System and method for dry power modification

Abstract

A system for powder modification is provided. The system includes a substrate including a surface to be coated with powder. The substrate moves in a direction from an upstream end to a downstream end. The system includes a powder deposition unit disposed over the surface of the substrate and configured to deposit the powder onto the substrate to form a powder coating on the substrate. The system includes a conditioning unit disposed downstream of the powder deposition unit and configured to condition the powder coating. The system includes a modification unit disposed upstream of the conditioning unit and configured to modify a characteristic of a mound of the powder collected upstream of the conditioning unit.

Description

Attorney Docket No. 137174.00112SYSTEM AND METHOD FOR DRY POWER MODIFICATION CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims priority to and the benefit of U.S. Provisional Patent Application No. 63 / 777,833, filed on March 26, 2025. The entire content of the foregoing provisional application is incorporated herein by reference in its entirety.BACKGROUND

[0002] A variety of batteries are available in the industry for different uses. Lithium-ion (Li-ion) batteries have generally become the predominant type of battery used in portable consumer electronics and electric vehicles. Fabrication of Li-ion batteries involves numerous steps, each of which can affect the quality of the battery itself, as well as the cost involved in manufacturing the battery. A conventional manufacturing process generally includes formation of an electrode slurry having an active material, a conductive additive, and a binder, mixed in an organic solvent, and the electrode slurry is applied to a metal foil material. Once applied to the foil material, the solvent is dried out or evaporated while the active electrode mixture remains attached to the metal foil material surface. In some instances, the solvent may be toxic and can necessitate additional steps for handling / discarding that increase the overall cost of the manufacturing process. The cost of removing the solvent from the coated material on the metal foil therefore involves an additional step that also increases the overall cost of the manufacturing process.

[0003] An alternative manufacturing technique used in the industry is electrostatic deposition (ESD), which is a solvent-free manufacturing process for electrode coating for Li-ion batteries. See, e.g.. B. Ludwig et al., Solvent-Free Manufacturing of Electrodes for Lithium-ion Batteries, Sci. Rep. 6, Article No. 23150, doi: 10.1038 / srep23150 (2016); M. Wang et al., The Influence of Polyvinylidene Fluoride (PVDF) Binder Properties on LiNio.33Coo.33Mno.33O2 (NMC) Electrodes Made by a Dry-Powder-Coating Process, J. Electrochem. Soc., Vol. 166, No. 10, A2151 (2019); H. Abe et al., Electrostatic Spray Deposition for Fabrication of Li-ion Batteries, Transactions of JWRI, Vol. 44, No. 2 (2015); and U.S. Patent No. 10,547,044). Rather than relying on a solvent mixture, the ESD process uses a dry powder of the active electrode mixture which is applied to the metal foil material. By removing the solvent from the mixture and the drying step from the manufacturing process, the overall process is simplified and becomes more economical, resulting in a viable alternative for large-scale manufacturing. In particular, the solvent-1MEl\60318381.vlAttorney Docket No. 137174.00112free electrode coating technology is an attractive alternative to traditional manufacturing since it can significantly reduce energy consumption in the manufacturing process and thus significantly reduces the manufacturing cost of batteries.

[0004] In a conventional continuous dry powder ESD coating system, a web (e.g., a grounded electrically conductive substrate) passes continuously through a coating chamber while the dry powder mixture is fluidized and pneumatically conveyed from a hopper to an electrostatic spray gun. The electrostatic spray gun electrostatically charges the powders using tribo-charging or corona charging and sprays the charged powders onto the web where they are deposited. Uniform coating of the web is important to achieve optimal operational performance of the resulting product. However, achieving high uniformities of mass loading distribution (i.e., powder coating on the web) can be difficult with ESD coating systems or any other dry deposition based coating systems, especially at high throughputs. The lack of uniform coating can be because of, e.g., inconsistencies in the air stream for distribution of the powder over the web, powder dispensing system inconsistencies, insufficient powder charging, combinations thereof, or the like. As such, conventional dry powder coating systems are unable to offer a high degree of controlled uniformity of the powder particles on the web, with uniformities varying at about + / - 5 % to 15% in mass variation. For optimal operation of the resulting product, a more uniform web coating is desired.SUMMARY

[0005] Embodiments of the present disclosure provide an exemplary system for dry powder modification during an electrode manufacturing process. The system ensures uniformity of the mound (i.e., accumulation) of powder particles directly upstream of the conditioning assembly such that a uniform powder layer is achieved downstream of the conditioning assembly without inconsistencies. The system includes a modification or redistribution unit disposed upstream of and adjacent to the conditioning assembly to substantially continuously (or selectively) modify and adjust the powder particle accumulation upstream of the conditioning assembly to achieve uniformity in the mound across the height, depth and width of the mound.

[0006] In some embodiments, the modification unit can modify, redistribute or adjust the, e.g., height, depth, width, density, mass, geometry, combinations thereof, or the like, of the mound. In some embodiments, the density can be modified or adjusted due to2MEl\60318381.vlAttorney Docket No. 137174.00112breaking up of the powder particles with the modification unit. In some embodiments, the density can be modified or adjusted due to shearing of a collection of powder particles and, in the act of shearing, the powder particles can reduce in density (e.g., expand or dilate) to permit the powder particles to flow around one another during shearing. In some embodiments, the geometry can be modified or adjusted due to the redistribution of powder particles, which changes the height, depth and / or width of the mound.

[0007] The system includes a substrate or web configured to move in a direction from an upstream location to a downstream location. The substrate is coated with powder particles by a powder deposition unit and the substrate is fed towards the conditioning assembly. The conditioning assembly can include a contacting roller located downstream of the powder deposition unit. The contacting roller is configured to contact a free surface of the deposited powder particles on the substrate. The modification unit is located adjacent to the contacting roller, and between the powder deposition unit and the contacting roller.

[0008] Upstream of the nip of the contacting roller, the modification unit engages with the powder particle coating on the substrate to modify and / or redistribute the powder particles at the pre -nip accumulation (e.g.,, mound or feed bank) zone to enable a uniform powder particle layer / coating on the substrate downstream of the nip. The modification unit can, e.g., level, fill, remove, or combinations thereof, the powder particles adjacent to the contact roller to achieve the uniformity in the pre-nip accumulation of powder particles. Modification of the powder particles in the pre-nip accumulation and achieving uniformity in the pre -nip accumulation produces a more uniform powder particle coating / layer downstream of the contacting roller.

[0009] In accordance with embodiments of the present disclosure, an exemplary system for powder modification is provided. The system includes a substrate including a surface to be coated with powder, the substrate moving in a direction from an upstream end to a downstream end. The system includes a powder deposition unit disposed over the surface of the substrate and configured to deposit the powder onto the substrate to form a powder coating on the substrate. The system includes a conditioning unit disposed downstream of the powder deposition unit and configured to condition the powder coating. The system includes a modification unit disposed upstream of the conditioning unit and configured to modify a characteristic of a mound of the powder collected upstream of the conditioning unit.3MEl\60318381.vlAttorney Docket No. 137174.00112

[0010] In some embodiments, the powder deposition unit can include at least one of nozzles, rollers, dispensing tubes, mechanical feeders, or electrostatic powder feeders. The powder coating on the substrate can define an initial coating height measured from the substrate. The mound can define an initial mound height measured from the substrate, and the initial mound height is dimensioned greater than the initial coating height.

[0011] In some embodiments, the characteristic of the mound can be the initial mound height, and the modification unit can be configured to redistribute the powder of the mound to reduce the initial mound height to a modified mound height. The modified mound height can be dimensioned greater than the initial coating height and less than the initial mound height. In some embodiments, the characteristic of the mound can be at least one of a height, a depth, or a width of the mound. In such embodiments, the modification unit can be configured to redistribute the powder of the mound to create uniformity in at least the height, the depth, or the width of the mound along an entire width of the substrate.

[0012] The conditioning unit can include a roller disposed above the substrate and defining a nip through which the powder coating passes to be conditioned. The mound of the powder can be disposed immediately upstream of the roller and can be disposed against an upstream face of the roller. In some embodiments, the modification unit can include a powder plow configured to slide along a rail extending across a width of the substrate. The powder plow can include a bottom edge configured to engage with the powder of the mound to modify the characteristic of the mound. In some embodiments, the powder plow can include a front face with a configuration complementary to an upstream face of a roller of the conditioning unit.

[0013] In some embodiments, the modification unit can include multiple powder plows configured to slide along a rail extending across a width of the substrate, each of the multiple powder plows including a bottom edge configured to engage with the powder of the mound to modify the characteristic of the mound. In some embodiments, the modification unit can include a rotary plow assembly including multiple powder plows extending from a rotating circuit such that each of the multiple powder plows intermittently engage with the powder of the mound to modify the characteristic of the mound.

[0014] In some embodiments, the modification unit can include a rotating auger including an auger blade rotating along a central axis extending across a width of the substrate. The auger blade engages with the powder of the mound to modify the4MEl\60318381.vlAttorney Docket No. 137174.00112characteristic of the mound. In some embodiments, the modification unit can include a sonotrode disposed over the substrate and configured to generate vibrations to redistribute the powder of the mound to modify the characteristic of the mound. In some embodiments, the modification unit can include an air manifold including orifices configured to be selectively opened or closed to expel air onto the mound to redistribute the powder of the mound to modify the characteristic of the mound. In some embodiments, the modification unit can include an electrode charging unit configured to selectively charge the powder of the mound to redistribute the powder of the mound to modify the characteristic of the mound. In some embodiments, the modification unit can include one or more fins configured to confine lateral spreading of the powder of the mound.

[0015] In accordance with embodiments of the present disclosure, an exemplary system for powder modification is provided. The system includes a substrate including a surface to be coated with powder, the substrate moving in a direction from an upstream end to a downstream end. The system includes a powder deposition unit disposed over the surface of the substrate and configured to deposit the powder onto the substrate to form a powder coating on the substrate. The system includes a conditioning unit disposed downstream of the powder deposition unit and configured to condition the powder coating. The conditioning unit includes a roller disposed over the substrate and define a nip through which the powder coating is passed for conditioning. The system includes a modification unit disposed upstream of the conditioning unit and configured to redistribute the powder of a mound of the powder collected upstream of the roller of the conditioning unit to modify a characteristic of the mound.

[0016] In accordance with embodiments of the present disclosure, an exemplary method of powder modification is provided. The method includes moving a substrate from an upstream end to a downstream end, the substrate including a surface to be coated with powder. The method includes depositing the powder onto the substrate with a powder deposition unit disposed over the surface of the substrate to form a powder coating on the substrate. The method includes conditioning the powder coating with a conditioning unit dispose downstream of the powder deposition unit. The method includes modifying a characteristic of a mound of the powder collected upstream of the conditioning unit with a modification unit disposed upstream of the conditioning unit.

[0017] Any combination and / or pennutation of embodiments is envisioned. Other objects and features will become apparent from the following detailed description 5MEl\60318381.vlAttorney Docket No. 137174.00112considered in conjunction with the accompanying drawings. It is to be understood, however, that the drawings are designed as an illustration only and not as a definition of the limits of the present disclosure.BRIEF DESCRIPTION OF THE DRAWINGS

[0018] To assist those of skill in the art in making and using the system for dry powder modification, reference is made to the accompanying figures, wherein:

[0019] FIG. 1 is a diagrammatic view of an exemplary spreader roller coating system.

[0020] FIG. 2 is a diagrammatic view of spreading rollers of an exemplary spreader roller coating system, including a mound formation upstream of an upper spreading roller.

[0021] FIG. 3 is a diagrammatic view of spreading rollers of an exemplary spreader roller coating system, including a powder particle coating height variation upstream of the spreading rollers.

[0022] FIG. 4 is a chart illustrating a powder particle coating thickness relative to a substrate of an exemplary spreader roller coating system, prior to and after passing through a nip of spreading rollers.

[0023] FIG. 5 is a diagrammatic view of spreading rollers of an exemplary spreader roller coating system, including a mound formation zone upstream of an upper spreading roller.

[0024] FIG. 6 is a diagrammatic, top view of a spreading roller of an exemplary spreader roller coating system, including an inconsistent mound formation upstream of the spreading roller and inconsistencies in a powder particle coating downstream of the spreading roller.

[0025] FIG. 7 is a diagrammatic view of an exemplary system for dry powder modification in accordance with embodiments of the present disclosure, including a modification unit upstream of a conditioning unit.

[0026] FIG. 8 is a diagrammatic, detailed view of an exemplary system for dry powder modification in accordance with embodiments of the present disclosure, including a conditioning roller and powder coating thicknesses upstream and downstream of the conditioning roller.6MEl\60318381.vlAttorney Docket No. 137174.00112

[0027] FIG. 9 is a diagrammatic, detailed view of an exemplary system for dry powder modification in accordance with embodiments of the present disclosure, including a conditioning roller and a mound formed upstream of the conditioning roller.

[0028] FIG. 10 is a diagrammatic, top view of an exemplary system for dry powder modification in accordance with embodiments of the present disclosure, including a modification unit in the form of a powder plow.

[0029] FIG. 11 is a diagrammatic, detailed side view of an exemplary system for dry powder modification in accordance with embodiments of the present disclosure, including a modification unit in the form of a powder plow.

[0030] FIG. 12 is a perspective view of an exemplary system for dry powder modification in accordance with embodiments of the present disclosure, including a modification unit in the form of a powder plow.

[0031] FIG. 13 is a perspective view of a modification unit of an exemplary system for dry powder modification in accordance with embodiments of the present disclosure, in the form of a powder plow.

[0032] FIG. 14 is a side view of a modification unit of FIG. 13.

[0033] FIG. 15 is a rear view of a modification unit of FIG. 13.

[0034] FIG. 16 is a perspective view of a plow of a modification unit of an exemplary system for dry powder modification in accordance with embodiments of the present disclosure.

[0035] FIG. 17 is side rear view of a plow of FIG. 16.

[0036] FIG. 18 is a perspective view of a plow of a modification unit of an exemplary system for dry powder modification in accordance with embodiments of the present disclosure.

[0037] FIG. 19 is a side view of a plow of FIG. 18.

[0038] FIG. 20 is a perspective view of a plow of a modification unit of an exemplary system for dry powder modification in accordance with embodiments of the present disclosure.

[0039] FIG. 21 is a side view of a plow of FIG. 20.7MEl\60318381.vlAttorney Docket No. 137174.00112

[0040] FIG. 22 is a diagrammatic, top view of an exemplary system for dry powder modification in accordance with embodiments of the present disclosure, including a modification unit in the form of multiple powder plows.

[0041] FIG. 23 is a diagrammatic, rear view of an exemplary system for dry powder modification in accordance with embodiments of the present disclosure, including a modification unit in the form of a rotary plows.

[0042] FIG. 24 is a diagrammatic, top view of an exemplary system for dry powder modification in accordance with embodiments of the present disclosure, including a modification unit in the form of a rotating auger.

[0043] FIG. 25 is a diagrammatic, top view of an exemplary system for dry powder modification in accordance with embodiments of the present disclosure, including a modification unit in the form of a sonotrode (vibration hom).

[0044] FIG. 26 is a diagrammatic, top view of an exemplary system for dry powder modification in accordance with embodiments of the present disclosure, including a modification unit in the form of an air manifold.

[0045] FIG. 27 is a diagrammatic, top view of an exemplary system for dry powder modification in accordance with embodiments of the present disclosure, including a modification unit in the form of an electrode charging unit.

[0046] FIG. 28 is a diagrammatic, top view of an exemplary system for dry powder modification in accordance with embodiments of the present disclosure, including a modification unit in the form of a selective powder dispersion assembly.

[0047] FIG. 29 is a diagrammatic, top view of an exemplary system for dry powder modification in accordance with embodiments of the present disclosure, including a modification unit in the form of a selective powder removal assembly.

[0048] FIG. 30 is a diagrammatic, top view of an exemplary system for dry powder coating with lateral spreading of a powder mound up to lateral edges of a substrate.

[0049] FIG. 31 is a diagrammatic, top view of an exemplary system for dry powder modification in accordance with embodiments of the present disclosure, including lateral fins or guides configured to minimize or prevent lateral spreading of a powder mound beyond a set edge location.8MEl\60318381.vlAttorney Docket No. 137174.00112

[0050] FIG. 32 is a diagrammatic, perspective view of an exemplary system for dry powder modification in accordance with embodiments of the present disclosure, including lateral fins or guides configured to minimize or prevent lateral spreading of a powder mound beyond a set edge location.

[0051] FIG. 33 is a diagrammatic, side view of an exemplary system for dry powder modification of FIG. 32.

[0052] FIG. 34 is a perspective view of an exemplary system for dry powder modification in accordance with embodiments of the present disclosure, including lateral fins or guides configured to minimize or prevent lateral spreading of a powder mound beyond a set edge location.DETAILED DESCRIPTION

[0053] FIG. 1 illustrates an exemplary manufacturing process for coating of a web referred to as “spreader roller coating”. The exemplary spreader roller coating system 10 generally includes a reservoir or chamber 12 that receives and dispenses powder particles 14 onto a moving substrate 16 (e.g., a current collector foil). Rollers 18, 20 on opposite ends of the system 10 maintain movement of the substrate 16 along a substrate direction 22. The substrate 16 is passed through a pair of spreading rollers 24, 26 to spread and distribute the powder particles 14 on the surface of the substrate 16 to achieve a coating on the substrate 16 having a first thickness 28. The substrate 16 is subsequently passed through a pair of calender rollers 30, 32 which compress and densify the powder particles 14 to a second thickness 34. The calender rollers 30, 32 densify and compress the powder particles onto the substrate surface, with such compression and densification causing the powder particles to adhere to each other and the substrate 16. Compression and densification performed by the calender rollers 30, 32 with or without heating promote cohesion and adhesion of the powder particles 14 to the substrate 16, and after such process, a dry electrode is produced. Elements of spreader roller coating technology is described in, e.g.. International Patent Application No. PCT / US23 / 69175, which are incorporated herein by reference in its entirety.

[0054] The powder particles 14 dispensed onto the substrate 16 pass through a nip 36 between the rollers 24, 26. A nip 36, as the term is used herein, refers to a thin gap at points of closest approach between the outer diameters of the rollers 24, 26. Due to the smaller size of the nip 36 relative to the initial height of powder particles 16 dispensed onto the 9MEl\60318381.vlAttorney Docket No. 137174.00112substrate 16, the roller 24 levels, distributes, spreads and / or compacts the powder particles 16 to achieve the coating on the substrate 16 having the first thickness 28. However, as the powder particles 16 pass through the nip 36, the remaining powder particles 16 can accumulate immediately upstream of the roller 24 to form a mound 38 of powder particles 16. As used herein, the term mound 38 refers to an accumulation of powder particles 16 immediately upstream of and in contact with the upstream face of the roller 24.

[0055] The mound 38 can define a height as measured from the top surface of the substrate 16, a depth as measured from the roller 24 along the direction 22, and a width as measured across the width of the substrate 16 (perpendicular to the direction 22). Due to non-uniformities in the powder particles 16 dispensed onto the substrate 14, in addition to general build-up of powder particles 16 forming the mound 38, inconsistencies in the height, depth and width of the mound 38 can occur along the roller 24. Such inconsistencies can result in non-uniformities (e.g., streaks, or the like) of the powder particle 16 coating downstream of the roller 24.

[0056] FIG. 2 is a side view of the system 10 including the spreading rollers 24, 26, and a mound 38 formed upstream of the roller 24 (and upstream of the nip 36). As powder particles 14 are dispensed onto the substrate 16, the powder particles 14 form an initial coating having a thickness 40 (as measured from the top surface of the substrate 16). FIG. 3 is a side view of the system 10 of FIG. 2, illustrating inconsistencies and / or variations in the powder particles 14 coating approaching the roller 24. In practice, the initial coating of the powder particles 14 along the substrate 16 surface varies based on, e.g., inconsistencies in dispersion of the powder particles 14, environmental conditions, substrate conditions, combinations thereof, or the like. Thus, although the system 10 may operate optimally at a preferred height 42 of the initial coating, in reality, due to the inconsistencies of the powder particles 14 upstream of the roller 24, inconsistencies in the coating height 40 exist. These inconsistencies can affect not only the size of the mound 38 forming upstream of the roller 24, but also the uniformity of the mound 38 height, depth and / or width along the roller 24.

[0057] FIG. 4 is a chart illustrating the inconsistency and / or variation in the powder particle 14 coating thickness 40, with “x” defining the web direction and “t” defining the thickness 40 of the powder particle 14 coating. Along direction “x”, position 0 represents the nip 36 between the rollers 24, 26. Thus, before the nip 36, the powder particle thickness 40 varies based on deposition of the powder particles 14 on the substrate 16. As the powder 10MEl\60318381.vlAttorney Docket No. 137174.00112particles 14 approach the roller 24 (and the nip 36), the mound 38 is formed and the thickness of the mound 38 increases relative to the thickness 40 upstream of the mound 38. As the powder particles 14 are passed towards the nip 36, the thickness gradually reduces in a zone 44 until the powder particles 14 are spread (and potentially compressed) to a downstream thickness 46. FIG. 4 shows the optimal (i.e., uniform) thickness 46 of the powder particle coating downstream of the roller 24. However, in reality, due to the mound 38 formation and inconsistencies in the height, depth and / or width of the mound 38, inconsistencies in the downstream thickness 46 occur.

[0058] FIG. 5 is a diagrammatic side view of the system 10 including a mound formation zone 48 upstream of the roller 24. The zone 48 can generally define a height 50, a depth 52, and a width (perpendicular to the direction 22) in which the mound 38 can form. Based on inconsistencies in the powder particle 14 initial coating thickness 40 approaching the roller 24, inconsistencies in one or more of the height 50, depth 52, and / or width of the mound 38 can occur.

[0059] FIG. 6 is a diagrammatic top view of the system 10, including a mound 38 formed upstream of the roller 24. As discussed, various inconsistences and / or variations (e.g., streaks 54, clumps 56, voids, general non-uniformities in the loading distribution, combinations thereof, or the like) in the powder particle 14 coating can occur upstream of the roller 24. The various inconsistences and / or variations can result in a non-uniform edge 58 of the mound 38 formation upstream of the roller 24, as well as non-uniformities in the mound 38 height and / or width. For example, the central area of the roller 24 can form the widest, deepest and highest mound 38, while the lateral / side areas of the roller 24 can be smaller. Clumps or clusters 60 of powder particles 14 can also be trapped in the mound 38. Although the roller 24 receives a portion of the powder particles 14 through the nip 36 and a coating 62 is generated downstream of the roller 24, due to the inconsistencies in the mound 38, the coating 62 can include variations and / or inconsistencies 64. These inconsistencies 64 can include, e.g., streaks in the coating 62 with low and / or high points, localized powder accumulations leading to high points, voids in the coating, out of specification mass loading distributions which are more random in nature, or the like. In some instances, the inconsistencies in the mound 38 can lead to critical failure of the powder particle coating 62 or the substrate 16, leading to lost time and / or material. As a result, the electrode formed from the substrate 16 includes inconsistencies that can affect the operational quality of the electrode. The exemplary modification unit discussed herein11MEl\60318381.vlAttorney Docket No. 137174.00112can be used in combination with the system 10 to minimize or completely prevent these inconsistencies.

[0060] The term “mound” as used herein refers to any amount of powder accumulation greater in height and / or depth over a threshold / baseline height and / or depth of powder. For example, the system is intended to apply a predetermined thickness of powder onto the web and the conditioning unit is designed to redistribute the powder to a desired, substantially uniform thickness prior to compression. The predetermined thickness of powder defines the threshold / baseline thickness of powder. Any amount of powder with a height above this predetermined thickness is considered a “mound”, which can include a height (as measured from the web surface or the predetermined powder thickness surface), a width (as measured along the width of the web perpendicular to the web moving direction), a depth (as measured along the web moving direction). According to some embodiments, the mound can include, or be additionally characterized by a geometry / profile observed at cross-sections of the mound from a side view (along the depth and height) and from a top view (along the width and depth).

[0061] In some embodiments, any amount of powder build up above the predetermined thickness and / or depth can define an unacceptable mound detectable by the system. In some embodiments, any amount of powder below the predetermined thickness and / or depth can necessitate adjustment of the system to reach the predetermined thickness and / or depth at the roller (e.g., by depositing more powder onto the web to reach the desired predetermined thickness and / or depth of powder). In some embodiments, any inconsistencies or gaps in the width of the mound can necessitate adjustment of the system to reach a uniformity and consistency in the width of the powder across the width of the web. In some embodiments, the system can operate with an acceptable or desired mound, i.e., a mound having acceptable / desired height (a height above the threshold / baseline thickness of powder), width and / or depth characteristics that do not necessitate adjustment by the system. In such embodiments, the acceptable mound characteristics can be used as the threshold / baseline to which the modification unit is operated to modify the pre-nip accumulation. For example, the modification unit can be operated substantially continuously to avoid increase (or decrease) of the pre-nip accumulation above the acceptable or baseline characteristics of the mound.

[0062] In some embodiments, the powder particles can be a composite including active materials and binder materials. In some embodiments, electric conductive materials12MEl\60318381.vlAttorney Docket No. 137174.00112can be added into the composite powder particle mixture. In some embodiments, the weight ratio of active material (relative to the remainder of other components / materials) in the powder particles can be about, e.g., 1-100% inclusive, 70-90% inclusive, 80-90% inclusive, 90-100% inclusive, or the like. In some embodiments, the weight ratio of active materials can be at least, e.g., 70%, 80%, 90%, or the like, with the remainder including other components / materials. In some embodiments, the other components / materials can be powder materials other than active powder materials in the mixture. In some embodiments, the other components / materials can include, e.g., binder materials (such as polymer binder materials, for example), conductive materials (such as conductive carbonbased or carbon-containing materials, for example), combinations thereof, or the like. In some embodiments, the weight ratio of active material (relative to the remainder of other components / materials) in the powder particles can be, e.g., more than 70%, or the like.

[0063] In some embodiments, the powder particles can include composite particles, where a first set of particles is attached , adhered, bound, or otherwise stuck onto a second set of particles. In such embodiments, each of the first set of particles is dimensioned smaller than each of the second set of particles. In some embodiments, the smaller particle size can be less than about 1 um, and the bigger particle size can be larger than about 1 um. In some embodiments, the first and second sets of particles can be characterized by an average particle size using, e.g., a volume-based average, or the like. In some embodiments, the first and second sets of particles can exhibit average particle sizes different by between a factor of, e.g., 10 and 100 inclusive, 50 and 200 inclusive, 100 and 500 inclusive, 200 and 2,000 inclusive, greater than a factor of 2,000, or the like. By way of a non-limiting example, an average diameter of the smaller of the two sets of particles can be about 1 nanometer and the larger o the two sets of particles can be about 5 micrometers, for a factor of 5,000. In some embodiments, the bigger particles can be active materials, e.g., cathode materials for a battery, anode materials for a battery, combinations thereof, or the like. In some embodiments, the smaller particles can be, e.g., polymer binder materials, a mixture of binder and conductive materials, combinations thereof, or the like. In some embodiments, the weight ratio of active material (relative to binder, conductive materials and / or other non-active materials) in the powder can be about, e.g., 1-100% inclusive, or the like. In some embodiments, the weight ratio of active material (relative to binder, conductive materials and / or other non-active materials) in the powder can be, e.g., more than 70%, or the like. In some embodiments, the weight ratio of active material13MEl\60318381.vlAttorney Docket No. 137174.00112(relative to binder, conductive materials and / or other non-active materials) in the powder can be about, e.g., 50-100% inclusive, 60-100% inclusive, 70-100% inclusive, 80-100% inclusive, 90-100% inclusive, 95-100% inclusive, 96-97% inclusive, or the like. In some embodiments, higher percentages (by weight) of the active materials can be used, since the volumetric and gravimetric energy density of the battery (among other performance metrics) are improved when greater amounts of active material are included.

[0064] In some embodiments, the active materials in a rechargeable battery or a lithium ion battery can include cathode materials (such as, e.g., lithium metal oxide), cathode materials (such as, e.g., NCM (Lithium Nickel Cobalt Manganese Oxide), LMO (Lithium Manganese Oxide), NCA (Lithium Nickel Cobalt Aluminum Oxide), LCO (Lithium Cobalt Oxide), lithium polyanion type cathode materials (such as, e.g., LFP (Lithium Iron Phosphate), LiMnxFei-xPO4, Li2FeSiO4), and / or anode materials (e.g., based on carbonaceous anode materials, graphite, Si, Si-based composites, SiOx, lithium alloyable materials, or lithium transition metal oxide anode materials). In a sodium-ion battery, the active materials can include cathode materials (including, e.g., sodium transition metal oxide, such as Na2 / sFei / 2Mni / 2O2, sodium polyanion materials, such as Na2MnSiO4, Prussian Blue Analogues), cathode materials (such as, e.g., Na2MnFe(CN)e), and / or anode materials (including, e.g., carbonaceous anode, sodium alloyable materials, sodium transition metal oxide, or Prussian Blue Analogues anode materials).

[0065] In some embodiments, the active materials in the powder particle mixture can include, e.g., solid electrolyte materials, including LidnCL and LLZO materials, or the like.

[0066] In some embodiments, the binder materials can include polymeric materials (such as, e.g., PVDF (polyvinylidene fluoride), PTFE (Polytetrafluoroethylene), PEO (Polyethylene oxide), or PMMA (Poly(methyl methacrylate)), SBR (Polystyrene butadiene rubber binder), CMC (Carboxymethyl cellulose binder), or PAA (Polyacrylic acid), or polyolefins, which are electrical insulators), or the like. In some embodiments, the binder materials can be polymer electrolytes (such as, e.g., PEO / lithium triflate polymer electrolyte, or the like). In some embodiments, the binder can be solid state electrolyte composites (including, e.g., inorganic solid electrolytes and polymeric binders, polymer electrolyte binders or organic binders, such as LhlnCk / PMMA composite, LLZO / polymer electrolyte composite, or the like).

[0067] In some embodiments, the conductive materials can include, e.g., carbon black14MEl\60318381.vlAttorney Docket No. 137174.00112(CB), carbon nanotubes, graphene, conductive polymer materials, or inorganic conductive materials, which are electrically conductive. In some embodiments, functional additives can be included in the composite electrode. In such embodiments, the functional additives can be, e.g., silica, alumina, zirconium oxide, combinations thereof, or the like.

[0068] In some embodiments, the acceptable height threshold for the powder mound can be based on the engagement of the powder mound with the roller surface and the measured angle (e.g., the wetted angle). In some embodiments, the acceptable depth of the powder mound (as measured from the roller surface) can be between about, e.g., 0.5 mm-50 mm inclusive, 0.5 mm-40 mm inclusive, 0.5 mm-30 mm inclusive, 0.5 mm-20 mm inclusive, 0.5 mm-10 mm inclusive, 10-50 mm inclusive, 20-50 mm inclusive, 30-50 mm inclusive, 40-50 mm inclusive, 10-40 mm inclusive, 20-30 mm inclusive, 0.5 mm, 5 mm, 10 mm, 20 mm, 30 mm, 40 mm, 50 mm, or the like. In some embodiments, the acceptable width of the powder mound can be dependent on the width of the substrate / web and the coated area of the web. For example, the mound width can be at least as wide as the coating width and should not be more than about 25 mm wider than the coating area. As an example, the substrate can be about 280 mm with a coating width of about 250 mm. In such example, the mound width can be at least 250 mm wide, but should not exceed 275 mm, thereby maintaining a gap with the side edge of the substrate.

[0069] In some embodiments, the system can include a monitoring / feedback loop that allows for detecting characteristics of the mound, and automatically adjusts operation of the modification unit to adjust or modify the mound for optimized conditioning and compression. In some embodiments, the modification unit can be controlled and set to maintain a predetermined height of the mound. However, if one or more sensors detect that inconsistencies or variations of the powder particles exists below the predetermined height, depth and / or width (e.g., gaps of powder along the width), the monitoring / feedback loop can transmit signals to a controller to regulate operation of the modification unit to selectively add powder particles (and / or the powder deposition unit) to achieve the desired characteristics of the mound. In some embodiments, the system can include means for monitoring of powder as it enters the powder conditioning unit, sensing one or more of the characteristics of the powder mound, and using the powder mound characteristics to control the modification unit (and / or the powder deposition unit). In some embodiments, system parameters can include, but are not limited to, parameters such as, e.g., components of the powder deposition unit, the web speed, components of the powder conditioning unit that15MEl\60318381.vlAttorney Docket No. 137174.00112may be adjusted to deliver more powder in some cases or less powder in other cases, combinations thereof, or the like. Significantly improved uniformity in the mound can therefore be achieved in the pre-nip accumulation, resulting in improved uniformity in the powder particle coating downstream of the conditioning unit and further resulting in a higher quality electrode.

[0070] FIG. 7 is a diagrammatic view of an exemplary system for dry powder modification (hereinafter “system 100”). The system 100 can be used to manufacture a coated substrate usable in, e.g., Li-ion batteries, solid state batteries, or the like. The system 100 can be incorporated into an containment enclosure (e.g., a containment chamber) for deposition of the powder particle coating onto a substrate or web 102, e.g., a continuously moving substrate or web 102. The web 102 includes a top surface 104 on which the powder coating is applied. The powder coating includes at least a cathode material or an anode material, e.g., for rechargeable lithium batteries, or the like. In some embodiments, the bottom surface 106 of the web 102 can also receive the powder coating either concurrently with the top surface 104 or subsequent to the top surface 104 being coated. Rollers 108, 110 are positioned on opposite proximal and distal ends (e.g., upstream and downstream ends) of the web 102 and suspend the web 102 as it passes through the containment enclosure. The rollers 108, 110 rotate in a combined manner to maintain the continuous movement of the web 102 through the containment enclosure in a web direction 112. Although two rollers 108, 110 are illustrated, it should be understood that the system 100 can include a single roller, or multiple rollers.

[0071] The system 100 includes a dry powder deposition unit 114 positioned over the web 102. Although FIG. 7 shows a single deposition unit 114, it should be understood that the system 100 can include one or more deposition units 114 positioned along the web 102. The deposition unit 114 deposits dry powder particles on the web 102 to produce a powder coating on the web 102 with a high uniformity (i.e., a higher uniformity as compared to ESD systems). In some embodiments, the deposition unit 114 can be any one or combination of the following ESD systems using powder dispersion systems, e.g., nozzles, rollers, dispensing tubes, mechanical feeders, electrostatic powder feeders, vibration feeders, electrostatic spray deposition, combinations thereof, or the like, and in the case of electrostatic powder deposition any one or combination of the following charging mechanisms, e.g., corona discharge (positive or negative), tribo-charging, direct conduction charging, induction charging, dielectric barrier discharges, other non-thermal16MEl\60318381.vlAttorney Docket No. 137174.00112plasmas, or the like. In some embodiments, the deposition unit 114 can include one or more features of those disclosed in International Patent Application No. PCT / US23 / 26276, filed on June 27, 2023; International Patent Application No. PCT / US23 / 82635, filed on December 6, 2023; and International Patent Application No. PCT / US24 / 18424, filed on March 4, 2024, each of which is incorporated herein by reference.

[0072] In some embodiments, one or more of the operating parameters can be selected as described herein. Nozzle -based dispersion systems can be in the form of an array of nozzles with individual powder feeding mechanisms or distributed orifices on a distribution channel (e.g., tube, bar, or the like) with a single powder feeding manifold. For nozzlebased dispersion systems, powders can be dispensed into a pneumatic conveying line via a venturi type pick-up adaptor or directly from a fluidizing hopper. The powders can be dispensed continuously into the conveying line using twin mechanical feeders, such as twin-screw augers, vibratory tables, rotary brush feeders, hoppers with valves, conveying belts, or the like, which are gravimetrically or volumetrically controlled to assure a repeatable and accurate mass flow rate of powder. The powders can be conveyed using compressed air in the range of about 20-140 psi which is dry of moisture and free of contaminates. The volumetric flow rate of the conveying air and the mass flow rate of the powder can be balanced to assure the powder stays in suspension during conveying and does not build up in the conveying lines. This is a function of the desired coated layer mass loading. A liner material of suitable selection based on the tribo-electrification series compared to the coating powder can be added to the conveying lines to tribo-charge the powders during conveying.

[0073] Roller-based dispensing and dispersion systems can be utilized by placing a hopper over the roller and continuously rotating the roller. The roller can include indents or voids on the surface to allow powder to fall in and be conveyed during rotation to a coating chamber. A perpendicularly oscillating brush or second roller can be used to remove the powder from the dispensing roller surface indents. In some embodiments, a cylindrical brush can rotate about an axis substantially parallel to the rotating roller on which powder is lodged, and the brush can be arranged to interfere with at least the powder and / or surface features upon which the powder is arranged to dispense the powder from the roller. This assembly forms a powder scattering system. Typically, the dispensing roller does not rotate faster than a 1 m / s tip velocity. In some embodiments, this roller-based dispensing system can be coupled with air to further disperse the powder to be effectively17MEl\60318381.vlAttorney Docket No. 137174.00112charged and coated (e.g., as is described in International Patent Application No. PCT / US24 / 18424, filed on March 4, 2024, which is incorporated herein by reference in its entirety).

[0074] In some embodiments, deploying acoustics to the powder in-flight can assist with dispersing the powders more uniformly before depositing. In some embodiments, frequencies in the range of about 50-1000 Hz with intensities greater than about 30 dB can be applied to achieve a dispersion response, with the values selected based on the powder particle size and / or morphology. In some embodiments, exposure to acoustic waves can assist with breaking up agglomerates that may have formed in an upstream process. It should be understood that this method of breaking up agglomerates does not require physical, mechanical, solid-to-solid, or otherwise direct contact with the powder being dispensed and may constitute or result in a non-contact dispensing mechanism.

[0075] Powder charging using corona discharges can be achieved by applying a high voltage with a magnitude in the range of about 2-100 kV to produce a non-arcing discharge at moderate currents, typically below about 5 mA, to a discharge electrode with discharge radiuses less than about 2 mm. A negative corona or positive corona can be utilized by setting the polarity of the potential applied to the discharge electrodes. In some embodiments, negative coronas can be used due to a lower corona onset electric field strength. In some embodiments, a positive corona can be used based on the powder particle chemical composition and morphology. The corona discharge electrodes can be deployed in a strategic manner to optimize particle charging and particle transport in the applied electric field. These charging electrodes can take a variety of forms, such as points, wires, meshes, plates, or any combination thereof. Some configurations are described in International Patent Application No. PCT / US23 / 26276, filed on June 27, 2023, and International Patent Application No. PCT / US24 / 18424, filed on March 4, 2024, both of which are incorporated herein by reference in their entirety.

[0076] Direct conduction charging can be utilized by applying a high voltage to a conductive surface in the range of about 2-100 kV with currents typically below about 5 mA for a single electrode. A high degree of surface contact between the powder particles and the charging surface is typically required to achieve efficient charging.

[0077] Controlling environmental conditions, such as humidity, temperature, pressure, atmospheric gas composition, contaminants, combinations thereof, or the like,18MEl\60318381.vlAttorney Docket No. 137174.00112can assist with maintaining process control and stability. In some embodiments, the humidity can be maintained to about +1-2% relative humidity at room temperature or better from the target. In some embodiments, a partial pressure of water vapor can be maintained to about +1-2% of a target value of a partial pressure of water vapor. In some embodiments, the temperature can be maintained within about + / -1.5°C or better from the target. In some embodiments, the environment pressure can be maintained to within about + / -0.05 inches of water column from target or better. In some embodiments, atmospheric gas composition can be maintained within about + / -1.5 wt% or target. In some embodiments, contaminates can be maintained to less than about 1000 ppm or better, and can be largely dependent on the final product requirement(s) and less about the process stability.

[0078] In some embodiments, a dry room manufacturing environment can be used for the exemplary system 100. The dry room manufacturing environment can be configured to maintain low amounts of water vapor, typically specified with a dew point in degrees Centigrade. In some embodiments, the environment can be controlled to a dew point of between about, 1 to -15 °C inclusive, 10 to -30 °C inclusive, -25 to -45 °C inclusive, -40 to -65 °C inclusive, lower than -60 °C, or the like.

[0079] In some embodiments, the system 100 can optionally include a powder removal unit 116 disposed downstream of the powder deposition unit 114. The removal unit 116 can include, e.g., a vacuum, blades, wipers, or the like, configured to selectively remove powder particles from the web 102. For example, the removal unit 116 can be operated to selectively remove powder particles from edges of the web 102, thereby forming lanes on the opposing edges of the web 102. In some embodiments, lanes can be formed between the side edges of the web 102 as well. The removal unit 116 is disposed upstream of a conditioning unit 118. In some embodiments, the removal unit 116 can similarly be positioned downstream of the conditioning unit 118. In some embodiments, the system 100 can include multiple removal units 116 disposed upstream and / or downstream of the conditioning unit 118.

[0080] The conditioning unit 118 can include one or more components that engage with the powder particles dispensed onto the web 102, with such engagement spreading, smoothening, and / or compacting, the powder particles along the web 102. As shown in FIG. 7, the conditioning unit 118 can include one or more pairs of rollers 120, 122 disposed above and below the web 102, respectively. The conditioning unit 118 is therefore used to alter the powder particles distribution on the web 102 and is intended to ensure the 19MEl\60318381.vlAttorney Docket No. 137174.00112uniformity of the powder particle coating layer on the web 102.

[0081] After passing through the conditioning unit 118, the system 100 can optionally include a heating unit 124 through which the web 102 can pass. The heating unit 124 can assist with bonding of the powder particles to each other and the web 102 prior to entry through a calendering unit 126. In some embodiments, the system 100 can optionally include a secondary conditioning unit 128 with rollers 130, 132 disposed downstream of the conditioning unit 118 and upstream of the calendering unit 126, to further condition the powder particle coating prior to calendering.

[0082] The calendering unit 126 can include one or more pairs of rollers 134, 136 that perform compaction of the powder particles onto the surface of the web 102, and relative to each other. Although only a single pair of rollers 134, 1 6 is shown in FIG. 7, it should be understood that one or more pairs of calendering rollers 134, 136 could be used for compaction of the powder particle coating. In some embodiments, heat can be applied before, during and / or after the compaction steps.

[0083] In some embodiments, the compressive force applied by the calendering unit 126 to form the coating layer can be about, e.g., 10-4000 N / mm inclusive, 10-3900 N / mm inclusive, 10-3800 N / mm inclusive, 10-3700 N / mm inclusive, 10-3600 N / mm inclusive, 10-3500 N / mm inclusive, 10-3400 N / mm inclusive, 10-3300 N / mm inclusive, 10-3200 N / mm inclusive, 10-3100 N / mm inclusive, 10-3000 N / mm inclusive, 10-2900 N / mm inclusive, 10-2800 N / mm inclusive, 10-2700 N / mm inclusive, 10-2600 N / mm inclusive, 10-2500 N / mm inclusive, 10-2400 N / mm inclusive, 10-2300 N / mm inclusive, 10-2200 N / mm inclusive, 10-2100 N / mm inclusive, 10-2000 N / mm inclusive, 10-1900 N / mm inclusive, 10-1800 N / mm inclusive, 10-1700 N / mm inclusive, 10-1600 N / mm inclusive, 10-1500 N / mm inclusive, 10-1400 N / mm inclusive, 10-1300 N / mm inclusive, 10-1200 N / mm inclusive, 10-1100 N / mm inclusive, 10-1000 N / mm inclusive, 10-900 N / mm inclusive, 10-800 N / mm inclusive, 10-700 N / mm inclusive, 10-600 N / mm inclusive, 10-500 N / mm inclusive, 10-400 N / mm inclusive, 10-300 N / mm inclusive, 10-200 N / mm inclusive, 10-100 N / mm inclusive, 10-50 N / mm inclusive, 10-20 N / mm inclusive, 20-4000 N / mm inclusive. 30-4000 N / mm inclusive, 40-4000 N / mm inclusive, 50-4000 N / mm inclusive, 100-4000 N / mm inclusive, 200-4000 N / mm inclusive, 300-4000 N / mm inclusive, 400-4000 N / mm inclusive, 500-4000 N / mm inclusive, 600-4000 N / mm inclusive, 700-4000 N / mm inclusive, 800-4000 N / mm inclusive, 900-4000 N / mm inclusive, 1000-4000 N / mm inclusive, 1100-4000 N / mm inclusive, 1200-4000 N / mm 20MEl\60318381.vlAttorney Docket No. 137174.00112inclusive. 1300-4000 N / mm inclusive, 1400-4000 N / mm inclusive, 1500-4000 N / mminclusive, 20-1500 N / mm inclusive, 20-1000 N / mm inclusive, 20-500 N / mm inclusive, 20- 300 N / mm inclusive, 1000-3000 N / mm inclusive, 1500-2500 N / mm inclusive, 10 N / mm, 20 N / mm, 30 N / mm, 40 N / mm, 50 N / mm, 60 N / mm, 70 N / mm, 80 N / mm, 90 N / mm, 100 N / mm, 200 N / mm, 300 N / mm, 400 N / mm, 500 N / mm, 600 N / mm, 700 N / mm, 800 N / mm, 900 N / mm, 1000 N / mm, 1100 N / mm, 1200 N / mm, 1300 N / mm, 1400 N / mm, 1500 N / mm, 1600 N / mm, 1700 N / mm, 1800 N / mm, 1900 N / mm, 2000 N / mm, 2100 N / mm, 2200 N / mm, 2300 N / mm, 2400 N / mm, 2500 N / mm, 2600 N / mm, 2700 N / mm, 2800 N / mm, 2900 N / mm, 3000 N / mm, 3100 N / mm, 3200 N / mm, 3300 N / mm, 3400 N / mm, 3500 N / mm, 3600 N / mm, 3700 N / mm, 3800 N / mm, 3900 N / mm, 4000 N / mm, or the like, depending on the desired thickness, the type of powder particles used, or the like.

[0084] After compression by the calendering unit 126, the web 102 can be fed along direction 112 to a distal end of the system 100 (e.g., the downstream end) at which the web 102 is collected at a roller and / or spool. In some embodiments, the system 100 can incorporate one or more ultrasonic sources to apply ultrasonic vibration to the powder particles on the web 102. Such ultrasonic wave application to the powder particles can assist with deagglomeration and settling / leveling of the powder particles, ensuring uniformity in the powder particle layer. The ultrasonic wave application can assist with improved compaction and fusion of the particles relative to each other, thereby optimizing the resulting battery electrode structure and functionality.

[0085] As discussed herein, the powder particles deposited onto the web 102 with the deposition unit 114 travel towards the conditioning unit 118 for spreading along the web 102 surface. Due to the narrowed height of the nip 138 between the rollers 120, 122, powder particles accumulate directly upstream of the roller 120 and for an accumulation or mound. In particular, the roller 120 acts as a gate, dam or metering device, admitting only21MEl\60318381.vlAttorney Docket No. 137174.00112some amount of powder particles and the powder particles begin to form a rolling pile or mound in advance of the roller 120. The powder particle build-up can be thickest, highest and / or widest where incoming powder is greater, or in the center of the web 102 where the powder particles cannot easily self-redistribute. The variability in the powder particle build-up (e.g., mound) can result in inconsistencies (e.g., flaws, non-uniformities, or the like) in the powder particle layer created downstream of the conditioning unit 118.

[0086] To address the potential inconsistencies in the powder particle layer, the system 100 includes a powder modification unit 140 disposed immediately upstream of the conditioning unit 118. The modification unit 140 modifies or redistributes the powder particles in the mound to achieve a uniformity in the height, depth and / or width of the mound upstream of the roller 120, resulting in higher uniformity of the powder particle coating downstream of the roller 120. It should be understood that one or more of the modification units 140 discussed here can be used with the system 100 for achieving uniformity of the mound.

[0087] In some embodiments, the modification unit 140 can include one or more components that automatically engage with the powder particles after the mound has reached a predetermined height, depth and / or width. For example, the modification unit 140 can operate continuously and may immediately engage with the powder particles comprising the mound as the powder particles reach (or exceed by a defined amount) the predetermined height, depth and / or width. It should be understood that the height, depth and / or width of the mound maintained by the modification unit 140 can vary depending on, e.g., the types of powder particles being used, the equipment of the system 100, the final electrode and / or coating specifications, combinations there, or the like. As such, the examples for height, depth and / or width provided herein are non-limiting. According to some embodiments, the preferred width maintained by the modification unit 140 can be generally less than or equal to the width of the desired finished coating, the depth can be between about 100 um - 50 mm, and the height can be less than about 20 mm. According to some embodiments, an automatic engagement of the modification unit 140 may be triggered by a determined geometric ratio. A determined geometric ratio may include a height of the powder pile (e.g., mound) in relation, or relative to, a height of the incoming powder, a height of the powder downstream of the roller nip, a height (or radius) of the roller, a width of the mound, or a length of the mound.

[0088] According to some embodiments, a variation in a property of a mound can 22MEl\60318381.vlAttorney Docket No. 137174.00112trigger operation of the modification unit 140. A variation in a property of the mound can include, e.g., a width of the mound falling below or exceeding a target value or set of values, a height of the mound falling below or exceeding a target value or set of values, a length of the mound falling below or exceeding a target value or values, or combinations thereof.

[0089] In some embodiments, operation of the modification unit 140 can be triggered by a variation metric of a set of measurements at different locations along a mound. A variation metric can include, e.g., a standard deviation of a set of measurements, a variance of a set of measurements, a range (greatest less smallest) of a set of measurements, any other method of characterizing a variation inherent in a collection of measured data corresponding to a mound property, or combinations thereof. For example, and according to some embodiments, a series of height measurements along a mound may be used to compute a standard deviation in height and the standard deviation in height may be compared against at least one reference standard deviation to trigger an action to modify the mound.

[0090] In some embodiments, the modification unit 140 can be selectively operated to modify the powder particles associated with the mound based on, e.g., instructions received from a controller 142 which receives sensor 144 readings regarding characteristics associated with the mound. The controller 142 and sensor 144 can form a feedback loop of the system 100.

[0091] In some embodiments, the sensor 144 can be, e.g., beta particle. X-ray, Terahertz, infra-red, non-contact reflection, diffraction, spectroscopy, optical thickness measurement, acoustic transmission, combinations thereof, or the like. In some embodiments, the sensor 144 data can be transmitted to the deposition unit 114 to modify operation of the deposition unit 144 with the controller 142, e.g., to selectively reduce or increase the amount of powder deposited on the web 102 based on the mound variability, thereby assisting with reduction of the mound variability or inconsistency.

[0092] The modification unit 140 can redistribute and / or modify the powder particles of the mound without disturbing new incoming powder particles, e.g., powder particles below the threshold height, depth and / or width. The modification unit 140 can redistribute the powder particles located over the threshold height, depth and / or width across the web 102 to create a mound with substantially uniform height, depth and width along the roller 120. Such uniform mound ensures that the roller 120 face has a substantially even or equal23MEl\60318381.vlAttorney Docket No. 137174.00112amount of powder particles across the entire face, resulting in higher uniformity in the powder particle coating downstream of the roller 120. The modification unit 140 can continuously maintain the uniformity of the mound (e.g., the geometry uniformity, profile uniformity, or any other property of the powder of the mound), which can optionally be assisted by control of the incoming powder mass from the deposition unit 114.

[0093] FIG. 8 is a diagrammatic, detailed view of the system 100, specifically showing the conditioning roller 120 relative to the web 102. The lower roller 122 of the conditioning unit 118 and the modification unit 140 have been omitted for clarity. An initial powder particle coating 146 is applied to the web 102 by the deposition unit 114 and fed to the conditioning roller 120. The coating 146 can have an initial thickness or height 148 (e.g., Pti), as measured from the top surface of the web 102. In some embodiments, the initial thickness (Pti ) can range from about 0-5 mm, inclusive. The nip 138 defines a gap height 150 through which the powder particles are fed and spread or otherwise conditioned by the roller 120. The gap height (Ghi ) can be controlled as a function of incoming thickness (Pti ), where (Pti - Ghi) ranges from about 0 mm to 0.5*7? / , where Ri is the radius of the conditioning roller. Downstream of the roller 150, e.g., after conditioning, a conditioned powder particle coating 152 is achieved. The coating 152 defines a thickness or height 154 (e.g., PG), as measured from the top surface of the web 102. The height 154 is smaller than the height 148. The height difference 156 defines the delta between the two heights 148, 154, and represents the height of the powder particles spread or redistributed by the roller 120. The difference between the height 154 and the gap height 150 (i.e., Pt? - Ghi) represents a springback value, e.g., the height that the powder particles rise after passage through the nip 138 which may occur as a result of compression of the powder which has interacted with the roller 120. Other characteristics of the powder particle coating upstream and downstream of the roller 120, as well as characteristics of the roller 120, can be as follows:Pti = Powder layer thickness after depositionVT - Tip or surface speed of conditioning roller Ghi = Gap height between conditioning roller and web Pt? = Powder layer thickness downstream of conditioning rollervw = Linear velocity' of web24MEl\60318381.vlAttorney Docket No. 137174.00112Ph - Modification unit (e.g., plow) height above the web (see height 210, FIG. 11) Gd = Gap distance between modification unit (e.g., plow) and conditioning roller Td = Distance traveled by modification unit (e.g., plow)Ri= Radius of conditioning rollerIt is noted that that the tip or surface speed (vrf) of the conditioning roller 120 can be in the direction shown, or in the reverse direction. The tip, surface or rotational speed of the lower roller 122 disposed below the web 102 can be the same or different from the tip, surface or rotational speed of the roller 120.

[0094] Ph is above the Pti peaks, but below the heights of the powder pile build-up before the conditioning roller 158. These potential values can change depending on, e.g., the incoming powder pile, the desired amount of redistribution needed, the Td value, the head design, combinations thereof, or the like. In some embodiments, the heights can be between about 225 um to 10,000 um, inclusive. In some embodiments, Pti can be about, e.g., 100 um to 500 um, inclusive. In some embodiments, vr1can be about, e.g., 0-100 m / min, inclusive, in either direction. In some embodiments, Ghi can be about, 50 um up to 1 mm, inclusive. In some embodiments, Pt2 can be, e.g., as low as 50 um, up to 1 mm, or the like. In some embodiments, vw can be about, e.g., 1-100 m / min, or the like. In some embodiments, Ph can be about, e.g., 0 mm up to 0.5* roll diameter (R , or the like. In some embodiments, Gd can be about, e.g., 0.1-20 mm, inclusive, or the like. In some embodiments, Td can be about, e.g., 0.1-400 mm, inclusive, or the like. The maximum value of Td can be as wide as the maximum foil width being used). In some embodiments, Ri can be about, e.g., 35-200 mm, inclusive, up to 3,000 mm, or the like. It should be understood that the ranges and values provided herein are non-limiting and are provided only for example purposes.

[0095] FIG. 9 is a diagrammatic, detailed view of the system 100, including the conditioning roller 120 and a mound 158 formed of powder particles 164 immediately upstream of the roller 120. It should be noted that the particles 164 shown in FIG. 9 are not necessarily drawn to scale, and are provided for illustration purposes only. An initial powder particle coating 160 is dispensed onto the web 102 via the dispending unit 114. As the web 102 is passed under the roller 120, powder particles gather directly upstream of the roller 120 and against the upstream face of the roller 120. While the coating 160 can define a preferred height (measured along the z axis), the height of the mound 158 is above the 25MEl\60318381.vlAttorney Docket No. 137174.00112coating 160 height. The mound 158 defines a depth measured along the y-axis, and a width measured along the x-axis extending perpendicularly to the direction 112 and the roller 120. The mound 158 can have inconsistencies in one or more of the height, depth and / or width along the upstream face of the roller 120. Due to these inconsistencies, different amounts of powder can pass under the roller 120 along its length, resulting in inconsistencies or flaws in the downstream powder particle coating 162.

[0096] FIG. 10 is a diagrammatic, top view of the system 100, including a powder modification unit 200 in the form of a “powder plow’’. In particular, FIG. 10 illustrates the roller 120 disposed over the web 102, and a mound 158 of powder particles formed immediately upstream of the roller 120. In the view of FIG. 10, the depth of the mound 158 is measured along the y axis, and the width of the mound 158 is measured along the x axis. The modification unit 200 a stationary rail 202 extending over and across the entire width of the web 102. The rail 202 is disposed upstream of the mound 158 and does not itself engage with or contact the powder particles on the web 102.

[0097] An exemplary modification unit 200 includes a powder plow 204 (e.g., mover, blade, or the like) movably or slidably coupled to the rail 202. The plow 204 is actuated to continuously or selectively slide along the rail 202, with the plow 204 engaging with portions of the mound 158 located above a predetermined height to redistribute the powder particles. Engagement of the plow 204 with the mound 158 maintains the mound 158 at the desired predetermined height, and redistributes any powder particles above the predetermined height along the width and depth of the mound 158, thereby achieving uniformity in each of the height, depth and width of the mound 158.

[0098] In particular, the plow 204 manipulates the powder particle built-up on the web 102 in front of the roller 120 which is rotating relative to the web 102 at a lower height than the incoming powder. The plow 204 is attached to the linear rail 202 to constrain the motion travel of the plow 204 to the rail 202. The linear rail 202 is a substantially straight, mechanical element aligned in a cross-web direction (perpendicular to the direction of travel of the web 102). The plow 204 is further operated upon by an actuator to actuate the plow 204 along the rail 202. In some embodiments, the linear actuator can include the rail 202 or other methods of motion constraint. In some embodiments, the actuator can be, e.g., a linear motor, a linear stage, a linear rail, a linear guide, a linear rod, combinations thereof, or the like. The plow 204 is thus configured and controlled to move along the web 102 perpendicular to the web 102 path (i.e., direction 112). More generally, the rail 202 and the 26MEl\60318381.vlAttorney Docket No. 137174.00112direction of travel of the plow 204 may be aligned with the central axis of the roller 120 such that the travel of the plow 204 is aligned with the central axis of the roller 120. Thus, in some embodiments, the plow 204 travels in a direction substantially parallel to the axis of the roller 120, with the bottom edge of the plot 204 remaining substantially parallel and equidistant from the web 102 along the entire lateral travel path over the web 102. The plow 204 travels to specified end locations of the rail 202 (which extend at least the width of the web 102) to redistribute the powder on the web 102 effectively. The plow 204 includes a configuration complementary to the upstream face of the roller 120 (e.g., curved or semi-circular). This configuration allows the plow 204 to be positioned immediately adjacent to, but not touching, the roller 120 face, thereby engaging powder particle buildup in the mound 158 up to the roller 120 itself.

[0099] The bottom edge of the plow 204 defines the predetermined height at which the mound 158 is to be maintained. The bottom edge of the plow 204 is offset from the incoming powder particle height (e.g., height 148 in FIG. 8) in order to prevent disruption of the desired powder particle coating height, but is disposed below the initial height of the mound 158 to reduce the mound 158 height to the desired level. The mound 158 height is therefore reduced by the plow 204 to a height between the incoming powder particle height for the overall web 102 coating layer, and the initial height of the mound 158.

[0100] In general, powder particle build-up can be greater at or near the center of the web 102, e.g., with a higher mound 158 height towards the center of the web 102 at the roller 120, as compared to other locations along the roller 120. However, the mound 158 can also have peaks of high non-uniformity across the width of the roller 120. As the plow 204 slides side-to-side across the rail 202, the plow 204 effectively moves powder particles 158 from only the mound 158 to the edges or valleys of non-uniformity. The plow 204 therefore redistributes the powder particles in the mound 158 only without contacting the surrounding powder particles on the web 102 to achieve uniformity in the height, depth and width of the mound 158. Such uniformity of the powder particle mound 158 dispersed against the conditioning roller 120 acts as a reservoir for the conditioning roller 120 to draw from, providing uniformity downstream of the roller 120 as well. In particular, the mound 158 acts to fill in areas of continuous or intermittent low spots on the incoming web 120, as well as reducing excessive build-up that may unfavorably pack more powder and decrease uniformity. As a result, the level of powder particles entering the nip 138 is27MEl\60318381.vlAttorney Docket No. 137174.00112uniform, resulting in uniformity in conditioning and the downstream powder particle coating 162 layer.

[0101] FIG. 11 is a detailed, side view of the system 100 of FIG. 10, including the modification unit 200. The desired incoming powder particle height is represented by height 206 as measured from the web 102 surface along the z axis. The initial mound 158 height can be represented by height 208. As the plow 204 moves across the width of the web 102, the bottom edge of the plow 204 engages with and redistributes the powder particles of the mound 158 to achieve the reduces, predetermined mound height 210. The resulting mound height 210 can thereby be maintained by the modification unit 200 at the height 210, which is between the height 206 of the incoming powder particles and the initial height 208 of the mound 158. As the powder particles are distributed by the plow 204, uniformity in the depth (as measured along the y axis) and the width (as measured along the x axis) is also achieved.

[0102] FIG. 12 is a perspective view of the system 100 including a modification unit 220 substantially similar to the modification unit 200, except for the distinctions noted herein. The modification unit 220 also includes a plow 222 configured to engage with the mound 158 formed upstream of and at the face of the roller 120. The modification unit 200 includes a support beam 224 extending across the web 102 and includes an actuation mechanism in the form of a linear slide including the rail 226 and a screw 227 (e.g., at least partially supported by the support beam 224). The rail 226 and the screw 227 extends at least the width of the web 102 along a direction parallel to the central longitudinal axis of the roller 120. The rail 226 is spaced from the upstream face of the roller 120.

[0103] The modification unit 220 includes a block 228 including an opening or carriage complementary to the rail 226 such that the block 228 can be actuated to slide along the rail 226. In some embodiments, the bottom edges of the block 228 can contact the support beam 224 to maintain a uniform orientation of the block 228 as the block 228 slides along the rail 226. The screw 227 can be threaded and passes through a complementary threaded opening in the block 228. A nut in the block 228 is constrained from rotation, while allowing the block 228 to translate linearly along the rail 226. Thus, a motor can actuate rotation of the screw 227, which pulls and translates the block 228 along the rail 226. By actuating the screw 227 to rotate clockwise or counter-clockwise, the forward and backward linear motion of the block 228 (and the plow 222) is achieved. An interconnecting bar 230 can couple to the block 228 at one end, and couples to the plow 28MEl\60318381.vlAttorney Docket No. 137174.00112222 at the opposing end. The interconnecting bar 230 allows the plow 222 to be mounted immediately upstream of the roller 120, such that the front face 232 of the plow 222 (which defines a shape complementary to the face of the roller 120) engages powder particles in the mound 158 in contact with the face of the roller 120. A bottom edge 234 of the plow 222 contacts the mound 158 and redistributes powder particles of the mound 158 as the plow 222 is actuated to slide side-to-side along the rail 226. The height of the bottom edge 234 relative to the web 102 can be adjusted using fasteners 236, which couple the plow 222 to the end of the interconnecting bar 230. In some embodiments, the height of the bottom edge 234 can be automatically adjusted using a mechanical or electrical system.

[0104] FIGS. 13-15 are perspective, rear and side views of the modification unit 222 of FIG. 12. The block 228 can include a channel, cutout, or passage 238 into which one end of the interconnecting bar 230 is positioned and fastened. The interconnecting bar 230 can include, in some embodiments, a first horizontal section 240 extending parallel to the web 102, a vertical section 242 extending perpendicularly to the web 102 and the section 240, and a second horizontal section 244 extending parallel to the web 102 an the section 240. The interconnecting bar 230 allows for the block 228 to slide along the rail 226 at a distance higher from the web 102, while mounting the plow 222 closer to the web 102 for engagement with the mound 158. It is envisioned that other configurations of the interconnecting bar 230 could be used to achieve a similar result.

[0105] In some embodiments, the rear edge 246 of the plow 222 can extend perpendicularly relative to the web 102. In some embodiments, the plow 222 can include a gradually thinning or tapered bottom section 248 (relative to an upper section 250 mounted to the bar 230), which provides greater flexibility in the bottom section 248 and along the entire bottom edge 234 of the plow 222. The flexibility may reduce the rigidity of engagement of the plow 222 with the powder particles of the mound 158. In some embodiments, the entire plow 222 can remain rigid and the tapered bottom section 248 can be provided for a concrete area to be in contact with the powder particles of the mound 158. In some embodiments, the tapered configuration advantageously provides a leading angle of the powder plow 222 to either compact or push more material along its path. In some embodiments, the plow 222 can define a curved or plow-like shape to lift and hold the powder particles to impact the distance at which the powder id redistributed. The geometry of the plow 222 can therefore be designed to either push material up and out of the way, compact the powder material, or push the material generally. The plow 222 can therefore29MEl\60318381.vlAttorney Docket No. 137174.00112operate similarly to a screen (used during the making of an asphalt road), vs a common plough used in soil tilling. The front face 232 of the plow 222 is concave or inwardly curved to be complementary to the upstream face of the roller 120. The front face 232 can define a continuous curvature up to the endpoint 252.

[0106] The plow of the modification unit 220 can define various configurations, which are illustrated in the perspective and side views of FIGS. 16-21. FIGS. 18-19 show the plow 222 of FIG. 15, including the front face 232 defining a substantially continuous curvature complementary to the face of the roller 120. A top surface of the plow 222 includes openings 254 configured to engage with the fasteners 236 for coupling to the bar 230.

[0107] FIGS. 16-17 show a plow 260 substantially similar to the plow 222 of FIGS.18-19, except that the front face 262 of the plow 260 only partially defines the inwardly curved configuration and a section 264 extends from the curved face 262 to the endpoint 266. The section 264 generally defines a linear projection from the end of the curved face 262, with the top surface of the section 264 extending substantially parallel to the bottom edge 234. The linear projection formed by the section 264 aids in standing off or offsetting the plow 260 from the roller 120 as to not disturb material immediately entering the nip, but able to still redistribute the bulk of the powder particles in the mound. The tall height of the wall or endpoint 266 relative to the bottom edge 234 allows quicker settings of gap and distance against the roller 120 when assembling.

[0108] FIGS. 20-21 show a plow 270 substantially similar to the plow 22 of FIGS. 18-19, except that the front face 272 of the plow 270 is not inwardly curved. Rather, the plow 270 includes a linearly angled front face 272 that extends at an angle from a vertical linear section 274 at one end and connects with a linear horizontal section 276. The section 274 extends perpendicularly relative to the bottom edge 234, and the section 276 includes a top surface extending parallel to the bottom edge 234 up to the endpoint 252. The side surfaces of the plow 270 can include an upper section 250 with parallel opposing sides, an intermediate section 278 with inwardly tapered side walls (thereby reducing the overall thickness of the plow 270), and a bottom section 280 with parallel opposing sides up to the bottom edge 234. The lengths and configuration of the plow 270 allow for powder to be pushed outwards in limited quantity where powder supply is abundant, but not redistribute the bulk of the powder. The plow 270 can constrain larger piles or mounds from30MEl\60318381.vlAttorney Docket No. 137174.00112distributing too much powder to the edges, which could lead to web 102 rips or unfavorable powder distribution.

[0109] FIG. 22 is a diagrammatic view of the system 100, including a modification unit 300 in the form of multiple powder plows 302. In particular, the system 100 of FIG.22 includes a stationary rail 304 extending across the width of the web 102. The system 100 includes one or more powder plows 302 slidably positioned on the same rail 304. In some embodiments, each of the plows 302 can traverse only a portion of the length of the rail 304, thereby covering an equal distance to the other plows 302. In some embodiments, the paths of the plows 302 can incrementally overlap to ensure all powder particles are uniformly redistributed between the plows 302.

[0110] In some embodiments, each of the plows 302 can be actuated simultaneously to operate in the sliding motion along the lateral direction 306 perpendicular to the web 102 moving direction 112. In some embodiments, each of the plows 302 can be individually actuated to traverse laterally along direction 306 only along its respective portion of the rail 304. For example, the feedback loop of the system 100 can be used to determine which portion of the mound 158 requires redistribution, and the corresponding plow 302 can be actuated to modify the mound 158 and redistribute the powder particles. Thus, one or more plows 302 can move laterally while the other plows 302 remain stationary until future actuation. Using multiple plows 302 enables a higher response resolution for redistribution of the powder particles at the mound 158, since the stroke of motion can be reduced and a larger areal coverage can be achieved through the distributed plows 302. In particular, upon detection of mound 158 non-uniformities, the system 100 can actuate the plow 302 closest to the detected non-uniformity to engage with and redistribute the powder particles to achieve uniformity. The non-uniformity can therefore be potentially resolved in a lower period of time than if a single plow was used.

[0111] FIG. 23 is a diagrammatic view of the system 100, including a modification unit 350 in the form of rotary plows 352. In some embodiments, the rotary plows 352 can be convey or- actuated powder plows, or the like. For example, the system 100 can include one or more circuits 354 (e.g., belts, conveyors, or the like) along which multiple powder plows 356 can be mounted. The circuit 354 can be continuously or selective actuated to rotate via a signal from a controller such that the plows 356 intermittently interact with the powder particles of the mound 158.31MEl\60318381.vlAttorney Docket No. 137174.00112

[0112] In some embodiments, as shown in FIG. 23, the system 100 can include two rotary plows 352 disposed adjacent to each other such that each rotary plow 352 covers at least half of the web 102 surface. The rotary plows 352 are laterally disposed over the web 102 with an overlap in the powder plows 356 at the central area of the web 102. The rotary plows 352 can be actuated to rotate in opposing clockwise and counterclockwise directions 358, 360, thereby moving and redistributing the powder particles outward from the center of the web 102 towards the edges. In some embodiments, the rotary plows 352 can be actuated to rotate in opposing directions from those shown in FIG. 23, allowing for inward movement and redistribution of the powder particles towards the center of the web 102. The speed of rotation of the rotary plows 352 can be adjustable, and the configuration of FIG. 23 can be used for highly variable powder mounds, for the example.

[0113] FIG. 24 is a diagrammatic view of the system 100, including a modification unit 400 in the form of a rotating auger 402. In particular, the system 100 of FIG. 24 includes an auger blade 404 selectively rotatable in either direction along a central axle 406, which is mechanically coupled to a drive motor 406. The auger blade 404 edge (e.g., the plane defined by the auger blade 404 edge) defines the predetermined height desired for the modified mound 158, and the distance of the auger blade 404 from the web 102 can be modified based on the desired mound 158 height.

[0114] The drive motor 406 can receive signals from the controller regarding detection of the mound 158, including instructions for which direction to rotate the auger blade 404. In some embodiments, the system 100 can include a sensor 408 disposed upstream of the modification unit 400 and configured to detect non-uniformities in the mound 158. In some embodiments, the sensor 408 can extend along the entire width of the web 102. The sensor 408 can transmit signals to the drive motor 406 for selective actuation of the drive motor 406.

[0115] The rotating auger 500 is therefore used to modify the mound 158 height, depth and / or width by moving and redistributing the powder particles. Motion of the powder particles along the auger blade 402 can be controlled by the relative motion between the blade 402 surface and the powder particles in contact with the blade 402. The auger 400 can be specified by the radii of the auger blade 402 (e.g., an innermost and outermost diameter), a thickness of the blade 402, a blade 402 geometry (e.g., blade profile, such as a knife-edge), a blade 402 angle, a blade 402 spacing (e.g., pitch), or the like. The auger 400 can be specified with a handedness to auger blade 402 orientation, such that the auger 40032MEl\60318381.vlAttorney Docket No. 137174.00112can be configured in a right-handed screw configuration or a left-handed screw configuration. A right-handed screw configuration can result in a right-to-left motion for a clockwise rotary motion of the drive motor 406, while a left-handed screw configuration can result in a left-to-right motion for a clockwise rotary motion of the drive motor 406.

[0116] In some embodiments, the auger 400 can exhibit a mixture of right-handed and left-handed features along the surface of the auger blade 402 (e.g., screw features, auger blade features, curved elements, elements otherwise arranged at an angle relative to the surface normal of the web, combinations thereof, or the like). The features can be arrayed axially and radially. In some embodiments, the auger 400 can be segmented in some regions to exhibit differences in pitch, such that for the same rotary motion of the auger 400, different linear motion of the powder particles in contact with the auger blade 402 surface can result (e.g., a greater distance traveled for a greater distance between blades). In some embodiments, the segments can be arranged axially and / or radially. Thus, different auger blades 402 and / or segmentation can be used to achieve greater or less redistribution / movement of the powder particles from the mound 158.

[0117] In some embodiments, the auger 400 can be configured to rotate at a constant rate of rotation. In some embodiments, the auger 400 can be configured to rotate with an oscillatory rate of rotation, such that there is no net angular displacement of the auger 400 when averaged over time. In some embodiments, the auger 400 can be configured to rotate at a constant rate of rotation with a time-varying rate of rotation superposed on the constant rate of rotation. In some embodiments, the time -varying rate of rotation can be oscillatory. In some embodiments, the oscillatory time-varying rate of rotation can be cyclic (e.g., circular, sinusoidal, or the like). In some embodiments, the cyclic rate of rotation can be in a range from about, e.g., 0.1 Hz to 10 Hz inclusive, 5 Hz to 60 Hz inclusive, 50 Hz to 200 Hz inclusive, 150 Hz to 500 Hz inclusive, beyond 250 Hz, or the like.

[0118] In some embodiments, the auger 400 can be configured to undergo an axial motion in addition to a rotary motion. The axial motion can produce a motion of the auger 400 along the axis of the auger 400 (e.g., movement perpendicular to the web). An axial motion can be produced by a linear motor or other actuator. In some embodiments, the linear displacement of the auger 400 can be time-varying and can include motion in alternating directions to provide net zero displacement of the auger 400 over time. For example, the axial motion can produce a first displacement of the auger 400 in a first direction and a second displacement of the auger 400 in a second direction, where the 33MEl\60318381.vlAttorney Docket No. 137174.00112magnitudes of the first and second displacement are equivalent and the second direction is opposite the first. In some embodiments, the displacement can be non-equivalent, depending on the distance or unit for the push / pull operation. For example, a reference position can be established about which the axial motion is referenced. A positive distance can be considered a “push”, and a negative distance can be considered a “pull”. As an example for non-equivalent displacement, the push can be performed by 1 unit, returned to zero, and then pull is performed by 0.5 units, with oscillation with the motion. This motion can therefore be similar to a sin wave, which is biased above or below zero.

[0119] In some embodiments, the auger 400 can be operated in a back and forth motion, oscillating the movement of the powder particles back and forth in the cross-web direction. In some embodiments, the motion can be continuous. In some embodiments, the motion can be selective or strategic to remove some amount of powder particles by driving the powder particles off the edge of the web 102 and into a reclaim system.

[0120] FIG. 25 is a diagrammatic view of the system 100, including a modification unit 450 in the form of sonotrode 452 (e.g., a vibration horn). The sonotrode 450 can be disposed over the mound 158 and extends at least the width of the web 102. A sensor 454 can be disposed upstream of the sonotrode 452 to detect characteristics of the mound 158, e.g., non-uniformities, or the like. The sonotrode 452 can be actuated to create vibrations within the powder mound 158 and / or the surrounding air (which translates to the powder mound 158) to enable modification of the powder mound 158.

[0121] In some embodiments, the sonotrode 452 can be a single vibration horn extending across the web 102 and discretely controlled to create a vibration profile along the entire web 102. In some embodiments, the sonotrode 452 can be in the form of an assembly built of smaller discrete sonotrodes, which can be individually selectively controlled to create a vibration profile along the web 102 width. The vibration field can be used to fluidize powder particles out of the mound 158 and then brought to a reclaim system, such as a vacuum, to remove powder particles (if needed).

[0122] FIG. 26 is a diagrammatic view of the system 100, including a modification unit 500 in the form of an air manifold 502. The air manifold 502 can be in the form of a hollow tube extending over the mound 158. The air manifold 502 includes spaced orifices 504 along its length and along the width of the web 102. One end (or both ends) of the air manifold 502 can be connected to an air source 506 configured to selectively supply air34MEl\60318381.vlAttorney Docket No. 137174.00112508 to the air manifold 502. In some embodiments, all orifices 504 can be opened or closed together. In some embodiments, the orifices 504 can be selectively opened or closed such that air is directed towards the mound 158 in a selective manner, thereby engaging with and modifying / redistributing the powder particles in specific locations. The system 100 can include a sensor 510 disposed over the web 102 upstream o the air manifold 502 and configured to detect characteristics associated with the mound 158. Signals from the sensor 510 can be used to operate the modification unit 500 to supply air in areas detected to have non-uniformities (e.g., for high points of the mound 158) or in areas around the nonuniformities (e.g., for low points of the mound 158).

[0123] The orifices 504 are therefore distributed to selectively release air onto the powder mound 158 to enable modification and motion of the powder particles in the mound 158. The distributed orifices 504 can be positioned in different locations in reference to the powder mound 158. For example, the orifices 504 can be vertically above, horizontal, or in any position in-between (e.g., any radial position along the hollow tube). In some embodiments, the orifices 504 can be distributed at various radial angles or directions, rather than a single orifice 504 laterally offset from other orifices 504. In some embodiments, the orifices 504 can define different geometric designs to enable specific profiles of air to be released (e.g., round nozzles, flat fan nozzles, conical nozzles, bullet nozzles, adjustable gallonage nozzles, combinations thereof, or the like). The pressure drop across the orifice 504 can be controlled by the incoming air 508 supply, the orifice 504 geometry, and the degree of opening. In some embodiments, the air 508 release can be used to remove powder particles by blowing them out of the mound 158 and into a reclaim system, such as a vacuum.

[0124] FIG. 27 is a diagrammatic view of the system 100, including a modification unit 550 in the form of an electrode charging unit 552. The charging unit 552 can be disposed over the mound 158 and extends the width of the web 102. A sensor 554 disposed upstream of the charging unit 552 can detect characteristics associated with the mound 158, and transmits signals to the charging unit 552 for selective operation to modify the powder particles associated with the mound 158. The charging unit 552 can be a charging electrode placed in proximity to the powder mound 158 to strategically charge and mobilize the powder particles using alternating current (AC) electric fields. In particular, the charging unit 552 can selectively charge the powder particles such that the powder particles are actuated to move from one area of the mound 158 to another area of the mound 158 to35MEl\60318381.vlAttorney Docket No. 137174.00112achieve uniformity of the mound 158 height, depth and / or width. The AC electric fields can utilize a variety of waveforms including, but not limited to, e.g., sine waves, square waves, triangle waves, sawtooth waves, pulses, or the like. In some embodiments, the AC electric fields can be used to lift powder particles out of the mound 158 and transfer the powder particles to a reclaim system, such as a vacuum, to remove powder particles (if needed).

[0125] FIG. 28 is a diagrammatic view of the system 100, including a modification unit 600 in the form of a selective powder dispersion assembly 602. The powder dispersion assembly 602 can be in the form of a tube configured to transfer powder particles from a powder source. The powder source can be shared with the powder deposition unit 114 of FIG. 7, or can be a similar dedicated powder source. The assembly 602 can include multiple discrete deposition areas 604 spaced along the length of the assembly 602. The areas 604 can be openings which can be selectively opened or closed, or can be any of the deposition types discussed with respect to the powder deposition unit 1 14.

[0126] In operation, the system 600 can include a sensor 606 disposed upstream of the modification unit 600 to detect characteristics associated with the mound 158. If nonuniformities in the mound 158 are detected in the form of low points, the modification unit 600 can be actuated to selectively add powder particles to the mound 158 in specific locations to reduce or prevent the low points. The discrete powder feeding mechanisms can include, but are not limited to, e.g., brush feeders, screw feeders, spray nozzles, electrostatic powder feeders, vibratory tables, belt conveyors, combinations thereof, or the like. In some embodiments, the discrete powder feeding can be one unit 600 which adds powder particles across the entire web 102 width. In some embodiments, the discrete powder feeding can be an array of specific powder feeding locations (e.g., at each of areas 604).

[0127] FIG. 29 is a diagrammatic view of the system 100, including a modification unit 650 in the form of a selective powder removal assembly 652. The removal assembly 652 can include a tube extending over the mound 158 and across the web 102. One end of the tube is connected to a vacuum source 654 (or any other known powder removal source). The tube includes multiple spaced orifices 656 along its length which can be selectively opened or closed to allow for suction of powder particles therethrough. A sensor 658 can detect high points of the mound 158 and transmits signals to the modification unit 650 to36MEl\60318381.vlAttorney Docket No. 137174.00112selectively open the orifices 656 over the high points to suction powder particles from the mound 158 until uniformity in the mound 158 height is achieved.

[0128] The modification unit 650 can therefore be used to selectively remove powder particles out of the mound 158 using a vacuum to modify the powder mound 158. The orifices 656 can be at discrete locations and individually controlled to regulate the amount of powder particles removed at each location. In some embodiments, the powder removal system can be a single unit which spans the web 102 width to remove a bulk powder across the mound 158. In some embodiments, the distributed orifices 656 can be positioned in different locations in reference to the powder mound 158. For example, the orifices 656 can be vertically above, horizontal, or in any position in-between (e.g., any radial position along the hollow tube). In some embodiments, the orifices 656 can be distributed at various radial angles or directions, rather than a single orifice 656 laterally offset from other orifices 656.

[0129] FIG. 30 is a diagrammatic view of a system 700 for dry powder coating. The system 700 can be substantially similar to the system 100, except for the distinctions noted herein. The system 700 includes a web 702 moving in a web direction 704 under a conditioning roller 706 (e.g., a conditioning unit). The web 702 has an initial particle powder coating 708 on the top surface of the web 702. The web 702 defines a lateral width dimensioned as the distance between opposing lateral edges 710, 712 of the web 702. The lateral width defines the cross-direction perpendicular to the web direction 704. The coating 708 can be formed such that uncoated strips or areas 714, 716 (e.g., lanes) exist along the length of the web 702 adjacent to the respective lateral edges 710, 712. After passage of the web 702 through the conditioning roller 706, a conditioned particle powder coating 718 is formed.

[0130] As the mound 720 of powder particles forms upstream of the conditioning roller 706, the powder particles of the mound 720 can spread laterally such that opposing edges or ends 722, 724 of the mound 720 extend beyond coating 708, onto the uncoated areas 714, 716, and up to the lateral edges 710,712 of the web 702. Such lateral spreading of the mound 720 can create inconsistencies in the uncoated areas 714, 716, requiring additional conditioning and powder removal downstream of the conditioning roller 706.

[0131] In some embodiments, the modification units discussed herein can include one or more stationary guides or fins mounted near the conditioning roller at or near the edge37MEl\60318381.vlAttorney Docket No. 137174.00112of the coated electrode. These guides or fins can be used to confine the edges of the powder layer to prevent or minimize lateral spreading (in the cross-direction). Confining the edges of the powder layer can enable more uniform build-up of the characteristic pile or mound across the width of the substrate upstream of the conditioning roller. This also allows for improved control of the characteristic height, depth, and width of the mound.

[0132] FIGS. 31-33 are diagrammatic views of the system 700, including a modification unit with lateral fins 750, 752 disposed adjacent to the conditioning roller 706 on the upstream side of the conditioning roller 706. In some embodiments, the fins 750, 752 can be substantially aligned with the boundary edges between the uncoated areas 714, 716 and the coating 708. In some embodiments, the lateral position of the fins 750, 752 can be offset relative to such boundary edges. The fins 750, 752 provide a barrier that provides a limit to how far the powder particles of the mound 720 can spread laterally. Thus, rather than laterally spreading to the edges 710, 712 of the web 702, the fins 750, 752 confine the opposing lateral ends 754, 756 of the mound 720. In particular, the fins 750, 752 prevent the powder particles of the mound 720 from escaping laterally to the sides of the web 702. Such confinement prevents or limits powder infiltration onto the uncoated areas 714, 716, and results in improved uniformity of the mound 720 characteristics.

[0133] FIG. 33 illustrates a side profile of the fin 750, although it should be understood that both fins 750, 752 can define a similar side profile. In some embodiments, the fin 750 can define a leading edge height 758 dimensioned complementary to a nip 760 height between the conditioning roller 706 and an underlying support surface or secondary conditioning roller 762. The fin 750 can define a trailing edge height 764 dimensioned greater than the leading edge height 758. The trailing edge height 764 is dimensioned greater than the height of the mound 720, ensuring that the fins 750, 752 confine and prevent lateral spreading of powder particles of the mound 720. In some embodiments, a front or top edge 766 of the fin 750 can be curved or otherwise complementary to the curvature of the conditioning roller 706, allowing the fin 750 to be disposed adjacent to the roller 706.

[0134] The initial particle powder coating 708 can define an initial thickness 768. As the web 702 is moved along the web direction 704 towards the conditioning roller 706, a mound 720 of powder particles forms immediately upstream of the conditioning roller 706. The fins 750, 752 confine lateral spreading of the powder particles of the mound 720, and one or more additional components of the modification units discussed herein can be used 38MEl\60318381.vlAttorney Docket No. 137174.00112in combination with the fins 750, 752 to the characteristics associated with the mound 720 (such as the height, depth and / or width of the mound 720). Use of the fins 750, 752 as part of the modification unit therefore provides improved control of the mound 720 characteristics and provides overall improved uniformity in coating of the web 702. After passage of the web 702 between the conditioning rollers 706, 762, the conditioned powder particle coating 718 defines a thickness 770 dimensioned smaller than the initial thickness 768.

[0135] The fins 750, 752 therefore function to confine the edges of the powder layer at the mound 720 to prevent spreading of the mound in the cross-direction. Confining the edges of the mound 720 creates a more uniform build-up of the mound 720. In some embodiments, the fins 750, 752 can conform to the shape of the conditioning roller 706. In some embodiments, the fins 750, 752 can define a front or top edge (adjacent to the conditioning roller 706) having a shape or configuration different from the face of the conditioning roller 706. In some embodiments, as illustrated in FIG. 33, the fins 750, 752 can be positioned such that the forward or leading edge is fully within the nip 760 point between the conditioning rollers 706, 762. In some embodiments, the fins 750, 752 can be positioned at a distance offset upstream from the nip 760 (e.g., about 20 mm, about 30 mm, about 40 mm, about 50 mm, about 60 mm, about 70 mm, about 80 mm, about 90 mm, about 100 mm, or the like).

[0136] In some embodiments, each fin 750, 752 can have a thickness of about, e.g., 0.1-10 mm inclusive, 0.1-9 mm inclusive, 0.1-8 mm inclusive, 0.1-7 mm inclusive, 0.1-6 mm inclusive, 0.1-5 mm inclusive, 0.1-4 mm inclusive, 0.1-3 mm inclusive, 0.1-2 mm inclusive, 0.1-1 mm inclusive, 0.1-0.5 mm inclusive, 0.5-10 mm inclusive, 1-10 mm inclusive, 2-10 mm inclusive, 3-10 mm inclusive, 4-10 mm inclusive, 5-10 mm inclusive, 6-10 mm inclusive, 7-10 mm inclusive, 8-10 mm inclusive, 9-10 mm inclusive, 0.1 mm, 0.5 mm, 1 mm, 2 mm, 3 mm, 4 mm, 5 mm, 6 mm, 7 mm, 8 mm, 9 mm, 10 mm, or the like.

[0137] In some embodiments, the fins 750, 752 can be maintained in a stationary position relative to the outer edges of the deposited coating layer (coating 708). In some embodiments, the system 700 can include an adjustment mechanism that automatically adjusts the lateral position of the fins 750, 752 to maintain a relative position to the edges 710, 712 of the web 702. For example, if the web 702 “walks” side-to-side during operation of the system 700, the adjustment mechanism can automatically move the fins 750, 752 to maintain the fins 750, 752 substantially aligned with the coating 708 edges.39MEl\60318381.vlAttorney Docket No. 137174.00112

[0138] In some embodiments, the fins 750, 752 can be angled relative to the web direction 704. For example, the leading edge or tip of the fins 750, 752 can be angled inward, pointing towards the center of the web 702. As another example, the leading edge or tip of the fins 750, 752 can be angled outward, pointing way from the center of the web 702. In some embodiments, the bottom edge of the fins 750, 750 can be positioned in contact with the surface of the web 702. In some embodiments, the bottom edge of the fins 750, 752 can be positioned vertically offset from the web 702 by a distance of, e.g., 0.1-5 mm inclusive, 0.1-4 mm inclusive, 0.1-3 mm inclusive, 0.1-2 mm inclusive, 0.1-1 mm inclusive, 0.1 -0.5 mm inclusive, 0.5-5 mm inclusive, 1-5 mm inclusive, 2-5 mm inclusive, 3-5 mm inclusive, 4-5 mm inclusive, 0.1 mm, 0.5 mm, 1 mm, 2 mm, 3 mm, 4 mm, 5 mm, or the like, to prevent defects or potential damage to the web 702 surface.

[0139] Although two fins 750, 752 are illustrated, it should be understood that any number of fins can be used to confine the lateral edges of the mound 720. For example, if multiple strips of powder are deposited onto the web 702 and separated by uncoated areas or lanes, multiple sets of fins 750, 752 can be used to control each mound individually. The fins 750, 752 are therefore usable to improve the overall mound 720 formation and uniformity upstream of the conditioning roller 706.

[0140] FIG. 34 is a perspective view of a system 800 for dry powder modification. The system 800 can be substantially similar to the system 700, except for the distinctions noted herein. The same reference numbers are therefore used to refer to the same structures. The fins 750, 752 can be mounted to an adjustment mechanism formed by lateral rods 802, 804. Fixation blocks 806 can be used to adjust and fixate the lateral position of the fins 750, 752 along the rods 802, 804 relative to each other and relative to the web 702. The intended confinement of the mound width can therefore be adjustable or customizable. The system 800 can include an adjustment mechanism 808 for automatically adjusting the lateral position of the fins 750, 752 during operation of the system 800, allowing for compensation for any “walk” or side-to-side motion of the web 702. FIG. 34 further illustrates a calendaring roller 810 disposed downstream of the conditioning roller 706.

[0141] The exemplary systems discussed herein therefore modify the powder particles of the mound to redistribute the powder particles, thereby achieving uniformity in the height, depth and / or width of the mound. Uniformity of the mound ensures that the level and mass of powder particles against the upstream face of the conditioning roller remains substantially equal along the width of the web.40MEl\60318381.vlAttorney Docket No. 137174.00112

[0142] In some embodiments, the exemplary systems can be combined with improvements to the material deposition process. The modification unit seeks to level and redistribute the powder particles to more favorably process through the conditioning roller. An improved material deposition system can be used to more controllably deposit a consistent and optimally shaped bed of powder on the web, which can further ensure uniformity in the mound formed upstream of the conditioning roller. In some embodiments, due to the nature of the powder’s flowability characteristics, the system can incorporate stationary diverters to redirect areas of increased height in powder particle formation to lower areas on the web.

[0143] While exemplary embodiments have been described herein, it is expressly noted that these embodiments should not be construed as limiting, but rather that additions and modifications to what is expressly described herein also are included within the scope of the invention. Moreover, it is to be understood that the features of the various embodiments described herein are not mutually exclusive and can exist in various combinations and permutations, even if such combinations or permutations are not made express herein, without departing from the spirit and scope of the invention.41MEl\60318381.vl

Claims

Attorney Docket No. 137174.00112CLAIMS:

1. A system for powder modification, the system comprising:a substrate including a surface to be coated with powder, the substrate moving in a direction from an upstream end to a downstream end;a powder deposition unit disposed over the surface of the substrate and configured to deposit the powder onto the substrate to form a powder coating on the substrate;a conditioning unit disposed downstream of the powder deposition unit and configured to condition the powder coating; anda modification unit disposed upstream of the conditioning unit and configured to modify a characteristic of a mound of the powder collected upstream of the conditioning unit.

2. The system of claim 1, wherein the powder deposition unit includes at least one of nozzles, rollers, dispensing tubes, mechanical feeders, or electrostatic powder feeders.

3. The system of claim 1, wherein the powder coating on the substrate defines an initial coating height measured from the substrate, the mound defines an initial mound height measured from the substrate, and the initial mound height is dimensioned greater than the initial coating height.

4. The system of claim 3, wherein the characteristic of the mound is the initial mound height, and the modification unit is configured to redistribute the powder of the mound to reduce the initial mound height to a modified mound height.

5. The system of claim 4, wherein the modified mound height is dimensioned greater than the initial coating height and less than the initial mound height.

6. The system of claim 1, wherein the characteristic of the mound is at least one of a height, a depth, or a width of the mound.

7. The system of claim 6, wherein the modification unit is configured to redistribute the powder of the mound to create uniformity in at least the height, the depth, or the width of the mound along an entire width of the substrate.42MEl\60318381.vlAttorney Docket No. 137174.001128. The system of claim 1, wherein the conditioning unit includes a roller disposed above the substrate and defining a nip through which the powder coating passes to be conditioned.

9. The system of claim 8, wherein the mound of the powder is disposed immediately upstream of the roller and is disposed against an upstream face of the roller.

10. The system of claim 1, wherein the modification unit includes a powder plow configured to slide along a rail extending across a width of the substrate, the powder plow including a bottom edge configured to engage with the powder of the mound to modify the characteristic of the mound.

11. The system of claim 10, wherein the powder plow includes a front face with a configuration complementary to an upstream face of a roller of the conditioning unit.

12. The system of claim 1, wherein the modification unit includes multiple powder plows configured to slide along a rail extending across a width of the substrate, each of the multiple powder plows including a bottom edge configured to engage with the powder of the mound to modify the characteristic of the mound.

13. The system of claim 1, wherein the modification unit includes a rotary plow assembly including multiple powder plows extending from a rotating circuit such that each of the multiple powder plows intermittently engage with the powder of the mound to modify the characteristic of the mound.

14. The system of claim 1, wherein the modification unit includes a rotating auger including an auger blade rotating along a central axis extending across a width of the substrate, the auger blade engaging with the powder of the mound to modify the characteristic of the mound.

15. The system of claim 1, wherein the modification unit includes a sonotrode disposed over the substrate and configured to generate vibrations to redistribute the powder of the mound to modify the characteristic of the mound.

16. The system of claim 1, wherein the modification unit includes an air manifold including orifices configured to be selectively opened or closed to expel air onto43MEl\60318381.vlAttorney Docket No. 137174.00112the mound to redistribute the powder of the mound to modify the characteristic of the mound.

17. The system of claim 1, wherein the modification unit includes an electrode charging unit configured to selectively charge the powder of the mound to redistribute the powder of the mound to modify the characteristic of the mound.

18. The system of claim 1, wherein the modification unit includes one or more fins configured to confine lateral spreading of the powder of the mound.

19. A system for powder modification, the system comprising:a substrate including a surface to be coated with powder, the substrate moving in a direction from an upstream end to a downstream end;a powder deposition unit disposed over the surface of the substrate and configured to deposit the powder onto the substrate to form a powder coating on the substrate;a conditioning unit disposed downstream of the powder deposition unit and configured to condition the powder coating, the conditioning unit including a roller disposed over the substrate and defining a nip through which the powder coating is passed for conditioning; anda modification unit disposed upstream of the conditioning unit and configured to redistribute the powder of a mound of the powder collected upstream of the roller of the conditioning unit to modify a characteristic of the mound.

20. A method of powder modification, the method comprising:moving a substrate from an upstream end to a downstream end, the substrate including a surface to be coated with powder;depositing the powder onto the substrate with a powder deposition unit disposed over the surface of the substrate to form a powder coating on the substrate;conditioning the powder coating with a conditioning unit dispose downstream of the powder deposition unit; andmodifying a characteristic of a mound of the powder collected upstream of the conditioning unit with a modification unit disposed upstream of the conditioning unit.44MEl\60318381.vl

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