WO2025231386A1

WO2025231386A1 - Lithium metal passivation to reduce local temperature rise during pre‑lithiation

Info

Publication number: WO2025231386A1
Application number: PCT/US2025/027535
Authority: WO
Inventors: Thomas Humphreys; Subramanya P. Herle; Jean Delmas
Original assignee: Elevated Materials Us LLC
Current assignee: Elevated Materials Us LLC
Priority date: 2024-05-03
Filing date: 2025-05-02
Publication date: 2025-11-06
Anticipated expiration: 2026-11-03

Abstract

Described herein are techniques for transferring a film stack from a substrate onto a copper foil to form a substrate, and an apparatus for transferring the same. In one embodiment, a method for transferring a film from a substrate, including depositing a passivation layer over a surface of the film, the passivation layer comprising one or more of a dielectric material, a metal material, and an organic material; and applying a surface of the passivation layer to a surface of an anode.

Description

LITHIUM METAL PASSIVATION TO REDUCE LOCAL TEMPERATURE RISE DURING PRE-LITHIATION

BACKGROUND

Field

[0001] Embodiments of the present disclosure generally relate to energy storage devices and methods and apparatus for manufacturing energy storage devices. More particularly, the present disclosure generally relates to methods and apparatus for processing of alkali metal surfaces.

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] Like the heavy element homologs of the first main group, alkali metals such as lithium are characterized by a strong reactivity with a variety of substances. Lithium reacts violently with water, alcohols and other substances that contain protic hydrogen, often resulting in ignition. Lithium is unstable in air and reacts with oxygen, nitrogen and carbon dioxide. Lithium is normally handled under an inert gas atmosphere (noble gases such as argon) and the strong reactivity of lithium entails that other processing operations also be performed in an inert gas atmosphere. As a result, lithium provides several challenges when it comes to processing, storage, and transportation.

[0004] Therefore, there is a need for methods and apparatus for the deposition and processing of alkali metals used in energy storage devices.

SUMMARY

[0005] Described herein are techniques for transferring a film stack from a substrate onto a copper foil to form a substrate, and an apparatus for transferring the same. In one embodiment, a method for transferring a film from a substrate, including depositing a passivation layer over a surface of the film, the passivation layer comprising one or more of a dielectric material, a metal material, and an organic material; and applying a surface of the passivation layer to a surface of an anode.

[0006] In another embodiment, a device for transferring a film stack from a substrate, including a film layer deposited over a surface of a carrier layer; a passivation layer deposited over a surface of the film layer, the passivation layer comprising one or more of a dielectric material, a metal material, and an organic material.

[0007] In yet another embodiment, a device for transferring a film stack from a substrate, including a film layer deposited over a surface of a carrier layer; a passivation layer formed of a material and deposited over a surface of the film layer, the passivation layer is deposited via at least one deposition mechanism, the at least one deposition mechanism, including depositing the passivation layer via vacuum evaporation, depositing the passivation layer via melt coating, depositing the passivation layer via spray coating, or depositing the passivation layer via extrusion; and an anode deposited over a surface of the passivation layer, the material of the passivation layer comprising one or more of a dielectric material, a metal material, and an organic material, the material of the passivation layer is equal or greater than 95% of the atomic weight of the passivation layer.

BRIEF DESCRIPTION OF THE DRAWINGS

[0008] 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 embodiments, some of which are illustrated in the appended drawings. It is to be noted, however, that the appended drawings illustrate only exemplary embodiments and are therefore not to be considered limiting of its scope, may admit to other equally effective embodiments.

[0009] FIG. 1 shows a film stack according to at least one embodiment of the present disclosure.

[0010] FIG. 2A is a flowchart showing selected operations of a method of forming a film stack according to at least one embodiment of the present disclosure.

[0011] FIG. 2B is an illustration of film stacks during operations of the method of FIG. 2A according to at least one embodiment of the present disclosure.

[0012] FIG. 3 shows a side cross-sectional view of a flexible substrate processing system according to at least one embodiment of the present disclosure. [0013] 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 embodiment may be beneficially incorporated in other embodiments without further recitation.

DETAILED DESCRIPTION

[0014] Embodiments of the present disclosure generally relate to energy storage devices and methods and apparatus for manufacturing energy storage devices. More particularly, the present disclosure generally relates to methods and apparatus for processing of alkali metal surfaces.

[0015] Substrate independent direct transfer (SIDT) is a method to pre-lithiate anodes in energy storage devices, or to lithiate copper current collectors in energy storage devices, in order to improve the life cycles of the batteries. In SIDT processes, lithium is first deposited on a support layer (e.g., a carrier film) composed of one or more materials such as polyethylene terephthalate (PET), paper, or combinations thereof. The materials on the support layer are directly transferred to the anode for pre-lithiation.

[0016] During SIDT, the intercalation of lithium and graphite, as well as the alloying of lithium and silicon cause a variety of exothermic reactions. These exothermic reactions are exacerbated by the reactivity of metallic lithium. While such exothermic reactions may assist in the pre-lithiation process including an anode material (for example, graphite, Si, etc.), uncontrolled exothermic reactions increase the risks of localized rapid diffusion (i.e. hot spots) on the film stack during the pre-lithiation process, which in turn can impact device integration. Therefore, uncontrolled exothermic reactions are not desirable, as hot spots may cause non-uniformity across resultant anodes. By reducing the intercalation rate and reducing temperature, hot spots can distribute heat generation over a longer time period which allows for the temperature of the material to be controlled.

[0017] The present disclosure relates to a method and system for transferring a lithium film from a carrier film (for example, a polyethylene terephthalate (PET) substrate) to an anode film. More specifically, the present disclosure utilizes a coating process that applies a passivation layer to a surface of a lithium layer. The passivation layer reduces temperature rise of the anode during SIDT processes. Therefore, by implementing the coating process, heat generation that occurs during SIDT may be distributed over a longer time period, thus reducing intercalation rate and reducing temperature hot spots across the anode. [0018] Although embodiments of the present disclosure are described with respect to lithium, it is contemplated that embodiments described herein apply to other alkali metals, such as sodium.

Example Substrate

[0019] FIG. 1 illustrates a schematic cross-sectional view of one implementation of a film stack 100. The film stack 100 can be a device or a portion of a device. The film stack 100 includes a substrate 102 having a bottom surface 102a and a top surface 102b. In some cases, the substrate 102 may a flexible carrier 310 or a flexible substrate 330. The film stack 100 further includes an alkali metal-containing layer 104 (for example, a lithium- containing layer, a sodium-containing layer, a lithium alloy, or sodium alloy) having a bottom surface 104a disposed on the top surface 102b of the substrate 102. The substrate 102 may be made of suitable materials, such as PET, paper, copper, or combinations thereof. The substrate 102 may be a carrier film. The film stack 100 further includes a passivation layer 106 having a top surface 106b and a bottom surface 106a, the bottom surface 106a disposed on the top surface 104b of the alkali metal-containing layer 104.

[0020] The passivation layer 106 serves to, for example, protect the alkali metalcontaining layer 104 from unwanted reactions that can affect the performance of the substrate, when, for example, the film stack 100 is used as a battery (or a portion of a battery).

[0021] The passivation layer 106 disposed on the top surface 104b of the alkali metalcontaining layer 104 can be an ultra-thin layer. A thickness of the passivation layer 106 can be greater than 0 nm, about 200 nm or less, or combinations thereof, such as from about 0.1 nm to about 200 nm, such as from about 1 nm to about 150 nm, such as from about 10 nm to about 100 nm, or from about 0.5 nm to about 50 nm, such as from about 1 nm to about 40 nm, such as from about 2 nm to about 30 nm, such as from about 3 nm to about 20 nm, such as from about 4 nm to about 10 nm, though other thicknesses are contemplated. Any of the foregoing numbers can be used singly to describe an open- ended range or in combination to describe a close-ended range.

[0022] In some embodiments, the passivation layer 106 can have an impedance (regardless of thickness) that is greater than 0 ohms (Q) about 500 Q or less, or combinations thereof, such as less than about 450 Q, such as less than about 400 Q, such as less than about 350 Q, such as less than about 300 Q, such as less than about 250 Q, such as less than about 200 Q, such as less than about 150 Q, such as less than about 100 Q, such as less than about 75 Q, such as less than about 50 Q, though other values are contemplated. Any of the foregoing values can be used singly to describe an open-ended range or in combination to describe a close-ended range. In at least one embodiment, the passivation layer 106 can have an impedance (regardless of thickness) that is about 100 Q or less, such as about 90 Q or less, such as about 80 Q or less, such as about 70 Q or less, such as about 60 Q or less, such as about 50 Q or less, such as about 40 Q or less, such as about 30 Q or less, such as about 20 Q or less, such as about 10 Q or less. Any of the foregoing numbers can be used singly to describe an open-ended range or in combination to describe a close-ended range.

[0023] The passivation layer 106 can comprise, consist of, or consist essentially of an alkali metal or other metal (such as Ag, Sn, Bi, and/or the alkali metal of the alkali metalcontaining layer 104), reaction product(s) of an alkali metal or other metal with reagent(s), a remainder balance of reagent(s), or combinations thereof. The passivation layer 106 can comprise, consist of, or consist essentially of a dielectric material (such as IJ2CO3, LiF, U2O, AI2O3, ZrO2, and/or combinations thereof). The passivation layer 106 can comprise, consist of, or consist essentially of an organic material (such as high-polymer polyethylene oxide (PEO), polysulphone (PSU), plastic film mulch (PFM), acrylic resins, and/or combinations thereof). Illustrative, but non-limiting, examples of reagent(s) utilized for passivation can include carbon dioxide (CO2), carbon monoxide (CO), hydrogen (H2), oxygen (O2), water vapor, halogen-containing reagents (for example, sulfur hexafluoride (SFe), ammonia (NH3), chlorine-containing gases), among others.

[0024] As described above, the passivation layer 106 can comprise, consist essentially of, or consist of reaction product(s) of an alkali metal (or other metal) with one or more reagents reaction product(s) of an alkali metal or other metal with one or more reagents, a remainder balance of reagent(s), or combinations thereof. Reaction products can include carbonates, halides, oxides, or nitrides of metals; carbonates, halides, oxides, or nitrides of alkali metals, chalcogenides, or com binations thereof, among others. Illustrative, but non-limiting examples of reaction products that can form at least a part of passivation layer 106 can include lithium carbonate (U2CO3), lithium fluoride (LiF), lithium sulfur hexafluoride (LixSFe, wherein x is a number from 0 to 1), lithium carbide (U2C2), AIOx, AIOOH, LisN, U2O, LiAIC>2, Li-ZrC>2, chalcogenides (for example, Bi2Tes), halides (for example, LiX, wherein X = F, Cl, Br), Li4TisOi2, or combinations thereof, among others.

[0025] In some embodiments, CO2 is provided with one or more of argon (Ar), H2, O2, and water vapor to form a passivation layer 106 comprising U2CO3. In at least one embodiment, SFe is provided with one or more of Ar, H2, O2, and water vapor to form a passivation layer 106 comprising LiF and/or LixSFe. In some embodiments, CF4 plasma is provided to form a passivation layer 106 comprising LiF and/or U2C2.

[0026] The passivation layer 106 can be characterized as having high purity. High purity in the context of the passivation layer 106 means that the composition of matter in the passivation layer 106 is greater than about 95% of the atomic weight, such as greater than about 99% of the atomic weight. For example, if the passivation layer is targeted to be U2CO3, the passivation layer will contain less than 1 % of elements other than Li, C, and O. As another example, if the passivation layer is targeted to be LiF, the passivation layer will contain less than 1 % of elements other than Li and F. The high purity can be achieved by, for example, embodiments described herein.

[0027] The film stack 100 can be used in energy storage devices such as batteries. For example, an energy storage device can include an anode and the film stack 100 disposed over the anode.

Example Methods

[0028] Embodiments described herein also relate to methods of forming passivation layers. Generally, and in some embodiments, methods described herein include passivating a surface of an alkali metal-containing layer to improve the thermal quality of the alkali metal-containing layer.

[0029] The alkali metal-containing layer can be part of a substrate such as those made by substrate independent direct transfer (SIDT). SIDT is a method for transferring lithium to either pre-lithiate (or pre-sodiate) anodes or form lithium metal anodes for energy storage devices in order to improve the life cycles of the batteries. These anodes can include, but are not limited to, graphite, silicon, silicon graphite, silicon oxide graphite, silicon, metalized plastic, and copper. In SIDT processes, lithium (or other alkali metal) is first deposited on a support layer or flexible carrier composed of one or more materials such as polyethylene terephthalate (PET), paper, or combinations thereof. The materials on the support layer are directly transferred to the anode for pre-lithiation or a current collector for lithium metal anode formation. A release layer enables transferring lithium and other materials off of the support layer and onto the anode.

[0030] During SIDT, the intercalation of lithium and graphite, as well as the alloying of lithium and silicon cause a variety of exothermic reactions. These exothermic reactions are exacerbated by the reactivity of metallic lithium. While such exothermic reactions may assist in the pre-lithiation process including an anode material (for example, graphite, Si, etc.), uncontrolled exothermic reactions increase the risks of localized rapid diffusion (i.e. hot spots) on the film stack during the pre-lithiation process, which in turn can impact device integration. Therefore, uncontrolled exothermic reactions are not desirable, as hot spots may cause non-uniformity across resultant anodes. By reducing the intercalation rate and reducing temperature, hot spots can distribute heat generation over a longer time period which allows for the temperature of the material to be controlled.

[0031] The present disclosure relates to a method and system for transferring a lithium film from a polyethylene terephthalate (PET) substrate onto a copper foil to form a substrate. More specifically, the present disclosure utilizes a coating process that applies a passivation layer to a surface of a lithium layer to reduce temperature rise of the anode during SIDT processes. By implementing the coating process, heat generation that occurs during SIDT may be distributed over a longer time period, thus reducing intercalation rate and reducing temperature hot spots and non-uniformities across the anode.

[0032] FIG. 2A is a flowchart showing selected operations of a method 200 for forming a passivation layer 106 on an alkali metal-containing layer 104 according to at least one embodiment of the present disclosure. FIG. 2B is an illustration 250 of substrates during operations of the method 200 according to at least one embodiment of the present disclosure.

[0033] The method 200 can be a continuous process where the film stack 260 is in continuous motion such that film stack 100 is formed continuously. The continuous and automated process can simplify the overall manufacturing process and reduce production time and costs associated with production of lithium films on copper foils.

[0034] The method 200 begins with depositing the alkali metal-containing layer 104 onto a substrate 102 (e.g. a carrier film) at operation 205. The alkali metal-containing layer 104 is disposed on the top surface 102b of the substrate 102. The substrate 102 may be a carrier film. In some embodiments, the alkali metal-containing layer 104 contains lithium (Li) or sodium (Na). In some embodiments, the alkali metal-containing layer 104 is deposited onto the substrate 102 using vacuum or thermal evaporation, melt coating, spray coating, extrusion, and/or a combination thereof. In some embodiments, the alkali metal-containing layer 104 is deposited onto the substrate 102 via thermal evaporation and the max width of the deposited layer is less than 800 mm. In some embodiments, the substrate 102 is polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polyimide (PI), cooper (Cu), nickel (Ni), or a combination thereof.

[0035] When the passivation deposition process of operation 210 includes deposition of a passivation layer, such deposition can be achieved by direct deposition of thin films on the top surface 104b of an alkali metal-containing layer (e.g. an alkali metal-containing layer 104) using physical vapor deposition (PVD), by chemical vapor deposition (CVD), or electron beam deposition.

[0036] The deposition process of operation 210 can be a continuous process where the film stack 270 is in continuous motion such that substrate is formed continuously. The deposition process of operation 210 can be performed in any suitable chamber.

[0037] As an example of the deposition process of operation 210, the film stack 260 having the materials 208 disposed thereon is disposed within a suitable chamber. A temperature inside the chamber can be about room temperature or from about 20°C to about 200°C, such as from about 20°C to about 100°C, such as from about 20°C to about 60°C, such as from about 30°C to about 50°C, though other values are contemplated. Any of the foregoing numbers can be used singly to describe an open-ended range or in combination to describe a close-ended range. A pressure inside the chamber can be from about 1x1 O’⁶ Torr to about 1x1 O'² Torr (about 10 mTorr), such as from about 1x1 O'⁵ Torr to about 1x1 O'³ Torr (about 1 mTorr), though other values are contemplated. Alternatively, a pressure inside the chamber can be at about atmospheric pressure, including from about 1x10¹ Torr to about 1x10⁵ Torr, such as from about 1x10², though other values are contemplated. Any of the foregoing numbers can be used singly to describe an open- ended range or in combination to describe a close-ended range. In some examples, a passivation material can be flowed into the chamber to form the passivation layer 106. In some embodiments, the passivation layer 106 is a dielectric material, a metallic material, an organic material, or a combination thereof. In some embodiments, the passivation layer 106 is a dielectric material including U2CO3, LiF, U2O, AI2O3, ZrC>2, and/or a combination thereof. In some embodiments, the passivation layer 106 is a metallic material including Ag, Sn, Bi, and/or a combination thereof. In some embodiments, the passivation layer 106 is an organic material including high-polymer polyethylene oxide (PEO), polysulphone (PSU), plastic film mulch (PPM), acrylic resins, and/or combinations thereof.

[0038] The deposition process of operation 210 can be performed for a duration of less than about 10 minutes (min), such as less than about 5 min, such as less than about 2 min, such as less than about 1 min, such as less than about 30 seconds (s), such as less than about 20 s, such as less than about 10 s, or from about 1 s to about 30 s, such as from about 5 s to about 20 s, though other values are contemplated. Any of the foregoing numbers can be used singly to describe an open-ended range or in combination to describe a close-ended range.

[0039] The deposition process of operation 210 can be pass-by process where the substrate (for example, at least a portion of the film stack 260) is a thin web. The linear dimension described above can be larger than the width of the substrate to assure uniform coverage. In some embodiments, the overlap can be from about 0 cm to about 20 cm, such as from about 5 cm to about 15 cm on either side of the substrate, though other values are contemplated. Any of the foregoing numbers can be used singly to describe an open-ended range or in combination to describe a close-ended range. The process can be a continuous process where the film stack 260 is in continuous motion.

[0040] In some embodiments, passivating the top surface 104b with a passivation material at operation 210 to form the passivation layer 106 can be facilitated by vacuum evaporation, melt coating, spray coating, extrusion, and the like. In one example, surface passivation 284 can include treating top surface 104b of the film stack 270 with a gas to form the passivation layer 106, depositing a passivation layer 106 on the top surface 104b, or combinations thereof using a source 282 to form the film stack 100. The passivation material of the passivation layer 106 may reduce heat generation between the alkali metal-containing layer 104 and an anode where the passivation layer 106 is intercalated between the alkali metal-containing layer 104 and the anode.

[0041] The deposition during operation 210 can be accomplished using the same or similar methods and parameters described above with respect to operation 205.

[0042] The passivation layer 106 formed by operation 210 can include an alkali metal (such as the alkali metal of the alkali metal-containing layer 104), reaction product(s) of an alkali metal with reagent(s), a remainder balance of reagent(s), or combinations thereof. The passivation layer 106 can comprise, consist of, or consist essentially of a dielectric material (such as U2CO3, Li F, U2O, AI2O3, ZrC , and/or combinations thereof). The passivation layer 106 can comprise, consist of, or consist essentially of an organic material (such as high-polymer polyethylene oxide (PEO), polysulphone (PSU), plastic film mulch (PFM), acrylic resins, and/or combinations thereof). Illustrative, but nonlimiting, examples of reagent(s) utilized for passivation can include carbon dioxide (CO2), carbon monoxide (CO), hydrogen (H2), oxygen (O2), water vapor, halogen-containing reagents (for example, sulfur hexafluoride (SFe), ammonia (NH3), chlorine-containing gases), among others.

[0043] Illustrative, but non-limiting, examples of reagent(s) (the passivation processing gas) utilized for passivation can include carbon dioxide (CO2), carbon monoxide (CO), hydrogen (H2), oxygen (O2), water vapor, halogen-containing reagents (for example, sulfur hexafluoride (SFe), ammonia (NH3), chlorine-containing gases), among others. Besides these gases, a non-reactive gas such as Ar, He, Ne, Kr, Xe, N2, or combinations thereof can be flowed into a cleaning unit to facilitate formation of the passivation layer 106.

[0044] As described above, the passivation layer 106 can comprise, consist essentially of, or consist of reaction product(s) of an alkali metal (or other metal) with one or more reagents reaction product(s) of an alkali metal or other metal with one or more reagents, a remainder balance of reagent(s), or combinations thereof. Reaction products can include carbonates, halides, oxides, or nitrides of metals; carbonates, halides, oxides, or nitrides of alkali metals, chalcogenides, or com binations thereof, among others. Illustrative, but non-limiting examples of reaction products that can form at least a part of passivation layer 106 can include Li2CO3, LiF, LixSFe (wherein x is a number from 0 to 1 ), U2C2, AIOx, AIOOH, LisN, U2O, UAIO2, Li-ZrO2, chalcogenides (for example, Bi2Tes), halides (for example, LiX, wherein X = F, Cl, Br), Li4TisOi2, or combinations thereof, among others.

[0045] In some embodiments, CO2 is provided with one or more of argon (Ar), H2, O2, and water vapor to form a passivation layer 106 comprising U2CO3. In at least one embodiment, SFe is provided with one or more of Ar, H2, O2, and water vapor to form a passivation layer 106 comprising LiF and/or LixSFe. In some embodiments, CF4 plasma is provided to form a passivation layer 106 comprising LiF and/or U2C2. [0046] The method 200 continues at operation 215. At operation 215, the passivation layer 106 is applied to an anode surface (e.g. a surface of anode). Application may be performed, for example, via lamination at rollers 382/383 illustrated in FIG. 3. The passivation material of the passivation layer 106 may reduce heat generation between the alkali metal-containing layer 104 and anode where the passivation layer 106 is intercalated between the alkali metal-containing layer 104 and the anode.

[0047] The application process of operation 215 may occur after a film stack 100 is dried and mounted onto one or more unwinds (e.g., unwinds 315/325 of FIG. The film stack 100 may be dried at about 350ppm or less, such as about 300ppm or less, 250ppm or less, such as about 200ppm or less, such as about 150ppm or less, such as about 100 ppm or less, such as about 100ppm or less, though other values are contemplated.

[0048] Once the anode is sandwiched between the alkali metal-containing layers 104 (e.g. flexible carriers 310, 320) and the passivation layer 106 via the passing through of the lamination rollers 382/383 illustrated in FIG. 3, the alkali metal-containing layers 104 will begin to diffuse into the anode. The passivation layer 106 reduces the rate of lithium diffusion or reduce the likelihood of localized rapid diffusion (i.e. hot spots). The rate of alkali metal-containing layer diffusion (e.g. lithium diffusion) may be lowered to between about 5 nm of Li/min to about 30 nm of Li/min, such as between about 10 nm of Li/min to about 15 nm of Li/min.

Example Processing Chamber

[0049] The present disclosure relates to a method and system for transferring a lithium metal film from a substrate (e.g. a carrier film like PET) to an anode film. One exemplary use of the processing systems and methods provided in this disclosure include removing a release layer within an atmospheric plasma chamber to enable passivation of a surface of a lithium film that can be used as part of an electrode in a lithium ion-battery. For example, a lithium film can be transferred from a flexible carrier (for example, a polymer- based carrier) to a flexible substrate (for example, a flexible copper substrate) by having the flexible carrier and the flexible substrate pass through a calendering unit (e.g., the processing system 300 illustrated in FIG. 3) and then peeling away the flexible carrier. During calendering, the intercalation of the lithium film with an anode surface may cause a variety of exothermic reactions. Such exothermic reactions may be not be desirable, as hot spots and local thermal maxima may cause non-uniformity across the lithium film deposited on the anode. [0050] FIG. 3 shows a side cross-sectional view of a flexible substrate processing system 300 according to at least one embodiment of the present disclosure. The processing system 300 includes equipment for transferring lithium films on a first flexible carrier 310 and a second flexible carrier 320 to each side of a flexible substrate 330, so that the flexible substrate 330 with the lithium films can be used as an electrode (for example, anode) in a lithium-ion battery. The processing system 300 includes a calendering unit 340 to transfer the lithium films on the flexible carriers 310, 320 to the flexible substrate 330.

[0051] The processing system 300 includes a first flexible carrier supply hub 315. A supply roll 311 of the first flexible carrier 310 is positioned on the first flexible carrier supply hub 315. In some embodiments, the first flexible carrier 310 can be formed of a polymer material, such as polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polyimide (PI), or combinations thereof. A lithium film (not shown in FIG. 3) is positioned on the lower side 310L of the first flexible carrier 310, so that this lithium film faces an upper surface 330U of the flexible substrate 330 as the first flexible carrier 310 and the flexible substrate 330 are conveyed through the calendering unit 340. The upper surface 330LI of the flexible substrate 330 is on an opposite side relative to a lower surface 330L of the flexible substrate 330. The upper surface 330LI is also referred to as the first surface or the first side of the flexible substrate 330 while the lower surface is also referred to as the second surface or the second side of the flexible substrate 330.

[0052] The processing system 300 includes a second flexible carrier supply hub 325. A supply roll 321 of the second flexible carrier 320 is positioned on the second flexible carrier supply hub 325. In some embodiments, the second flexible carrier 320 can be formed of a same material (for example, PET) as the first flexible carrier 310. A lithium film (not shown in FIG. 3) is positioned on the upper side 320U of the second flexible carrier 320, so that this lithium film faces the lower surface 330L of the flexible substrate 330 as the second flexible carrier 320 and the flexible substrate 330 are conveyed through the calendering unit 340.

[0053] In some embodiments, the lithium films on the first flexible carrier 310 and the second flexible carrier 320 can be formed of lithium metal, another alkali metals or an alloy including an alkali metal.

[0054] The processing system 300 includes a flexible substrate supply hub 335. A supply roll 331 of the flexible substrate 330 is positioned on the flexible substrate supply hub 335. In some embodiments, the flexible substrate 330 can be formed of one or more of copper, graphite, silicon, silicon graphite, silicon oxide graphite, silicon, metalized plastic, or other materials.

[0055] The processing system 300 further includes the calendering unit 340. The calendering unit 340 includes a first calender roller 341 and a second calender roller 342. The first flexible carrier 310, the second flexible carrier 320, and the flexible substrate 330 are arranged to be conveyed along a path that extends between the first calender roller 341 and the second calender roller 342. The flexible substrate 330 is positioned between the first flexible carrier 310 and the second flexible carrier 320 when the first flexible carrier 310, the second flexible carrier 320, and the flexible substrate 330 are conveyed between the first calender roller 341 and the second calender roller 342. The calender rollers 341 , 342 exert a high amount of pressure on the flexible carriers 310, 320 and the flexible substrate 330 that causes the lithium film on each of the flexible carriers 310, 320 to be transferred to the flexible substrate 330.

[0056] The processing system 300 includes a first flexible carrier pickup hub 316. A pickup roll 312 of the first flexible carrier 310 is positioned on the first flexible carrier pickup hub 316. The lithium film is no longer on the first flexible carrier 310 when the first flexible carrier 310 is wound onto the first flexible carrier pickup hub 316 because the lithium film previously on the first flexible carrier 310 is transferred onto the flexible substrate 330 by the calendering unit 340.

[0057] The processing system 300 includes a second flexible carrier pickup hub 326. A pickup roll 322 of the second flexible carrier 320 is positioned on the second flexible carrier pickup hub 326. The lithium film is no longer on the second flexible carrier 320 when the second flexible carrier 320 is wound onto the second flexible carrier pickup hub 326 because the lithium film previously on the second flexible carrier 320 is transferred onto the flexible substrate 330 by the calendering unit 340.

[0058] The processing system 300 includes a flexible substrate pickup hub 336. A pickup roll 332 of the flexible substrate 330 is positioned on the flexible substrate pickup hub 336. The flexible substrate 330 includes a lithium film on each of the upper surface 330U and the lower surface 330L of the flexible substrate 330. These lithium films are transferred from the respective flexible carriers 310, 320 onto the flexible substrate 330 by the calendering unit 340. [0059] The processing system 300 further includes a plurality of rollers 381-388. In some embodiments, each of the rollers 381-388 can be passive rollers. The rollers 381 - 388 can assist in applying proper tension to and assist in changing the direction of the flexible carriers 310, 320 and the flexible substrate 330 during the movement of each of the flexible carriers 310, 320 and the flexible substrate 330 through the different portions of the processing system 300. Some of the rollers 381-388 can also assist in moving the flexible carriers 310, 320 closer to or further away from the flexible substrate 330. For example, the second and third rollers 382, 383 assist in bringing the flexible carriers 310, 320 into contact with the flexible substrate 330 before the flexible carriers 310, 320 and the flexible substrate 330 are conveyed through the calendering unit 340. Additionally, the fourth and fifth rollers 384, 385 provide a location at which tension can be applied to the flexible carriers 310, 320 to peel these flexible carriers 310, 320 away from the flexible substrate 330. In some embodiments, one or more of the rollers 381-388 can instead be a bar, such as metal bar, that can apply tension to the carrier or flexible substrate during the movement of the carrier or flexible substrate.

[0060] The processing system 300 can further include actuators (not shown) configured to rotate each of the hubs 315, 316, 325, 326, 335, 336, so that the flexible carriers 310, 320 and the flexible substrate 330 can be conveyed from the corresponding supply hub 315, 325, 335, through the calendering unit 340, and to the corresponding pick hub 316, 326, 336. The processing system 300 can further include one or more actuators (not shown) to rotate the calender rollers 341 , 342 of the calendering unit 340. The rotational speed of the actuators can be adjusted to control the speed at which the flexible substrate 330 and flexible carriers 310, 320 are conveyed through the processing system 300.

[0061] In the processing system 300, the flexible substrate 330 is conveyed along a path from the supply roll 331 that is supported by the supply hub 335, past the first roller 381 , between the second and third rollers 382, 383, between the calender rollers 341 , 342, between the fourth and fifth rollers 384, 385, past the eighth roller 388, and to the pickup roll 332 around the pickup 336. The flexible substrate pickup hub 336 is configured to rotate and assist in conveying the flexible substrate after the flexible substrate 330 passes between the first calender roller 341 and the second calender roller 342. Similarly, the pickup hubs 316, 326 are configured to rotate and assist in conveying the flexible carriers along paths between the flexible carrier supply hubs 315, 325 and the pickup hubs 316, 326.

[0100] The processing system 300 can also include a controller 305 for controlling processes performed by the processing system 300. The controller 305 can be any type of controller used in an industrial setting, such as a programmable logic controller (PLC). The controller 305 includes a processor 307, a memory 306, and input/output (I/O) circuits 308. The controller 305 can further include one or more of the following components (not shown), such as one or more power supplies, clocks, communication components (for example, network interface card), and user interfaces typically found in controllers for semiconductor equipment.

[0062] The memory 306 can include non-transitory memory. The non-transitory memory can be used to store the programs and settings described below. The memory 306 can include one or more readily available types of memory, such as read only memory (ROM) (for example, electrically erasable programmable read-only memory (EEPROM), flash memory, floppy disk, hard disk, or random access memory (RAM) (for example, non-volatile random access memory (NVRAM).

[0063] The processor 307 is configured to execute various programs stored in the memory 306 such as a program configured to execute methods described herein. During execution of these programs, the controller 305 can communicate to I/O devices through the I/O circuits 308. For example, during execution of these programs and communication through the I/O circuits 308, the controller 305 can control outputs (for example, the actuators connected to the different hubs and the calendering unit 340). The memory 306 can further include various operational settings used to control the processing system 300.

[0064] In one embodiment, a method for transferring a film from a substrate, including depositing a passivation layer over a surface of the film, the passivation layer comprising one or more of a dielectric material, a metal material, and an organic material; and applying a surface of the passivation layer to a surface of an anode.

[0065] The film is a lithium film. The passivation layer further comprises one or more of Li, Al, and Zr. The passivation layer further comprises U2CO3, LiF, U2O, AI2O3, ZrC>2, or some combination thereof. The passivation layer further comprises Ag, Sn, Bi, or some combination thereof. The passivation layer further comprises high-polymer polyethylene oxide (PEO), polysulphone (PSU), plastic film mulch (PFM), acrylic resins, or some combination thereof. Depositing the passivation layer includes depositing the passivation layer via vacuum evaporation; depositing the passivation layer via melt coating; depositing the passivation layer via spray coating; or depositing the passivation layer via extrusion. Applying the surface of the passivation layer comprises laminating the surface of the passivation layer onto the anode at a calendering unit. Removing the substrate from a second surface of the film.

[0066] In another embodiment, a device for transferring a film stack from a substrate, including a film layer deposited over a surface of a carrier layer; a passivation layer deposited over a surface of the film layer, the passivation layer comprising one or more of a dielectric material, a metal material, and an organic material.

[0067] The film layer is a lithium film layer. The passivation layer further comprises one or more of Li, Al, and Zr. The passivation layer further comprises Li2COs, LiF, U2O, AI2O3, ZrC>2, or some combination thereof. The passivation layer further comprises Ag, Sn, Bi, or some combination thereof. The passivation layer further comprises high- polymer polyethylene oxide (PEO), polysulphone (PSU), plastic film mulch (PFM), acrylic resins, or some combination thereof. The passivation layer is deposited via at least one deposition mechanism, the at least one deposition mechanism including depositing the passivation layer via vacuum evaporation; depositing the passivation layer via melt coating; depositing the passivation layer via spray coating; or depositing the passivation layer via extrusion. A surface of the passivation layer is laminated onto a surface of an anode at a calendering unit. The carrier layer is removable.

[0068] In yet another embodiment, a device for transferring a film stack from a substrate, including a film layer deposited over a surface of a carrier layer; a passivation layer formed of a material and deposited over a surface of the film layer, the passivation layer is deposited via at least one deposition mechanism, the at least one deposition mechanism, including depositing the passivation layer via vacuum evaporation, depositing the passivation layer via melt coating, depositing the passivation layer via spray coating, or depositing the passivation layer via extrusion; and an anode deposited over a surface of the passivation layer, the material of the passivation layer comprising one or more of a dielectric material, a metal material, and an organic material, the material of the passivation layer is equal or greater than 95% of the atomic weight of the passivation layer. [0069] The material comprises Li2CO3, LiF, U2O, AI2O3, ZrC>2, Ag, Sn, Bi, polyethylene oxide (PEO), polysulphone (PSU), plastic film mulch (PPM), acrylic resins, or some combination thereof.

[0070] 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.

[0071] 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).

[0072] Embodiments of the present disclosure generally relate to substrates for electronic devices and to methods of forming substrates. Substrates described herein can have superior device performance relative to conventional technologies. Methods described herein are reproducible and can yield uniform passivation layers. Further, embodiments described herein can enable, for example, streamlined material handling and integration and longer shelf life for the passivated substrates (passivated film rolls) than conventional technologies.

[0073] As is apparent from the foregoing general description and the specific aspects, while forms of the aspects have been illustrated and described, various modifications can be made without departing from the spirit and scope of the present disclosure. Accordingly, it is not intended that the present disclosure be limited thereby. Likewise, the term “comprising” is considered synonymous with the term “including.” Likewise whenever a composition, process operation, process operations, an element or a group of elements is preceded with the transitional phrase “comprising,” it is understood that we also contemplate the same composition or group of elements with transitional phrases “consisting essentially of,” “consisting of,” “selected from the group of consisting of,” or “is” preceding the recitation of the composition, process operation, process operations, element, or elements and vice versa, such as the terms “comprising,” “consisting essentially of,” “consisting of” also include the product of the combinations of elements listed after the term.

[0074] For purposes of this present disclosure, and unless otherwise specified, all numerical values within the detailed description and the claims herein are modified by “about” or “approximately” the indicated value, and consider experimental error and variations that would be expected by a person having ordinary skill in the art. For the sake of brevity, only certain ranges are explicitly disclosed herein. However, ranges from any lower limit may be combined with any upper limit to recite a range not explicitly recited, as well as, ranges from any lower limit may be combined with any other lower limit to recite a range not explicitly recited, in the same way, ranges from any upper limit may be combined with any other upper limit to recite a range not explicitly recited. For example, the recitation of the numerical range 1 to 5 includes the subranges 1 to 4, 1.5 to 4.5, 1 to 2, among other subranges. As another example, the recitation of the numerical ranges 1 to 5, such as 2 to 4, includes the subranges 1 to 4 and 2 to 5, among other subranges. Additionally, within a range includes every point or individual value between its end points even though not explicitly recited. For example, the recitation of the numerical range 1 to 5 includes the numbers 1 , 1.5, 2, 2.75, 3, 3.80, 4, 5, among other numbers. Thus, every point or individual value may serve as its own lower or upper limit combined with any other point or individual value or any other lower or upper limit, to recite a range not explicitly recited.

[0075] As used herein, the indefinite article “a” or “an” shall mean “at least one” unless specified to the contrary or the context clearly indicates otherwise. For example, aspects comprising “a layer” includes aspects comprising one, two, or more layers, unless specified to the contrary or the context clearly indicates only one layer is included.

[0076] While the foregoing is directed to aspects of the present disclosure, other and further aspects 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 for transferring a film from a substrate, comprising: depositing a passivation layer over a surface of the film, the passivation layer comprising one or more of a dielectric material, a metal material, and an organic material; and applying a surface of the passivation layer to a surface of an anode.

2. The method of claim 1 , wherein the film is a lithium film.

3. The method of claim 1 , wherein the passivation layer further comprises one or more of Li, Al, and Zr.

4. The method of claim 3, wherein the passivation layer further comprises Li2COs, LiF, Li2<D, AI2O3, ZrO2, or some combination thereof.

5. The method of claim 1 , wherein the passivation layer further comprises Ag, Sn, Bi, or some combination thereof.

6. The method of claim 1 , wherein the passivation layer further comprises high- polymer polyethylene oxide (PEO), polysulphone (PSU), plastic film mulch (PFM), acrylic resins, or some combination thereof.

7. The method of claim 1 , wherein depositing the passivation layer comprises: depositing the passivation layer via vacuum evaporation; depositing the passivation layer via melt coating; depositing the passivation layer via spray coating; or depositing the passivation layer via extrusion.

8. The method of claim 1 , wherein applying the surface of the passivation layer comprises laminating the surface of the passivation layer onto the anode at a calendering unit.

9. The method of claim 8, further comprising removing the substrate from a second surface of the film.

10. A device for transferring a film stack from a substrate, comprising: a film layer deposited over a surface of a carrier layer; a passivation layer deposited over a surface of the film layer, the passivation layer comprising one or more of a dielectric material, a metal material, and an organic material.

11 . The device of claim 10, wherein the film layer is a lithium film layer.

12. The device of claim 10, wherein the passivation layer further comprises one or more of Li, Al, and Zr.

13. The device of claim 12, wherein the passivation layer further comprises Li2CO3, LiF, U2O, AI2O3, ZrO2, or some combination thereof.

14. The device of claim 10, wherein the passivation layer further comprises Ag, Sn, Bi, or some combination thereof.

15. The device of claim 10, wherein the passivation layer further comprises high- polymer polyethylene oxide (PEO), polysulphone (PSU), plastic film mulch (PFM), acrylic resins, or some combination thereof.

16. The device of claim 10, wherein the passivation layer is deposited via at least one deposition mechanism, the at least one deposition mechanism comprising: depositing the passivation layer via vacuum evaporation; depositing the passivation layer via melt coating; depositing the passivation layer via spray coating; or depositing the passivation layer via extrusion.

17. The device of claim 10, wherein a surface of the passivation layer is laminated onto a surface of an anode at a calendering unit.

18. The device of claim 10, wherein the carrier layer is removable.

19. A device for transferring a film stack from a substrate, comprising: a film layer deposited over a surface of a carrier layer; a passivation layer formed of a material and deposited over a surface of the film layer, the passivation layer is deposited via at least one deposition mechanism, the at least one deposition mechanism comprising: depositing the passivation layer via vacuum evaporation, depositing the passivation layer via melt coating, depositing the passivation layer via spray coating, or depositing the passivation layer via extrusion; and an anode deposited over a surface of the passivation layer, the material of the passivation layer comprising one or more of a dielectric material, a metal material, and an organic material, the material of the passivation layer is equal or greater than 95% of the atomic weight of the passivation layer.

20. The device of claim 19, wherein the material comprises Li2CO3, LiF, l_i2O, AI2O3, ZrO2, Ag, Sn, Bi, polyethylene oxide (PEO), polysulphone (PSU), plastic film mulch (PFM), acrylic resins, or some combination thereof.