Polymer electrolytes composed of a multielement oxide and applications thereof

Abstract

In accordance with the purpose(s) of the present disclosure, as embodied and broadly described herein, the disclosure, in one aspect, relates to multielement oxides. In one aspect, the multielement oxides have the AlTiXLiO, wherein X is Mg, Ni, Mn Cu, or any combination thereof. The multielement oxides are useful in preparing polymeric compositions having good mechanical and electrical properties, which makes them useful in lithium ion batteries.

Description

POLYMER ELECTROLYTES COMPOSED OF A MULTIELEMENT OXIDE AND APPLICATIONS THEREOFCROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of and priority to co-pending U.S. Provisional Patent Application No. 63 / 529,079, filed on July 26, 2023, the contents of which are incorporated by reference herein in their entireties.BACKGROUND

[0002] The use of lithium-ion batteries (LIBs) to power modern conveniences has been increasing over the past two decades. Despite cost reductions, many LIBs are facing more stringent performance requirements such as higher energy density, fast charging capabilities, improved safety, and longer cycling life. Current graphite anodes are nearing their limits to meet these performance demands, and new anodes are required. The ideal anode for future LIB is Li metal due to its high theoretical specific capacity (3860 mAh g-1), light weight (0.59 g cm'3), and lowest negative potential (-3.040 V vs. standard hydrogen electrode).1Unfortunately, due to Li dendrite growth during charge / discharge cycling, the Li metal anode has seen limited commercialized success.SUMMARY

[0003] In accordance with the purpose(s) of the present disclosure, as embodied and broadly described herein, the disclosure, in one aspect, relates to multielement oxides. In one aspect, the multielement oxides have the AITiXLiO, wherein X is Mg, Ni, Mn, Cu, or any combination thereof. The multielement oxides are useful in preparing polymeric compositions having good mechanical and electrical properties, which makes them useful in lithium ion batteries.

[0004] Other systems, methods, features, and advantages of the present disclosure will be or become apparent to one with skill in the art upon examination of the following drawings and detailed description. It is intended that all such additional systems, methods, features, and advantages be included within this description, be within the scope of the present disclosure, and be protected by the accompanying claims. In addition, all optional and preferred features and modifications of the described embodiments are usable in all aspects of the disclosure taught herein. Furthermore, the individual features of the dependent claims, as well as all optional andpreferred features and modifications of the described embodiments are combinable and interchangeable with one another.BRIEF DESCRIPTION OF THE DRAWINGS

[0005] Many aspects of the present disclosure can be better understood with reference to the following drawings. The components in the drawings are not necessarily to scale, emphasis instead being placed upon clearly illustrating the principles of the present disclosure. Moreover, in the drawings, like reference numerals designate corresponding parts throughout the several views.

[0006] FIGS. 1A-D show the schematic illustration of coin cell for (A) EIS measurements, (B) charge / discharge cycling, (C) LSV, and (D) over potential measurements.

[0007] FIGS. 2A-D show the characterization of MEO powder (A) SEM; (B) XRD of AITiMgLiO powder with assigned spinel phase planes; (C) SAED of AITiMgLiO powder with selected planes; and (D) elemental mapping of AITiMgLiO.

[0008] FIGS. 3A-F show the characterization of solid polymer electrolytes (A) SEM of SPE-0; (B) SEM of SPE-MEO-10; (C) SEM of SPE-MEO-60; (D) XRD of MEO, SPE-0, SPE-MEO-10, and SPE-MEO-60; (E) LSV of SPE scanning from 2.5 to 7 V and (F) Arrhenius plot of SPE ranging from 30 to 80°C.

[0009] FIGS. 4A-D show the EIS of SPE-0 at various temperatures. (A) Cell 1 (B) Cell 2. Inset for 50-80°C (C) Average bulk resistance. Inset EIS equivalent circuit (D) Bulk resistance values.

[0010] FIGS. 5A-D show the EIS of SPE-AI2O3-IO at various temperatures. (A) Cell 1 (B) Cell 2. Inset for 50-80°C (C) Average bulk resistance. Inset EIS equivalent circuit (D) Bulk resistance values.

[0011] FIGS. 6A-D show the EIS of SPE-MEO-10 at various temperatures. (A) Cell 1 (B) Cell 2. Inset for 50-80°C (C) Average bulk resistance. Inset EIS equivalent circuit (D) Bulk resistance values.

[0012] FIGS. 7A-D show the EIS of SPE-MEO-60 at various temperatures. (A) Cell 1 (B) Cell 2. Inset for 50-80°C (C) Average bulk resistance. Inset EIS equivalent circuit (D) Bulk resistance values.

[0013] FIG. 8 shows voltage polarization versus time for SPE-0 (black), SPE-AI2O3-IO (orange), and SPE-MEO-10 (blue) electrolytes at 20 pA cm-2.

[0014] FIGS. 9A-F show the electrochemical performance for LiFePC | SPE | Li at 80°C and 1C. Galvanostatic charge / discharge of select cycles for (A) SPE-0. (B) SPE-AI2O3-IO. (C) SPE-MEO- 10. Cycling performance and Coulombic efficiency of (D) SPE-0 (E) SPE-AI2O3-IO (F) SPE-MEO- 10.

[0015] FIG. 10 shows Discharge capacity loss per cycling region of different polymer matrices.

[0016] FIGS. 11A-H show SEM morphology of Li anodes after 100 cycles with low and high magnification. (A & E) Uncycled Li anode. (B & F) SPE-0. (C & G) SPE-AI2O3-IO. (D & H) SPE- MEO-10.

[0017] FIGS. 12A-D show the mechanism for reduction in dendritic growth with (A) fresh Li anode. (B) Cycled Li anode with SPE-0. (C) Cycled Li anode with SPE-AI2O3-W. (D) Cycled Li anode SPE-MEO-10.

[0018] Additional advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or can be learned by practice of the invention. The advantages of the invention will be realized and attained by means of the elements and combinations particularly pointed out in the appended claims. It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention, as claimed.DETAILED DESCRIPTION

[0019] Many modifications and other embodiments disclosed herein will come to mind to one skilled in the art to which the disclosed compositions and methods pertain having the benefit of the teachings presented in the foregoing descriptions and the associated drawings. Therefore, it is to be understood that the disclosures are not to be limited to the specific embodiments disclosed and that modifications and other embodiments are intended to be included within the scope of the appended claims. The skilled artisan will recognize many variants and adaptations of the aspects described herein. These variants and adaptations are intended to be included in the teachings of this disclosure and to be encompassed by the claims herein.

[0020] Although specific terms are employed herein, they are used in a generic and descriptive sense only and not for purposes of limitation.

[0021] As will be apparent to those of skill in the art upon reading this disclosure, each of the individual embodiments described and illustrated herein has discrete components and features which may be readily separated from or combined with the features of any of the other several embodiments without departing from the scope or spirit of the present disclosure.

[0022] Any recited method can be carried out in the order of events recited or in any other order that is logically possible. That is, unless otherwise expressly stated, it is in no way intended that any method or aspect set forth herein be construed as requiring that its steps be performed in a specific order. Accordingly, where a method claim does not specifically state in the claims or descriptions that the steps are to be limited to a specific order, it is no way intended that an order be inferred, in any respect. This holds for any possible non-express basis for interpretation, including matters of logic with respect to arrangement of steps or operational flow, plain meaning derived from grammatical organization or punctuation, or the number or type of aspects described in the specification.

[0023] All publications mentioned herein are incorporated herein by reference to disclose and describe the methods and / or materials in connection with which the publications are cited. The publications discussed herein are provided solely for their disclosure prior to the filing date of the present application. Nothing herein is to be construed as an admission that the present invention is not entitled to antedate such publication by virtue of prior invention. Further, the dates of publication provided herein can be different from the actual publication dates, which can require independent confirmation.

[0024] While aspects of the present disclosure can be described and claimed in a particular statutory class, such as the system statutory class, this is for convenience only and one of skill in the art will understand that each aspect of the present disclosure can be described and claimed in any statutory class.

[0025] It is also to be understood that the terminology used herein is for the purpose of describing particular aspects only and is not intended to be limiting. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the disclosed compositions and methods belong. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the specification and relevant art and should not be interpreted in an idealized or overly formal sense unless expressly defined herein.

[0026] Prior to describing the various aspects of the present disclosure, the following definitions are provided and should be used unless otherwise indicated. Additional terms may be defined elsewhere in the present disclosure.Definitions

[0027] As used herein, “comprising” is to be interpreted as specifying the presence of the stated features, integers, steps, or components as referred to, but does not preclude the presence or addition of one or more features, integers, steps, or components, or groups thereof. Moreover, each of the terms “by”, “comprising,” “comprises”, “comprised of,” “including,” “includes,” “included,” “involving,” “involves,” “involved,” and “such as” are used in their open, non-limiting sense and may be used interchangeably. Further, the term “comprising” is intended to include examples and aspects encompassed by the terms “consisting essentially of” and “consisting of.” Similarly, the term “consisting essentially of” is intended to include examples encompassed by the term “consisting of.

[0028] As used in the specification and the appended claims, the singular forms “a,” “an” and “the” include plural referents unless the context clearly dictates otherwise. Thus, for example, reference to “an excipient” include, but are not limited to, mixtures or combinations of two or more such excipients, and the like.

[0029] It should be noted that ratios, concentrations, amounts, and other numerical data can be expressed herein in a range format. It will be further understood that the endpoints of each of the ranges are significant both in relation to the other endpoint, and independently of the other endpoint. It is also understood that there are a number of values disclosed herein, and that each value is also herein disclosed as “about” that particular value in addition to the value itself. For example, if the value “10” is disclosed, then “about 10” is also disclosed. Ranges can be expressed herein as from “about” one particular value, and / or to “about” another particular value. Similarly, when values are expressed as approximations, by use of the antecedent “about,” it will be understood that the particular value forms a further aspect. For example, if the value “about 10” is disclosed, then “10” is also disclosed.

[0030] When a range is expressed, a further aspect includes from the one particular value and / or to the other particular value. For example, where the stated range includes one or both of the limits, ranges excluding either or both of those included limits are also included in the disclosure, e.g. the phrase “x to y” includes the range from ‘x’ to ‘y’ as well as the range greater than ‘x’ and less than ‘y’. The range can also be expressed as an upper limit, e.g. 'about x, y, z, or less’ andshould be interpreted to include the specific ranges of ‘about x’, ‘about y’, and ‘about z’ as well as the ranges of ‘less than x’, less than y’, and ‘less than z’. Likewise, the phrase ‘about x, y, z, or greater’ should be interpreted to include the specific ranges of ‘about x’, ‘about y’, and ‘about z’ as well as the ranges of ‘greater than x’, greater than y’, and ‘greater than z’. In addition, the phrase “about ‘x’ to ‘y’”, where ‘x’ and ‘y’ are numerical values, includes “about ‘x’ to about ‘y’”.

[0031] It is to be understood that such a range format is used for convenience and brevity, and thus, should be interpreted in a flexible manner to include not only the numerical values explicitly recited as the limits of the range, but also to include all the individual numerical values or subranges encompassed within that range as if each numerical value and sub-range is explicitly recited. To illustrate, a numerical range of “about 0.1 % to 5%” should be interpreted to include not only the explicitly recited values of about 0.1% to about 5%, but also include individual values (e.g., about 1%, about 2%, about 3%, and about 4%) and the sub-ranges (e.g., about 0.5% to about 1.1%; about 5% to about 2.4%; about 0.5% to about 3.2%, and about 0.5% to about 4.4%, and other possible sub-ranges) within the indicated range. Thus, for example, if a component is in an amount of about 1%, 2%, 3%, 4%, or 5%, where any value can be a lower and upper endpoint of a range, then any range is contemplated between 1% and 5% (e.g., 1% to 3%, 2% to 4%, etc.).

[0032] As used herein, the terms “about,” “approximate,” “at or about,” and “substantially” mean that the amount or value in question can be the exact value or a value that provides equivalent results or effects as recited in the claims or taught herein. That is, it is understood that amounts, sizes, formulations, parameters, and other quantities and characteristics are not and need not be exact, but may be approximate and / or larger or smaller, as desired, reflecting tolerances, conversion factors, rounding off, measurement error and the like, and other factors known to those of skill in the art such that equivalent results or effects are obtained. In some circumstances, the value that provides equivalent results or effects cannot be reasonably determined. In such cases, it is generally understood, as used herein, that “about” and “at or about” mean the nominal value indicated ±10% variation unless otherwise indicated or inferred. In general, an amount, size, formulation, parameter or other quantity or characteristic is “about,” “approximate,” or “at or about” whether or not expressly stated to be such. It is understood that where “about,” “approximate,” or “at or about” is used before a quantitative value, the parameter also includes the specific quantitative value itself, unless specifically stated otherwise.

[0033] Unless otherwise expressly stated, it is in no way intended that any method set forth herein be construed as requiring that its steps be performed in a specific order. Accordingly, where a method claim does not actually recite an order to be followed by its steps or it is not otherwise specifically stated in the claims or descriptions that the steps are to be limited to a specific order, it is no way intended that an order be inferred, in any respect. This holds for any possible nonexpress basis for interpretation, including: matters of logic with respect to arrangement of steps or operational flow; plain meaning derived from grammatical organization or punctuation; and the number or type of embodiments described in the specification.

[0034] Disclosed are the components to be used to prepare the compositions of the invention as well as the compositions themselves to be used within the methods disclosed herein. These and other materials are disclosed herein, and it is understood that when combinations, subsets, interactions, groups, etc. of these materials are disclosed that while specific reference of each various individual and collective combinations and permutation of these compounds cannot be explicitly disclosed, each is specifically contemplated and described herein. For example, if a particular compound is disclosed and discussed and a number of modifications that can be made to a number of molecules including the compounds are discussed, specifically contemplated is each and every combination and permutation of the compound and the modifications that are possible unless specifically indicated to the contrary. Thus, if a class of molecules A, B, and C are disclosed as well as a class of molecules D, E, and F and an example of a combination molecule, A-D is disclosed, then even if each is not individually recited each is individually and collectively contemplated meaning combinations, A-E, A-F, B-D, B-E, B-F, C-D, C-E, and C-F are considered disclosed. Likewise, any subset or combination of these is also disclosed. Thus, for example, the sub-group of A-E, B-F, and C-E would be considered disclosed. This concept applies to all aspects of this application including, but not limited to, steps in methods of making and using the compositions of the invention. Thus, if there are a variety of additional steps that can be performed it is understood that each of these additional steps can be performed with any specific embodiment or combination of embodiments of the methods of the invention.

[0035] It is understood that the compositions disclosed herein have certain functions. Disclosed herein are certain structural requirements for performing the disclosed functions, and it is understood that there are a variety of structures that can perform the same function that are related to the disclosed structures, and that these structures will typically achieve the same result.

[0036] As used herein, the terms “optional” or “optionally” means that the subsequently described event or circumstance can or cannot occur, and that the description includes instances where said event or circumstance occurs and instances where it does not.

[0037] Unless otherwise specified, temperatures referred to herein are based on atmospheric pressure (i.e. one atmosphere).Multielement Oxide Compounds and Methods of Making and Using the Same

[0038] Due to Li dendrite growth during charge / discharge cycling, the Li metal anode in lithium- ion batteries (LIBs) has seen limited commercialized success. To address these shortcomings, polymers such as polyethylene oxide (PEO) with fillers such as TiO2, AI2O3, LiAIO2, and Li3N have been added to the polymer matrix to increase their electrochemical and mechanical properties. While incorporating additives into the polymer structure can improve mechanical performance by increasing the shear and elastic modulus, at high weight percentages, these additives can cause adverse effects on the electrochemical properties and processability of the polymer.

[0039] Described herein are multielement oxides (MEO) as a filler for solid polymer electrolytes (SPE). The MEOs described herein, due to synergistic contributions of elements, provide high chemical, structural, and electrochemical stability. These benefits make multielement compounds described herein useful for improving the performance of SPE.

[0040] In one aspect, the MEO comprises the formula AITiXLiO, wherein X is Mg, Ni, Mn Cu, or any combination thereof. In another aspect, the MEO consists essentially of the formula AITiXLiO, wherein X is Mg, Ni, Mn Cu, or any combination thereof. In another aspect, the MEO consists of the formula AITiXLiO, wherein X is Mg, Ni, Mn Cu, or any combination thereof. In another aspect, X is Mg in each of the previous aspects.

[0041] By varying the relative amounts of the different elements present in the MEO, the mechanical and electrical properties can be fine-tuned for specific applications. In one aspect, the weight ratio of Al to Ti in the MEO is from 1 :1 to 3:1. In another aspect, the weight ratio of Al to Ti in the MEO is 1 :1 , 1:25:1 , 1.5:1 , 1.75:1 , 2:1, 2.25:1 , 2.5:1 , 2.75:1, or 3:1 , where any value can be a lower and upper endpoint of a range (e.g., 1 :1 to 2:1, etc.).

[0042] In one aspect, the weight ratio of Al to X in the MEO is from 1 :1 to 4:1. In another aspect, the weight ratio of Al to X in the MEO is 1 :1, 1 :25:1 , 1.5:1 , 1.75:1, 2:1 , 2.25:1 , 2.5:1, 2.75:1 , 3:1 , 3:25:1 , 3.3:1 , 3.75:1 , or 4:1 where any value can be a lower and upper endpoint of a range (e.g., 2:1 to 3:1, etc.).

[0043] In one aspect, the weight ratio of Ti to X in the MEO is from 1 :1 to 3:1. In another aspect, the weight ratio of Al to Ti in the MEO is 1 :1 , 1:25:1, 1.5:1 , 1.75:1 , 2:1 , 2.25:1 , 2.5:1, 2.75:1 , or 3:1 , where any value can be a lower and upper endpoint of a range (e.g., 1 :1 to 2:1 , etc.).

[0044] In one aspect, Al is from about 10 weight percent to about 30 weight percent of the MEO. In another aspect, Al is from about 10 weight percent, 12.5 weight percent, 15 weight percent,17.5 weight percent, 20 weight percent, 22.5 weight percent, 25 weight percent, 27.5 weight percent, or 30 weight percent, where any value can be a lower and upper endpoint of a range (e.g., 12.5 weight percent to 25 weight percent, etc.).

[0045] In one aspect, Ti is from about 10 weight percent to about 20 weight percent of the MEO. In another aspect, Ti is from about 10 weight percent, 12.5 weight percent, 15 weight percent,17.5 weight percent, or 20 weight percent, where any value can be a lower and upper endpoint of a range (e.g., 12.5 weight percent to 17.5 weight percent, etc.).

[0046] In one aspect, X is from about 10 weight percent to about 20 weight percent of the MEO. In another aspect, X is from about 10 weight percent, 12.5 weight percent, 15 weight percent,17.5 weight percent, or 20 weight percent, where any value can be a lower and upper endpoint of a range (e.g., 12.5 weight percent to 17.5 weight percent, etc.).

[0047] In one aspect, Li is from about 1 weight percent to about 10 weight percent of the MEO. In another aspect, Li is from about 1 weight percent, 2.5 weight percent, 5 weight percent, 7.5 weight percent, or 10 weight percent, where any value can be a lower and upper endpoint of a range (e.g., 2.5 weight percent to 7.5 weight percent, etc.).

[0048] In one aspect, the MEO has the formula AlaTibXcLidOe, wherein a is from 0.15 to 0.25; b is from 0.10 to 0.15; c is from 0.05 to 0.10; d is from 0.005 to 0.01 ; and e is from 0.50 to 0.60, wherein the sum of a, b, c, d, and e is 1.0.

[0049] In one aspect, the MEO has the formula AlaTibMgcLidOe, where a-e are as defined above.

[0050] In one aspect, the MEO described herein has cubic spinel crystal phase. In another aspect, the MEO has an X-ray powder diffraction pattern comprising peaks at 31.3° and 36.0° ± 0.2° 20 as measured by X-ray powder diffraction using an X-ray wavelength of 1.5418 A. Inanother aspect, the MEO has an X-ray powder diffraction pattern comprising peaks at 31.3°, 36.0°, and 44.9° ± 0.2° 29 as measured by X-ray powder diffraction using an X-ray wavelength of 1.5418 A. In another aspect, the MEO has an X-ray powder diffraction pattern comprising peaks at 31 .3°, 36.0°, and 44.9°, and 65.4° ± 0.2° 20 as measured by X-ray powder diffraction using an X-ray wavelength of 1.5418 A. Methods for determining the X-ray powder diffraction pattern of the MEOs are provided in the Examples.

[0051] In one aspect, the MEO is AITiMgLiO having an X-ray powder diffraction pattern comprising peaks at 31.3° and 36.0° ± 0.2° 29 as measured by X-ray powder diffraction using an X-ray wavelength of 1.5418 A. In another aspect, the MEO is AITiMgLiO having an X-ray powder diffraction pattern comprising peaks at 31.3°, 36.0°, and 44.9° ± 0.2° 20 as measured by X-ray powder diffraction using an X-ray wavelength of 1.5418 A. In another aspect, the MEO is AITiMgLiO having an X-ray powder diffraction pattern comprising peaks at 31 .3°, 36.0°, and 44.9°, and 65.4° ± 0.2° 20 as measured by X-ray powder diffraction using an X-ray wavelength of 1.5418 A.

[0052] In one aspect, the MEO has an average particle size of about 150 nm to about 250 nm. In another aspect, the MEO has an average particle size of about 150 nm, 175 nm, 200 nm, 225 nm, or 250 nm, where any value can be a lower and upper endpoint of a range (e.g., 2.5 weight percent to 7.5 weight percent, etc.). Methods for determining the average particle size of the MEOs are provided in the Examples.

[0053] Described herein are methods for making MEOs. In one aspect, the method involves(a) mixing in the solid state the following components: (i) AI2O3; (ii) TiO2; (iii) XO, wherein X is Mg, Ni, Mn Cu, or any combination thereof; and (iv) a lithium ion source to produce a first mixture, and(b) heating the first mixture at a temperature of about 800 °C to about 1 ,200 °C.

[0054] The compounds used to produce the electrolytes described herein are generally highly pure materials. In one aspect, each of the compounds has a purity of greater than 99%, greater than 99.5%, or greater than 99.9%. In one aspect, each compound used to produce the electrolytes is substantially anhydrous, where each compound is at least 95% moisture free, at least 98% moisture free, at least 99% moisture free, at least 99.9% moisture free, or 100% moisture free. In another aspect, each compound has less than 0.5 ppm water, less than 0.25 ppm water, or less than 0.1 ppm water.

[0055] The lithium ion source is any compound that provides or produces lithium ions. In one aspect, the lithium source is lithium oxide. In another aspect, the lithium source is a lithium salt such as, for example, LiPF6, LiBF4, LiCIO4, lithium bis(fluorosulfonyl)amide, lithium bis(trifluoromethane)sulfonylamide, lithium bis(oxalato)borate, LiAsF6, LiPF3(CF2CF3)3 , lithium triflate, lithium dodecyl sulfate, lithium bis(trifluoromethanesulfonyl)imide, lithium bis(pentafluoroethanesulfonyl)imide, lithium difluoro(ethanedioato)borate, lithium bis(monofluoromalonato)borate, lithium 4,5-dicyano-1 ,2,3-triazolate, lithium 4,5-dicyano-2- trifluoromethylimidazole, or any combination thereof.

[0056] In one aspect, in step (a) the compounds can be mixed by mechanochemical milling. Mixing of the compounds can occur in a mixing jar or container using one or more balls to produce a complex motion that combines back-and-forth swings with short lateral movements. In one aspect, the compounds are mixed with one another for at least three hours. In another aspect, the compounds are mixed from about 100 minutes to about 500 minutes. In one aspect, the compounds are mixed in the presence of air or oxygen. In another aspect, the compounds are mixed in an inert atmosphere such as, for example, nitrogen or argon.

[0057] The amount of each component used to produce the MEO. In one aspect, equimolar amounts or ± 1 % to 10% of each component can be used to prepare the MEO.

[0058] After mixing the components are mixed in step (a), the first mixture is heated at a temperature of about 800 °C to about 1 ,200 °C. In another aspect, the first mixture is heated at a temperature of about 800 °C, 850 °C, 900 °C, 950 °C, 1 ,000 °C, 1 ,050 °C, 1 ,100 °C, 1 ,150 °C, or 1,200 °C, where any value can be a lower and upper endpoint of a range (e.g., 1 ,000 °C to 1 ,100 °C, etc.). In one aspect, The first mixture can be heated from 1 hour to 24 hours. After heating, the MEO can be ground to form a powder. Nonlimiting methods for producing the MEOs described herein are provided in the Examples.

[0059] The MEOs described herein can be used to produce polymeric compositions as a substitute of liquid polyelectrolytes in lithium batteries. The polymeric compositions described herein are also referred to as solid polymer electrolytes or SPEs.

[0060] In one aspect, the polymeric composition includes a mixture of a polymer, a lithium ion source, and a MEO as described herein. The polymer can be any material typically used to produce lithium batteries.

[0061] In one aspect, the polymer is polyacrylonitrile (PAN); polycarbonates (PC); polyesters andpolylactones, for example polycaprolactone (PCL); poly(meth)acrylate esters, such as poly(methyl methacrylate) (PMMA).

[0062] In another aspect, the polymer is a polyalkylene oxide homopolymer or copolymer, where the polymer has repeat units of -(CH2)n-, where n is an integer from 1 to 5. In one aspect, the polyalkylene oxide is polyethylene oxide, polypropylene oxide, or a combination thereof. In another aspect, polyalkylene oxide is a polyethylene oxide-polypropylene oxide copolymer (e.g., random or block copolymer).

[0063] In one aspect, the polymer has an average molecular weight from 250 kDa to 1 ,500 kDa. In another aspect, polymer has an average molecular weight of 250 kDa, 500 kDa, 750 kDa, 1 ,000 kDa, 1 ,250 kDa, or 1,500 kDa, where any value can be a lower and upper endpoint of a range (e.g., 500 kDa to 750 kDa, etc.). In another aspect, the polymer is polyethylene oxide having an average molecular weight from 250 kDa to 750 kDa, or 250 kDa, 300 kDa, 350 kDa, 400 kDa, 450 kDa, 500 kDa, 550 kDa, 600 kDa, 650 kDa, 700 kDa, or 750 kDa, where any value can be a lower and upper endpoint of a range (e.g., 500 kDa to 700 kDa, etc.).

[0064] In one aspect, the polymeric composition can be produced by mixing the polymer, the lithium ion source, and the MEO together in a solvent. In one aspect, the components are mixed together to ensure all components are homogeneously mixed together so that the lithium ion source and MEO are homogeneously dispersed throughout the polymer. In one aspect, the solvent is an organic solvent such as, for example, acetonitrile or tetrahydrofuran. The lithium ion source can be any of the compounds described above.

[0065] Once the mixture of polymer, lithium ion source, and MEO has been produced, the mixture can be processed to produce a solid polymeric material. In one aspect, the mixture can be cast to produce a film of desired thickness. In other aspect, the mixture can be spun (e.g., electrospun) to produce fibers (e.g., nanofibers or nano whiskers). Nonlimiting methods for producing the polymeric compositions described herein are provided in the Examples.

[0066] The amount of th MEO incorporated into the polymeric compositions can be varied to modify the mechanical and electrical properties of the composition. In one aspect, the MEO is from 5 weight % to about 75 weight percent of the composition. In another the MEO is 5 weight %, 10 weight %, 15 weight %, 20 weight %, 25 weight %, 30 weight %, 35 weight %, 40 weight %, 45 weight %, 50 weight %, 55 weight %, 60 weight %, 65 weight %, 70 weight %, or 75 weight %, where any value can be a lower and upper endpoint of a range (e.g., 5 weight % to 15 weight %, etc.).

[0067] In one aspect, the polymeric composition has an X-ray powder diffraction pattern comprising peaks at 19.1° and 23.3° ± 0.2° 20 as measured by X-ray powder diffraction using an X-ray wavelength of 1.5418 A. In another aspect, the polymeric composition includes polyethylene oxide and AITiMgLiO as the MEO having an X-ray powder diffraction pattern comprising peaks at 19.1° and 23.3° ± 0.2° 20 as measured by X-ray powder diffraction using an X-ray wavelength of 1.5418 A.

[0068] The polymeric compositions described herein possess several desirable electrical properties that make them suitable for lithium ion batteries. Moreover, the use of the MEOs described herein provide improved electrical properties when compared to the polymeric composition produced from single element fillers (e.g., AI2O3).

[0069] In one aspect, the polymeric composition has an ionic conductivity of about 1.00 x 10"6S / cm to about 3.00 x 10'6S / cm at 30 °C. In another aspect, the polymeric composition has an ionic conductivity of about 1.00 x 10"6S / cm, 1.25 x 10"6S / cm, 1.50 x 10"6S / cm, 1.75 x 10’6S / cm, 2.00 x 10’6S / cm, 2.25 x 10’6S / cm, 2.50 x 10’6S / cm, 2.75 x 10’6S / cm, or 3.00 x 10’6S / cm, where any value can be a lower and upper endpoint of a range (e.g., 500 kDa to 700 kDa, etc.). Methods for determining the ionic conductivity of the polymeric compositions described herein are provided in the Examples.

[0070] In another aspect, the polymeric composition has a lithium transference number of 0.40 to 0.50. In another aspect, the polymeric composition has a lithium transference number of 0.40, 0.41, 0.42, 0.43, 0.44, 0.45, 0.46, 0.47, 0.48, 0.49, or 0.50, where any value can be a lower and upper endpoint of a range (e.g., 0.41 to 0.45, etc.). Methods for determining the lithium transference of the polymeric compositions described herein are provided in the Examples.

[0071] In another aspect, the polymeric composition has an electrochemical stability of 6.0 V to 7.0 V. In another aspect, the polymeric composition has an electrochemical stability of 6.0 V, 6.1 V, 6.2 V, 6.3 V, 6.4 V, 6.5 V, 6.6 V, 6.7 V, 6.8 V, 6.9 V, or 7.0 V, where any value can be a lower and upper endpoint of a range (e.g., 6.2 V to 6.8, etc.). Methods for determining the electrochemical stability of the polymeric compositions described herein are provided in the Examples.

[0072] The polymeric composition described herein have high capacity retention after several cycles, which is another important feature or attribute when preparing lithium ion batteries. In one aspect, the polymeric composition after 50 cycles has a capacity retention of at least 95% of the same composition prior to cycling. In another aspect, the polymeric composition after 50 cycleshas a capacity retention of 95%, 96%, 97%, 98%, 99%, 99.5%, or 99.9% of the same composition prior to cycling, where any value can be a lower and upper endpoint of a range (e.g., 96% to 99%, etc.). In another aspect, the polymeric composition after 500 cycles has a capacity retention of at least 75% of the same composition prior to cycling. In another aspect, the polymeric composition after 50 cycles has a capacity retention of 75%, 80%, 85%, 90%, 95%, or 99% of the same composition prior to cycling, where any value can be a lower and upper endpoint of a range (e.g., 80% to 90%, etc.). Methods for determining the capacity retention of the polymeric compositions described herein after cycling are provided in the Examples.

[0073] The polymeric compositions described herein can be used to produce lithium batteries. In one aspect, the lithium battery includes a positive electrode, a negative electrode, and the polymeric composition as described herein, wherein the polymeric composition is positioned between the positive electrode and the negative electrode.

[0074] In one aspect, the positive active material (i.e. , cathode active material) to be used as the positive electrode (cathode) active material layer has average operating potential greater than 2 V (vs. Li+ / Li), preferably 2.0 V to 6.0 V, more preferably 3.0 V to 5.0 V. The average operating potential can be evaluated using cyclic voltammetry, for example.

[0075] In one aspect, the positive active material has a spinel type structure denoted by general formula UM2O4, where M is at least one kind of transition metal element. In one aspect, M can be Ni, Mn, Cr, Co, V, and Ti. In one aspect, LiCr0.05Ni0.50Mn1.45O4, LiCrMnO4, LiNio.5Mn1.5O4, etc. can be used as the material for the positive electrode. In another aspect, the positive active material is LiFePO4, LiCoO2, or NiCoAIO2.

[0076] In other aspects, a positive active material layer may contain an electrically conductive agent to improve the conductivity of a positive active material layer. In one aspect, acetylene black, Ketjenblack, a carbon fiber, carbon nanotube (CNT), carbon nanofibers (CNF) etc. can be used. The positive active material may also contain a binding agent. As such a binding material (binding agent), fluorine-based binding materials, such as polyvinylidene fluoride (PVDF) and polytetrafluoroethylene (PTFE), etc. can be used, for example. CMC, cellulose and similar biosourced binding agents can be used with water-based processes.

[0077] The thickness of the positive active material layer can be modified according to the battery that is produced. In one aspect, the thickness of the positive active material layer is from 0.1 pm to 500 pm. In another aspect, the positive electrode is dried before assembly. This drying process may also appropriately be applied for negative electrode as well.

[0078] In one aspect, the composition of the negative electrode active material layer includes one or more negative electrode active material(s), and may additionally contain at least one or more of solid electrolyte materials and electrically conductive agents if needed. For the lithium batteries described herein, the negative electrode active material is not limited provided that occlusion and discharge of the Li ion, which is a conduction ion, are possible. In one aspect, the negative electrode active material can be a carbon active material, a metal active material. In another aspect, a carbon active material, black lead, mesocarbon microbeads (MCMB), highly ordered / oriented pyrolytic graphite (HOPG), hard carbon, soft carbon, etc. can be used. In another aspect, an alloy, such as Li alloy and Sn — Co — C, In, Al, Si, Sn, etc. can be used as the negative electrode active material layer. In another aspect, oxide stock materials, such as Li4Ti5Oi2 or TiO2, can also be used as the negative electrode active material. In another aspect, the negative electrode active material is lithium metal (Li metal).

[0079] Common manufacturing methods can be used to manufacture the lithium batteries described herein. For example, when the battery is in the form of a thin film, a positive active material layer can be formed on a substrate followed by forming a layer composed of a polymeric composition described herein and a negative electrode active material layer, and laminating them thereafter.

[0080] The lithium battery incorporating the polymeric compositions described herein can be assembled in a monopolar or bipolar configurations. A monopolar configuration is a stack of two or more (n) same simple cells. In this configuration a same current collector (metal foil) is shared between positive electrode of cell number n and positive electrode of cell number (n-1). In this aspect, the monopolar configuration cell has the same voltage as one cell but with n times the capacity of 1 simple cell.

[0081] A bipolar configuration is a stack of two or more (n) same simple cells. In this configuration a same current collector (metal foil) is shared between positive electrode of cell number n and negative electrode of cell number (n-1). In this aspect, the bipolar configuration cell has the same capacity as one cell but with n times the voltage of one simple cell.Aspects

[0082] Aspect 1. A compound having the formula AITiXLiO, wherein X is Mg, Ni, Mn Cu, or any combination thereof.

[0083] Aspect 2. The compound of Aspect 1 , wherein X is Mg.

[0084] Aspect 3. The compound of Aspect 1or 2, wherein the weight ratio of Al to Ti is from 1:1 to 3:1.

[0085] Aspect 4. The compound of any one of Aspects 1-3, wherein the weight ratio of Al to X is from 1 :1 to 4: 1 .

[0086] Aspect 5. The compound of any one of Aspects 1-4, wherein the weight ratio of Ti to X is from 1 :1 to 3: 1 .

[0087] Aspect 6. The compound of any one of Aspects 1-5, wherein Al is from about 10 weight percent to about 30 weight percent of the compound.

[0088] Aspect 7. The compound of any one of Aspects 1-6, wherein Ti is from about 10 weight percent to about 20 weight percent of the compound.

[0089] Aspect 8. The compound of any one of Aspects 1-7, wherein X is from about 10 weight percent to about 20 weight percent of the compound.

[0090] Aspect 9. The compound of any one of Aspects 1-8, wherein Li is from about 1 weight percent to about 10 weight percent of the compound.

[0091] Aspect 10. The compound of Aspect 1 , wherein the compound has the formulaAlaTibXcLidOe, wherein a is from 0.15 to 0.25; b is from 0.10 to 0.15; c is from 0.05 to 0.10; d is from 0.005 to 0.01 ; and e is from 0.50 to 0.60, wherein the sum of a, b, c, d, and e is 1.0.

[0092] Aspect 11. The compound of Aspect 1 , wherein X is Mg.

[0093] Aspect 12. The compound of any one of Aspects 1-11 , wherein the compound has an average particle size of about 150 nm to about 250 nm.

[0094] Aspect 13. The compound of any one of Aspects 1-12, wherein the compound has cubic spinel crystal phase.

[0095] Aspect 14. The compound of any one of Aspects 1-13, wherein the compound has an X-ray powder diffraction pattern comprising peaks at 15.6° and 36.9° ± 0.2° 20 as measured by X- ray powder diffraction using an X-ray wavelength of 1.5418 A.

[0096] Aspect 15. The compound of any one of Aspects 1-13, wherein the compound has an X- ray powder diffraction pattern comprising peaks at 15.6°, 36.9°, and 44.8° ± 0.2° 20 as measured by X-ray powder diffraction using an X-ray wavelength of 1.5418 A.

[0097] Aspect 16. The compound of any one of Aspects 1-13, wherein the compound has an X- ray powder diffraction pattern comprising peaks at 15.6°, 36.9°, 44.8°, and 65.5° ± 0.2° 20 as measured by X-ray powder diffraction using an X-ray wavelength of 1.5418 A.

[0098] Aspect 17. A compound produced by the method comprising(a) mixing in the solid state the following components: (i) AI2O3; (ii) TiO2; (iii) XO, wherein X is Mg, Ni, Mn Cu, or any combination thereof; and (iv) a lithium ion source to produce a first mixture, and(b) heating the first mixture at a temperature of about 800 °C to about 1 ,200 °C.

[0099] Aspect 18. The compound of Aspect 17, wherein the components are mixed by mechanochemical milling.

[0100] Aspect 19. A polymeric composition comprising a polymer, a lithium ion source, and the compound of any one of Aspects 1-18.

[0101] Aspect 20. The composition of Aspect 19, wherein the polymer comprises a polyalkylene oxide homopolymer or copolymer.

[0102] Aspect 21. The composition of Aspect 19, wherein the polymer comprises a polyethylene oxide, polypropylene oxide, or a combination thereof.

[0103] Aspect 22. The composition of any one of Aspects 19-21 , wherein the polymer has an average molecular weight from 250 kDa to 1 ,500 kDa.

[0104] Aspect 23. The composition of Aspect 19, wherein the polymer is polyethylene oxide having an average molecular weight from 250 kDa to 750 kDa.

[0105] Aspect 24. The composition of any one of Aspects 19-23, wherein compound is from 5 weight % to about 75 weight percent of the composition.

[0106] Aspect 25. The composition of any one of Aspects 19-23, wherein compound is from 5 weight % to about 15 weight percent of the composition.

[0107] Aspect 26. The composition of any one of Aspects 19-25, wherein the lithium ion source comprises LiPF6, LiBF4, LiCIO4, lithium bis(fluorosulfonyl)amide, lithium bis(trifluoromethane)sulfonylamide, lithium bis(oxalato)borate, LiAsF6, LiPF3(CF2CF3)3 , lithium triflate, lithium dodecyl sulfate, lithium bis(trifluoromethanesulfonyl)imide, lithium bis(pentafluoroethanesulfonyl)imide, lithium difluoro(ethanedioato)borate, lithium bis(monofluoromalonato)borate, lithium 4,5-dicyano-1 ,2,3-triazolate, lithium 4,5-dicyano-2- trifluoromethylimidazole, lithium oxide, or any combination thereof.

[0108] Aspect 27. The composition of any one of Aspects 19-26, wherein the composition has an X-ray powder diffraction pattern comprising peaks at 19.1° and 23.3° ± 0.2° 29 as measured by X-ray powder diffraction using an X-ray wavelength of 1.5418 A.

[0109] Aspect 28. The composition of any one of Aspects 19-27, wherein the composition has an ionic conductivity of about 1.00 x 10"6S / cm to about 3.00 x 10'6S / cm at 30 °C.

[0110] Aspect 29. The composition of any one of Aspects 19-28, wherein the composition has a lithium transference number of 0.40 to 0.50.

[0111] Aspect 30. The composition of any one of Aspects 19-29, wherein the composition has an electrochemical stability of 6.0 to 7.0 V.

[0112] Aspect 31. The composition of any one of Aspects 19-30, wherein the composition after 50 cycles has a capacity retention of at least 95% of the same composition prior to cycling.

[0113] Aspect 32. The composition of any one of Aspects 19-30, wherein the composition after 500 cycles has a capacity retention of at least 75% of the same composition prior to cycling.

[0114] Aspect 33. A lithium battery comprising a positive electrode, a negative electrode, and the polymeric composition of any one of Aspects 19-32, wherein the polymeric composition is positioned between the positive electrode and the negative electrode.

[0115] Now having described the aspects of the present disclosure, in general, the following Examples describe some additional aspects of the present disclosure. While aspects of the present disclosure are described in connection with the following examples and the corresponding text and figures, there is no intent to limit aspects of the present disclosure to this description. On the contrary, the intent is to cover all alternatives, modifications, and equivalents included within the spirit and scope of the present disclosure.EXAMPLES

[0116] The following examples are put forth so as to provide those of ordinary skill in the art with a complete disclosure and description of how the compounds, compositions, articles, devices and / or methods claimed herein are made and evaluated, and are intended to be purely exemplary of the disclosure and are not intended to limit the scope of what the inventors regard as their disclosure. Efforts have been made to ensure accuracy with respect to numbers (e.g., amounts, temperature, etc.), but some errors and deviations should be accounted for. Unless indicated otherwise, parts are parts by weight, temperature is in °C or is at ambient temperature, and pressure.Materials and Methods

[0117] Materials

[0118] Polyethylene oxide (PEO) (Mw= 1 000 000), Bis(trifluoromethane)sulfonamide lithium salt (LiTFSI, 99.95% trace metals basis), and Acetonitrile (>99.9%) were purchased from Sigma Aldrich and used as received. The multielement oxide fillers were synthesized using a ball milling and sintering technique.2627Precursors for the MEO (AITiMgLiO) of aluminum oxide (>98% AI2O3), titanium (IV) oxide (nanopowder <25 nm, 99.7%), magnesium oxide (>99%, -325 mesh) and lithium carbonate (99.997%) were purchased from Sigma Aldrich and used as received.

[0119] Preparation of MEO additives

[0120] The MEO fillers was synthesized using a ball milling and sintering technique. The binary metal oxide precursors were combined in equimolar amounts (0.002 mols) and ball milled using a SPEX SamplePrep Mixer / M ill 8000M for 300 min. After ball milling, the powder was pressed into a 15 mm pellet at 250 MPa. The pellet was then free sintered in a Thermo Scientific Lindberg Blue M oven at 1020°C for 12 h. After sintering, the pellet was ball milled back into a powder.

[0121] Preparation of PEO- based solid polymer electrolytes

[0122] The PEO-based solid polymers were prepared by a solution casting method. A stock solution of 500 mg of PEO and 181.04 mg of LiTFSI salt was dissolved in acetonitrile. The salt concentration was kept constant in all SPE at EO:Li = 18. Various amounts of the MEO powder were added to each stock solution. Three sets of samples were made for study consisting of no additive, 10wt% MEO additive, and 60wt% MEO additive referred to as SPE-0, SPE-MEO-10, and SPE-MEO-60. The polymer with no additive served as a control case. The 10wt% MEO fillerwas the result of a concentration study to find the polymer with the highest ionic conductivity at room temperature. The 60wt% MEO additive SPE was used as an extreme case of additive to study the effects of high concentrations. For additional electrochemical comparison, SPEs were cycled with a unary composition made with 10wt% filler of AI2O3, referred to as SPE-AhCh-IO. The solution was stirred for 8 h at room temperature until well mixed. The slurry was then cast into a Teflon petri dish and dried at 40°C for 3 h to remove the acetonitrile, then moved to a vacuum oven to dry at 60°C for 12 h.

[0123] Characterization

[0124] Field emission scanning electron microscope (FESEM) and energy dispersive spectroscopy (EDS) measurements were performed on a 30-kV JEOL JSM-IT500HR operated at accelerating voltage of 5 kV. Selected area diffraction pattern (SAED) collection and Energy dispersive spectroscopy (EDS) were performed using an aberration corrected JEOL ARM200CF with a cold field emission gun operated at 200 kV, equipped with an Oxford X-max 100TLE windowless X-ray detector. XRD was performed on a Bruker D8 with a 20 range of 10° to 85° at 1600 W (40kV, 40mA). The resolution was 0.02° with time steps of 1.5 s. The thickness of the SPE was measured at several locations with a Rexbeti digital micrometer with a 0.001 mm resolution.

[0125] The XRD data for the MEO produced above is provided in Table 1.Table 1

[0126] Elemental analysis of the MEO was determined by ICP OES. The equipment used was an Optical Atomic Emission Spectrometer with Inductively Coupled Plasma (ICP OES, Radial) from Spectro, model Arcos. Digestion of the sample was performed by alkaline fusion with lithium tetraborate in muffle at 980°C, followed by dissolution with nitric acid at 100°C in a digester block. The experiment was performed in duplicate. Results in percent by mass (%) or parts per million (ppm); 1 % = 10,000 ppm (mg kg-1or mg L-1). The data is provided in Table 2.Table 2

[0127] Cell Assembly

[0128] The electrochemical properties of the SPEs were determined after assembly in a CR2032 coin cell in an argon filled glovebox. EIS tests were conducted on SS || SPE || SS cells (where SS refers to stainless steel) as seen in Fig. 1A. The cycling tests were performed on LFP || SPE || Li cell as seen in Fig. 1B with a cathode material composed of LiFePO4(LFP), Super P carbon black 99+% and polyvinylidene fluoride (PVDF) by weighed ratios of 70:15:15 and cast onto aluminum foil. N-methyl pyrrolidone (NMP) was used as the solvent. The active material loading of LFP was 1.57 mg cm-2. Lithium metal (thickness 0.25 mm) was used as the anode. The SPE was punched into 17 mm discs from the main casting and ranged in thickness from 153 - 247 pm depending on MEO filler amount. The SPE was used directly as the electrolyte and membrane in each cell. The voltage range during cycling was 2.5 - 4.2 V at a rate of 1C (1C = 160 mAh) and a temperature of 80°C. The LSV was performed on a Li || SPE || SS cell as seen in Fig. 1C. The over potential test was performed on a Li || SPE || Li cell as seen in Fig. 1D.

[0129] Electrochemical Measurements

[0130] All testing was performed on a BioLogic VMP3. Cyclic Voltammogram (CV) tests were conducted in a potential window of 2.5 - 4.2 V at 0.1 mVs-1and a temperature of 80°C. The ionicconductivity of the SPE was measured using electrochemical impedance spectroscopy (EIS) with a frequency range of 106Hz to 10'1Hz with a 10 mV potential amplitude. The cells were assembled using a 2032 coin cell, two stainless steel blocking electrodes and the SPE in an argon filled glovebox.

[0131] The charge / discharge tests were performed in the voltage range of 2.5 - 4.2 V at 10 (1C = 160 mAh) and a temperature of 80°C. The lithium ion transference number (t^) of the SPE was measured at 80°C using AC impedance and DC polarization in Li || SPE || Li symmetrical cells. The DC voltage (AV) was 10mV and the impedance was measured between 1MHz and 0.01 Hz with an oscillation voltage of 10 mV. The over potential of the SPE was measured at 80°C with a current of 20 pA cm-2and a 60 min charge / discharge cycle.28

[0132] Results and Discussion

[0133] A common method for making polymer electrolytes is to use the casting process. Polymer and MEO fillers were mixed together and then cast into a sample holder and dried. The casting process is described below in the Experimental Procedures section. The MEO fillers were synthesized using a ball milling and sintering technique, which was chosen based on the desired elements used for the MEO filler. The full process description can be found below in the Experimental Procedures section.

[0134] Structure of AITi Mg LiO MEO Powder

[0135] The morphology of the MEO filler and the various SPE were analyzed using SEM and TEM, as shown in Fig. 2A. The particles exhibited an irregularly shaped structure with an average particle size of 204 nm. X-ray diffraction (XRD) was utilized to characterize both the SPE and the MEO additive. The XRD pattern for the AITiMgLiO MEO powder can be seen in Fig. 2B, which revealed that the synthesized particles can be characterized as a cubic spinel crystal phase with a lattice constant of 8.11 ± 0.02 A.2930The corresponding selected area electron diffraction (SAED) pattern for the additive powder is depicted in Fig. 2C, which displayed the planes for 111 , 220, 311 , 400, 420, and 262 that were also found in the XRD results, confirming the spinel crystal structure of the MEO additive. However, additional peaks not attributed to the spinel crystal structure were present in the SAED and XRD pattern, representing areas of the MEO particles that did not coalesce into a single solid solution during synthesis. The mixing entropy appear to not be high enough to form a single solid solution under typical synthesis conditions used during particle synthesis and requires increased temperatures during the heat treatment process. Thelower entropy causes some elements to mix unevenly, resulting in added distortions to the crystal structure. The distortions can lead to additional peaks forming in the XRD pattern.2931The STEM- EDS map displayed in Fig. 2D demonstrated that Ti, Mg, and O were well-mixed, with areas of Al not uniformly mixed showing that Al did not fully coalesce into the spinel phase. The uneven mixing seen in the STEM-EDS map confirms the additional peaks found in the XRD spectrum.

[0136] The XRD pattern of SPE-0, SPE-MEO-10, and SPE-MEO-60 are shown in Fig. 3D. SPE- 0 has two main peaks located at 29 of 19.09° and 23.26° which appear in all SPE samples. These two peaks are the result of the PEO crystalline phases in the polymer.32There was no discernible difference in XRD pattern between the SPE-0 and SPE-MEO-10 SPE. SPE-MEO-60 had several of the higher intensity peaks found in the EO additive start to appear in the XRD pattern of the SPE. The appearance of MEO particle peaks in the XRD pattern of SPE-MEO-60 indicates the successful incorporation of the MEO additive into the polymer matrix. The presence of these peaks suggests that the MEO particles retained their crystal structure in the polymer and did not undergo significant chemical changes during the casting process.

[0137] Microscopy of PEO solid polymer electrolyte

[0138] The SPE are flexible and ranged in thickness from 153 - 247 pm. The morphology of the microstructure for SPE-0, SPE-MEO-10, and SPE-MEO-60 are shown in Fig. 3A, B, and C, respectively. SPE-0 exhibits a spherulitic structure due to the addition of the LiTFSI salt.33As MEO is added to the PEO, the spherulitic structure reduces in size for SPE-MEO-10 and completely disappear in SPE-MEO-60 specimens. These spherulites can be correlated to the crystalline phase in the PEO, and the decrease in their size suggest an increase in amorphous portion of PEO.34

[0139] Ionic conductivity of solid polymer electrolyte

[0140] Electrochemical impedance spectroscopy (EIS) was performed on all of the SPE to determine the bulk resistance of the membrane. EIS patterns for multiple test cells can be seen in Figs. 4A-4D (SPE-0), Figs. 5A-5D (SPE-AI2O3-10), Figs. 6A-6D (SPE-MEO-10), and Figs. 7A-7D (SPE-MEO-60) at temperatures ranging from 30 °C to 80 °C. The bulk resistance of each electrolyte decreases as the temperature increases and reaches a near-constant value around 50°C, close to the melting temperature (Tm) of the PEO. Above Tm, the PEO becomes more amorphous, and its crystallinity increases below Tm, leading to changes in bulk resistance. The bulk resistance (Rb) and Eq. 1 were used to calculate the ionic conductivities at varioustemperatures, where L (cm) represents the thickness of the SPE, S (cm2) represents the area of the stainless-steel electrode, and Rb(O) represents the bulk resistance of the electrolyte membrane, as measured by EIS.

[0141] Fig. 3F shows the plot of the ionic conductivities for SPE with varying MEO fillers. The ionic conductivity of SPE-0 is 4.65 x 10'6S cm-1at 30°C and reaches a maximum of 9.94 x 10'4S cm-1at 80°C. SPE-MEO-10 has an ionic conductivity of 2.00 x 10'6S cm'1at 30°C and a maximum of 8.39 x 10'4S cm-1at 80°C, while SPE-MEO-60 has an ionic conductivity of 7.73 x 10'7S cm-1at 30°C and a maximum of 3.55 x 10'4S cm-1at 80°C. The ionic conductivity of SPE-AI2O3-IO is 1.39 x 10-6S cm-1at 30°C and reaches a maximum of 6.78 x 10'4S cm-1at 80°C. The ionic conductivity in SPE-MEO-10 is lower than that found in SPE-0 across all temperatures, and as more filler is added, the ionic conductivity is further reduced. Several factors contribute to the overall ionic conductivity found in a polymer.

[0142] As shown in Fig. 3F, the ionic conductivities exhibit different slopes in the low- temperature regions (30°C - 50°C) compared to those in the high-temperature regions (60°C - 80°C). To analyze this difference, we calculated the activation energies for the SPE using Eq. 2, where A is the pre-exponential factor, k is the Boltzmann constant, o is the ionic conductivity, and Eais the activation energy for lithium-ion conduction.40

[0143] The activation energies are summarized in Table 3, showing values ranging from 61.32 - 70.67 kJ mol-1in the low-temperature region and 15.63 - 22.04 kJ mol'1in the high-temperature region. The difference in activation energies is attributed to the recrystallization of PEO from the amorphous state when it is cooled to the transition temperature of 60 °C.8This crystallization leads to slower lithium transport through the PEO explained by the higher activation energy values at 30-50°C.8In the 30-50°C region, the addition of 10wt% MEO did not change the activation energy indicating that the ionic conductivity is still governed by PEO.34However, the activation energy increased for SPE-MEO-60 specimens pointing to possible heterogeneous distribution of fillers in PEO that may cause agglomeration of the fillers. At high temperatures, all SPE specimensshowed a decrease in activation energy, which is expected in PEO materials due to the ease of segmental motions.Table 3

[0144] Electrochemical performance of solid polymer electrolyte

[0145] Lithium transference number

[0146] The calculated values for the lithium-ion transference number (t j) for SPE-0, SPE-MEO- 10, and SPE-MEO-60 are summarized in Table 4. These values were calculated using Eq. 3, where currents l0and lssrepresent the initial and steady state currents during DC polarization, and Roand Rssrepresent the electrode resistances before and after polarization, respectively41Li~ IO(AV—ISSRSS){'Table 4

[0147] As seen in Table 4, the values forinitially increase as more MEO is added, resulting in an increase infor SPE-MEO-10. The increase in transference number can be correlated to higher dissociation of Li ions from their anion compartments in LiTFSI salts due to the presence of multielement particles. It is expected that the presence of Al, Ti, and Mg cations in MEO results in stronger interactions with salt anions leading to more mobile Li ions. However, once the SPE reaches 60wt%, thedecreases to below thefound in SPE-0. This decrease inisattributed to the filler having a blocking effect, resulting in higher scattering of the Li ions moving across the SPE. The transference number has a large impact on the electrochemical performances of Li ion batteries.1According to simulations,that approaches unity results in Li dendrite growth that theoretically stops as Li metal can be reversibly plated and stripped in the electrolyte.42The improvement toin SPE-MEO-10 should slow down Li dendrite growth compared to SPE-0.

[0148] Linear sweep voltammetry

[0149] The electrochemical stability of the SPE is an important parameter to determine practical applications as an electrolyte in lithium-ion batteries. To determine the stability of the SPE, linear sweep voltammetry (LSV) was performed. As shown in Fig. 3E, both SPE-MEO-10 and SPE- MEO-60 are found to be more stable than SPE-0. There was no anodic current in SPE-MEO-10 until 6.18 V, and SPE-MEO-60 showed no current until 6.55 V. SPE-0 started showing current flow at 4.66 V. Above these voltages, the SPE will start to decompose due to oxidation reactions. The larger voltage window is attributed to the MEO additive of Al, Ti, and Mg, as such metal oxides are known to be good insulators due to high resistivity and high dielectric constants.43-46The higher stability voltage windows found in SPE-MEO-10 and SPE-MEO-60 indicate potential of MEO-polymer composites for use in high voltage lithium batteries.

[0150] Voltage Polarization

[0151] To further study the electrochemical stability of the SPE, the voltage polarization of the SPE was investigated. Fig. 8 shows the overpotential values with a current density of 20 pA cm-2. SPE-0 had an average over potential of -10.66 mV on the negative potential and 10.10 mV on the positive potential, with an absolute min of -12.1 mV and an absolute max of 11.6 mV. SPE- AI2O3-IO had an average over potential of -12.40 mV on the negative potential and 11.36 mV on the positive potential, with an absolute min of -17.5 mV and an absolute max of 15.1 mV. SPE- MEO-10 showed a lower average over potential of -8.80 mV on the negative potential and 7.97 mV on the positive potential with an absolute min of -9.35 mV and an absolute max of 8.45 mV. The lower overpotential values in SPE-MEO-10 indicates a higher ease of deposition / stripping from the foil surface for the SPE with the MEO fillers.28The increasing overpotential increasing with cycle number found in SPE-0 during the first 33 h and in SPE-AI2O3-IO during the first 14 h is an indication of a thick and growing interfacial layers due to uneven lithium plating that can be detrimental for further cycling.28SPE-AI2O3-IO shows a sharp increase in the overpotential in theinitial cycles and a higher overpotential overall, highlighting fast growing interfacial layers likely due to dendrite formation. SPE-MEO-10 shows a slower increasing overpotential with increasing cycle number indicating more uniform growth of the interfacial layer indicative of less Li dendritic behavior. The voltage polarization remained stable through 500 cycles and shows safe operation along with the ability to block lithium dendrite penetration over long cycles.47

[0152] Cycling performance of solid polymer electrolyte

[0153] The electrochemical properties of SPE composites were further studied by investigating the cycling characteristics during charge / discharge. Figs. 9A-9F show the charge-discharge profile and cycling performance of SPE-0, SPE-AI2O3-IO and SPE-MEO-10. The cycling performance of SPE-MEO-60 was not included due to initial characterization of the electrolyte which resulted in higher resistance values and lower ionic conductivity, lower transference number, and poorer morphology. The voltage profiles for selected cycles are shown in Fig. 9A, 9B and 9C. During the first 50 cycles, SPE-MEO-10 had a much smaller capacity loss than both SPE-0 and SPE-AI2O3-IO. SPE-AI2O3-IO showed a slight improvement in capacity loss over SPE- 0. In cycle 1 , SPE-0 had an initial capacity of 140.30 mAh g-1, which reduced to 123.12 mAh g-1in cycle 50, resulting in a reduction of 17.17 mAh g-1(-12.24%). The unary SPE-AI2O3-IO had an initial capacity of 144.25 mAh g-1in cycle 1 and reduced to 128.94 mAh g-1after 50 cycles, a reduction of 15.32 mAh g-1(-10.61%). The unary additive was a slight improvement over SPE-0 during the first 50 cycles. However, SPE-MEO-10 had an initial capacity of 126.67 mAh g-1in cycle 1 and reduced to 121.76 mAh g-1after 50 cycles, a reduction of only 4.91 mAh g-1(-3.88%). Fig. 10 highlights the capacity loss by cycling region and shows not only a lower decrease across all regions in SPE-MEO-10 but a substantial improvement in the first 50 cycles compared to SPE-0 and SPE-AI2O3-IO. The long-term cycling for SPE-0, SPE-AI2O3-IO and SPE-MEO-10 are shown in Fig. 9D, 9E, and 9F. SPE-MEO-10 had a lower initial capacity than SPE-0 and SPE-AI2O3-IO (126.67 vs 140.30 mAh g-1and 144.25 mAh g-1) due to the decrease in conductivity of the SPE, but it exhibited better long-term cycling performance than the other two SPE. At higher charging rates, the lower conductivity causes the cell to run into transport issues as ions cannot move fast enough through the electrolyte. The higher resistance values in the electrolyte, coupled with higher charging rates, result in higher ohmic losses, which cause higher voltage drops. The lower cutoff voltage is reached faster, resulting in a lower overall capacity. Similar phenomenon have been reported in other systems where there is a loss in capacity due to lower ionic conductivity at higher charging rates.48However, the MEO filler in SPE-MEO-10 had a positive effect on theoverall stability of the cells, causing less capacity loss per cycle than SPE-0 and SPE-AI2O3-IO. SPE-0 had a maximum capacity of 140.30 mAh g-1and a capacity of 94.66 mAh g-1after 500 cycles, resulting in a capacity retention of 64.47%. The unary electrolyte, SPE-AI2O3- , had a maximum capacity of 144.25 mAh g-1and a capacity of 61.53 mAh g-1after 500 cycles, resulting in a capacity retention of 42.65%. SPE-AI2O3-IO had a lower average Coulombic efficiency and more variability than both SPE-0 and SPE-MEO-10. In contrast, SPE-MEO-10 had a maximum capacity of 126.67 mAh g-1and a capacity of 99.68 mAh g-1after 500 cycles, resulting in a capacity retention of 78.69%. The MEO filler in SPE-MEO-10 resulted in a 14.2% increase in capacity retention and 5.03 mAh g-1increase in overall capacity over 500 cycles, demonstrating stable interfacial layers and better lithium plating due to the MEO filler. In addition, the Coulombic efficiency was not only higher in SPE-MEO-10 but was more stable over the 500 cycles compared to SPE-0 and SPE-AI2O3-10.

[0154] Morphology Changes in Cycled Cells

[0155] The differences in capacity degradation were studied further by observing the Li anode after cycling. SPE-0, SPE-MEO-10 and SPE-AI2O3-IO were cycled for 100 cycles to compare how the surface morphology changes during cycling. Figs. 11A-11H shows a comparison of the Li anode for different electrolytes. Fig. 11A and 11 E shows the surface morphology of a fresh Li anode that was not cycled. Here, you can observe a fairly rough and uneven surface before any cycling has occurred. Fig. 11B and 11 F shows the Li anode of a cell cycled with SPE-0. The Li anode shares a similar rough and uneven surface as the fresh Li surface but is thicker and more interconnected, representing uneven growth of the lithium morphology. Fig. 11C and 11G shows the Li anode of a cell cycled with SPE-AI2O3-IO. The surface is covered by a thick layer of growth. The morphology found in the fresh Li anode are no longer observable in SPE-AI2O3-IO and have become covered by the formed interfacial layer. The SPE-AI2O3-IO shows some evidence of uneven lithium plating explaining the resulting poor capacity retention. Fig. 11D and 11H shows the Li anode of a cell cycled with SPE-MEO-10. Here, a dense uniform lithium morphology is observed pointing to the ability of SPE-MEO-10 electrolytes to suppress the dendritic lithium. In a study with silica, these particles improved cycle life and was attributed to the formation of a smoother and denser layer as observed by SEM.49The MEO filler allows for a slower, more uniform interfacial layer to form and grow, reducing capacity degradation over time.

[0156] Mechanisms for reduced dendritic growth

[0157] The increase in cycling stability is attributed to the enhanced suppression of lithium dendrites achieved through increased mechanical stiffness of SPE-MEO-10 and also the presence of multielement particles in the electrolyte. Recent research on lithium dendrite growth indicates that even minor stresses and imperfections on a surface can initiate and propagate Li dendrite formation.50Thus, relying solely on the strategy of eliminating imperfections may not be practical for large-scale manufacturing of LIBs. High molecular weight polymers like PEO demonstrate thermodynamic stability with Li up to temperatures as high as 100 °C.51With minimal interfacial reaction between PEO and fresh Li, the primary factor limiting the cycle life of Li metal anodes is Li dendrite growth.1It has been demonstrated that PEO alone cannot effectively block dendrite growth, particularly at elevated temperatures when the strength of PEO significantly diminishes.1’52However, mechanical blocking is a viable method that can reduce lithium dendrite growth and improve cycle life.1Additionally, multielement materials exhibit synergistic effects enhancing the polymer’s electrochemical properties. The mechanism for improvement in lithium plating with multielement particles can be seen in Figs. 12A-D. In Fig. 12A, an uncycled Li anode with a SPE is shown. The Li anode surface has a relatively flat morphology before any cycling occurs. Fig. 12B. shows the case for SPE-0 when no MEO particles are used. The SPE is not mechanically strong enough to suppress the formation of the interfacial layer and also does not have high selectivity for mobile lithium or voltage stability as we see in the composite electrolyte cases, resulting in dendritic lithium morphology. Fig. 12C shows the case for SPE-AI2O3-W composites when AI2O3 fillers were used. The AI2O3 fillers are mechanically strong enough to suppress the dendritic growth, which causes different areas of the Li anode to grow at different rates until a uniform layer is formed. While AI2O3 particles are able to increase the mechanical properties of the SPE, the electrochemical properties of the SPE are negatively affected, making it incompetent to fully reduce uneven lithium deposition, resulting in the cycling capacity being greatly reduced. Fig. 12D shows the case for SPE-MEO-10 when a MEO particles are used. The increase of mechanical properties in SPE-MEO-10, along with the improvement in mobile lithium selectivity (transference number) and better stability under the electrochemical charge / discharge window, allows for a more uniform lithium plating and stripping behavior. The improvements to the lithium morphology result in improved capacity retention and longer life during cycling for SPE- MEO-10.

[0158] It should be emphasized that the above-described embodiments of the present disclosure are merely possible examples of implementations set forth for a clear understanding of the principles of the disclosure. Many variations and modifications may be made to the above-described embodiment(s) without departing substantially from the spirit and principles of the disclosure. All such modifications and variations are intended to be included herein within the scope of this disclosure and protected by the following claims.REFERENCES1. Xu W, Wang J, Ding F, Chen X, Nasybulin E, Zhang Y, et al. (2014). Lithium metal anodes for rechargeable batteries. Energy Environ Sci. 7, 513-37. 10.1039 / c3ee40795k2. Chen X, He W, Ding LX, Wang S, Wang H. (2019). Enhancing interfacial contact in all solid state batteries with a cathode-supported solid electrolyte membrane framework. Energy Environ Sci. 12, 938-44. 10.1039 / c8ee02617c3. Choudhury S, Stalin S, Vu D, Warren A, Deng Y, Biswal P, et al. 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Claims

CLAIMS1. A compound having the formula AITiXLiO, wherein X is Mg, Ni, Mn Cu, or any combination thereof.

2. The compound of claim 1, wherein X is Mg.

3. The compound of claim 1or 2, wherein the weight ratio of Al to Ti is from 1:1 to 3:1.

4. The compound of any one of claims 1-3, wherein the weight ratio of Al to X is from 1 :1 to 4:1.

5. The compound of any one of claims 1-4, wherein the weight ratio of Ti to X is from 1 :1 to 3:1.

6. The compound of any one of claims 1-5, wherein Al is from about 10 weight percent to about 30 weight percent of the compound.

7. The compound of any one of claims 1-6, wherein Ti is from about 10 weight percent to about 20 weight percent of the compound.

8. The compound of any one of claims 1-7, wherein X is from about 10 weight percent to about 20 weight percent of the compound.

9. The compound of any one of claims 1-8, wherein Li is from about 1 weight percent to about 10 weight percent of the compound.

10. The compound of claim 1, wherein the compound has the formula AlaTibXcLidOe, wherein a is from 0.15 to 0.25; b is from 0.10 to 0.15; c is from 0.05 to 0.10; d is from 0.005 to 0.01 ; and e is from 0.50 to 0.60, wherein the sum of a, b, c, d, and e is 1.0.

11. The compound of claim 1 , wherein X is Mg.

12. The compound of any one of claims 1-11 , wherein the compound has an average particle size of about 150 nm to about 250 nm.

13. The compound of any one of claims 1-12, wherein the compound has cubic spinel crystal phase.

14. The compound of any one of claims 1-13, wherein the compound has an X-ray powder diffraction pattern comprising peaks at 15.6° and 36.9° ± 0.2° 20 as measured by X-ray powder diffraction using an X-ray wavelength of 1.5418 A.

15. The compound of any one of claims 1-13, wherein the compound has an X-ray powder diffraction pattern comprising peaks at 15.6°, 36.9°, and 44.8° ± 0.2° 20 as measured by X-ray powder diffraction using an X-ray wavelength of 1.5418 A.

16. The compound of any one of claims 1-13, wherein the compound has an X-ray powder diffraction pattern comprising peaks at 15.6°, 36.9°, 44.8°, and 65.5° ± 0.2° 20 as measured by X-ray powder diffraction using an X-ray wavelength of 1.5418 A.

17. A compound produced by the method comprising(a) mixing in the solid state the following components: (i) AI2O3; (ii) TiO2; (iii) XO, wherein X is Mg, Ni, Mn Cu, or any combination thereof; and (iv) a lithium ion source to produce a first mixture, and(b) heating the first mixture at a temperature of about 800 °C to about 1 ,200 °C.

18. The compound of claim 17, wherein the components are mixed by mechanochemical milling.

19. A polymeric composition comprising a polymer, a lithium ion source, and the compound of any one of claims 1-18.

20. The composition of claim 19, wherein the polymer comprises a polyalkylene oxide homopolymer or copolymer.

21. The composition of claim 19, wherein the polymer comprises a polyethylene oxide, polypropylene oxide, or a combination thereof.

22. The composition of any one of claims 19-21 , wherein the polymer has an average molecular weight from 250 kDa to 1 ,500 kDa.

23. The composition of claim 19, wherein the polymer is polyethylene oxide having an average molecular weight from 250 kDa to 750 kDa.

24. The composition of any one of claims 19-23, wherein compound is from 5 weight % to about 75 weight percent of the composition.

25. The composition of any one of claims 19-23, wherein compound is from 5 weight % to about 15 weight percent of the composition.

26. The composition of any one of claims 19-25, wherein the lithium ion source comprises LiPFe, LiBF4, UCIO4, lithium bis(fluorosulfonyl)amide, lithium bis(trifluoromethane)sulfonylamide, lithium bis(oxalato) borate, LiAsFe, LiPF3(CF2CF3)3 , lithium triflate, lithium dodecyl sulfate, lithium bis(trifluoromethanesulfonyl)imide, lithium bis(pentafluoroethanesulfonyl)imide, lithium difluoro(ethanedioato)borate, lithium bis(monofluoromalonato)borate, lithium 4,5-dicyano-1 ,2,3-triazolate, lithium 4,5-dicyano- 2-trifluoromethylimidazole, lithium oxide, or any combination thereof.

27. The composition of any one of claims 19-26, wherein the composition has an X-ray powder diffraction pattern comprising peaks at 19.1° and 23.3° ± 0.2° 20 as measured by X-ray powder diffraction using an X-ray wavelength of 1.5418 A.

28. The composition of any one of claims 19-27, wherein the composition has an ionic conductivity of about 1.00 x 10’6S / cm to about 3.00 x 10'6S / cm at 30 °C.

29. The composition of any one of claims 19-28, wherein the composition has a lithium transference number of 0.40 to 0.50.

30. The composition of any one of claims 19-29, wherein the composition has an electrochemical stability of 6.0 V to 7.0 V.

31. The composition of any one of claims 19-30, wherein the composition after 50 cycles has a capacity retention of at least 95% of the same composition prior to cycling.

32. The composition of any one of claims 19-30, wherein the composition after 500 cycles has a capacity retention of at least 75% of the same composition prior to cycling.

33. A lithium battery comprising a positive electrode, a negative electrode, and the polymeric composition of any one of claims 19-32, wherein the polymeric composition is positioned between the positive electrode and the negative electrode.

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