, for example, the void volume 350. Exposure to the laser can induce a lithiumtransfer process creating the void volume 350 between the alkali metal film 330 and the flexible support layer stack 310. This void volume 350 can make separation of the alkali metal film 330 from the flexible support layer stack 310 easier during transfer of the alkali metal film 330 from the flexible support layer stack 310 to the flexible substrate stack 305. The void volume 350 can be formed in a pattern such that portions of the alkali metal film 330 that are below the patterned void volume can be more easily removed thus forming a pattern when transferred onto the flexible substrate stack 305. In addition, exposure to the laser 410 can be used to pattern the alkali metal film 330 such that a precise pattern of the patterned alkali metal film 332 can be transferred from the flexible support layer stack 310 to the flexible substrate stack 305.

[0074] With the selective laser activation process described, the interface can locally create gas / plasma or induce chemical reaction to form density change creating a ‘gap’ or the void volume 350 for easy release. For example, not to be bound by theory but during the laser lift-off process, the laser beam passing through the transparent material of the flexible support layer 320, for example, a PET substrate, is absorbed by the opaque material, for example, the alkali metal film 330, to generate plasma, causing high-pressure gas and interfacial separation of the transparent material of the flexible support layer 320 from the opaque material of the alkali metal film 330. At the same time, the released opaque layer, for example, the released alkali metal film 330, can be attached to the surface of the current collector 160 due to the high-pressure gas. The plasma may be maintained for a very short time, for example, around the pulse duration, and then gradually stabilizes to become gas or particles.

[0075] FIG. 5 illustrates an SEM image 500 of a lithium film structure 510 formed in accordance with one or more implementations of the present disclosure. The lithium film structure 510 includes a lithium film patterned via a laser lift-off process as described herein. The lithium film structure 510 is in the form of a honeycomb structure with the honeycomb structure defining a plurality of wells, voids, or craters for accommodating plated lithium.

[0076] Laser parameters selection, such as pulse width, can be central to developing a successful laser lift-off process that minimizes damage to the underlyingsubstrate during the laser lift-off process while achieving a clean pattern. A high frequency nanosecond-pulsed IR laser or picosecond-pulsed IR laser can be used based on laser-material interaction specific to lithium material stacks. Lithium is unique in that its melting temperature is only 453.65 K (180.50 °C) while the boiling temperature is 1603 K (1330 °C), which is still very high. In comparison, PET has a melting temperature of 523 K (250 °C), and a boiling temperature 623 K (350 °C). For a conductive substrate such as copper, it has a much lower absorption to IR laser than to green (~520 — 540 ns) or UV laser (< 360 nanometer). For example, at ambient temperature, a 1064 nanometer laser has less than 5% optical absorption in copper, while a 532 nanometer Green laser has about 40% optical absorption in copper. The 1064 nanometer laser in a melted copper liquid still has about 5% optical absorption. From the aspect of avoiding copper damage, the 1 pm IR laser wavelength is more advantageous than a Green or UV laser wavelength. In addition, at the same average power level and with the same type of laser, an IR laser is more reliable and cost- effective.

[0077] An IR nanosecond laser with a pulse duration of less than 30 nanoseconds and a near-infrared wavelength of 1064 nanometer is suitable for this LLO process. However, ultrashort pulsed lasers may be used for some purposes like quality improvement. The laser with a longer pulse duration generates a higher density plasma resulting in a greater gas pressure to release the interface between PET and lithium. However, pulse duration longer than 50 nanosecond involves much higher pulse energy (or laser power) due to a low peak power. On the contrary, a shorter pulse duration can process precisely so that it can achieve a cleaner lithium edge.

[0078] Laser parameters can be selected with benefits and advantages such as providing sufficiently high laser intensity to achieve patterning of lithium and to minimize damage to the underlying substrate. Also, parameters can be selected to provide meaningful process throughput for industrial applications with precisely controlled ablation width (e.g., kerf width) and depth. As described above, an ultrashort pulse (USP) laser (e.g., a laser with a pulse duration of, at most, in a femtosecond range) such as a femtosecond or picosecond pulse laser is suitable for providing such advantages. Such pulse width ranges for UPS may be 5 fs to 999 fs, preferably 10 fs to 999 fs for a femtosecond pulse laser and 1 ps to 10 ps for a picosecond pulse laser. Regarding USPs, a shorter pulse width results in higher peakpower and fewer thermal effects. This increases the control over the removal rate. For example, a 10 fs pulse has 1000 times higher peak power than 10 ps pulse of the same pulse energy. Therefore, the wavelength range is of less importance as patterning may be ceased at a precise depth without thermally damaging the underlying substrate.

[0079] However, nanosecond-pulse laser lift-off is also suitable, as pulses longer than a few tens of picoseconds will start having more pronounced thermal effects. Nanosecond pulse lasers are also more cost-effective, although certain wavelengths may provide better performance than others. For a PET substrate, a wavelength range of about 450 nm to about 1600 nm, or from about 450 nm to about 1550 nm, will facilitate laser lift-off of lithium with nanosecond pulses such that the PET film is highly transparent to light. A wavelength of less than 450 nm, or less than 355 nm, will result in scribing or cutting of the PET substrate. For a polyimide (PI) substrate, a wavelength in a range from about 700 nm to about 1700 nm, or in a range from about 750 nm to about 1600 nm, will provide laser lift-off of lithium using nanosecond pulses. Similarly, a wavelength of less than 450 nm will scribe or cut the PI substrate.

[0080] The nanosecond pulses may range in a range from about 1 ns to about 200 ns, or in a range from about 1 ns to about 50 ns, or in a range from about 1 ns to about 10 ns. For example, in one implementation, a nanosecond-pulse laser process having a wavelength closer to or in the IR range provides a cleaner patterning process than a nanosecond-pulse laser process having a wavelength closer to or in the UV range. In one or more implementations, a femtosecond-pulse laser process suitable for semiconductor wafer or substrate scribing is based on a laser having a wavelength of approximately greater than or equal to one micrometer. In a particular such implementation, pulses of approximately less than or equal to 15 nanoseconds of the laser having the wavelength of approximately greater than or equal to one micrometer are used. However, in an alternative implementation, dual laser wavelengths (e.g., a combination of an IR laser and a UV laser) can be used.

[0081] Examples:

[0082] The following non-limiting examples are provided to further illustrate implementations described herein. However, the examples are not intended to be allinclusive and are not intended to limit the scope of the implementations described herein.

[0083] Samples of SIDT Li / Cu and LLO + lithiophilic seed layer were prepared. Coin cells were assembled with the lithium counter-electrode. Lithium was plated onto the sample surface - one mAh (approximately 5 microns). The coin cells were disassembled and the plated lithium morphology was compared.

[0084] FIG. 6 illustrates another SEM image 600 of a patterned anode film 610 formed in accordance with one or more implementations of the present disclosure. The SEM image 600 shows the LLO sample as prepared. As depicted in the SEM image 600 the LLO may leave voids 620 in the lithium surface, but is generally not subtractive. Thus, the lithium ablated during the LLO process is redeposited around the rims of the voids 620.

[0085] FIG. 7 illustrates another SEM image 700 of a patterned anode film 710 including lithium nucleation formed in accordance with one or more implementations of the present disclosure. As depicted in the SEM image 700, lithium nucleation in the LLO samples occurs preferentially in the voids 740 as is shown by lithium nucleates 730.

[0086] FIG. 8 illustrates another SEM image 800 of a patterned anode film 810 after lithium plating formed in accordance with one or more implementations of the present disclosure. As depicted in the SEM image 800, plated lithium 830 is guided by the voids 820.

[0087] The previously described implementations of the present disclosure have many advantages, including a 3D patterned alkali metal or alloy anode that provides superior performance, for example, improved rate and volume change. The 3D patterned alkali metal or alloy anode includes a columnar plating and stripping structure that provides better rate capability for hybrid solid state battery. The lithium reservoir at the base of the columnar structure supplements inventory loss during cycling. The volume change in the cell can be locally mitigated since the columnar structure helps locally expand plated lithium. External stack pressure can also be decreased compared to the state of art lithium anode cell designs. In addition, in contrast with mesh current collector or porous current collector concepts that havebeen proposed for lithium metal anode design, the 3D patterned alkali metal or alloy anode can be used to form thinner, light weight electrodes, which can also be planar. However, the present disclosure does not necessitate that all the advantageous features and all the advantages need to be incorporated into every implementation of the present disclosure.

[0088] In the Summary and in the Detailed Description, and the Claims, and in the accompanying drawings, reference is made to particular features (including method operations) of the present disclosure. It is to be understood that the disclosure in this specification includes all possible combinations of such particular features. For example, where a particular feature is disclosed in the context of a particular aspect, implementation, implementation, or example of the present disclosure, or a particular claim, that feature can also be used, to the extent possible in combination with and / or in the context of other particular aspects and implementations of the present disclosure, and in the present disclosure generally.

[0089] Implementations and all of the functional operations described in this specification can be implemented in digital electronic circuitry, or in computer software, firmware, or hardware, including the structural means disclosed in this specification and structural equivalents thereof, or in combinations of them. Implementations described herein can be implemented as one or more non-transitory computer program products, i.e. , one or more computer programs tangibly embodied in a machine readable storage device, for execution by, or to control the operation of, data processing apparatus, e.g., a programmable processor, a computer, or multiple processors or computers.

[0090] The processes and logic flows described in this specification can be performed by one or more programmable processors executing one or more computer programs to perform functions by operating on input data and generating output. The processes and logic flows can also be performed by, and apparatus can also be implemented as, special purpose logic circuitry, e.g., an FPGA (field programmable gate array) or an ASIC (application specific integrated circuit).

[0091] The term “data processing apparatus” encompasses all apparatus, devices, and machines for processing data, including by way of example a programmable processor, a computer, or multiple processors or computers. The apparatus caninclude, in addition to hardware, code that creates an execution environment for the computer program in question, e.g., code that constitutes processor firmware, a protocol stack, a database management system, an operating system, or a combination of one or more of them. Processors suitable for the execution of a computer program include, by way of example, both general and special purpose microprocessors, and any one or more processors of any kind of digital computer.

[0092] Computer readable media suitable for storing computer program instructions and data include all forms of nonvolatile memory, media and memory devices, including by way of example semiconductor memory devices, e.g., EPROM, EEPROM, and flash memory devices; magnetic disks, e.g., internal hard disks or removable disks; magneto optical disks; and CD ROM and DVD-ROM disks. The processor and the memory can be supplemented by, or incorporated in, special purpose logic circuitry.

[0093] The term “comprises” and grammatical equivalents thereof are used herein to mean that other components, ingredients, operations, etc. are optionally present. For example, an article “comprising” (or “which comprises”) components A, B, and C can consist of (i.e., contain only) components A, B, and C, or can contain not only components A, B, and C but also one or more other components. In addition, whenever a composition, an element or a group of elements is preceded with the transitional phrase “comprising” or grammatical equivalents thereof, it is understood that it is contemplated that the same composition or group of elements may be preceded with transitional phrases “consisting essentially of,” “consisting of,” “selected from the group of consisting of,” or “is” preceding the recitation of the composition, element, or elements and vice versa.

[0094] Where reference is made herein to a method comprising two or more defined operations, the defined operations can be carried out in any order or simultaneously (except where the context excludes that possibility), and the method can include one or more other operations which are carried out before any of the defined operations, between two of the defined operations, or after all of the defined operations (except where the context excludes that possibility).

[0095] When introducing elements of the present disclosure or exemplary aspects or implementation(s) thereof, the articles “a,” “an,” “the” and “said” are intended to mean that there are one or more of the elements.

[0096] While the foregoing is directed to implementations of the present disclosure, other and further implementations of the disclosure may be devised without departing from the basic scope thereof, and the scope thereof is determined by the claims that follow.

Claims

What is claimed is:1 . A method of making an electrode, comprising: transferring a flexible support layer stack comprising a flexible support layer and an alkali metal film formed over the flexible support layer to a flexible substrate stack, the flexible substrate stack comprising a current collector substrate; patterning the alkali metal film by exposing the alkali metal film to a laser beam, the laser beam directed toward a backside of the flexible support layer; and removing the flexible support layer to form a patterned electrode structure.

2. The method of claim 1 , wherein exposing the alkali metal film to the laser beam induces an alkali metal transfer process creating a void volume between the alkali metal film and the flexible support layer.

3. The method of claim 2, wherein the laser beam is produced by an infrared laser source.

4. The method of claim 1 , wherein the laser beam is a continuous laser beam produces by a solid-state laser source.

5. The method of claim 1 , wherein the laser beam is a pulsed laser beam produced by a solid-state laser.

6. The method of claim 1 , wherein the flexible substrate stack further comprises a lithiophilic film formed over the current collector substrate.

7. The method of claim 6, wherein the lithiophilic film is selected from Al, Au, Ag, Bi, Pt, Zn, Si, Sn, Mg, In, Ga, or Cu, alloys thereof.

8. The method of claim 6, wherein the lithiophilic film is selected from Li4Ti5O12, Lio.388Tao.238Lao.475Cl3, XLi20-MCIy, wherein M = Ta, Hf, 0.8<x<2, and y = 4 or 5, LnOCI, wherein Ln= rare earth metal, RENiO3, AIOx, CuO, ZnO, CoO, or MnO.

9. The method of claim 1 , wherein the flexible support layer stack further comprises a release layer formed in between the flexible support layer and the alkali metal film.

10. The method of claim 1 , wherein the flexible support layer comprises a material selected from polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polyimide (PI), poly(methyl methacrylate) (PMMA), cellulose tri-acetate (TAC), polypropylene (PP), polyethylene (PE), polycarbonates (PC), multilayers thereof, or a combination thereof.11 . The method of any of claims 1 to 10, wherein the alkali metal film is lithium.

12. An anode structure, comprising: a current collector; a lithiophilic film formed over the current collector; a patterned alkali metal film formed over the lithiophilic film, the patterned alkali metal film defining a plurality of void volumes separated by the patterned alkali metal film, the void volumes defined by sidewalls of the patterned alkali metal film and a bottom surface; and an alkali metal film deposited into the void volumes of the patterned alkali metal film.

13. The anode structure of claim 12, wherein the lithiophilic film defines the bottom surface.

14. The anode structure of claim 12, wherein the sidewalls of the patterned alkali metal film define a honeycomb structure.

15. The anode structure of claim 12, wherein the lithiophilic film is selected from Al, Au, Ag, Bi, Pt, Zn, Si, Sn, Mg, In, Ga, or Cu, alloys thereof.

16. The anode structure of claim 12, wherein the lithiophilic film is selected from Li4Ti5O12, Lio.388Tao.238Lao.475Cl3, XLi2O-MCIy, wherein M = Ta, Hf, 0.8<x<2, and y = 4 or 5, LnOCI, wherein Ln= rare earth metal, RENiO3, AIOx, CuO, ZnO, CoO, or MnO.

17. The anode structure of any of claims 12-16, wherein the alkali metal film is lithium.

18. The anode structure of claim 17, wherein the patterned alkali metal film is lithium.

19. An energy storage device, comprising: a cathode electrode structure; and the anode structure of any of claims 12 to 16.

20. The energy storage device of claim 19, further comprising: a separator film.21 . The energy storage device of claim 20, wherein the cathode electrode structure comprises a cathode film and a cathode current collector.

22. A method of making an electrode, comprising: transferring a flexible support layer stack comprising a flexible support layer and a first alkali metal film formed over the flexible support layer to a flexible substrate stack, the flexible substrate stack comprising a current collector substrate and a lithiophilic film formed over the current collector substrate; patterning the first alkali metal film by exposing the first alkali metal film to a laser beam, the laser beam directed toward a backside of the flexible support layer; removing the flexible support layer to form a patterned alkali metal film, the patterned alkali metal film defining a plurality of void volumes separated by the patterned alkali metal film, the void volumes defined by sidewalls of the patterned alkali metal film and a bottom surface; and depositing an alkali metal film into the void volumes via an electroplating process.

23. The method of claim 22, wherein the lithiophilic film defines the bottom surface of the void volumes.

24. The method of claim 22, wherein the sidewalls of the patterned alkali metal film define a honeycomb structure.

25. The method of claim 22, wherein the lithiophilic film is selected from Al, Au, Ag, Bi, Pt, Zn, Si, Sn, Mg, In, Ga, or Cu, alloys thereof.

26. The method of claim 22, wherein the lithiophilic film is selected from Li4Ti5012, Lio.388Tao.238Lao.475Cl3, XLi20-MCIy M = Ta, Hf, 0.8<x<2, y = 4 or 5, LnOCI; Ln= rare earth metal, RENiO3, AIOx, CuO, ZnO, CoO, or MnO.

27. The method of any of claims 22-26, wherein the alkali metal film is lithium.

28. The method of anode structure of claim 27, wherein the patterned alkali metal film is lithium.

Images