Multilane transfer system for pre-lithiation

Abstract

Embodiments of the present disclosure relate to a system, device and method related to thin film lithium energy storage devices, which typically employ a lithium deposition process. The system is a flexible substrate processing system including a pickup hub, the pickup hub configured to rotate and assist in conveying a flexible substrate through an interior volume of a calendering unit, the calendering unit comprising a first calender roller and a second calender roller, the first calender roller and the second calender roller configured to rotate, apply pressure, and allow the flexible substrate to pass between the first calender roller and the second calender roller. The system further includes a first flexible die, the first flexible die configured to attach to the first calender roller.

Description

MULTILANE TRANSFER SYSTEM FOR PRE-LITHIATIONBACKGROUNDField

[0001] The present disclosure generally relates to systems and methods for transferring multiple lanes of lithium onto a substrate in a roll-to-roll application, such as depositing a thin film of lithium of different sizes and widths over the substrate used in a roll-to-roll application. Description of the Related Art

[0002] Rechargeable electrochemical storage systems are increasing in importance for many fields of everyday life. High-capacity energy storage devices, such as lithium-ion (Li- ion) batteries and capacitors, are used in a growing number of applications, including portable electronics, medical, transportation, grid-connected large energy storage, renewable energy storage, and uninterruptible power supply (UPS). In each of these applications, the charge / discharge time and capacity of energy storage devices are fundamental parameters. In addition, the size, weight, and / or cost of such energy' storage devices are also fundamental parameters. Further, low internal resistance is integral for high performance. The lower the resistance, the less restriction the energy storage device encounters in delivering electrical energy. For example, in the case of a battery, internal resistance affects performance by reducing the total amount of useful energy' stored by the battery as well as the ability of the battery' to deliver high current.

[0003] One method for manufacturing energy storage devices is roll-to-roll processing. An effective roll-to-roll deposition process not only provides a high deposition rate, but also provides a fdm surface, which lacks small-scale roughness, contains minimal defects, and is flat, for example, lacks large scale topography. In addition, an effective roll-to-roll deposition process also provides consistent deposition results or “repeatability.'’

[0004] Thin fdm lithium energy storage devices typically employ a lithium deposition process where a thin fdm of lithium is deposited on or over a substrate or web before being laminated with an anode. Roll-to-roll processing often involves a certain roll width to be economical, even if the targeted roll width is smaller. The rolls coated with lithium may be resized to achieve the targeted roll width or size.

[0005] Therefore, there is a need for improved systems and methods for depositing a thin fdm of lithium of different sizes and widths over a substrate.SUMMARY

[0006] The present disclosure generally relates to systems and methods for transferring multiple lanes of lithium onto a substrate in a roll-to-roll application, such as depositing a thin film of lithium of different sizes and widths over the substrate used in a roll-to-roll application.

[0007] In one embodiment, a system is provided. The system is a flexible substrate processing system including a pickup hub, the pickup hub configured to rotate and assist in conveying a flexible substrate through an interior volume of a calendering unit, the calendering unit comprising a first calender roller and a second calender roller, the first calender roller and the second calender roller configured to rotate, apply pressure, and allow the flexible substrate to pass between the first calender roller and the second calender roller, a first flexible die, the first flexible die configured to attach to the first calender roller.

[0008] In another embodiment, a device is provided. The device includes a first calender roller, the first calender roller including an outer surface, a second calender roller, the second calender roller including an outer surface, a first flexible die, the first flexible die including a plurality of ridges and a plurality of recesses.

[0009] In yet another embodiment, a method is provided. The method including conveying a flexible substrate, a first flexible carrier, and a second flexible carrier towards a calendering unit, the calendering unit includes two calender rollers, transferring a first alkali film from the first flexible carrier and a second lithium film from the second flexible carrier to the flexible substrate by pressure applied by calender rollers, at least one of the calender rollers including a flexible die, and peeling away the first flexible carrier and the second flexible carrier from the flexible substrate.BRIEF DESCRIPTION OF THE DRAWINGS

[0010] So that the manner in which the above-recited features of the present disclosure can be understood in detail, a more particular description of the aspects, briefly summarized above, may be had by reference to implementations, some of which are illustrated in the appended drawings. It is to be noted, however, that the appended drawings illustrate only typical implementations of this disclosure and are therefore not to be considered limiting of its scope, for the disclosure may admit to other equally effective implementations.

[0011] Figure 1 shows a side schematic view of a substrate processing system in accordance with one or more implementations of the present disclosure.

[0012] Figure 2A is a perspective schematic view of a calender roller with a flexible die including a first pattern in accordance with one or more implementations of the present disclosure.

[0013] Figure 2B is a cross sectional view along line B'-B’ of a calender roller with a flexible die including a first pattern in accordance with one or more implementations of the present disclosure.

[0014] Figure 3A is a perspective schematic view7of a calender roller with a flexible die including a second pattern and a longitudinal axis in accordance with one or more implementations of the present disclosure.

[0015] Figure 3B is a cross sectional view along line D’-D’ of a calender roller with a flexible die including a second pattern in accordance w ith one or more implementations of the present disclosure.

[0016] Figure 3C is a cross sectional view along line C’-C’ of a calender roller with a flexible die including a second pattern in accordance with one or more implementations of the present disclosure.

[0017] Figure 4A is a top schematic view7of a flexible die including a pattern for multiple lanes in accordance with one or more implementations of the present disclosure.

[0018] Figure 4B is a top schematic view of a flexible die including a pattern for multiple lanes and skip transfers in accordance with one or more implementations of the present disclosure.

[0019] Figure 4C is a side schematic view7of a flexible die including a pattern for multiple lanes in accordance with one or more implementations of the present disclosure.

[0020] Figure 5 is a process flow diagram of a method of transferring lithium films onto a flexible substrate where the lithium film is patterned during processing in accordance with one or more implementations of the present disclosure.

[0021] Figure 6A is a schematic view of a calendering unit during processing in accordance with one or more implementations of the present disclosure.

[0022] Figure 6B is a schematic top view7of a flexible substrate including a patterned lithium film after processing using a calendering unit as described in accordance with one or more implementations of the present disclosure.

[0023] Figure 6C is a schematic side view of a flexible substrate including a patterned lithium film after processing using a calendering unit as described in accordance with one or more implementations of the present disclosure

[0024] To facilitate understanding, identical reference numerals have been used, where possible, to designate identical elements that are common to the figures. It is contemplated that elements and features of one embodiment may be beneficially incorporated in other embodiments w ithout further recitation.DETAILED DESCRIPTION

[0025] The present disclosure generally relates to systems and methods for transferring multiple lanes of lithium onto a substrate in a roll-to-roll application, such as depositing a thin film of lithium of different sizes and widths over the substrate used in a roll-to-roll application.

[0026] Soft metals, such as lithium metal can function as electrode materials in electrochemical cells and batteries. Bulk lithium can be purchased commercially as a solid suspension in oil or as a foil. It can also be deposited on to a substrate using a variety of techniques, such as vapor deposition, vacuum deposition, or molecular beam epitaxy techniques. In order to fit the dimensions for a particular electrochemical application, the bulk lithium may involve depositing the lithium in a specific size onto a substrate during processing in a roll-to-roll application.

[0027] In one or more implementations, which can be combined with other implementations, substrate independent direct transfer (SIDT) is used to transfer multiple lanes or sizes of lithium onto a substrate by use of a patterned calendering unit. For example, a lithium film can be transferred from a flexible carrier (e.g.. a polymer-based carrier) to a flexible substrate (e g., a flexible copper substrate) by having the flexible carrier and the flexible substrate pass through a calendering unit and then peeling away the flexible carrier. The calendering unit includes two calender rollers, each roller includes ridges and recesses, which control the size and shape of the lithium transferred from the flexible carrier to the flexible substrate. For example, the calender rollers may include a flexible die attached to the outer surface of each calender roller. The flexible die includes multiple lanes of ridges, multiple ridges sized for a skip transfer pattern, or combinations thereof. Between the ridges, recesses form on the flexible die. The ridges and recesses provide a pattern on the flexible die. The ridges provide pressure and a point of contact when the flexible carrier and the flexible substrate pass through the calendering unit. Once the flexible carrier is peeled away, lithium is deposited onto the substrate where the ridges were patterned on the flexible die. Lithium remains on the flexible carrier where the recesses were patterned on the flexible die. The flexible substrate may then go through further processing. For example, a cutting step to size the substrate based on the patterned lithium on the substrate.

[0028] It is noted that while the particular substrate on which some implementations described herein can be practiced is not limited, it is particularly beneficial to practice the implementations on flexible substrates, including for example, web-based substrates, panels and discrete sheets. The flexible substrate can also be in the form of a foil, a polymer film, or a thin plate.

[0029] It is also noted here that a flexible substrate or web as used within the implementations described herein can typically be charactenzed in that it is bendable. The term “web” can be synonymously used to the term “strip,” the term “flexible substrate,” or the term “flexible conductive substrate.” For example, the web as described in implementations herein can be a polymer material.

[0030] It is further noted that the methods and systems described may be used in forming single-sided electrode structures and double-sided electrode structures.

[0031] Figure 1 shows a side cross-sectional view7of a processing system 100 incorporating a calendering unit 140. The processing system 100 includes equipment for transferring lithium films on a first flexible carrier 110 and a second flexible carrier 120 to each side of a flexible substrate 130, so that the flexible substrate 130 with the lithium films can be used as an electrode (e.g., anode) in a lithium-ion battery. The processing system 100 includes a calendering unit 140 to transfer the lithium films on the flexible carriers (e.g., the first flexible carrier 110 and the second flexible carrier 120) to the flexible substrate 130. The calendering unit 140 includes two calendering rollers 141 (e.g., a first calendering roller 141a and a second calendering roller 141b). The calendering unit 140 further includes a first flexible die 144a and a second flexible die 144b. The first flexible die 144a is secured to an outer surface 148 of the first calendering roller 141a. The second flexible die 144b is secured to the outer surface 148 of the second calendering roller 141b. Additional detail on the each flexible die 144 is described in reference to Figure 2A, Figure 2B, Figure 3A, Figure 3B, Figure 3C, Figure 4A, Figure 4B, and Figure 4C below.

[0032] The processing system 100 includes a first flexible carrier supply hub 115. A supply roll 111 of the first flexible carrier 110 is positioned on the first flexible carrier supply hub 115. In some embodiments, the first flexible carrier 110 can be formed of a polymer material, such as such as polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polyimide (PI), or combinations thereof. A lithium film (not shown in Figure 1) is positioned on the low er side 110U of the first flexible carrier 110, so that this lithium film faces an upper surface 130U of the flexible substrate 130 as the first flexible carrier 110 and the flexible substrate 130 are conveyed through the calendering unit 140. The upper surface 130U of the flexible substrate 130 is on an opposite side relative to a lower surface 130L of the flexible substrate 130. The upper surface 130U is also referred to as the first surface or the first side of the flexible substrate 130 while the lower surface is also referred to as the second surface or the second side of the flexible substrate 130.

[0033] The processing system 100 includes a second flexible carrier supply hub 125. A supply roll 121 of the second flexible carrier 120 is positioned on the second flexible carrier supply hub 125. In some embodiments, the second flexible carrier 120 can be formed of a same material (e.g., PET) as the first flexible carrier 110. A lithium film (not shown in Figure 1) is positioned on the upper side 120U of the second flexible carrier 120. so that this lithium film faces the lower surface 130L of the flexible substrate 130 as the second flexible carrier 120 and the flexible substrate 130 are conveyed through the calendering unit 140.

[0034] In some embodiments, the lithium films on the first flexible carrier 110 and the second flexible carrier 120 can be formed of lithium metal, other alkali metals, or an alloy including an alkali metal.

[0035] The processing system 100 includes a flexible substrate supply hub 135. A supply roll 131 of the flexible substrate 130 is positioned on the flexible substrate supply hub 135. In some embodiments, the flexible substrate 130 can be or include one or more of copper, graphite, silicon, silicon graphite, silicon oxide graphite, silicon, metalized plastic, or other materials.

[0036] The processing system 100 further includes the calendering unit 140. The calendering unit 140 includes two calender rollers 141, a first calender roller 141a and a second calender roller 141b. Referring to FIG. 2A-B, each calender roller 141 includes an outer surface 148. A flexible die 144 is secured to the outer surface 148 of each calender roller 141. For example, the first flexible die 144a is secured to an outer surface 148 of the first calender roller 141a, and the second flexible die 144b is secured to the outer surface 148 of the second calender roller 141b. The flexible die may be secured by adhesive, magnets or tape. The flexible die 144 may be formed of metal or plastic material. In some embodiments, the outer surface 148 of the calender rollers 141 are patterned (e.g.. the outer surfaces 148 of the calender rollers 141 do not include a flexible die 144). In other embodiments, the flexible die 144 may be machined directly onto the outer surface 148 of the calender rollers 141. Each flexible die 144 includes ridges 147 and recesses 146, as seen in Figure 2B.

[0037] The first flexible carrier 110, the second flexible carrier 120. and the flexible substrate 130 are arranged to be conveyed along a path that extends between the calendering rollers 141. The flexible substrate 130 is positioned between the first flexible carrier 110 and the second flexible carrier 120 when the first flexible carrier 110, the second flexible carrier 120. and the flexible substrate 130 are conveyed between the calender rollers 141 (e.g.. the first calender roller 141a and the second calender roller 141b). The calender rollers 141 exert a high amount of pressure on the first flexible carrier 110, the second flexible carrier 120, andthe flexible substrate 130 where the ridges 147 are patterned on the flexible die 144. The pressure causes the lithium film on the first flexible carrier 110 and the second flexible carrier 120 to be transferred to the flexible substrate 130. The lithium is transferred where there are ridges 147 present on the outer surface 148 of the calendering rollers 141. In some embodiments, a release layer is disposed on the first flexible carrier 110 and the second flexible carrier 120 between the corresponding flexible carrier (e.g.. the first flexible earner 110 and the second flexible carrier 120) and the lithium film on that flexible carrier. In some embodiments, the release layer can be formed of siloxane.

[0038] The processing system 100 includes a first flexible carrier pickup hub 116. A pickup roll 112 of the first flexible carrier 110 is positioned on the first flexible carrier pickup hub 116. Residual lithium film remains on the first flexible carrier 110 when the first flexible carrier 110 is wound onto the first flexible carrier pickup hub 116, because the lithium film previously on the first flexible carrier 110 is transferred onto the flexible substrate 130 by the calendering unit 140 according to the pattern of ridges 147 and recesses 146 disposed on the flexible die 144 secured around the calender rollers 141.

[0039] The processing system 100 includes a second flexible carrier pickup hub 126. A pickup roll 122 of the second flexible carrier 120 is positioned on the second flexible carrier pickup hub 126. Residual lithium film remains on the second flexible carrier 120 when the second flexible carrier 120 is wound onto the second flexible carrier pickup hub 126, because the lithium film previously on the second flexible carrier 120 is transferred onto the flexible substrate 130 by the calendering unit 140 according to the pattern of ridges 147 and recesses 146 disposed on the flexible die 144 secured around the calender rollers 141.

[0040] The processing system 100 includes a flexible substrate pickup hub 136. A pickup roll 132 of the flexible substrate 130 is positioned on the flexible substrate pickup hub 136. The flexible substrate 130 includes a patterned lithium film on each of the upper surface 130U and the lower surface 130L of the flexible substrate 130. The pattern of the lithium film is determined by the ridges 147 and recesses 146 disposed on the flexible die 144 that is attached to the calender roller 141 in the calendering unit 140. These lithium films are transferred from the first flexible carrier 110 and the second flexible carrier 120 onto the flexible substrate 130 by the calendering unit 140.

[0041] The processing system 100 further includes a plurality of rollers 181-188. In some embodiments, each of the rollers 181 -188 can be passive rollers. The rollers 181-188 can assist in applying proper tension to and assist in changing the direction of the flexible carriers (e.g., the first flexible carrier 110 and the second flexible carrier 120) and the flexible substrate 130during the movement of each of the flexible carriers (e.g., the first flexible carrier 110 and the second flexible carrier 120) and the flexible substrate 130 through the different portions of the processing system 100. Some of the rollers 181-188 can also assist in moving the flexible carriers (e.g., the first flexible carrier 110 and the second flexible carrier 120) closer to or further away from the flexible substrate 130. For example, the second roller 182 and third roller 183 assist in bringing the flexible carriers (e.g., the first flexible carrier 110 and the second flexible carrier 120) into contact with the flexible substrate 130 before the flexible carriers (e.g., the first flexible carrier 110 and the second flexible carrier 120) and the flexible substrate 130 are conveyed through the calendering unit 140. Additionally, the fourth roller 184 and fifth roller 185 provide a location at which tension can be applied to the flexible carriers (e.g., the first flexible carrier 110 and the second flexible carrier 120) to peel these flexible carriers (e.g., the first flexible carrier 110 and the second flexible carrier 120) away from the flexible substrate 130. In some embodiments, one or more of the rollers 181-188 can instead be a bar, such as metal bar, that can apply tension to the flexible carriers (e.g., the first flexible carrier 110 and the second flexible carrier 120) or the flexible substrate 130 during the movement of the flexible carriers (e g., the first flexible carrier 110 and the second flexible carrier 120) or flexible substrate 130.

[0042] The processing system 100 can further include actuators (not shown) configured to rotate each of the hubs 115. 116, 125, 126, 135, 136, so that the flexible earners (e.g., the first flexible earner 110 and the second flexible carrier 120) and the flexible substrate 130 can be conveyed from the corresponding supply hub 115, 125, 135, through the calendering unit 140, and to the corresponding pick hub 116, 126, 136. The processing system 100 can further include one or more actuators (not shown) to rotate the calender rollers 141 of the calendering unit 140. The rotational speed of the actuators can be adjusted to control the speed at which the flexible substrate 130 and flexible carriers (e.g., the first flexible carrier 110 and the second flexible carrier 120) are conveyed through the processing system 100.

[0043] In the processing system 100, the flexible substrate 130 is conveyed along a path 160 or travel direction from the supply roll 131 that is supported by the supply hub 135, past the first roller 181, between the second roller 182 and third roller 183, between the calender rollers 141, between the fourth roller 184 and fifth roller 185, past the eighth roller 188, and to the pickup roll 132 around the pickup hub 136. The pickup hub 136 is configured to rotate and assist in conveying the flexible substrate 130 through the processing system 100. Similarly, the pickup hubs 116, 126 are configured to rotate and assist in conveying the flexible carriers along paths between the supply hubs 1 15, 125 and the pickup hubs 116, 126.

[0044] The processing system 100 can also include a controller 105 for controlling processes performed by the processing system 100. The controller 105 can be any type of controller used in an industrial setting, such as a programmable logic controller (PLC). The controller 105 includes a processor 107, a memory 106, and input / output (I / O) circuits 108. The controller 105 can further include one or more of the following components (not shown), such as one or more power supplies, clocks, communication components (e.g., network interface card), and user interfaces typically found in controllers for semiconductor equipment.

[0045] The processor 107 is configured to execute various programs stored in the memory' 106, such as a program configured to execute the method 500 described below in reference to Figure 5. During execution of these programs, the controller 105 can communicate to I / O devices through the I / O circuits 108. For example, during execution of these programs and communication through the I / O circuits 108, the controller 105 can control outputs (e.g., the actuators connected to the different hubs and the calendering unit 140). The memory 106 can further include various operational settings used to control the processing system 100. For example, the settings can include speed settings for the actuators connected to the hubs.

[0046] Figure 2A is a perspective schematic view of a calender roller 141 (e.g., a first calender roller 141a) with a flexible die 144 (e.g., a first flexible die 144a) including a first pattern. Figure 2B is a cross sectional view along line B -B’ of a calender roller 141 (e.g. a first calender roller 141a) with a flexible die 144 (e.g. a first flexible die 144a) that includes the first pattern. The pattern depicted in Figures 2A-2B is exemplary, the flexible die 144 may include any pattern.

[0047] As shown in Figure 2A, the flexible die 144 surrounds an outer surface 148 of the calender roller 141. The calender roller 141 may include hardened steel with an optional chrome plating and an optional additional surface coating. The flexible die 144 is secured to the calender roller 141 using any suitable method, for example, tape, an adhesive, or with magnets. In other embodiments, the flexible die 144 may be sized to secure to the calender roller 141 (e.g., the flexible die 144 secures to the calender roller 141 without the use of additional adhesives). The flexible die 144 may be formed of metal, plastic material, or any other material suitable to conform to the outer surface 148 of the calender roller 141 and withstand the pressure required during processing of the flexible substrate 130. For example, the metal is stainless steel. The calender roller 141 includes a longitudinal axis 156. As show n in Figure 2A and Figure 2B, the flexible die 144 is patterned with a first pattern including with ridges 147 and recesses 146. As shown in Figure 2A the ridges 147 and recesses 146 are patterned parallel to the longitudinal axis 156. Along the end 162 of the flexible die 144 arecess 146 is patterned. The pattern of ridges 147 and recesses 146 can be a variety of sizes or shapes. For example, as shown in Figure 2A. the flexible die 144 includes ridges 147 to pattern lithium in a skip transfer pattern 152 onto the flexible substrate 130. The skip transfer pattern 152 may be rectangular or square in shape. The skip transfer pattern 152 may include any width or length to achieve the desired shape and size of lithium patterning. The ridges 147 include a height of at least about 2 mm to about 10 cm.

[0048] Figure 3 A is a perspective schematic view of a calender roller 141 (e.g. a first calender roller 141a) with a flexible die 144 including a second pattern. Figure 3B is a cross sectional view along section line D’-D’ of a calender roller 141 (e g., a first calender roller 141a) with a flexible die 144 including a second pattern. Figure 3C is a cross sectional view along line C’-C’ seen in Figure 3A of the calender roller 141 and the flexible die 144 including a second pattern. The pattern depicted in Figures 3A-3C is exemplar}', the flexible die 144 may include any pattern.

[0049] As show in Figure 3A, the flexible die 144 surrounds an outer surface 148 of the calender roller 141. The calender roller includes a longitudinal axis 156. The flexible die 144 includes a second pattern where the ridges 147 and the recesses 146 are patterned perpendicular to the longitudinal axis 156. In the embodiment shown in Figures 3A-3C, the ridges 147 and recesses 146 wrap around the calender roller 141 to pattern lithium in multiple lanes 150. The multiple lanes 150 are rectangular in shape and may include a width of greater than 20 cm to about 2 mm. The recesses 146 of the second pattern may include a width of about 5 cm to the full length of a tool. As shown in Figure 3B, the second pattern on the flexible die 144 is shown along section line D’-D. ’ As shown in Figure 3C, the second pattern on the flexible die 144 is shown along section line C’-C.’ The ridges 147 and recesses 146 are visible along section line C’-C.’

[0050] In some embodiments, the outer surface 148 of the calender rollers 141 are patterned with ridges 147 and recesses 146 (e.g., the outer surfaces 148 of the calender rollers 141 do not include a flexible die 144. The ridges 147 and recesses 146 are machined onto the calender roller 141).

[0051] Figure 4A is a top schematic view of a flexible die 144 including a pattern for multiple lanes 150. Figure 4B is a top schematic view' of a flexible die including a pattern for multiple lanes 150 and skip transfer patterns 152. Figure 4C is a side schematic view of a flexible die 144 including a pattern of multiple lanes 150. Ridges 147 create the multiple lanes 150 and skip transfer patterns 152. Recesses 146 surround the multiple lanes 150 and the skip transfer patterns 152. The size and shape of the multiple lanes 150 and skip transfer patterns152 are customizable based on the desired size of the lithium transfer. For example, each lane in the multiple lanes 150 may be the same size. In another embodiment, at least one lane of the multiple lanes 150 may be a different size. For example, on a 800 mm web with multiple lanes 150, there may be three 250 mm lanes 150 separated by a 5 cm recess 146. For example, on an 800 mm web with a skip transfer pattern, there may be a 5 cm recess 146 between each 20 cm ridge 147.

[0052] Figure 5 is a process flow diagram of a method 500 of transferring lithium films onto a flexible substrate 130 where the lithium films 154 are patterned during processing. Although described in reference to the processing system 100 of Figure 1, the method 500 may be performed using other processing systems. Figure 6A illustrates an enlarged view of the flexible substrate 130 and the calendering unit 140 during processing using the processing system 100. Figure 6B and Figure 6C illustrate the lithium film 154 transferred onto the flexible substrate 130 at the end of processing using the processing system 100.

[0053] At operation 510, the processing system 100 conveys the flexible substrate 130 and a first flexible carrier 110 and a second flexible carrier 120 towards the calendering unit 140 from the corresponding supply hubs 115, 125, and 135.

[0054] At operation 520, the lithium films 154 are transferred from the first flexible carrier 110 and the second flexible carrier 120 to the flexible substrate 130 by the calendering unit 140. The calendering unit 140 includes two calender rollers 141a-b. Each calender roller 141a-b includes a flexible die 144a-b respectively. Each flexible die 144a-b is patterned with ridges 147 and recesses 146 to provide a pattern for the lithium films 154 to be transferred onto the flexible substrate 130. In one or more implementations, the flexible die 144a includes a pattern that is different from the pattern of the flexible die 144b. In one or more implementations, the flexible die 144a and the flexible die 144b include the same pattern. In one or more implementations, the first calender roller 141a includes a flexible die and the second calender roller 141b does not include a flexible die. The ridges 147 provide a surface for pressure to be applied to the first flexible carrier 110, the second flexible carrier 120, and the flexible substrate 130, so that lithium films 154 can be transferred from the first flexible carrier 110 and second flexible carrier 120 to the flexible substrate 130. The first lithium film 154a is transferred from the first flexible carrier 110 to the upper surface 130U of the flexible substrate 130 by the calendering unit 140. The second lithium film 154b is transferred from the second flexible carrier 120 to the lower surface 130L of the flexible substrate 130 by the calendering unit 140.

[0055] At operation 530. the first flexible carrier 110 and the second flexible carrier 120 are peeled away from the flexible substrate 130 as the first flexible carrier 110 and the second flexible carrier 120 are conveyed past the fourth roller 184 and the fifth roller 185 as shown in Figure 1. In some embodiments, a release layer is disposed on the first flexible carrier 110 and the second flexible carrier 120 to aid in the release of the lithium films 154. The first flexible carrier 110 and the second flexible carrier 120 is then conveyed to the respective pickup hub 116, 126. As shown in Figure 6B, the flexible substrate 130 is patterned with a lithium film 154 according to the pattern included on the flexible die 144. In this example, multiple lanes of lithium film 154 that include different widths of lithium film 154 were patterned onto the flexible substrate 130. In other embodiments, the flexible substrate may be patterned with multiple lanes of lithium film 154 of the same size, or the flexible substrate 130 may include skip transfer pattern 152. As shown in Figure 6C, a side view- of the flexible substrate 130 is shown. The first lithium film 154a is patterned on upper surface 130U of the flexible substrate 130. and the second lithium film 154b is patterned on the lo er surface 130L of the flexible substrate 130. In other embodiments, only one side of the flexible substrate 130 includes a transferred lithium film 154. The flexible substrate 130, which includes the lithium films 154, is conveyed to the pickup hub 136.

[0056] Overall, the various embodiments of the present disclosure relate to thin film lithium energy storage devices, which typically employ a lithium deposition process where a thin film of lithium is deposited on or over a substrate or web before being laminated with an anode. Roll-to-roll processing often involves a certain roll width to be economical, even if the targeted roll width is smaller. The rolls coated with lithium may be resized to achieve the targeted roll width or size. In particular, transferring multiple lanes of lithium onto a substrate in a roll-to-roll application, such as depositing a thin film of lithium of different sizes and widths over the substrate used in a roll-to-roll application.

[0057] In the Summary and in the Detailed Description, and the Claims, and in the accompanying drawings, reference is made to particular features (including method operations) of the present disclosure. It is to be understood that the disclosure in this specification includes all possible combinations of such particular features. For example, where a particular feature is disclosed in the context of a particular aspect, implementation, or example of the present disclosure, or a particular claim, that feature can also be used, to the extent possible in combination with and / or in the context of other particular aspects and implementations of the present disclosure, and in the present disclosure generally.

[0058] Other tools capable of performing high rate deposition processes may also be adapted to benefit from the implementations described. In addition, any system enabling the deposition processes described can be used to advantage. The apparatus description described is illustrative and should not be construed or interpreted as limiting the scope of the implementations described. It should also be understood that although described as a roll-to- roll process, the implementations described may also be performed on discrete substrates.

[0059] Implementations and all of the functional operations described in this specification can be implemented in digital electronic circuitry, or in computer software, firmware, or hardware, including the structural means disclosed in this specification and structural equivalents thereof, or in combinations of them. Implementations described herein can be implemented as one or more non-transitory computer program products, i.e., one or more computer programs tangibly embodied in a machine readable storage device, for execution by, or to control the operation of, data processing apparatus, e.g., a programmable processor, a computer, or multiple processors or computers.

[0060] The processes and logic flows described in this specification can be performed by one or more programmable processors executing one or more computer programs to perform functions by operating on input data and generating output. The processes and logic flows can also be performed by, and apparatus can also be implemented as, special purpose logic circuitry, e.g., an FPGA (field programmable gate array) or an ASIC (application specific integrated circuit).

[0061] The term “data processing apparatus” encompasses all apparatus, devices, and machines for processing data, including by way of example a programmable processor, a computer, or multiple processors or computers. The apparatus can include, in addition to hardware, code that creates an execution environment for the computer program in question, e g., code that constitutes processor firmware, a protocol stack, a database management system, an operating system, or a combination of one or more of them. Processors suitable for the execution of a computer program include, by way of example, both general and special purpose microprocessors, and any one or more processors of any kind of digital computer.

[0062] Computer readable media suitable for storing computer program instructions and data include all forms of nonvolatile memory, media and memory' devices, including by way of example semiconductor memory devices, e.g., EPROM, EEPROM, and flash memory devices; magnetic disks, e.g.. internal hard disks or removable disks; magneto optical disks; and CD ROM and DVD-ROM disks. The processor and the memory7can be supplemented by, or incorporated in, special purpose logic circuitry'.

[0063] The term ‘"comprises” and grammatical equivalents thereof are used herein to mean that other components, ingredients, operations, etc. are optionally present. For example, an article “comprising” (or “which comprises”) components A, B, and C can consist of (i.e., contain only) components A, B, and C, or can contain not only components A, B, and C but also one or more other components. In addition, whenever a composition, an element or a group of elements is preceded with the transitional phrase “comprising” or grammatical equivalents thereof, it is understood that it is contemplated that the same composition or group of elements may be preceded with transitional phrases “consisting essentially of,” “consisting of,” “selected from the group of consisting of,” or “is” preceding the recitation of the composition, element, or elements and vice versa.

[0064] Where reference is made herein to a method comprising two or more defined operations, the defined operations can be carried out in any order or simultaneously (except where the context excludes that possibility ), and the method can include one or more other operations which are carried out before any of the defined operations, between two of the defined operations, or after all of the defined operations (except where the context excludes that possibility).

[0065] While the foregoing is directed to implementations of the present disclosure, other and further implementations of the disclosure may be devised without departing from the basic scope thereof, and the scope thereof is determined by the claims that follow.

Claims

What is claimed is:

1. A flexible substrate processing system comprising: a pickup hub, the pickup hub configured to rotate and assist in conveying a flexible substrate through an interior volume of a calendering unit; the calendering unit comprising a first calender roller and a second calender roller, the first calender roller and the second calender roller configured to rotate, apply pressure, and allow the flexible substrate to pass between the first calender roller and the second calender roller; and a first flexible die. the first flexible die configured to attach to the first calender roller.

2. The flexible substrate processing system of claim 1, wherein the first flexible die comprises a plurality of ridges and a plurality of recesses.

3. The flexible substrate processing system of claim 2, wherein the plurality of ridges and the plurality of recesses are patterned on the first flexible die to form a plurality of lanes.

4. The flexible substrate processing system of claim 3, wherein the plurality of lanes are rectangular in shape and include a width of about 5 cm.

5. The flexible substrate processing system of claim 2, wherein the plurality' of ridges and the plurality of recesses are patterned on the first flexible die to form a skip transfer pattern.

6. The flexible substrate processing system of claim 2, wherein the plurality of ridges and the plurality of recesses are patterned on the first flexible die to form a plurality of lanes and a skip transfer pattern.

7. The flexible substrate processing system of claim 1, wherein the first flexible die is magnetically secured to the first calender roller.

8. The flexible substrate processing system of claim 1, further comprising a first roller positioned adjacent to the calendering unit, wherein the first roller is configured to assist in peeling a first flexible carrier away from the flexible substrate after the flexible substrate leaves the calendering unit.

9. The flexible substrate processing system of claim 1, further comprising a second flexible die. the second flexible die configured to attach to the second calender roller.

10. A device comprising: a first calender roller, the first calender roller including an outer surface; a second calender roller, the second calender roller including an outer surface; and a first flexible die, the first flexible die including a plurality of ridges and a plurality of recesses.

11. The device of claim 10, wherein the first flexible die is magnetically secured to the outer surface of the first calender roller.

12. The device of claim 10, wherein the first flexible die comprise plastic or stainless steel.

13. The device of claim 10, wherein the device further comprises a second flexible die, the second flexible die including a plurality of ridges and a plurality of recesses.

14. The device of claim 10, wherein the ridges and the recesses of the first flexible die are patterned to form a plurality of rectangular lanes of ridges and recesses and each rectangular lane of the plurality of rectangular lanes include a different width.

15. The device of claim 10, wherein the ridges and the recesses of the first flexible die are patterned to form a plurality of rectangular lanes of ridges and recesses and each rectangular lane of the plurality of rectangular lanes include a same width.

16. The device of claim 10, wherein the ridges and the recesses of the first flexible die are patterned to form a skip transfer pattern.

17. The device of claim 10, wherein the ridges and the recesses of the first flexible die are patterned to form a plurality of rectangular lanes of ridges and recesses and a skip transfer pattern.

18. A method, comprising:conveying a flexible substrate, a first flexible carrier, and a second flexible carrier towards a calendering unit, the calendenng unit includes two calender rollers; transferring a first alkali metal film from the first flexible carrier and a second alkali metal film from the second flexible carrier to the flexible substrate by pressure applied by the calender rollers, at least one of the calender rollers including a flexible die; and peeling away the first flexible carrier and the second flexible carrier from the flexible substrate.

19. The method of claim 18, wherein the flexible die includes a pattern determined by ridges and recesses disposed on the flexible die.

20. The method of claim 19, wherein the first alkali metal film and the second alkali metal film are transferred from the first flexible carrier and the second flexible carrier is transferred to the flexible substrate according to the pattern disposed on the flexible die.

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