Seed layer for lithium transfer and passivation

Abstract

Embodiments of this disclosure generally relate to methods for forming film stacks for electronic devices and film stacks including lithium anodes and pre-lithified anodes for energy storage devices. The method includes forming a seed layer on a flexible support layer and depositing a lithium metal layer on the seed layer. The method also includes laminating the lithium metal layer onto a flexible receiving substrate and separating the lithium metal layer from the flexible support layer. The seed layer functions as a release layer for the lithium metal layer. At least a portion of the seed layer is transferred together with the lithium metal layer, resulting in passivation of the lithium metal layer.

Description

[Technical Field]

[0001] background field

[0001] Implementations of the present disclosure generally relate to film stacks for electronic devices and methods for forming film stacks. [Background technology]

[0002] Description of related technologies

[0002] Large-capacity electrochemical energy storage devices such as lithium-ion (Li-ion) batteries are being used in an increasing number of applications, including portable electronic devices, medical devices, transportation equipment, grid-connected large-scale energy storage, renewable energy storage, and uninterruptible power supplies (UPS).

[0003]

[0003] The lithium metal layer plays a crucial role in the development of lithium-ion batteries. Lithium is an alkali metal. Like its congeners in Group 1 of the periodic table, lithium is characterized by its strong reactivity with various substances. Lithium reacts violently with water, alcohols, and other substances containing protic hydrogen, often causing ignition. Lithium is unstable in air and reacts with oxygen, nitrogen, and carbon dioxide. Therefore, due to its high reactivity, lithium is usually handled in an inert gas atmosphere (noble gases such as argon). As a result, lithium presents several challenges in processing, storage, and transportation.

[0004]

[0004] Therefore, what is needed in the art is an improved method for transferring lithium metal layers to form a film stack. [Overview of the project]

[0005]

[0005] In one embodiment, a method is provided for forming a seed layer on a flexible support layer. This method includes depositing a lithium metal layer on the seed layer, laminating the lithium metal layer onto a flexible receiving substrate, and separating the lithium metal layer from the flexible support layer to transfer the lithium metal layer to the receiving substrate. When the lithium metal layer is transferred, at least a portion of the seed layer is transferred to the receiving substrate along with the lithium metal layer, and passivation is brought about in the lithium metal layer.

[0006]

[0006] In another embodiment, a method is provided for forming a film stack for an energy storage device. The method includes placing a flexible support layer in a vacuum environment and forming a seed layer on the flexible support layer. The seed layer includes LiF, Li2CO3, Ag, Bi, Sn, Ag+LiF, Bi+LiF, Sn+LiF, AgF, CxFy, or a combination thereof. The method also includes depositing a lithium metal layer on the seed layer, stacking the lithium metal layer onto a flexible receiving substrate, and transferring the lithium metal layer from the flexible support layer to the flexible receiving substrate to form a film stack. The seed layer helps release the lithium metal layer from the flexible support layer, and at least a portion of the seed layer is transferred to the flexible receiving substrate together with the lithium metal layer.

[0007]

[0007] In a further embodiment, a film stack for an energy storage device is provided. The film stack includes a flexible receiving substrate, a lithium metal layer disposed on the flexible receiving substrate, and a seed layer disposed on at least a portion of the lithium metal layer. The seed layer provides passivation to a portion of the lithium metal layer disposed between the seed layer and the flexible receiving substrate. The lithium metal layer and the seed layer are also transferred from the flexible support layer to the flexible receiving substrate, with the seed layer acting as a release layer for separating the lithium metal layer from the flexible support layer.

[0008]

[0008] In order to understand the features of the present disclosure described above in more detail, a more detailed description of the present disclosure, which has been briefly summarized above, can be obtained by referring to the embodiments shown in the accompanying drawings. However, it should be noted that the accompanying drawings are merely illustrative and do not limit the scope of application, and other equally effective implementations are possible. [Brief explanation of the drawing]

[0009] [Figure 1]

[0009] This flowchart shows selected operations for a method of forming an energy storage device by one or more implementations of the present disclosure. [Figure 2A]

[0010] This figure shows the various steps involved in manufacturing an energy storage device according to the method shown in Figure 1, or according to one or more implementations of the present disclosure. [Figure 2B] This figure shows the various steps involved in manufacturing an energy storage device according to the method shown in Figure 1, or according to one or more implementations of the present disclosure. [Figure 2C] This figure shows the various steps involved in manufacturing an energy storage device according to the method shown in Figure 1, or according to one or more implementations of the present disclosure. [Figure 2D] This figure shows the various steps involved in manufacturing an energy storage device according to the method shown in Figure 1, or according to one or more implementations of the present disclosure. [Figure 2E] This figure shows the various steps involved in manufacturing an energy storage device according to the method shown in Figure 1, or according to one or more implementations of the present disclosure. [Figure 2F] This figure shows the various steps involved in manufacturing an energy storage device according to the method shown in Figure 1, or according to one or more implementations of the present disclosure. [Figure 2G] This figure shows the various steps involved in manufacturing an energy storage device according to the method shown in Figure 1, or according to one or more implementations of the present disclosure. [Figure 3]

[0011] FIG. 1 is a flowchart illustrating selected operations of a method of forming an energy storage device in accordance with one or more implementations of the present disclosure. [Figure 4A]

[0012] FIG. 2 is a diagram illustrating various stages of manufacturing an energy storage device in accordance with one or more implementations of the present disclosure, according to the method of FIG. 3. [Figure 4B] FIG. 3 is a diagram illustrating various stages of manufacturing an energy storage device in accordance with one or more implementations of the present disclosure, according to the method of FIG. 3. [Figure 4C] FIG. 4 is a diagram illustrating various stages of manufacturing an energy storage device in accordance with one or more implementations of the present disclosure, according to the method of FIG. 3. [Figure 4D] FIG. 5 is a diagram illustrating various stages of manufacturing an energy storage device in accordance with one or more implementations of the present disclosure, according to the method of FIG. 3. [Figure 4E] FIG. 6 is a diagram illustrating various stages of manufacturing an energy storage device in accordance with one or more implementations of the present disclosure, according to the method of FIG. 3. [Figure 5]

[0013] FIG. 7 shows a schematic diagram of manufacturing an energy storage device in a laminate transfer device according to the method of FIG. 3, which is in accordance with one or more implementations of the present disclosure. [Figure 6]

[0014] FIG. 6 shows a schematic diagram of a flexible substrate coating apparatus in accordance with one or more implementations of the present disclosure. [Figure 7]

[0015] FIG. 8 shows a schematic diagram of a laminate transfer device in accordance with one or more embodiments of the present disclosure. DETAILED DESCRIPTION OF EMBODIMENTS

[0010]

[0016] To facilitate understanding, identical reference numerals have been used, wherever 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 description.

[0011]

[0017] This disclosure generally relates to a process for transferring a metal layer using a release layer. In particular, the implementation relates to a method for using a deposited seed layer configured to function as a release layer and a surface passivation layer when forming an anode film stack.

[0012]

[0018] Transferring lithium metal layers onto a substrate is a crucial process in the microfabrication of microelectronic devices and energy storage devices. Substrate-independent direct transfer (SIDT) is a method for forming an anode film stack by transferring one or more layers, including alkali metal layers (e.g., lithium metal layers), onto a substrate stack (e.g., a current collector), and is used in implementations where lithium metal functions as an anode, or for pre-lithifying anode material already formed on a current collector. Pre-formed anode materials include, but are not limited to, graphite, silicon, silicon graphite, silicon oxide graphite, silicon, or combinations thereof. Current collectors may include or be combinations thereof, such as metallized plastics, copper, or combinations thereof. In the SIDT process, lithium is formed on a flexible support layer stack composed of one or more materials, such as polymer substrates, e.g., polyethylene terephthalate (PET), paper, or combinations thereof. The material formed on the flexible support layer stack is directly transferred / laminated onto the substrate stack. The substrate stack may include, or be, a current collector, a current collector having an anode material formed on the current collector, a metallized plastic substrate, a separator, or a metallized plastic substrate having lithium formed on the metallized plastic substrate.

[0013]

[0019] Conventional methods for transferring materials formed on a flexible support layer stack often utilize a release layer formed between the alkali metal layer and the flexible support layer stack. This release layer allows for the transfer of lithium and other materials from the flexible support layer stack onto the current collector or anode material, if present. Such conventional release layers are often prefabricated on the flexible support layer stack and vary in thickness, delamination pressure, particle size, and pinholes. The variability and uncontrollable properties of the release layer can cause process variations during SIDT (Surface Injection Tissue Transfer). As a result, trace amounts of the release layer and other materials may remain on the lithium surface of the formed film stack after SIDT.

[0014]

[0020] However, release layer materials are often unsuitable for end applications such as electrochemical devices. For example, if the chemical composition of the release layer is not compatible with the end device (e.g., a battery), it can hinder ion and electron transport. In other words, depending on the chemical composition of the release layer, the cell impedance between the anode and separator interface may increase, which is generally undesirable because it can affect the overall performance of the cell. Furthermore, undesirable reactions of the release layer with gases (e.g., H2O, O2, N2, etc.) during handling, transport, and subsequent integration can affect device integration.

[0015]

[0021] A method for depositing both a seed layer, used as a release layer in SIDT to transfer the lithium metal layer, and a surface passivation layer after the lithium metal layer has been transferred, is described below. The SIDT process of this disclosure is illustrated in the implementation shown in Figure 1. In one or more implementations, which can be combined with other implementations, a seed layer is deposited on a flexible support layer in a vacuum chamber before the formation of the lithium metal layer. The seed layer enables a release layer that is tuned to have consistent quality, precise control, and to function as a surface passivation layer during anode film stack formation. Depositing the seed layer in a vacuum also provides an engineered solution for developing a high-quality, clean interface layer and forming an anode film stack without breaking the vacuum.

[0016]

[0022] One or more implementations of this disclosure also provide improved interface control using vacuum deposition without disrupting the vacuum. The method can be incorporated into a roll-to-roll tool and used in the roll-to-roll process described in the implementation shown in Figure 3. Roll-to-roll fabrication of interface layers provides a mass production solution, including substrate-independent deposition and transfer (SIDT) of lithium anode film stacks. High-quality lithium metal can be deposited on a seed layer immediately before stack transfer to maintain the highest quality material in the film stack.

[0017]

[0023] While the specific substrates on which some of the implementations described herein can be carried out are not limited, it should be noted that implementations are particularly beneficial on flexible substrates such as web-based substrates, panels, or individual sheets. Flexible substrates can also be in the form of foils, films, or sheets.

[0018]

[0024] It should also be noted that the flexible substrates or webs used in the implementations described herein generally have the characteristic of being bendable. The term "web" may be used synonymously with the terms "strip," "flexible substrate," or "flexible conductive substrate." For example, the web in the implementations described herein may be made of a polymer material.

[0019]

[0025] Figure 1 shows a flowchart of Method 100 for manufacturing an energy storage device according to one or more implementations of the present disclosure. Figures 2A to 2G illustrate the various stages of manufacturing an energy storage device according to Method 100 of Figure 1. Method 100 describes forming a SIDT stack 255 on a flexible support layer 210, and then transferring the SIDT stack 255 to a receiving substrate 260 to form an anode film stack 265. Although Figures 2A to 2G are described in relation to Method 100, it will be understood that the structures disclosed in Figures 2A to 2G are not limited to Method 100 and may exist independently as structures separate from Method 100. Similarly, although Method 100 is described in relation to Figures 2A to 2G, it will be understood that Method 100 is not limited to the structures disclosed in Figures 2A to 2G and may instead exist independently of the structures disclosed in Figures 2A to 2G.

[0020]

[0026] Figures 2A–2G show only partial schematic diagrams of energy storage devices, and it should be understood that energy storage devices may include any number of additional layers and / or additional materials common to energy storage devices, which are not shown for brevity. It should also be noted that while method 100 shown in Figure 1 is described in order, other process sequences, including one or more operations, which may be omitted and / or added, and / or rearranged in a different preferred order, are also included within the scope of implementation of the disclosures provided herein.

[0021]

[0027] Referring to Figure 2A, in operation 101, a flexible support layer 210 of the flexible support layer stack 200 is provided. The flexible support layer 210 has a front side 210f (also referred to as the front surface) and a back side 210b (also referred to as the back surface) opposite to the front side 210f. The flexible support layer 210 may contain any suitable material that conforms to the target processing conditions.

[0022] In some implementations, the flexible support layer comprises multiple sublayers. In one or more implementations, which can also be combined with other implementations, the flexible support layer 210 may be or may contain one or more layers selected from plastics, polymer materials, metallized plastics, metals, paper, multilayers thereof, or combinations thereof. Examples of suitable polymer materials include polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polyimide (PI), poly(methyl methacrylate) (PMMA), cellulose triacetate (TAC), polypropylene (PP), polyethylene (PE), polycarbonate (PC), multilayers thereof, or combinations thereof.

[0023]

[0029] In one or more implementations that can be combined with other implementations, the flexible support layer 210 has a thickness in the range of approximately 1 micron to approximately 100 microns, or in the range of approximately 1 micron to approximately 100 microns, or in the range of approximately 10 microns to approximately 50 microns, or in the range of approximately 25 microns to approximately 50 microns.

[0024]

[0030] Referring to Figure 2B, in operation 102, a seed layer 220 is formed on the flexible support layer 210. The seed layer 220 is formed on the front side 210f of the flexible support layer 210. The seed layer 220 has a front side 220f (also referred to as the front surface) and a back side 220b (also referred to as the back surface) opposite to the front side 220f. In one or more mounting configurations, the seed layer 220 is formed on the front side 210f of the flexible support layer 210 such that the back side 220b of the seed layer 220 is in contact with the front side 210f of the flexible support layer 210. In other mounting configurations, the flexible support layer 210 may be pre-fabricated with a release layer placed on the front surface 210f. In such a mounting configuration, the seed layer 220 is formed on the release layer placed on the flexible support layer 210.

[0025]

[0031] The seed layer 220 may be any material suitable for releasing the SIDT stack 255 from the flexible support layer 210 during the SIDT process and subsequently providing a passivation layer for the SIDT stack 255, or may include such materials. By depositing the seed layer 220 on the flexible support layer 210 and then depositing an alkali metal layer (e.g., lithium metal layer 250) to form the SIDT stack 255, the seed layer 220 used can be freely controlled, thereby achieving both improved manufacturing efficiency and improved electrochemical performance of the formed SIDT stack 255. For example, in some implementations, the alkali metal layer may be deposited in direct contact with the seed layer 220. Thus, the chemical properties and reactions between the seed layer 220 and the subsequently deposited alkali metal layer can be controlled so as not to result in an ohmic layer that increases the cell impedance between the anode and the separator as a result of reactions between the seed layer 220 or between the seed layer 220 and the layers of the SIDT stack 255.

[0026]

[0032] In one or more implementations, a seed layer 220 formed to passivate an alkali metal layer (e.g., a lithium metal layer 250 in a SIDT stack 255) may be configured such that the electrochemical interaction between the seed layer 220 and the lithium metal layer 250 deposited thereon improves the electrochemical performance of the SIDT stack in the energy storage device. For example, the seed layer 220 may be configured not to interfere with ion or electron transport in the battery cell structure, thereby reducing the impedance of the resulting anode film stack to approximately 200 ohms / cm². 2 It can be maintained at less than 5 ohms / cm². In some embodiments, the seed layer 220 reduces the impedance of the formed anode film stack to approximately 5 ohms / cm². 2 and approximately 200 ohms / cm 2 Maintain it during this time.

[0027]

[0033] In one or more implementations, which may also be combined with other implementations herein, the seed layer 220 may be selected from LiF, Li2CO3, Ag, Bi, Sn, Ag+LiF, Bi+LiF, Sn+LiF, AgF, CxFy, or a combination thereof. The composition of the seed layer 220 may also be selected based on the specific battery chemistry and application in which the formed anode film stack will be used. In one or more implementations, which may also be combined with other implementations, the material of the seed layer 220 may be selected and adjusted based on its chemical properties and reactions with the alkali metal layer deposited on the seed layer 220, as well as the specific battery chemistry and application in which the formed anode film stack is intended to be used.

[0028]

[0034] Any suitable method can be used to form the seed layer 220 in front of the flexible support layer 210. In some implementations, the seed layer 220 can be deposited using vapor deposition techniques such as sputtering, reactive sputtering, evaporation, physical vapor deposition (PVD), chemical vapor deposition (CVD), plasma vapor deposition (PECVD), or other similar vapor deposition processes. In one or more implementations, which can also be combined with other implementations, the seed layer 220 is deposited using a mixed process gas of argon and carbon dioxide. Forming the seed layer 220 by vapor deposition techniques allows for control of the seed layer 220's thickness, delamination pressure, particles, and pinholes, ensuring consistent, predictable, and high-quality lithium transfer. For example, in one or more implementations, deposition of the seed layer 220 by vapor deposition in a vacuum allows for control of the provided flexible support layer 210 and the formation of the seed layer 220 formed on it. Such control makes it possible to mitigate and reduce potential particle and pinhole defects caused by the flexible support layer 210 during the deposition of the seed layer 220.

[0029]

[0035] In one or more implementations, the polymer material of the flexible support layer 210 and / or seed layer 220 is selected so that the SIDT stack 255 is released from the flexible support layer 210 by pressure-initiated lift-off. In other implementations, the seed layer 220 may be configured to be released by laser-initiated lift-off. Without being bound by theory, it is thought that a seed layer 220 with weak interlayer bonding would then allow the seed layer 220 to be easily separated from the flexible support layer 210. In one or more implementations, the seed layer 220 is approximately 0.3 gram force / cm 2 and approximately 16 grams / cm² 2 It can consist of the release pressure between them.

[0030]

[0036] The seed layer 220 can also be deposited under atmospheric conditions, near atmospheric conditions, or vacuum conditions. In one or more implementations, the seed layer 220 can be deposited using a vacuum process in a vacuum environment such as a vacuum chamber. In one implementation, the seed layer 220 is about 1×10 -3 mbar and about 1×10 -6 between mbar (e.g., about 1×10 -2 less than mbar or about 1×10 -4 less than mbar) in a vacuum environment. In some implementations, prior to operation 102, the flexible support layer 210 can be transferred to a vacuum coating system, for example, the flexible substrate coating apparatus 600 shown in FIG. 6. The seed layer 220 can then be deposited under vacuum in a roll-to-roll deposition system using the flexible substrate coating apparatus 600.

[0031]

[0037] In some implementations, the seed layer 220 includes a single layer of material deposited on the flexible support layer 210, and the seed layer 220 can be separated from the flexible support layer 210 during SIDT, and then functions as a passivation layer. In other implementations, the seed layer 220 can include a plurality of sub-layers of different materials deposited on the flexible support layer 210. In such implementations, to facilitate release of the SIDT stack 255 from the flexible support layer 210, specific sub-layers of the seed layer 220 may be configured to separate from each other during SIDT. In such implementations, the sub-layer of the seed layer 220 transferred together with the SIDT stack 255 can then function as a surface passivation layer for the SIDT stack 255.

[0032]

[0038] In one or more implementations, which can also be combined with other implementations herein, the seed layer 220 has a thickness in the range of about 1 nm to about 5,000 nm, for example, about 10 nm to about 1,000 nm and about 100 nm to about 500 nm. In some implementations, the seed layer 220 includes multiple sublayers, each having a thickness of about 50 nm or less. In one or more implementations, the thickness of the seed layer 220 may be adjusted based on the delamination pressure desired to separate the SIDT stack 255 from the flexible support layer 210.

[0033]

[0039] In one or more implementations, which can also be combined with other implementations described herein, the seed layer 220 can be patterned or selectively deposited to create localized lithium deposition areas for customized battery designs. Since the seed layer 220 functions as a release layer for separating the SIDT stack 255 from the flexible support layer 210 during SIDT, the seed layer 220 can be patterned or selectively deposited to perform localized interfacial releases to transfer the corresponding SIDT stack 255 to the receiving substrate 260. In one or more implementations, which can also be combined with other implementations described herein, the seed layer 220 can be patterned or selectively deposited on the flexible support layer 210 to transfer the lithium metal layer 250 onto the receiving substrate 260.

[0034]

[0040] Referring to Figure 2C, optionally, in operation 103, a solid electrolyte layer 230 is formed on the seed layer 220. The solid electrolyte layer 230 has a front side 230f (also referred to as the front) and a back side 230b (also referred to as the back) opposite to the front side 230f. In one or more implementations, the solid electrolyte layer 230 is deposited on the front side 220f of the seed layer 220, and is formed such that the back side 230b of the solid electrolyte layer 230 is in contact with the front side 220f of the seed layer 220. Any suitable method may be used to form the solid electrolyte layer 230 on the front side 220f of the seed layer 220. The solid electrolyte layer 230 may be deposited using a non-vacuum coating technique.

[0035]

[0041] The solid electrolyte layer 230 may contain any suitable material that is suitable for the target ion conduction. In some implementations, the solid electrolyte layer 230 may contain or be a metal salt such as a lithium salt. The lithium salt may be one or more of the following: LiPF6, LiAsF6, LiCF3SO3, LiN(CF3SO3)3, LiBF6, LiClO4BETTE electrolyte, or a combination thereof. The electrolyte may be in a gel or polymer matrix medium.

[0036]

[0042] In one or more implementations, the solid electrolyte layer 230 is made of fluorine-based compounds (PTFE, PVDF), LiF, Li2CO3, MgO, AlOx, AlHO2, RENiO3 (RE = rare earth element), BN, BaTiO3, Li4Ti5O12, ZrO2, TiO2, silicon-doped lithium tantalum phosphate, for example, Li(1+x)Ta2P(1-x)SixO8, Li1.5Ta2P0.5Si0.5O8, lithium tantalum phosphate, for example, LiTa2PO8 (LTPO The material may be selected from or contain combinations thereof, such as Li2Ta2SiO8 (LTSO), Li0.34La0.56TiO3, lithium aluminum titanium phosphate, for example Li1.3Al0.3Ti1.7(PO4)3 (LATP), lithium aluminum germanium phosphate, for example Li1.3Al0.3Ge1.7(PO4)3 (LAGP), garnet Li7La3Zr2O12 (LLZO), or other materials.

[0037]

[0043] In one or more implementation configurations, the solid electrolyte layer 230 may be formed using non-vacuum coating techniques. Suitable coating techniques include, but are not limited to, slot die coating processes, doctor blade coating processes, three-dimensional (3D) printing processes, or a combination thereof. In one or more alternative implementation configurations, the solid electrolyte layer 230 may be formed using vacuum coating techniques. In some implementation configurations, the solid electrolyte layer 230 can be deposited using a flexible substrate coating apparatus 600 as shown in Figure 6.

[0038]

[0044] Referring to Figure 2D, optionally, in operation 104, one or more interface layers 240 are formed on the solid electrolyte layer 230. The interface layer 240 is positioned between the seed layer 220 and the lithium metal layer 250. The interface layer 240 may include at least one of an interface dielectric material, a plating and stripping promoting layer, and a lithiophilic layer. The interface layer 240 can be deposited under vacuum. The interface layer 240 can be deposited under vacuum in a roll-to-roll deposition system, for example, the solid electrolyte layer 230 can be deposited using the flexible substrate coating apparatus 600 shown in Figure 6. The interface layer 240 can be deposited by vapor deposition techniques, such as chemical vapor deposition (CVD), atomic layer deposition (ALD), physical vapor deposition (PVD), for example, thermal evaporation or sputtering.

[0039]

[0045] The interfacial dielectric layer may be selected from AlOx, AlOOH, LiF, BaTiO3, ZrO2, TiO2, Li4Ti5O12, LiAlO2, AlF3, BiF3, AgFx, rare earth (RE) nickelate (RENiO3), or a combination thereof. RE can be a trivalent rare earth element. RE can be a lanthanide. RE can be selected from La, Pr, Nd, Sm, Eu, Gd, Dy, Ho, Er, Y, Lu, or a combination thereof. RE can be selected from Sm, Nd, and Eu. RE nickelate can be doped with ions. Suitable ions for doping include lithium ions, sodium ions, magnesium ions, cassium ions, hydrogen ions, and aluminum ions. In one example, the RE nickelate is SmNiO3 doped with lithium ions. The flaking and stripping promoting layer may be an alloy of a metal or chalcogenide, or may contain such an alloy. The plating and stripping accelerating layer may be or contain Ag, Bi, Sn, Si, Cu, or an alloy or chalcogenide of Ag, Bi, Sn, Si, Cu, or a combination thereof. The lithiumophilic layer may be a metal containing Al, Au, Ag, Bi, Pt, Zn, Si, Sn, Mg, In, Ga, or Cu, an alloy thereof, or at least one of Li4Ti5O12, RENiO3, AlOx, CuO, ZnO, CoO, or MnO.

[0040]

[0046] In one or more embodiments, which can be combined with other implementations, one or more interface layers 240 include a dielectric layer. The dielectric layer may be lithium fluoride, aluminum oxide, aluminum hydroxide, boron nitride, carbon nitride, titanium oxide, lithium titanate, zirconium oxide, tantalum oxide, barium titanate, lithium zirconium oxide, molybdenum oxide, silicon oxide, lithium silicon oxide, or a combination thereof.

[0041]

[0047] In one or more embodiments, which can also be combined with other embodiments, one or more interface layers 240 include a plating and stripping accelerating layer(s). The plating and stripping accelerating layer(s) may include a metal layer. The metal layer may be silver, bismuth, tin, copper, aluminum, silicon, or a combination thereof. The plating and stripping accelerating layer(s) may include a metal layer. The metal layer may be silver, bismuth, tin, copper, aluminum, silicon, indium, gallium, or a combination thereof. The plating and stripping accelerating layer may be Ag, Bi, Sn, Si, Cu, Al, or a metal or chalcogenide of Ag, Bi, Sn, Si, or a combination thereof.

[0042]

[0048] In one or more embodiments, which can also be combined with other embodiments, one or more interface layers 240 include a lithiophilic layer. One lithiophilic layer may allow for the lateral growth of a lithium metal layer 250 that is subsequently deposited. The lithiophilic layer may be a metal or a metal oxide, or may contain one. The lithiophilic layer may be a metal including Al, Au, Ag, Bi, Pt, Zn, Si, Sn, Mg, In, Ga, or Cu, an alloy thereof, or at least one of Li4Ti5O12, RENiO3, AlOx, CuO, ZnO, CoO, or MnO, or may contain at least one of them. The lithiophilic layer may be deposited by at least one process selected from the group consisting of dipping, spin coating, dip coating, spray coating, doctor blade coating, solution casting, droplet coating, PVD, and CVD.

[0043]

[0049] In one or more implementations, which can be combined with other implementations, the passivation layer may be optionally included in the SIDT stack 255, for example, by being formed before the deposition of the lithium metal layer 250. By forming surface passivation within the SIDT stack 255 before the deposition of the lithium metal layer 250, the lithium metal layer 250 is immediately protected (e.g., by the surface passivation layer) after the SIDT stack 255 has been stacked and transferred to the receiving substrate 260. As described above, the seed layer 220 may be configured to function as a release layer for separating the SIDT stack 255 from the flexible support layer 210 during the stacking and transfer of the lithium metal layer 250. At least a portion of the seed layer 220 is configured to be transferred to the receiving substrate 260 together with the SIDT stack 255, resulting in the passivation of the anode film stack 265 that is subsequently formed. Therefore, the seed layer 220 described herein can improve manufacturing efficiency by eliminating the need for the additional step of forming a passivation layer before depositing the lithium metal layer 250, while also providing similar benefits and advantages in that it forms a passivation layer for the anode film stack 265 that is formed.

[0044]

[0050] Referring to Figure 2E, in operation 105, a lithium metal layer, such as lithium metal layer 250, is formed on the front side 220f of seed layer 220. The lithium metal layer 250 includes a front side 230f (also referred to as the front surface) and a back side 230b (also referred to as the back surface) opposite to the front side 230f. In some implementations, if a solid electrolyte layer 230 and one or more interface layers 240 are present, the lithium metal layer 250 may be formed directly on the layer below, for example, the solid electrolyte layer 230 and one or more interface layers 240. In implementations where a solid electrolyte layer 230 and one or more interface layers 240 are not present, the lithium metal layer 250 may be formed directly on the front side 220f of seed layer 220.

[0045]

[0051] The lithium metal layer 250 may be lithium, or may contain lithium, and can be deposited under vacuum. The lithium metal layer 250 can be deposited under vacuum in a roll-to-roll volumetric system, such as the flexible substrate coating apparatus 600 shown in Figure 6. In some implementations, operations 102 to 105 can all be performed using the same flexible substrate coating apparatus 600 shown in Figure 6, which allows the seed layer 220 and the SIDT stack 255 formed thereon to be deposited on the flexible support layer 210 without breaking the vacuum. The lithium metal layer 250 can be deposited by physical vapor deposition methods, such as vapor deposition or sputtering. The evaporation process may be an electron beam evaporation process or a thermal evaporation process.

[0046]

[0052] Referring to Figure 2E, the lithium metal layer 250 completes the flexible support layer stack 200. The seed layer 220, solid electrolyte layer 230 (if present), one or more interface layers 240 (if present), and lithium metal layer 250 form the SIDT stack 255. In some implementations, the SIDT stack 255 may consist of only a portion of the seed layer 220.

[0047]

[0053] The SIDT stack 255 described herein is formed such that the lithium metal layer 250 is deposited last on the flexible support layer stack 200. Depositing the lithium layer last makes it possible to form the SIDT stack 255 without damaging the lithium layer, which has a lower melting point than other materials formed in the energy storage device. Conventional methods for forming energy storage devices include the direct deposition of molten lithium onto a current collector in lithium metal anode formation or onto an anode material in pre-lithiumized mounting. These methods further include maintaining the underlying substrate while the lithium metal layer 250 is formed to prevent damage to the lithium. In contrast, the flexible support layer stack 200 and method described herein allow the lithium metal layer 250 to be formed immediately before transferring the SIDT stack 255 to the receiving substrate 260 during operation 106.

[0048]

[0054] In some implementations, which can be combined with other implementations, a passivation layer can be optionally included in the SIDT stack 255. In some implementations, the passivation layer contains alkali metal carbonates in an alkali metal-containing layer (e.g., lithium metal layer 250). In some implementations, which can be combined with other implementations, the alkali metal-containing layer is a lithium metal layer, for example, lithium metal layer 250, in which case the passivation layer contains lithium carbonate. The passivation layer can be formed by exposing the lithium metal layer 250 to carbon dioxide. In some implementations, the lithium metal layer 250 is exposed to carbon dioxide in the presence of heat. Without being bound by theory, it is assumed that carbon dioxide reacts with the lithium metal to form a thin layer of lithium carbonate on the exposed surface of the lithium metal layer 250. In some implementations, the lithium carbonate metal passivation layer, for example, the lithium carbonate passivation layer, can have a thickness in the range of approximately 50 nm to approximately 100 nm. The lithium carbonate passivation layer can function as a protective layer for the lithium metal layer 250. For example, the lithium carbonate metal passivation layer can protect the lithium metal layer 250 from oxidation and damage during storage and transport.

[0049]

[0055] After and before operation 105, the flexible support layer stack 200 including the SIDT stack 255 may be transferred from a vacuum coating system, such as the flexible substrate coating apparatus 600 shown in Figure 6, to a lamination transfer apparatus, such as the lamination transfer apparatus 700 shown in Figure 7. The lamination transfer process includes applying the receiving substrate 260 to the front side 250f of the lithium metal layer 250 and removing the SIDT stack 255 from the flexible support layer 210 to form the anode film stack 265. As described above, removing the SIDT stack 255 from the flexible support layer 210 may include separating the seed layer 220 from the flexible support layer 210, or separating a specific sublayer of the seed layer 220.

[0050]

[0056] Referring to Figure 2G, in operation 106, the SIDT stack 255 is transferred from the flexible support layer 210 to the receiving substrate 260, forming the anode film stack 265. As shown in the figure, operation 106 includes transferring the laminate onto the current collector to form the anode film stack 265. In some implementations, if pre-lithiation is performed, the anode material is already formed on the receiving substrate 260, and the lithium metal layer 250 is transferred to the anode material formed on the receiving substrate 260. The receiving substrate 260 may be, or may include, a flexible film such as a CPP film (i.e., cast polypropylene film), an OPP film (i.e., oriented polypropylene film), or a PET film (i.e., polyethylene terephthalate film). Alternatively, the receiving substrate 260 may be pre-coated paper, polypropylene (PP) film, PEN film, polylactic acid (PLA) film, or PVC film. The receiving substrate 260 may be one or more current collectors, or may contain them, and the current collectors may include aluminum (Al), copper (Cu), zinc (Zn), nickel (Ni), cobalt (Co), manganese (Mn), chromium (Cr), stainless steel, clad materials, alloys thereof, and combinations thereof. In various mountings, the receiving substrate 260 may be copper or copper foil, or may contain it.

[0051]

[0057] In one or more implementations, which can be combined with other implementations, the seed layer 220 is transported together with or partially transported with the SIDT stack 255 during operation 106, as shown in Figure 2F. As described above, once the seed layer 220 is transferred, it also functions as a surface passivation layer for the anode film stack 265. The seed layer 220 can function as a protective layer for the lithium metal layer 250. For example, the seed layer 220 can protect the lithium metal layer 250 from oxidation and damage during storage and transport.

[0052]

[0001] Referring to Figure 2G, in operation 107, the anode film stack 265 can optionally be combined with a separator 290, a cathode stack 285, or both the separator 290 and the cathode stack 285 to form an energy storage device 295. In some embodiments, the energy storage device 295 is shown as a planar structure in Figure 2G, but it can also be formed into a cylindrical shape by rolling a stack of layers, and furthermore, other cell configurations (e.g., prismatic cells, button-shaped cells, or stacked electrode cells) can be formed.

[0053]

[0002] Separator 290 may be a microporous polymer separator containing a polyolefin, although this is not an exhaustive example. The polyolefin may be a homopolymer (derived from a single monomer component) or a heteropolymer (derived from multiple monomer components) and may be linear or branched. When a heteropolymer is derived from two monomer components, the polyolefin can take any copolymer chain arrangement, such as a block copolymer or a random copolymer. Similarly, when the polyolefin is a heteropolymer derived from three or more monomer components, it may be a block copolymer or a random copolymer. In certain implementations, the polyolefin may be polyethylene (PE), polypropylene (PP), a blend of PE and PP, or a multilayer porous film of PE and / or PP. Commercially available polyolefin porous membranes include CELGARD® 2500 (single-layer polypropylene separator) and CELGARD® 2320 (triple-layer polypropylene / polyethylene / polypropylene separator), both available from Celgard LLC.

[0054]

[0003] In one or more implementations that can be combined with other implementations, the cathode stack 285 includes a cathode current collector 280 and a cathode material 270. The cathode current collector 280 may be any of the flexible films described above, aluminum (Al), copper (Cu), zinc (Zn), nickel (Ni), cobalt (Co), tin (Sn), silicon (Si), manganese (Mn), magnesium (Mg), alloys thereof, and combinations thereof, or may include them. The cathode current collector 280 may be any of the aluminum (Al), copper (Cu), zinc (Zn), nickel (Ni), cobalt (Co), tin (Sn), silicon (Si), manganese (Mn), magnesium (Mg), alloys thereof, and combinations thereof, or may include them. In some implementations, the cathode current collector 280 may be aluminum or may include aluminum.

[0055]

[0004] The cathode material 270 may be any suitable cathode material or may include any suitable cathode material.

[0040] The cathode material 270 or cathode may be any material compatible with the anode or may include such material, and may include interlayer compounds, insertion compounds, or electrochemically active polymers. Suitable interlayer insertion materials include, for example, sulfur, lithium-containing metal oxides, MoS2, FeS2, MnO2, TiS2, NbSe3, LiCoO2, LiNiO2, LiMnO2, LiMn2O4, V6O 13 and V2O5 are examples. Suitable polymers include, for example, polyacetylene, polypyrrole, polyaniline, and polythiophene. In some implementations, the cathode material 270 includes the polymer binder material described herein. The cathode material 270 or cathode may be a layered oxide such as lithium cobalt oxide, olivine such as lithium iron phosphate, or spinel such as lithium manganese oxide, or may contain these. Examples of lithium-containing oxides include layered oxides such as lithium cobalt oxide (LiCoO2), or LiNi x Co 1-2xMnO2 [wherein x is zero or a non-zero number]LiNiMnCoO2("NMC"), LiNi 0.5 Mn 1.5 O4, Li(Ni 0.8 Co 0.15 Al 0.05 Examples include mixed metal oxides such as O2 and LiMn2O4, and doped lithium-rich layered materials. Examples of phosphates include iron olivine (LiFePO4) and its variants (LiFe (1-x) Mg x PO4 (where x is zero or a non-zero number), LiCoPO4, LiNiPO4, Li3V2(PO4)3, LiVOPO4, LiMP2O7, or LiFe 1.5 P2O7 is one example. Examples of fluoride phosphates include LiVPO4F, LiAlPO4F, and Li5V(PO4). 2G2 Li5Cr(PO4) 2G2 Examples include Li2CoPO4F or Li2NiPO4F. An example of a silicate is Li 2G It may contain eSiO4, Li2MnSiO4, or Li2VOSiO4. An example of a non-lithium compound is Na5V2(PO4). 2G3 It is either or may include them.

[0056]

[0005] Figure 3 shows a flowchart of Method 300 for manufacturing an energy storage device according to one or more implementations of the present disclosure. Figures 4A to 4F illustrate the various stages of manufacturing an energy storage device according to Method 300 of Figure 3. Although Figures 4A to 4E are described in relation to Method 300, it will be understood that the structures disclosed in Figures 4A to 4E are not limited to Method 300 and may instead be independent structures independent of Method 300. Similarly, although Method 300 is described in relation to Figures 4A to 4E, it will be understood that Method 300 is not limited to the structures disclosed in Figures 4A to 4E and may instead be independent of the structures disclosed in Figures 4A to 4E.

[0057]

[0006] Figures 4A to 4E show only partial schematic diagrams of the energy storage device, and it should be understood that the energy storage device may include any number of additional layers and / or additional materials common to energy storage devices, which are not shown for brevity. It should also be noted that although method 300 shown in Figure 3 is described in order, other process sequences including one or more operations, which may be omitted and / or added and / or rearranged in a different preferred order, are also included within the scope of implementation of the disclosures provided herein.

[0058]

[0007] Referring to Figure 4A, in operation 301, a flexible support layer stack 400 is provided. The flexible support layer stack 400 includes at least a flexible support layer 410, a seed layer 420, and a lithium metal layer 430. The flexible support layer 410, seed layer 420, and lithium metal layer 430 correspond to the flexible support layer 210, seed layer 220, and lithium metal layer 250 described herein in relation to Method 100. The seed layer 420 may be placed on top of the flexible support layer 410 as described in operation 102. The lithium metal layer 430 may be placed on top of the seed layer 420 as described in operation 105.

[0059]

[0008] After operation 301, the flexible support layer stack 400 on which the lithium metal layer 430 or SIDT stack 435 is formed is transferred from the vacuum coating system, for example, the flexible substrate coating apparatus 600 shown in Figure 6, to the laminate transfer apparatus, for example, the laminate transfer system 700 shown in Figure 7. The laminate transfer process includes applying the receiving substrate to the front side 430f of the lithium metal layer 430 and removing the flexible support layer 410 from the SIDT stack 435 to form the anode film stack 465.

[0060]

[0009] In one or more implementations, which can be combined with other implementations, optionally in operation 302, the flexible support layer stack 400 on which the lithium metal layer 430 is formed is subjected to a preheating process before the lamination process in operation 303. As shown in Figure 4B, the preheating process involves exposing the lithium metal layer 430 to thermal energy, for example, thermal energy 438 supplied by an infrared lamp light source is used. In some implementations where the lithium metal layer 430 is a thicker layer, preheating the lithium metal layer 430 can facilitate or accelerate the lamination process. In some implementations, the preheating temperature may be in the range of about 30 degrees Celsius and about 200 degrees Celsius. In some implementations, the preheating time may be between about 1 second and about 90 seconds. However, the preheating time may vary based on the speed at which the receiving substrate 440 and the flexible support layer 410 are transported through the lamination transport system 700. For example, in some implementations, the receiving substrate 440 and the flexible support layer 410 can be transported through the laminate transport system 700 at speeds between approximately 0.2 meters / min and approximately 25 meters / min, for example, between approximately 0.5 meters / min and approximately 10 meters / min.

[0061]

[0010] Referring to Figure 4C, in operation 303, the lithium metal layer 430 is laminated onto the receiving substrate 440. The receiving substrate 440 may include one or more layers. In some implementations, for example, in the case of a lithium metal anode device, the receiving substrate 440 may include a current collector. In some implementations, for example, in the case of a prelithiation process, the receiving substrate 440 may include an anode material formed on the current collector. In yet another implementation, the receiving substrate 440 may be or include a separator and / or cathode stack (e.g., separator 290 and cathode stack 285), as shown in Figure 2G.

[0062]

[0011] In one or more mountings, which can be combined with other mountings, the receiving substrate 440 includes a web-based substrate, for example, the current collector may be a web-based substrate. Any suitable current collector may be used. The current collector may be, but is not limited to, aluminum (Al), copper (Cu), zinc (Zn), nickel (Ni), cobalt (Co), manganese (Mn), chromium (Cr), stainless steel, clad material, metallized plastic, paper, stainless steel, metal mesh, metal foil, or a combination thereof. Any suitable anode material may be used. The anode material may be, but is not limited to, graphite, silicon, silicon graphite, silicon oxide graphite, silicon, or a combination thereof.

[0063]

[0012] In the lamination process of operation 303, the lithium metal layer 430 is brought into contact with the receiving substrate 440. For example, as shown in Figure 4C, the front side 430f of the lithium metal layer 430 is in contact with the surface of the receiving substrate 440. In some implementations, if the receiving substrate 440 contains only a current collector, the front side 430f of the lithium metal layer 430 is in contact with the surface of the current collector. In some implementations, if the receiving substrate 440 contains an anode material, the front side 430f of the lithium metal layer 430 is in contact with the surface of the anode material to pre-lithify the anode material.

[0064]

[0013] In some implementations, operations 302 and 303 may occur simultaneously, sequentially, or partially overlapping.

[0065]

[0014] Referring to Figure 4D, optionally, in operation 304, pressure is applied to one or more of the receiving substrate 440 and the flexible support layer stack 200 having a lithium metal layer 430 formed on the flexible support layer stack, so that the receiving substrate 440 is laminated onto the lithium metal layer 430. In some implementations, when method 300 is performed with a roll-to-roll tool, web tension alone is sufficient to laminate the lithium metal layer 430 onto the receiving substrate 440, and no additional pressure is required. In some implementations, additional pressure is used to laminate the lithium metal layer 430 onto the receiving substrate 440, but the lamination process involves pressing the lithium metal layer 430 onto the receiving substrate 440 with a pressure large enough to adhere the lithium metal layer 430 to the receiving substrate 440 without damaging it. In other words, the pressure is such that the lithium metal layer 430 is not mechanically destroyed or degraded by cracking, shattering, etc.

[0066]

[0015] Pressure can be applied using appropriate techniques. In one or more implementations, pressure is applied by a calendering process. The calendering process may include using a pair of calendering rollers 442a, 442b, as shown in Figure 4D. For example, pressure may be applied to the back side 410b of the flexible support layer 410 and the back side 440b of the receiving substrate 440. In one or more other implementations, pressure is applied by a vacuum source. In another one or more implementations, the pressure is external pressure. In one or more implementations, the pair of calendering rollers 442a, 442b may be heated.

[0067]

[0016] In some implementations, operations 303 and 304 may occur simultaneously, sequentially, or partially overlapping.

[0068]

[0017] Referring to Figure 4E, in operation 305, the flexible support layer 410 is separated from the SIDT stack 435, and the anode film stack 465 is formed on the receiving substrate 440. When the flexible support layer 410 is removed, the lithium metal layer 430 is positioned between at least a portion of the seed layer 420 at one end of the anode film stack 465 and the receiving substrate 440 at the opposite end of the anode film stack 465. The seed layer 420 or a portion of the seed layer 420 positioned at the end of the anode film stack 465 can also function as a surface passivation layer for the lithium metal layer 430 positioned between the seed layer 420 and the receiving substrate 440. The surface passivation layer may include the seed layer 420 or certain sublayers of the seed layer 420.

[0069]

[0018] In operation 306, as described in operation 107 above and shown in Figure 2G, the anode film stack 465 can be integrated with a separator, an anode stack, or both a separator and a cathode stack to form an energy storage device.

[0070]

[0019] Figure 5 shows a schematic diagram of a transfer system 500 in a roll-to-roll tool for manufacturing an energy storage device according to the method of Figure 3, and is used in a roll-to-roll process using, for example, the laminate transfer system 700 shown in Figure 7. In one or more implementations, which can also be combined with other implementations, the laminate transfer process of operations 303 and 305 may include transferring lithium metal layers 530, 532 from separate SIDT stacks to both sides of a flexible receiving substrate 540. As described in operation 301, each SIDT stack is provided, each containing lithium metal layers 530, 532 and seed layers 520, 522, respectively, arranged on flexible support layers 510, 512.

[0071]

[0020] The transfer stem 500 comprises a first flexible carrier supply hub 515 and a second flexible carrier supply hub 525. The supply roll 511 for the flexible support layer 510 is positioned on the first flexible carrier supply hub 515. The supply roll 511 may include a lithium metal layer 530 and a seed layer 520 formed on the flexible support layer 510. The supply roll 521 for the flexible support layer 512 is positioned on the second flexible carrier supply hub 525. The supply roll 511 may include a lithium metal layer 532 and a seed layer 522 formed on the flexible support layer 512.

[0072]

[0021] The transfer system 500 also includes a flexible receiving substrate supply hub 535. The supply roll 531 of the flexible receiving substrate 540 is positioned on the flexible receiving substrate supply hub 535. The supply rolls 511 and 521 are transferred within the calendering unit 550 such that the lithium metal layer 530 on the flexible support layer 510 faces the upper surface 540U of the flexible receiving substrate 540, and the lithium metal layer 532 on the flexible support layer 512 faces the lower surface 540L of the flexible receiving substrate 540.

[0073]

[0022] The transfer system 500 further includes a calendering unit 550. The calendering device 550 includes one or more calendering rollers, for example, a first calendering roller 551 and a second calendering roller 582. The flexible support layer 510, the flexible support layer 512, and the flexible receiving substrate 540 are arranged to be transferred along a path extending through the calendering unit 550. When the flexible support layer 510, the flexible support layer 512, and the flexible substrate stack 1540 are transferred between the first calendering roller 551 and the second calendering roller 582, the flexible receiving substrate 540 is positioned between the flexible support layer 510 and the flexible support layer 512. The roller 551 for the first calender and the roller 582 for the second calender apply a large amount of pressure to the flexible support layers 510, 512 and the flexible receiving substrate 540, thereby transferring the SIDT stack on each of the flexible support layers 510, 512 to the flexible receiving substrate 540. In some implementations, the first and second calender rollers 551 and 582 may also be heated to facilitate the lamination and transfer of the lithium metal layers 530 and 532. Subsequently, tension is applied to the flexible support layers 510 and 512 by the first and second calender rollers 582 and 584, releasing the flexible support layers 510 and 512 from the flexible receiving substrate 540, thereby forming the film stack 560.

[0074]

[0023] The transfer stem 500 comprises a first flexible pickup hub 516 and a second flexible pickup hub 526. The pickup roll 512 of the flexible support layer 510 is positioned on the first flexible carrier pickup hub 516. The pickup roll 522 of the second flexible carrier 412 is positioned on the second flexible carrier pickup hub 526. When the flexible support layer 510 is wound onto the first flexible carrier pickup hub 516, the lithium metal layer 530 and seed layer 520 that were previously present on the first flexible carrier 110 are transferred to the flexible receiving substrate 540 by the calender rollers 551 and 582, so that the lithium metal layer 530 and seed layer 520 are no longer present on the flexible support layer 510. Similarly, when the flexible support layer 512 is wound onto the second flexible carrier pickup hub 526, the lithium metal layer 532 and seed layer 522 are no longer present on the flexible support layer 512 because the lithium metal layer 532 and seed layer 522 that were previously present on the flexible support layer 512 are also transferred to the flexible receiving substrate 540 by the calender rollers 551 and 582. In some implementations, the rollers 582 and 584 are configured as pickup hubs with corresponding pickup rollers to recover or reuse the flexible support layers 510 and 512.

[0075]

[0024] The transfer system 500 includes a flexible substrate stack pickup hub 570. A pickup roll 562 for the flexible receiving substrate 540 is positioned on the flexible substrate stack pickup hub 570. The flexible receiving substrate 540 includes a film stack 560 in which a lithium metal layer 530 is positioned between a seed layer 520 and the upper surface 540U of the flexible receiving substrate 540, and a lithium metal layer 532 is positioned between a seed layer 522 and the lower surface 540L of the flexible receiving substrate 540. The seed layers 520, 522 in the film stack 560 may function as surface passivation layers for the lithium metal layers 530, 532. The film stack 560 can then be transferred to the flexible substrate pickup roll 570.

[0076]

[0025] The transfer system 500 further includes a plurality of rollers 581-584. In some implementations, each of the rollers 581-584 may be a passive roller. The rollers 581-584 can help apply appropriate tension to the flexible support layers 510, 512 and the flexible receiving substrate 540 and change direction as they pass through different parts of the transfer system 500. Some of the rollers 581-584 also help move the flexible support layers 510, 512 closer to or further away from the flexible receiving substrate 540. For example, the first roller 581 can help bring the flexible support layers 510, 512 into contact with the flexible receiving substrate 540 before they pass through the calendering unit 550. Furthermore, the second and third calender rollers 582, 583 apply tension to the flexible support layers 510, 512, providing a position for releasing the flexible support layers 510, 512 from the flexible receiving substrate 540. In some implementations, one or more of the rollers 581-584 may be rods, such as metal rods, that can apply tension to the carrier or flexible substrate during the movement of the carrier or flexible substrate.

[0077]

[0026] The transfer system 500 may further include a housing 517 positioned around the internal region 508. The housing 517 can be used to maintain the environment within the internal region 508, separate from the environment surrounding the transfer system 500. For example, the internal region 508 may have different gas concentrations, different temperatures and / or pressures compared to the environment surrounding the transfer system 500.

[0078]

[0027] Figure 6 shows a schematic diagram of a flexible substrate coating apparatus 600 for forming at least a portion of an anode film stack as described according to one or more implementations of the present disclosure. The flexible substrate coating apparatus 600 may be a roll-to-roll coating system. The flexible substrate coating apparatus 600 can be used to perform some of the methods 100 and 300 described herein, which can be performed using vacuum deposition.

[0079]

[0028] The flexible substrate coating apparatus 600 may be Applied Materials' SMARTWEB® and is adapted to manufacture lithium anode devices according to the implementation described herein. According to some implementations, the flexible substrate coating apparatus 600 can be used to manufacture lithium anodes or pre-lithified anodes, in particular to manufacture portions of the SIDT stack 255 containing lithium films. The flexible substrate coating apparatus 600 is configured as a roll-to-roll system including an unwinding module 602, a processing module 604, and a winding module 606. In one or more implementations, the processing module 604 is configured by sequentially arranging a plurality of processing modules or processing chambers 610, 620, 630, and 640, each configured to perform one processing operation on a continuous sheet material 650 or a web-like material (e.g., a flexible support layer 210 or a flexible support layer stack 200). As shown in Figure 6, in one or more implementations, the processing chambers 610-640 are arranged radially around the coating drum 655. Other arrangements are also considered. For example, in another embodiment, the processing chambers may be arranged linearly.

[0080]

[0029] In one implementation, processing chambers 610 to 640 are independent modular processing chambers, and each modular processing chamber is structurally separated from the other modular processing chambers. Therefore, each independent modular processing chamber can be individually positioned, rearranged, replaced, or maintained without affecting each other. Although four processing chambers 610 to 640 are shown, it should be understood that any number of processing chambers may be included in the flexible substrate coating apparatus 600.

[0081]

[0030] The processing chambers 610-640 may include any suitable structures, configurations, arrangements, and / or components that enable the flexible substrate coating apparatus 600 to deposit portions of the SIDT stack by the implementation of the present disclosure. For example, the processing chambers may include, but are not limited to, a suitable deposition system such as a coating source, power supply, separate pressure control devices, deposition control system, and temperature control device. In a typical implementation, each chamber is provided with a separate gas supply device. The chambers are usually separated from each other to provide good gas separation. The flexible substrate coating apparatus 600 by the implementation described herein is not limited to the number of deposition chambers. For example, the flexible substrate coating apparatus 600 may include, but is not limited to, three, six, or twelve processing chambers.

[0082]

[0031] Processing chambers 610-640 typically include one or more deposition units 612, 622, 632, and 642. Generally, one or more deposition units described herein can be selected from the group consisting of CVD sources, ALD sources, PECVD sources, and PVD sources. One or more deposition units may include sputtering sources such as evaporation sources, magnetron sputtering sources, DC sputtering sources, AC sputtering sources, pulsed sputtering sources, radio frequency (RF) sputtering sources, or medium wave (MF) sputtering sources. One or more deposition units may include evaporation sources. In one implementation, the evaporation source is a thermal evaporation source or an electron beam evaporation source. In one implementation, the evaporation source is a lithium (Li) source. Furthermore, the evaporation source may also be an alloy of two or more metals. The material to be deposited (e.g., lithium) can be provided in a crucible. Lithium can be evaporated, for example, by thermal evaporation techniques or electron beam evaporation techniques.

[0083]

[0032] In some implementations, one or more of the chambers may be configured to perform deposition by other methods such as chemical vapor deposition, atomic layer deposition, or pulsed laser deposition, but are not limited to these. In some implementations, one or more of the chambers may be configured to perform plasma processing processes such as plasma oxidation or plasma nitriding processes.

[0084]

[0033] In one or more mountings, processing chambers 610-640 are configured to process both sides of a continuous sheet of material 650. The flexible substrate coating apparatus 600 is configured to process a horizontally oriented continuous sheet of material 650, but the flexible substrate coating apparatus 600 may be configured to process substrates positioned in different orientations, for example, the continuous sheet of material 650 may be vertically oriented. In one or more mountings, the continuous sheet of material 650 is a flexible support layer, for example, a flexible support layer stack 200 as described herein. In one or more mountings, the continuous sheet of material 650 includes a PET substrate and optionally a release layer.

[0085]

[0034] In one or more implementations, the flexible substrate coating apparatus 600 includes a transfer mechanism 652. The transfer mechanism 652 may include any transfer mechanism that can move a continuous sheet of material 650 through the processing areas of the processing chambers 610-640. The transfer mechanism 652 may include a common transport architecture. The common transport architecture may include a reel-to-reel system having a common take-up reel 654 positioned in a take-up module 606, a coating drum 655 positioned in the processing module 604, and a supply reel 656 positioned in an unwinding module 602. The take-up reel 654, the coating drum 655, and the supply reel 656 may be heated individually. The take-up reel 654, the coating drum 655, and the supply reel 656 may be heated individually using an internal or external heat source positioned within each reel. The common transport architecture may further comprise one or more auxiliary transport reels 653a, 653b positioned between the take-up reel 654, the coating drum 655, and the supply reel 656. Although the flexible substrate coating apparatus 600 is shown to have a single processing area, in one or more implementations it may be advantageous to have separate or isolated processing areas for each individual processing chamber 610-640. In the case of implementations with individual processing areas, modules, or chambers, the common transport architecture may be a reel-to-reel system with individual take-up reels and supply reels for each chamber or processing area, and one or more optional intermediate transport reels positioned between the take-up reels and supply reels.

[0086]

[0035] The flexible substrate coating apparatus 600 may include a feed reel 656 and a take-up reel 654 for moving a continuous sheet of material 650 through various processing chambers 610 to 640. In one or more mountings, which can also be combined with other mountings, each of the processing chambers may be configured to deposit a portion of the SIDT stack 255. In one mounting, the first processing chamber 610 and the second processing chamber 620 are each configured to deposit one or more of the seed layer 220, the protective layer, and / or the SEI layer. The third processing chamber 630 and the fourth processing chamber 640 are configured to deposit an alkali metal-containing film, for example, a portion of the lithium metal layer 250.

[0087]

[0036] In one implementation, processing chambers 630 and 640 are configured to deposit a thin film of lithium metal onto a continuous sheet 650 of material. Any suitable lithium deposition process for depositing a thin film of lithium metal may be used for depositing the lithium metal film. The deposition of the lithium metal film may be by a PVD process such as evaporation. The chamber for depositing the lithium metal film may include a PVD system such as an electron beam evaporator, a thermal evaporator, or a lamination system.

[0088]

[0037] During operation, the continuous sheet of material 650 is unwound from the supply reel 656 in accordance with the direction of movement of the substrate indicated by the arrow 608. The continuous sheet of material 650 is guided via one or more auxiliary transfer reels 653a, 653b. The continuous sheet of material 650 is also guided by one or more substrate guide control units (not shown) which can control the proper movement of the flexible substrate, for example, by fine-tuning the orientation of the flexible substrate.

[0089]

[0038] After being unwound from the supply reel 656 and passing through the auxiliary transfer reel 653a, the continuous sheet material 650 passes through the deposition areas (corresponding to the positions of deposition units 612, 622, 632, and 642) provided on the coating drum 655. During operation, the coating drum 655 rotates around the axis 651, and the flexible substrate moves in the direction of arrow 608.

[0090]

[0039] Figure 7 shows a schematic side view of a laminate transfer system 700 according to one or more embodiments of the present disclosure. The laminate transfer system 700 includes, for example, a SIDT stack 255 having a lithium metal layer on a flexible support layer 710 (e.g., a flexible support layer stack 200), and a device for transferring a second flexible support layer 720 (e.g., a flexible support layer stack 200) to both sides of a flexible receiving substrate 730 (e.g., a receiving substrate 260), thereby allowing the receiving substrate 260 having a lithium metal layer 250 to be used as an electrode (e.g., an anode) or a pre-lithified electrode of a lithium-ion battery. The laminate transfer system 700 may also include a preheating unit (not shown) for preheating the SIDT stack 255 on the flexible support layers 710, 720 before transferring it to the flexible receiving substrate 730. The laminate transfer system 700 may further include a calendering unit 740 for transferring the SIDT stack 255 on the flexible support layers 710, 720 to a flexible receiving substrate 730.

[0091]

[0040] The laminate transfer system 700 includes a first flexible support layer supply hub 715. A supply roll 711 of the first flexible support layer 710 is positioned on the first flexible support layer supply hub 715. In some implementations, the first flexible support layer 710 may be formed from a polymer material such as polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polyimide (PI), metallized plastic, or a combination thereof. A SIDT stack including a lithium metal layer (not shown in Figure 7) is positioned on the lower surface 710L of the first flexible support layer 710, so that this lithium metal layer faces the upper surface 730U of the flexible support layer 730 as the first flexible support layer 710 and the flexible receiving substrate 730 pass through the calendering unit 740. The upper surface 730U of the flexible receiving substrate 730 is opposite to the lower surface 730L of the flexible receiving substrate 730. The upper surface 730U is also referred to as the first surface or first side surface of the flexible receiving substrate 730, while the lower surface is also referred to as the second surface or second side surface of the flexible receiving substrate 730.

[0092]

[0041] The laminate transfer system 700 includes a second flexible support layer supply hub 725. A supply roll 721 for the second flexible support layer 720 is positioned on the second flexible support layer supply hub 725. In some implementations, the second flexible support layer 720 may be formed from the same material as the first flexible support layer 710 (e.g., PET). For example, a SIDT stack including a lithium metal layer (not shown in Figure 7) is positioned on the upper side 720U of the second flexible support layer 720, so that this lithium metal layer faces the lower surface 730L of the flexible receiving substrate 730 as the second flexible support layer 720 and the flexible receiving substrate 730 are transported through the calendering unit 740.

[0093]

[0042] The laminate transfer system 700 includes a flexible substrate supply hub 735. A feed roll 731 of the flexible receiving substrate 730 is positioned on the flexible substrate supply hub 735. In some implementations, the flexible receiving substrate 730 may be formed from one or more of the following materials: copper, graphite, silicon, silicon graphite, silicon oxide graphite, silicon, metallized plastic, or other materials.

[0094]

[0043] The laminate transfer system 700 further includes a calendering unit 740. The calendering unit 740 includes a roller 741 for a first calender and a roller 742 for a second calender. The first flexible support layer 710, the second flexible support layer 720, and the flexible receiving substrate 730 are configured to be transported along a path extending between the first calendering roller 741 and the second calendering roller 742. As the first flexible support layer 710, the second flexible support layer 720, and the flexible receiving substrate 730 are transported between the first calendering roller 741 and the second calendering roller 742, the flexible receiving substrate 730 is positioned between the first flexible support layer 710 and the second flexible support layer 720. The calender rollers 741 and 742 apply high pressure to the flexible support layers 710 and 720 and the flexible receiving substrate 730, transferring the SIDT stack 255, which includes at least a portion of the lithium metal layer 250 and seed layer 220 formed on the flexible support layers 710 and 720 respectively, to the flexible receiving substrate 730.

[0095]

[0044] The laminate transfer system 700 includes a first flexible support layer pickup hub 716. The pickup roll 712 of the first flexible support layer 710 is positioned on the first flexible support layer pickup hub 716. By the time the first flexible support layer 710 is wound onto the first flexible support layer pickup hub 716, the SIDT stack 255 is no longer present on the first flexible support layer 710. This is because the SIDT stack 255 that was previously present on the first flexible support layer 710 is transferred onto the flexible receiving substrate 730 by the calendering unit 740.

[0096]

[0045] The laminate transfer system 700 includes a second flexible support layer pickup hub 726. The pickup roll 722 of the second flexible support layer 720 is positioned on the second flexible support layer pickup hub 726. As the second flexible support layer 720 is wound onto the second flexible support layer pickup hub 726, the SIDT stack 255 is no longer present on the second flexible support layer 720. This is because the SIDT stack 255 that was previously present on the second flexible support layer 720 is transferred onto the flexible receiving substrate 730 by the calendering unit 740.

[0097]

[0046] The laminate transfer system 700 includes a flexible substrate pickup hub 736. The pickup roll 732 of the flexible receiving substrate 730 is positioned on the flexible substrate pickup hub 736. The flexible receiving substrate 730 has SIDT stacks on its upper surface 730U and lower surface 730L, respectively. The SIDT stacks are transferred from the respective flexible support layers 710, 720 to the flexible receiving substrate 730 by the calendering unit 740.

[0098]

[0047] The laminate transfer system 700 further includes a plurality of rollers 781-788. In some implementations, each of the rollers 781-788 may be a passive roller. The rollers 781-788 can help apply appropriate tension to the flexible support layers 710, 720 and the flexible receiving substrate 730 and change their orientation as they pass through different parts of the transfer system 700. Some of the rollers 781-788 also help move the flexible support layers 710, 720 closer to or further away from the flexible receiving substrate 730. For example, second and third rollers 782, 783 help bring the flexible support layers 710, 720 into contact with the flexible receiving substrate 730 before they pass through the calendering unit 740. Furthermore, the fourth and fifth rollers 784, 785 apply tension to the flexible support layers 710, 720, providing a position for releasing the flexible support layers 710, 720 from the flexible receiving substrate 730. Once the flexible support layers 710, 720 are separated from the flexible receiving substrate 730, the sixth and seventh rollers 786, 787 sequentially transport the flexible support layers 710, 720 to the corresponding flexible support layer pickup hubs 716, 726, which can then be used to recover or reuse the flexible support layers 710, 720. In some implementations, one or more of the rollers 781-788 may instead be rods, such as metal rods, that can apply tension during the movement of the flexible support layers or flexible substrates.

[0099]

[0048] The laminate transfer system 700 may further include actuators (not shown) configured to rotate each hub 715, 716, 725, 726, 735, 736, thereby transporting the flexible support layers 710, 720 and the flexible receiving substrate 730 from the corresponding supply hubs 715, 725, 735 through the calendering unit 740 to the corresponding pickup hubs 716, 726, 736. The laminate transfer system 700 may further include one or more actuators (not shown) for rotating the calendering rollers 741, 742 of the calendering unit 740. The rotational speed of the actuators can be adjusted to control the speed at which the flexible receiving substrate 730 and the flexible support layers 710, 720 are transported through the laminate transfer system 700.

[0100]

[0049] In the laminate transfer system 700, the flexible receiving substrate 730 is transported from the supply roll 731 supported by the supply hub 735, through the first roller 781, through the second and third rollers 782, 783, through the calender rollers 741, 742, through the fourth and fifth rollers 784, 785, through the eighth roller 788, to the pickup roll 732 around the pickup hub 736. The pickup hub 736 is configured to rotate after the flexible receiving substrate 730 has passed between the first calender roller 741 and the second calender roller 742 to assist in transporting the flexible substrate along the path. Similarly, the pickup hubs 716, 726 are configured to rotate to assist in transporting the flexible support layers along the path between the first and second supply hubs 715, 725 and the first and second support layer pickup hubs 716, 726.

[0101]

[0050] The stack transfer system 700 may also include a controller 705 for controlling the processes performed by the stack transfer system 700. The controller 705 can be any type of controller used in industrial settings, such as a programmable logic control unit (PLC). The controller 705 includes a processor 707, memory 706, and input / output (I / O) circuitry 708. The controller 705 may further include one or more of the following components (not shown), such as one or more power supplies, a clock, communication components (e.g., a network interface card), and a user interface commonly found in controllers for semiconductor devices.

[0102]

[0051] Memory 706 may include non-temporary memory. Non-temporary memory can be used to store programs and settings, which will be described later. Memory 706 may include one or more readily available types of memory, such as read-only memory (ROM) (e.g., electrically erasable programmable read-only memory (EEPROM), flash memory, floppy disk, hard disk) or random access memory (RAM) (e.g., non-volatile random access memory (NVRAM)).

[0103]

[0052] The processor 707 is configured to execute various programs stored in the memory 706, such as programs configured to perform the methods 100 and 300 described herein. While these programs are running, the controller 705 can communicate with input / output devices via the input / output circuit 708. For example, while these programs are running and communicating via the I / O circuit 708, the controller 705 can control outputs (e.g., actuators connected to different hubs or calendar units 740). The memory 706 may further include various operating settings used to control the stack transfer system 700. For example, setting items may include speed settings for actuators connected to hubs.

[0104]

[0053] In summary, the present disclosure provides a method for transferring a lithium metal layer using a seed layer formed on a flexible support layer as a release layer for transfer to a receiving substrate. By using a seed layer, the thickness, chemical composition, quality, and peeling pressure of the release layer required to separate the lithium metal layer from the flexible support layer can be controlled. When separating the lithium metal layer from the flexible support layer, at least a portion of the seed layer is transferred to the receiving substrate and acts as a surface passivation layer for the lithium metal layer transferred to the receiving substrate. Thus, by using a seed layer, a simple, effective, and controllable method can be obtained for achieving a high-performance lithium transfer process for the formation of anode film stacks and pre-lithiation. The formed anode film stack can function as an anode structure for an energy storage device. The seed layer described herein not only functions as a surface passivation layer for the transferred lithium metal layer, but also controls the impedance between the formed anode structure and the separator interface to, for example, about 200 ohms / cm². 2 It can be configured and designed to maintain a low value, such as less than [value missing]. The seed layer material can be adjusted and selected with cost efficiency in mind, and the chemical composition of the flexible support layer, and / or the specific battery chemical composition and application in which the lithium metal layer is used can also be taken into consideration.

[0105]

[0054] The above describes embodiments of the present disclosure, but other further embodiments can be devised without departing from the basic scope of the present disclosure, the scope of which will be defined by the claims described below.

Claims

1. A method for transferring a lithium metal layer, Forming a seed layer on top of a flexible support layer, Depositing a lithium metal layer on a seed layer, Laminating lithium metal layers onto a flexible receiving substrate, In order to transfer the lithium metal layer to the receiving substrate, the lithium metal layer is separated from the flexible support layer. A method comprising transferring at least a portion of the seed layer together with the lithium metal layer to a receiving substrate, thereby bringing about passivation of the lithium metal layer.

2. The method according to claim 1, wherein the seed layer is formed on the flexible support layer by sputtering, reactive sputtering, evaporation, PVD, CVD, PECVD, or other vapor-phase deposition processes.

3. The method according to claim 1, wherein both the seed layer and the lithium metal layer are formed in a vacuum environment without breaking the vacuum.

4. The method according to claim 1, wherein the flexible support layer comprises polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polyimide (PI), poly(methyl methacrylate) (PMMA), cellulose triacetate (TAC), polypropylene (PP), polyethylene (PE), polycarbonate (PC), multilayers thereof, or combinations thereof.

5. The method according to claim 1, wherein the seed layer comprises LiF, Li2CO3, Ag, Bi, Sn, Ag+LiF, Bi+LiF, Sn+LiF, AgF, CxFy, or a combination thereof.

6. The method according to claim 1, wherein the seed layer has a thickness between approximately 1 nm and approximately 5,000 nm.

7. The method according to claim 1, wherein the portion of the seed layer transferred to the receiving substrate functions as a surface passivation layer for the lithium metal layer.

8. The method according to claim 1, wherein transferring the lithium metal layer includes applying a peeling pressure between about 0.3 gram force / cm² and about 16 gram force / cm² to separate the flexible support layer from the lithium metal layer.

9. The method according to claim 1, wherein the seed layer comprises a plurality of sublayers, and transferring the lithium metal layer from the flexible support layer includes separating the sublayers of the seed layer.

10. The method according to claim 1, wherein the receiving substrate comprises one or more current collectors made from aluminum (Al), copper (Cu), zinc (Zn), nickel (Ni), cobalt (Co), manganese (Mn), chromium (Cr), stainless steel, clad materials, alloys thereof, or combinations thereof.

11. A method for forming a membrane stack for an energy storage device, Placing a flexible support layer in a vacuum environment, This involves forming a seed layer on top of a flexible support layer, and the seed layer is made of LiF, Li ２ CO ３ Forming a seed layer containing Ag, Bi, Sn, Ag+LiF, Bi+LiF, Sn+LiF, AgF, CxFy, or combinations thereof, The method involves depositing a lithium metal layer on a seed layer, the seed layer being for releasing the lithium metal layer from a flexible support layer, and depositing a lithium metal layer. The method involves laminating a lithium metal layer onto a flexible receiving substrate, wherein the flexible receiving substrate includes one or more current collectors made from aluminum (Al), copper (Cu), zinc (Zn), nickel (Ni), cobalt (Co), manganese (Mn), chromium (Cr), stainless steel, clad materials, alloys thereof, or combinations thereof, and the lithium metal layer is laminated onto the substrate. The process involves transferring a lithium metal layer from a flexible support layer to a flexible receiving substrate in order to form a film stack, wherein at least a portion of the seed layer is transferred to the flexible receiving substrate together with the lithium metal layer. A method that includes this.

12. The method according to claim 11, wherein the flexible support layer comprises polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polyimide (PI), poly(methyl methacrylate) (PMMA), cellulose triacetate (TAC), polypropylene (PP), polyethylene (PE), polycarbonate (PC), multilayers thereof, or combinations thereof.

13. The method according to claim 11, wherein the seed layer has a thickness between approximately 1 nm and approximately 5,000 nm.

14. The method according to claim 11, further comprising preheating the lithium layer and seed layer on a flexible support layer to a temperature between approximately 30 degrees Celsius and approximately 200 degrees Celsius before laminating the lithium metal layer onto a flexible receiving substrate.

15. A membrane stack for an energy storage device, A flexible receiving substrate, A lithium metal layer placed on a flexible receiving substrate, A seed layer disposed on at least a portion of a lithium metal layer, the seed layer being intended to provide passivation to the portion of the lithium metal layer present between the seed layer and a flexible receiving substrate, including a seed layer A film stack comprising a lithium metal layer and a seed layer, wherein the seed layer acts as a release layer to separate the lithium metal layer from the flexible support layer, and the layer is transferred from the flexible support layer to a flexible receiving substrate.

16. The seed layer is LiF, Li ２ CO ３ The membrane stack according to claim 20, comprising Ag, Bi, Sn, Ag+LiF, Bi+LiF, Sn+LiF, AgF, CxFy, or a combination thereof.

17. The film stack according to claim 15, wherein the seed layer has a thickness between approximately 1 nm and approximately 5,000 nm.

18. The film stack according to claim 15, wherein the seed layer functions as a surface passivation layer for the lithium metal layer.

19. The membrane stack according to claim 15, wherein the impedance of the membrane stack is less than about 200 ohms / cm².

20. The film stack according to claim 15, wherein the flexible receiving substrate comprises one or more current collectors made from aluminum (Al), copper (Cu), zinc (Zn), nickel (Ni), cobalt (Co), manganese (Mn), chromium (Cr), stainless steel, clad materials, alloys thereof, or combinations thereof.

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