FIELD OF THE INVENTION

The invention relates to organic electrolyte solvents, organic electrolytic solutions

utilizing the organic electrolyte solvents, and batteries utilizing the electrolytic solutions.

BACKGROUND OF THE INVENTION

It is generally known in the art to utilize various organic solvents as electrolytes for chargeable lithium type batteries. Various electrolytes include materials such as carbonates and cyclic esters as well as ethers. However, these conventional organic solvents are prone to decomposition during the cycling of a charge and discharge of a battery. Additionally, conventional organic solvent type electrolytes are prone to failure at

« high operating voltages such as greater than 4.0 volts. Such electrolytes may also be prone to thermal failure at elevated temperatures. Failures may result in reduced cycle life and decreased safety of batteries using such electrolytes. There is therefore a need in the art for an improved electrolytic solution that is stable at high voltages and at elevated temperatures/ There is also a need in the art for an improved electrolytic solution that improves the cycle life and safety of a battery incorporating the electrolytic solution.

SUMMARY OF THE INVENTION

In one aspect there is disclosed an organic electrolyte solvent that includes a

compound of the formula: R]-SO ₂ -NR ₂ -ORs wherein R ₁ is selected from alkanes, alkenes, alkynes, aryls and their substituted derivatives and perfluorinated analogues; R ₂ is selected from alkanes, alkenes, alkynes, aryls and their substituted derivatives; R ₃ is selected from alkanes, alkenes, alkynes, aryls and their substituted derivatives wherein the electrolyte solvent is stable at voltages of greater than 4.0 volts.

In one aspect there is disclosed an organic electrolyte solvent that includes a compound of the formula: R[O-SO ₂ -NR ₂ -OR ₃ wherein Ri is selected from alkanes, alkenes, alkynes, aryls and their substituted derivatives and perfluorinated analogues; R ₂ is selected from alkanes, alkenes, alkynes, aryls and their substituted derivatives; R ₃ is selected from alkanes, alkenes, alkynes, aryls and their substituted derivatives wherein the electrolyte solvent is stable at voltages of greater than 4.0 volts.

In another aspect there is disclosed an organic electrolytic solution that includes an organic electrolyte solvent that includes a compound of the formula: RrSO ₂ -NR ₂ -OR ₃ wherein Rj is selected from alkanes, alkenes, alkynes, aryls and their substituted derivatives and perfluorinated analogues; R ₂ is selected from alkanes, alkenes, alkynes, aryls and their substituted derivatives; R ₃ is selected from alkanes, alkenes, alkynes, aryls and their substituted derivatives wherein the electrolytic solution is stable at voltages of greater than 4.0 volts.

In another aspect there is disclosed an organic electrolytic solution that includes an organic electrolyte solvent that includes a compound of the formula: R]O-SO ₂ -NR ₂ -OR ₃ wherein R| is selected from alkanes, alkenes, alkynes, aryls and their substituted derivatives and perfluorinated analogues; R ₂ is selected from alkanes, alkenes, alkynes, aryls and their substituted derivatives; R ₃ is selected from alkanes, alkenes, alkynes, aryls and their substituted derivatives wherein the electrolytic solution is stable at voltages of greater than 4.0 volts.

In a further aspect there is disclosed a battery that includes a cathode, anode and electrolytic solution that includes an organic electrolyte solvent including a compound of the formula: Ri-SO ₂ -NRi-OR ₃ wherein Ri is selected from alkanes, alkenes, alkynes, aryls and their substituted derivatives and perfluorinated analogues; R ₂ is selected from alkanes, alkenes, alkynes, aryls and tlieir substituted derivatives; R ₃ is selected from alkanes, alkenes, alkynes, aryls and their substituted derivatives wherein the electrolytic solution is stable at voltages of greater than 4.0 volts. In a further aspect there is disclosed a battery that includes a cathode, anode and electrolytic solution that includes an organic electrolyte solvent including a compound of the formula: RiO-SO ₂ -NR ₂ -OR ₃ wherein Ri is selected from alkanes, alkenes, alkynes, aryls and their substituted derivatives and perfluorinated analogues; R ₂ is selected from alkanes, alkenes, alkynes, aryls and their substituted derivatives; R ₃ is selected from alkanes, alkenes, alkynes, aryls and their substituted derivatives wherein the electrolytic solution is stable at voltages of greater tli an 4.0 volts.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

In one aspect there is disclosed an organic electrolyte solvent that includes a compound of the formula: R ₁ -SO ₂ -NR ₂ -OR ₃ or : RiO-SO ₂ -NR ₂ -OR ₃ wherein Ri is selected from alkanes, alkenes, alkynes, aryls and their substituted derivatives and perfluorinated analogues; R ₂ is selected from alkanes, alkenes, alkynes, aryls and their substituted derivatives; R ₃ is selected from alkanes, alkenes, alkynes, aryls and tlieir substituted derivatives. The organic electrolyte solvent remains stable at voltages of greater than 4.0 volts. In another aspect, Rj ₃ R ₂ and R ₃ may be selected from linear alkyl, branched alky I ₃ partially fluorinated alkyl and fully fJuorinated alkyi groups having from 1 to 5 carbons. In a preferred aspect, R ₂ and R ₃ may include a methyl moiety.

In another aspect, there is disclosed an organic electrolytic solution that includes the organic electrolyte solvent that includes a compound of the formula: Ri-SO ₂ -NR ₂ -OR ₃ or: RiO-SO ₂ -NR ₂ -OR ₃ wherein Ri is selected from alkanes, alkenes, alkynes, aryls and their substituted derivatives and perfluorinated analogues; R ₂ is selected from alkanes, alkenes, alkynes, aryls and their substituted derivatives; R ₃ is selected from alkanes, alkenes, alkynes. aryls and their substituted derivatives. Additionally, an electrolyte salt may be dissolved in the organic electrolyte wherein the electrolytic solution remains stable at voltages of greater than 4.0 volts. The perfluorinated analogues may be synthesized by electrochemical fluorination (ECF) or direct fluorination of a desired substrate.

^" Various electrolyte salts may include lithium salts that are generally used in the field. In one aspect, lithium salts may be selected from the group consisting of: LiPFg, LiAsF ₆ , LiSbF ₆₃ LiBF ₄ , LiClO ₄ , LiCF ₃ SO ₃ , Li(CF ₃ SO ₂ ) ₂ N, Li(C ₂ F ₅ SO ₂ ) ₂ N, LiC ₄ F ₉ SO ₃ , Li(CF ₃ SO ₂ )^C, LiBPIi ₄ , LiBOB, and Li(CF ₃ SO ₂ )(CF ₃ CO)N and combinations thereof. The organic electrolyte solution may include the electrolyte salts in a concentration of from 0.5 molar to 3 molar.

The organic electrolyte solution may also include electrolyte additives selected from solid electrolyte interface (SEI) forming additives, cathode protecting agents, salt stabilizers, overcharge protecting additives, lithium depositing additives, salvation enhancers, as well as corrosion inhibitors and wetting agents.

In one aspect, the SEI forming additives may be utilized to improve the formation of an SEI layer on the surface of an anode of a battery, as will be discussed in more detail below. Ln one aspect, the SEl forming additives may be selected from the group consisting of: vinyl ene carbonate, vinyl ethylene carbonate, ethylene carbonate, ally] ethyl carbonate, vinyl acetate, divinyl adipate, acrylic acid nitrile, 2-vinyl pyridine, maleic anhydride, maleimides, methyl cinnamate, phosphonate, vinyl-containing silane-based compounds, furan derivatives that contain two double bonds in each molecule, sulfur-based compounds, including SO ₂ , polysulfide, cyclic alkyl sulfites, aryl sulfites, nitrates, nitrites, haiogenated ethylene carbonate, haiogenated lactone, methyl chloroformate, carboxyl phenol, aromatic esters, anhydrides, succinimide, iV-benzyloxy carbonyloxy succinimide, aromatic isocyanates, B ₂ O ₃ , organic borates, boroxine compounds, lithium salt-based boron compounds, halogenated organic compounds, polydimethylsiloxane, siianes, tris(pentafluorophenyl) borane, and alkali metal salts. The cathode protecting agents may also be included in the organic electrolyte solution. The cathode protecting agents may be selected from the group consisting of: amine-based organic bases such as butylamine, carbodiimide based compounds such as N, N- dicyclohexylcarbodiimide, N, JV-diethylamino uϊmethylsilane.

Various salt stabilizers may be utilized in the organic electrolyte solution and may be selected from the group consisting of: LiF, Lewis bases including tris(2 ₃ 2,2-trifluoroethyl) phosphate, amide-based compounds including l-methyl-2-pyrro]idinone, fluorinated carbamate and hexamethyl-phosphoramide.

Additionally, overcharge protecting additives may be included in the organic electrolyte solution. Ln one aspect, the overcharge protecting additives may be selected from the group consisting of: metallocenes, tetracyanoethylene, tetramethylphenylenediamine, dihydrophenazine derivatives bearing either 2-hydroxypropyl or ethyl substituents on both N atoms, substituted aromatic or heterocyclic compounds and their alkali metal salts, anisole- family compounds, 2,5-ditertbutyI-l ,4-dimethoxybenzene, monomethoxy benzene class compounds, hexaethyl benzene, bipyridyl or biphenyl carbonates, difluoroanisoles, S- or N-containing heterocyclic aromatic compounds such as thianthrene and 2,7-diacetyl thianthrene, phenothiazinebased compounds, lithium fluorododecaborates, xylene, cyclohexylbenzene, biphenyl, 2,2-diphenylpropane, phenyl-/e/7-butyl carbonate, phenyl-R- phenyl compounds, 3-thiopheneacetonitrile, heterocyclic compounds including furan, thiophene, and JV-methylpyrrole, 3,4-ethylenedioxythiophene, and LiBOB. Various lithium depositing additives may also be included in the organic electrolyte solution. The lithium depositing additives may be selected from the group consisting of: SO ₂ compounds, polysulfide, water, 2-methyltetrahydrofuran, 2-methylthiophene, nitromethane, tetraallcylammonium chlorides with a long alkyl chain, cetyltrimethylammonium chlorides, lithium and tetraethyl ammonium salts of perfluorooctanesulfonate, perfluoropolyethers, nitrile sucrose, nitrile cellulose, AlI ₃ , SnI, HF, and fJuoro ethylene carbonate.

Salvation enhancers may also be included in the organic electrolyte solution. Various salvation enhancers include borates, boranes and borole compounds.

In addition, corrosion inhibitors and wetting agents may also be included in the organic electrolyte solution. Various corrosion inhibitors and wetting agents may include agents selected from the group consisting of: LiBOB, LiODFB ₅ ionic and non-ionic surfactants, cyclohexane, trialkyl phosphate, linear esters with high molecular weight including methyl decanoate and dodecyl acetate, tertiary carboxylic acids, and P ₂ O ₅ .

Additionally, other solvents may be included in the organic electrolyte solution. The additional solvents may include organic carbonates, ionic liquids, silanes and sulfones.

In another aspect, a lithium battery mat includes the organic electrolytic solution is described. Generally, the battery may include a positive and negative electrode as well as a separator material and the organic electrolytic solution. Various types of batteries including lithium batteries such as lithium secondary batteries, lithium ion batteries and lithium ion polymer batteries as well as lithium primary batteries may utilize the organic electrolytic solution.

In one aspect, the cathode may include an active material for which absorption and release of various cations of the lithium salts can take place. In one aspect, the active material may include the cations. For example, in a battery that is charged and discharged through the migration of lithium ions such as a lithium ion secondary battery, various lithium composite oxides containing lithium and a transition metal may be utilized. Various examples include composite oxides with the general formula LiMO ₂ where M can be any metallic elements or combination of metallic elements such as cobalt, aluminum, chromium, manganese, nickel, iron, vanadium, magnesium, titanium, zirconium, niobium, molybdenum, copper, zinc, indium, strontium, lanthanum, and cesium. Additionally, the active material can be made of a material with the chemical formula LiMn ₂ O ₄ or a material with the general formula LiMPO ₄ where M can be any metallic element or combination of elements such as cobalt, aluminum, chromium, manganese, nickel, iron, vanadium, magnesium, titanium, zirconium, niobium, molybdenum, copper, zinc, indium, strontium, lanthanum, and cesium The positive electrode of the battery disclosed may include any of the active materials that may be held on an electrically conductive member that includes metal or another conductive element. Various conductive members including rod-shaped, plate or foil bodies as well as mesh or other type structures. In addition to the active material and electron conducting material various other materials such as binders may also be included. Various binders including polyvinylidene fluoride, polyvinyl diamine fluoride, polytetrafiuoroethylene, polyvinyl diamine fluoride, hexafluoropropylene copolymers, styrene butadiene rubber and various other materials may be utilized.

The negative electrode or anode may also include an active material for which absorption and release of the cation described above can take place. Various negative electrode active materials may include a carbon material having an amorphous structure and/or graphite structure. For example, various kinds of active materials commonly utilized in lithium batteries may include natural graphite, mezocarbon microbeads, highly ordered pyrolytic graphite, hard carbon and soft carbon, as well as additional materials. Further, various other active materials that are able to maintain the electric potential of the negative electrode such as lithium titanate may also be utilized. Additionally, elements that can alloy with lithium such as tin, silicon, antimony, bismuth, silver, zinc, aluminum, lead, germanium, arsenic and composite materials containing said elements can be utilized as negative electrode active materials. As with the positive electrode, the negative electrode may include an active material that is held on an electrically conductive member that includes metal or the like. Various structures including plates, rods, foils and other type structures may be utilized. As with the previously described cathode, a binder material may be mixed with the active material as well as other additives such as plasticizers or other such additives to form the negative electrode of the battery.

The battery also includes the electrolytic solution as described above. The electrolytic solution may include an organic electrolyte solvent including a compound of the formula: Ri-SO ₂ -NR ₂ -OR ₃ or R]O-SO ₂ -NR ₂ -OR ₃ wherein R ₁ is selected from alkanes, alkenes, alkynes, aryls and their substituted derivatives and perfluorinated analogues: R ₂ is selected from alkanes, alkenes. alkynes, aryls and their substituted derivatives; R ₃ is selected from alkanes, alkenes, alkynes, aryls and their substituted derivatives, and an electrolyte salt dissolved in the organic electrolyte wherein the battery is stable at voltages of greater than 4.0 volts.

Examples Preparation of N-methosy-N-methyl-methanesulfonamide:

To a 3-neck 1.0-L round-bottomed flask (RBF) equipped with dry ice/liquid nitrogen bath, mechanical stirrer, dry nitrogen gas inlet, thermoprobe, addition funnel, and bubbler were charged with methanesulfonyl chloride (25 g, 0.218 M), N,O- dimethylhydroxylamine hydrochloride (22.35g 0.229 M) and anhydrous dichloromethane (200 mL). . The system was flushed with nitrogen and then cooled to O ⁰ C. While stirring at this temperature, anhydrous trimethylamine (3.00 equivalents) was added dropwise and the resulting reaction mixture was stirred and allowed to warm up to room temperature and stirred overnight. The reaction mixture was cooled to O ⁰ C and filtered to remove the solid (triethylamine hydrochloride) and the solvent was removed on a rotary evaporator. The reaction mixture may be purified though a short pad of celite and eluted with ether, with subsequent removal of the ether. The reaction product may be pulled under high vacuum overnight to yield a pure product.

Although preferred embodiments of the invention have been described using specific terms, devices, and methods, such description is for illustrative purposes only. The words used are words of description rather than of limitation. It is to be understood that changes and variations may be made by those of ordinary skill in the art without departing from the spirit or the scope of the present invention which is set forth in the following claims. In addition, it should be understood that aspects of the various embodiments may be interchanged, both in whole, or in part. Therefore, the spirit and scope of the appended claims should not be limited to the description of the preferred versions contained therein.