KR102461087B1 - Method of Forming Alumina for an Electrochemical Cell Using a Plasma Ionization Process - Google Patents

Abstract

An evaporation source 102 is provided for forming a ceramic layer of a component of an electrochemical energy storage device. The evaporation source 102 includes a material source configured to evaporate a material, a gas supply configured to supply a process gas, and a plasma source 108 configured to at least partially ionize the process gas, the ceramic layer 52 comprising: , at least formed by the evaporated material and at least partially ionized process gas.

Description

Method of Forming Alumina for an Electrochemical Cell Using a Plasma Ionization Process

Embodiments of the present disclosure relate to methods, evaporation sources, and processing chambers for forming a ceramic layer of a component of an electrochemical energy storage device. Embodiments of the present disclosure relate, inter alia, to a method, an evaporation source, and a processing chamber for forming the cathode, anode, electrolyte, or separator of a lithium battery or Li-ion battery.

An electrical separator may be described, for example, as a separator used in batteries and other arrangements in which electrodes are separated from each other while maintaining ionic conductivity.

[0003] Typically, a separator comprises a thin porous electrically insulating material having high ionic porosity, good mechanical strength, and long-term stability to chemicals and solvents used in electrolytes of systems, such as batteries. In batteries, a separator generally completely electrically insulates the cathode from the anode. In addition, a separator is generally permanently resilient and follows motions within the system resulting from "breathing" of the electrodes as ions as well as external loads are incorporated and released.

[0004] In general, a separator may be involved in determining the lifespan and safety of a system in which the separator is used. For example, the development of rechargeable batteries has been significantly impacted by the development of suitable separator materials.

Specifically, separators for use in high-energy batteries or high-performance batteries can be very thin to ensure low specific space conditions and minimize internal resistance, and high to ensure low internal resistances. It can have porosity and can be lightweight to achieve a low specific weight of the battery system.

[0006] Separators typically include a ceramic layer that is porous to the ions of the battery. In the case of lithium batteries, the ceramic layer may be porous to lithium ions (Li-ions). However, the ceramic layers may not be completely porous. For example, the ceramic layer may contain metal atoms that are not fully bonded and may react with Li-ions during charging/discharging of a Li-ion battery. Accordingly, battery performance may be degraded.

[0007] In view of the above, embodiments described herein provide methods and systems for forming components of an electrochemical energy storage device that can overcome at least some of the problems in the art. aim to The present disclosure aims to provide methods and systems for forming components of an electrochemical energy storage device, which can increase the cycle life and charge transport (discharge/charge rates) voltage of the electrochemical energy storage device do it with

[0008] In view of the above, a method, an evaporation source, and a processing chamber for forming components of an electrochemical energy storage device are provided. Additional aspects, advantages, and features of the present application are apparent from the dependent claims, the detailed description, and the accompanying drawings.

According to an aspect of the present disclosure, a method for forming a ceramic layer of a component of an electrochemical energy storage device is provided. The method includes evaporating a material on a flexible substrate, supplying a process gas, and at least partially plasma ionizing and/or dissociating the process gas, wherein the ceramic layer comprises at least the evaporated material and formed by the at least partially ionized process gas.

According to an aspect of the present disclosure, an evaporation source for forming a ceramic layer of a component of an electrochemical energy storage device is provided. The evaporation source includes a material source configured to evaporate a material, a gas supply configured to supply a process gas, and a plasma source configured to at least partially ionize and/or dissociate the process gas, wherein the ceramic layer comprises at least: material and at least partially ionized and/or dissociated process gases.

According to an aspect of the present disclosure, a process chamber is provided. The process chamber includes an evaporation source, the evaporation source comprising a material source configured to evaporate a material, a gas supply configured to supply a process gas, and a plasma source configured to at least partially ionize and/or dissociate the process gas and the ceramic layer is formed by, at least, the evaporated material and the at least partially ionized and/or dissociated process gas. The process chamber further includes a substrate transport mechanism configured to transport the flexible substrate through the process chamber. The evaporation source is arranged relative to the substrate transport mechanism such that the ceramic layer is formed on the flexible substrate.

Examples also relate to apparatus for performing the disclosed methods, and include apparatus portions for performing the described method blocks. These method blocks may be performed by hardware components, by a computer programmed by suitable software, by any combination of the two, or in any other manner. Furthermore, examples according to the present application also relate to methods for operating the described apparatus. A method includes method blocks or acts for performing functions of an apparatus.

[0013] In such a way that the above-listed features of the disclosure may be understood in detail, a more specific description of the disclosure briefly summarized above may be made with reference to embodiments. The accompanying drawings relate to embodiments of the present disclosure and are described below.
1 shows a schematic diagram of an evaporation source for forming a component of an electrochemical energy storage device arranged in a processing chamber, according to embodiments;
2 shows a schematic diagram of a processing chamber for forming a component of an electrochemical energy storage device, in accordance with embodiments;
FIG. 3 shows an enlarged section of the processing chamber shown in FIG. 2 ;
4 schematically shows a method for forming a component of an electrochemical energy storage device, according to embodiments.
5 schematically shows a method for forming a component of an electrochemical energy storage device, according to embodiments.

Reference will now be made in detail to various embodiments of the present disclosure, one or more examples of which are illustrated in the drawings. Within the following description of the drawings, like reference numbers refer to like components. Specifically, differences to individual embodiments are described. Each example is provided by way of illustration and is not intended as a limitation of the disclosure. Features illustrated or described as part of one embodiment may be used with or with other embodiments to create a still further embodiment. It is intended that this description cover such modifications and variations.

1 shows an evaporation source 102 for forming a ceramic layer 52 of a component of an electrochemical energy storage device. The evaporation source 102 may be arranged in the processing chamber 100 for example. The processing chamber 100 may be part of a processing system, such as a processing system for a vacuum processing system.

[0021] In the context of the present disclosure, an “electrochemical energy storage device” may be understood as an electrochemical energy storage that may or may not be rechargeable. In this regard, the present disclosure makes no distinction between the term "accumulator" on the one hand and the term "battery" on the other hand. In the context of the present disclosure, the terms “electrochemical energy storage device”, “electrochemical device”, and “electrochemical cell” may be used synonymously hereinafter. For example, the term “electrochemical energy storage device” may also include fuel cells. In the embodiments described herein, an electrochemical cell may be understood to be the basic or minimal functional unit of an energy store. In industrial practice, multiple electrochemical cells can often be connected in series or parallel to increase the total energy capacity of the reservoir. In this context, reference may be made to a number of electrochemical cells. An industrially designed battery may consequently have a single electrochemical cell, or may have multiple electrochemical cells connected in parallel or series.

[0022] In general, an electrochemical energy storage device, for example as a basic functional unit, may comprise two electrodes of opposite polarity, ie a negative anode and a positive cathode. The cathode and the anode may be insulated by a separator arranged between the cathode and the anode to prevent short circuits between the cathode and the anode. The cell may be filled with an electrolyte. The electrolyte may be an ionic conductor which may be in liquid, gel form, or sometimes solid. The separator may be ion permeable and may enable the exchange of ions between the anode and cathode in a charge or discharge cycle. Portions included in the electrochemical energy storage device may be understood as components of the electrochemical energy storage device. Accordingly, some or each of the portions described above including, but not limited to, a cathode, an anode, an electrolyte, and a separator may be considered as a component of an electrochemical energy storage device.

According to embodiments described herein, the evaporation source 102 may include a material source 140 configured to evaporate a material. The material source 140 may be configured to provide at least one element that makes up the ceramic layer 52 . Material source 140 may be configured to evaporate a metal, such as aluminum, for example.

According to embodiments described herein, the evaporation source 102 may include a gas supply 107 configured to supply a process gas. The process gas may be a reactive gas. Specifically, the process gas may be a reactive gas that reacts with the metal evaporated by the material source 140 . The gas supply 107 may be configured to provide at least one element constituting the ceramic layer 52 . For example, the process gas may be oxygen, ozone, argon, and combinations thereof, and/or may include oxygen, ozone, argon, and combinations thereof. According to embodiments described herein, ceramic layer 52 may have a chemical composition that includes oxygen.

[0025] When forming the ceramic layer 52 by evaporation, specifically reactive evaporation, the ceramic layer 52 may not be formed with full stoichiometry or with non-stoichiometry. ) can be formed. In the context of this disclosure, a “stoichiometry”, such as the stoichiometry of the ceramic layer 52 , may be understood as a calculation of the relative amounts of reactants and products in chemical reactions. Thus, “non-stoichiometric” or “not fully stoichiometric” may refer to instances where the product does not include all reactants. In the example where aluminum oxide is the material of the coating layer 52 , the full stoichiometric reaction may be 4Al + 3O ₂ = 2Al ₂ O ₃ . If the aluminum oxide is not perfectly stoichiometric or non-stoichiometric, the product of the reaction may be, for example, Al ₂ O _2.5 . Thus, any composition of AlO _x (x≠1.5) can be considered as non-stoichiometric or not fully stoichiometric. In such a non-stoichiometric ceramic layer, specifically during charging and/or discharging of the electrochemical energy storage device, there may be unbound excess atoms that may react with elements of the electrochemical energy storage device. . In the example of Li-ion batteries, such as during charging and/or discharging of a Li-ion battery, unbound excess atoms capable of reacting with Li-ions traverse through the ceramic layer. In the example where aluminum oxide is the material of the ceramic layer 52 , the unbound excess atoms may be Al.

According to embodiments described herein, the evaporation source 102 may include a plasma source 108 configured to at least partially ionize and/or dissociate the process gas. Specifically, the plasma source 108 may be configured to create a plasma between the material source 140 and the outlet of the evaporation source 102 , among others. That is, the plasma source 108 may be configured to create a plasma between the flexible substrate 111 to be coated and the material source 140 . When practicing embodiments, the stoichiometry of the ceramic layer 52 may be improved. According to advantageous embodiments, a fully stoichiometric ceramic layer 52 may actually be obtained.

[0027] According to embodiments described herein, the plasma may ionize at least 0.01% and/or at most 1% of the process gas. Additionally or alternatively, the plasma dissociates the process gas. In the context of the present application, “ionization” or “ionizing”, such as plasma ionizing a process gas, means, for example, an atom or molecule of the process gas gains or loses electrons to gain a negative or positive charge to form ions. It can be understood as a process that In the example where oxygen is a process gas, ionization of oxygen can form oxygen ions (eg, O ² - , O ^- , O ²⁺ , O ⁺ ) from oxygen molecules (O ₂ ). In the context of this application, “dissociation” or “dissociation”, such as plasma dissociating a process gas, may be understood as a process in which, for example, molecules of the process gas are separated or divided into smaller particles such as atoms. In the example where oxygen is the process gas, ionization of oxygen can form atomic oxygen (O) from oxygen molecules (O ₂ ).

While not intending to be bound by theory, the at least partially ionized process gas may have a higher reactivity towards material evaporated by the material source 140 . Accordingly, the chemical reaction for forming the ceramic layer 52 can be improved in terms of stoichiometry. Additionally, the deposition rate of the evaporation source 102 may actually be increased.

[0029] In the example of aluminum oxide as the material of the ceramic layer 52, aluminum oxide can be formed with improved stoichiometry, particularly full stoichiometry, thereby reducing the amount of unbound excess Al atoms, and/or the aluminum oxide comprises an increased amount of Al ₂ O ₃ . According to embodiments described herein, at least partially ionized oxygen enables the formation of aluminum oxide with improved stoichiometry. Thus, fewer elements of the electrochemical energy storage device, such as the Li-ions described above, can react with the ceramic layer 52 . When practicing embodiments, higher discharge and/or recharge rates, higher voltage, and/or improved lifetime may be obtained. Thus, improved charge transport, increased voltage, and/or extended cycle life may actually be obtained.

Additionally or alternatively, the plasma may at least partially ionize and/or dissociate material evaporated by the evaporation source 102 . In examples where aluminum is the material to be evaporated, ionization of aluminum may form aluminum ions (eg, Al ⁺ , Al ²⁺ , Al ³⁺ ) from atomic aluminum (Al).

Additionally, the mechanical robustness of the ceramic layer 52 may be improved. When practicing the embodiments, the components of the electrochemical energy storage device, and thus the manufacturing, post-processing, and storage of the electrochemical energy storage device can be improved. In particular, the improved rigidity of the ceramic layer 52 may enable winding and/or rewinding of the ceramic layer 52 formed on the flexible substrate 111 .

Accordingly, the ceramic layer 52 may be formed by at least the evaporated material and at least partially ionized process gas. In particular, the evaporation source 102 may be configured to deposit the ceramic layer 52 over the flexible substrate 111 or on the flexible substrate 111 . Specifically, the flexible substrate may have a first side and/or a second side opposite the first side. The ceramic layer 52 may be deposited over or on at least one of the first side and the second side of the flexible substrate 111 . According to embodiments described herein, the at least partially ionized process gas enables the formation of the ceramic layer 52 with improved stoichiometry.

In the context of this disclosure, a “ceramic layer”, such as ceramic layer 52 , may be understood as a layer comprising or formed by a ceramic material. A “ceramic material” may be understood as an inorganic, non-metallic, solid material comprising metal, non-metal, or metalloid atoms, held primarily by ionic and covalent bonds. In the context of the present disclosure, a ceramic material may be understood as a dielectric material which in particular comprises, inter alia, metal and oxygen atoms, such as, for example, aluminum oxide, aluminum nitride and the like. According to embodiments described herein, ceramic layer 52 may be an aluminum oxide layer.

[0034] According to embodiments described herein, a ceramic material is made of metals, i.e., aluminum, silicon, lead, zirconium, titanium, hafnium, lanthanum, magnesium, zinc, tin, cerium, yttrium, calcium, barium, at least one electrically non-conductive or very low conductivity oxide of strontium, and combinations thereof. Although silicon is often referred to as a metalloid, in the context of this disclosure, silicon will be included whenever a metal is referenced. According to embodiments described herein, a component of an electrochemical energy storage device can be optimized for electrochemical cells involving strong alkaline electrolytes, particularly by selecting input materials that are alkali-resistant. For example, zirconium or titanium may be used instead of aluminum or silicon as an inorganic component to form the ceramic layer 52 . In such a case, the ceramic layer 52 may include zirconium oxide or titanium oxide instead of aluminum oxide or silicon oxide.

According to embodiments described herein, ceramic layer 52 may be a porous layer or may have a porosity. In particular, the ceramic layer 52 may be porous to allow certain elements to pass through the ceramic layer 52 .

The flexible substrate 111 may include, among other things, flexible substrates, such as a plastic film, a web, a foil, a flexible glass, or a strip. The term flexible substrate may also include other types of flexible substrates. A flexible substrate as used with the embodiments described herein is flexible. The terms “flexible substrate” or “substrate” may be used synonymously with the term “foil” or the term “web”. In particular, the embodiments described herein may be utilized to coat any kind of flexible substrate, eg, to produce flat coatings having a uniform thickness, or a flexible substrate, or It can be utilized to produce coating patterns or coating structures in a predetermined shape on top of the underlying coating structure. In addition to the ceramic layer, electronic devices and structures may be formed on the flexible substrate by masking, etching, and/or deposition.

[0037] According to embodiments described herein, the flexible substrate 111 may include polyacrylonitrile, polyester, polyamide, polyimide, polyolefin, polytetrafluoroethylene, carboxymethyl cellulose, polyacrylic acid, Polyethylene, polyethylene terephthalate, polyphenyl ether, polyvinyl chloride, polyvinylidene chloride, polyvinylidene fluoride, poly(vinylidenefluoride-co-hexafluoropropylene), polylactic acid, polypropylene, polybutylene, Polybutylene terephthalate, polycarbonate, polytetrafluoroethylene, polystyrene, acrylonitrile butadiene styrene, poly(methyl methacrylate), polyoxymethylene, polysulfone, styrene-acrylonitrile, styrene-butadiene rubber, ethylene and a polymeric material selected from the group of vinyl acetate, styrene maleic anhydride, and combinations thereof. Any other polymeric materials that are stable in the strong reducing conditions found in, for example, lithium based electrochemical energy storage devices may also be used. According to the embodiments described herein, the flexible substrate 111 and/or the ceramic layer 52 are electrochemical energy storage devices involving strong alkaline electrolytes, particularly by selecting input materials that are alkali-resistant. can be optimized for For example, the flexible substrate 111 may include polyolefin or polyacrylonitrile instead of polyester.

For separators, flexible substrate 111 may be made of microporous polyethylene, polypropylene, polyolefin, and/or laminates thereof, and/or microporous polyethylene, polypropylene, polyolefin, and/or laminates thereof.

In the case of the cathode, the flexible substrate 111 may be made of and/or may include aluminum. In this case, the cathode layer may be formed on the flexible substrate 111 . A ceramic layer 52 may be formed on the cathode layer. For example, in the case of a cathode, the flexible substrate 111 may have a thickness of 5 to 12 μm, and/or the cathode layer may have a thickness of up to 100 μm. Additionally or alternatively, the flexible substrate 111 may be a polymer material as described herein, such as polyester, on which a layer of aluminum is deposited, or a polymer material as described herein. , such as polyester. The polymer substrate may be thinner than, for example, an aluminum substrate and/or a deposited layer of aluminum. The deposited layer of aluminum may have a thickness of from about 0.5 μm to about 1 μm. When practicing the embodiments, the thickness of the cathode may be reduced.

In the case of the anode, the flexible substrate 111 may be made of and/or may include copper. In this case, the anode layer may be formed on the flexible substrate 111 . A ceramic layer 52 may be formed on the anode layer. For example, in the case of an anode, the flexible substrate 111 may have a thickness of 5 to 12 μm, and/or the anode layer may have a thickness of up to 100 μm. Additionally or alternatively, the flexible substrate 111 may be a polymeric material as described herein, such as polyester, on which a layer of copper is deposited, or a polymeric material as described herein. , such as polyester. The polymer substrate may be thinner than, for example, a copper substrate and/or a deposited layer of copper. The deposited layer of copper may have a thickness of from about 0.5 μm to about 1 μm. When practicing the embodiments, the thickness of the anode may be reduced.

According to embodiments described herein, the material of the flexible substrate 111 , specifically a polymer material, may have a high melting point, such as 200° C. or higher. Components of electrochemical energy storage devices comprising polymeric materials having a high melting point may be useful in electrochemical energy storage devices having a fast charge cycle. Indeed, in particular, due to the high thermal stability of a component comprising a polymer material having a high melting point according to the embodiments described herein, an electrochemical energy storage device equipped with such a component may not be very thermally sensitive and , and it may be possible to withstand temperature increases due to rapid charging without damage to the electrochemical energy storage device or adverse changes to the components. When practicing embodiments, a faster charging cycle may be achieved, which may be useful for electric vehicles that may be charged within a shorter period of time.

According to embodiments described herein, the flexible substrate 111 having the ceramic layer 52 specifically has a porosity in the range of 10% to 90%, specifically in the range of 40% to 80%. can have The flexible substrate 111 and/or the ceramic layer 52 may actually provide a path for the electrolyte and reduce electrolyte penetration time. In the context of the present disclosure, “porosity”, such as the porosity of ceramic layer 52 and/or flexible substrate 111 , may relate to the accessibility of open pores. For example, the porosity may be determined through common methods, such as, for example, by mercury porosimetry, and/or calculated from the density and volume of the materials used, assuming that all pores are open pores.

According to embodiments described herein, the electrochemical energy storage device may be a Li-ion battery. In Li-ion batteries, the flexible substrate 111 can usually be made of microporous polyethylene and polyolefin. During the electrochemical reactions of charge and discharge cycles, Li-ions are transported through pores in the ceramic layer 52 and/or the flexible substrate 111 between the two electrodes of the Li-ion battery. High porosity can increase ionic conductivity. However, some flexible substrates 111 with high porosity may be prone to short circuits electrically, for example, when Li-dendrites formed during cycling create shorts between the electrodes.

[0044] The present disclosure can provide very thin components of an electrochemical energy storage device, such as very thin separators. When practicing embodiments, the proportion of components of the electrochemical energy storage device that do not contribute to the activity of the electrochemical energy storage device may be reduced. Additionally, a reduction in thickness can simultaneously increase ionic conductivity. Components according to embodiments described herein may enable increased density, such as in a battery stack, and thus, a large amount of energy may be stored in the same volume. When practicing the embodiments, through enlargement of the electrode area, the limiting current density can likewise be increased.

[0045] Embodiments described herein may be used for the creation of separators. The separators may be separate from the electrochemical energy storage device, or may be integrated directly into the electrochemical energy storage device, such as, for example, lithium-ion batteries with integrated separators. In integrated separator applications, a single-layer separator or a multi-layer separator can be formed directly above the electrode of the electrochemical energy storage device. Additionally, ceramic layer 52 may be coated on an electrode, such as an anode or cathode, of an electrochemical energy storage device. Accordingly, the components of the electrochemical energy storage device may be a separator or separator membrane, an electrolyte, an anode, and/or a cathode.

According to embodiments described herein, the ceramic layer 52 may be formed by evaporating a material, specifically a metal. Specifically, the ceramic layer 52 may be formed by evaporating the metal, for example, in an inductively heated crucible. Additionally, a process gas, such as oxygen, may be supplied to form the ceramic layer 52 . According to embodiments described herein, ceramic layer 52 may be formed by reactive evaporation. According to embodiments described herein, ceramic layer 52 may have a chemical composition that includes oxygen. When practicing the embodiments, very high coating rates can be achieved when compared to common separator coating techniques such as dip-coating. Specifically, the coating rates may be changed depending on the type and thickness of the ceramic material to be formed on the flexible substrate 111 .

According to embodiments described herein, the thickness of the ceramic layer 52 formed on the flexible substrate 111 is 25 nm or more, specifically 50 nm or more, particularly 100 nm or more, and/or It may be 1000 nm or less, specifically 500 nm or less, in particular 150 nm or less. When practicing the embodiments, very high energy densities can be achieved in electrochemical energy storage devices.

The flexible substrate 111 may be moved, such as past the evaporation source 102 , while being processed in the processing chamber 100 . According to embodiments described herein, a substrate transport mechanism may be provided. For example, the flexible substrate 111 may be transported past the evaporation source 102 along the transport path P.

As shown in FIG. 1 , a first substrate support 22 , and/or a second substrate support 24 arranged at a distance from the first substrate support 22 may be provided. The first substrate support 22 and/or the second substrate support 24 may also be referred to as rollers, eg, a first roller and/or a second roller. The first roll 22 and the second roll 24 may be part of a substrate transport mechanism. According to embodiments described herein, flexible substrate 111 may be transported from first roll 22 to second roll 24 . The flexible substrate 111 is transported from the first roll 22 to the second roll 24 (represented by a circle with a point in the center to indicate that the transport path P is perpendicular to the projection plane). may be transported and/or transported according to P). According to embodiments described herein, the substrate transport mechanism may be configured to transport the flexible substrate 111 from the first roll 22 to the second roll 24 along the transport path P. The evaporation source 102 may be provided in a position between the first roll 22 and the second roll 24 . According to the embodiments described herein, the evaporation source 102 may be arranged along the transport path P. According to embodiments described herein, the ceramic layer 52 may be formed while the flexible substrate 111 is being transported from the first roll 22 to the second roll 24 . According to embodiments described herein, the ceramic layer 52 may be subjected to an oxidizing atmosphere while the flexible substrate 111 is transported from the first roll 22 to the second roll 24 .

In some implementations, the flexible substrate 111 can be unwound from a storage roller, transported onto an outer surface of the coating drum, and guided along the outer surfaces of additional rollers. The coated flexible substrate may be wound on a wind-up spool.

[0051] In the context of the present disclosure, for example, a “roll”, “roller”, or “roller device” as part of a roller assembly is a substrate (or part of a substrate), such as a flexible substrate 111 (or flexible substrate). A portion of the substrate 111 ) may be understood as a device that provides a surface that can be contacted while the substrate is in a deposition arrangement (such as a deposition apparatus or evaporation chamber). At least a portion of the roller device may include a circular shape for contacting the substrate. In some embodiments, the roller device may have a substantially cylindrical shape. The substantially cylindrical shape may be formed about a straight longitudinal axis, or it may be formed about a curved longitudinal axis. According to some embodiments, a roller device as described herein may be adapted to contact a flexible substrate. A roller device as referred to herein is a guiding roller adapted to guide a substrate while the substrate is being coated (or while a part of the substrate is being coated) or while the substrate is in a processing apparatus, defined in the substrate to be coated. It may be a spreader roller adapted to provide tension, a deflection roller for deflecting the substrate along a defined travel path, or the like.

According to embodiments described herein, the processing chamber may be configured to process a flexible substrate 111 having a length of 500 m or more, 1000 m or more, or several kilometers. The substrate width may be 100 mm or more, 300 mm or more, 500 mm or more, or 1 m or more. The substrate width may be less than or equal to 5 m, in particular less than or equal to 2 m. Typically, the substrate thickness may be at least 5 μm and up to 200 μm, in particular between 15 μm and 20 μm.

FIG. 2 shows a schematic diagram of a processing chamber 100 for depositing a ceramic layer 52 on a surface of a flexible substrate 111 . The processing chamber 100 may include a loading/unloading chamber 101 . The loading/unloading chamber 101 may be configured to load/unload the flexible substrate 111 into and/or from the processing chamber 100 . According to embodiments described herein, the loading/unloading chamber may be maintained under vacuum during processing of the flexible substrate 111 . A vacuum device 190 , such as a vacuum pump, may be provided to evacuate the loading/unloading chamber 101 .

According to embodiments described herein, the loading/unloading chamber 101 may include an unwinding module 110 and/or a rewinding module 130 . The unwinding module 110 may include an unwind roll for unwinding the flexible substrate 111 . During processing, flexible substrate 111 may be unwound (as indicated by arrow 113 ) and/or guided to coating drum 120 by one or more guide rolls 112 . After being processed, the flexible substrate 111 may be wound onto a rewind roll in the rewinding module 130 (arrow 114 ).

Additionally, the loading/unloading chamber 101 may include a tensioning module 180 including, for example, one or more tensioning rollers. Additionally or alternatively, the loading/unloading chamber 101 may also include a pivot device 170 , such as, for example, a pivot arm. The pivot device 170 may be configured to be movable with respect to the rewinding module 130 .

According to embodiments described herein, the unwinding module 110 , the rewinding module 130 , the guide roll 112 , the pivot device 170 , the tensioning module 180 may be configured to include a roller assembly and/or It may be part of a substrate transport mechanism.

According to embodiments described herein, the processing chamber 100 may include an evaporation chamber 103 . The evaporation source 102 may be similar or identical to the evaporation source 102 described in particular with reference to FIG. 1 . The evaporation chamber 103 may include an evaporation source 102 . The evaporation chamber 103 may be evacuated by a vacuum device 190 which may also be used to evacuate the loading/unloading chamber 101 . Additionally or alternatively, the evaporation chamber 103 may have a vacuum device separate from the vacuum device 190 that may also be used to evacuate the loading/unloading chamber 101 .

As illustratively shown in FIG. 2 , the evaporation source 102 may include a material source 140 . The material source 140 may be configured to evaporate a material, specifically a metal. According to embodiments described herein, material source 140 may include one or more evaporation boats. Material source 140 may further include one or more wires to be fed into material source 140 . Specifically, there may be one wire for each evaporation boat. The one or more wires may include and/or be made of the material to be evaporated. Specifically, one or more wires may supply material to be evaporated.

According to embodiments described herein, the material source 140 may be one or more inductively heated crucibles. Induction heating crucibles may be configured to evaporate metals in a vacuum environment, for example by RF induction-heating, in particular MF induction-heating. Additionally, the metal may be provided in interchangeable crucibles, such as, for example, one or more graphite vessels. The exchangeable crucible may include an insulating material surrounding the crucible. One or more induction coils may be wrapped around the crucible and insulating material. According to embodiments described herein, the one or more inductive coils may be water cooled. If interchangeable crucibles are used, there is no need to feed a wire into the material source 140 . Interchangeable crucibles can be pre-loaded with metal and can be replaced or refilled periodically. Specifically, providing the metal in batches has the advantage of precisely controlling the amount of metal that is evaporated.

[0060] Unlike common evaporation methods that use resistance heating of crucibles to vaporize metals, using an inductively heated crucible allows the heating process to occur inside the crucible instead of through heat conduction by an external source. make it possible Induction heating crucibles have the advantage that all the walls of the crucible are heated very quickly and uniformly. The evaporation temperature of the metal can be more tightly controlled than with conventional resistance heating crucibles. When using an inductively heated crucible, it may not be necessary to heat the crucible above the evaporation temperature of the metal. When practicing embodiments, a more controlled and efficient evaporation of the metal may be provided to make the ceramic layer formed on the flexible substrate more homogeneous. Close control of the temperature of the crucible can also prevent/reduce pinholes and through-hole defects in the ceramic layer by reducing the likelihood of splashing of evaporating metal. Pinhole and through-hole defects in separators can cause shorts in electrochemical cells.

According to embodiments described herein, an inductively heated crucible may be surrounded, for example, by one or more induction coils (not shown in the figures). The induction coils may be an integral part of an inductively heated crucible. Additionally, the induction coils and the induction heated crucible may be provided as separate parts. Providing the induction heating crucible and induction coils separately may enable easy maintenance of the evaporation apparatus.

According to embodiments described herein, the evaporation source may include one or more electrode beam sources. The one or more electrode beam sources may provide one or more electrode beams to evaporate the material to be evaporated.

According to embodiments described herein, a power source 240 (see FIG. 3 ) may be provided. The power source 240 may be coupled to the induction coils. The power source may be an AC power source that may be configured to provide electricity at a low voltage but at a high current and high frequency. Additionally, the reactive power can be increased, for example by including a resonant circuit. According to embodiments described herein, in addition to or alternatively to electrically conductive materials, an inductively heated crucible may include, for example, ferromagnetic materials. Magnetic materials, for example, can improve the induction heating process and enable better control of the evaporation temperature of the metal.

According to embodiments described herein, the coating drum 120 of the processing chamber 100 may separate the evaporation chamber 103 and the loading/unloading chamber 101 . The coating drum 120 may be configured to guide the flexible substrate 111 into the evaporation chamber 103 . Specifically, the coating drum 120 may be arranged in the processing chamber to allow the flexible substrate 111 to pass over the evaporation source 102 . According to embodiments described herein, the coating drum 120 may be cooled.

The evaporation source 102 may include a plasma source 108 . The plasma source may be configured to at least partially ionize and/or dissociate the process gas. Specifically, the plasma source 108 may be configured to create a plasma between the material source 140 and the coating drum 120 .

The plasma source 108 may be configured to operate at an RF frequency, such as 27.12 MHz. The plasma source 108 may be configured for a pre-pressure greater than or equal to 2.5 bar and/or less than or equal to 5 bar. The plasma source 108 may be configured to provide an ion energy greater than 30 eV and/or less than or equal to 1100 eV. The plasma source 108 may be configured to provide a magnetic field of up to 20 mT per coil. The plasma source 108 may be configured to operate at a pressure greater than or equal to 10 ⁻⁵ bar and/or less than or equal to 10 ⁻² bar.

The plasma source 108 may be, for example, an electron beam device configured to ignite a plasma using an electron beam. According to further embodiments herein, the plasma source may be a hollow anode deposition plasma source. Plasma can help prevent/reduce pinholes and through-hole defects in the porous coating on the substrate by further reducing the likelihood of splashing of evaporating metal. The plasma may also further excite particles of vaporized metal. According to embodiments described herein, plasma can increase the density and uniformity of a porous coating deposited on a flexible substrate.

According to embodiments described herein, the evaporation source 102 may include a gas supply for supplying a process gas. The gas supply may include a gas introduction device 107 . The gas introduction device 107 may be arranged to controllably introduce a process gas into the evaporation source 102 and/or the evaporation chamber 103 . The gas introduction device may include, for example, a supply tube and a nozzle connected to a process gas supply for providing process gas into the evaporation source 102 and/or the evaporation chamber 103 .

[0069] The process gas may be a reactive gas. Specifically, the process gas may be a reactive gas that reacts with the metal evaporated by the material source 140 . For example, the process gas may be oxygen, ozone, argon, and combinations thereof, and/or may include oxygen, ozone, argon, and combinations thereof.

When oxygen is included in the process gas, the oxygen gas may react with the evaporated metal, for example, to form the ceramic layer 52 on the flexible substrate 111 . Components of the electrochemical energy storage device, such as a separator or separator membrane, electrolyte, cathode, and anode, may include AlO _x . A metal such as aluminum can be evaporated, for example by means of an induction heating crucible, and oxygen can be supplied to the evaporated metal via a gas introduction device.

According to embodiments described herein, the processing chamber may include an oxidation module 150 . The oxidation module 150 may be an annealing module for annealing the ceramic layer 52 . As exemplarily shown in FIG. 2 , the oxidation module 150 may be arranged downstream of the evaporation chamber 103 . The oxidation module 150 may be configured to subject the ceramic layer 52 to an oxidizing atmosphere and/or an annealing atmosphere. According to embodiments described herein, ceramic layer 52 may be subjected to an annealing atmosphere and/or an oxidizing atmosphere, specifically at an elevated temperature. Additionally, the oxidation module 150 may be configured to subject the ceramic layer to an oxidizing atmosphere and/or an anneal atmosphere over an oxidizing distance and/or annealing distance. The oxidation distance and/or annealing distance may be long enough to obtain the intended amount of oxidation and/or annealing. When practicing embodiments, the stoichiometry of the ceramic layer 52 may be improved. According to advantageous embodiments, a fully stoichiometric ceramic layer 52 may actually be obtained.

[0072] In the context of the present application, an “oxidizing atmosphere”, such as an oxidizing atmosphere in which the ceramic layer 52 may be subjected, is, for example, an atmosphere that enables an oxidation reaction to improve the stoichiometry of the ceramic layer 52 . can be understood According to embodiments described herein, the oxidizing atmosphere may contain greater than 20 vol % oxygen.

According to embodiments described herein, the oxidation module 150 may include a gas assembly. The gas assembly may be configured to supply an oxidizing gas, such as oxygen. According to embodiments described herein, oxidation module 150 may include a heating assembly (not shown). The heating assembly may be configured to raise the temperature of at least one of the supplied oxidizing gas, the flexible substrate 111 , and the ceramic layer 52 .

According to embodiments described herein, the oxidation module 150 may include a suction device. The aspiration device may be configured to draw off excess oxidizing gas, ie, an oxidizing gas not used to oxidize the ceramic layer 52 . The suction device may be arranged opposite the gas assembly with respect to the flexible substrate 111 . Accordingly, the process gas supplied by the gas assembly may be provided to the ceramic layer 52 , traverse the flexible substrate 111 , and sucked in by the suction device. When practicing embodiments, contamination of the processing chamber 100 may be prevented.

Additionally, the oxidation module 150 may include a plasma source. The plasma source of the oxidation module 150 may be configured to create a plasma between the gas assembly and the flexible substrate. The plasma source 150 of the oxidation module 150 may be, for example, an electron beam device configured to ignite a plasma using an electron beam. According to further embodiments herein, the plasma source may be a hollow anode deposition plasma source. Additionally, the plasma source of the oxidation module 150 may be the same as or similar to the plasma source 108 of the evaporation source 102 described herein, particularly with reference to FIGS. 2 and 3 . The plasma may ionize and/or heat the oxidizing gas supplied by the gas assembly. Accordingly, the oxidation rate of the ceramic layer 52 can be increased.

[0076] According to embodiments described herein, the oxidation module 150 may include a heating assembly. The heating assembly may be configured to raise the temperature of at least one of the oxidation chamber, the oxidizing atmosphere, the flexible substrate 111 , and the ceramic layer 52 . Specifically, the heating assembly may be configured to create an elevated temperature. Accordingly, the oxidation rate of the ceramic layer 52 can be increased. When practicing the embodiments, a fully stoichiometric ceramic layer may be obtained.

FIG. 3 shows an enlarged section of the processing chamber 100 shown in FIG. 2 . According to embodiments described herein, the processing chamber 100 may include a control system 220 . The control system 220 can be coupled to at least one of the evaporation source 102 , the oxidation module 150 , the gas introduction device 107 , the plasma source 108 , and the power source 240 . According to the embodiments described herein, the control system 220 is configured to control the power provided to the evaporation source 102 , the power provided to the plasma source 108 , and/or the evaporation source by means of the gas introduction device 107 . may be configured to adjust at least one of an amount of processing gas and/or an orientation of a gas flow of processing gas introduced into 102 . According to embodiments described herein, control system 220 may additionally or alternatively be configured to: an amount of oxidizing gas and/or orientation of a gas flow of oxidizing gas supplied by oxidation module 150, and may be configured to adjust the suction force of the suction device.

According to embodiments described herein, the gas introduction device 107 may be arranged to provide a gas flow of the process gas in a direction approximately parallel to the evaporation direction 230 of the metal. According to embodiments described herein, the orientation of the gas flow provided by the gas introduction device may be adjusted according to at least one of the composition and uniformity of the ceramic layer 52 . When practicing the embodiments, a more efficient reaction between the vaporized metal and the reactive gas to form the ceramic layer can be ensured. Arranging the gas introduction device 107 to introduce the reactive gas in a direction essentially parallel to the evaporation direction 230 of the metal from the material source 140 also determines the amount of process gas that interacts with the evaporated metal. By allowing more precise control, it can help to better control the coating process.

According to embodiments described herein, the plasma 210 may be guided in a direction essentially perpendicular to the evaporation direction 230 of the metal. When practicing embodiments, splashing of evaporating metal may be prevented and/or pinhole defects in the ceramic layer may be reduced.

Although oxidation module 150 is shown arranged in-line with evaporation source 102 in FIGS. 1-3 in FIGS. 1-3, oxidation module 150 is turned off as outlined above. - Can be arranged off-line. For example, an oxidation chamber may be provided in which an oxidation module 150 may be arranged. The oxidation chamber may be separate from the evaporation chamber 103 . Additionally, the oxidation chamber may be separate from the processing chamber 100 . Moreover, the processing chamber 100 may be a multi-chamber system including multiple processing chambers, such as an evaporation chamber 103 and/or an oxidation chamber. Additionally, the processing chamber 100 may include a storage chamber in which a rewound flexible substrate 111 having a ceramic layer 52 deposited on the flexible substrate 111 may be transferred to the oxidation chamber. Before being, the rewound flexible substrate 111 having the ceramic layer 52 deposited thereon may be stored in its storage chamber.

4 shows a flow diagram of a method 500 for forming a ceramic layer of a component of an electrochemical energy storage device. The method may include at least one of operations 510 - 530 . According to operation 510 , a material may be evaporated on or over the flexible substrate 111 . According to operation 520 , a process gas may be supplied. According to operation 530 , the process gas may be at least partially plasma ionized. Ceramic layer 52 may be formed by at least vaporized material and at least partially ionized process gas. When practicing the embodiments, a ceramic layer with improved stoichiometry can be obtained.

5 schematically shows a method 300 for forming a component of an electrochemical energy storage device. According to embodiments described herein, method 300 may include providing 310 a flexible substrate having a front side and a back side. According to embodiments described herein, providing the flexible substrate may include guiding the flexible substrate from the unwinding module through the coating drum of the evaporation apparatus to the rewinding module.

[0083] According to embodiments described herein, the method may further comprise evaporating 320 the material, specifically in an induction heating crucible. Specifically, according to embodiments described herein, aluminum and/or silicon may be evaporated by an inductively heated crucible. In embodiments herein, the method further comprises applying 330 a ceramic layer to at least one of the front and back surfaces of the flexible substrate.

[0084] According to embodiments described herein, a process gas may be supplied. The vaporized metal may react with the at least partially ionized process gas to form a ceramic layer on the flexible substrate. Metals can evaporate in a vacuum environment. For example, evaporated aluminum can react with oxygen to form a porous AlO _x layer on the flexible substrate.

[0085] According to embodiments described herein, evaporating metal in an induction heating crucible comprises sensing 340 an evaporation temperature at which the metal is evaporated, and in accordance with the sensed evaporation temperature, an induction heating crucible It may further include adjusting the power provided to vaporize the metal in the Monitoring and adjusting the evaporation temperature can improve the energy efficiency of a method for forming a component of an electrochemical energy storage device, and/or help prevent any pinhole defects in the porous coating applied to the flexible substrate. can

In embodiments described herein, the ceramic layer applied to the flexible substrate may have a thickness of approximately 25 nm to approximately 300 nm, such as, for example, 100 nm to 200 nm.

[0087] According to embodiments described herein, evaporating the metal in the induction heating crucible may further include providing 350 a process gas, such as oxygen, to the evaporated metal. The reactive gas may be provided in a direction essentially parallel to the direction of evaporation of the metal.

[0088] The method for forming a component of an electrochemical energy storage device can further include providing 360 a plasma between the evaporated metal and the flexible substrate. Plasma may increase the stoichiometry and/or density of the porous coating on the flexible substrate, and may also help reduce pinhole defects in the porous coating. When practicing the embodiments, the stoichiometry of the ceramic layer may be improved. Even fully stoichiometric ceramic layers can be obtained in practice. Specifically, according to embodiments described herein, the plasma may be provided by, for example, an electron beam device or a hollow anode deposition plasma source. The density of the porous coating can be affected by the density of the plasma.

[0089] The stoichiometry of the deposited porous layer on the flexible substrate may be influenced by, for example, the evaporation rate of the metal, the amount of process gas provided to the evaporated material, and/or plasma ionization of the process gas. An additional aspect that may affect the stoichiometry of the deposited porous layer may be the pressure difference between the vacuum inside the evaporation chamber and the pressure of the ambient atmosphere.

[0090] According to embodiments described herein, a method for forming a component of an electrochemical energy storage device may include subjecting a ceramic layer 52 to an oxidizing atmosphere at an elevated temperature (370). have.

[0091] This written description is intended to disclose the present disclosure, including the best mode, and also to make and use any apparatus or system, and to perform any included methods. Use examples to make the content actionable. Although various specific embodiments have been disclosed above, mutual features of the embodiments described above may be combined with each other. The patentable scope is defined by the claims, and other examples are where examples have structural elements that do not differ from the wording of the claims, or where examples include equivalent structural elements with insubstantial differences from the wording of the claims. , are intended to be within the scope of the claims.

Claims (15)

A method for forming a ceramic layer (52) of a component of an electrochemical energy storage device, comprising:
evaporating the material onto the flexible substrate (111);
supplying a process gas; and
at least partially plasma ionizing the process gas;
includes,
the ceramic layer 52 is formed by at least the evaporated material and the at least partially ionized process gas;
wherein the plasma ionizes at least one of at least 0.01% and at most 1% of the process gas;
A method for forming a ceramic layer of a component of an electrochemical energy storage device. The method of claim 1,
wherein the process gas comprises oxygen;
A method for forming a ceramic layer of a component of an electrochemical energy storage device. 3. The method according to claim 1 or 2,
wherein the ceramic layer 52 has a chemical composition comprising oxygen;
A method for forming a ceramic layer of a component of an electrochemical energy storage device. 3. The method according to claim 1 or 2,
wherein the at least partially ionized process gas enables formation of the ceramic layer (52) with improved stoichiometry;
A method for forming a ceramic layer of a component of an electrochemical energy storage device. 3. The method according to claim 1 or 2,
wherein the ceramic layer 52 is an aluminum oxide layer,
A method for forming a ceramic layer of a component of an electrochemical energy storage device. 3. The method according to claim 1 or 2,
The electrochemical energy storage device is a lithium battery,
A method for forming a ceramic layer of a component of an electrochemical energy storage device. 3. The method according to claim 1 or 2,
The component is a separator film,
A method for forming a ceramic layer of a component of an electrochemical energy storage device. 3. The method according to claim 1 or 2,
wherein the component is an electrode,
A method for forming a ceramic layer of a component of an electrochemical energy storage device. 3. The method according to claim 1 or 2,
transporting the flexible substrate (111) from a first roll (22) to a second roll (24);
the ceramic layer (52) is formed while the flexible substrate (111) is being transported from the first roll to the second roll;
A method for forming a ceramic layer of a component of an electrochemical energy storage device. An evaporation source (102) for forming a ceramic layer of a component of an electrochemical energy storage device, comprising:
a material source 140 configured to evaporate the material;
a gas supply unit 107 configured to supply a process gas; and
A plasma source 108 configured to at least partially ionize the process gas.
includes,
the ceramic layer 52 is formed by at least the evaporated material and the at least partially ionized process gas;
wherein the plasma of the plasma source (108) ionizes at least one of at least 0.01% and at most 1% of the process gas;
An evaporation source for forming a ceramic layer of a component of an electrochemical energy storage device. 11. The method of claim 10,
wherein the plasma source (108) is a plasma beam source;
An evaporation source for forming a ceramic layer of a component of an electrochemical energy storage device. A process chamber (100) comprising:
an evaporation source (102) according to claim 10 or 11; and
A substrate transport mechanism configured to transport a flexible substrate 111 through the process chamber 100 .
includes,
wherein the evaporation source (102) is arranged relative to the substrate transport mechanism such that the ceramic layer (52) is formed on the flexible substrate (111).
process chamber. 13. The method of claim 12,
The substrate transport mechanism comprises a first roll 22 and a second roll 24, and along a transport path P, the flexible substrate ( 111), wherein the evaporation source (102) is arranged along the transport path (P),
process chamber. 14. The method of claim 13,
The process chamber 100 is a vacuum process chamber,
process chamber. delete

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