Fabrication tool architecture for lithium transfer by lift-off process

Abstract

A flexible substrate processing system is provided. The flexible substrate processing system includes: a first supply hub for supplying a flexible carrier film on which an alkali metal film is formed; a second supply hub for supplying a flexible substrate film stack; a first pickup hub for collecting the flexible carrier film after the alkali metal film is transferred to the flexible substrate film stack; a second pickup hub for collecting the flexible substrate film stack on which the alkali metal film is formed; and a laser lift-off unit positioned downstream of the first supply hub and the second supply hub and upstream of the first pick-up hub and the second pick-up hub. The laser lift-off unit comprises: a laser source configured to generate laser energy, the laser energy being directed toward a first surface of the flexible carrier film; and an optical scanner configured to direct the laser energy toward the first surface of the flexible carrier film.

Description

Technical Field

[0001] This disclosure generally relates to an alkali metal energy storage device and a method for manufacturing the alkali metal energy storage device. More specifically, this disclosure relates to a device stack including patterned alkali metal electrodes and a method for manufacturing the device stack. Background Technology

[0002] Rechargeable electrochemical energy storage systems are becoming increasingly important in many areas of daily life. High-capacity electrochemical energy storage devices, such as lithium-ion (Li-ion) batteries, are being used in a growing number of applications, including portable electronics, medical, transportation, grid-connected large-scale energy storage, renewable energy storage, and uninterruptible power supplies (UPS). Traditional lead / sulfuric acid batteries often lack capacity and are often inadequate in terms of cycle life for these growing applications. However, lithium-ion batteries are considered to offer the best solution.

[0003] Therefore, there is an increasing need for methods and systems for the deposition and treatment of alkali metals used in energy storage devices. Summary of the Invention

[0004] This disclosure generally relates to an alkali metal-containing device and a method for manufacturing such a device. More specifically, this disclosure relates to a device stack including a lithium metal anode and a pre-lithiated anode for energy storage devices, and a method for manufacturing the same.

[0005] In one aspect, a flexible substrate processing system is provided. The flexible substrate processing system includes: a first supply hub for supplying a flexible carrier film on which an alkali metal film is formed; a second supply hub for supplying a stack of flexible substrate films; a first pick-up hub for collecting the flexible carrier film after the alkali metal film has been transferred to the flexible substrate film stack; a second pick-up hub for collecting the flexible substrate film stack on which the alkali metal film is formed; and a laser lift-off unit positioned downstream of the first and second supply hubs and upstream of the first and second pick-up hubs. The laser lift-off unit includes: a laser source configured to generate laser energy directed toward a first surface of the flexible carrier film; and an optical scanner configured to direct the laser energy toward the first surface of the flexible carrier film.

[0006] The implementation may include one or more of the following. The flexible substrate processing system further includes: a pair of rollers positioned downstream of a first and second supply hub and upstream of a laser source, the pair of rollers being configured to contact an alkali metal film with a flexible substrate film stack. The pair of rollers includes at least one pinch roller. The pair of rollers includes at least one calendering roller. The laser source is selected from infrared (IR) fiber lasers, ultraviolet (UV) lasers, or green lasers. The optical scanner is a single- or multi-axis large-angle galvanometer optical scanner. The optical scanner is a polygon scanner, an electro-optic scanner, an acousto-optic device, or a combination thereof. The flexible substrate processing system further includes: a passivation unit positioned downstream of a laser stripping unit and upstream of a second pick-up hub, the passivation unit being positioned to passivate the alkali metal film formed on the flexible substrate film stack. The flexible substrate processing system further includes: an in-line slitting assembly including blades for slitting the flexible carrier film, the in-line slitting assembly being positioned downstream of the laser stripping unit and upstream of the first pick-up hub.

[0007] In another aspect, a flexible substrate processing system for forming an energy storage device is provided. The flexible substrate processing system includes a laser lift-off unit. The laser lift-off unit includes: a laser source configured to generate laser energy directed toward a first surface of a flexible carrier film; and an optical scanner configured to direct the laser energy toward the first surface of the flexible carrier film. The flexible substrate processing system further includes a system controller. The system controller is configured to cause the laser lift-off unit to perform a process including: transporting a flexible carrier film stack, comprising a flexible carrier film on which an alkali metal film is formed, from a supply hub toward a pick-up hub; contacting the flexible carrier film stack with a flexible substrate film stack, wherein the alkali metal film contacts the flexible substrate film stack; exposing the first surface of the flexible carrier film stack to laser energy to separate the flexible carrier film from the alkali metal film; and removing the flexible carrier film from the flexible substrate film stack.

[0008] The implementation may include one or more of the following: The laser source is selected from infrared (IR) fiber lasers, ultraviolet (UV) lasers, or green lasers. The optical scanner is a single- or multi-axis large-angle galvanometer optical scanner. The flexible substrate processing system further includes: a pair of rollers positioned upstream of the laser source, the pair of rollers bringing the flexible carrier film stack into contact with the flexible substrate film stack. The pair of rollers includes at least one clamping roller. The pair of rollers includes at least one calendering roller.

[0009] In another aspect, a method for forming a membrane stack for an energy storage device is provided. The method includes: transporting a flexible carrier membrane stack, including a flexible carrier membrane on which an alkali metal film is formed, from a supply hub toward a pick-up hub; contacting the flexible carrier membrane stack with a flexible substrate membrane stack, wherein the alkali metal film contacts the flexible substrate membrane stack; exposing a first surface of the flexible carrier membrane stack to laser energy to separate the flexible carrier membrane from the alkali metal film; and removing the flexible carrier membrane from the flexible substrate membrane stack.

[0010] The implementation may include one or more of the following: Exposing a first surface of the flexible carrier film stack to laser energy to separate the flexible carrier film from the alkali metal film includes patterning the alkali metal film by partially exposing a portion of the alkali metal film to laser energy. The laser energy is directed through the back side of the flexible carrier film. Exposing the first surface of the flexible carrier film stack to laser energy creates a void volume between the alkali metal film and the flexible carrier film stack. The flexible carrier film stack further includes a release layer disposed between the flexible carrier film and the alkali metal film, the release layer being capable of photoinduced depolymerization.

[0011] On the other hand, there are non-transitory computer-readable medium storage instructions that, when executed by the processor, cause the process to perform the operations of the aforementioned apparatus and / or methods. Attached Figure Description

[0012] To gain a more detailed understanding of the features described above in this disclosure, reference can be made to the implementations briefly outlined above, some of which are illustrated in the accompanying drawings. However, it should be noted that the drawings illustrate only typical implementations of this disclosure and should therefore not be construed as limiting the scope of this disclosure, as other equally effective embodiments are permissible.

[0013] Figure 1 A schematic side view illustrates an example of a flexible substrate transfer system incorporating a laser lift-off unit according to one or more implementations of this disclosure.

[0014] Figure 2 A schematic side view illustrating an example of a laser ablation unit according to one or more implementations of this disclosure is shown.

[0015] Figure 3 A schematic side view illustrates another example of a flexible substrate transfer system incorporating a laser lift-off unit according to one or more implementations of this disclosure.

[0016] Figure 4 A schematic side view illustrates yet another example of a flexible substrate transfer system incorporating a laser lift-off unit according to one or more implementations of this disclosure.

[0017] Figure 5 A schematic side view illustrates yet another example of a flexible substrate transfer system incorporating a laser lift-off unit according to one or more implementations of this disclosure.

[0018] Figure 6 A flowchart illustrating selected operations of a method for forming an energy storage device via a laser ablation process, according to one or more implementations of this disclosure, is provided.

[0019] Figures 7A-7D Examples of one or more implementations of this disclosure are illustrated. Figure 6 The method of manufacturing energy storage devices provides a view of various stages.

[0020] Figure 8 A flowchart illustrating selected operations of another method for forming an energy storage device via a laser ablation process, according to one or more implementations of this disclosure, is provided.

[0021] Figure 9 A flowchart illustrating selected operations of another method for forming an energy storage device via a laser ablation process, according to one or more implementations of this disclosure, is provided.

[0022] Figure 10 A schematic diagram illustrating a flash assembly according to one or more implementations of this disclosure is shown.

[0023] For ease of understanding, common elements across the figures have been indicated using the same element symbols where possible. It is envisioned that elements and features of one implementation can be beneficially incorporated into other implementations without further description. Detailed Implementation

[0024] This disclosure generally relates to alkali metal energy storage devices and methods for manufacturing alkali metal energy storage devices. More specifically, this disclosure relates to patterned alkali metal electrodes and methods for manufacturing such patterned alkali metal electrodes.

[0025] Substrate Independent Direct Transfer (SIDT) is a method of forming an electrode device stack by transferring one or more layers, including an alkali metal layer (e.g., a lithium metal layer), to a substrate stack (e.g., a current collector), in an implementation where lithium metal is used as the anode, or in an implementation for pre-lithiation of anode material already formed on the current collector. Alkali metals or alloys include alkali metals such as lithium metal, sodium, potassium, rubidium, cesium, francium, and alloys or combinations thereof. The formed anode material may include, or may be, but is not limited to, graphite, silicon, graphite silica, graphite silica, silicon, tin, hard carbon, metal oxides, or combinations thereof. The current collector may include, or may be, metallized plastic, copper, or combinations thereof. In the SIDT process, the alkali metal is formed over a flexible support layer stack made of one or more materials, such as a polymer substrate, e.g., polyethylene terephthalate (PET), paper, or combinations thereof. The material formed on the flexible support layer stack is directly transferred to the substrate stack. The substrate stack may include or may be a current collector, a current collector having an anode material formed thereon, a metallized plastic substrate, a separator layer, or a metallized plastic substrate having an alkali metal formed thereon. If a release layer is present, it is formed between the alkali metal layer and the flexible support layer stack, allowing the alkali metal and other materials to detach from the support layer stack and transfer to the current collector or anode material (if already present). The release layer may be selected from fluorocarbons, silicones, latexes, AlO₂, etc. x One or more of LiF, AlOOH, Ag, AgF, Bi, Zn, Mg, Sn, or metal halides.

[0026] However, transferring the lithium metal layer from the flexible support layer stack to the current collector or anode material presents several challenges. For example, after SIDT, trace amounts of material, such as a release layer, remain on the surface of the alkali metal layer of the formed film stack. Such release layer materials are often incompatible with end uses such as electrochemical devices because they can impede ion or electron transport. That is, the chemistry of the release layer may be incompatible with the final device, such as an energy storage device. For example, undesirable reactions of the release layer with gases (such as H2O, O2, N2, etc.) during handling, transportation, and subsequent integration can affect device integration. Therefore, SIDT is not used in the battery and capacitor industries, as these industries require high-quality alkali metal films suitable for device integration.

[0027] In one or more implementations that can be combined with other implementations, a system and method are provided for patterning alkali metals transferred onto a substrate stack using a laser lift-off (LLO) process. The substrate stack may be or include a current collector substrate, such as a copper substrate or a metallized plastic substrate, and optionally includes an anode material, such as silicon graphite, SiO2, etc. x-Gr or graphite, one or more of these. The LLO process is performed using an energy source generally suitable for delivering electromagnetic energy to a target area of ​​the substrate stack. The energy source for delivering electromagnetic energy may include an optical radiation source, such as a laser source or a flash lamp. Suitable laser sources include, but are not limited to, IR fiber lasers, UV lasers, or green lasers. Suitable flash lamp sources include, for example, xenon or krypton flash lamps, which can be used as an alternative to or in conjunction with a laser source. Without being bound by theory, but believed to be, the energy source activates the interface between the alkali metal film and the flexible carrier film, such as a PET-Li interface, from the flexible carrier film side and transfers the patterned alkali metal onto the substrate stack. The alkali metal at the activated flexible carrier film-alkali metal interface may subsequently be released from the flexible carrier film during removal of the flexible carrier film.

[0028] In one or more implementations that can be combined with other implementations, the described laser lift-off process can be incorporated into a roll-to-roll tool and used in a roll-to-roll process. The laser lift-off process transfers patterned alkali metal from the plastic carrier substrate to the roll-to-roll battery anode substrate by exposing the interface between the alkali metal layer and the plastic carrier substrate, such as a Li-PET interface, to a laser that induces alkali metal transfer at the interface. This interface between the alkali metal layer and the flexible carrier film may also include a release layer as described.

[0029] In one or more implementations that can be combined with other methods, laser lift-off processing enables the patterning of alkali metals. The alkali metal film can be patterned to match the pattern of material (e.g., anodic material) already deposited in a channel coating or skip coating process. In some implementations, the patterned alkali metal can be directly transferred onto the current collector substrate. Any suitable pattern, such as squares, triangles, or circles, can be achieved.

[0030] In one or more implementations that can be combined with other implementations, the laser lift-off process uses a laser source to generate an interfacial reaction with the release layer, interface layer, or both the release layer and interface layer between the alkali metal layer and the flexible carrier film (e.g., PET film) to enable subsequent removal of the flexible carrier film from the alkali metal layer at the activated interface.

[0031] In one or more implementations that can be combined with other implementations, a flexible carrier film stack is provided. The flexible carrier film stack may include a plastic substrate, such as a PET substrate. The flexible carrier film stack may further include a release layer formed on the flexible carrier film stack, such as a silicone or other deposited release layer. An alkali metal layer, such as a lithium metal layer, is formed above the flexible carrier film stack. In some implementations where no release layer is present, the alkali metal layer may be formed directly on the plastic substrate. In implementations where a release layer is present, the alkali metal layer may be formed directly on the release layer. The flexible carrier film stack with the alkali metal layer formed thereon is exposed to a laser lift-off process. In one or more implementations, during the laser lift-off process, a laser is directed through the flexible carrier film stack to activate the interface between the alkali metal layer and the flexible carrier film stack, such as a Li-PET interface. The laser may be directed through the back side of the flexible carrier film stack, for example from the plastic substrate or PET side. Exposure to the laser can trigger an alkali metal transfer process, thereby creating a void volume between the alkali metal layer and the flexible carrier film stack. This void volume facilitates the separation of the alkali metal layer from the flexible carrier film stack during transfer from the alkali metal layer to the current collector substrate. Furthermore, precise laser beam positioning control enables the selective transfer of the alkali metal from the flexible carrier film stack to the substrate stack in a desired shape, forming electrode device stacks with various shapes. Additionally, laser exposure can be used to pattern the alkali metal layer, allowing precise alkali metal patterns to be transferred from the flexible carrier film stack to the substrate stack to form an anode device stack. Cathode structures and / or separators can be integrated with the formed anode device stack to form an energy storage device.

[0032] In one or more implementations that can be combined with other implementations, an IR fiber laser is used for the laser lift-off process. The laser lift-off process may include laser activation and lift-off using a PET substrate having an alkali metal layer (e.g., a 20 μm lithium layer) and a silicone release layer. In one example, the IR fiber laser is a 1060 nm laser with a pulse width of 5 to 500 nanoseconds, such as a 30 nanosecond pulse width, a Gaussian distribution, a spot size of approximately 150 μm, a grating velocity of 2 m / sec, and a line spacing of 70 μm.

[0033] The selection of laser parameters, such as pulse width, is crucial for developing a successful laser lift-off process that achieves clean patterning while minimizing damage to the underlying substrate during the process. High-frequency nanosecond pulsed IR lasers or picosecond pulsed IR lasers can be used based on specific laser-material interactions for lithium material stacks. Lithium is unique in that its melting temperature is only 453.65 K (180.50 °C), while its boiling temperature is still very high at 1603 K (1330 °C). In comparison, PET has a melting temperature of 523 K (250 °C) and a boiling temperature of 623 K (350 °C). For conductive substrates such as copper, the absorption of IR lasers is much lower than that of green (approximately 520 to 540 nm) or UV lasers (<360 nm). For example, at ambient temperature, the optical absorption of a 1064 nm laser in copper is less than 5%, while the optical absorption of a 532 nm green laser in copper is approximately 40%. A 1064 nm laser in molten copper still exhibits approximately 5% optical absorption. From the perspective of avoiding copper damage, a 1 μm IR laser wavelength is more advantageous than green or UV laser wavelengths. Furthermore, at the same average power level and using the same type of laser, IR lasers are more reliable and cost-effective.

[0034] IR nanosecond lasers with pulse durations less than 30 nanoseconds and an infrared wavelength of only 1064 nanometers are suitable for LLO processes. However, ultrashort pulse lasers can be used for purposes such as quality improvement. Lasers with longer pulse durations generate higher-density plasmas, resulting in greater gas pressure to release the interface between the PET carrier film and the lithium film. However, pulse durations longer than 50 nanoseconds require much higher pulse energy (or laser power) due to their low peak power. Conversely, shorter pulse durations allow for more precise processing, resulting in cleaner lithium edges.

[0035] Laser parameters can be selected to offer benefits such as providing sufficiently high laser intensity to pattern lithium while minimizing damage to the underlying substrate. Furthermore, parameters can be selected to provide meaningful process throughput for industrial applications while precisely controlling the ablation width (e.g., kerf width) and depth. As described, ultrashort pulse (USP) lasers (e.g., lasers with pulse durations in the femtosecond range), such as femtosecond or picosecond pulsed lasers, are suitable for providing these advantages. Such pulse widths for USPs can range from 5 femtoseconds to 999 femtoseconds, preferably 10 femtoseconds to 999 femtoseconds for femtosecond pulsed lasers and preferably 1 picosecond to 10 picoseconds for picosecond pulsed lasers. With USPs, shorter pulse widths result in higher peak power and less thermal effect, which increases control over the removal rate. For example, a 10 femtosecond pulse with the same pulse energy has 1000 times higher peak power than a 10 picosecond pulse. Therefore, the wavelength range is less critical because patterning can stop at a precise depth without thermally damaging the underlying substrate.

[0036] However, nanosecond pulsed laser stripping is also suitable because pulses longer than tens of picoseconds will begin to exhibit more significant thermal effects. Nanosecond pulsed lasers are also more cost-effective, although certain wavelengths offer better performance than others. For PET substrates, wavelength ranges of approximately 450 nm to approximately 1600 nm or approximately 450 nm to approximately 1550 nm will facilitate laser stripping of lithium using nanosecond pulses, resulting in highly transparent PET films. Wavelengths less than 450 nm or less than 355 nm can lead to scribing or cutting of PET substrates. For PI substrates, wavelengths in the range of approximately 700 nm to approximately 1700 nm or approximately 750 nm to approximately 1600 nm will provide laser stripping of lithium using nanosecond pulses. Similarly, wavelengths less than 450 nm can be used to scribing or cutting PI substrates.

[0037] Nanosecond pulses can range from about 1 ns to about 200 ns, or from about 1 ns to about 50 ns, or from about 1 ns to about 10 ns. For example, in one implementation, a nanosecond pulsed laser process with a wavelength closer to or in the IR range provides a cleaner patterning process than a nanosecond pulsed laser process with a wavelength closer to or in the UV range. In one or more implementations, a femtosecond pulsed laser process suitable for LLO processes is based on a laser with a wavelength approximately greater than or equal to 1 micrometer. In a particular implementation, pulses of approximately less than or equal to 15 nanoseconds are used with a laser with a wavelength approximately greater than or equal to 1 micrometer. However, in alternative implementations, dual laser wavelengths (e.g., a combination of an IR laser and a UV laser) can be used.

[0038] It should be noted that while some of the implementations described herein are not limited to any particular substrate on which they can be practiced, it is particularly advantageous to practice these implementations on flexible substrates, including, for example, roll-based substrates, panels, and discrete sheets. Flexible substrates can also be in the form of foils, polymer films, or sheets.

[0039] It should also be noted that the flexible substrate, film, or roll used in the implementations described herein is typically characterized by its bendability. The term "roll" may be used synonymously with the terms "strip," "flexible film," "flexible substrate," or "flexible conductive substrate." For example, the roll described in the implementations herein may be a polymer material.

[0040] It should be noted further that the described methods and systems can be used to form single-sided electrode structures and double-sided electrode structures.

[0041] Figure 1 A schematic diagram of a flexible substrate transfer system 100 incorporating a laser lift-off unit 200, according to one or more implementations of this disclosure, is illustrated. The transfer system 100 includes means for transferring an alkali metal film from a first flexible carrier film 110 and a second flexible carrier film 120 to each side of a flexible substrate stack 130, such that the flexible substrate stack 130 having the alkali metal film can be used as an electrode (e.g., an anode) in an energy storage device (e.g., a lithium-ion battery). The transfer system 100 includes a laser lift-off unit 200 for transferring the alkali metal film from the flexible carrier films 110, 120 to the flexible substrate stack 130. The transfer system 100 may further include a passivation unit 190 for passivating the newly exposed surfaces of the alkali metal film transferred to the flexible substrate stack 130. Components of the transfer system 100 may be positioned within a housing 102 or a chamber body.

[0042] The transfer system 100 includes a first flexible carrier supply hub 115. A supply roll 111 of a first flexible carrier film 110 is positioned on the first flexible carrier supply hub 115. In some implementations, the first flexible carrier film 110 may be formed of a polymeric material. Suitable polymeric materials include those that are transparent to laser light and have low or no photon absorption to prevent overheating and fire incidents. Examples of suitable polymeric materials include polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polyimide (PI), polymethyl methacrylate (PMMA), cellulose triacetate (TAC), polypropylene (PP), polyethylene (PE), polycarbonate (PC), biodegradable polymers such as polyethylene 2,5-furandicarboxylate (PEF), multilayers thereof, or combinations thereof. An alkali metal film is positioned on the lower surface 110L of the first flexible carrier film 110, such that when the first flexible carrier film 110 and the flexible substrate stack 130 are transported through the laser lift-off unit 200, the alkali metal film faces the upper surface 130U of the flexible substrate stack 130. The alkali metal film... Figure 2 The image shows an alkali metal film 241 after contact with the flexible substrate stack 130 during a laser lift-off process. The upper surface 130U of the flexible substrate stack 130 is located on the opposite side to the lower surface 130L of the flexible substrate stack 130. The upper surface 130U is also referred to as the first surface or first side of the flexible substrate stack 130, while the lower surface is also referred to as the second surface or second side of the flexible substrate stack 130.

[0043] The transfer system 100 includes a second flexible carrier supply hub 125. A supply roll 121 of the second flexible carrier film 120 is positioned on the second flexible carrier supply hub 125. In some implementations, the second flexible carrier film 120 may be formed of the same polymer material (e.g., PET) as the first flexible carrier film 110. An alkali metal film is positioned on the upper side 120U of the second flexible carrier film 120 such that when the second flexible carrier film 120 and the flexible substrate stack 130 are transported through the laser lift-off unit 200, the alkali metal film faces the lower surface 130L of the flexible substrate stack 130. The alkali metal film... Figure 2 The image shows an alkali metal film 242 after contacting a flexible substrate stack 130 during a laser lift-off process.

[0044] In some implementations, the alkali metal film on the first flexible carrier film 110 and the second flexible carrier film 120 may be formed of lithium metal, another alkali metal (e.g., sodium), or an alloy including an alkali metal.

[0045] The transfer system 100 includes a flexible substrate stack supply hub 135. A supply roll 131 of the flexible substrate stack 130 is positioned on the flexible substrate stack supply hub 135. The flexible substrate stack 130 may include one or more layers. In some implementations, such as for a lithium metal anode device, the flexible substrate stack 130 may include a current collector. In some implementations, such as for a pre-lithiation process, the flexible substrate stack 130 may include an anode material. In other implementations, for a pre-lithiation process, the flexible substrate stack 130 may include both a current collector and an anode material. In yet another implementation, the flexible substrate stack 130 may be or include spacers, such as polymer spacers. The flexible substrate stack 130 may be or include a current collector or a current collector having an anode material formed thereon. In one or more implementations that can be combined with other implementations, the flexible substrate stack 130 includes a roll-based substrate, for example, the current collector may be a roll-based substrate. Any suitable current collector can be used. The current collector may include, but is not limited to, aluminum (Al), copper (Cu), zinc (Zn), nickel (Ni), cobalt (Co), manganese (Mn), chromium (Cr), stainless steel, cladding materials, metallized plastics, paper, stainless steel, metal mesh, or combinations thereof. Any suitable anode material may be used. During the laser lift-off process, the alkali metal films 241, 242 contact the flexible substrate stack 130. For example, the exposed surfaces of the alkali metal films 241, 242 contact the surface of the flexible substrate stack 130. In some implementations, where the flexible substrate stack 130 comprises only a current collector substrate, the exposed surfaces of the alkali metal films 241, 242 contact the surface of the current collector substrate. In some implementations, where the flexible substrate stack 130 includes an anode material, the exposed surfaces of the alkali metal films 241, 242 contact the surface of the anode material to pre-lithiate the anode material.

[0046] The transfer system 100 further includes a laser stripping unit 200. The laser stripping unit 200 includes a first laser source assembly 201a and a second laser source assembly 201b. A first flexible carrier film 110, a second flexible carrier film 120, and a flexible substrate stack 130 are arranged to transport along a path extending between the first laser source assembly 201a and the second laser source assembly 201b. When the first flexible carrier film 110, the second flexible carrier film 120, and the flexible substrate stack 130 are transported between the first laser source assembly 201a and the second laser source assembly 201b, the flexible substrate stack 130 is positioned between the first flexible carrier film 110 and the second flexible carrier film 120. Energy from the laser source assemblies 201a and 201b separates each alkali metal film 241, 242 from its corresponding flexible carrier film 110, 120, enabling each alkali metal film 241, 242 to be transferred to the flexible substrate stack 130. In some implementations, a release layer is disposed on each flexible carrier film 110, 120, located between the corresponding flexible carrier film 110, 120 and the alkali metal film 241, 242 on each corresponding flexible carrier film.

[0047] The transfer system 100 includes a first flexible carrier pick-up hub 116. A pick-up roll 112 of the first flexible carrier film 110 is positioned on the first flexible carrier pick-up hub 116. When the first flexible carrier film 110 is wound onto the first flexible carrier pick-up hub 116, the alkali metal film is no longer located on the first flexible carrier film 110 because the alkali metal film previously located on the first flexible carrier film 110 has been transferred to the flexible substrate stack 130 by the laser stripping unit 200.

[0048] The transfer system 100 includes a second flexible carrier pick-up hub 126. A pick-up roll 122 of the second flexible carrier film 120 is positioned on the second flexible carrier pick-up hub 126. When the second flexible carrier film 120 is wound onto the second flexible carrier pick-up hub 126, the alkali metal film is no longer located on the second flexible carrier film 120 because the alkali metal film previously located on the second flexible carrier film 120 has been transferred to the flexible substrate stack 130 by the laser stripping unit 200.

[0049] The transfer system 100 includes a flexible substrate stack pick-up hub 136. Pick-up rolls 132 of the flexible substrate stack 130 are positioned on the flexible substrate stack pick-up hub 136. The flexible substrate stack 130 includes an alkali metal film on each of its upper surface 130U and lower surface 130L. These lithium films are transferred from corresponding flexible carrier films 110, 120 to the flexible substrate stack 130 via a laser lift-off unit 200.

[0050] The transfer system 100 further includes a plurality of rollers 181-188. In some implementations, each of the rollers 181-188 may be a passivated roller. The rollers 181-188 may help apply appropriate tension to the flexible carrier films 110, 120 and the flexible substrate stack 130, and help change the orientation of the flexible carrier films 110, 120 and the flexible substrate stack 130 as they pass through different sections of the transfer system 100. Some of the rollers 181-188 may also help bring the flexible carrier films 110, 120 closer to or further away from the flexible substrate stack 130. For example, second and third rollers 182, 183 may act as clamping rollers and help bring the flexible carrier films 110, 120 into contact with the flexible substrate stack 130 before the flexible carrier films 110, 120 and the flexible substrate stack 130 are conveyed through the laser stripping unit 200. Additionally, the fourth and fifth rollers 184, 185 provide positions where tension can be applied to the flexible carrier films 110, 120 to peel them off from the flexible substrate stack 130. The sixth roller 186 and the seventh roller 187 provide positions where additional tension can be applied to the first flexible carrier film 110 and the second flexible carrier film 120 to peel them off from the flexible substrate stack 130. In some implementations, one or more of the rollers 181-188 may alternatively be rods, such as metal rods, that can apply tension to the carrier or flexible substrate during movement.

[0051] Furthermore, in some implementations, rollers 184, 185 may be positioned in a controlled atmosphere, such as an atmosphere excluding nitrogen, an atmosphere excluding oxygen, an inert gas atmosphere without any significant amount of other gases, a vacuum environment, or an atmosphere that includes one or more gases (such as carbon dioxide) supplied to the internal volume of the passivation unit 190 but excludes any gases (such as nitrogen) known to negatively affect the performance of the alkali metal film. In other implementations, the controlled atmosphere includes inert gases such as argon, CO2, NO, N2, O2, or combinations thereof. In one implementation, rollers 184, 185 and the corresponding passivation unit 190 are housed in the same enclosure having the controlled atmosphere described above, such that newly exposed alkali metal surfaces are not exposed to uncontrolled atmospheres, such as atmospheres including nitrogen. In some implementations, each part of the transfer system 100 is in a controlled atmosphere, such as an environment excluding nitrogen and oxygen.

[0052] The transfer system 100 may further include actuators (not shown) configured to rotate each hub 115, 116, 125, 126, 135, 136, such that the flexible carrier films 110, 120 and the flexible substrate stack 130 can be transported from the corresponding supply hubs 115, 125, 135 through the laser stripping unit 200 and to the corresponding pick-up hubs 116, 126, 136. The transfer system 100 may further include one or more actuators (not shown) to rotate the various hubs and rollers of the transfer system 100. The rotational speed of the actuators can be adjusted to control the transport speed of the flexible substrate stack 130 and the flexible carrier films 110, 120 through the transfer system 100.

[0053] In the transfer system 100, a flexible substrate stack 130 is transported along a path starting from a supply roll 131 supported by a supply hub 135, passing through a first roller 181, between second and third rollers 182, 183, between laser source assemblies 201a, 201b, between fourth and fifth rollers 184, 185, through a passivation unit 190, through an eighth roller 188, and reaching a pick-up roll 132 surrounding a pick-up hub 136. The pick-up hub 136 is configured to rotate and assist in transporting the flexible substrate through the internal volume of the passivation unit 190 after the flexible substrate stack 130 has passed between the first laser source assembly 201a and the second laser source assembly 201b. Similarly, pick-up hubs 116, 126 are configured to rotate and assist in transporting the flexible carrier along a path between supply hubs 115, 125 and pick-up hubs 116, 126. The transfer system 100 may also include a controller 105 for controlling the processes performed by the transfer system 100. Controller 105 can be any type of controller used in an industrial environment, such as a programmable logic controller (PLC). Controller 105 includes a processor 107, a memory 106, and input / output (I / O) circuitry 108. Controller 105 may further include one or more components (not shown), such as one or more power supplies, a clock, communication components (e.g., a network interface card), and a user interface typically found in semiconductor equipment controllers.

[0054] Memory 106 may include non-transitory memory. Non-transitory memory may be used to store programs and settings as described below. Memory 106 may include one or more readily available memory types, 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)).

[0055] Processor 107 is configured to execute various programs stored in memory 106, such as programs configured to execute any of the methods 600, 800, and 900 described herein. During the execution of these programs, controller 105 can communicate with I / O devices via I / O circuitry 108. For example, during the execution of these programs and communication via I / O circuitry 108, controller 105 can control outputs (e.g., actuators connected to different hubs and laser stripping units 200). Memory 106 may further include various operational settings for controlling transfer system 100. For example, settings may include speed settings for actuators connected to hubs and settings for controlling passivation unit 190 described below.

[0056] Figure 2 A schematic side view illustrating an example of a laser stripping unit 200, according to one or more implementations of this disclosure, that can be used with the described transfer system. The laser stripping unit 200 may be part of the transfer system shown herein or may be a standalone unit. The laser stripping unit 200 is configured to provide electromagnetic energy to alkali metal films 241, 242 to create an interfacial reaction with a release layer, interface layer, or both a release layer and interface layer between the alkali metal films 241, 242 and the flexible carrier films 110, 120 (e.g., PET), thereby enabling subsequent removal of the flexible carrier films 110, 120 from the alkali metal films 241, 242 at the activated interface. The laser stripping unit 200 includes a first laser source assembly 201a positioned to deliver electromagnetic energy toward a first flexible carrier film 110 and a second laser source assembly 201b positioned to deliver electromagnetic energy toward a second flexible carrier film 120. A first flexible carrier film 110, a second flexible carrier film 120 having alkali metal films 241 and 242 formed thereon respectively, and a flexible substrate stack 130 are arranged to be transported along a path extending between a first laser source assembly 201a and a second laser source assembly 201b. When the first flexible carrier film 110, the second flexible carrier film 120, and the flexible substrate stack 130 are transported between the first laser source assembly 201a and the second laser source assembly 201b, the flexible substrate stack 130 is positioned between the first flexible carrier film 110 and the second flexible carrier film 120.

[0057] The first laser source assembly 201a and the second laser source assembly 201b include at least one of laser sources 202a-b and optical source assemblies 206a-b. Laser sources 202a-b are configured to generate laser beams 230a-b, and optical source assemblies 206a-b are configured to direct the laser beams 230a-b toward a back surface, such as the upper surface 110U of the first flexible carrier film 110 and the lower surface 110L of the second flexible carrier film 120. In one or more implementations, the first laser source assembly 201a and the second laser source assembly 201b are positioned such that the laser beams 230a-b are directed toward a back surface, such as the upper surface 110U of the first flexible carrier film 110 and the lower surface 110L of the second flexible carrier film 120. Figure 2 The offsets shown are relative to each other. For example, reference Figure 2 The second laser source component 201b is positioned downstream of the first laser source component 201a. Additionally, although... Figure 2 The LLO process is shown to be performed with free span orientation, but the roller or another surface can be as follows: Figure 3-5 The laser source assembly 201a and the laser source assembly 201b are positioned opposite each of the first laser source assembly 201a and the second laser source assembly 201b.

[0058] In one or more implementations that can be combined with other implementations, the laser source 202a-b can be a solid-state laser, such as a diode-pumped solid-state laser having an optical fiber, rod, or slab gain medium, configured to generate a laser beam 230a-b. The laser beam 230a-b can be a continuous or pulsed laser beam. The laser fiber, rod, or slab can be formed from any suitable laser crystal material, including neodymium-doped yttrium aluminum garnet (Nd:YAG; Nd:Y3Al5O4). 12 Yttrium-doped YAG (Yb:YAG), neodymium-doped yttrium vanadate (Nd:YVO4; Nd:YVO4), and alexandrite are used. In certain implementations, the laser rod or slab has a surface-pumped geometry. In certain implementations, the laser slab has an edge-pumped geometry. Other types of lasers, such as fiber lasers or gas lasers, may also be used. Suitable laser sources include, but are not limited to, IR fiber lasers, UV lasers, or green lasers. In other implementations, laser sources 202a-b may be replaced by flash lamps as described.

[0059] In certain implementations, laser source 202a-b is an infrared laser source configured to operate at infrared (IR) wavelengths to remove alkali metal segments on an alkali metal-coated substrate. Laser source 202a-b can generate pulsed laser beams 230a-b. In some implementations described herein, the frequency, pulse width, and pulse energy of the laser beam 230a-b generated by laser source 202a-b can be adjusted (e.g., adjustable) according to the material being removed, the target lateral dimension of the segment being removed, and the removal depth. Furthermore, the movement speed, number of pulses, beam profile, and focused spot size of the laser beam 230a-b can be tuned.

[0060] In any form, the laser beam 230a-b generated by the laser source 202a-b is projected (e.g., emitted) toward the flexible stack 240 via the optical source assembly 206a-b. The optical source assembly 206a-b is optically coupled to the laser source 202a-b and includes any suitable image projection means for pointing the laser beam 230a-b toward the flexible stack 240 for a laser lift-off process. In a particular implementation, the optical source assembly 206a-b includes a scanner 232a-b, such as a single-axis or multi-axis large-angle galvanometer optical scanner (i.e., a galvanometer scanner). The term "galvanometer scanner" refers to any means that changes the projection or reflection angle of the laser beam 230a-b in response to an electronic signal from the controller 105 to scan the laser beam 230a-b across the flexible stack 240. The scanner 232a-b may also be a polygon scanner, an electro-optic scanner, an acousto-optic device, or a combination thereof. Multiple segments of alkali metal on the flexible stack 240 are activated via a laser ablation process using scanners 232a-b, without the need for mechanical translation of the flexible stack 240 itself, except for the surface scanning laser beams 230a-b across the flexible stack 240. Scanners 232a-b may further include any suitable features that facilitate the activation of the materials and structures described herein, such as digital servo feedback, low drift, fast dynamic response, and precise calibration capabilities.

[0061] In one or more implementations that can be combined with other implementations, the optical source assembly 206a-b further includes one or more scanning lenses 234a-b having a large field of view covering the entire area of ​​the flexible stack 240. In one or more implementations that can be combined with other implementations, two or more scanning lenses 234a-b can be used for laser removal of different types of materials, each scanning lens being specific to the wavelength range of the laser source 202a-b. The scanning lenses 234a-b can be telecentric lenses, F-θ lenses, or combinations thereof. During operation, the laser beam 230a-b projected by the optical source assembly 206a-b is directed towards the flexible stack 240.

[0062] The laser stripping unit 200 includes a housing 215 disposed around an inner volume 208. The housing 215 includes an upper housing 215U and a lower housing 215L. The flexible stack 240 is transported through the inner volume 208 as it is moved toward the pick-up hub 136. The inner volume 208 includes an upper volume 208U above the flexible stack 240 and a lower volume 208L below the flexible stack 240.

[0063] In some implementations, the laser ablation unit 200 further includes a plurality of seals 251-254. The seals 251-254 may be formed of a compressible material. The seals 251-254 can be used to maintain a separate environment within the internal volume 208 relative to the environment surrounding the laser ablation unit 200. For example, the internal volume 208 may have different gas concentrations and different temperatures and / or pressures relative to the environment surrounding the laser ablation unit 200.

[0064] The laser ablation unit 200 may further include an atmosphere control system 297 coupled to the housing 215. The atmosphere control system 297 includes a throttle valve and a pump for controlling chamber pressure. The atmosphere control system 297 may additionally include a gas source for supplying process gas or other gases to the internal volume 208 of the laser ablation unit 200. The atmosphere control system 297 may be controlled by a controller 105. In one or more implementations, the atmosphere control system 297 may assist in controlling the pressure within a target range during the laser ablation process. In one example, the pressure during the laser ablation process may be controlled at atmospheric pressure, such as ambient pressure.

[0065] Figure 3 A schematic side view of another flexible substrate transfer system 300 incorporating a laser lift-off unit, according to one or more implementations of this disclosure, is illustrated. The flexible substrate transfer system 300 is configured to process the lower surface 130L and upper surface 130U of a flexible substrate stack 130 sequentially, rather than simultaneously. Although Figure 3 The housing is not shown, but the components of the flexible substrate transfer system 300 may be positioned in a housing 100 similar to that of the flexible substrate transfer system 100.

[0066] The flexible substrate transfer system 300 includes a plurality of rollers 381-388. In some implementations, each of the rollers 381-388 may be a passivated roller. The rollers 381-388 may facilitate applying appropriate tension to the flexible carrier films 110, 120 and the flexible substrate stack 130, and facilitate changing the orientation of the flexible carrier films 110, 120 and the flexible substrate stack 130 as they pass through different portions of the transfer system 300. For example, the first roller 381 and the fifth roller 385 provide positions where additional tension can be applied to the first flexible carrier film 110 and the second flexible carrier film 120. Some of the rollers 381-388 may also facilitate bringing the flexible carrier films 110, 120 closer to or further away from the flexible substrate stack 130. For example, in one or more implementations, the second and third rollers 382, ​​383 serve as clamping rollers and facilitate contact between the second flexible carrier film 120 and the flexible substrate stack 130 before the second flexible carrier film 120 and the flexible substrate stack 130 are conveyed through the second laser source assembly 201b. In one or more other implementations, the second and third rollers 382, ​​383 serve as calendering rollers. The calendering rollers not only facilitate contact between the second flexible carrier film 120 and the flexible substrate stack 130 before the second flexible carrier film 120 and the flexible substrate stack 130 are transported through the second laser source assembly 201b, but also apply sufficient pressure to laminate the second flexible carrier film 120 to the flexible substrate stack 130. Additionally, the fourth roller 384 provides a position where tension can be applied to the second flexible carrier film 120 to peel it from the flexible substrate stack 130. The sixth and seventh rollers 386, 387 may serve as pinch rollers or calendering rollers and facilitate contact between the first flexible carrier film 110 and the flexible substrate stack 130 before the first flexible carrier film 110 and the flexible substrate stack 130 are transported through the first laser source assembly 201a. The eighth roller 388 provides a position where tension can be applied to the first flexible carrier film 110 to peel it from the flexible substrate stack 130. In some implementations, one or more of rollers 381-388 may alternatively be rods, such as metal rods, that can apply tension to the carrier or flexible substrate during movement.

[0067] In one or more implementations that can be combined with other implementations, the flexible substrate transfer system 300 further includes a diaphragm supply hub 315. A supply roll 311 of the diaphragm 310 is positioned on the diaphragm supply hub 315. The diaphragm supply hub 315 is positioned downstream of the first laser source assembly 201a and / or the in-line passivation unit 190 (if present) and upstream of the pick-up hub 136. The diaphragm 310 can serve as a protective film that protects the alkali metal film from atmosphere exposure and / or damage when the flexible substrate stack 130 is collected on the pick-up hub 136 as a pick-up roll 132. The diaphragm 310 may include any suitable material for protecting the underlying film. In some implementations, the diaphragm 310 is formed of a polymeric material, a metallic material, or a combination of polymeric and metallic materials (e.g., metallized plastic). Examples of suitable membrane materials include polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polyimide (PI), polymethyl methacrylate (PMMA), cellulose triacetate (TAC), polypropylene (PP), polyethylene (PE), polycarbonate (PC), stainless steel, multilayers thereof, or combinations thereof.

[0068] refer to Figure 3In operation, the flexible substrate stack 130 and the second flexible carrier film 120 are transported toward the second laser source assembly 201b. As the flexible substrate stack 130 and the second flexible carrier film 120 travel between the second roller 382 and the third roller 383, the rollers 382 and 383 provide sufficient pressure to the flexible substrate stack 130 and the second flexible carrier film 120, such that the flexible substrate stack 130 and the second flexible carrier film 120 contact each other and / or are laminated before or during their travel through the second laser source assembly 201b. The second laser source assembly 201b provides laser energy to the second alkali metal film 242 sandwiched between the lower surface 130L of the flexible substrate stack 130 and the second flexible carrier film 120, to generate an interfacial reaction with the release layer, interface layer, or both release layer and interface layer between the second alkali metal film 242 and the second flexible carrier film 120, thereby enabling the subsequent removal of the second flexible carrier film 120 from the second alkali metal film 242 at the activated interface. The fourth roller 384 applies tension to the second flexible carrier film 120 to peel it from the flexible substrate stack 130. The second flexible carrier film 120 is collected on the second flexible carrier pickup hub 126. The flexible substrate stack 130, having a second alkali metal film formed on its lower surface 130L, is transferred to the sixth roller 386 and the seventh roller 387, which provide sufficient pressure to the flexible substrate stack 130 and the first flexible carrier film 110, such that the upper surface 130L of the flexible substrate stack 130 and the lower surface 110L of the first flexible carrier film 110 come into contact with each other and / or are laminated before or during travel through the first laser source assembly 201a. The first laser source assembly 201a provides laser energy to the first alkali metal film 241 sandwiched between the upper surface 130U of the flexible substrate stack 130 and the lower surface 110L of the first flexible carrier film 110, thereby generating an interfacial reaction between the first alkali metal film 241 and the release layer, interface layer, or both release layer and interface layer between the first alkali metal film 241 and the first flexible carrier film 110, thus enabling the subsequent removal of the first flexible carrier film 110 from the first alkali metal film 241 at the activated interface. The eighth roller 388 applies tension to the first flexible carrier film 110 to peel it off from the flexible substrate stack 130. The first flexible carrier film 110 is collected on the first flexible carrier pickup hub 116. A flexible substrate stack 130 having a second alkali metal film 242 attached to a lower surface 130L and a first alkali metal film 241 attached to an upper surface 130U travels through an in-line passivation unit 190 (if present), in which passivation films are formed on the first alkali metal film 241 and the second alkali metal film 242 formed on the second alkali metal film 242. The flexible substrate stack 130 having a second alkali metal film 242 attached to a lower surface 130L and a first alkali metal film 241 attached to an upper surface 130U can be combined with a diaphragm provided by a diaphragm supply hub 315 before or during final winding on the flexible substrate stack pick-up hub 136.

[0069] Figure 4 A schematic side view of another flexible substrate transfer system 400 incorporating a laser lift-off unit, according to one or more implementations of this disclosure, is illustrated. The flexible substrate transfer system 400 is configured to sequentially process the lower surface 130L and upper surface 130U of a flexible substrate stack 130, similar to... Figure 3 The flexible substrate transfer system 300 is shown. The flexible substrate transfer system 400 includes a single clamping / rolling, followed by sequential processing of the lower surface 130L and the upper surface 130U. Although Figure 4 The housing is not shown, but components of the flexible substrate transfer system 400 may be positioned within a housing 100 similar to that of the flexible substrate transfer system 100.

[0070] The flexible substrate transfer system 400 includes a plurality of rollers 481-486. In some implementations, one or more of rollers 481-486 may be passivated rollers. Rollers 481-486 may facilitate the application of appropriate tension to the flexible carrier films 110, 120 and the flexible substrate stack 130, and facilitate the change of orientation of the flexible carrier films 110, 120 and the flexible substrate stack 130 as they pass through different portions of the transfer system 400. For example, a first roller 481 provides a location where additional tension can be applied to a second flexible carrier film 120. Some of rollers 481-486 may also facilitate bringing the flexible carrier films 110, 120 closer to or further away from the flexible substrate stack 130. For example, the second and third rollers 482 and 483 can be used as pinch rollers or calendering rollers, and facilitate contact between the first flexible carrier film 110 and the second flexible carrier film 120 and the opposite sides of the flexible substrate stack 130 before or during the transport of the first flexible carrier film 110, the second flexible carrier film 120, and the flexible substrate stack 130 through the second laser source assembly 201b. Additionally, the fourth roller 484 provides a position where tension can be applied to the second flexible carrier film 120 to peel it from the flexible substrate stack 130. The fourth roller 484 can be positioned to peel the second flexible carrier film 120 after the substrate stack is exposed to the second laser source assembly 201b but before the substrate stack is exposed to the first laser source assembly 201a. The fifth roller 485 provides a processing surface on which the first flexible carrier film 110 and the flexible substrate stack 130 travel during exposure to laser energy from the first laser source assembly 201a. The sixth roller 486 provides a position where tension can be applied to the first flexible carrier film 110 to peel the first flexible carrier film 110 from the flexible substrate stack 130. In some implementations, one or more of the rollers 481-486 may alternatively be a rod, such as a metal rod, that can apply tension to the carrier or flexible substrate during movement.

[0071] In one or more implementations that can be combined with other implementations, the flexible substrate transfer system 400 further includes a diaphragm supply hub 315. A supply roll 311 of the diaphragm 310 is positioned on the diaphragm supply hub 315. The diaphragm supply hub 315 is positioned downstream of the first laser source assembly 201a and / or the in-line passivation unit 190 (if present) and upstream of the pick-up hub 136.

[0072] refer to Figure 4In operation, the first flexible carrier film 110, the second flexible carrier film 120, and the flexible substrate stack 130 are conveyed toward the second laser source assembly 201b. As the flexible substrate stack 130 and the second flexible carrier film 120 travel between the second roller 482 and the third roller 483, the rollers 482 and 483 provide sufficient pressure to the first flexible carrier film 110, the second flexible carrier film 120, and the flexible substrate stack 130, such that the first flexible carrier film 110, the second flexible carrier film 120, and the flexible substrate stack 130 contact each other before or during their travel through the second laser source assembly 201b. In one or more implementations, at least one of the second roller 482 and the third roller 483 is a calendering roller, and the first flexible carrier film 110, the second flexible carrier film 120, and the flexible substrate stack 130 are laminated together by the pressure applied by the calendering roller. In one or more implementations, the second roller 482 and the third roller 483 are clamping rollers. The second laser source assembly 201b provides laser energy to the second alkali metal film 242 sandwiched between the lower surface 130L of the flexible substrate stack 130 and the second flexible carrier film 120, to generate an interfacial reaction with the release layer, interface layer, or both release layer and interface layer between the second alkali metal film 242 and the second flexible carrier film 120, thereby enabling subsequent removal of the second flexible carrier film 120 from the second alkali metal film 242 at the activated interface. The fourth roller 484 applies tension to the second flexible carrier film 120 to peel it from the flexible substrate stack 130. The second flexible carrier film 120 is collected on the second flexible carrier pickup hub 126. The flexible substrate stack 130, having a second alkali metal film formed on its lower surface 130L and the lower surface 110L of the first flexible carrier film 110 contacting the upper surface 130U of the flexible substrate stack 130, travels on the fifth roller 485 before or during its passage through the first laser source assembly 201a. The first laser source assembly 201a provides laser energy to the first alkali metal film 241 sandwiched between the upper surface 130U of the flexible substrate stack 130 and the lower surface 110L of the first flexible carrier film 110, thereby generating an interfacial reaction with the release layer, interface layer, or both release layer and interface layer between the first alkali metal film 241 and the first flexible carrier film 110, thus enabling subsequent removal of the first flexible carrier film 110 from the first alkali metal film 241 at the activated interface. A sixth roller 486 applies tension to the first flexible carrier film 110 to peel it from the flexible substrate stack 130. The first flexible carrier film 110 is collected on the first flexible carrier pickup hub 116. The flexible substrate stack 130, having a second alkali metal film 242 attached to the lower surface 130L and a first alkali metal film 241 attached to the upper surface 130U, travels through an in-line passivation unit 190 (if present), in which passivation films are formed on the first alkali metal film 241 and the second alkali metal film 242.The flexible substrate stack 130, having a second alkali metal film 242 attached to the lower surface 130L and a first alkali metal film 241 attached to the upper surface 130U, can be combined with a diaphragm provided by a diaphragm supply hub 315 before finally being wound onto the flexible substrate stack pick-up hub 136.

[0073] Figure 5 A schematic side view illustrates yet another example flexible substrate transfer system 500 incorporating a laser lift-off unit according to one or more implementations of this disclosure. The flexible substrate transfer system 500 is configured to sequentially process the lower surface 130L and upper surface 130U of a flexible substrate stack 130, similar to... Figure 3 The flexible substrate transfer system 300 shown and Figure 4 The flexible substrate transfer system 400 shown is illustrated. Although... Figure 5 The housing is not shown, but components of the flexible substrate transfer system 500 may be positioned within a housing 100 similar to that of the flexible substrate transfer system 100. The flexible substrate transfer system 500 further includes a first in-line slitting assembly 530a positioned to slit a first flexible carrier film 110 after the flexible carrier has been peeled from the processed flexible substrate stack 130, and a second in-line slitting assembly 530b positioned to slit a second flexible carrier film 120. In some implementations where it is desirable to transfer only a portion of the alkali metal film formed on the flexible carrier (e.g., transferring alkali metal over half the width of the flexible carrier to the flexible substrate stack 130), the remaining unprocessed portion of the alkali metal film still formed thereon is separated from the processed portion of the flexible carrier by the in-line slitting assemblies 530a-b and collected on a separate pick-up hub for reuse. The in-line slitting assemblies 530a-b include blades, such as rotary blades, for cutting the flexible carrier film.

[0074] The flexible substrate transfer system 500 includes a plurality of rollers 581-589. In some implementations, one or more of rollers 581-589 may be passivated rollers. Rollers 581-589 may facilitate the application of appropriate tension to the flexible carrier films 110, 120 and the flexible substrate stack 130, and facilitate the change of orientation of the flexible carrier films 110, 120 and the flexible substrate stack 130 as they pass through different portions of the transfer system 500. For example, a first roller 581 provides a location where additional tension can be applied to a second flexible carrier film 120. Some of rollers 581-589 may also facilitate bringing the flexible carrier films 110, 120 closer to or further away from the flexible substrate stack 130. For example, the second and third rollers 582, 583 can be used as pinch rollers and / or calendering rollers, and facilitate contact between the first flexible carrier film 110 and the second flexible carrier film 120 and the opposite sides of the flexible substrate stack 130 before or during the transport of the first flexible carrier film 110, the second flexible carrier film 120 and the flexible substrate stack 130 through the second laser source assembly 201b. Additionally, the fourth roller 584 provides a position to apply tension to the second flexible carrier film 120 to peel it from the flexible substrate stack 130. The fourth roller 584 can be positioned to peel the second flexible carrier film 120 after the substrate stack is exposed to the second laser source assembly 201b but before the substrate stack is exposed to the first laser source assembly 201a. The fifth roller 585 can be positioned downstream of the fourth roller 584 and upstream of the pick-up hub 126 for collecting the processed portion of the second flexible carrier film 120 and the pick-up roll 522 for collecting the unprocessed portion of the second flexible carrier film 120. The second in-line slitting assembly 530b is positioned downstream of the fourth roller 584 and upstream of the fifth roller 585, pick-up hub 126, and pick-up hub 526. The second in-line slitting assembly 530b is positioned to slit the second flexible carrier film 120 after it has been peeled from the processed flexible substrate stack 130. The second in-line slitting assembly 530b cuts the flexible carrier film 120 into a processed portion collected as pick-up roll 122 on pick-up hub 126 and an unprocessed portion collected as pick-up roll 522 on pick-up hub 526.

[0075] A sixth roller 586 provides a processing surface on which the first flexible carrier film 110 and the flexible substrate stack 130 travel during exposure to laser energy from the first laser source assembly 201a. The sixth roller 586 provides a location where tension can be applied to the first flexible carrier film 110 to peel it from the flexible substrate stack 130. A seventh roller 587 is positioned to peel the first flexible carrier film 110 after the substrate stack has been exposed to the first laser source assembly 201a. An eighth roller 588 is positioned downstream of the seventh roller 587 and upstream of a pick-up hub 116 for collecting processed portions of the first flexible carrier film 110 and a pick-up hub 516 for collecting unprocessed portions of the first flexible carrier film 110. A first in-line slitting assembly 530a is positioned downstream of the seventh roller 587 and upstream of the eighth roller 588, pick-up hub 116, and pick-up hub 516. The first online slitting assembly 530a is positioned to slit the first flexible carrier film 110 after it has been peeled from the processed flexible substrate stack 130. The first online slitting assembly 530a cuts the flexible carrier film 110 into a processed portion collected as a pick-up roll 112 on a pick-up hub 116 and an unprocessed portion 512 collected on a pick-up hub 516. The flexible substrate stack 130, having a second alkali metal film 242 attached to the lower surface 130L and a first alkali metal film 241 attached to the upper surface 130U, then proceeds through an online passivation unit 190 (if present), in which passivation films are formed on the first alkali metal film 241 and the second alkali metal film 242. The flexible substrate stack 130, having a second alkali metal film 242 attached to the lower surface 130L and a first alkali metal film 241 attached to the upper surface 130U, is then reoriented by a ninth roller 589 and can be combined with a diaphragm provided by a diaphragm supply hub 315 before or during final winding on the flexible substrate stack pick-up hub 136.

[0076] In some implementations, one or more of rollers 581-589 may alternatively be rods, such as metal rods, that can apply tension to the carrier or flexible substrate during movement.

[0077] Figure 6 A flowchart illustrating selected operations of a method 600 for forming an energy storage device via a laser ablation process according to one or more implementations of the present disclosure is provided. Figures 7A-7D Views illustrating various stages of manufacturing an energy storage device according to one or more implementations of this disclosure are provided. Although Figures 7A-7D It is described in conjunction with method 600, but it should be understood that... Figures 7A-7D The structure disclosed herein is not limited to method 600, but can exist independently of method 600. Similarly, although method 600 is combined with... Figures 7A-7D The method described, but it should be understood, is not limited to method 600. Figures 7A-7DThe structure is not publicly available, but can be independent of... Figures 7A-7D The publicly disclosed structure exists independently. It should be understood that... Figures 7A-7D Only a partial schematic diagram of the energy storage device structure 700 is shown, and the energy storage device structure 700 may include any number of additional layers and / or additional materials common to energy storage devices, which are not shown for simplicity. It should also be noted that, although... Figure 6 The method 600 illustrated herein is described sequentially, but other process sequences, including one or more operations that have been omitted and / or added, and / or rearranged in another desired order, also fall within the scope of the implementation of this disclosure provided herein. Method 600 can be performed using any of the aforementioned flexible substrate transfer systems 100, 300, 400, and 500.

[0078] refer to Figure 7A In operation 610, the flexible substrate stack 130, the first flexible carrier film 110, and the second flexible carrier film 120 are transported toward a laser lift-off unit, such as laser lift-off unit 200. The first flexible carrier film 110 and the second flexible carrier film 120 each include a polymer substrate 702a-b as described. The first flexible carrier film 110 and the second flexible carrier film 120 may further include release films 710a-b, respectively. The release films 710a-b facilitate the removal of alkali metal films 241, 242 from the underlying polymer substrate 702a-b.

[0079] In one or more implementations, the release film 710a-b may be or include a polymeric material capable of photoinduced depolymerization. In one or more implementations, the polymeric material may be or include a poly(olefin sulfone) material capable of photoinduced depolymerization. The poly(olefin sulfone) may be combined with a photoalkali generator (PBG). The poly(olefin sulfone) may be doped with a photosensitizer, such as pyridine N-oxide. The depolymerization process may be initiated by, for example, X-ray, electron beam radiation, or low-energy IR radiation. Suitable poly(olefin sulfone) materials include poly(1-butene sulfone) (PBS), poly(1-pentane sulfone) (PPS), poly(1-hexane sulfone) (PHS), poly(1-octene sulfone) (POS), poly(cyclopentene sulfone), poly(2-methyl-1-butene sulfone) (PMBS), poly(2-methyl-1-pentene sulfone) (PMPS), poly(2-methyl-1-hexene sulfone) (PMHS), poly(2-methyl-1-nonene sulfone) (PMNS), poly(cyclohexene sulfone), or combinations thereof. In other implementations, the release film 710a-b may be or include one or more of fluorocarbons, silicones, latexes, AlOx, LiF, AlOOH, Ag, AgF, Bi, or Sn. The release layer may also be an engineered polymer tailored for high laser absorption. Optionally, a laser-absorbing material may also be patterned on top of a plastic substrate, with or without a release layer, to distinguish the areas to be transferred from the non-transfer areas of the alkali metal or alloy, thereby achieving the desired patterned transfer.

[0080] The flexible substrate stack 130 may include one or more layers. In some implementations, such as for a lithium metal anode device, the flexible substrate stack 130 may include a current collector substrate 720. In some implementations, such as for a pre-lithiation process, the flexible substrate stack 130 may further include an anode film 730a-b. In other implementations, for a pre-lithiation process, the flexible substrate stack 130 may include both the current collector substrate 720 and the anode film 730a-b. The flexible substrate stack 130 may be or include the current collector substrate 720 or a current collector substrate 720 having an anode film 730a-b formed thereon. In one or more implementations that can be combined with other implementations, the flexible substrate stack 130 includes a roll-to-roll substrate, for example, the current collector substrate 720 may be a roll-to-roll substrate. Any suitable current collector may be used. The current collector may include, or be, but is not limited to, aluminum (Al), copper (Cu), zinc (Zn), nickel (Ni), cobalt (Co), manganese (Mn), chromium (Cr), stainless steel, cladding materials, metallized plastics, paper, stainless steel, metal mesh, or combinations thereof. Any suitable anode material may be used. The anode film 730a-b may include, or be, but is not limited to, graphite, silicon, graphite silica, graphite silica, silicon, or combinations thereof.

[0081] The flexible substrate stack 130 may be exposed to a surface activation process prior to the alkali metal transfer process. This surface activation process enhances the bonding between the alkali metal film and the flexible substrate stack 130 (e.g., current collector substrate 720 or anode film 730a-b). The surface activation process may include exposure to ultraviolet (UV) energy or plasma. The surface activation process may include corona surface treatment processes, atmospheric plasma treatment processes, or combinations thereof.

[0082] In one or more implementations, the surface activation process is a plasma treatment process, such as a corona discharge treatment process or an atmospheric plasma treatment process. The performed surface activation process includes supplying a mixture of process gases to the treatment area. Plasma is then formed from the process gas mixture to plasma treat the surface of the flexible substrate stack 130, thereby activating at least a portion of the flexible substrate stack 130 to an excited state, forming a treated flexible substrate stack with a treated upper surface, which subsequently enhances the bonding between the alkali metal film and the flexible substrate stack 130.

[0083] In one or more implementations, the processed gas mixture includes at least one of an oxygen-containing gas, an inert gas (e.g., argon, helium), or a combination thereof. In one or more implementations, the oxygen-containing gas supplied to the processing area includes oxygen (O2), ozone (O3), oxygen radicals (O*), ionized oxygen atoms, carbon dioxide (CO2), and nitric oxide (NO). x At least one of the following: water vapor, or a combination thereof. Other oxygen-containing gases may also be used. The one or more oxygen-containing gases may be introduced together with one or more inert gases (such as nitrogen, helium, or argon).

[0084] In one or more implementations involving oxidation, a gas source supplies oxygen (O2) to an ozone generator via a mass flow controller, which converts most of the oxygen into ozone (O3). The resulting oxygen-based O2 and O3 mixture, along with possibly some oxygen radicals O* and ionized oxygen atoms or molecules, is delivered to a processing region. The oxygen-based gas reacts within the processing region with the surface of a flexible substrate stack 130 that has been heated to a predetermined, preferably low-temperature environment. Ozone is a metastable molecule that spontaneously and rapidly dissociates, with the reaction O3 → O2 + O*, where O* is a radical that reacts very rapidly with any available oxidizable material. Ozone generators can be implemented in various forms, including capacitively or inductively coupled plasma or UV lamp sources.

[0085] Corona treatment can be performed using cryogenic corona discharge plasma to alter the surface energy of the electrode structure. The corona treatment discharge process may include generating ionized corona discharge plasma. The generated corona discharge plasma may be positively or negatively charged. In one or more implementations, the corona is positive. In other implementations, the corona is negative. In some implementations, the corona treatment portion is carried out under atmospheric or partial pressure, under vacuum, or a combination thereof.

[0086] In one or more implementations, the atmospheric plasma processing process includes generating plasma at pressures greater than or equal to 500 Torr, 600 Torr, 700 Torr, 750 Torr, or 755 Torr and less than or equal to 1000 Torr, 900 Torr, 800 Torr, or 765 Torr, or in the range of 500 Torr to 1000 Torr, or in the range of 600 Torr to 900 Torr, or in the range of 700 Torr to 800 Torr, or in the range of 725 Torr to 775 Torr, or in the range of 750 Torr to 770 Torr. In one or more implementations, the atmospheric plasma processing process includes generating plasma in an ambient or uncontrolled pressure environment. The atmospheric plasma may include chemically nonreactive substances (e.g., argon or helium) and / or chemically reactive substances (e.g., oxygen-containing gases, nitrogen-containing gases, or hydrogen).

[0087] refer to Figure 7B At operation 620, during the laser lift-off process, the first alkali metal film 241 and the second alkali metal film 242 are contacted to opposite sides of the flexible substrate stack 130. For example, one surface of the alkali metal film 241 contacts the first surface of the flexible substrate stack 130, and one surface of the alkali metal film 242 contacts the second surface of the flexible substrate stack 130. In some implementations, when the flexible substrate stack 130 includes only the current collector substrate 720, the surfaces of the alkali metal film 241 and the alkali metal film 242 contact opposite sides of the current collector substrate 720. In some implementations, when the flexible substrate stack 130 includes anode films 730a-b, the surface of the alkali metal film 241 contacts the anode film 730a, and the surface of the alkali metal film 242 contacts the anode film 730b, to pre-lithiate the anode material.

[0088] The laser lift-off process in operation 620 involves exposing a flexible stack 240 having alkali metal films 241, 242 formed thereon to laser energy, such as laser energy provided by a first laser source assembly 201a and a second laser source assembly 201b. In one or more implementations, at operation 620, laser beams 230a-b provided by laser source assemblies 201a-b are respectively guided through the back side of polymer substrates 702a-b to activate the interfaces between the alkali metal films 241, 242 and the first flexible carrier film 110 and the second flexible carrier film 120, such as a lithium-PET interface. Figure 2 As shown, laser beams 230a-b can be guided through the back side of the first flexible carrier film 110 and the second flexible carrier film 120, for example, incident from the plastic substrate or PET side of the flexible carrier films 110, 120. Exposure to laser energy can activate not only the alkali metal films 241, 242, but also portions of the first flexible carrier film 110 and the second flexible carrier film 120. For example, exposure to laser energy can activate a portion of the flexible carrier films 110, 120 (e.g., release films 710a-b), a portion of the polymer substrate 702a-b if release films 710a-b are absent, or simultaneously activate a portion of the flexible carrier films 110, 120 and the release films 710a-b. In one or more implementations, the activated portion may correspond to a void volume. Exposure to laser energy can trigger an alkali metal transfer process, thereby creating void volumes between the alkali metal films 241, 242 and their respective corresponding flexible carrier films 110, 120. This void volume facilitates easier separation of the alkali metal films 241 and 242 from their respective flexible carrier films 110 and 120 during the transfer of the alkali metal films 241 and 242 from the flexible carrier films 110 and 120 to the flexible substrate stack 130. The void volume can be patterned, making it easier to remove portions of the alkali metal films 241 and 242 located above the patterned void volume, thereby forming a pattern during transfer to the flexible substrate stack 130. Furthermore, exposure to laser beams 230a-b can be used to pattern the alkali metal films 241 and 242, allowing for precise patterning of the alkali metal films 241 and 242 from the flexible carrier films 110 and 120 to the flexible substrate stack 130.

[0089] In some implementations that can be combined with other implementations, the release film 710a-b can be or include a polymer material capable of photoinduced depolymerization. At operation 620, selective exposure of the release film 710a-b and / or the polymer substrate 702a-b can also be achieved by selectively heating portions of the release film 710a-b to achieve localized interfacial debonding, which can also be used for pattern transfer.

[0090] In some implementations that can be combined with other implementations, the mechanism of void formation during the laser ablation process is thought to be a combination of plasma generated by photoionization and the recombination of sublimation and lithium.

[0091] refer to Figure 7C At operation 630, the flexible carrier films 110 and 120 are peeled off from the flexible substrate stack 130, for example, when the flexible carrier films 110 and 120 are transported through Figure 1 When rollers 184 and 185 are shown. In some implementations where release films 710a-b are present, the release films 710a-b are removed together with the flexible carrier films 110 and 120. Subsequently, each flexible carrier film 110 and 120 is transported to a corresponding pickup hub, such as pickup hubs 116 and 126.

[0092] refer to Figure 7D Optionally, at operation 640, passivation films 750a-b are formed on the newly transferred alkali metal films 241, 242. For example, a flexible substrate stack 130 including the newly transferred alkali metal films 241, 242 is transported into a passivation unit 190, and the newly exposed surfaces of the alkali metal films 241, 242 are passivated in the corresponding passivation unit 190.

[0093] In some implementations, carbon dioxide (CO2) and one or more of argon (Ar), oxygen (O2), and water vapor are provided to the passivation unit 190 to form a lithium carbonate (Li2CO3) passivation film. In other implementations, sulfur hexafluoride (SF6) and one or more of argon (Ar), hydrogen (H2), oxygen (O2), and water vapor are provided to the passivation unit 190 to form lithium fluoride (LiF), AlO2, etc. x AlOOH or lithium hexafluoride (Li x SF6 passivation film. Other gases that can be used to form passivation films on alkali metal surfaces include carbon monoxide (CO), carbon tetrafluoride (CF4), ammonia (NH3), and other hydrocarbon gases containing oxide, fluoride, and chloride functional groups, as well as single-element gases.

[0094] In one or more implementations that can be combined with other implementations, these gases are exposed to UV radiation to form passivation films 750a-b. The wavelength of the UV radiation can be in the range of about 100 nm to about 270 nm, such as about 185 nm to about 254 nm. Wavelengths in these ranges can dissociate the gas supplied to the passivation unit 190. For example, UV radiation in these wavelength ranges can decompose carbon dioxide (CO2) into CO and O, which can be more reactive than the originally supplied CO2. Similarly, these wavelengths can decompose water (H2O) into H and OH, and oxygen (O2) into O and O3, which can also be more reactive than the originally supplied water vapor or oxygen. In addition, these wavelengths can decompose SF6. The thickness of the passivation layer formed on the alkali metal films 241, 242 can be in the range of about 1 nm to about 1000 nm, such as about 10 nm to about 500 nm. Any of the foregoing values ​​can be used alone to describe an open range, or in combination to describe a closed range. In some implementations, the thickness of the alkali metal films 241, 242 can be in the range of about 1 micrometer to about 100 micrometers, such as about 10 micrometers.

[0095] In one or more implementations of operation 640 using passivation unit 190, one or more gases (e.g., CO2) are supplied to passivation unit 190, and UV energy is introduced into the internal volume of passivation unit 190 to increase the passivation reaction rate between alkali metal films 241, 242 and the UV-activated gas. When alkali metal films 241, 242 and flexible substrate stack 130 leave passivation unit 190, the UV-activated gas can effectively passivate alkali metal films 241, 242 on flexible substrate stack 130.

[0096] In one or more implementations that can be combined with other implementations, these gases are exposed to plasma to form passivation films 750a-b. In one example, this is achieved by exposing alkali metal films 241, 242 to one of CO2 and SF6, as well as argon plasma or plasma composed of Ar and H2, O2, H2O, C. x F y Other plasmas, or combinations thereof, are used to form passivation films 750a-b. Examples of suitable perfluorinated carbon gases include carbon tetrafluoride (CF4), hexafluoroethane (C2F6), hexafluoropropylene (C3F6), perfluorocyclobutane (C4F8), perfluorocyclopentene (C5F8), or combinations thereof.

[0097] In one or more implementations of operation 640 using passivation unit 190, one or more gases (e.g., CO2) are supplied to the internal volume of passivation unit 190. RF power is supplied from a corresponding RF power source to the electrodes of plasma generation units located in passivation unit 190 to generate plasma P in the internal volume of each plasma generation unit. The plasma, containing plasma material (e.g., CO2 ions and free radicals), then flows to and reacts with the corresponding alkali metal films 241, 242 to form passivation films 750a-b on the respective surfaces of the alkali metal films 241, 242. As the alkali metal films 241, 242 and the flexible substrate stack 130 leave passivation unit 190, the plasma effectively passivates the alkali metal films 241, 242 on the flexible substrate stack 130.

[0098] At operation 650, passivated alkali metal films 241 and 242 on the flexible substrate stack 130 are transported to pick-up hub 136. Because the surfaces of the alkali metal films 241 and 242 on the flexible substrate stack 130 have been passivated, they can be exposed to the surrounding environment (e.g., an environment containing nitrogen) for a significantly longer time compared to other similar alkali metal films without passivated surfaces, without significantly affecting their performance when ultimately used as part of an electrode (e.g., an anode) in a lithium-ion battery. Furthermore, the passivation of the alkali metal films 241 and 242 improves their performance when used as part of an electrode (e.g., an anode) in a lithium-ion battery.

[0099] Figure 8 A flowchart illustrating selected operations of a method 800 for forming an energy storage device via a laser ablation process according to one or more implementations of this disclosure is provided. It should also be noted that, although... Figure 8 Method 800 is described sequentially, but other process sequences, including one or more operations that have been omitted and / or added, and / or rearranged in another desired order, also fall within the scope of the implementations of this disclosure provided herein. Method 800 can be performed using any of the aforementioned flexible substrate transfer systems 100, 300, 400, and 500. Method 800 is similar to method 600, except that the lower surface 130L and upper surface 130U of the flexible substrate stack 130 are processed sequentially rather than simultaneously.

[0100] At operation 810, the flexible substrate stack 130 and the second flexible carrier film 120 are transported toward a laser lift-off unit, such as laser lift-off unit 200. The flexible substrate stack 130 may be exposed to a surface activation process as described prior to the alkali metal transfer process. At operation 820, the second alkali metal film 242 is contacted with one surface of the flexible substrate stack 130. For example, one surface of the alkali metal film 242 contacts the lower surface 130L of the flexible substrate stack 130. The laser lift-off process of operation 820 includes exposing the second flexible carrier film 120, on which the alkali metal film 242 is formed, to laser energy, such as laser energy provided by the second laser source assembly 201b. At operation 830, the second flexible carrier film 120 may be peeled off from the flexible substrate stack 130, for example, when the second flexible carrier film 120 is transported through Figure 3 When rollers 382 and 383 are shown. Subsequently, the second flexible carrier film 120 is conveyed to a corresponding pick-up hub, such as pick-up hub 126. At operation 840, the flexible substrate stack 130 having an alkali metal film 242 formed on the lower surface 130L and a first flexible carrier film 110 is conveyed toward a laser stripping unit, such as laser stripping unit 200. At operation 820, the first alkali metal film 241 is contacted with one surface of the flexible substrate stack 130. For example, one surface of the alkali metal film 241 contacts the upper surface 130U of the flexible substrate stack 130. The laser stripping process of operation 840 includes exposing the first flexible carrier film 110 having the alkali metal film 241 formed thereon to laser energy, such as laser energy provided by the first laser source assembly 201a. At operation 850, the first flexible carrier film 110 can be peeled off from the flexible substrate stack 130, for example, when the first flexible carrier film 110 is conveyed through Figure 3 As shown in rollers 386 and 387. At operation 860, the exposed alkali metal films 241 and 242 may optionally be exposed to a passivation process to form passivation films 750a-b as previously described. At operation 870, the alkali metal films 241 and 242 on the flexible substrate stack 130 are conveyed to the pick-up hub 136. The alkali metal films 241 and 242 on the flexible substrate stack 130 may be combined with a diaphragm before or during winding onto the pick-up hub 136 to further protect the alkali metal films.

[0101] Figure 9 A flowchart illustrating selected operations of another method 900 for forming an energy storage device via a laser ablation process according to one or more implementations of this disclosure is provided. It should also be noted that, although... Figure 9The method 900 illustrated herein is described sequentially, but other process sequences, including one or more operations that have been omitted and / or added, and / or rearranged in another desired order, also fall within the scope of the implementations of this disclosure provided herein. Method 900 can be performed using any of the aforementioned flexible substrate transfer systems 100, 300, 400, and 500. In method 900, the lower surface 130L and upper surface 130U of the flexible substrate stack 130 are processed sequentially, not simultaneously.

[0102] At operation 910, the flexible substrate stack 130, the first flexible carrier film 110, and the second flexible carrier film 120 are transported toward a laser lift-off unit, such as laser lift-off unit 200. The flexible substrate stack 130 may be exposed to a surface activation process as described prior to the alkali metal transfer process. At operation 920, the first alkali metal film 241 and the second alkali metal film 242 respectively contact the opposing surfaces of the flexible substrate stack 130. For example, one surface of the alkali metal film 242 contacts the lower surface 130L of the flexible substrate stack 130, and one surface of the alkali metal film 241 contacts the upper surface 130U of the flexible substrate stack 130. The laser lift-off process of operation 920 includes exposing the second flexible carrier film 120, on which the alkali metal film 242 is formed, to laser energy, such as laser energy provided by the second laser source assembly 201b. At operation 930, the second flexible carrier film 120 may be peeled off from the flexible substrate stack 130, for example, when the second flexible carrier film 120 is transported through Figure 4 When rollers 482 and 483 are shown. Subsequently, the second flexible carrier film 120 is conveyed to a corresponding pick-up hub, such as pick-up hub 126. At operation 940, the flexible substrate stack 130 having an alkali metal film 242 on its lower surface 130L and a first flexible carrier film 110 and an alkali metal film 241 on its upper surface 130U is conveyed toward a laser stripping unit, such as laser stripping unit 200. The laser stripping process of operation 940 includes exposing the first flexible carrier film 110 having the alkali metal film 241 formed thereon to laser energy, such as laser energy provided by the first laser source assembly 201a. At operation 950, the first flexible carrier film 110 can be peeled off from the flexible substrate stack 130, for example, when the first flexible carrier film 110 is conveyed through Figure 4When the roller 485 is shown. Subsequently, the first flexible carrier film 110 is conveyed to the corresponding pick-up hub, such as pick-up hub 116. At operation 960, the exposed alkali metal films 241, 242 may optionally be exposed to a passivation process to form passivation films 750a-b as described above. At operation 970, the alkali metal films 241, 242 on the flexible substrate stack 130 are conveyed to pick-up hub 136. The alkali metal films 241, 242 on the flexible substrate stack 130 may be combined with a diaphragm before or during winding onto pick-up hub 136 to further protect the alkali metal films.

[0103] Figure 10 A schematic diagram illustrating a flash assembly 1000 according to one or more implementations of the present disclosure is shown. The flash assembly 1000 may be used to replace at least one of a first laser source assembly 201a and a second laser source assembly 201b. The flash assembly 1000 may include a flash array having a plurality of radiation-emitting lamps (e.g., xenon, argon, or krypton discharge lamps). The flash assembly 1000 includes an energy source 1010 for emitting high-energy pulses, an elliptical reflector 1020 covering the energy source 1010 and focusing the energy into a narrow line, and an optical assembly 1030.

[0104] An energy source 1010 (which may be a light source) is configured to deliver electromagnetic energy during the stripping process. The energy source 1010 may include a radiation-emitting lamp, such as a xenon, argon, or krypton discharge lamp. The energy source 1010 is configured to deliver energy pulses with pulse widths ranging from about 1 microsecond to about 100 milliseconds. These energy pulses induce near-instantaneous heating of the film surface, but with low total power, thereby reducing substrate heating.

[0105] Energy source 1010 is configured to generate energy 1012 and introduce it into optical component 1030, which shapes the energy into a desired form for delivery to a substrate (e.g., a first flexible carrier film 110). Optical component 1030 generally includes lenses, filters, mirrors, etc., and is configured to focus, polarize, depolarize, filter, or adjust the coherence of the energy generated by energy source 1010 to deliver a uniform energy column to the substrate. In one or more implementations that can be combined with other implementations, optical component 1030 includes a broadband filter or grating configured, for example, to reflect radiation with wavelengths less than 750 nm and transmit radiation with wavelengths greater than 750 nm.

[0106] The previously described implementations of this disclosure have numerous advantages. However, this disclosure does not require that all advantageous features and benefits be incorporated into every implementation of this disclosure. The transfer process and system described herein enable roll-to-roll laser lift-off processing and offer one or more of the following advantages: patterned lithium transfer, low-pressure calendered lithium transfer, room-temperature lithium transfer, lithium surface modification in a controlled environment, faster transfer rates, reuse of the flexible plastic support substrate, elimination of the need to cut rolls for patterned transfer, simplified transfer tool architecture, and small tool footprint. This transfer process is safe and industrially scalable for high-volume manufacturing. Furthermore, the ability to transfer lithium in a controlled environment and the potential for reusing plastic substrate rolls provide a low-risk commercialization path.

[0107] In the abstract, the following detailed description, the appended claims, and the accompanying drawings, specific features (including method steps) of this disclosure are referenced. It should be understood that this disclosure as described herein includes all possible combinations of these specific features. For example, where a specific feature is disclosed in the context of a particular aspect, implementation, or claim of this disclosure, that feature may also be used, where possible, in combination with other specific aspects and implementations of this disclosure and with the disclosure as a whole.

[0108] This document uses the terms “comprising,” “including,” and “having,” and their grammatical equivalents, to indicate that other parts, components, operations, etc., may optionally be present. For example, an article that includes (or “comprising”) parts A, B, and C may consist of (i.e., contain only) parts A, B, and C, or may contain not only parts A, B, and C, but also one or more other parts. Furthermore, whenever the transitional phrase “comprising” or its grammatical equivalent is used before a part, element, or group of elements, it should be understood that the transitional phrases “basically composed of,” “composed of,” “selected from,” or “is” may also be used before that part, element, or group of elements, and vice versa.

[0109] In this specification, when a method comprising two or more qualified operations is referenced, these qualified operations may be performed in any order or simultaneously (unless the context precludes such a possibility), and the method may include one or more other operations performed before any qualified operation, between two qualified operations, or after all qualified operations (unless the context precludes such a possibility).

[0110] In this specification, when a range is given as "(first number) to (second number)" or "(first number) - (second number)", it means a range with the lower limit of the first number and the upper limit of the second number. For example, 25 to 100 mm means a range with the lower limit of 25 mm and the upper limit of 100 mm.

[0111] The implementations and all functional operations described herein can be implemented in digital electronic circuits, or in computer software, firmware, or hardware, including the structural devices and their equivalents disclosed herein, or combinations thereof. The 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 executing or controlling the operation of a data processing device, such as a programmable processor, computer, or multiple processors or computers.

[0112] The process and logic flow described herein can be executed by one or more programmable processors executing one or more computer programs to perform functions by manipulating input data and generating outputs. The process and logic flow can also be executed by dedicated logic circuits, and the device can also be implemented as dedicated logic circuits, such as FPGAs (Field-Programmable Gate Arrays) or ASICs (Application-Specific Integrated Circuits).

[0113] The term "data processing device" encompasses all devices, apparatuses, and machines used for processing data, including, by way of example, programmable processors, computers, or multiple processors or computers. In addition to hardware, the device may include code that generates an execution environment for the computer program in question, such as code constituting processor firmware, a protocol stack, a database management system, an operating system, or a combination of one or more of these. Processors suitable for executing computer programs include, by way of example, general-purpose and special-purpose microprocessors, as well as any one or more processors of any type of digital computer.

[0114] Computer-readable media suitable for storing computer program instructions and data include all forms of non-volatile memory, media, and storage devices, including exemplary semiconductor storage devices such as EPROM, EEPROM, and flash memory devices; magnetic disks, such as internal hard disks or removable disks; magneto-optical disks; and CD-ROM and DVD-ROM disks. The processor and memory may be supplemented by or incorporated into dedicated logic circuitry.

[0115] When introducing an element of this disclosure or an exemplary aspect or implementation thereof, the articles “a,” “an,” “the,” and “the” are intended to indicate the presence of one or more elements.

[0116] While the foregoing describes an implementation of this disclosure, other and further implementations of this disclosure may be designed without departing from its basic scope, and the scope thereof is determined by the following claims.

Claims

1. A flexible substrate processing system, comprising: The first supply hub is used to supply a flexible carrier membrane on which an alkali metal film is formed; The second supply hub is used to supply flexible substrate film stacks; A first pickup hub is used to collect the flexible carrier film after the alkali metal film has been transferred to the flexible substrate film stack; The second pickup hub is used to collect the flexible substrate film stack on which the alkali metal film is formed. as well as A laser stripping unit is positioned downstream of the first supply hub and the second supply hub and upstream of the first pickup hub and the second pickup hub. The laser stripping unit includes: A laser source is configured to generate laser energy, which is directed toward a first surface of the flexible carrier film. as well as An optical scanner is configured to direct the laser energy toward the first surface of the flexible carrier film.

2. The flexible substrate processing system as described in claim 1, further comprising: A pair of rollers, positioned downstream of the first and second supply hubs and upstream of the laser source, are configured to contact the alkali metal film with the flexible substrate film stack.

3. The flexible substrate processing system of claim 2, wherein the pair of rollers includes at least one clamping roller.

4. The flexible substrate processing system of claim 2, wherein the pair of rollers includes at least one calendering roller.

5. The flexible substrate processing system of claim 1, wherein the laser source is selected from infrared (IR) fiber laser, ultraviolet (UV) laser or green laser.

6. The flexible substrate processing system of claim 1, wherein the optical scanner is a single or multi-axis large-angle galvanometer optical scanner.

7. The flexible substrate processing system of claim 1, wherein the optical scanner is a polygon scanner, an electro-optic scanner, an acousto-optic device, or a combination thereof.

8. The flexible substrate processing system of claim 1, further comprising: A passivation unit, located downstream of the laser lift-off unit and upstream of the second pick-up hub, is positioned to passivate the alkali metal film formed on the flexible substrate film stack.

9. The flexible substrate processing system of claim 1, further comprising: An online slitting assembly, including blades, is used to cut the flexible carrier membrane, and the online slitting assembly is positioned downstream of the laser ablation unit and upstream of the first pickup hub.

10. A flexible substrate processing system for forming an energy storage device, comprising: The laser ablation unit includes: A laser source is configured to generate laser energy, which is directed toward a first surface of a flexible carrier film; and An optical scanner is configured to direct the laser energy toward the first surface of the flexible carrier film; and The system controller is configured to cause the laser ablation unit to perform a process, the process including: A stack of flexible carrier films, including a flexible carrier film with an alkali metal film formed on it, is transported from the supply hub toward the pick-up hub. The flexible carrier film stack is brought into contact with the flexible substrate film stack, wherein the alkali metal film contacts the flexible substrate film stack; Exposing the first surface of the stacked flexible carrier films to the laser energy to separate the flexible carrier films from the alkali metal films; and The flexible carrier film is removed from the flexible substrate film stack.

11. The flexible substrate processing system of claim 10, wherein the laser source is selected from infrared (IR) fiber laser, ultraviolet (UV) laser or green laser.

12. The flexible substrate processing system of claim 10, wherein the optical scanner is a single- or multi-axis large-angle galvanometer optical scanner.

13. The flexible substrate processing system of claim 10, further comprising: A pair of rollers, positioned upstream of the laser source, bring the flexible carrier film stack into contact with the flexible substrate film stack.

14. The flexible substrate processing system of claim 13, wherein the pair of rollers includes at least one clamping roller.

15. The flexible substrate processing system of claim 13, wherein the pair of rollers includes at least one calendering roller.

16. A method for forming a membrane stack for an energy storage device, comprising: The flexible carrier membrane stack, including a flexible carrier membrane with an alkali metal film formed on it, is transported from the supply hub toward the pick-up hub. The flexible carrier film stack is brought into contact with the flexible substrate film stack, wherein the alkali metal film contacts the flexible substrate film stack; The first surface of the stacked flexible carrier films is exposed to laser energy to separate the flexible carrier films from the alkali metal films. as well as The flexible carrier film is removed from the flexible substrate film stack.

17. The method of claim 16, wherein exposing the first surface of the stacked flexible carrier films to laser energy to separate the flexible carrier films from the alkali metal films comprises patterning the alkali metal films by exposing portions of the alkali metal films to the laser energy.

18. The method of claim 17, wherein the laser energy is directed through the back side of the flexible carrier membrane.

19. The method of claim 17, wherein the first surface of the flexible carrier film stack is exposed to laser energy to generate a void volume between the alkali metal film and the flexible carrier film stack.

20. The method of claim 17, wherein the flexible carrier film stack further includes a release layer disposed between the flexible carrier film and the alkali metal film, the release layer being capable of photoinduced depolymerization.

Images