Method of forming a sintered composition and energy device

Abstract

A method of forming a sintered composition includes providing a slurry precursor including a lithium-, sodium-, or magnesium-based compound; tape casting the slurry precursor to form a green tape; and sintering the green tape at a temperature in a range of 500 °C to 1350 °C over a time in a range of less than 60 min to form the sintered composition, wherein the slurry precursor further includes a solvent and a dispersant. The dispersant can include an amine compound, a carboxylic acid compound, or a combination, mixture, or salt thereof.

Description

Technical Field

[0001] This application claims priority and benefit to U.S. Patent Application No. 17 / 407,677, filed August 20, 2021, with the United States Patent and Trademark Office, the entire contents of which are incorporated herein by reference.

[0002] This disclosure relates to sintered lithium cobalt oxide electrodes for use in Li-ion batteries. Background Technology

[0003] Lithium cobaltite (LCO) (LiCoO2) is used in most commercial Li-ion batteries (LIBs) due to its relatively high theoretical specific capacity (e.g., about 274 mAh / g), high theoretical volumetric capacity (e.g., about 1363 mAh / cm3), low self-discharge, high discharge voltage, and good cycle performance.

[0004] Typically, LIB cathodes are fabricated by incorporating oxides or carbonaceous powders into an organic binder, and this process is performed via a slurry-based coating procedure. However, challenges remain in the LCO ribbon forming and sintering process, such as poor dispersibility in the solvent, slurry wetting resistance on the carrier film, and ribbon burning during binder burnout. These issues result in insufficient density characteristics in the final cathode, thereby affecting the energy density of the LIB.

[0005] This disclosure reports a novel formulation that addresses LCO dispersion, slurry wetting issues, and strip combustion problems, as well as continuous forming and rapid sintering for manufacturing sintered LiCoO2 electrodes. Summary of the Invention

[0006] In some embodiments, the method of forming a sintered composition includes: providing a slurry precursor comprising a lithium, sodium, or magnesium-based compound; strip forming the slurry precursor to form an unprocessed strip; and sintering the unprocessed strip at a temperature in the range of 500°C to 1350°C for a time in the range of less than 60 min to form the sintered composition, wherein the slurry precursor further comprises a solvent and a dispersant.

[0007] In one aspect that can be combined with any other aspect or embodiment, the dispersant comprises an amine compound, a carboxylic acid compound, or a combination thereof, a mixture thereof, or a salt. In one aspect that can be combined with any other aspect or embodiment, the amine compound comprises oleylamine, dibutylamine, or a combination thereof. In one aspect that can be combined with any other aspect or embodiment, the amine compound comprises at least one amino group, at least one imine group, or a combination thereof, wherein the at least one amino group or at least one imine group contains an alkyl chain or an aromatic ring, and wherein the amine compound has fewer than 30 carbon atoms. In one aspect that can be combined with any other aspect or embodiment, the carboxylic acid compound comprises oleic acid. In one aspect that can be combined with any other aspect or embodiment, the carboxylic acid compound comprises an R-COOH structure molecule, wherein R is an alkyl chain or an aromatic ring, and wherein the R-COOH structure molecule has fewer than 30 carbon atoms. In one aspect that can be combined with any other aspect or embodiment, the dispersant comprises a combination, mixture, or salt of an amine compound and a carboxylic acid compound, and wherein the ratio of the carboxylic acid compound to the amine compound is 0:1 to 1:0. In one aspect that can be combined with any other aspect or embodiment, the ratio of the carboxylic acid compound to the amine compound is 1:3 to 3:1. In another aspect that can be combined with any other aspect or embodiment, the ratio of the carboxylic acid compound to the amine compound is at least 1:4.

[0008] In one aspect that can be combined with any other aspect or implementation, the lithium, sodium, or magnesium-based compound has a D50 particle size of up to 0.6 μm.

[0009] In one aspect that can be combined with any other aspect or embodiment, the solvent includes 1-methoxy-2-propanyl acetate (MPA), isopropanol (IPA), ethyl isobutyrate (EIB), ketones, aromatic hydrocarbons, amines, nitrated hydrocarbons, chlorinated hydrocarbons, or combinations thereof. In another aspect that can be combined with any other aspect or embodiment, the solvent is nonpolar and has a dielectric constant of less than 20 at 20°C.

[0010] In one aspect that can be combined with any other aspect or embodiment, the lithium-based compound includes at least one of the following: lithium cobaltite (LCO), lithium manganite spinel (LMO), lithium nickel cobalt aluminate (NCA), lithium nickel manganese cobalt oxide (NMC), lithium iron phosphate (LFP), lithium cobalt phosphate (LCP), lithium titanate, lithium niobium tungstate, lithium titanium sulfide, or combinations thereof. In one aspect that can be combined with any other aspect or embodiment, the lithium, sodium, or magnesium-based compound is at least 50 wt.% of the total slurry precursor. In one aspect that can be combined with any other aspect or embodiment, the sodium or magnesium-based compound includes at least one of the following: NaVPO4F, NaMnO2, Na... 2 / 3 Mn 1-y Mg y O2(0 <y<1)、Na2Li2Ti5O 12 Na2Ti3O7, MgCr2O4, or MgMn2O4.

[0011] In one aspect that can be combined with any other aspect or implementation, the slurry precursor further comprises at least one of a binder and a plasticizer.

[0012] In one aspect that can be combined with any other aspect or embodiment, the strip forming includes: forming a slurry precursor into a sheet configuration having a thickness in the range of 5 μm to 100 μm; and drying the sheet configuration such that the combination of at least one solvent, dispersant, and plasticizer does not exceed 10 wt.% of the dried sheet. In one aspect that can be combined with any other aspect or embodiment, the method further includes: debonding the dried sheet at a predetermined temperature. In one aspect that can be combined with any other aspect or embodiment, the predetermined temperature is in the range of 175°C to 350°C. In one aspect that can be combined with any other aspect or embodiment, the debonding step and the sintering step are performed simultaneously. In one aspect that can be combined with any other aspect or embodiment, the method further includes: pyrolyzing the organic matter in the dried sheet at a temperature in the range of 175°C to 350°C.

[0013] In one aspect that can be combined with any other aspect or embodiment, sintering is performed for a time in the range of less than 45 min and includes continuously feeding the unprocessed strip through the sintering chamber at a predetermined rate measured in in / min. In one aspect that can be combined with any other aspect or embodiment, the final thickness of the sintered composition is in the range of 2 μm to 100 μm directly after sintering without further processing. In one aspect that can be combined with any other aspect or embodiment, the method further includes: continuously forming the sintered composition into a strip.

[0014] In some embodiments, the energy device includes: a first sintered, unpolished electrode having a first surface and a second surface; a first current collector disposed on the first surface of the first electrode; an electrolyte layer disposed on the second surface of the first electrode; a second electrode disposed on the electrolyte layer; and a second current collector disposed on the second electrode. In one aspect that can be combined with any other aspect or embodiment, the first electrode includes the sintered composition described herein. In one aspect that can be combined with any other aspect or embodiment, the electrolyte layer has at least 10 -6 Electrical conductivity in S / cm. In one aspect that can be combined with any other aspect or embodiment, the first electrode is the substrate of the energy device.

[0015] Aspect 1. A method for forming a sintered composition, comprising:

[0016] Provide slurry precursors containing lithium, sodium, or magnesium-based compounds;

[0017] The slurry precursor is strip-formed to form an unprocessed strip; and

[0018] At temperatures ranging from 500°C to 1350°C, sintering of unprocessed strips takes less than 60 minutes to form the sintered composition.

[0019] The slurry precursor further includes solvents and dispersants.

[0020] Aspect 2. The method of Aspect 1, wherein the dispersant includes an amine compound, a carboxylic acid compound, or a combination thereof, a mixture thereof, or a salt.

[0021] Aspect 3. The method of aspect 2, wherein the amine compound includes oleylamine, dibutylamine, or a combination thereof.

[0022] Aspect 4. The method of any one of Aspects 2-3, wherein the amine compound comprises at least one amino group, at least one imine group, or a combination thereof.

[0023] At least one amino group or at least one imine group contains an alkyl chain or an aromatic ring, and

[0024] Amine compounds have fewer than 30 carbon atoms.

[0025] Aspect 5. The method of any one of Aspects 2-4, wherein the carboxylic acid compound includes oleic acid.

[0026] Aspect 6. The method of any one of Aspects 2-5, wherein the carboxylic acid compound comprises an R-COOH structure molecule, wherein R is an alkyl chain or an aromatic ring, and wherein the R-COOH structure molecule has fewer than 30 carbon atoms.

[0027] Aspect 7. The method of any one of Aspects 2-6, wherein the dispersant comprises a combination, mixture, or salt of an amine compound and a carboxylic acid compound.

[0028] The ratio of carboxylic acid compounds to amine compounds is 0:1 to 1:0.

[0029] Aspect 8. The method of aspect 7, wherein the ratio of carboxylic acid compound to amine compound is 1:3 to 3:1.

[0030] Aspect 9. The method of aspect 7, wherein the ratio of the carboxylic acid compound to the amine compound is at least 1:4.

[0031] Aspect 10. The method of any one of Aspects 1-9, wherein the lithium, sodium, or magnesium-based compound has a D50 particle size of up to 0.6 μm.

[0032] Aspect 11. The method of any one of Aspects 1-11, wherein the solvent comprises 1-methoxy-2-propanyl acetate (MPA), isopropanol (IPA), ethyl isobutyrate (EIB), ketones, aromatic hydrocarbons, amines, nitrated hydrocarbons, chlorinated hydrocarbons, or combinations thereof.

[0033] Aspect 12. The method of any one of Aspects 1-11, wherein the solvent is nonpolar and has a dielectric constant of less than 20 at 20 °C.

[0034] Aspect 13. The method of any one of Aspects 1-12, wherein the lithium-based compound comprises at least one of the following: lithium cobaltite (LCO), lithium manganite spinel (LMO), lithium nickel cobalt aluminate (NCA), lithium nickel manganese cobalt oxide (NMC), lithium iron phosphate (LFP), lithium cobalt phosphate (LCP), lithium titanate, lithium niobium tungstate, lithium titanium sulfide, or combinations thereof.

[0035] Aspect 14. The method of any one of Aspects 1-13, wherein a compound based on lithium, sodium, or magnesium is at least 50 wt. of the total slurry precursor.

[0036] Aspect 15. The method of any one of Aspects 1-14, wherein the sodium- or magnesium-based compound comprises at least one of the following: NaVPO4F, NaMnO2, Na 2 / 3 Mn 1-y Mg y O2(0 <y<1)、Na2Li2Ti5O 12 Na2Ti3O7, MgCr2O4, or MgMn2O4.

[0037] Aspect 16. The method of any one of Aspects 1-15, wherein the slurry precursor further comprises at least one of a binder and a plasticizer.

[0038] Aspect 17. The method of aspect 16, wherein strip forming includes:

[0039] The slurry precursor is formed into a sheet configuration with a thickness ranging from 5 μm to 100 μm; and

[0040] The sheet configuration is dried such that the combination of at least one solvent, dispersant, and plasticizer does not exceed 10 wt. of the dried sheet.

[0041] Aspect 18. The method of aspect 17 further includes debonding the dried sheet at a predetermined temperature.

[0042] Aspect 19. The method of aspect 18, wherein the predetermined temperature is in the range of 175°C to 350°C.

[0043] Aspect 20. The method of aspect 18, wherein the debonding step and the sintering step are performed simultaneously.

[0044] Aspect 21. The method of aspect 17 further includes pyrolyzing the organic matter in the dried sheet at a temperature in the range of 175°C to 350°C.

[0045] Aspect 22. The method of any one of Aspects 1-21, wherein sintering is carried out for a time in the range of less than 45 min and includes continuously feeding an unprocessed strip through a sintering chamber at a predetermined rate measured in in / min.

[0046] Aspect 23. The method of any one of Aspects 1-22, wherein:

[0047] Without further processing, the final thickness of the sintered composition is in the range of 2 μm to 100 μm directly after sintering.

[0048] Aspect 24. The method of aspect 1 further includes continuously forming a thin strip of sintered composition.

[0049] Aspect 25. An energy device comprising:

[0050] A first sintered, unpolished electrode, the electrode having a first surface and a second surface;

[0051] A first current collector disposed on the first surface of the first electrode;

[0052] An electrolyte layer disposed on the second surface of the first electrode;

[0053] The second electrode is placed on the electrolyte layer; and

[0054] The second current collector is mounted on the second electrode.

[0055] Aspect 26. Energy device of aspect 25, wherein the first electrode comprises a sintered composition of any one of aspects 1-24.

[0056] Aspect 27. An energy device of any one of Aspects 25-26, wherein the electrolyte layer has at least 10 -6 Conductivity in S / cm.

[0057] Aspect 28. An energy device of any one of Aspects 25-27, wherein the first electrode is a substrate of the energy device.

[0058] Additional features and advantages are set forth in the following embodiments and will be apparent in part to those skilled in the art from the description or to be recognized by practicing the embodiments as described in the written description and its claims, and the accompanying drawings.

[0059] It should be understood that the foregoing general description and the following detailed description are merely exemplary and intended to provide an overview or framework for understanding the nature and characteristics of the claims. Attached Figure Description

[0060] The accompanying drawings are included to provide further understanding and are incorporated in and form a part of this specification. The drawings illustrate one or more embodiments and, together with the specification, serve to explain the principles and operation of the various embodiments.

[0061] Figure 1 A lithium-ion battery described herein is shown according to some embodiments.

[0062] Figure 2 A schematic cross-section of a conventional solid-state, thin-film microcell is shown according to some embodiments.

[0063] Figure 3 The particle size distribution of LCO powder after wear grinding in ceramic ribbon formation is shown according to some embodiments.

[0064] Figure 4 This illustrates a temperature profile in a rapid sintering apparatus, starting from the point of entry into the binder burnout zone, according to some embodiments.

[0065] Figure 5 An example of a dispersant in an LCO slurry formulation for strip forming according to some embodiments is shown: amines (oleylamine), carboxylic acids (oleic acid), and combinations thereof.

[0066] Figure 6A and 6B The diagram shows the particle size distribution curves of LCO dispersed in MPA solvent using fish oil (FO), oleylamine (OAM), oleic acid (OA), and combinations of OA and OAM, according to some embodiments. Figure 6A ) and D10 / D50 / D90 particle size.

[0067] Figure 7A and 7B The diagram shows the particle size distribution curves of LCO dispersed in MPA solvents containing fish oil (FO), dibutylamine (DBA), oleic acid (OA), and combinations of OA and DBA, according to some embodiments. Figure 7A ) and D10 / D50 / D90 particle size.

[0068] Figure 8A and 8B The diagram shows particle size distribution curves of LCO dispersed in IPA solvents using fish oil (FO), oleylamine (OAM), oleic acid (OA), and combinations of OA and OAM, according to some embodiments. Figure 8A ) and D10 / D50 / D90 particle size.

[0069] Figure 9A and 9B The diagram shows the particle size distribution curves of LCO dispersed in IPA solvents containing fish oil (FO), dibutylamine (DBA), oleic acid (OA), and combinations of OA and DBA, according to some embodiments. Figure 9A ) and D10 / D50 / D90 particle size.

[0070] Figure 10A and 10B The figures shown in Table 2 are prepared using MPA as a solvent and formed on Mylar films according to some embodiments. Figure 10A ) and Table 3 ( Figure 10B Images of the moisture-resistant composition of the slurry.

[0071] Figure 11A and 11B This illustrates, according to some implementation methods, in order to obtain data from Table 2 (… Figure 11A ) and Table 3 ( Figure 11B The powder composition was formed on Mylar film, and the improved anti-wetting effect was achieved by using ethyl isobutyrate (EIB) as a solvent instead of MPA.

[0072] Figure 12A and 12B This illustrates, according to some implementation methods, in order to obtain data from Table 2 (… Figure 12A ) and Table 3 ( Figure 12B The slurry composition was formed on a Mylar film, and the image shows the slurry composition prepared using IPA as a solvent.

[0073] Figure 13 The following illustrates the pyrogravimetric analysis (TGA) of various LCO unprocessed strips and powders according to some embodiments.

[0074] Figures 14A-14C This image shows an LCO raw strip prepared using a slurry composition containing EIB solvent and OAM dispersant, according to some embodiments. Figure 14A When the LCO raw strip is drawn into the tube furnace at a speed of 2.3 in / min, the residue of the LCO raw strip ignited during the binder burnout (BBO) process ( Figure 14B); and the successfully sintered LCO strip, which was drawn into a tube furnace at a speed of 1.6 in / min and sintered at 1050°C. Figure 14C ).

[0075] Figure 15A and 15B This diagram shows a scanning electron microscopy (SEM) cross-section of an LCO ribbon sintered at 1050°C, according to some embodiments. Figure 15A ) and top view ( Figure 15B )image. Detailed Implementation

[0076] Referring now to the exemplary embodiments shown in the accompanying drawings. Wherever possible, the same reference numerals will be used throughout the drawings to refer to the same or similar parts. Components in the drawings are not necessarily drawn to scale; rather, the focus is on illustrating the principles of the exemplary embodiments. It should be understood that this application is not limited to the details or methods set forth in the specification or shown in the drawings. It should also be understood that the terminology is used for descriptive purposes only and should not be considered limiting.

[0077] Furthermore, any examples set forth in this specification are illustrative and not restrictive, and merely illustrate some of the many possible embodiments of the claimed invention. Other suitable modifications and adaptations to various conditions and parameters commonly encountered in this art and obvious to those skilled in the art are permitted within the spirit and scope of this disclosure.

[0078] Recently, there has been increased activity focused on understanding how to improve battery energy density to, for example, reduce the time interval between charging sessions, free up space in devices for other functions, and reduce weight where mobility is critical. Furthermore, higher energy density generally reduces costs because less material is consumed in the manufacturing process. Much of this attention has been focused on lithium-ion batteries, and efforts can be broadly categorized into two types.

[0079] In one approach, largely compatible with existing lithium-ion battery manufacturing technologies, advanced cathode materials with higher capacities, such as NMC 811 and NCA (used alone or in combination with surface coatings), are being developed, or increasing amounts of silicon can be added to the battery anode. In a second approach, the technology aims to achieve a lithium metal anode. This approach involves solid electrolytes such as lithium garnet, lithium phosphosilicate, and LiPON.

[0080] This disclosure relates to the design of a novel formulation for the continuous forming and sintering of LCO strips. Dispersants, binders, plasticizers, and solvents are the four key components of the slurry formulation, excluding the solid powder. Dispersants affect the strip forming process and the quality of the unprocessed strip. Binders and plasticizers affect the strip's strength, flexibility, release properties, and ability to assemble from strip stacks by extrusion. Solvents affect the drying rate and coilability of the unprocessed strip during continuous forming.

[0081] Specifically, this application discloses novel dispersants in LCO ribbon slurry formulations that promote better dispersion of LCO powder. Dispersants play a crucial role in ribbon forming because they are essential for dispersion, wetting, high density, porosity, deflocculation, slurry stability, and the strength of the unprocessed ribbon. They also serve as a starting point for ribbon forming using fine powders. After solvent evaporation, the dispersant allows particles to settle into a tightly compacted unprocessed ribbon. Therefore, an effective dispersant can increase the density and strength of the unprocessed ribbon.

[0082] The dispersants disclosed herein include amine molecules or combinations of amines and carboxylic acids. Amines or combinations of amines and carboxylic acids used as dispersants improve LCO dispersion to obtain stable slurries for ribbon forming. In some embodiments, the amine compound may include at least one amino group and / or imine group containing an alkyl chain or aromatic ring, wherein the number of carbons in the structure is less than 30. In some embodiments, the carboxylic acid compound may include an R-COOH molecule, wherein R is an alkyl chain or aromatic ring and the number of carbons in the structure is less than 30.

[0083] Figure 5An example of a dispersant in an LCO slurry formulation for tape forming, according to some embodiments, is shown: an amine (oleylamine), a carboxylic acid (oleic acid), and combinations thereof. The combination of amine (oleylamine) and carboxylic acid (oleic acid) does not form a compound with a specific molecular morphology. In other words, the combination can be a mixture or a salt, depending on the acid-to-amine ratio and its interaction with other components in the slurry. The choice of combination ratio, chain length, and the structure of the organic acid and amine depends on other slurry components, such as solvents and binders, because the behavior of the surfactant (i.e., dispersant) depends on the hydrophilic-lipophilic balance (HLB) value, the interactions between the components, and the pH preference of the binder. HLB is a measure of the degree to which a compound is hydrophilic or lipophilic, determined by calculating the HLB values ​​of different regions of the molecule used in the application. Good dispersants / surfactants have HLB values ​​compatible with solvents and / or binders. Shorter alkyl chains exhibit weak hydrophobic interactions. Regarding pH preference, some powders or binders function well in slightly acidic conditions, while others function better in alkaline conditions. Because amines are basic molecules and carboxylic acids are acidic molecules, the amine:carboxyl ratio can be varied to provide a suitable pH environment for the powders and binders.

[0084] Other dispersants for the ribbon forming of ceramic powders may include fatty acids, esters, phosphate esters, and terpineol. Other dispersants for the ribbon forming of ceramic powders may include polymers such as polyethylene glycol (PEG), polyvinyl butyral (PVB), and polyvinyl pyrrolidone (PVP).

[0085] Binders and plasticizers provide crosslinking and improve the tensile strength of the unprocessed ceramic matrix. As mentioned above, the properties of the dispersant (e.g., composition ratio, chain length, and structure of organic acids and amines) depend on the appropriate selection of the binder. Binders that work well with the dispersants disclosed herein include polyvinyl butyral (PVB), polyacrylic acid, and polypropylene carbonate, such as QPAC 25 and QPAC 40. These binders may include hydroxyl or carbonyl functional groups, which provide sites for attaching the dispersant. The dispersants disclosed herein are organic molecules, and therefore have less steric hindrance and better controllable orientation compared to commercial polymeric dispersants used to interact with binders. The interaction between the binder and dispersant disclosed herein helps prevent the formation of entangled networks and bridging flocculation at the overhanging ends of the binder, which can lead to gravitational settling of ceramic particle clusters, increased slurry viscosity, and molded parts with uneven particle distribution.

[0086] Plasticizers that work well with the dispersants disclosed herein include dibutyl phthalate, the non-phthalate plasticizer Santicizer® Platinum P-1400, polyols, acetates, glycerides, castor oil, and mineral oils. As described above regarding binders, these plasticizers have hydroxyl or carbonyl functional groups, which provide sites for interaction with the dispersant and form a uniform and stable paste for molding.

[0087] The choice of solvent depends on the desired properties of the carrier film (i.e., the film formed by shaping the slurry composition) and the required vapor pressure for the drying rate. Solvents may include propylene oxide-based ethylene glycol ether acetates, esters, alcohols, and hydrocarbons. In some embodiments, solvents include 1-methoxy-2-propanylacetate (MPA), isopropanol (IPA), ethyl isobutyrate (EIB), ketones, aromatic hydrocarbons, amines, nitrated hydrocarbons, chlorinated hydrocarbons, or combinations thereof.

[0088] As described above, this disclosure relates to a novel formulation design for the continuous forming and sintering of LCO strips for electrodes in LIB applications.

[0089] Sintered cathodes achieve higher energy densities by making more efficient use of available space. For example, sintered cathodes increase energy density by serving as mechanical supports. Typically, aluminum supports are used as mechanical supports for battery structures. A thickness of only about 0.5 μm to 1.0 μm is sufficient for current distribution and collection. It is typically applied to one side of the cathode support via metal evaporation or other industrial thin-film deposition processes. For porous structures of solid-state batteries, the energy density of sintered cathodes of LCOs disclosed herein (i.e., without the need for aluminum supports) is increased by about 50% by volume and about 27% by weight, and for dense structures, it is increased by about 80% by volume and about 37% by weight. When compared with conventionally prepared cathodes, sintered cathodes eliminate the mass and volume of organic binders and conductive carbon.

[0090] Referring generally to the accompanying drawings, various embodiments of sintered electrodes comprising at least one alkali metal or alkaline earth metal are disclosed. The sintered electrodes have a thickness of 2 μm to 150 μm and a cross-section of at least 3 cm. 2The cross-sectional area of ​​the electrode is [not specified]. Compared to conventional electrode materials, sintered electrodes can be manufactured to be much larger and self-supporting than typical thin-film formed electrodes, and can be used without any additional finishing techniques such as grinding or polishing, unlike other sintered electrodes. The disclosed sintered electrode achieves these advantages through a strip-forming process that allows for faster manufacturing speeds of "medium" thickness electrode materials, where the processing speed is independent of the electrode thickness. That is, the electrode can be manufactured to be thicker than conventional electrodes manufactured using thin-film technology, and thinner than other sintered electrodes that must be ground to a usable size. Furthermore, the electrode can be sintered quickly in a more economical process compared to current processes used to manufacture electrode materials. In practice, conventional processes typically use thin-film technologies, which are slower and more difficult to build thick layers. In this way, the relatively thick sintered electrode of this disclosure not only eliminates non-functional components, such as mechanical supports, but also increases the battery's charge capacity. In addition, the electrode thickness and the strip-forming manufacturing process allow for the manufacture of electrode materials in roll-to-roll form.

[0091] The sintered electrodes disclosed herein are intended to be applicable to various battery chemistry compositions, including lithium-ion, sodium-ion, and magnesium-ion batteries, as well as batteries using solid-state or liquid electrolytes. This document discloses various embodiments of the sintered electrodes, manufacturing processes, and lithium-ion batteries. These embodiments are provided by way of example and not by way of limitation.

[0092] As mentioned, various embodiments of the sintered electrode include at least one of alkali metals or alkaline earth metals. In other embodiments, the sintered electrode may be a fluoride compound. In embodiments, the sintered electrode includes at least one of lithium, sodium, or magnesium. In embodiments, the sintered electrode also includes at least one transition metal such as cobalt, manganese, nickel, niobium, tantalum, vanadium, titanium, copper, chromium, tungsten, molybdenum, tin, germanium, antimony, bismuth, or iron.

[0093] Exemplary embodiments of lithium-based electrodes include, in particular, lithium cobaltite (LCO), lithium manganite spinel (LMO), lithium nickel cobalt aluminate (NCA), lithium nickel manganese cobalt oxide (NMC), lithium iron phosphate (LFP), lithium cobalt phosphate (LCP), lithium titanate, lithium niobium tungstate, lithium nickel manganese oxide, and lithium titanium sulfide (LiTiS2). Exemplary embodiments of sodium-based electrodes include, in particular, NaVPO4F, NaMnO2, and Na... 2 / 3 Mn 1-y Mgy O2(0 <y<1)、Na2Li2Ti5O 12 Or Na2Ti3O7. Exemplary embodiments based on magnesium include, in particular, magnesia-chromite (MgCr2O4) and MgMn2O4.

[0094] In embodiments, the sintered electrode includes a first phase and at least one other phase mixed with the first phase (e.g., a second phase, a third phase, a fourth phase, etc.). In embodiments, one or more additional phases are selected to provide additional functionality. For example, in one embodiment involving a lithium electrode, a second phase, such as a lithium garnet phase, enhances the effective lithium conductivity of the electrode. In one embodiment, the second phase enhances electronic conductivity. The additional one or more phases may be added prior to sintering, or the sintered electrode may contain open pores that can be wetted with the additional one or more phases. In one embodiment, the second phase is spinel, which provides additional electronic conductivity.

[0095] Increased electronic conductivity is beneficial for the manufacturing process of single-cell batteries. For example, increased conductivity reduces the battery's internal resistance, enabling faster charging and higher power delivery. Increased conductivity also allows for the use of thicker electrodes, which is beneficial for cathode manufacturing and battery assembly. Battery capacity is controlled by the quality of the active electrode materials. In contrast, the rate of the sheet manufacturing process is determined by area. In other words, regardless of the sheet thickness, the same area can be produced. Therefore, if the cathode is thicker, a cathode of a given capacity can be manufactured in a shorter time. Using a thinner cathode to improve rate performance means assembling more layers of single cells to build a battery of a given capacity. The number of assembly steps required to manufacture a battery with a thicker cathode can be reduced, thereby lowering costs.

[0096] In some embodiments, the sintered electrode includes a first phase and trace amounts of a second phase.

[0097] One advantage of the sintered electrodes disclosed herein is that they can be manufactured larger than conventional electrode materials used in batteries, such as those used in thin-film technology. In embodiments, the sintered electrodes have a thickness of 2 μm to 150 μm, or 5 μm to 150 μm, or 20 μm to 80 μm, or 30 μm to 60 μm, or any value or subrange thereof disclosed. In addition to being thicker than thin-film electrodes, sintered electrodes can also be fabricated to have a relatively large cross-sectional area. In embodiments, the sintered electrode has a thickness of at least 3 cm². 2 or at least 10 cm 2 or at least 100 cm 2 or up to 1 m 2 The cross-sectional area, or any value or subrange thereof disclosed therein.

[0098] Sintered electrodes can be manufactured to be larger than conventional thin-film electrodes because they are formed from rapidly sintered strips or extruded raw strips. To form the raw strip, a slurry (or paste) is prepared from powder components, a binder, and a solvent. The powder components include one or more powdered compounds containing lithium, sodium, or magnesium-based compounds and at least one alkali metal or alkaline earth metal. The powdered compound containing lithium, sodium, or magnesium-based compounds and alkali metals or alkaline earth metals can be a single powdered compound. Alternatively or additionally, the compound may include a lithium, sodium, or magnesium-based compound and a single compound containing an alkali metal or alkaline earth metal. Furthermore, in embodiments, the powdered compound may further contain a transition metal, either together with the lithium, sodium, or magnesium-based compound and the compound containing an alkali metal or alkaline earth metal, or in a single compound.

[0099] For example, with respect to lithium electrodes, the powdered compound may include lithium and transition metals such as LCO or LMO. In another example, a compound may contain a lithium compound and a compound containing an alkali metal or alkaline earth metal, and another compound may contain a transition metal. For example, with respect to lithium electrodes, the lithium compound may be, in particular, at least one of the following: Li₂O, Li₂CO₃, LiOH, LiNO₃, lithium acetate (CH₃COOLi), or lithium citrate (Li₃C₆H₅O₇), and the compound containing a transition metal may be at least one of the following: MnO₂, Mn₂O₃, Co₂O₃, CoO, NiO, Ni₂O₃, Fe₂O₃, Fe₃O₄, FeO, TiO₂, Nb₂O₅, V₂O₅, VO₂, Ta₂O₅, or WO₃. In embodiments, the powder component of the slurry or paste (comprising all powdered compounds) accounts for 40% to 75% by weight of the slurry (or paste). In other embodiments, the powder component accounts for 45% to 60% of the slurry (or paste) by weight, and in other embodiments, the powder component accounts for 50% to 55% of the slurry (or paste) by weight.

[0100] The slurry (or paste) has a binder that holds the powder components together in the form of an unprocessed ribbon before sintering. In embodiments, the binder is particularly at least one of the following: polyvinylbutyral (PVB) (e.g., Butvar® PVB resin available from Eastman Chemical Company), acrylic polymers (e.g., Elvacite® acrylic resin available from Lucite International; polyacrylic acid, etc.), and polyvinyl alcohol.

[0101] The slurry (or paste) also has a solvent in which powder components and binders are dispersed. The choice of solvent depends on the desired properties of the carrier film (i.e., the film formed by shaping the slurry composition) and the required vapor pressure for the drying rate.

[0102] Solvents can also be selected to prevent the leaching of alkali or alkaline earth metals from lithium, sodium, or magnesium-based compounds in the slurry. This leaching can occur due to ion exchange or hydroxide formation. Once alkali or alkaline earth metals enter the solvent, several undesirable side effects can occur. For example, the solubility of the binder may decrease; the dissolved metal may interfere with the dispersant; the dissolved metal may migrate during drying, leading to chemical inhomogeneity in the dried ribbon; or the chemical properties of the inorganic particles themselves may change. Furthermore, the reaction with the solvent is time-dependent, thus the slurry properties are subject to continuous changes and potentially unstable processes.

[0103] Solvents may include propylene oxide-based glycol ether acetates, esters, alcohols, hydrocarbons, 1-methoxy-2-propanyl acetate (MPA), ethanol-butanol mixtures, or combinations thereof. In some embodiments, solvents include 1-methoxy-2-propanyl acetate (MPA), isopropanol (IPA), ethyl isobutyrate (EIB), ketones, aromatic hydrocarbons, amines, nitrated hydrocarbons, or chlorinated hydrocarbons, or combinations thereof.

[0104] Therefore, in this embodiment, the solvent is selected to be nonpolar. In a specific embodiment, the nonpolar solvent has a dielectric constant of less than 20 at 20°C. In other embodiments, the nonpolar solvent has a dielectric constant of less than 10 at 20°C, and in other embodiments, the nonpolar solvent has a dielectric constant of less than 5 at 20°C. Furthermore, in this embodiment, the solvent leaches less than 1 ng / L of alkali metal or alkaline earth metal from the powder component in the slurry. In other embodiments, the solvent leaches less than 0.1 ng / L of alkali metal or alkaline earth metal from the powder component in the slurry, and in other embodiments, the solvent leaches less than 0.01 ng / L of alkali metal or alkaline earth metal from the powder component in the slurry.

[0105] In some implementations, the chemical properties of the binder can be modified to work in conjunction with nonpolar solvents such as MPA. For example, Butvar® B-79 is a commercially available PVB with a low concentration of hydroxyl groups derived from polyvinyl alcohol (11-13% by weight) and a low molecular weight compared to other PVB binders. This allows for easy dissolution and high solubility to control viscosity and achieve high solids loading.

[0106] In embodiments, the slurry (or paste) may contain other additives that facilitate processing. For example, in embodiments, the slurry (or paste) may contain between 0.1% by weight and 5% by weight of dispersant and / or plasticizer. Regarding the dispersants described above, novel dispersants for LCO ribbon slurry formulations are disclosed, which promote better dispersion of LCO powder. Dispersants in ribbon forming are crucial for dispersion, wetting, high density, porosity, deflocculation, slurry stability, and the strength of the unprocessed ribbon. After solvent evaporation, the dispersant allows particles to settle into a tightly compacted unprocessed ribbon. Therefore, an effective dispersant can increase the density and strength of the unprocessed ribbon.

[0107] The dispersants disclosed herein include amine molecules or combinations of amines and carboxylic acids. Amines or combinations of amines and carboxylic acids, as provided above, modify LCO dispersions to obtain stable slurries for ribbon forming. In some embodiments, the amine compound may include at least one amino group and / or imine group containing an alkyl chain or aromatic ring, wherein the number of carbons in the structure is less than 30. In some embodiments, the carboxylic acid compound may include an R-COOH molecule, wherein R is an alkyl chain or aromatic ring and the number of carbons in the structure is less than 30. Amines or combinations of amines and carboxylic acids, as dispersants, modify LCO dispersions to obtain stable slurries for ribbon forming. Other dispersants for ribbon forming of ceramic powders may include fatty acids, esters, phosphate esters, terpineol, and fish oil. Other dispersants for ribbon forming of ceramic powders may include polymers such as polyethylene glycol (PEG), polyvinyl butyral (PVB), and polyvinyl pyrrolidone (PVP).

[0108] Plasticizers that work well with the dispersants disclosed herein include dibutyl phthalate and non-phthalate plasticizers such as Santicizer® Platinum P-1400, polyols, acetates, glycerides, castor oil, and mineral oil.

[0109] Furthermore, as will be discussed more fully below, the presence of transition metal oxides in the slurry (or paste) can induce catalytic combustion reactions during sintering. Therefore, in embodiments, the slurry (or paste) may contain additives to prevent or reduce the severity of such combustion reactions. Specifically, the slurry (or paste) may contain antioxidants such as phenol (e.g., butylated hydroxytoluene (BHT) or alkylated diphenylamine), or materials with endothermic decomposition properties, such as inorganic carbonates and hydroxides.

[0110] deal with

[0111] The slurry (or paste) is strip-formed or extruded to obtain an unprocessed strip of the desired thickness for sintering electrodes. As discussed above, the thickness can range from 2 μm to 150 μm. In one embodiment, the unprocessed strip is dried to remove a substantial portion of the solvent, leaving primarily lithium, sodium, or magnesium-based compounds containing alkali metals or alkaline earth metals. In another embodiment, drying can occur at ambient temperature or at a slightly elevated temperature of 60°C to 80°C (or begin at ambient temperature and transition to an elevated temperature). Furthermore, in another embodiment, air is circulated to enhance drying. In another embodiment, the amount of organic material remaining after drying does not exceed 10% by weight of the dried unprocessed strip. After drying, the unprocessed strip is debonded and sintered. That is, the unprocessed strip is heated to a temperature at which the polymer binder and any other organic matter are burned off. In another embodiment, debonding occurs in a temperature range of 175°C to 350°C. Subsequently, the dried and debonded unprocessed strip is sintered. Sintering occurs in a temperature range of 500°C to 1350°C. The sintering time within this temperature range is less than 60 minutes. In one embodiment, the sintering time is less than 50 minutes, and in other embodiments, the sintering time is less than 45 minutes. After sintering, the porosity of the sintered electrode does not exceed 30%. In one embodiment, the sintered electrode strip has a porosity of not more than 25%. In other embodiments, the sintered electrode has a porosity of not more than 20%, and in other embodiments, the sintered electrode has a porosity of not more than 15%. In one embodiment, the porosity of the sintered electrode is at least 0.1%. Due to the sintering process, in one embodiment, the sintered electrode has an average particle size of 10 nm to 50 μm. In other embodiments, the average particle size is 50 nm to 10 μm, and in other embodiments, the average particle size is 100 nm to 1000 nm.

[0112] Furthermore, in the embodiments, the sintered electrode has open porosity, thereby providing fluid communication between the first and second surfaces of the sintered electrode. That is, in the embodiments, a lithium, sodium, or magnesium-based compound phase constitutes the solid phase, and the pores constitute a second phase, wherein the second phase is a continuous phase within the solid phase. Furthermore, in the embodiments, the pores of the sintered electrode tape are substantially aligned to facilitate ion transport. That is, the pores are aligned along an axis perpendicular to the first and second surfaces. For example, each pore may have a cross-sectional dimension longer than any other cross-sectional dimension of that pore, and the longer cross-sectional dimension is substantially perpendicular to the first and second surfaces of the electrode, for example, aligned on average within 25° of the vertical line. Advantageously, compared to other sintered electrodes, the described sintering process produces sintered electrodes that do not require further finishing (e.g., mechanical grinding or polishing) before being incorporated into the battery structure. Specifically, previously sintered electrodes were formed from larger disks with thicknesses, for example, 500 μm to 1 mm, and had to be cut to usable dimensions and ground to usable thickness. It has been reported that this grinding process can only achieve a thickness of about 130 μm, which is the practical limit for electrodes manufactured using such processes. By forming the electrodes into thin strips, not only is the process more economical (e.g., eliminating the need for grinding / polishing steps and enabling roll-to-roll manufacturing), but the desired electrode material thickness can also be achieved.

[0113] Furthermore, because the sintered electrode is self-supporting, it can be used as a substrate for depositing additional layers. For example, a metal layer (e.g., up to 5 μm) can be deposited on the surface of the sintered electrode to serve as a current collector for the battery. Additionally, in exemplary embodiments, solid electrolytes such as lithium phosphorus oxynitride (LiPON) and lithium garnet (e.g., garnet LLZO (Li7La3Zr2O)) are used. 12 Lithium sulfide-phosphorus (LiPO4) solid electrolytes can be deposited onto sintered electrodes via RF sputtering. Alternatively, thin-layer LiPON solid electrolytes can be applied via ammonolysis of thin-layer Li3PO4 or LiPO3, or via reactive sintering. These processes are envisioned to be faster and potentially less capital-intensive compared to conventional solid electrolyte deposition techniques. Similarly, solid electrolytes of lithium garnet (e.g., LLZO) can be applied via sol-gel, direct sintering, and reactive sintering.

[0114] Furthermore, as a self-supporting layer, sintered electrodes can provide a basis for advantageous manufacturing methods of lithium-ion batteries using liquid electrolytes. In other words, the cathode (i.e., the sintered electrode) serves as the substrate of the battery. Specifically, sintered electrodes can be manufactured in a continuous process and used as a substrate for coating in batch or roll-to-roll processing. This process allows the sintered electrode to be metallized, for example, by sputtering and / or electrolytic deposition, to form a metallized sintered electrode. In this way, the thickness of the electrode current collector metal in conventional lithium-ion batteries can be reduced from a typical thickness of 10-15 μm to at least 5 μm, less than 1 μm, or even less than 100 nm. Moreover, the metallized sintered electrode can be supplied to battery cell manufacturers as a separate component in sheet or roll form. Advantageously, such metallized sintered electrodes reduce the volume of the cell typically reserved for the current collector, thereby allowing for more active electrode material and higher capacity.

[0115] In this respect, sintered electrodes are particularly suitable for ion-intercalation batteries. Exemplary embodiments of the lithium-ion battery 10 are shown in... Figure 1 The lithium-ion battery 10 includes a sintered cathode 12, an electrolyte layer 14 or region, and an anode 16. In one embodiment, the sintered cathode 12 has a thickness of 2 μm to 150 μm. Additionally, in another embodiment, the sintered cathode 12 has a thickness of at least 3 cm. 2 The cross-sectional area of ​​the cathode 12. Advantageously, the sintered cathode 12 mechanically supports the lithium-ion battery 10 so that the sintered cathode 12 is not supported on a mechanical support such as a zirconium oxide support. The advantage of this architecture is that it essentially eliminates non-functional components in the battery. That is, while providing mechanical support, the sintered cathode 12 remains a functional component and contributes to the battery's capacity. Therefore, the cathode support design can provide the same total capacity with a thinner profile, or the cathode thickness can be increased to achieve a higher net capacity within the same dimensions.

[0116] Furthermore, the sintered cathode 12 can be used in both solid-state and liquid electrolyte lithium-ion batteries. Specifically, in a solid-state battery, the electrolyte layer 14 includes a solid electrolyte (e.g., having a >10 ppm). -6 The electrolyte layer 14 comprises a solid electrolyte, such as LiPON, lithium garnet (e.g., LLZO), or lithium sulfophosphorus, with a conductivity of S / cm. More specifically, in a solid-state battery, the electrolyte layer 14 comprises a solid electrolyte, such as LiPON, lithium garnet (e.g., LLZO), lithium sulfophosphorus, or a lithium super ionic conductor (LISICON), and the combination of lithium-ion conductivity and thickness results in a specific areal resistivity of less than about 100 Ωcm. 2Specifically, one advantage of LiPON is its resistance to dendrite crystal growth. In a liquid electrolyte battery, the electrolyte layer 14 comprises a liquid electrolyte, such as LiPF₆-DMC (lithium hexafluorophosphate in dimethyl carbonate), and a polymer or ceramic separator that separates the cathode 12 from the anode 16. In either case, the sintered cathode 12 provides increased charging capacity compared to conventional lithium-ion batteries.

[0117] The battery 10 also includes a first current collector 18 disposed on a first surface of the sintered cathode 12. In the illustrated embodiment, a second current collector 20 is disposed on the anode 16; however, in embodiments, the anode may be a metal (e.g., lithium metal or magnesium metal), in which case the current collector may be omitted. Furthermore, in the illustrated embodiment, the battery 10 is encapsulated in a protective coating 22. In embodiments, the first current collector 18 is copper, and the second current collector 20 (when used) is aluminum. The protective coating 22 may be, for example, parylene.

[0118] Although the depicted embodiment only includes the sintered cathode 12, the anode 16 may also be a sintered electrode according to the present disclosure. For a lithium-ion battery, the (sintered) cathode 12 may comprise at least one of lithium cobalt oxide, lithium manganese spinel, lithium nickel cobalt aluminate, lithium nickel manganese cobalt oxide, lithium iron phosphate, lithium cobalt phosphate, lithium nickel manganese oxide, or lithium titanium sulfide, and the (sintered) anode 16 may comprise at least one of lithium titanate or lithium niobate tungstate.

[0119] Furthermore, although a lithium-ion battery is described, the battery may alternatively be based on sodium-ion, calcium-ion or magnesium-ion chemistries. For a sodium-ion battery, the (sintered) cathode 12 may comprise at least one of NaMnO₂, Na 2 / 3 Mn 1-y Mg y O₂ (0<y<1), or NaVPO₄F, and the (sintered) anode 16 may comprise at least one of Na₂Li₂Ti₅O 12 or Na₂Ti₃O₇. For a magnesium-ion battery, the (sintered) cathode 12 may comprise at least one of MgCr₂O₄ or MgMn₂O₄, and the anode 16 may be magnesium metal (which can also act as the second current collector 20). Any of the aforementioned battery chemistries may use a liquid electrolyte comprising a solvent (e.g., DMC) and a salt having a cation matching the intercalation ion. Additionally, for sodium-ion batteries, sodium super ionic conductor (NASICON) can be used as a solid electrolyte.

[0120] For the purpose of demonstrating the capacity gain, Figure 2A schematic cross-section of a conventional solid-state thin-film microcell 100 is provided. The microcell 100 includes a cathode current collector 102 and an anode current collector 104 deposited on an inert mechanical support 106. A cathode 108 (e.g., LCO or LMO) is formed on the cathode current collector 102 and surrounded by a solid electrolyte 110 (e.g., LiPON). An anode 112 is deposited on the electrolyte 110 and the anode current collector 104. A coating 114 is provided to protect the cathode 108, electrolyte 110, and anode 112. In conventional battery designs, the mechanical support 106 is relied upon for processing during the manufacture of the battery 100, and this support serves as a platform for depositing the cathode 108 and electrolyte 110 layers. The mechanical support 106 typically has a thickness of 50 μm to 100 μm. The mechanical support 106 and the protective coating 114 also provide rigidity to the final package and help prevent damage.

[0121] In these conventional cells 100, the cathode 108 is typically grown to the desired thickness via processes such as RF sputtering or pulsed laser deposition. These deposition techniques are another reason why the conventional cell 100 requires a mechanical support 106. These conventional methods produce cathode material at rates <10 μm / hr, thus imposing practical and commercial limitations on the achievable thickness of these conventional cathode materials. Therefore, thin-film microcells are only used in applications requiring small-size power sources, such as smart cards, medical implants, RFID tags, and wireless sensing.

[0122] According to this public case Figure 1 The charging capacity of the battery 10 and Figure 2 The charging capacity comparison of the conventional battery 100 was performed at a nominal thickness of 80 μm. Specifically, a comparison was made between (1) the conventional battery 100 having a 50 μm thick mechanical support 106 with zirconium oxide and a 5 μm thick cathode, and (2) the battery 10 disclosed in this invention having a 35 μm thick cathode 12. Notably, the thickness of the cathode 12 of the battery 10 disclosed in this invention is less than the thickness of the mechanical support 106 of the conventional battery 100, thereby allowing space to be reserved for metallic lithium at the anode 16. In both absolute and volumetric terms, the additional thickness of the sintered cathode 12 and the removal of the mechanical support 106 provide a capacity seven times higher, and ten times greater by weight.

[0123] Besides simply allowing for a larger electrode, the sintered cathode 12 of the depicted embodiment also offers the structural advantage of increased charging capacity compared to conventional cathodes. In a conventional cathode 108, the active cathode particles make point contact. The cross-sectional area of ​​the contact is very small, thus exhibiting high resistance to the movement of lithium ions and electrons. To overcome this resistance problem, carbon is added to the electrode as a conductive pathway to facilitate the transport of electrons in and out of the active particles, and the pore spaces in the electrode are permeated by a liquid electrolyte to rapidly conduct lithium ions. This use of carbon creates a trade-off between battery capacity and charge / charge rate performance. Another problem with the point contact between the active cathode particles is that such contact is weak; therefore, polyvinyl fluoride (PVF) is used to bind the active particles to carbon to provide structural strength during processing. In contrast, the particles in the depicted sintered cathode 12 are bonded together, thus eliminating the need for electron-conducting carbon and binders. In this way, the proportion of space allocated to pores that facilitate lithium ion movement can be reduced, and more space can be dedicated to the active material used with the sintered cathode. The inventors estimate that, for a given cathode material, the total capacity can be increased by approximately 30% at the same cathode thickness. Alternatively, the cathode thickness can be reduced by 20-25% while maintaining the same capacity for a more compact battery. As described above, the pores in the sintered cathode 12 can be aligned in the direction of ion entry and exit from the anode, thereby enabling further improvements in space utilization or increased power density.

[0124] As used herein, the term "self-supporting" refers to a structure that is not adhered to or supported by an underlying substrate (via an inert mechanical support). In some instances, self-supporting sintered electrodes are freestanding, allowing for mechanical manipulation or movement of the electrodes without the need for adhesion or fixation to the substrate, and can themselves serve as a substrate for depositing additional layers. Therefore, in the embodiments described herein, the self-supporting sintered electrode has a dual function: serving as a support on which additional energy storage elements (e.g., electrolyte layers, current collectors, etc.) can be disposed, and as a functional component of the battery (e.g., cathode or anode). As used herein, the term "cross-sectional area" refers to the cathode surface area that can be used to support the battery structure. For example, see reference... Figure 1 The cross-sectional area of ​​the sintered cathode 12 is defined by the horizontal length (e.g., width) of the cathode (measured as the length between the protective coatings 22) and the depth of the cathode (into the page).

[0125] In some instances, the cathode can be completely dense, containing closed or open pores, with an open porosity of up to 30%. Sintered cathodes can have a thickness of 5 to 150 μm. The process of manufacturing a cathode with this conductivity requires, after sintering, a residence time of at least 1 minute and at most 1 hour at a temperature of 400°C to 825°C in an atmosphere of at least 5 vol.% oxygen. This residence time can be provided as a holding time during the cooling process of the high-temperature sintering or as a separate processing step.

[0126] ---------- / / ----------

[0127] This disclosure relates to the design of novel formulations for the continuous forming and sintering of LCO strips. Dispersants, binders, plasticizers, and solvents are four key components in the slurry formulation, excluding solid powder. Specifically, this application discloses novel dispersants in the LCO strip slurry formulation that promote better dispersion of the LCO powder. The dispersants affect the strip forming process and the quality of the unprocessed strip. The binders and plasticizers affect the strip strength, flexibility, release properties, and the ability to assemble from strip stacks by extrusion. The solvents affect the drying rate and rollability of the unprocessed strip during continuous forming.

[0128] Example

[0129] Example 1 - Cathode Preparation and Characterization

[0130] Starting with lithium cobalt oxide purchased from American Elements, a rapidly sintered freestanding cathode was prepared. The powder was nominally stoichiometric, and XRD indicated it was single-phase, with peak positions and intensities consistent with layered rock salt structures. The received powder was ground to break the aggregate into dispersible particles of the desired sintering size. Grinding was performed using a Union Process Mill in batch mode with a 1 L grinding jar. 2600 g of 2 mm diameter zirconia media, 400 g of the received LCO powder, and 360 mL of isopropanol were fed into the mill. The mill was stirred at 2000 rpm for 3 hours. The typical average particle size after grinding was between 0.35 and 0.45 μm, and the particle size distribution (mainly varying between 0.2 μm and 1.1 μm) exhibited the following characteristics: Figure 3 The image shows the particle size distribution of LCO powder after wear grinding during ceramic ribbon formation.

[0131] The powder and media are dried together and then separated by sieving.

[0132] Ceramic ribbons for rapid sintering are formed using milled LCO powder. The total concentration of binder and non-volatile organic compounds is determined to control the ribbon's flammability and ensure it bonds at a reasonable rate during rapid sintering. The slurry composition contains 40-95 wt.% LCO powder, 2-40 wt.% binder, 1-5 wt.% dispersant, and 1-20 wt.% plasticizer, blended with the remaining solvent. The LCO is dispersed in the solvent before adding the binder by light milling. The slurry is formed into unprocessed ribbons with thicknesses of 35 μm and 25 μm to achieve firing thicknesses of approximately 25 μm and 20 μm, respectively. In both cases, the width is 100 mm. The carrier used for forming is silicone-coated polyethylene terephthalate to facilitate the release of the LCO from the ribbon.

[0133] Rapid sintering of LCO ribbons to produce cathodes is performed by the following:

[0134] (1) Use scissors to manually cut the unprocessed LCO strip still on the carrier into strips 300-400 mm long and 50-60 mm wide. Manually release the strip from the carrier.

[0135] (2) An approximately 3 m long, 80 μm thick alumina strip is passed through a 1 m long muffle furnace operating at 1050 °C, then through an adjacent binder burnout device consisting of two opposing air bearings, and onto a platform. The binder burnout device is approximately 300 mm long and has multiple heating zones programmed to provide a linear temperature uniformity between 225 °C at the inlet and 325 °C at the outlet, and interfaces with the muffle furnace. The air bearings are carefully aligned beforehand with the alumina “D” in the muffle furnace. The purpose of the “D” is solely to provide a flat surface for the alumina strip or cathode strip.

[0136] (3) The LCO strips are carefully placed onto the alumina strips so that their long axes are centered. The alumina strips with LCO strips are pulled through the binder burnout zone at 63.5 mm / min, then through the muffle furnace for sintering, and finally to the platform at room temperature where the strips are collected. A cathode disk with a diameter of 12.3 mm is laser-cut from the sintered LCO strips.

[0137] Figure 4The temperature profile of the LCO strip in a rapid sintering apparatus is shown from the moment it enters the binder burnout zone. Sintering of the LCO strip is completed within exactly 20 minutes. The LCO strip is automatically released from the carrier and pulled directly through the binder burnout apparatus and through the muffle furnace used for roll-to-roll sintering of the cathode strip. No alumina strip is required for transport in this arrangement. Because the strip is thin and flexible, it twists rather than breaks under large temperature gradients. The process used in this paper imparts the same thermal history to the sintered LCO strip.

[0138] Example 2 - Structure of Dispersants

[0139] Figure 5 An example of a dispersant in an LCO slurry formulation for strip forming is shown: an amine (oleylamine), a carboxylic acid (oleic acid), and combinations thereof. The combination of amine and carboxylic acid does not form a compound with a specific molecular structure. Depending on the acid-to-amine ratio and its interaction with other components in the slurry, this combination can be a mixture or a salt. Therefore, the acid-to-amine ratio and the structures of the acid and amine can be varied to achieve desired slurry properties for strip forming, such as pH, viscosity, settling velocity, etc.

[0140] Example 3 - Dispersants for improving LCO dispersion in solvents

[0141] Typically, Figures 6A-9B illustrate the effect of using oleylamine (OAM) in a solvent such as 1-methoxy-2-propanylacetate (MPA) compared to dispersions using fish oil (FO), oleic acid (OA), and combinations of acids and amines. Figure 6A and 6B ) and dibutylamine (DBA) Figure 7A and 7B The LCO dispersed by amines exhibits a smaller particle size. This indicates that amines are better dispersants for LCO in MPA solvents compared to other dispersants. However, the combination of acid and amine as a dispersant shows a greater number of smaller LCO particles compared to using either a single amine or a single acid in isopropanol (IPA) solvent. Figures 8A-9B The optimal acid to amine ratio (OA:OAM or OA:DBA) is 1:3.

[0142] Table 1 discloses several examples of LCO dispersed in 1-methoxy-2-propanyl acetate (MPA) solvent using various dispersants such as fish oil, oleic acid, oleylamine, and combinations of oleic acid and oleylamine. In experiments 1-12, the MPA solvent (6.102 g) and LCO (3.088 g) were kept constant.

[0143]

[0144] Table 1

[0145] Figure 6A and 6B The particle size distribution curves of LCO dispersed in MPA solvents containing fish oil (FO), oleylamine (OAM), oleic acid (OA), and a combination of OA and OAM are shown. Figure 6A ) and D10 / D50 / D90 particle size. Figure 6A A sharp peak at 0.344 μm is shown from the LCO sample containing OAM dispersant. The highest peak at 0.344 μm represents LCO dispersed by OAM alone (Experiment No. 6), indicating that OAM is a better dispersant for LCO in MPA among all samples. Furthermore, according to... Figure 6B Of all the samples, Experiment 6 showed the smallest D50 particle size for LCO dispersed by OAM alone, at 0.467 μm. The LCO without any dispersant had a larger D50 particle size, at 0.677 μm (Experiment 0). After milling, the original LCO particle size was 344 nm. If the particle size remains around 344 nm with the use of a dispersant, it indicates that the ceramic particles are well dispersed in solution. If the particle size is larger than the original 344 nm (e.g., 750 nm or larger), this indicates the presence of some LCO aggregates / clusters in solution. Because binders or plasticizers cannot penetrate the LCO aggregates / clusters, the uniformity and stability of the slurry composition and the quality of the formed ribbon are uncontrollable.

[0146] Figure 7A and 7B The particle size distribution curves of LCO dispersed in MPA solvents containing fish oil (FO), dibutylamine (DBA), oleic acid (OA), and combinations of OA and DBA are shown. Figure 7A ) and D10 / D50 / D90 particle size. Figure 7A This shows the LCO (dispersed by individual DBA) Figure 7BThe peak of sample number 7 is narrow and located at a position less than 0.500 μm. Figure 7A All other curves in the dataset are wider than the curve for DBA alone, and the peak positions are greater than 0.500 μm. This indicates that the data in this dataset (i.e., Figure 7A and 7B Of all the samples in the study, DBA was the preferred dispersant for LCO in MPA. Figure 7B The D50 particle size of LCO dispersed by DBA alone shows that the LCO with the smallest D50 particle size is 0.574 μm. The LCO without any dispersant has a larger D50 particle size, at 0.729 μm. Figure 7B Sample number 1).

[0147] Figure 8A and 8B The particle size distribution curves of LCO dispersed in IPA solvents containing fish oil (FO), oleylamine (OAM), oleic acid (OA), and a combination of OA and OAM are shown. Figure 8A ) and D10 / D50 / D90 particle size. Figure 8A Multiple curves with similar peak positions less than 0.500 μm are shown. However, LCO (dispersed by a combination of OA and OAM with an OA:OAM ratio of 1:3 in IPA) Figure 8B The narrowest peak in sample number 12 indicates it was the best dispersant in this ensemble study. A narrower LCO particle size distribution peak indicates well-dispersed LCO particles and better homogeneity in solution. Figure 8B The D50 particle size of LCO dispersed by sample number 12 is 0.566 μm, slightly smaller than that dispersed by OAM alone (sample number 7) and other ratios of OA:OAM. The D50 particle size of LCO without any dispersant is larger, at 0.613 μm (sample number 1).

[0148] Figure 9A and 9B The diagram shows the particle size distribution curves of LCO dispersed in IPA solvents containing fish oil (FO), dibutylamine (DBA), oleic acid (OA), and combinations of OA and DBA, according to some embodiments. Figure 9A ) and D10 / D50 / D90 particle size. Figure 9AThe peaks of LCO, although multiple curves show peaks below 0.500 μm, are marked. However, the narrowest peaks are those of LCO dispersed by combinations of OA and DBA at ratios of 1:1 (half) (sample 10) and 1:3 (sample 12). This indicates that these are the optimal dispersants for this ensemble study. Figure 9B The D50 particle size shown is 0.57 μm for LCO dispersed by samples 10 and 12, which is slightly smaller than that dispersed by DBA alone (sample 7).

[0149] Example 4 - Solving the problem of moisture-resistant slurry composition

[0150] The problem of moisture resistance when a film composed of a slurry cracks on a substrate poses a significant limitation on the formation of inorganic films with desirable properties such as good stability, uniformity, and continuity on a substrate after aging or heat treatment, because films on non-wettable surfaces are unstable.

[0151] The slurry compositions in Tables 2 and 3 cause wetting problems on Mylar carrier films, which can be caused by the binder or solvent. Mylar is a polyethylene terephthalate (PET) film, widely used in various applications such as electronics, food packaging, industrial specialties, molding and release, and the graphics market due to its balanced tensile properties, good adhesion, excellent moisture and chemical resistance, and ability to withstand temperatures from -100°F to 300°F. Here, silicone-coated Mylar is used and designed for use as a release film in various molding applications and is relatively inexpensive compared to other carrier films. This wetting problem is solved by changing the solvent. Table 2 shows slurry formulations using OAM as a dispersant and MPA as a solvent. Table 3 shows slurry formulations using a combination of OA and OAM at an OA:OAM ratio of 1:4 as a dispersant and MPA as a solvent.

[0152]

[0153] Table 2

[0154]

[0155] Table 3

[0156] Figure 10A and 10B The images shown in Table 2 are prepared using MPA as a solvent and formed on Mylar films. Figure 10A ) and Table 3 ( Figure 10BImage of the moisture resistance of the slurry composition. Moisture resistance is a problem caused by the cracking of the film of the slurry composition on the substrate, as shown in the attached figure. Combination of OA and OAM ( Figure 10B ) compared to OAM( Figure 10A Slightly better, as the combination forms a larger continuous film area compared to OAM alone. Although the film uniformity produced by the combined slurry on the Mylar carrier film is also better than that produced by OAM slurry alone, there is some degree of residue on the Mylar film from both dried, unprocessed strips after release.

[0157] Figure 11A and 11B This shows how to extract data from Table 2 ( Figure 11A ) and Table 3 ( Figure 11B The slurry composition was formed on Mylar film, and the improved image of anti-wetting was achieved by using ethyl isobutyrate (EIB) as a solvent instead of MPA. After drying under ambient conditions, the new slurry composition formed a uniform, continuous, and smooth film on the Mylar carrier film. The dried film was released from the Mylar substrate without residue. In the slurry formulations from Tables 2 and 3, EIB replaced MPA as the solvent. Except for the solvent substitution, the other components and amounts remained the same as in the slurry compositions in Tables 2 and 3. Unprocessed tapes using OAM as a dispersant ( Figure 11A It releases easily without leaving any residue on the Mylar film. Unprocessed ribbons using a combination of OA and OAM as dispersants ( Figure 11B Upon release, a small amount of light brown residue remained on the Mylar film.

[0158] Figure 12A and 12B This shows how to extract data from Table 2 ( Figure 12A ) and Table 3 ( Figure 12B The image shows a paste composition formed on a Mylar film using IPA as a solvent. After drying under ambient conditions, the new paste composition forms a uniform, continuous, and smooth film on a Mylar substrate. However, some residue remains on the Mylar substrate upon release of the dried film, indicating that the interaction between the paste composition and the substrate is too strong. As shown, there are no wetting issues on Mylar films for any paste made with IPA solvent. However, unprocessed strips made with OAM dispersant (…) Figure 12A After the strip was dried, some cracks were observed. The unprocessed strip was made from a combination of OAM and OA as dispersants. Figure 12B After the thin strip is dried, it does not have cracks.

[0159] Therefore, as Figure 10A-12B As shown, the slurry compositions in Tables 2 and 3 can result in different anti-wetting properties on Mylar carrier films, depending on the solvents used in the molding process.

[0160] Example 5 - Slurry composition for continuous strip forming

[0161] Continuous strip forming enables roll-to-roll or continuous in-line processing to reduce the cost of strip ceramics. The slurry used for continuous strip forming requires a stable slurry for producing uniform strips and a relatively fast drying rate to allow for the winding of the unprocessed strip. Table 4 shows the slurry formulation that allows for continuous forming and enables LCO strips to be successfully wound at room temperature with the airflow without stickiness issues. If the solvent in the formed unprocessed strip is not completely dried during continuous strip forming, the formed unprocessed strip becomes sticky, causing it to adhere to the carrier film after winding and resulting in damage to the unprocessed strip upon release.

[0162]

[0163] Table 4

[0164] Example 6 - Pulp composition and sintering process to prevent ribbon combustion

[0165] Unprocessed ribbons containing organic components burn rapidly in air at approximately 200°C during the sintering process, attributed to the exothermic reaction between oxygen released from LCO and the organic material. Combustion of the unprocessed ribbons can be controlled by adjusting the slurry formulation and the sintering process. Rapid burnout of the organic components during the heating process is problematic because the ribbon turns to ash after vigorous combustion.

[0166] Figure 13 The following diagram illustrates the thermal gravimetric analysis (TGA) of various LCO raw strips and powders according to some embodiments. The TGA analysis was performed using a LECO Corp. TGA701 thermal gravimetric analyzer. Heating was carried out under airflow at a rate of 100°C / hour. The weight loss curves from the TGA analysis show that LCO powder without binder experiences gradual weight loss between 200-400°C. However, LCO raw strips with binder experience rapid weight loss between 180-220°C, indicating that a large amount of organic matter is rapidly combusted, attributed to the binder composition and concentration in this temperature range.

[0167] Figures 14A-14C Images showing LCO raw ribbons prepared using a slurry composition containing EIB solvent and OAM dispersant ( Figure 14A When the LCO raw strip is drawn into the tube furnace at a speed of 2.3 in / min, the residue of the LCO raw strip ignited during the binder burnout (BBO) process ( Figure 14B ); and the successfully sintered LCO strip, which was drawn into a tube furnace at a speed of 1.6 in / min and sintered at 1050°C. Figure 14C In air with a flow rate of 6 SCFM, the BBO process exhibits a linear temperature distribution curve from 225 to 325 °C, as shown below. Figure 4 Demonstration. All three zones of the furnace are set to 1050°C to facilitate strip sintering. Figure 14C The slower pulling speed during the process (1.6 in / min, compared to) Figure 14B The 2.3 in / min rate provides additional time for flameless pyrolysis and evaporation of the organic components from the unprocessed strip. The solvent dries completely during strip forming or below 100°C, thus not affecting the flameless pyrolysis. The dispersant molecules selected in this paper have lower heats of vaporization compared to polymeric dispersants, and these dispersants evaporate below 200°C to limit the thermal runaway of LCO. The strip withstands burnout and sintersulates fairly well at 1050°C.

[0168] Figure 15A and 15B This shows a scanning electron microscopy (SEM) cross-section of an LCO ribbon sintered at 1050 °C. Figure 15A ) and top view ( Figure 15B Image. The raw ribbon was prepared from a slurry composition containing OAM dispersant, Butvar B-79 binder, dibutyl phthalate plasticizer, and EIB solvent. SEM images show that the ribbon has a dense structure. The particle shape appears to have a rice grain top view shape and exhibits fibrous structure when viewed in cross-section.

[0169] Therefore, this disclosure generally relates to the design of novel formulations for the continuous forming and sintering of LCO strips. Dispersants, binders, plasticizers, and solvents are the four key components of the slurry formulation, excluding solid powder. Dispersants affect the strip forming process and the quality of the unprocessed strip. Binders and plasticizers affect the strip's strength, flexibility, releasability, and ability to assemble from strip stacks by extrusion. Solvents affect the drying rate and rollability of the unprocessed strip during continuous forming.

[0170] Specifically, this application discloses novel dispersants in LCO ribbon slurry formulations that promote better dispersion of LCO powder. Dispersants play a crucial role in ribbon forming because they are essential for dispersion, wetting, high density, porosity, deflocculation, slurry stability, and the strength of the unprocessed ribbon. They also serve as a starting point for ribbon forming using fine powders. After solvent evaporation, the dispersant allows particles to settle into a tightly compacted unprocessed ribbon. Therefore, an effective dispersant can increase the density and strength of the unprocessed ribbon.

[0171] The advantages of the disclosed formulations include: (1) reduced costs (the dispersants, solvents, and binders disclosed herein can reduce raw material costs. Most importantly, the formulations developed herein can be used for continuous strip forming, allowing for high-volume production and reduced manufacturing costs); (2) high variability (based on the interaction between the dispersant and solvent, binder, and plasticizer, the acid to amine ratio can be varied to achieve the desired slurry properties for strip forming, such as pH, viscosity, settling velocity, etc. The chain length and structure of the organic acid or amine can also be selected based on hydrophobicity and compatibility with the solvent and interaction with the carrier film); (3) lower temperatures for organic matter removal can solve the burning of unprocessed strips during the debinding process (when using large... At 200°C, raw LCO ribbons exhibit combustion issues due to the exothermic reaction between oxygen released from LCO and organic materials. The dispersants described herein have lower heats of vaporization compared to polymeric dispersants, allowing them to evaporate below 200°C to limit thermal runaway in LCO; (4) greater tunability of the ribbon structure (compared to polymeric dispersants, better-dispersed single-molecule LCO particles have less steric hindrance, allowing the application of magnetic fields to achieve electrode design alignment, thereby improving energy density and realizing all solid-state Li-ion secondary batteries); (5) variability in size, shape, and thickness (the thickness of raw LCO ribbons can be produced in the range of 2-500 μm. Sintered LCO ribbons can be cut to designed sizes and shapes for application).

[0172] Unless otherwise expressly stated, it is not intended that any method illustrated herein require its steps to be performed in a particular order. Therefore, no particular order should be inferred when a method claim does not actually describe the order in which its steps are followed, or when the claims or specification do not otherwise specifically limit the steps to a particular order. Furthermore, as used herein, the article “a” is intended to include one or more components or elements and is not intended to be construed as referring to only one.

[0173] As used herein, the term “porosity” is described as a volume percentage (e.g., at least 10% by volume, or at least 30% by volume), where “porosity” refers to the portion of the volume of a sintered object that is not occupied by inorganic material.

[0174] As used herein, the terms “approximately,” “about,” “generally,” and similar terms are intended to have a broad meaning consistent with the common and accepted usage of those skilled in the art to which the subject matter of this disclosure pertains. Those skilled in the art to which this disclosure pertains will understand that these terms are intended to allow for the description of certain features described and claimed, without limiting the scope of such features to the precise numerical ranges provided. Therefore, these terms should be understood to indicate that non-substantial or insignificant modifications or alterations to the described and claimed subject matter are considered to be within the scope of the invention as enumerated in the appended claims.

[0175] As used herein, the terms "as the case may," "depending on the circumstances," or similar expressions are intended to mean that the event or situation subsequently described may or may not occur, and that the description includes both the possibility that the event or situation occurs and the possibility that it does not occur. The indefinite article "a / an" and its corresponding definite article "the" as used herein mean at least one, or one or more, unless otherwise specified. References to the position of elements herein (e.g., "top," "bottom," "above," "below," etc.) are used only to describe the orientation of the various elements in the accompanying drawings. It should be noted that the orientation of the various elements may differ according to other exemplary embodiments, and such variations are intended to be covered by this disclosure.

[0176] Regarding the use of any substantially plural and / or singular terms in this document, those skilled in the art may, depending on the context and / or application, convert from plural to singular and / or from singular to plural. For clarity, various singular / plural transformations are explicitly stated herein.

[0177] It will be apparent to those skilled in the art that various modifications and variations can be made without departing from the spirit or scope of the disclosed embodiments. Since modifications, combinations, sub-combinations, and variations of the disclosed embodiments incorporated into the spirit and substance of the embodiments are readily apparent to those skilled in the art, the disclosed embodiments should be understood to include each item within the scope of the appended claims and their equivalents.

Claims

1. A method for forming a sintered composition, comprising: Provide slurry precursors containing lithium, sodium, or magnesium-based compounds; The slurry precursor is strip-formed to form an unprocessed strip; and The unprocessed strip is sintered at a temperature ranging from 500°C to 1350°C for less than 60 minutes to form the sintered composition. The slurry precursor further comprises a solvent and a dispersant, wherein the dispersant comprises an amine compound and a carboxylic acid compound, wherein the ratio of the carboxylic acid compound to the amine compound is from at least 1:4 to less than 1:

1.

2. The method of claim 1, wherein the amine compound comprises oleylamine, dibutylamine, or a combination thereof.

3. The method of claim 1, wherein the amine compound comprises at least one amino group, at least one imine group, or a combination thereof. The at least one amino group or the at least one imine group contains an alkyl chain or an aromatic ring, and The amine compound mentioned above has fewer than 30 carbon atoms.

4. The method of claim 1, wherein the carboxylic acid compound comprises oleic acid.

5. The method of claim 1, wherein the carboxylic acid compound comprises an R-COOH structure molecule, wherein R is an alkyl chain or an aromatic ring, and wherein the R-COOH structure molecule has fewer than 30 carbon atoms.

6. The method of claim 1, wherein the ratio of the carboxylic acid compound to the amine compound is 1:4 to 1:

3.

7. The method of any one of claims 1-5, wherein the lithium, sodium, or magnesium-based compound has a D50 particle size of up to 0.6 μm.

8. The method according to any one of claims 1-5, wherein the solvent comprises 1-methoxy-2-propanediol, isopropanol, ethyl isobutyrate, ketones, aromatic hydrocarbons, amines, nitrated hydrocarbons, chlorinated hydrocarbons, or combinations thereof.

9. The method of any one of claims 1-5, wherein the lithium-based compound comprises at least one of the following: lithium cobalt oxide, lithium spinel manganese oxide, lithium nickel cobalt aluminate, lithium nickel manganese cobalt oxide, lithium iron phosphate, lithium cobalt phosphate, lithium titanate, lithium niobium tungstate, lithium titanium sulfide, or combinations thereof.

10. The method of any one of claims 1-5, wherein the lithium, sodium, or magnesium-based compound is at least 50 wt.% of the total slurry precursor.

11. The method according to any one of claims 1-5, wherein the sodium- or magnesium-based compound comprises at least one of: NaVPO4F; NaMnO2; Na 2 / 3 Mn 1-y Mg y O2, 0 < y < 1; Na2Li2Ti5O 12 Na2Ti3O7; MgCr2O4; or MgMn2O4.

12. The method of any one of claims 1-5, wherein the strip forming comprises: The slurry precursor is formed into a sheet configuration with a thickness in the range of 5 μm to 100 μm, and the slurry precursor further comprises a plasticizer; and The sheet configuration is dried such that the combination of the solvent, the dispersant, and the plasticizer does not exceed 10 wt. of the dried sheet.

13. The method of claim 12, further comprising: The dried sheet is debonded at a predetermined temperature ranging from 175°C to 350°C.

14. The method of claim 13, wherein the debonding and the sintering are performed simultaneously.

15. The method of any one of claims 1-5, wherein the sintering is performed for less than 45 minutes and includes continuously feeding the unprocessed strip through the sintering chamber at a predetermined rate.

16. The method of any one of claims 1-5, wherein, without further processing, directly after sintering, the final thickness of the sintered composition is in the range of 2 μm to 100 μm.

17. The method of any one of claims 1-5, wherein the strip forming comprises: The slurry precursor is continuously formed into a thin strip.

18. An energy device, comprising: A first sintered, unpolished electrode, the electrode having a first surface and a second surface; A first current collector, wherein the first current collector is disposed on the first surface of the first electrode; An electrolyte layer is disposed on the second surface of the first electrode; The second electrode is disposed on the electrolyte layer; and The second current collector is mounted on the second electrode. The first electrode comprises the sintered composition produced by the method as described in any one of claims 1-5.

19. The energy device of claim 18, wherein the electrolyte layer has at least 10 -6 Conductivity in S / cm.

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