PRE-LOADED PROTECTIVE ANODE, BATTERY AND METHOD OF MANUFACTURING

Abstract

The present disclosure relates to a method for manufacturing an electrode (1n) comprising a current collecting element (10), a coating of solid or semi-solid electrolyte (20) and a corresponding electrode component, the method comprising depositing (300) a quantity of an anode metal composition as a layer between the current collecting element and a solid electrolyte coating the current collecting element by an electroplating process involving directional migration of anode metal ions through the electrolyte coat, the solid electrolyte comprising i) a first layer coating the current collecting element, at least initially containing one or more additives that react with the plated anode metal composition to form a solid electrolyte interfacial layer, and ii) a second layer coating the first layer, which is resistant to inward penetration of solvents contained in the plating electrolyte (302). The present disclosure further relates to a battery comprising the electrode component.

Description

[Technical field]

[0001] The present disclosure relates to an electrode component. In particular, the present disclosure relates to an electrode component comprising a current collecting element and a coating of a solid electrolyte, and such an electrode component preloaded with a quantity of an anode metal composition. The present disclosure relates to a battery, such as a lithium-based battery, comprising the electrode component with the preloaded anode metal composition, and a method for manufacturing the electrode component and the battery. [Background technology]

[0002] Rechargeable lithium-ion batteries (LiBs) are today's technology of choice in electric vehicles and renewable energy storage grids. To improve energy density, next generation battery technology is trending towards lithium metal anodes with high specific capacity, potentially up to 3860 mAh / g, and low redox potential of -3.04 V. These anodes can be paired with cathodes from a variety of chemistry options, such as NMC (lithium nickel manganese cobalt oxide), LFP (lithium iron phosphate), LNMO (lithium nickel manganese oxide), sulfur, or air.

[0003] During charging, Li ions migrate from the cathode through the electrolyte to the anode and become Li metal (Li 0 During discharge, they are returned to the cathode. However, during plating / demolding cycles, the battery suffers from lithium loss due to adverse reactions of lithium with the electrolyte and / or due to the formation of porous or dendritic lithium deposits, which further present an increasing risk of short circuits and reduce the life and performance of the operable battery.

[0004] X. Zhang et al. (Acc. Chem. Res., 52, 3223-3232, 2019) describe a dendrite suppression strategy that may reduce Li loss during battery operation. However, Li loss, especially during the first plating cycle, remains disproportionately high.

[0005] Compensation for the lost lithium is not obvious, since lithium (like other alkali metals) is highly reactive to the surrounding environment, which may result in the formation of unfavorable resistive oxide and / or nitride surface layers that adversely affect the cycling of the battery, the deposition of lithium thereon, and thus the battery life. To mitigate the growth of the oxide surface layer, the lithium may be treated in an Ar atmosphere. In practice, however, this does not satisfactorily reduce the growth rate and also significantly increases the operating costs.

[0006] WO2018190559A1 discloses the electroplating of Li onto a current collector from a plating solution containing lithium nitrate and a metal nitrate.

[0007] CN112670450A discloses electroplated lithium followed by N2 gas exposure and coating with a polymer / solid electrolyte to reduce surface oxidation.

[0008] However, a need remains for a solution that provides a way to provide lithium metal while mitigating the formation of an oxide surface layer. [Prior art documents] [Patent documents]

[0009] [Patent Document 1] International Publication No. 2018190559 [Patent Document 2] China Patent Application Publication No. 112670450 [Non-patent literature]

[0010] [Non-Patent Document 1] X. Zhang et al. (Acc. Chem. Res., 52, 3223-3232, 2019) [Non-Patent Document 2] J. Mol. Model. 23, Paper: 6, (2017) [Non-Patent Document 3] H. Wu et al. (Recent Progress in Understanding Solid Electrolyte Interphase on Lithium Metal Anodes, Advanced Energy Materials, Vol. 11, No. 5, 2021, 2003092) Summary of the Invention [Problem to be solved by the invention]

[0011] The present disclosure aims to overcome known limitations by simultaneously providing an electrode component that includes a pre-loaded amount of an anode metal, e.g., lithium, coated with an electrolyte, typically a solid electrolyte layer, that insulates the lithium from the surrounding environment. [Means for solving the problem]

[0012] The present disclosure provides an effective, production-compatible surface protection for reactive anode metals, such as Li.

[0013] At the same time, the disclosed solution improves subsequent anode metal plating and reduces porous / dendritic anode metal deposition, improving battery life and reducing the risk of short circuits.

[0014] In particular, aspects of the present disclosure relate to methods of manufacturing an electrode assembly that includes a current collecting element and a solid or semi-solid layer, coat, or electrolyte provided along a surface of the current collecting element.

[0015] The method disclosed herein advantageously provides an electrode component with a preloaded amount of anode metal composition. In particular, the method mitigates the decomposition of the input anode metal, such as lithium metal, due to contact with the surrounding environment. The electrode component can be used to serve as an anode component in battery applications, such as rechargeable lithium metal batteries, whereby the electrolyte layer, due to its solid or semi-solid nature, can be advantageously used as an ion-conducting separator between the electrode component and the counter electrode. As detailed herein below, the present disclosure further provides one or more improved battery performances in terms of energy density, safety, and / or lifespan.

[0016] The method of manufacturing the electrode component includes plating a quantity of an anode metal composition, typically comprising one or more alkali metals, such as lithium, sodium or potassium, as a layer between a current collecting element and an electrolyte coating the current collecting element by an electroplating process. The electroplating process involves the directional migration of anode metal ions from an anode metal source, such as a plating electrolyte, through the electrolyte coating towards the current collecting element, where the solid or at least semi-solid electrolyte layer includes one or more additives that form a solid electrolyte interface (SEI), at least prior to plating. The SEI is formed as a layer along the interface between the current collecting element and the electrolyte by reaction with the plated anode metal. The SEI layer protects the formed anode metal, which is typically highly reactive, by inhibiting the permeation of reactive species such as O2, N2 and / or CO2 from the surrounding environment (e.g., within a production environment such as a drying room), while allowing the transport of anode metal ions towards the current collecting element for further plating. Protection from decomposition of the underlying anode metal composition advantageously mitigates decomposition of the anode metal and the formation of materials (e.g., oxides and / or nitrides). Mitigating anode metal decomposition may advantageously improve the amount of available battery active material in the context of a battery, e.g., improving energy density. Mitigating anode metal decomposition may further improve the performance and / or safety of the electrode and / or battery, e.g., with respect to improved plating uniformity during operation of the electrode or cycling of the battery.

[0017] The solid or semi-solid electrolyte is also advantageously resistant to inward penetration of solvents contained in the plating electrolyte, which avoids or at least reduces inward penetration of solvents contained in the plating electrolyte, thereby reducing decomposition / reaction with the plated anode metal by the solvent.

[0018] Typically, the electrolyte layer is formed as a stack of at least two different layers, including a first layer that at least initially contains one or more functional additives that cover and typically directly contact the current collecting element and form an SEI layer. After plating, for example in the final electrode part, the amount of additives is optionally significantly reduced to zero or essentially zero. A second layer that is resistant to the inward penetration of the solvent contained in the plating electrolyte covers the first layer. By providing separate layers, the SEI formation is advantageously separated from the resistance to the inward penetration of the solvent contained in the plating electrolyte.

[0019] In a preferred embodiment, the current collecting element is formed as a flexible foil, such as a metal foil or a metal-coated flexible carrier. The formed electrode part may therefore advantageously be flexible. The manufacturing method may advantageously be configured as a roll-to-roll process. Thus, in a preferred embodiment, the method comprises conveying the foil through a station configured to apply an electroplating process. Roll-to-roll manufacturing may advantageously enable the manufacture of electrode parts in bulk using a cost-efficient continuous process that produces rolls of pre-loaded electrodes.

[0020] In another or further preferred embodiment, the method includes controlling, e.g., by a controller, the amount of anode metal electroplated (e.g., the thickness of the anode metal layer) according to a predetermined target by one or more of controlling plating parameters including the magnitude, duration and / or pulse shape of the electroplating current during electroplating and / or by controlling the contact time of the substrate with the plating electrolyte (e.g., residence time in the plating bath).

[0021] The present disclosure further relates to an electrode component comprising a current collecting element and an electrolyte layer provided along a face of the current collecting element, It will be understood that the component may be manufactured by a method according to the present disclosure.

[0022] For example, the electrode components produced by the disclosed methods advantageously include a preloaded amount of anode metal composition. The anode metal composition is provided as a layer between the current collecting element and the electrolyte coat. The solid electrolyte interface formed as a layer along the interface between the electrolyte and the layer of anode metal composition mitigates anode metal degradation due to reaction of the anode metal with the surrounding environment. The current collecting element and the formed electrode components can advantageously be flexible. Because the anode metal is protected, the electrode components can advantageously be stored as rolls, sheets, or pieces cut to size for further use, for example, in a battery.

[0023] In some embodiments, an electrode part is provided, preferably obtainable by the method disclosed herein, the electrode part being a current collecting element provided thereon with an electrolyte coating, the electrolyte coating comprising: i) a first layer coating the current collecting element, optionally containing one or more functional additives that react to form a solid electrolyte interface layer after reaction with a plated anode metal composition provided by electroplating; and ii) a second layer coating the first layer; a preloaded amount of anode metal composition provided as a layer between the current collecting element and the electrolyte coating; and a solid electrolyte interface formed as a layer along the interface between the coat of electrolyte and the layer of anode metal composition, whereby the second layer is relatively more resistant to plating solvents, e.g., to ingress of solvent ingress from the plating solution, than the first layer.

[0024] Without wishing to be bound by theory, the inventors have found that more resistant to plating solvents (e.g., plating solvent penetration) is understood to include compositions that are relatively non-polar than the first layer. Alternatively, or in addition, more resistant to solvent penetration may be understood as having a relatively low affinity (mutual solubility) for plating solvents. Plating solvents may be understood as solvents selected from the group including, but not limited to, DOL (dioxolane), DME (dimethoxyethane), EC (ethylene carbonate), and DEC (diethyl carbonate), DMC (dimethyl carbonate), FEC (fluoroethylene carbonate), VC (vinylene carbonate), PC (propylene carbonate), HFE (hydrofluoroether), FEMC (trifluoroethyl methyl carbonate).

[0025] The present disclosure further relates to an electrode part for use in the electroplating process according to any one of claims 1 to 9, the electrode part comprising a current collecting element and an electrolyte coating provided thereon, the electrode part not containing a pre-deposited amount of anode metal, the electrolyte coating comprising: i) a first layer covering the current collecting element, containing one or more functional additives that form a solid electrolyte interfacial layer after reacting with the plated anode metal composition provided by electroplating, and ii) a second layer covering the first layer, which is relatively more resistant to solvent ingress from the plating solution than the first layer. As the part does not yet contain a quantity of highly reactive anode metal, the part can be stored under mild conditions for later use (e.g., subsequent plating and / or battery assembly) as a production part.

[0026] It will be appreciated that the electrode assembly may advantageously be configured as a double-sided electrode assembly with each of the electrolyte coatings provided on opposite sides of a current collecting element.

[0027] The present disclosure further relates to a battery comprising an electrode component preloaded with a layer of an anode metal composition. The preloaded electrode component is typically used as the so-called negative electrode of an anode metal battery, preferably a rechargeable anode metal battery, such as a lithium metal secondary battery (LMB). LBM advantageously provides higher energy density compared to secondary batteries using composite anode compositions such as LiC or LiSi as the electroactive composition.

[0028] The battery typically comprises a counter electrode part (as the positive electrode) located opposite the electrode part. In a preferred embodiment, the battery comprises a cathode composition provided along the face of the counter electrode part along the face facing the preloaded electrode part. Advantageously, a solid or semi-solid electrolyte may act as a separator element separating the anode from the cathode composition. Optionally, an electrolyte may be provided, for example impregnated with a liquid electrolyte. Alternatively or additionally, the battery may comprise an additional separator, for example a porous structure holding the electrolyte, to improve ion transport between the negative and positive electrode parts.

[0029] In a preferred embodiment, the battery is formed as a lithium metal ion secondary battery, and the cathode composition and the pre-loaded layer of the anode metal composition contain lithium. The pre-loaded lithium metal layer advantageously provides a buffer amount of lithium in addition to the lithium reserve provided by the cathode composition. The pre-loaded lithium metal layer advantageously functions as both a nucleation layer for subsequent anode metal plating (e.g., during initial and subsequent charging operations of the battery) and as a buffer to replace losses from the lithium reserve during at least the initial lithium metal plating and de-plating processes during operation of the battery. Compared to batteries without a pre-loaded metal layer (e.g., LMBs that require an initial internal plating process), the pre-loaded anode metal layer advantageously improves the safety of the battery by functioning as a nucleation layer that increases the life of the battery (replacing losses) while at the same time improving the homogeneity of the subsequent plated metal layers.

[0030] In another embodiment, the electrode component is used as a negative electrode in a lithium-sulfur secondary battery (LiS) or a lithium-air secondary battery (Li-air). In these embodiments, the layer of the anode metal composition can provide the lithium reserves of the battery.

[0031] These and other features, aspects, and advantages of the presently disclosed devices, systems, and methods will become better understood from the following description, appended claims, and accompanying drawings. [Brief description of the drawings]

[0032] [Figure 1A] FIG. 1 is a schematic exploded side view of a battery including an electrode component disclosed herein. [Figure 1B] 1 is a schematic side view of an electrode component disclosed herein. [Figure 2A] 1 is a schematic diagram of a method for manufacturing an electrode component disclosed herein. [Figure 2B] 1A-1C are diagrams illustrating an embodiment of the manufacture of an electrode component disclosed herein. [Figure 2C] FIG. 2 is a side view of a current collecting element. [Figure 2D] FIG. 2 is a side view of a current collecting element. [Figure 3A] 1A-1C are diagrams illustrating an embodiment of the manufacture of an electrode component disclosed herein. [Figure 3B] FIG. 13 shows aspects relating to rollers. [Figure 3C] FIG. 1 is a schematic diagram showing a method for manufacturing a battery. [Figure 4A] FIG. 11 is a detailed view of an aspect related to the manufacture of the electrode component. [Figure 4B] FIG. 1 is a schematic diagram illustrating one embodiment of a battery in use. [Figure 4C] FIG. 2 is a schematic diagram illustrating a further embodiment of a battery in use. [Figure 5A] 1A-1C illustrate further aspects of the manufacture of the electrode components disclosed herein. [Figure 5B] FIG. 2 illustrates an exemplary electrode part prior to preloading with an anode metal composition. [Figure 5C] FIG. 2 illustrates an exemplary electrode part prior to preloading with an anode metal composition. [Figure 5D] FIG. 2 illustrates an exemplary electrode part prior to preloading with an anode metal composition. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0033] The terminology used to describe certain embodiments is not intended to limit the invention. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly dictates otherwise. The term "and / or" includes any and all combinations of one or more of the associated listed items. It will be understood that the terms "comprises" and / or "comprising" specify the presence of the indicated features but do not exclude the presence or addition of one or more other features. Furthermore, when a particular step of a method is referred to after another step, it will be understood that this particular step may follow immediately after the other step, or one or more intermediate steps may be performed before performing the particular step, unless otherwise specified. Similarly, when a connection between structures or components is described, it will be understood that this connection may be established directly or through an intermediate structure or component, unless otherwise specified.

[0034] As used herein, the terms positive electrode or cathode and negative electrode or anode refer to terms commonly used to identify the electrodes of a battery during discharge operation. In a discharge battery mode, the anode is the "negative electrode" through which positive current flows from the cathode, which is the "positive electrode." During charging, these functions are reversed. Regardless of the charging mode, the electrochemical relationship can be characterized by charge exchange between the negative electrode material (anode composition) and the positive electrode material (cathode composition), where the negative electrode material has a lower work function or redox potential than the positive electrode material.

[0035] The term solid electrolyte should not be construed as being limited in definition to being composed solely of solid-state components. As expressed herein, it is contemplated, and even preferred, that electrolytes include non-solid components, such as liquids or wax-like materials, such as ionic liquids, succinonitrile, and / or organic solvents. Thus, the term solid electrolyte expressly includes semi-solid compositions, such as gels, or solid compositions impregnated with liquids and / or waxes.

[0036] Hereinafter, the present invention will be described more fully with reference to the accompanying drawings, in which embodiments of the present invention are shown. In the drawings, absolute and relative sizes of systems, components, layers, and regions may be exaggerated for clarity. The embodiments may be described with reference to schematic and / or cross-sectional illustrations of possible idealized embodiments and intermediate structures of the present invention. In the description and drawings, like numbers refer to like elements throughout. Relative terms and derivatives thereof should be construed as referring to the orientation shown in the drawings subsequently described or discussed. These relative terms are for convenience of description and do not require that the system be constructed or operated in a particular orientation, unless otherwise specified.

[0037] An embodiment of the present invention relates to a method for manufacturing an electrode component comprising a current collecting element and a coating of a solid or semi-solid electrolyte. In general, as shown for example in Figures 2A, 2B and 3A, the method comprises at least a step 300 of plating a quantity of an anode metal composition 30 as a layer between a current collecting element 10 and an electrolyte 20 covering the current collecting element 10. The anode metal composition is deposited between the electrolyte 20 layer and the current collecting element 10 by an electroplating process involving the directional transfer of corresponding ions, anode metal ions, from the plating electrolyte 302 through the electrolyte layer to the current collecting element 10. The most important aspects of the anode metal plating process are explained in more detail with reference to Figure 2B.

[0038] The anode metal composition typically comprises or consists essentially of one or more alkali metals selected from the group of lithium (Li), sodium (Na) and potassium (K). Lithium is preferred due to its relatively favorable redox potential and achievable power density. It is noted that the plating process differs from in situ anode metal plating processes in anode metal batteries (e.g., during the first charging cycle) in that in the closed context of the battery, the method of the present invention results in the formation (separate) electrode components with a pre-loaded amount of lithium metal, whereby lithium is obtained from an external source, whereas in the closed context of the battery, the lithium metal plated thereby is drawn from the overall lithium reserves in the battery. Importantly, the formed electrode components obtained by the electroplating method of the present invention differ from components produced in a process that includes deposition of the anode metal (e.g., lithium metal evaporation) prior to deposition of the solid or semi-solid electrolyte 20. As described in more detail herein below, the electrode components 1n formed according to the present disclosure differ most notably in that the deposited layer of anode metal is intrinsically covered by a previously deposited layer of electrolyte 20. This layer advantageously covers the underlying anode metal already from its deposition and during subsequent processing or storage steps, thereby eliminating unreacted alkali metals (e.g. Li metal, Li ) that are typically present in production drying chambers and even as unavoidable trace elements when processing is carried out under an inert atmosphere (e.g. argon). 0 The present invention mitigates the decomposition of the deposited anode metal (e.g., lithium) due to reaction with reactive species from the surrounding environment (e.g., O, N, and CO) that are known to react with lithium ions (which, unfortunately, makes production extremely complicated and expensive, even more so in industrial scale production).

[0039] The composite electrolyte is configured to allow transport of anode metal ions while being sufficiently rigid and hard to separate the anode component from the corresponding positive electrode (cathode). In some embodiments, the electrode component 1n can be incorporated into the battery structure, whereby the electrolyte 20 acts as a separator that electrically separates the anode from the opposing electrode 1p while allowing ion transport therebetween. The opposing electrode 1p includes an electronically conductive current collector 80 for providing / collecting electrons. The cathode current collector 80 can be provided, for example, as shown, as an electronically conductive film 81 on a carrier 82, preferably a flexible carrier.

[0040] In some embodiments, the negative electrode component may be incorporated into a battery structure 1000 that includes one or more separator structures 50 between the electrode component 1n and the counter electrode component 1p, as shown, for example, in Figure 1A. Alternatively, or additionally, the battery may include one or more electrolyte compositions, such as electrolyte 60, to improve ion transport between the cathode and anode.

[0041] In either case, the electrolyte 20 contains, at least prior to plating, one or more functional additives that react with the plated anode metal to form a layer of what is known in the art as a solid electrolyte interface (SEI). After plating, the additives participate in reactions with the anode metal to form the SEI. After plating, the amount of additive is significantly reduced and may even be essentially zero.

[0042] The electrolyte 20 layer is also generally resistant to the penetration of said solvents into it to avoid reaction of unreacted plated anode metal with solvents such as those contained in the plating electrolyte 302. The solid or semi-solid electrolyte 20 is generally a hybrid or composite electrolyte comprising a polymer matrix, a metal salt dispersed in the hybrid solid electrolyte, typically throughout the polymer matrix, and preferably one or more additives to improve anode metal ion conductivity.

[0043] The polymer matrix can be formed of any suitable composition. Typically, the matrix comprises one or more polymers known in the art, including, but not limited to, polyacrylates, polyethers, polyesters, polycarbonates, polyolefins, or copolymers thereof.

[0044] Thus, in some embodiments, the method includes a step 200 of coating the current collector 10 with a layer of composite solid electrolyte 20 prior to electroplating.

[0045] In a highly preferred embodiment, as shown, for example, in FIG. 1B, the electrolyte 20 is formed as a stack with at least two distinct layers including: i) a first layer 21 coating the current collecting element 10, at least initially containing one or more functional additives that form a solid electrolyte interface (SEI) 40 layer upon reaction with the plated anode metal composition 30; and ii) a second layer 22 coating the first layer 30 and that is resistant to inward penetration of solvents contained in the plating electrolyte towards the first layer and / or the plated anode metal composition 30. By providing separate layers, SEI formation is advantageously decoupled from resistance to inward penetration of solvents contained in the plating electrolyte. That is, the composition of the first layer, including the SEI-forming additives, can be adjusted independently of the composition of the second layer, which is resistant, or at least less permeable, to inward penetration of solvents contained in the plating electrolyte 302. Thus, the multilayer composite solid electrolyte comprises a first layer, an SEI-forming layer 21, and a second layer 22 that is resistant, e.g., essentially impermeable, or at least more resistant than the first layer, to the liquid electrolyte used for electroplating. Solvent resistance, or at least low permeability, can be advantageously achieved by selecting the matrix polymer and the solvent contained in the plating electrolyte 302. For example, the matrix polymers can be selected to be incompatible with each other depending on the solvent used in the plating electrolyte 302. For example, the matrix polymer contained in the electrolyte 20, and in particular in the second layer 22, can be selected to be poorly soluble or even essentially insoluble in the solvent, or at least to be preferably at least 50% less soluble than the polymer contained in the first layer 21 (including the SEI-forming additive). Preferably, the matrix polymer contained in the second layer has a solubility of 5% by weight or less, more preferably 5 g / kg or less, even more preferably 1 g / kg or less, in the solvent contained in the plating electrolyte 302 under plating conditions.

[0046] To maintain ionic conductivity throughout the electrolyte, both layers generally contain the corresponding anode metal salt. For lithium metal electrodes, these additives include Li salts such as LiTFSI (lithium bis(trifluoromethanesulfonyl)imide), LiClO4 (lithium perchlorate), LiFSI (lithium bis(fluorosulfonyl)imide), LiBF4 (lithium tetrafluoroborate), LiBOB (lithium bis(oxalato)borate), LiDFOB (lithium difluoro(oxalato)borate), LiTf (lithium trifluoromethanesulfonate), and / or LiTDI (lithium 2-trifluoromethyl-4,5-dicyanoimidazole).

[0047] In some embodiments, the electrode part comprises a further ion diffusion layer 23, as shown for example in FIG. 1B. The ion diffusion layer 23 is provided on the electrolyte 20 coating along the outer surface opposite the current collecting element 10. The ion diffusion layer 23 is provided on the electrolyte 20 prior to electroplating. The further ion conductive layer 23 has a composition and thickness that, when plated, contributes at least to the mitigation of the ingress of the solvent contained in the plating electrolyte 302 towards the electrolyte 20 and thus into the anode metal composition 30, while allowing metal ion transport. The layer typically comprises or is essentially formed from an inorganic or ceramic composition. Suitable compositions include aluminum oxide, titanium oxide, zinc oxide, and LiPON. Additionally (in the context of a battery), the ion diffusion layer 23, if provided, can insulate the anode metal layer from the solvent contained in the liquid battery electrolyte composition, e.g., the anolyte. The thickness of the ion diffusion layer 23 is generally thin enough to allow the passage of metal ions. The thickness is in the range of about 1-10 nm, preferably 1-5 nm, e.g. about 1-2 nm. It has been found that increasingly thicker layers progressively impede ionic conductivity while providing little additional benefit in terms of mitigating solvent intrusion. The ion diffusion layer 23 may be conveniently provided in a suitable thickness using known methods, including, but not limited to, dry vapor deposition methods such as PVD, CVD, and ALD, each of which may be advantageously combined with roll-to-roll processes, as disclosed herein.

[0048] SEI-forming additives known to form a stable SEI layer are generally known in the art. Additives include, but are not limited to, succinonitrile; ionic liquids, such as N-propyl-N-methylpyrrolidinium; lithium salts, such as lithium bis(trifluoromethanesulfonyl)imide, lithium bis(fluorosulfonyl)imide, lithium tetrafluoroborate, lithium dioxalatoborate, lithium fluoride, lithium hexafluoroarsenate, lithium hexafluorophosphate, lithium nitrate; or combinations thereof. Advantageously, the matrix polymer can be a polymer known to favorably contribute to SEI formation, including, but not limited to, polyethers, such as PEO or copolymers; and polycarbonates, such as polypropylene carbonate (PPC) or copolymers. J. Mol. Model. 23, Paper:6, (2017), incorporated herein by reference, describes several SEI-forming electrolyte additives for lithium-ion batteries. Typically, the SEI compositions formed for Li batteries include one or more of LiF, Li alkyl carbonate, Li2CO3, Li2O, Li alkoxide, etc. These compositions may be formed by reduction of electrolytes, solvents, and / or salts at the anode during battery formation. H. Wu et al. (Recent Progress in Understanding Solid Electrolyte Interphase on Lithium Metal Anodes, Advanced Energy Materials Vol. 11, No. 5, 2021, 2003092), incorporated herein by reference, provides an overview of materials, additives, and SEI formation on lithium metal anodes. The inventors have found that similar principles hold true in terms of additives, SEI formation, and its protective properties for anode metals other than Li (e.g., K and / or Na).

[0049] The second layer may contain similar, or even the same, metal salts, but typically in a different polymer matrix. This matrix may advantageously be specially tailored to resist permeation of the solvent contained in the plating electrolyte 302. In a preferred embodiment, the matrix polymer of the second layer comprises one or more of a polyfluorinated polymer, such as polyvinylidene fluoride (PVDF), PVDF-HFP, and polyacrylonitrile (PAN) or copolymers thereof. Alternatively, or additionally, the matrix polymer of the second layer may comprise one or more of polyamide, polypropylene, and polyethylene.

[0050] To further improve metal ion conductivity, the solid or semi-solid electrolyte 20, preferably at least the second layer, may contain one or more inorganic filler particles including one or more of a first type of filler particles comprising or consisting essentially of an inorganic dielectric composition and / or one or more filler particles of a second type comprising or consisting essentially of solid electrolyte particles such as LLZO, Li metal halides, LATP, etc.

[0051] The dielectric may be metal oxide or semi-metal oxide based, e.g., SiO2, TiO2, or combinations thereof. Preferably, the particles comprise or consist essentially of a high-k dielectric, i.e., a material having a dielectric constant well above about 4 over a temperature range of at least about 20°C to about 100°C. Preferably, the dielectric constant is 20 or greater, more preferably 40 or greater. Most preferably, the dielectric constant is greater than 100. Suitable materials include, but are not limited to, metal titanates (MTiOx), including, but not limited to, barium-based, strontium-based, calcium-based, copper-based, and yttrium-based titanates, and combinations and / or derivatives thereof, such as doped metal titanates. Preferred examples include barium titanate, strontium titanate, and combinations thereof. In addition to improving ionic conductivity, the incorporation of dielectric particles has been found to advantageously improve the homogenization of the electric field across the hybrid solid electrolyte layer. The inventors believe that the incorporation of dielectric fillers may homogenize the metal ion transport across the layer and / or reduce dendrite formation at the interface with the anode material as a result of repeated charge and discharge cycles. The inventors have found that the higher the dielectric constant, the better the homogenization. Preferably, the particles are primarily discrete particles homogenously dispersed within the hybrid solid electrolyte layer and / or its sublayers. In addition to matching the electric field, it has been found that the dielectric particles advantageously reduce the softening and / or glass transition temperature of the polymer matrix, thus contributing to the ionic conductivity of the hybrid solid electrolyte.

[0052] The electrolyte 20 generally has a thickness in the range of about 10-50 micrometers. Thicker layers improve protection of the underlying plated anode metal from the surrounding environment and from contact with the plating solution. The electrolyte 20 may be thicker, for example up to 100 μm or more, but the inventors have found that the benefits for the anode metal layer cannot be increased proportionately any more. The first layer (SEI-forming layer 21) generally has a thickness of more than 500 nm, preferably 1 μm or more or 2 μm or more, for example in the range of about 1-10 μm. Thinner layers may reduce the effectiveness of the SEI layer formed in terms of protecting the anode metal from decomposition by reaction with the surrounding environment. The second layer (solvent-resistant layer 22) typically has a thickness t22 of 5 μm or more, preferably 10 μm or more, for example in the range of about 10-40 μm.

[0053] The thickness of the formed anode metal layer can be advantageously adjusted to a desired specification by controlling one or more plating conditions, for example as described in more detail with reference to Figures 2B and 4A. In general, the thickness t30 of the deposited anode metal layer 30 depends on the intended application of the electrode component 1n. In some battery applications, the thickness of the anode metal layer, for example the lithium metal layer, can be adjusted within the range of 1 to 5 μm.

[0054] In some embodiments, the current collecting element 10, for example as shown in FIG. 1A, may be a metal element, for example a planar element such as a foil, formed of any metal composition that is stable (not involved in redox reactions) during battery operation. Typically, the metal may include, or even consist essentially of, copper or nickel. In other or further embodiments, for example as shown in FIG. 1B, the current collecting element 10 may be provided as an electronically conductive film 11, for example a copper film, provided along the surface of a carrier 12, for example a polymer or metal foil.

[0055] In a preferred embodiment, as shown for example in Figures 2A, 2B and 3A, the current collecting element 10 is formed as a flexible foil, for example as a metal or conductive film 11, on a flexible carrier 12. Typically the foil has a thickness in the range of 1-50 μm. Preferably the foil has a thickness in the range of 5-15 μm, which provides a good balance of flexibility and handling properties.

[0056] Thus, the method 100 may advantageously be configured as a roll-to-roll process. Advantageously, the current collecting elements may have an industrially reasonable width, for example up to 3 m, e.g., in the range of 0.3 to 2.5 m, allowing for mass production of pre-loaded electrode parts.

[0057] 2A shows a schematic of a method 100 of manufacturing an electrode component as disclosed herein configured as a continuous roll-to-roll process, in which a current collecting element 10 provided from a roll (left) is conveyed to a station for step 300 of plating, by electroplating, a quantity of anode metal composition 30 as a layer between the current collecting element 10 and an electrolyte 20 that coats the current collecting element 10.

[0058] Prior to plating, the method includes a step 200 of coating the current collector 10 with a layer of composite solid or semi-solid electrolyte 20. Although not shown in full detail, the solid electrolyte 20 is formed as a stack of two distinct layers including i) a first layer 21 that coats the current collecting element 10, at least initially containing one or more functional additives that form a solid electrolyte interface (SEI), and ii) a second layer 22 that coats the first layer 30 and is resistant to inward penetration of solvents contained in the plating electrolyte. Each of the layers included in the electrolyte 20 may be provided using methods known in the art, such as slot-die coating, extrusion, spin coating, dip coating, etc.

[0059] After step 300 of plating a quantity of anode metal composition 30, the formed preloaded electrode parts 1n are collected on a roller (far right in FIG. 2A) for storage. Optionally, the formed electrode parts may be cut into pieces for storage and / or directly processed, for example to manufacture batteries.

[0060] It will be appreciated that the method may alternatively be configured as a single wafer process.

[0061] 2B, 3A and 4A show electroplating 300, with FIG. 4A providing a more detailed view of the area marked in FIG. 2B.

[0062] In general, the plating process produces a metal coating, the anodic metal coating 30, on a current collecting element 10 via the reduction of cations of that metal with a direct current. The current collecting element 10 serves as the cathode (negative electrode) of an electrolytic cell, and the plating electrolyte is a solution containing a salt of the metal to be coated (e.g., a Li salt). The anode (positive electrode) is typically formed by an electrode containing the corresponding metal, usually a block of that metal or of some inert conductive material. The current is provided by an external power source.

[0063] 2B and 3A, current collecting element 10 having a coating of electrolyte 20 (shown as a single layer in FIG. 2B for clarity) is conveyed through an electrochemical plating bath 301. Once plating has resulted in the formation of a protective SEI layer, plating in particular, and the production process as a whole, may be conveniently carried out in a dry room environment without the need to reduce or eliminate O2, N2 and / or CO2 levels in the ambient atmosphere.

[0064] The bath 301 contains a liquid plating electrolyte 302 in which the film is impregnated. For Li metal plating, the electrolyte includes a lithium salt, such as one or more of LiTSI, LIFSI, LiNO3, LiF, LiClO4, LIF, LIBF4, LiBOB, LiDFOB, and LiPF6, and a solvent. The solvent is typically selected from one or more of ionic liquids, carbonates, ethers, fluorinated ethers, fluorinated carbonates, organic phosphates, solvents with sulfonyl groups, and ester solvents, such as DOL (dioxolane), DME (dimethoxyethane), EC (ethylene carbonate), and one or more of DEC (diethyl carbonate), DMC (dimethyl carbonate), FEC (fluoroethylene carbonate), VC (vinylene carbonate), PC (propylene carbonate), HFE (hydrofluoroether), FEMC (trifluoroethyl methyl carbonate). It will be appreciated that the selection of the solvent and components of the electrolyte 20, particularly the second layer 22, are selected relative to one another to avoid the penetration of the solvent into the solid or semi-solid electrolyte 20. The temperature of the bath during plating depends on the type of metal being plated. For lithium plating, the temperature is generally controlled to a temperature within the range of 20-80°C.

[0065] The plating electrolyte 302 is in contact with a source 310 of anode metal ions (e.g. Li ions). Optionally, the source may be the anode metal ions as provided by an amount of anode metal salt in the electrolyte itself. The anode metal salt then needs to be replenished periodically or continuously during plating to prevent anode metal ion depletion. Preferably, the source is provided by a solid source, e.g. a metal or metal oxide. This source may be connected as the cathode (negative electrode) of an electrolytic cell, which continuously replenishes the anode metal ions lost by plating onto the current collecting element 10 (connected as the anode of the cell).

[0066] In the case of lithium plating, the source may be a Li metal source. Advantageously, the source may include oxides, hydroxides or carbonates such as those commonly present on the surface of commercially available lithium metal (e.g., foils).

[0067] As shown in detail in FIG. 4A, the anode metal ions 31 transport through the solid electrolyte 20 layer for plating as an anode metal 40 layer onto the intervening anode metal composition 30. The plated anode metal (e.g., Li 0 ) with the SEI additive contained in the first layer 21 to form the SEI layer 40. The SEI layer allows further transport of the anode metal ions so that the anode metal can be plated through the SEI layer. Note that as the foil is transported (marked in FIG. 4A with direction D), areas A1 that initially do not have an anode metal layer become areas A2 that contain a preloaded amount of anode metal.

[0068] The SEI layer forms at the interface between the plated anode metal and the electrolyte 20. The formation of the SEI layer is stopped by the self-limiting nature of the SEI formation process or by consumption of the SEI-forming additives.

[0069] The SEI layer provides essential protection for the underlying anode metal and mitigates its decline in Li metal loss due to reaction with the surrounding environment. The electrolyte 20, particularly the second layer, protects the formed anode metal from reaction with the solvent contained in the plating electrolyte 302. Because both protective layers are present at the time of plating of the anode metal, the formed anode metal layer can be extremely pure and free of decomposition products compared to fabricated electrode components in which the electrolyte and / or SEI layer are deposited or generated only after the deposition of the anode metal is completed.

[0070] The thickness of the electrolyte 20 is preferably in the range of 10 to 50 μm. The first layer 21 containing the SEI-forming additive preferably has at least initially a thickness t21 in the range of 1 to 10 μm. The second layer resistant to the penetration of the solvent contained in the plating electrolyte 302 typically has a thickness in the range of 10 to 40 μm. The formed SEI layer can advantageously be a conformal coating layer having a thickness of more than about 1 μm. More preferably, it is thicker, for example 2 μm or more, for example in the range of 1 to 5 μm, in the range of 2 to 5 μm, in the range of 1 to 10 μm, or in the range of 2 to 10 μm.

[0071] Anodic metal (e.g. Li) plating is based on known principles. Plating can be carried out in direct current, pulse, or reverse pulse mode. The amount of plated anode metal layer can be conveniently controlled by controlling one or more plating conditions.

[0072] In a preferred embodiment, the method includes controlling the amount, e.g., thickness (t30), of the electroplated anode metal layer 30 by one or more of adjusting the magnitude, duration and / or pulse shape of the electroplating current I during electroplating and / or by controlling the contact time of the substrate with the plating electrolyte, preferably by a controller C. Thus, the electrode component (1n) can be provided with a specific amount of anode metal, e.g., a predetermined target amount.

[0073] For example, in the case of a rechargeable anode metal-ion battery as shown in FIG. 1A, the thickness of the anode metal mass is preferably 1 μm or more, more preferably 2 μm or more, for example 5-10 μm. Optionally, up to 50 μm or even 100 μm. The thicker the anode metal layer, the greater the buffer capacity of the battery and the longer the operating life may be. Thinner layers are possible, but may provide a smaller and / or more discontinuous buffer capacity and may provide reduced performance in terms of homogenization of the plated anode metal during battery charging operation.

[0074] For Li-S or Li-air secondary batteries, such as those shown in Figures 4B and 4C, the anode metal layer dictates the lithium reserve of the battery, and therefore the amount of preloaded anode metal per unit area is typically larger, such as 50 μm or more, preferably 100 μm or more, such as between 1 and 200 μm or more.

[0075] Preferably, the source is in the form of a roller, for example as shown in Figures 2B, 3A and 3B, e.g. a roller with a body 313 covered with a film or layer (e.g. foil) as the anode metal source 311. Preferably, the roller and / or the transport system is configured to adjust the position of the relative separation distance between the source and the current collecting element 10, for example by mounting the roller on an adjustable holder 314 as shown.

[0076] In a preferred embodiment, the rollers and / or system source and / or rollers are adjustable such that the source can be in direct contact with the outer surface 20f of the electrolyte 20 during operation. Adjusting the separation distance between the source and the electrolyte 20 to direct contact advantageously reduces the ion diffusion path length between the source and the current collecting element 10. Adjustable rollers can also advantageously maintain the separation distance, e.g., direct contact, between the roller and the electrolyte coating 20 even as the anode metal on the roller is consumed.

[0077] In some embodiments, the roller is patterned to include portions without anode metal source, for example as shown in Figure 2B. Patterning the source, for example by including gaps 311g without anode metal source at the periphery of the roller, can advantageously result in electrode parts 1n that include areas with reduced thickness of the plated anode metal layer, or even gaps without plated anode metal.

[0078] In some embodiments, the substrate foil is guided between a pair of rollers 310, 320 configured to apply compressive pressure on the formed layer of anode metal composition 30 during plating. Preferably, it is guided between an adjustable counter roller 320 opposed to the anode metal roll.

[0079] By applying contact pressure to the foil as a layer on the anode metal is deposited, it is advantageous to prevent the deposition of the deposited anode metal, e.g. Li 0 The porosity of the plating electrolyte 302 may be reduced. Furthermore, such a configuration may be used to facilitate the electric field applied to the plating points. Furthermore, by applying contact pressure to the foil as the layer on the anode metal is deposited, the overall volume of the plating electrolyte 302 may be advantageously reduced.

[0080] In some embodiments, as shown for example in Figure 2B (depicting the roller a distance away from the foil), an elastomeric layer 312 is provided around the body 313 of at least one of the rollers 310. The elastomeric layer may advantageously homogenize the applied contact force, for example by reducing spike forces due to surface roughness.

[0081] In another or further preferred embodiment, the foil is wrapped around a portion of the circumference of the plating roller, as shown in FIG. 5A. Wrapping the foil around a portion of the roller creates an overlap with an increased contact area with the roller, compared to the relatively narrow or line contact as shown in FIG. 3A. Wrapping the foil around a portion of the roller can advantageously increase the contact time (plating time) between the foil and the roller at a given conveying speed. Increasing the contact time can advantageously reduce the areal plating speed. The length L of the overlap can be varied, for example, by positioning a movable roller. In some embodiments, the overlap can be 10% or more, such as 20% or more, or 30% or more, up to about 50% or more, such as up to about 75%, of the outer surface of the roller by using one or more additional guide rollers.

[0082] In a preferred embodiment, the plating speed is set at 5 μm / hour or less. It has been found that lower plating speeds provide more consistent and uniform plating. The best lithium anode metal quality has been seen at plating speeds of 1 μm / hour or less.

[0083] In yet another or further preferred embodiment, a porous separator 315 is provided between the roller 310 and the substrate, e.g., foil, during plating. The separator may advantageously reduce the overall volume of plating electrolyte 302 in the bath, or may even essentially contain the overall amount of plating electrolyte 302. In some embodiments, the porous separator is provided as a temporary layer on the solid or semi-solid electrolyte 20. Alternatively, or additionally, the separator may be provided as a separate sheet between the foil and the roller, and may be transported together with the foil, e.g., by a roller, preferably an anode metal roller. FIG. 3A shows a plating process in which the separator 315 is transported together with the foil 10, 20 by the anode metal roller 310. In a preferred embodiment, the separator 315 is transported as an attracting loop, preferably with one or more adjustable tension rollers 318, e.g., as shown. Note that in the illustrated embodiment, the anode metal roller 310 and the counter roller 320 are adjusted to contact the foil. A controller C is provided to maintain the contact pressure. The position of the rollers 310, 320 can be adjusted to maintain contact with the foil while the anode metal 311 is consumed over time.

[0084] Further, alternatively, or additionally, the separator may be configured as a layer 315 along the outer surface of roller 310, as shown, for example, in FIG. 3B.

[0085] By providing the working electrolyte to a porous separator, either along the surface of the roller or as a separately transported sheet 315, the need to remove the separator from the product after processing is alleviated. Preferably, the separator is a compressible separator (elastic). Providing a compressible (elastic) separator advantageously improves contact with the electrolyte 20 and may reduce / buffer peak forces due to, for example, unevenness on the roller and / or product.

[0086] It will be appreciated that for plating one or more other or additional anodic metals (eg, Na or K), the plating source, plating electrolyte, and conditions will be adjusted appropriately.

[0087] In some embodiments, the plating may be essentially a dry plating process. The dry plating process may be realized by the use of a dry or semi-dry plating electrolyte layer or belt between the foil and the anode metal source. The dry or semi-dry plating process reduces or eliminates adverse reactions between the solvent and the plated anode metal. In some variations, the dry or semi-dry electrolyte may be a solid or semi-solid electrolyte layer 316 provided around the plating roller, for example as shown in FIG. 5A. In other embodiments, the dry or semi-dry electrolyte may be provided as a sheet or belt between the roller and the foil. It will be understood that a small amount of liquid electrolyte may be provided as a wetting agent to improve contact with the foil. When using a dry or semi-dry plating process, the second electrolyte layer may be understood as providing structural integrity to the stack. In particular, the second layer 22 (compare FIG. 4A) may be understood as being formed of a relatively harder composition than the first layer (e.g., a relatively harder polymer or even ceramic layer as disclosed herein). This allows the first layer to be relatively soft, or even a gel, which is beneficial in reducing damage caused by contact forces during dry or semi-dry plating. A gelatinous first layer is particularly envisioned in conjunction with conforming the 3D structure to the current collector, e.g., as discussed with reference to Figures 2C-D and 5C.

[0088] In addition to, and as an alternative to, plating from an external source, the electrode components disclosed herein may also be used to serve in battery products without providing an electrode with a preloaded amount of anode metal (e.g., lithium). In such applications, after an initial battery charging operation, a plating electrolyte and anode metal source, such as, for example, a cathode composition and a solid electrolyte from which the anode metal is plated, may be provided in situ within the battery.

[0089] In some preferred embodiments, one or more inorganic layers 25 are provided on the second layer 22 of the electrolyte coating 20, as shown, for example, in FIG. 5B. Alternatively or additionally, one or more further inorganic layers may be provided between the first layer 21 and the second layer 22 of the electrolyte coating 20. The inorganic layer or layers 24, 25 may further reduce crosstalk between the first layer and the plating environment. The inorganic layers may, but need not, be of the same or similar composition. In either case, the ceramic layer will be transgressive to the anode metal salt (alkali or alkaline earth ions, for example lithium ions). Conductivity of the anode metal ions, for example Li ions, may be achieved by a suitably thin (for example 5 nm or less) composition, or a composition that is inherently anode metal ion conductive, for example LiPON.

[0090] 5B, 5C and 5D show exemplary electrode parts 1n' before preloading with an anode metal composition. Before preloading by electroplating means that the electrode parts can be understood to be essentially free of anode metal. These parts can therefore be understood as starting products of the plating process described herein. Consistent with the present disclosure as a whole, these parts comprise at least a current collecting element 10 and an electrolyte coating 20. The electrode parts do not comprise a pre-deposited amount of anode metal. The electrolyte coating comprises i) a first layer 21 covering the current collecting element 10 containing one or more functional additives that form a solid electrolyte interface 40 layer after reaction with the plated anode metal composition 30 provided by electroplating, and ii) a second layer 22 covering the first layer as disclosed herein. The second layer can be understood to be more resistant than the first layer to the penetration of plating solvents, particularly solvents used in subsequent electroplating.

[0091] In some embodiments, a thin ceramic layer 24 is provided between the first layer 21 and the second layer 22 of the electrolyte coating to further mitigate solvent ingress and / or solvent exchange to / from the second layer while allowing Li-ion transfer. In other or further embodiments, the thin ceramic layer 24 mitigates solvent ingress and / or exchange while allowing Li-ion transfer. In further embodiments, the second layer 22 is sandwiched between the first and second ceramic layers, for example as shown. In addition to mitigating solvent ingress / exchange, the ceramic layer can increase the stiffness of the electrolyte coating 20. This can be particularly beneficial when the current collecting element 10 is a 3D structured current collector comprising a plurality of outwardly extending elongated protrusions 10p in combination with a gel-like or semi-solid first layer.

[0092] In another or further variation, a double-sided coated anode is provided: Figure 5D shows an anode part 1n' (before electroplating) having a double-sided coated current collecting element comprising a carrier foil 12 coated on opposite sides with respective electronically conductive metal films 11-1, 11-2 (each comprising a respective electrolyte coating 20-1, 20-2 as disclosed herein).

[0093] These double-sided electrodes can be used to advantage in the assembly of battery cell stacks. Depending on the nature of the subsequent coating layer provided on either side, e.g., the cathode or anode, these double-sided electrodes can be used in the assembly of series or bipolar cell stacks.

[0094] In some preferred embodiments, the electrode part 1n comprises a nucleation layer 15, as shown in FIG. 1B. A nucleation or alloying layer applied directly to the current collecting element 10, for example on the metal coating 11 as shown, may advantageously improve the homogeneity of the anode metallization layer formed thereon during subsequent electroplating. It is believed that the nucleation layer functions as a wetting layer between the current collecting element 10 and the anode metal composition 30. In the case of lithium-based batteries, the seed layer may be referred to as lithophilic. In the case of other metals, the layer may be referred to as, for example, sodium- or potassium-philic. The seed layer generally comprises or consists essentially of an electronically conductive composition, including, but not limited to, one or more of Zn, Sn, In, Mg, Al, Ti, Mo, Cr, carbon-graphite, graphite-like, and the like. It is believed that the wetting effect is due, at least in part, to the seed layer composition alloying with the anode metal composition. If such an alloying layer is relatively thin (e.g., 10 nm to 500 nm), it may be considered a seed layer. When the layer is thicker (e.g., up to 20 μm), it can be considered a host material for the anode metal. The anode metal layer then provided can be considered an alloy of one or more anode metals with the seed composition (e.g., Sn-Li, In-Li, Zn-Li, etc., when lithium is used as the anode metal). In either case, the seed / alloying layer allows for homogeneous anode metal deposition on the current collecting element, improving cell performance and reliability.

[0095] Optionally, the seed composition may be an oxide thereof, e.g., a hydroxide thereof, e.g., ZnO. x These oxides are reduced by contact with the relatively more electropositive anodic metal composition.

[0096] The seed layer 15 is typically provided directly prior to deposition of the electrolyte 20. Suitable methods include ALD, PVD, CVD, and electroplating. In the case of a structured current collecting element 10, conformal layer deposition methods such as ALD and / or electroplating may be preferred, e.g., as discussed in connection with Figures 2C and 2D. Optionally, a nucleation layer may be plated through the electrolyte layer 20 or another solid electrolyte layer.

[0097] The present disclosure further relates to an electrode part preferably obtainable by the method disclosed herein, in particular comprising a current collecting element provided thereon with a solid or semi-solid electrolyte layer and a preloaded amount of an anode metal composition provided as a layer between the current collecting element and the electrolyte.

[0098] Furthermore, the present disclosure relates to an energy storage device, such as a battery, comprising the electrode components (1n), and to a method for manufacturing such a device.

[0099] 1A, a preloaded electrode part 1n is shown comprising an anode metal composition 30 provided as a layer between a current collecting element 10 and a solid electrolyte layer 20. As shown in more detail in FIG. 1B, a solid electrolyte interface (SEI) layer 40 is formed along the interface between the electrolyte and the layer of anode metal composition 30.

[0100] In a preferred embodiment, for example as shown, the electrolyte 20 comprises i) a first layer 21 covering the current collecting element 10 and ii) a second layer 22 covering the first layer. The SEI layer as obtained by the disclosed method can advantageously have a thickness (t30, see FIG. 4A) within a range in which the electrode can be fabricated in a dry room environment. As detailed with reference to the method, the first layer contains one or more functional additives for forming a solid electrolyte interface 40 layer by reaction with the plated anode metal composition 30 at least prior to plating. The second layer is resistant to inward penetration of solvents contained in the plating electrolyte 302 towards the plated anode metal composition 30.

[0101] The electrodes may be characterized by reduced decomposition and / or homogeneity of the preloaded anode metal due to a protective SEI layer formed directly with the deposition of the anode metal. In contrast, electrodes with a preloaded anode metal layer that is deposited prior to the formation of the SEI layer have relatively large Li losses and / or corresponding inhomogeneity due to reaction products with the surrounding environment, e.g., air.

[0102] In some embodiments, the electrode component 1n comprises a seed layer 15, as shown for example in FIG. 1B.

[0103] Advantageously, the preloaded electrode parts In may be flexible, for example foil, as described in connection with Figures 2A and 2B.

[0104] In some embodiments, the current collecting element is a 3D structural element comprising a plurality of elongated outwardly extending protrusions. FIG. 2C shows an exemplary current collecting element 10 comprising protrusions 11p extending outwardly from a conductive base 11b. The base may be a metal foil or film. Alternatively or additionally, the base may be provided on a carrier, for example a flexible carrier 12. The base with protrusions, for example in the form of pillars or columns, forms a scaffolding structure on which a coating of solid or semi-solid electrolyte 20 is deposited. The structure thus serves to retain the amount of anode metal composition deposited by plating.

[0105] Preferably, the protrusions are electrically conductive at least along the outer surface (e.g., sidewalls) to improve current transport to / from the base. The formed pre-loaded 3D electrodes advantageously provide improved performance in terms of capacity and speed.

[0106] It will be appreciated that when the electrolyte 20 is provided as a multi-layer stack, the first layer 21, including the SEI additive, preferably extends into the 3D current collector, while the second layer 22, the solvent resistant layer, is preferably provided as a planar coating layer (not extending between the pillars), as shown, for example, in FIG. 2D.

[0107] Optionally, the electrolyte may be formed as a single layer that is resistant to inward penetration of solvents contained in the plating electrolyte and that includes the SEI-forming additive.

[0108] Exemplary embodiments of an energy storage device comprising the electrode component 1n disclosed herein and a method for manufacturing such a device will now be described with reference to FIGS. 1A, 3B and 3C.

[0109] FIG. 3C shows a schematic diagram of a method 500 for manufacturing a battery 1000. The method includes step 501 of providing an electrode part 1n as disclosed herein with a preloaded amount of anode metal, and step 510 of assembling the parts as a battery structure on the opposite side of a counter electrode part 1p. As described in relation to FIG. 1A, the method may further include one or more steps of providing one or more additional separator 50 structures between the electrode part 1n and the counter electrode part 1p. Alternatively or additionally, the method may include providing one or more electrolyte compositions, such as an electrolyte 60, to improve ion transport between the cathode and the anode.

[0110] 1A, 4B and 4C show an exemplary embodiment of a battery 1000 comprising an electrode part 1n and a counter electrode part 1p as disclosed herein.

[0111] In some preferred embodiments, for example as shown in Figures 1A and 2B, the cell includes a cathode composition 70 provided along a surface of the counterelectrode component 1p.

[0112] In a particularly preferred embodiment, the battery is formed as a lithium metal ion secondary battery, and both the cathode composition 70 and the pre-loaded layer of the anode metal composition 30 contain lithium. It is noted that the pre-loaded lithium metal layer may advantageously provide a buffer amount of lithium in addition to the lithium reserve provided by the cathode composition. The pre-loaded lithium metal layer functions as a nucleation or plating layer for the lithium metal subsequently plated in situ (e.g., during initial or subsequent charging operations) and as a buffer to replace losses from the lithium reserve composition during at least the initial lithium metal plating and de-plating processes during operation of the battery. The composition of the cathode composition and the method of providing the cathode composition 70 are well known in the art. Suitable compositions include lithium metal salts, such as LiM oxide compositions or lithium metal sulfide (LiM-S) compositions. For example, Li-loaded ceramics, such as Li x M y O z Or Li a M b PO4 (wherein M is typically one or more of Co, Ni, Al, Mn, Fe, and Sn).

[0113] In other embodiments, the available anode metal loading is determined primarily, or even exclusively, by the amount of preloaded anode metal with which lithium metal layer 30 is preloaded.

[0114] FIG. 4B shows a lithium secondary cell formed as a lithium-sulfur (Li-S) secondary cell. The electrode component 1n is separated from the counter electrode comprising a positive electrode current collector structure 80 having a sulfur cathode (S8) cathode composition by an additional separator 50. The additional separator 50 is optional in view of the electrolyte coating 20 provided on the current collector element 10. However, the additional separator 50 can be applied to improve ion transport between the anode and the cathode. The cell is shown in a discharge cycle, during which electrons from the lithium oxidation reaction at the anode are transferred to the cathode via an external load. Lithium ions in the electrolyte are transferred to the cathode where sulfur is reduced to lithium sulfide (Li2S). During a charge cycle, sulfur is again oxidized and lithium ions are again transferred to be reduced at the anode.

[0115] FIG. 4C shows the current flow of electrons e marked as "I" using the oxidation of lithium at the anode and the reduction of oxygen at the cathode. - 1 shows a lithium secondary battery configured as a lithium-air (Li-S) secondary battery inducing a flow of . As with Li-S batteries, the anode metal (lithium) inventory in the battery is determined primarily, or even exclusively, by the amount of pre-loaded anode metal (lithium) that is cycled between the anode and cathode during each charge and discharge operation.

[0116] The battery is shown in a partially charged state during a charging cycle (with optional additional separator 50) whereby a portion of the lithium reserves is in a reduced state (metallic state) in the anode 30' and the remaining portion is contained in an oxidized form 70' in the cathode.

[0117] It will be understood that, although features are described herein as part of the same or separate embodiments for clarity and conciseness of description, the scope of the invention may include embodiments having all or a combination of any of the described features. Of course, it should be understood that any of the above-described embodiments or processes may be combined with one or more other embodiments or processes to provide further improvements in design and advantage discovery and adaptation.

[0118] Unless specifically stated otherwise, in interpreting the appended claims, the term "comprising" does not exclude the presence of elements or acts other than those recited in a given claim, the term "a" or "an" preceding an element does not exclude the presence of a plurality of such elements, and any reference sign in a claim does not limit its scope, and it should be understood that several "means" may be represented by the same or different items or implemented structures or functions, and any of the disclosed devices or parts thereof may be combined together or separated into further parts. When one claim refers to another claim, this may indicate synergistic advantages achieved by the combination of their respective features. However, the mere fact that certain measures are recited in mutually different claims does not indicate that a combination of these measures cannot also be advantageously used. Thus, the present embodiments may include all practical combinations of the claims, and each claim may in principle refer to any preceding claim unless the context clearly excludes otherwise. [Explanation of symbols]

[0119] 1n electrode parts 1n' Electrode parts, anode parts 1p Electrode, Counter Electrode Parts 10 Current collecting element, current collector, foil 11 Electronically conductive films, conductive films, metal coatings 11b Conductive base 11p protrusion 12 Carrier, flexible carrier 20 Electrolytes, composite solid electrolytes, composite solid or semi-solid electrolytes, solid electrolytes, foils, electrolyte coatings, solid electrolyte layers, solid or semi-solid electrolytes 20f External surface 21 First layer, SEI formation layer 22 Second Layer 23 Ion diffusion layer, ion conduction layer 24 Inorganic layer, thin ceramic layer, thin ceramic layer 25 Inorganic layer 30 Anode metal composition, anode metal coating, lithium metal layer 30' Anode 31 Anode metal ions 40 Solid electrolyte interface (SEI), anode metal, SEI layer, solid electrolyte interface (SEI) layer 50 Separator structure, separator 60 electrolytes 70 Cathode Composition 80 Electronically conductive current collector, cathode current collector, and positive current collector structure 81 Electronically Conductive Film 82 Carrier 100 ways 200 Coating process 300 Plating process 301 Electrochemical plating bath 302 Plating electrolyte, liquid plating electrolyte 310 Source, roller, anode metal roller 311 Anode metal source, anode metal 312 Elastomer layer 313 Main unit 314 Adjustable Holder 315 Porous separators, separators, sheets 316 Solid or semi-solid electrolyte layers 318 Tension Roller 320 Roller, counter roller 500 ways 501 Providing process 510 Assembly process 1000 battery structure, battery

Claims

1. A method (100) for manufacturing an electrode component (1n) comprising a current collecting element (10) and an electrolyte coating (20), comprising the steps of: depositing (300) a quantity of an anode metal composition (30) as a layer between a current collecting element (10) and an electrolyte (20) coating the current collecting element (10) by an electroplating process involving directional transfer of anode metal ions (31) from a plating electrolyte (302) through an electrolyte coating onto the current collecting element (10); 1. A method (100) in which an electrolyte coating (20) comprises: i) a first layer (21) coating a current collecting element (10) that at least initially contains one or more functional additives that form a solid electrolyte interfacial (40) layer upon reaction with a plated anode metal composition (30); and ii) a second layer (22) coating the first layer that is more resistant than the first layer to inward penetration of a solvent contained in the plating electrolyte (302) toward the plated anode metal composition (30).

2. depositing a first electrolyte composition or a precursor thereof onto a current collecting element (10) to form a first layer (21); depositing a second electrolyte composition or a precursor thereof onto the deposited first layer to form a second layer (22); The method of claim 1 , comprising:

3. 3. The method according to claim 1 or 2, wherein the current collecting element (10) is formed as a flexible foil and the method is configured as a roll-to-roll process including conveying the foil through a station (301) configured for input of the foil into a conveying section by an electroplating process.

4. 4. The method according to any one of claims 1 to 3, wherein the anode metal source (311) is an anode metal roll, preferably a lithium metal roll (310).

5. 5. The method according to any one of claims 1 to 4, comprising controlling, preferably by a controller (C), the amount, e.g. thickness (t30), of the anode metal layer (30) electroplated in accordance with a predetermined target by one or more of adjusting the magnitude, duration and / or pulse shape of the electroplating current (I) during electroplating and / or by controlling the contact time of the substrate with the plating electrolyte.

6. 6. The method according to claim 1, further comprising, prior to the step of depositing the anode metal composition (300) and prior to providing the electrolyte coating, a step of coating the current collecting element (10) with one or more layers (15) of a composition that alloys with the anode metal composition (30).

7. 7. The method according to any one of claims 1 to 6, wherein during electroplating the substrate (10) is guided between a pair of rollers (310, 320), preferably an anode metal roll and an opposing counter roller configured to apply a compressive pressure on the formed layer of the anode metal composition (30).

8. 8. The method of any one of claims 4 to 7, wherein a porous separator (315) is provided between the anode metal roll (310) and the electrolyte (20) during plating.

9. 9. The method of any one of claims 1 to 8, comprising providing an ion diffusion layer (23) on the electrolyte (20) along an opposite exterior surface of the current collecting element (10), the ion diffusion layer (23) comprising a composition configured to further resist ingress of a solvent contained in the plating electrolyte (302) into the electrolyte (20).

10. Electrode part (1n) preferably obtainable by a method according to any one of claims 1 to 9, A current collecting element (10) provided thereon with an electrolyte coating (20), the electrolyte coating comprising: i) a first layer (21) coating the current collecting element (10), optionally containing one or more functional additives that form a solid electrolyte interface (40) layer after reaction with a plated anode metal composition (30) provided by electroplating; and ii) a second layer (22) coating the first layer, the second layer being more resistant to plating solvents than the first layer; a preloaded amount of an anode metal composition (30) provided as a layer between the current collecting element (10) and the electrolyte coating (20); a solid electrolyte interfacial surface (40) formed as a layer along the interface between the electrolyte coating and the layer of anode metal composition (30); An electrode part (1n).

11. Electrode part (1n) according to claim 10, wherein the current collecting element (10) is a flexible foil.

12. 12. The electrode part (1n) according to claim 10 or 11, wherein the current collecting element (10) comprises a plurality of elongated projections (11p) extending outwardly from the conductive base (11b).

13. 10. An electrode part (1n') for use in an electroplating process according to any one of claims 1 to 9, comprising A current collecting element (10); an electrolyte coating (20) provided thereon; Equipped with The electrode component does not include a pre-deposited amount of anode metal, and the electrolyte coating comprises: i) a first layer (21) coating the current collecting element (10) containing one or more functional additives that form a solid electrolyte interface (40) layer after reaction with a plated anode metal composition (30) provided by electroplating; and ii) a second layer (22) coating the first layer, the second layer being more resistant to plating solvents than the first layer. Electrode part (1n').

14. 14. The electrode assembly according to claim 10, which is a double-sided electrode assembly, in which each of the electrolyte coatings is provided on both sides of the current collecting element.

15. A method (500) for manufacturing a battery (1000), comprising: A step of manufacturing an electrode part (1n) as defined in any one of claims 1 to 9; Assembling the obtained part on the opposite side of the counter electrode part (1p); The method (500) comprising:

16. A battery (1000) comprising an electrode part (1n) according to any one of claims 10 to 14 and a counter electrode part (1p) located opposite the electrode part (1n).

17. 17. The battery (1000) of claim 16, wherein the battery is formed as a lithium metal ion secondary battery, and wherein the pre-loaded layer of the anode metal composition (30) comprises lithium, and the battery further comprises a lithium ion-containing cathode composition (70), whereby the pre-loaded lithium metal layer provides a buffer amount of lithium in addition to the lithium reserve provided by the cathode composition.

18. 17. The battery (1000) of claim 16, wherein the battery is configured as a lithium-sulfur secondary battery or a lithium-air secondary battery, and the layer of anode metal composition (30) comprises lithium that provides the overall lithium inventory of the battery.

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