Electrolyte and lithium ion batteries made therewith

Abstract

A battery having a cathode comprised of a disordered rocksalt and a localized high concentration electrolyte having a halogenated phosphorous additive has improved cycle life. The cycle life may be increased by 5%, 10% or 20% or more when using the halogenated phosphorous additive such as a phosphate, phosphonate or phosphite. Halogenated phosphorous additives may have hydrocarbyl groups further substituted with a heteroatom such as a double bonded oxygen (e.g., ester, carbonate, keto, and aldehyde group).

Description

Atty. Doc. No. WCAT-198-A-WO ELECTROLYTE AND LITHIUM ION BATTERIES MADE THEREWITH Field

[0001] This invention is directed to lithium ion batteries and in particular an electrolyte useful for lithium ion batteries having a cathode comprised of disordered rocksalt. Background

[0002] Lithium metal oxides have been used to formulate cathode materials for lithium ion batteries. The cathodes are derived from a few basic crystallographic structure types, such as spinels, olivines, and layered oxide structures. The layered oxide structures have included lithium- excess type structures, where additional lithium is present in the structure.

[0003] Recently, attention has been focused on disordered rocksalt structures, such as those formed from particular lithium metal oxides. Compounds represented by the formula: xLi3NbO4•(1-x)LiMO2 (1) where M is a multivalent cation, have been shown to be a promising class of transition metal oxides for use as cathodes in lithium ion batteries. The compounds of formula (1) are considered a disordered rocksalt in which a random atomic arrangement of lithium and transition metal ions are packed in a closely-packed cubic structure. These disordered rocksalt compositions offer the ability to contain up to 3 lithium atoms per formula unit, which is more than the conventional lithium-excess layered materials. Formula (1) can be transformed and represented as LixMyNzOw.

[0004] The disordered rocksalt structure is an attractive cathode material for next generation lithium ion batteries due to a greater specific energy density (e.g., a higher theoretical energy density) than state-of-the-art cathode materials, such as layered lithium metal oxide and spinel structures. For example, certain disordered rocksalt structure materials have a theoretical gravimetric energy density of about 1120 Wh / kg, while a LiMn2O4 active material has a theoretical gravimetric energy density of about 492 Wh / kg and a LiMn1.5Ni0.5O4has a theoretical gravimetric energy density of about 691 Wh / kg. This energy density is especially appealing when lower cost raw materials are used as components in the disordered rocksalt structure, such as manganese, which may be in combination with other transition metals. As such, the disordered rocksalt (DR) materials can achieve relatively high energy density with relatively low material cost. In order to achieve comparable energy density, known cathode materials require higher-cost raw materials, such as cobalt or nickel. 14879-2997-1135, v. 4Atty. Doc. No. WCAT-198-A-WO

[0005] Unfortunately, these DR materials require the particle size to be in the submicrometer range due to the low Li diffusivity of these materials. This has caused these DR materials to suffer poor capacity and voltage retention issues, largely originating from the poorly controlled, heavily- pulverized nanoparticle morphology introduced upon preparing the DR materials. The pulverized particle morphology of Mn-DR tends to accelerate the electrolyte decomposition and Mn- dissolution to the electrolyte, leading to the short cycle life of the cathode materials. Also, the pulverized particle morphology may lead to low electrode density decreasing the volumetric energy density of the Mn-DR cathode film.

[0006] To remedy some of the shortcoming of high salt concentration electrolytes, a diluent solvent (diluent or diluting solvent) has been added to the high salt concentration electrolyte to form a localized high salt concentration electrolyte (LHCE) that has desirable viscosity while retaining some of the performance improvements of high concentration electrolytes (see, for example, US Pat Nos.11,094,966 and 10,367,232). The diluent is soluble in the solvating solvent, but the salt is less soluble in the diluent than the solvating solvent.

[0007] Localized high concentration electrolytes (LHCE) contain a lithium salt (e.g., lithium bis(fluorosulfonyl)imide, LiFSI), solvating solvent (e.g., dimethyl carbonate, DMC), as well as diluents such as 1,1,2,2-tetrafluoroethyl 2,2,3,3-tetrafluoropropyl ether (TTE). In LHCEs, diluent solvents do not disrupt the solvent structure of the primary solvent(s) around the ions from the salt, but largely reduces the viscosity of the electrolyte. Due to the highly solvated structure, the Li salt is able to be reduced and form a LiF rich solid electrolyte interphase (SEI), that has improved lithium ion battery performance. However, further improvements are desirable, particularly lithium ion batteries having cathodes comprised of a disordered rocksalt.

[0008] Accordingly, it would be desirable to provide a battery utilizing a high voltage cathode such as those comprised of a disordered rocksalt with improved performance such as longer cycle life and desirable power delivery. Summary

[0009] A battery having a high voltage cathode such as those comprised of a disordered rocksalt has been discovered that improves cycle life without adversely affecting desirable characteristics such as power delivery. It has been discovered that an electrolyte comprised a solvating solvent, a diluent solvent, a lithium salt and a halogenated phosphorous additive may 24879-2997-1135, v. 4Atty. Doc. No. WCAT-198-A-WO improve cycle life without deleteriously affecting other properties of the battery. This halogenated phosphorous additive may improve the cycle life of the battery by 10% or more. The additive is effective at low concentrations in the electrolyte. Illustratively the additive is present in amount from about 0.02% to 5% by weight of the electrolyte.

[0010] An illustration is a battery comprising a cathode comprised of a disordered rocksalt, anode, separator and localized high concentration electrolyte (LHCE) comprised of a solvating solvent, a diluent solvent, a lithium salt and a halogenated phosphorous additive in an additive amount of 0.02% to 5% by weight of the electrolyte. A- LHCE is a solution comprised of a solvating solvent, diluent and a dissolved lithium salt, the lithium salt generally being at least 5 times more soluble in the solvating solvent than the diluent. In an embodiment, the lithium salt is comprised of lithium bis(fluorosulfonyl)imide (LiFSI) and / or Lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) and in particular in the absence of any other lithium salts. Brief Description of the Drawings

[0011] Figure 1 displays the cycling behavior of batteries of and not of this invention.

[0012] Figure 2 displays the cycling behavior of batteries of and not of this invention.

[0013] Figure 3 displays the cycling behavior of batteries of and not of this invention.

[0014] Figure 4 displays the cycling behavior of batteries of and not of this invention. Detailed Description

[0015] Definitions of specific functional groups and chemical terms are described in more detail below. For purposes of this invention, the chemical elements are identified in accordance with the Periodic Table of the Elements, CAS version, Handbook of Chemistry and Physics, 75thEd., inside cover, and specific functional groups are generally defined as described therein. Additionally, general principles of organic chemistry, as well as specific functional moieties and reactivity, are described in Organic Chemistry, Thomas Sorrell, University Science Books, Sausalito, 1999; Smith and March March’s Advanced Organic Chemistry, 5thEdition, John Wiley & Sons, Inc., New York, 2001; Larock, Comprehensive Organic Transformations, VCH Publishers, Inc., New York, 1989; Carruthers, Some Modern Methods of Organic Synthesis, 3rdEdition, Cambridge University Press, Cambridge, 1987; the entire contents of each of which are incorporated herein by reference. 34879-2997-1135, v. 4Atty. Doc. No. WCAT-198-A-WO

[0016] If not otherwise specified any characteristic or property may be determined by standard laboratory practices for determining such properties or characteristics. The boiling temperature may be determined by ASTM D86 if not generally available in the literature. “Solubility” may be determined by the ‘shake flask’ method based on the guidelines provided by OECD, Paris, 1981, Test Guideline 107, Decision of the Council C(81) 30 final. “Viscosity” may be determined by ATSM D445 if not generally available in the literature.

[0017] The electrolyte comprises a solution comprised of a solvating solvent, a diluent, a lithium salt and a phosphorus additive in an amount of 0.02% to 5% by weight of the electrolyte. The phosphorus additive is present in an amount of 0.02% to 5% by weight of the electrolyte with the amount desirably being from 0.05%, 0.2%, or 0.5% to 4%, 3%, or 2%. Solution is understood to be a liquid herein where each of the components of the solution are intermixed on a molecular level.

[0018] The electrolyte is a solution that is comprised of a halogenated phosphorous additive. The phosphorous additive is any organic compound (not a salt) comprised of a phosphate, phosphonate or phosphite that has one or more halogens (1 to 20, 15, 12 or 10 halogens) that is solubilized in the electrolyte and improves the cycling performance of lithium ion batteries having a cathode comprised of a disordered rocksalt. Typically, the halogenated phosphorous additive is a small molecule having a molecular weight of most about 1000 g / mole. Illustratively, the phosphorous additive may be represented by one of the following: O R"where R, R’ and R” are the same or different and each is independently a halogen or substituted hydrocarbyl group having 1 to 12 carbons so long R, R’ and R” is substituted with at least one halogen if none of them is the halogen and R is bonded to the P with a C or halogen when R is directly bonded to P. Hydrocarbyl is an organic group containing one more carbon atom backbones and hydrogen atoms that may be substituted or unsubstituted. The hydrocarbyl may be linear, branched or cyclic (with it being understood that cyclic structures may be in combination 44879-2997-1135, v. 4Atty. Doc. No. WCAT-198-A-WO with linear or branched structures). The hydrocarbyl group may be aromatic, aliphatic or combination thereof. The hydrocarbyl group may be unsubstituted or substituted so long as there is at least one halogen in the halogenated phosphorous additive. The hydrocarbyl group may be substituted with 1 or 2 to any useful amount of heteroatoms such 20, 15, 10 or 5 heteroatoms with it being preferred to have from 1, 2, or 5 to 10 or 20 heteroatoms (e.g., Si, S, N, O, F and Cl). The heteroatoms may be any of those commonly found in organic compounds such as halogens (e.g., Cl and F) and particularly an O in addition to any halogens present in the substituted hydrocarbyl group.

[0019] Illustratively, it may be particularly useful for at least one of R and R’ and R” to be different with at least one of these being a hydrocarbyl group (i.e., the other being a halogen such as F or Cl). For example, R is a halogen and R’ and R” are hydrocarbyl groups including, for example, ones that are substituted or unsubstituted as described above, a substituted or unsubstituted aromatic group, an aliphatic substituted group and in particular ones that are branched or linear. The aliphatic group may be comprised of alkane, alkene and alkyne bonded carbons. Each of R, R’ and R” may be the hydrocarbyl group with at least one being substituted with a halogen. In an illustration each of R, R’ and R” are halogen substituted alkyl groups of 1 or 2 carbons to 12, 8, or 6 carbons.

[0020] In a further particularly useful illustration, the hydrocarbyl group is comprised of the halogen and at least one oxygen that is not bonded to the P of the phosphate, phosphonate or phosphite. That is, at least one, 2 or all of R, R’ and R” is substituted with halogen and oxygen not bonded to the P and preferably such oxygen is a double bonded oxygen such as found in a keto, ester, aldehyde or ester group.

[0021] Exemplary halogenated phosphorous additives include those comprised of one or more of the following: tris(2,2,2-trifluoroethyl) phosphate; bis(2,2,2-trifluoroethyl) methylphosphonate; diethyl (difluoromethyl)phosphonate; triethyl 2-fluoro-2-phosphonoacetate; tris(1,1,1,3,3,3- hexafluoro-2-propyl) phosphite, Tris(2,2,3,3-tetrafluoropropyl)phosphate, Tris(1,1,1,3,3,3- hexafluoro-2-propyl) Phosphate, Bis(2,2,2-trifluoroethyl)(methoxycarbonylmethyl) phosphonate, Ethyl 2-(bis(2,2,2-trifluoroethoxy)phosphoryl)acetate, 2-(2,2,2-Trifluoroethoxy)-1,3,2- dioxaphospholane 2-Oxide, Lithium difluorobis(oxalato)phosphate, and tris(2,2,2-trifluoroethyl) phosphite. 54879-2997-1135, v. 4Atty. Doc. No. WCAT-198-A-WO

[0022] The battery is comprised of a localized high concentration electrolyte (LHCE) comprised of a solvating solvent and a diluent solvent (diluent) and lithium salt such as those known in the art. The LHCE is comprised of a diluent solvent (diluent) that is soluble in the solvating solvent at the concentrations used, but does not solubilize the salt as well as the solvent to form a localized high concentration electrolyte (LHCE). Illustratively, the LHCE has solvating solvent, diluent and a dissolved lithium salt, the lithium salt typically being at least 2, 3 or 5 times more soluble in the solvating solvent than the diluent.

[0023] The LHCE may include a combination of diluents with different substitutions. For examples, a combination of diluents containing linear alkyl groups, branched alkyl groups, or both may provide for a different miscible molar ratio with the solvating solvent while achieving desirable discharge capacity and capacity retention.

[0024] The LHCE may include any number of different diluents sufficient to be miscible with the solvating solvent and / or adjust the viscosity of the electrolyte. For example, the electrolyte may include one or more, two or more, three or more, four or more, or a plurality of diluents.

[0025] The diluent may include one or more fluorinated ethers. The fluorinated ethers may be any compound that includes a combination of ether groups, fluorine atoms, and carbon atoms that are fully saturated with hydrogen.

[0026] Examples of fluorinated ethers may include one or more of 1,1,2,2-tetrafluoroethyl 2,2,3,3-tetrafluoropropyl ether (TTE); bis(2,2,2-trifluoroethyl) ether (BTFE), hexafluoroisopropyl methyl ether (HFPME); 1,1,2,2-tetrafluoroethyl ethyl ether (TFEEE); 1H,1H,5H-octafluoropentyl 1,1,2,2,-tetrafluoroethyl ether (OFPTFEE); 1,1,2,2-tetrafluoroethyl ether, 1,2-(1,1,2,2,- tetrafluoroethoxy) ethane (TFEE); 1,3-(1,1,2,2-Tetrafluoroethoxy)propane (TFEP), 1,1,2,3,3,3- hexafluoro propyl 2,2,2-trifluoroethyl ether (HFPTFEE); n-butyl 1,1,2,2-tetrafluoroethyl ether (BTFEE); 1H,1H,2’H,3H-decafluoro dipropyl ether (DFDPE); 1,1,2,3,3,3-hexafluoropropyl ethyl ether (HFPEE); 1,1,1-trifluoro-2-[1-(2,2,2-trifluoroethoxy)ethoxy] ethane (TTFEEE); 1H,1H,2’H-perfluorodipropyl ether (PFDPE); 1,1,2,2-tetrafluoroethyl isobutyl ether (TFEBE); 1,1,1,2,2,3,4,5,5,5-decafluro-2-methoxy-4-(trifluoromethyl)pentane; 1-(ethoxy)nonafluorobutane having a mixture of n- and iso-butyl isomers; 2-(trifluoromethyl)-3-ethoxydodecafluorohexane; 3- methoxyperfluoro(2-methylpentane); heptafluoropropyl 1,2,2,2-tetrafluoroethyl ether; 1,1,2,2- tetrafluoroethyl-2,2,2-trifluoroethyl ether (TFTFE); methoxynonafluorobutane (MOFB); 64879-2997-1135, v. 4Atty. Doc. No. WCAT-198-A-WO ethoxynonafluorobutane (EOFB); tris(2,2,2-trifluroethyl)orthoformate; di(2,2,2-trifluroethyl) carbonate; or any combination thereof.

[0027] The solvating solvent may be any solvent or combination of solvents that are miscible in the diluent and / or can dissolve the lithium salt with or without the presence of the diluent. The electrolyte may include any number of solvating solvents sufficient to form desirable solvation around cation and / or anion of the lithium salt. For example, the electrolyte may include one or more, two or more, three or more, four or more, or a plurality of solvating salts. The solubility of the salts in the solvating solvent and / or diluent may be essentially the same and or different. It may be desirable, for example, to have one salt that has a greater solubility (e.g., 5%, 10% or 20% more soluble than the other salts) in the diluent, which may be desirable in forming an advantageous SEI layer. In some examples, the solvating solvent may include one or more of dialkoxy alkanes, dialkyl glycol ethers, disubstituted esters, disubstituted carbonates, trisubstituted phosphates, disubstituted sulfones, tetrasubstituted silanes, or any combination thereof.

[0028] Dialkoxy alkanes may include a pair of alkyl ethers bound by a C1-12 alkane group that may be branched or linear. For example, dialkoxy alkanes may include one or more of dimethoxy ethane (DME), 1,2-Diethoxyethane (DEE), 1,2-dimethoxypropane (DMP), The dialkoxy alkane may have the following structure: where each R1 may independentlythat may be linear or branched, or any combination thereof where R2 may comprise a C1-12 alkyl group that may be linear or branched, or any combination thereof where n is an integer between 1 and 5. In some embodiments the R1 and R2 may be substituted with a halogen such as fluorine or chlorine.

[0029] Dialkyl glycol ethers may include a series of three ether groups separated by alkyl chains that may be linear or branched. Example of dialkyl glycol ethers may include one or more of 1,2-diethylene glycol isopropyl methyl ether (DEGIM), diethylene glycol butyl methyl ether (DEGBM), or any combination thereof. The dialkyl glycol may have the following structure:4879-2997-1135, v. 4Atty. Doc. No. WCAT-198-A-WO where each R1may independently comprise a C1-12alkyl group that may be linear or branched, or any combination thereof. where each R2 may independently comprise a C1-12 alkyl group that may be linear or branched, or any combination thereof. where each n is an integer between 1 and 5.

[0030] Disubstituted esters may include an ester that is substituted at the carbon atom of the carbonyl or the oxygen atom of the hydroxyl group by one or more groups including hydrogen, C1-12 alkyl, C1-12 aryl, or any combination thereof. Examples of disubstituted esters may include one or more of ethyl difluoroacetate, ethyl propionate, or any combination thereof. The disubstituted ester may have the following structure: where each R1may independentlyatom, a C1-12alkyl group that may be linear or branched, a hetero-alkyl group that may be linear or branched, or any combination thereof. Both R1in combination may form a cyclic alkyl ring that may optionally include one or more hetero atoms.

[0031] Disubstituted carbonates may be substituted independently at each of the carbon atoms. Disubstituted carbonates may include dimethyl carbonate, diethyl carbonate, ethyl methyl carbonate, fluoroethylene carbonate, or any combination thereof. The disubstituted carbonate may have the following structure: where each R1maya C1-12alkyl group that may be linear or branched, a hetero-alkyl group that may be linear or branched, or any combination thereof. Both R1 in combination may form a cyclic alkyl ring that may optionally include one or more hetero atoms.

[0032] Trisubstituted phosphates may be substituted at each of the single bonded oxygen atoms. Trisubstituted phosphates may include trimethyl phosphate, triethyl phosphate, or any combination thereof. The trisubstituted phosphates may have the following structure: 84879-2997-1135, v. 4Atty. Doc. No. WCAT-198-A-WO where each R1may independently atom, a C1-12alkyl group that may belinear or branched, a hetero atom, a group, or any combination thereof. where each R2may independently comprise a hydrogen atom, C1-12alkyl group that may be linear or branched, or any combination thereof.

[0033] Disubstituted sulfones may be substituted at the sulfur atom by one or more groups including hydrogen, C1-12 alkyl, C1-12 aryl, or any combination thereof. Disubstituted sulfones may include sulfolane, methyl ethyl sulfone, methyl isopropyl sulfone, or any combination thereof. The disubstituted sulfones may have the following structure: O O where each R4may independentlyatom, an unsubstituted C1-12alkyl group that may be linear or branched. Both R4in combination may form an unsubstituted cyclic alkyl ring.

[0034] Tetrasubstituted silanes may be substituted at the silicon atom and / or each oxygen atom. Tetrasubstituted silanes may include triethyoxymethyl silane, trimethoxymethylsilane, or any combination thereof. The tetrasubstituted silanes may have the following structure: where each R3may independentlyatom, a C1-12alkyl group that may be linear or branched, a hetero atom, a hetero-alkyl group, C1-12 alkoxy group that may be linear or branched, a hetero atom, a hetero-alkyl group, or any combination thereof. Further illustrations of suitable solvents and diluents are described in U.S. Pat. No. 10,367,232 and copending U.S. Provisional Application 63 / 435,662 incorporated herein by reference. 94879-2997-1135, v. 4Atty. Doc. No. WCAT-198-A-WO

[0035] The lithium salt may be any suitable lithium salt such as those known in the art. Typically, the lithium salt may have a solubility in the solvating solvent of about 1 M or more, about 3 M or more, or about 5 M or more. The lithium salt may have a solubility in the solvating solvent of about 20 M or less, about 15 M or less, or about 10 M or less. The lithium salt may be present in a concentration of about 3.5 M or less, about 2.0 M or less, or about 1.5 M or less. The lithium salt and combination of diluent / solvating solvent may be present in a molar ratio of about 1:2 or more, 1:2.6 or more, or 1:3.2 or more. The lithium salt and combination of diluent / solvating solvent may be present in a molar ratio of about 1:6 or less, about 1:5 or less, or about 1:4.

[0036] The lithium salt besides the may include one or more of lithium bis(fluorosulfonyl)imide (LiFSI), lithium (oxalato)borate (LiBOB), lithium bis(pentafluoroethylsulfonyl)imide (Li- BETI), lithium tetrafluoroborate (LiBF4), lithium trifluoromethanesulfonate (LiTriflate), lithium hexafluoroarsenate (LiAsF6), and lithium hexafluoro- phosphate (LiPF6), lithium nitrate (LiNO3), LiN(SO2CF3)2, LiClO4, lithium difluoro oxalato borate anion (LiDFOB), LiI, LiBr, LiCl, LiOH, LiSO4. Preferably a majority (greater than 50%) by mole of the lithium salt is LiFSI, with it generally being desirable for the LiFSI to comprise at least 75%, 90% or essentially all of the lithium salt in the electrolyte.

[0037] Exemplary LHCE combinations may include a lithium salt comprising lithium bis(fluorosulfonyl)imide (LiFSI), a solvating solvent comprising dimethoxyethane (DME), 1,2- diethoxyethane (DEE), dimethylcarbonate (DMC) , 1 , 3 - dioxolane (DOL) , ethyl methyl carbonate (EMC), diethyl carbonate (DEC) , dimethyl sulfoxide (DMSO) , ethyl vinyl sulfone (EVS) , tetram-ethylene sulfone (TMS) , ethyl methyl sulfone (EMS), ethylene carbonate (EC) , vinylene carbonate (VC), fluoroethylene carbonate (FEC), 4 -vinyl-1,3–dioxolan-2-one, dimethyl sulfone, methyl butyrate, ethyl propionate, trimethyl phosphate, triethyl phosphate, gamma- butyrolactone, 4-methylene-1,3-dioxolan-2-one, methylene ethylene carbonate (MEC) , 4,5- dimethylene-1,3-dioxolan-2-one , allyl ether , triallyl amine , triallyl cyanurate , triallyl isocyanurate or any combination thereof (the salt being present at a molar ratio of salt / solvating solvent of about 0.7 to 1.5) and a diluent comprising 1,1,2,2-tetrafluoroethyl-2,2,2,3- tetrafluoropropyl ether (TTE), bis(2,2,2-trifluoroethyl) ether (BTFE), 1,1,2,2-tetrafluoroethyl ether, 1,2-(1,1,2,2,-tetrafluoroethoxy) ethane (TFEE); 1,3-(1,1,2,2-Tetrafluoroethoxy)propane (TFEP), 1,1,2,2,-tetrafluoroethyl-2,2,2-trifluoroethyl ether (TFTFE), methoxynonafluorobutane ( MOFB ) , ethoxynonafluorobutane ( EOFB ) , or any combination thereof. 104879-2997-1135, v. 4Atty. Doc. No. WCAT-198-A-WO

[0038] Particular useful LHCEs are comprised of the following combinations: a lithium bis(fluorosulfonyl)imide (LiFSI), dimethyl carbonate (DMC), 1,1,2,2-tetrafluoroethyl 2,2,3,3- tetrafluoropropyl ether (TTE) combination; LiFSI, DMC, 1,2-(1,1,2,2-Tetrafluoroethoxy)ethane (TFEE) combination; LiFSI, DMC, 1H,1H,5H-octafluoropentyl 1,1,2,2,-tetrafluoroethyl ether (OFPTFEE) combination; LiFSI, DMC, 1,3-(1,1,2,2-Tetrafluoroethoxy)propane (TFEP) combination; LiFSI, DMC, 1H,1H,2’H,3H-decafluoro dipropyl ether (DFDPE) combination; LiFSI, ethyl methyl carbonate (EMC), TTE combination; LiFSI, EMC, TFEE combination; LiFSI, EMC, OFPTFEE combination; LiFSI, EMC, TFEP combination; LiFSI, EMC, DFDPE combination. The molar ratios of these may be (salt:solvating solvent:diluent) 1 ± 0.2:2 ± 1:3 ± 2.

[0039] The cathode of the battery is comprised of a disordered rocksalt. Generally, the cathode is comprised of a current collector, which may be a sheet or foil of a transition metal as described for the anode coated with an anode intercalating material (one capable of intercalating Li). Typically, the cathode material (powder) is coated on the current collector using a binder and electrically conductive materials. The binder may be any suitable such as those known in the art and may include, for example, carboxy methyl cellulose (CMC), styrene-butadiene rubber (SBR), polyvinylidene fluoride (PVDF), poly-tetrafluoroethylene (PTFE), or a mixture of two or more thereof. Desirably, the cathode is comprised of PVDF. The electrically conducting additive may be any suitable such as graphite, carbon black, carbon nanotubes, graphene and carbon fiber. The amount of other cathode components may be any suitable amount, but generally is at most about 20% or 10% by weight to about 0.1%, 0.5% or 1% by weight of the cathode (i.e., cathode material and other cathode components not including the current collector).

[0040] The cathode is comprised of a disordered rocksalt (DR) powder. The DR may be any disordered rocksalt composition useful to make a battery. Exemplary DR composition for the DR powder may be a DR comprising one having a formula: LixM’yMzO2-(a+b)Fa Zb where 1.0<x<1.75; 0≤y<0.55; 0.1<z<1; 0≤(a+b)<0.7; (b≥0) M’ is one or more of Ti, Ta, Zr, W, Nb, and Mo; M is one or more of Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Al, Zr, Y, Mo, Ru, Rh, Sn, Bi and Sb; Z is one or more of P, N and S. Further dopants may be included such as those substituting for Li such as Na and Mg, which may be at any useful amount, but generally are at most about 114879-2997-1135, v. 4Atty. Doc. No. WCAT-198-A-WO 10% or 5% to 0.01% by mole of the lithium and such dopants present in the DR. In an embodiment, M' is one of Ti, Ta, Zr, W Nb and Mo.

[0041] The amount of F and Z may be a majority or minority of the anion (i.e., O, F and one or more of P, S and N). Illustratively (a+b) is 0.05 to 1.5, 1, 0.95, 0.8, 0.65, 0.5. It may be desirable for a to be 0.05 to 0.25. Z may be any combination of P, N and S, or may be just one of them. The ratio between P, N and S when two or more are present may be any useful ratio depending on the attributes sought. For example, it may be desirable to have S present when a reduced redox potential is desired. It may also be desirable for S to be the majority of the P, S and N present in the composition.

[0042] The composition may have any desirable Li of 1 or above, but it may be desirable for Li as represented by x to be at least 1.1, 1.15, 1.2 to 1.65, 1.5 or 1.4.

[0043] The cation of the composition may be the metals described, but desirably, at least one of the metals as represented by M is comprised of one or more of Ti, Mn, Fe, Co,V, Cr, Ni and Cu. It may be desirable for M to be comprised of Ti and Mn. The composition may illustratively be one where M’ is comprised of Nb. When Nb is present, it may desirable for M to be comprised of Mn. Illustratively, M’ may be Nb and M may be Mn. When Nb and Mn are present with or without other metals, they may be present in a ratio of Mn / Nb of 1 or 2 to 200, 150, 100, 75, 50, 25 or 10 by mole.

[0044] The battery may have any suitable anode such as those known in the art including, for example, an anode absent a lithium intercalation material or a LMB. That is the anode in an anode- less battery is essentially a metal or electrically conductive material that does not intercalate lithium ions and preferably essentially does not alloy with Li at battery operating conditions. Exemplary materials include those suitable as current collectors such as a transition metal or alloy with copper, nickel and alloys of each being illustrative. In some embodiments, the anode may be comprised of an electrically conductive carbon. Electrically conductive carbons are as defined above and an illustration of such a carbon may be carbon black such as those available from Timcal under the tradename SUPER P. Preferably, the anode is a transition metal current collector. It is recognized upon the initial charging of the battery (oxidation of the cathode), lithium ions from the oxidation of the cathode coats the anode (e.g., transition metal / electrically conductive carbon current collector / sheet with lithium). When an electrically conductive carbon is present, typically 124879-2997-1135, v. 4Atty. Doc. No. WCAT-198-A-WO it is present as a coating on the transition metal current anode sheet or foil including a binder such as described herein and as described in U.S. Pat. No.9,172,085 incorporated herein by reference.

[0045] The battery may be a so-called lithium metal battery (LMB), wherein the anode is comprised of lithium metal or lithium metal alloy prior to the initial charging of the battery. The lithium metal may be present in any suitable amount and typically is present as a thin layer upon a transition metal current collector such as described above for the anode-less battery (1 or 5 micrometers to 50, 30 or 20 micrometers thick layer). The LMB likewise is free of an intercalation material, but may be comprised of other components as described for the anode-less battery.

[0046] Desirably, the anode is one that is comprised of a material that intercalates Li such as those known in the art (e.g., graphitic carbon and lithium titanate). The anode may include any material sufficient to function as an anode with the selected cathode and localized high concentration electrolyte. The anode may include one or more of graphite, lithium, lithium alloy, silicon, a silicon alloy, or any combination thereof. Where the anode is a lithium alloy or lithium metal, the electrolyte may be formulated such that formation of additional lithium surface area or lithium dendrites is reduced as the battery is cycled. Examples of suitable anode materials may include conventional anode materials used in lithium ion batteries, such as lithium, graphite (“LixC6”), and other carbon, silicon, or oxide-based anode materials.

[0047] In some examples, the anode may be graphite. Graphitic carbon may be any carbon capable of intercalating lithium with it being understood that carbons exhibiting short range order, but limited long range order that appear amorphous by X-ray diffraction may be used. The graphitic carbon, illustratively, may be synthetic or natural graphite having sufficient purity for use in lithium ion batteries, which typically requires a purity of at least about 99.5%, 99.9 or 99.95%. Illustratively, the graphitic carbon may be a spherical graphite, with it being understood that such graphite is not perfectly spherical but may be ovoid in nature, but are not flakes. The spherical graphite, generally, has a high purity such as at least 99.95% pure, but may also be comprised of a small amount of oxides such as silica, titania and zirconia or other materials capable of intercalating lithium but these are present in an amount of less than 5% or 1% by volume of the cathode. The spherical graphite may be from artificial graphite or purified natural graphite. Examples of useful spherical graphites are described in U.S. Pat. Pub.2016 / 0141603 and U.S. Pat. No 9,276,257, each incorporated herein by reference. Examples of suitable commercially 134879-2997-1135, v. 4Atty. Doc. No. WCAT-198-A-WO available spherical graphites include those available from Syrah Resources, Magnis Resources, Northern Graphite, Focus Graphite and Graphite One.

[0048] The battery is comprised of separator, which may any suitable separator such as those known in the art. Illustratively, the separator may have one or more layers that may be bonded together. Examples of suitable separators includes a polyimide, polyolefin (such as polypropylene), polyethylene terephthalate, ceramic-coated polyolefin, cellulose, or a mixture of two or more thereof. Such materials may be in the form of microfibers or nanofibers. The separator may include a combination of microfibers and nanofibers. In certain embodiments, the separator includes polyethylene terephthalate microfibers and cellulose nanofibers.

[0049] A separator having multiple layers may be used, each of which may have differing melting points. However, one of these layers may have a melting point lower than the other layer and may serve the purpose of a shutdown separator. For example, an inner layer of a separator may have a melting point of approximately 130° C. and a layer that may have a melting point of approximately 160°C. In this illustration, the inner layer would melt at a temperature of about 130° C, preventing ion flow in the battery but maintaining physical separation between the anode and cathode to prevent shorting. An example of a useful material having a melting point of approximately 130° C is high density polyethylene or ultra high molecular weight polyethylene. Examples of useful materials that have a melting point of >200° C include polyimide, polyethylene terephthalate, cellulose, aramid fibers, ceramics, and combinations thereof. In certain embodiments, the multiple separator layers with different melting points may be laminated together to form a single multi-layer composite separator. In certain embodiments, a layer of positive temperature coefficient material may be used. Illustrations

[0050] Illustration 1. A battery comprising a cathode comprised of a disordered rocksalt, anode, separator and localized high concentration electrolyte (LHCE) comprised of a solvating solvent, a diluent solvent, a lithium salt and a halogenated phosphorous additive in an additive amount of 0.02% to 5% by weight of the electrolyte.

[0051] Illustration 2. The battery of illustration 1, wherein the additive amount is 0.2% to 2%.

[0052] Illustration 3. The battery of either illustration 1 or 2, wherein the halogenated phosphorous additive has a molecular weight of at most 1000 g / mol. 144879-2997-1135, v. 4Atty. Doc. No. WCAT-198-A-WO

[0053] Illustration 4. The battery of any one of illustrations 1 to 3, wherein the halogenated phosphorous additive is comprised of one or more of a halogenated phosphate, halogenated phosphite and a halogenated phosphonate.

[0054] Illustration 5. The battery of either illustration 1 or 2, wherein the halogenated phosphorous additive is comprised of one or more of: O R' R" ,independently a halogen or substituted hydrocarbyl group having 1 to 12 carbons so long R, R’ and R” is substituted with at least one halogen if none of them is the halogen and R is bonded to the P with a C or halogen. Illustration 6. The battery of illustration 4, wherein the hydrocarbyl group is an unsubstituted or a substituted hydrocarbyl group having from 1 to 20 heteroatoms.

[0055] Illustration 7. The battery of either illustration 4 or 5, wherein at least one of R, R’ and R” is different.

[0056] Illustration 8. The battery of illustration 6, wherein each R, R’ and R” is the hydrocarbyl group and the hydrocarbyl group has 1 to 6 carbons.

[0057] Illustration 9. The battery of illustration 8, wherein R, R’ and R” are the same. 154879-2997-1135, v. 4Atty. Doc. No. WCAT-198-A-WO

[0058] Illustration 10. The battery of illustration 8, wherein at least one of R, R’ and R” is different.

[0059] Illustration 11. The battery of any one of illustration 5 to 10, wherein R is the substituted hydrocarbyl group having a halogen.

[0060] Illustration 12. The battery of illustration 11, wherein the substituted hydrocarbyl group is aliphatic.

[0061] Illustration 13. The battery of illustration 11, wherein the substituted hydrocarbyl group is branched or linear.

[0062] Illustration 14. The battery of any one of illustrations 5 to 13, wherein at least one of the hydrocarbyl groups is substituted with oxygen.

[0063] Illustration 15. The battery of illustration 14, wherein the oxygen is double bonded to a carbon.

[0064] Illustration 16. The battery of either illustration 14 or 15, wherein hydrocarbyl group substituted with oxygen has one or more of an ester, carbonate, ketone and aldehyde.

[0065] Illustration 17. The battery of any one of illustration 5 to 16, wherein the halogenated phosphorous additive has from 1 to 20 halogens.

[0066] Illustration 18. The battery of illustration 16 wherein the halogenated phosphorous additive has from 1 to 12 halogens.

[0067] Illustration 19. The battery of illustration 1, wherein the halogenated phosphorous additive is comprised of one or more of the following: tris(2,2,2-trifluoroethyl) phosphate; bis(2,2,2-trifluoroethyl) methylphosphonate; diethyl (difluoromethyl)phosphonate; triethyl 2- fluoro-2-phosphonoacetate; tris(1,1,1,3,3,3-hexafluoro-2-propyl) phosphite, Tris(2,2,3,3- tetrafluoropropyl)phosphate, Tris(1,1,1,3,3,3-hexafluoro-2-propyl) Phosphate, Bis(2,2,2- trifluoroethyl)(methoxycarbonylmethyl) phosphonate, Ethyl 2-(bis(2,2,2- trifluoroethoxy)phosphoryl)acetate, 2-(2,2,2-Trifluoroethoxy)-1,3,2-dioxaphospholane 2-Oxide, Lithium difluorobis(oxalato)phosphate, and tris(2,2,2-trifluoroethyl) phosphite.

[0068] Illustration 20. The battery of any one of the preceding illustrations, wherein the LHCE is comprised of a lithium bis(fluorosulfonyl)imide (LiFSI), dimethyl carbonate (DMC), 1,1,2,2-tetrafluoroethyl 2,2,3,3-tetrafluoropropyl ether (TTE) combination; LiFSI, DMC, 1,2- (1,1,2,2-Tetrafluoroethoxy)ethane (TFEE) combination; LiFSI, DMC, 1H,1H,5H- octafluoropentyl 1,1,2,2,-tetrafluoroethyl ether (OFPTFEE) combination; LiFSI, DMC, 1,3- 164879-2997-1135, v. 4Atty. Doc. No. WCAT-198-A-WO (1,1,2,2-Tetrafluoroethoxy)propane (TFEP) combination; LiFSI, DMC, 1H,1H,2’H,3H- decafluoro dipropyl ether (DFDPE) combination; LiFSI, ethyl methyl carbonate (EMC), TTE combination; LiFSI, EMC, TFEE combination; LiFSI, EMC, OFPTFEE combination; LiFSI, EMC, TFEP combination; LiFSI, EMC, DFDPE combination.

[0069] Illustration 21. The battery of any one of the preceding illustrations, wherein the disordered rocksalt is comprised of a DR having a formula: LixM’yMzO2-(a+b)FaZbwhere 1.0<x<1.75; 0≤y<0.55; 0.1<z<1; 0≤(a+b)<0.7; (b≥0) M’ is one or more of Ti, Ta, Zr, W, Nb, or Mo; M is one or more of Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Al, Zr, Y, Mo, Ru, Rh, Sn, Bi and Sb; Z is one or more of P, N and S. Examples

[0070] The following examples are intended to be illustrative and do not unduly limit the scope of the disclosure.

[0071] Battery cells are made with the same materials other than different electrolytes including different halogenated phosphorous and unhalogenated phosphorous additives. Battery cells are formed in a high purity argon filled glove box (M-Braun, O2 and humidity content < 0.1 ppm).

[0072] The disordered rocksalts are synthesized using Mn2O3, Li2CO3, Nb2O5, TiO2, and LiF precursors in amounts targeted to realize a disordered rock salt represented by Li1.31Mn0.4Nb0.1Ti0.19O1.77-xF0.23Axwhere x is zero in the same manner as paragraph 62 in WO2023 / 235473 except that the DR / carbon precursor ratio is 96:4 (powder to carbon weight ratio) as the active cathode material mixture and the drying was performed using a lab scale spray dryer (e.g., Buchi B-290 model).

[0073] In the case of the cathode, DR cathode active material was mixed with polyvinylidene fluoride (PVDF), carbon nanotube, and liquid 1-methyl-2-pyrolidinone (NMP) to form a slurry. The resulting slurry was deposited on an aluminum current collector and dried to form a composite cathode film. In the case of the anode, graphite anode active material was mixed with styrene- butadiene rubber (SBR) binder, carboxymethyl cellulose (CMC), and deionized water to form a slurry. The resulting slurry was deposited on a copper current collector and dried to form a 174879-2997-1135, v. 4Atty. Doc. No. WCAT-198-A-WO composite anode film. Each battery cell included composite cathode film, a polypropylene separator, electrolyte, and composite anode film.

[0074] A localized high salt concentration electrolyte is prepared by molar ratio. For example, the electrolyte referred to as “control” is prepared by mixing lithium bis(fluorosulfonyl)imide (LiFSI), dimethylcarbonate (DMC), and 1,1,2,2-tetrafluoroethyl 2,2,3,3-tetrafluoropropyl ether (TTE) in a 1 / 1.6 / 2 molar ratio, which unless otherwise stated is the electrolyte that is used in the Examples (with an additive comprised of a halogenated phosphorous additive) and Comparative Example (Control without a halogenated phosphorous additive or with phosphorous additive lacking halogenation “phosphorous additive”). The halogenated phosphorous additive and phosphorous additive is added by weight of the electrolyte (e.g., 0.5%, 1%, and 2%). The amount of electrolyte used is a lean amount to accentuate the effect of the additive on the performance of the battery. A lean electrolyte amount is an amount of electrolyte that is about 20% greater than the amount of open porosity in the cathode and anode (noting there is no open porosity in the Examples battery cells). The amount of electrolyte in the battery may be any useful such as from lean to 20X or 10X the volume of open porosity in the cathode and anode of the battery. It is noted that each set of batteries tested and shown each Table are self-consistent with the making of the control and are not comparable with the other set of batteries (i.e., control may vary due to differing lots or amounts particularly used for each set of batteries made).

[0075] The battery cell was then sealed followed by a first formation cycle that is 24 hours OCV (open circuit voltage) hold, followed by a 0.05C CC (constant current) charge to 4.45 V with a CV (constant voltage) hold until the charge current is smaller than 0.02C, and then a 0.05C CC discharge to 2.0 V. The second formation cycle is started with a 0.1C CC charge to 4.45 V with a CV hold until the charge current is smaller than 0.05C, and then a 0.1C CC discharge to 2.0 V. Cells were then cycled between 4.45 V and 2.0 V with 0.33C CC charge and 0.33C CC discharge cycling rate. (1C = 1.8 mA / cm2). All cycling was performed at 30oC.

[0076] Table 1 and Figure 1 show the cycling results of batteries made with a halogenated phosphorous additive (Example 1), phosphorous additive (Comparative Example 1) and without a phosphorous additive (control, which is also a comparative example). The halogenated phosphorous additive of Example 1 has the same structure as the phosphorous additive of Comparative Example 1 lacking halogenation. The cycling performance substantially improves when using the halogenated phosphorous additive of Example 1 compared to the control and 184879-2997-1135, v. 4Atty. Doc. No. WCAT-198-A-WO Comparative Example 1 batteries. Example 1 shows that halogenated phosphate additives significantly improve the cycle life of batteries having a cathode comprised of DR when used with an LHCE compared to batteries employing no phosphorous additive or phosphate additives without halogenation. 194879-2997-1135, v. 4Atty. Doc. No. WCAT-198-A-WO

[0077] Table 1 Example Cycle5 Electrolyte Formulation Cycle Life Capacitg , p p g ted phosphorous additives that are phosphonates on the cycling behavior of batteries having cathodes comprised of DR with varying levels of halogenation and chemical structure of the hydrocarbyl groups of the halogenated phosphorous additives. From Table 2 and Figure 2, the improvement of the cycling behavior may not be solely dependent of the level of halogenation but the structure of the halogenation. That is, hydrocarbyl groups bonded to the P directly through a carbon may desirably be comprised of oxygen such as in a carbonyl, ester, carbonate or aldehyde group, whereas halogenated alkyls directly bonded to the P may be less desirous (see Examples 2 -4). In contrast, it may be more desirous to have halogenated hydrocarbyl groups bonded through an oxygen to the P as shown in Example 2. 204879-2997-1135, v. 4Atty. Doc. No. WCAT-198-A-WO

[0079] Table 2 Cycle 5 Cycle Example Electrolyte Formulation Capacity 0 1a e an gure s ow e e ec o posporous a ves an aogenated phosphorous additives that are phosphites on the cycling behavior of batteries having cathodes comprised of DR with varying levels of halogenation From Table 3 and Figure 3, the improvement of the cycling of the halogenated phosphorous additive is substantial from the control. The degree of halogenation of the halogenated phosphorous additive may desirably be at least 1 to less than 10 as shown by Examples 1, 2, 5 and 6.

[0081] Table 3 Example Cycle5 Cycle Electrolyte Formulation 4 2 4a e an gure s ow e e ec o e concenra on o e aogenated phosphorous additives that are phosphates on the cycling behavior of batteries having cathodes comprised of DR. It is apparent that for this particular embodiment the improvement is most pronounced at lower concentrations such as demonstrated at 0.2% and 0.5% by weight additions of the halogenated phosphate additive of Examples 7 and 8. 214879-2997-1135, v.4Atty. Doc. No. WCAT-198-A-WO

[0083] Table 4 Example Cycle5 Electrolyte Formulation Cycle Life Capacity 2224879-2997-1135, v. 4

Claims

Atty. Doc. No. WCAT-198-A-WO CLAIMS CLAIMS What is claimed is:

1. A battery comprising a cathode comprised of a disordered rocksalt, anode, separator and localized high concentration electrolyte (LHCE) comprised of a solvating solvent, a diluent solvent, a lithium salt and a halogenated phosphorous additive in an additive amount of 0.02% to 5% by weight of the LHCE.

2. The battery of claim 1, wherein the additive amount is 0.2% to 2%.

3. The battery of claim 1, wherein the halogenated phosphorous additive has a molecular weight of at most 1000 g / mol.

4. The battery of claim 1, wherein the halogenated phosphorous additive is comprised of one or more of a halogenated phosphate, halogenated phosphite and a halogenated phosphonate.

5. The battery of claim 1, wherein the halogenated phosphorous additive is comprised of one or more of: O R' R" , , and4879-2997-1135, v. 4Atty. Doc. No. WCAT-198-A-WO where R, R’ and R” are each independently a halogen or a hydrocarbyl group having 1 to 12 carbons so long R, R’ and R” is substituted with at least one halogen if none of them is the halogen and R is bonded to the P with a C or halogen.

6. The battery of claim 5, wherein the hydrocarbyl group is an unsubstituted or a substituted hydrocarbyl group having from 1 to 20 heteroatoms.

7. The battery of claim 5, wherein at least one of R, R’ and R” is different.

8. The battery of claim 6, wherein each R, R’ and R” is the hydrocarbyl group and the hydrocarbyl group has 1 to 6 carbons.

9. The battery of claim 8, wherein R, R’ and R” are the same.

10. The battery of claim 8, wherein each of R, R’ and R” is different.

11. The battery of claim 6 wherein R is the substituted hydrocarbyl group having a halogen.

12. The battery of claim 11, wherein the substituted hydrocarbyl group is aliphatic.

13. The battery of claim 11, wherein the substituted hydrocarbyl group is branched or linear.

14. The battery of any one of claims 5 to 13, wherein at least one hydrocarbyl group is substituted with oxygen.

15. The battery of claim 14, wherein the oxygen is double bonded to a carbon.

16. The battery of claim 15, wherein hydrocarbyl group substituted with oxygen has one or more of an ester, carbonate, ketone and aldehyde.

17. The battery of claim 5, wherein the halogenated phosphorous additive has from 1 to 20 halogens.

18. The battery of claim 16 wherein the halogenated phosphorous additive has from 1 to 12 halogens.

19. The battery of claim 1, wherein the halogenated phosphorous additive is comprised of one or more of: tris(2,2,2-trifluoroethyl) phosphate; bis(2,2,2-trifluoroethyl) methylphosphonate; diethyl (difluoromethyl)phosphonate; triethyl 2-fluoro-2-phosphonoacetate; tris(1,1,1,3,3,3-hexafluoro-2-propyl) phosphite, Tris(2,2,3,3-tetrafluoropropyl)phosphate, Tris(1,1,1,3,3,3-hexafluoro-2-propyl) Phosphate, Bis(2,2,2-trifluoroethyl)(methoxycarbonylmethyl) phosphonate, Ethyl 2-(bis(2,2,2- trifluoroethoxy)phosphoryl)acetate, 2-(2,2,2-Trifluoroethoxy)-1,3,2-dioxaphospholane 2-Oxide, Lithium difluorobis(oxalato)phosphate, and tris(2,2,2-trifluoroethyl) phosphite..

20. The battery of claim 1, wherein the LHCE is comprised of a lithium bis(fluorosulfonyl)imide (LiFSI), dimethyl carbonate (DMC), 1,1,2,2-tetrafluoroethyl 2,2,3,3- 244879-2997-1135, v. 4Atty. Doc. No. WCAT-198-A-WO tetrafluoropropyl ether (TTE) combination; LiFSI, DMC, 1,2-(1,1,2,2-Tetrafluoroethoxy)ethane (TFEE) combination; LiFSI, DMC, 1H,1H,5H-octafluoropentyl 1,1,2,2,-tetrafluoroethyl ether (OFPTFEE) combination; LiFSI, DMC, 1,3-(1,1,2,2-Tetrafluoroethoxy)propane (TFEP) combination; LiFSI, DMC, 1H,1H,2’H,3H-decafluoro dipropyl ether (DFDPE) combination; LiFSI, ethyl methyl carbonate (EMC), TTE combination; LiFSI, EMC, TFEE combination; LiFSI, EMC, OFPTFEE combination; LiFSI, EMC, TFEP combination; LiFSI, EMC, DFDPE combination.

21. The battery of claim 1, wherein the disordered rocksalt is comprised of a DR having a formula: LixM’yMzO2-(a+b)FaZbwhere 1.0<x<1.75; 0≤y<0.55; 0.1<z<1; 0≤(a+b)<0.7; (b≥0) M’ is one or more of Ti, Ta, Zr, W, Nb, or Mo; M is one or more of Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Al, Zr, Y, Mo, Ru, Rh, Sn, Bi and Sb; Z is one or more of P, N and S. 254879-2997-1135, v. 4

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