[go: up one dir, main page]

WO2012174704A1 - Solutions électrolytiques pour batterie contenant des composés de phosphites aromatiques - Google Patents

Solutions électrolytiques pour batterie contenant des composés de phosphites aromatiques Download PDF

Info

Publication number
WO2012174704A1
WO2012174704A1 PCT/CN2011/075941 CN2011075941W WO2012174704A1 WO 2012174704 A1 WO2012174704 A1 WO 2012174704A1 CN 2011075941 W CN2011075941 W CN 2011075941W WO 2012174704 A1 WO2012174704 A1 WO 2012174704A1
Authority
WO
WIPO (PCT)
Prior art keywords
electrolyte solution
battery
battery electrolyte
lithium
alkyl
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Ceased
Application number
PCT/CN2011/075941
Other languages
English (en)
Inventor
Qian Huang
Juntao Xia
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Dow Global Technologies LLC
Original Assignee
Dow Global Technologies LLC
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Dow Global Technologies LLC filed Critical Dow Global Technologies LLC
Priority to PCT/CN2011/075941 priority Critical patent/WO2012174704A1/fr
Publication of WO2012174704A1 publication Critical patent/WO2012174704A1/fr
Anticipated expiration legal-status Critical
Ceased legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/05—Accumulators with non-aqueous electrolyte
    • H01M10/052—Li-accumulators
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/05—Accumulators with non-aqueous electrolyte
    • H01M10/056—Accumulators with non-aqueous electrolyte characterised by the materials used as electrolytes, e.g. mixed inorganic/organic electrolytes
    • H01M10/0564—Accumulators with non-aqueous electrolyte characterised by the materials used as electrolytes, e.g. mixed inorganic/organic electrolytes the electrolyte being constituted of organic materials only
    • H01M10/0566—Liquid materials
    • H01M10/0567—Liquid materials characterised by the additives
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/05—Accumulators with non-aqueous electrolyte
    • H01M10/052—Li-accumulators
    • H01M10/0525—Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/05—Accumulators with non-aqueous electrolyte
    • H01M10/056—Accumulators with non-aqueous electrolyte characterised by the materials used as electrolytes, e.g. mixed inorganic/organic electrolytes
    • H01M10/0564—Accumulators with non-aqueous electrolyte characterised by the materials used as electrolytes, e.g. mixed inorganic/organic electrolytes the electrolyte being constituted of organic materials only
    • H01M10/0565—Polymeric materials, e.g. gel-type or solid-type
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M2300/00—Electrolytes
    • H01M2300/0017—Non-aqueous electrolytes
    • H01M2300/0025—Organic electrolyte
    • H01M2300/0028—Organic electrolyte characterised by the solvent
    • H01M2300/0037—Mixture of solvents
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M2300/00—Electrolytes
    • H01M2300/0017—Non-aqueous electrolytes
    • H01M2300/0025—Organic electrolyte
    • H01M2300/0028—Organic electrolyte characterised by the solvent
    • H01M2300/0037—Mixture of solvents
    • H01M2300/004—Three solvents
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
    • Y02E60/10—Energy storage using batteries

Definitions

  • the present invention relates to nonaqueous electrolyte solutions that contain an aromatic phosphite compound.
  • Lithium batteries are widely used as primary and secondary batteries for vehicles and many types of electronic equipment. These batteries tend to have high energy and power densities and for that reason are favored in many applications.
  • the electrolyte solution in a lithium battery is by necessity a nonaqueous type.
  • the nonaqueous electrolyte solution is generally a high dielectric content solution of a lithium salt in an organic solvent or a mixture of organic solvents.
  • Various linear and cyclic carbonates are commonly used, but certain esters, alkyl ethers, nitriles, sulfones, sulfolanes, sultones and siloxanes may also serve as the solvent. In many cases, the solvent may contain two or more of these materials.
  • Polymer gel electrolyte solutions are also known.
  • Phosphite compounds also have been evaluated. These phosphite compounds include, for example, trimethyl phosphite (see, e.g., Yao et al., "Comparative Study of trimethylphosphite and trimethylphosphate as electrolyte additives in lithium ion batteries", J. Power Sources (2005), 144(1), 170- 175) and tris (2,2,2- trifluoroethyl)phosphite (see, e.g., Zhang et al., "Tris(2,2,2-trifluoroethyl)phosphite as a cosolvent for nonflammable electrolyte in Li-ion batteries", J. Power Sources 2003, 113(1) 166).
  • trimethyl phosphite see, e.g., Yao et al., "Comparative Study of trimethylphosphite and trimethylphosphate as electrolyte additives in lithium ion batteries", J. Power Sources (2005)
  • USP 6,939,647 describes other trialkyl phosphites as additives for lithium ion battery electrolyte solutions.
  • US Published Patent Application No. 2007/0048622 mentions a number of phosphite compounds as possible battery electrolyte additives, although it reports experimental data for only a specific dioxaphospholane (a cyclic phosphite).
  • This specific dioxaphospholane (4-methyl-2-(2,2,3,3- tetrafluoropropoxy)l,3,2-dioxaphospholane) has minimal effect on the flame resistance of the battery electrolyte solution, even when used in quantities as much as 30% of the electrolyte solution.
  • WO 2010/074838 describes battery electrolyte solutions that contain aromatic phosphate compounds having the structure
  • a 1 is a radical that contains one or more aromatic rings; each R is independently an alkylene diradical which may contain 1, 2 or 3 carbon atoms and which is bonded directly to a carbon atom of an aromatic ring of the A 1 group; each R 1 is independently hydrogen, halogen, OH, a hydrocarbyl group having up to 12 carbon atoms or an alkoxyl group having up to 12 carbon atoms; or two R 1 groups attached to the same phosphorus atom may together form a ring structure that includes the phosphorus atom; and x is an integer of at least 2.
  • This invention is in one aspect a battery electrolyte solution comprising at least one lithium salt and a nonaqueous solvent in which the lithium salt is soluble, wherein from 0.01 to 10% of the weight of the battery electrolyte solution is at least one tris(alkyl-substituted aryl) phosphite compound.
  • This invention is also an electrical battery comprising an anode, a cathode, a separator disposed between the anode and cathode, and a nonaqueous battery electrolyte solution in contact with the anode and cathode, wherein the battery electrolyte solution comprises at least one lithium salt, a nonaqueous solvent in which the lithium salt is soluble, and wherein from about 0.01 to 10% by weight of the weight of the battery electrolyte solution is at least one tris(alkyl-substituted aryl) phosphite compound.
  • the tris(alkyl-substituted aryl) phosphite compound provides good thermal stabilization to the battery electrolyte solution.
  • the battery electrolyte solution is resistant to thermal degradation, is less likely to engage in thermal runaway reactions and is resistant to combustion.
  • the tris(alkyl- substituted aryl) phosphite compounds have minimal adverse impact on the performance of the battery and in some cases has been seen to ac ially increase discharge capacity.
  • Figure 1 illustrates differential scanning calorimetry curves for one comparative battery electrolyte solution and three battery electrolyte solutions in accordance with the invention.
  • Figure 2 is a graph of 0.1C discharge curves for three anode half-cells in accordance with the invention and one comparative anode half-cell.
  • Figure 3 is a graph of discharge curves for three cathode half-cells in accordance with the invention and one comparative anode half-cell.
  • Figure 4 is a graph of discharge curves for three cathode half-cells in accordance with the invention and one comparative anode half-cell.
  • Figure 5 is a graph of 0.1C discharge cures for three batteries in accordance with the invention and one comparative battery.
  • Figure 6A is a differential scanning calorimetry (DSC) curve of a comparative battery electrolyte solution (Comparative Sample C).
  • Figure 6B is a DSC curve of a battery electrolyte solution of the invention (Example 7).
  • Figure 7A is a DSC curve of a fully charged MCMB electrode in a comparative battery electrolyte solution (Comparative Sample C).
  • Figure 7B is a DSC curve of a fully charged MCMB electrode in a battery electrolyte solution of the invention (Example 7).
  • the tris(alkyl-substituted aryl) phosphite compound can be represented by the structure
  • each Ar independently represents an aryl group
  • each R independently represents an alkyl group
  • each m is at least one.
  • the Ar groups each may be phenyl, naphthyl, or other fused ring struc ire.
  • the R groups each may be linear, branched and/or cyclic, and may contain further substituents such as halogen, aryl, and the like.
  • the R groups each preferably have up to 20 carbon atoms, more preferably up to 8 carbon atoms and still more preferably up to 4 carbons.
  • the R groups preferably are bonded to the respective Ar groups through tertiary carbon atoms.
  • Each R is most preferably t-butyl.
  • Each m is preferably from 1 to 4, more preferably from 1 to 2 and more preferably 2.
  • a preferred class of phosphite compounds, in which the Ar groups are phenyl, have the structure II, in which R and m are as defined before:
  • butylphenyl)phosphite which has the structure:
  • the tris(alkyl-substituted aryl) phosphite compound(s) may constitute from about 0.01 to as much as 10% of the total weight of the battery electrolyte solution.
  • a preferred upper amount is up to 5% of the total weight of the battery electrolyte solution, and a more preferred upper amount is up to 2% or, still more preferably, up to 1% of the total weight of the battery electrolyte solution.
  • a preferred lower amount is at least 0.1%, more preferably 0.25%, of the total electrolyte solution weight.
  • the other main components of the battery electrolyte solution are a lithium salt and a nonaqueous solvent for the lithium salt.
  • the lithium salt may be any that is suitable for battery use, including inorganic lithium salts such as LiAsFe, LiPFe, LiB(C204)2, L1BF4, L1BF2C2O4, LiC104, LiBrC and LiI04 and organic lithium salts such as LiB(C6H5)4, L1CH3SO3, Li (S02C2Fs)2 and LiCFsSOa.
  • LiPFe, LiClC-4, L1BF4, LiAsF 6 , L1CF3SO3 and LiN(S0 2 CF 3 )2 are preferred types, and LiPFe is an especially preferred lithium salt.
  • the lithium salt is suitably present in a concentration of at least 0.5 moles/liter of electrolyte solution, preferably at least 0.75 moles/liter, up to 3 moles/liter and more preferably up to 1.5 moles/liter.
  • the nonaqueous solvent may include, for example, one or more linear alkyl carbonates, cyclic carbonates, cyclic esters, linear esters, cyclic ethers, alkyl ethers, nitriles, sulfones, sulfolanes, siloxanes and sultones. Mixtures of any two or more of the foregoing types can be used. Cyclic esters, linear alkyl carbonates, and cyclic carbonates are preferred types of nonaqueous solvents.
  • Suitable linear alkyl carbonates include dimethyl carbonate, diethyl carbonate, methyl ethyl carbonate and the like.
  • Cyclic carbonates that are suitable include ethylene carbonate, propylene carbonate, butylene carbonate and the like.
  • Suitable cyclic esters include, for example, ⁇ -butyrolactone and ⁇ -valerolactone.
  • Cyclic ethers include tetrahydrofuran, 2-methyltetrahydrofuran, tetrahydropyran and the like.
  • Alkyl ethers include dimethoxyethane, diethoxyethane and the like.
  • Nitriles include mononitriles such as acetonitrile and propionitrile, dinitriles such as glutaronitrile, and their derivatives.
  • Sulfones include symmetric sulfones such as dimethyl sulfone, diethyl sulfone and the like, asymmetric sulfones such as ethyl methyl sulfone, propyl methyl sulfone and the like, and their derivatives.
  • Sulfolanes include tetramethylene sulfolane and the like.
  • Some preferred solvent mixtures include a cyclic carbonate/linear alkyl carbonate mixture at a volume ratio of from 15:85 to 40:60; a cyclic carbonate/cyclic ester mixture at a volume ratio of from 20:80 to 60:40: a cyclic carbonate/cyclic ester/linear alkyl carbonate mixture at volume ratios of 20-48:50-78:2-20; and a cyclic ester/linear alkyl carbonate mixture at a volume ratio of from 70:30 to 98:2.
  • Solvent mixtures of particular interest are mixtures of ethylene carbonate and propylene carbonate at a volume ratio of from 15:85 to 40:60; mixtures of ethylene carbonate and dimethyl carbonate or ethylene carbonate and diethyl carbonate at a volume ratio of from 15:85 to 40:60; mixtures of ethylene carbonate, diethyl carbonate and dimethyl carbonate at a volume ratio of from 20-60:2-78:2-78; mixtures of ethylene carbonate, propylene carbonate and dimethyl carbonate at a volume ratio of 20-48:50- 78:2-20, and mixtures of propylene carbonate and dimethyl carbonate at a volume ratio of from 15:85 to 40:60.
  • additives may be present in the battery electrolyte solution, in addition to the components already mentioned. These may include, for example, additives which promote the formation of a solid electrolyte interface at the surface of a graphite electrode; various cathode protection agents; lithium salt stabilizers; lithium deposition improving agents; ionic solvation enhancers; corrosion inhibitors; wetting agents; flame retardants; and viscosity reducing agents. Many additives of these types are described by Zhang in “A review on electrolyte additives for lithium-ion batteries", J. Power Sources 162 (2006) 1379-1394.
  • Agents which promote solid electrolyte interface (SEI) formation include various polymerizable ethylenically unsaturated compounds, various sulfur compounds, as well as other materials.
  • Suitable cathode protection agents include materials such as N,N- diethylaminotrimethylsilane and LiB(C204)2.
  • Lithium salt stabilizers include LiF, ti"is(2,2,2-trifluoroethyl)phosphite, l-methyl-2-pyrrolidinone, fluorinated carbamate and hexamethylphosphoramide.
  • lithium deposition improving agents include sulfur dioxide, polysulfides, carbon dioxide, surfactants such as tetraalkylammonium chlorides, lithium and tetraethylammonium salts of perfluorooctanesulfonate, various perfluoropolyethers and the like. Crown ethers can be suitable ionic solvation enhancers, as are various borate, boron and borole compounds.
  • LiB(C204)2 and L1F2C2O4 are examples of aluminum corrosion inhibitors. Cyclohexane, trialkyl phosphates and certain carboxylic acid esters are useful as wetting agents and viscosity reducers. Some materials, such as LiB(C204)2, may perform multiple functions in the electrolyte solution.
  • the various other additives may together constipate up to 20%, preferably up to
  • the battery electrolyte solution is conveniently prepared by dissolving or dispersing the lithium salt, the tris(alkyl-substituted aryl) phosphite and any other additives as may be used into the nonaqueous solvent.
  • the order of mixing is in general not critical.
  • the water content of the resulting battery electrolyte solution should be as low as possible. A water content of 50 ppm or less is desired and a more preferred water content is 30 ppm or less.
  • the various components can be individually dried before forming the electrolyte solution, and/or the formulated electrolyte sohition can be dried to remove residual water.
  • the drying method selected should not degrade or decompose the various components of the electrolyte solution, nor promote undesired reactions between them. Thermal methods can be used, as can drying agents such as molecular sieves.
  • a battery containing the battery electrolyte solution of the invention can be of any useful construction.
  • a typical battery construction includes an anode and cathode, with a separator and the electrolyte solution interposed between the anode and cathode so that ions can migrate through the electrolyte solution between the anode and the cathode.
  • the assembly is generally packaged into a case.
  • the shape of the battery is not limited.
  • the battery may be a cylindrical type containing spirally-wound sheet electrodes and separators.
  • the battery may be a cylindrical type having an inside-out structure that includes a combination of pellet electrodes and a separator.
  • the battery may be a plate type containing electrodes and a separator that have been superimposed.
  • Suitable anode materials include, for example, carbonaceous materials such as natural or artificial graphite, carbonized pitch, carbon fibers, graphitized mesophase microspheres, furnace black, acetylene black and various other graphitized materials.
  • the carbonaceous materials may be bound together using a binder such as a poly(vinylidene fluoride), polytetrafluoroethylene, a styrene-butadiene copolymer, an isoprene rubber, a polyvinyl acetate), a poly(ethyl methacrylate), polyethylene or nitrocellulose.
  • a binder such as a poly(vinylidene fluoride), polytetrafluoroethylene, a styrene-butadiene copolymer, an isoprene rubber, a polyvinyl acetate), a poly(ethyl methacrylate), polyethylene or nitrocellulose.
  • s utable anode materials include lithium metal, lithium alloys and other lithium compounds such as a lithium titanate anode.
  • Suitable cathode materials include inorganic compounds such as transition metal oxides, transition metal/lithium composite oxides, lithium/transition metal composite phosphates, transition metal sulfides, metal oxides, and transition metal silicates.
  • transition metal oxides include MnO, V2O5, V6O13 and T1O2.
  • Transition metal/lithium composite oxides include lithium/cobalt composite oxides whose basic composition is approximately LiCo02, lithium/nickel composite oxides whose basic composition is approximately LiNiC , lithium/manganese composite oxides whose basic composition is approximately LiMmC or LiMnC and lithium/nickel/manganese/cobalt oxide electrodes whose basic composition is LiNixMn y Co x 02 or Li(Li a NixMnyCox)02, where x, y, z and a are such as to provide an electrostatically neutral compound
  • part of the cobalt, nickel or manganese can be replaced with one or two metals such as Al, Ti, V, Cr, Fe, Co, Ni, Cu, Zn, Mg, Ga or Zr.
  • Lithium/transition metal composite phosphates include lithium iron phosphate, lithium manganese phosphate, lithium cobalt phosphate, lithium iron manganese phosphate and the like.
  • useful metal oxides include SnC>2 and S1O2.
  • useful metal silicates include lithium iron orthosilicate.
  • the electrodes are each generally in electrical contact with or formed onto a current collector.
  • a suitable current collector for the anode is made of a metal or metal alloy such as copper, a copper alloy, nickel, a nickel alloy, stainless steel and the like.
  • Suitable current collectors for the cathode include those made of aluminum, titanium, tantalum, alloys of two or more of these and the like.
  • the separator is interposed between the anode and cathode to prevent the anode and cathode from coming into contact with each other and short-circuiting.
  • the separator is conveniently constructed from a nonconductive material. It should not be reactive with or soluble in the electrolyte solution or any of the components of the electrolyte solution under operating conditions.
  • Polymeric separators are generally suitable. Examples of suitable polymers for forming the separator include polyethylene, polypropylene, polybutene-1, poly-3-methylpentene, ethylene-propylene copolymers, polytetrafluoroethylene, polystyrene, polymethylmethacrylate, polydimethylsiloxane, polyethersulfones and the like.
  • the separator is generally porous, being in the form of a porous sheet, nonwoven or woven fabric or the like.
  • the porosity of the separator is generally 20% or higher, up to as high as 90%. A preferred porosity is from 30 to 75%.
  • the pores are generally no larger than 0.5 microns, and are preferably up to 0.05 microns in their longest dimension.
  • the separator is typically at least one micron thick, and may be up to 50 microns thick. A preferred thickness is from 5 to 30 microns.
  • the battery is preferably a secondary (rechargeable) lithium battery.
  • the discharge reaction includes a dissolution or delithiation of lithium ions from the anode into the electrolyte solution and concurrent incorporation of lithium ions into the cathode.
  • the charging reaction conversely, includes an incorporation of lithium ions into the anode from the electrolyte solution.
  • lithium ions are reduced on the anode side, at the same time, lithmm ions in the cathode material dissolve into the electrolyte solution.
  • the presence of the tris(alkyl-substituted aryl) phosphite compound described herein improves battery safety and battery life by stabilizing the electrolyte sohation against thermal degradation and runaway reactions, and/or otherwise reducing the ability of the electrolyte solution to catch on fire.
  • Thermal degradation and runaway reactions can occur due to several circumstances, including (1) mechanical damage to the battery, which may cause short-circuiting within the battery structure; (2) thermal abuse of the battery, which is mainly due to storing and/or operating the battery under high temperature conditions; and (3) electrical conditions such as overcharging or the creation of electrical shorts.
  • Overcharge situations can cause lithium to form a dendritic structure.
  • the dendritic structure can extend through the electrolyte solution and through the separator between the cathode and the anode, causing a short circuit.
  • the short circuit can allow a very large current to flow through the electrolyte solution over a very short time period, releasing heat that can cause degradation of the electrolyte solution or even runaway reactions to occur.
  • the runaway reactions can even cause the electrolyte solution to catch fire in the absence of a flame retardant or thermal runaway inhibitor. Even if the electrolyte solution does not catch on fire, the heat released by the runaway reactions can severely shorten the battery life.
  • the tris(alkyl-substituted aryl) phosphite compound When present in small bi.it effective amounts, the tris(alkyl-substituted aryl) phosphite compound has little or no adverse affect on battery performance. Discharge capacities are often equal to or even exceed those of otherwise like batteries that lack the tris(alkyl-substituted aryl) phosphite. In addition, batteries in accordance with the invention have been seen to retain their discharge capacities better than when no tris(alkyl-substituted aryl) phosphite is present in the electrolyte solution.
  • Cycling stability can be evaluated by running the battery through a fixed number of char e/discharge cycles, at a given charge/discharge rate, and measuring the capacity of the battery at the start and at the end of the evaluation. Capacity tends to fall as the battery continues to be charged and discharged, when the battery electrolyte solution is a simple solution of lithium salt in a carbonate or mixed carbonate solvent. However, when the battery electrolyte solution contains a small amount of the tris(alkyl- substituted aryl) phosphite, this loss of discharge capacity upon cycling is often greatly
  • the battery of the invention can be used in industrial applications such as electric vehicles, hybrid electric vehicles, plug-in hybrid electric vehicles, aerospace, e- bikes, etc.
  • the battery of the invention is also useful for operating a large number of electrical and electronic devices, such as computers, cameras, video cameras, cell phones, PDAs, MP3 and other music players, televisions, toys, video game players, household appliances, power tools, medical devices such as pacemakers and defibrillators, among many others.
  • electrical and electronic devices such as computers, cameras, video cameras, cell phones, PDAs, MP3 and other music players, televisions, toys, video game players, household appliances, power tools, medical devices such as pacemakers and defibrillators, among many others.
  • Battery electrolyte solutions Four battery electrolyte solutions are prepared.
  • Each battery electrolyte solution is a 1M solution of LiPF6 in a 1:1:1 (WV/V) mixture of ethylene carbonate, diethyl carbonate and dimethyl carbonate.
  • Comparative Battery Electrolyte Solution A contains no other additives.
  • Battery Electrolyte Solutions 1-3 contain, respectively, 0.25, 0.5 and 1.0 weight percent of tris(2,4-di-tert-butylphenyl) phosphite.
  • Each of the battery electrolyte solutions exhibits two endothermic peaks that are indicative of thermal degradation.
  • the onset temperature for each of these peaks increases with the addition of tris(2,4-di-tert-butylphenyl)phosphite in amounts ranging from 0.25 to 1 weight percent.
  • the onset temperature for the first endothermic peak increases from about 37°C to about 51°C as the phosphite concentration is increased from zero to 1%; that for the higher endothermic peak increases from about 164°C to about 199°C.
  • the higher onset temperatures indicate greater thermal stability in the examples of the invention, compared with the control.
  • the higher temperature peaks become smaller as more of the phosphite compound is added into the electrolyte solution, indicating that less heat is generated dxiring the exothermic events.
  • Separate model CR 2025 coin cells with a Mesocarbon Microbead (MCMB) anode (85% mesocarbon microbeads, 10% conductive carbon and 5% polytetrafluoroethene) and a metallic lithium sheet cathode are prepared with each of Examples 1-3 and Comparative Sample B as the electrolyte solution.
  • the discharge capacity and coulomb efficiency of these cells is evaluated by galvanostatic cycling at a C/10 rate, using cutoff potentials of 0.01V vs. Li/Li+ for charge and 1.5 V vs. Li/Li+ for discharge.
  • the results of the discharge capacity testing are shown graphically in Figure 2.
  • the discharge capacity of the half-cell containing Comparative Battery Electrolyte Solution A is indicated by reference numeral A.
  • the discharge capacity for this cell peaks at about 285 mAh/g after about 5 charge/discharge cycles, and then gradually decays to below 260 mAh/g after 40 cycles.
  • Discharge capacities for the half-cells containing Battery Electrolyte Solutions 1, 2 and 3 are indicated by reference numerals 1-3, respectively.
  • the cells containing Solutions 1 and 2 are seen to have discharge capacities of about 300 mAh/g, and to retain these capacities over the entire test of 40 charge/discharge cycles.
  • the cell containing Battery Electrolyte Solution 3 (1% of the phosphite compound) has a peak discharge capacity of about 275 mAh/g, which is slightly lower than that of the cell containing Comparative Battery Electrolyte Solution A, but, unlike the control, this cell retains essentially its entire peak discharge capacity over the entire test of 40 charge/discharge cycles.
  • the coulomb efficiency of each of the cells is close to 100% over the entire test of
  • Each battery electrolyte solution is a 1M solution of LiPFe in a 1:1 (V V) mixture of ethylene carbonate and diethyl carbonate.
  • Comparative Battery Electrolyte Solution B contains no other additives.
  • Battery Electrolyte Sohitions 4-6 contain, respectively, 0.25, 0.5 and 1.0 weight percent of tris(2,4-di-tert-butylphenyl) phosphite.
  • Separate model CR 2025 coin cells with a Lio 5C0O2 cathode (ALE company) and a metallic lithium sheet anode are prepared with each of Battery Electrolyte Solutions 4-6 and Comparative Battery Electrolyte Solution B as the electrolyte solution.
  • the discharge capacity of these cells is evaluated by galvanostatic cycling, using cutoff potentials of 4.2V vs. Li/Li+ for charge and 3.0 V vs. Li Li+ for discharge. Cycling is performed a C/10 for three cycles, C/2 for 5 cycles, 1C for five cycles, 5C for five cycles, 8C for five cycles, IOC for 5 cycles, C/2 for 5 cycles and C/10 for 5 cycles, for a total of 38 charge/discharge cycles.
  • Solution B is indicated by reference numeral B; those for the half-cells containing
  • Battery Electrolyte Solutions 4-6 are indicated by reference numerals 4-6, respectively.
  • Comparative Sample C exhibits three endothermic peaks (indicated as A, B and C in Figure 6A) in the temperature range from 20 to 350°C, the lowest of these having onset temperatures of about 203°C. Peak endotherms are seen at about 222°C, 258°C and 269°C; total endothermic heat is 368 J/g.
  • Example 7 exhibits only two endothermic peaks (indicated as A and B in Figure 6B). The first of these has an onset temperature of about 227°C. Peak endotherms are seen at 234°C and 263°C, and total endothermic heat is only 134 J/g. The higher onset temperature, higher peak temperatures and lower total endothermic heat all indicate that the presence of the phosphite compound substantially increases the thermal stability of the fully charged cathode in the electrolyte solution.
  • the thermal stability of a fully charged MCMB electrode (85% mesocarbon microbeads, 10% conductive carbon and 5% polytetrafluoroethene) is evaluated in the same manner, in each of the same two battery electrolyte solutions (Comparative Sample C and Example 7).
  • the DSC scans for Comparative Sample C and Example 7 are show in Figures 7A and 7B, respectively.
  • Comparative Sample C three endothermic peaks (indicated as A, B and C in Figure 7A) are seen, with the lowest of these having an onset temperature of 124°C.
  • the three peaks have peak temperatures of about 133°C, 210°C and 310°C; total endothermic heat is 381 J/g.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Manufacturing & Machinery (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Electrochemistry (AREA)
  • General Chemical & Material Sciences (AREA)
  • Physics & Mathematics (AREA)
  • Condensed Matter Physics & Semiconductors (AREA)
  • General Physics & Mathematics (AREA)
  • Inorganic Chemistry (AREA)
  • Secondary Cells (AREA)

Abstract

Cette invention concerne une solution électrolytique pour batterie, contenant de 0,1 à 10% en poids d'un composé de phosphite de tri(aryle substitué par un alkyle). Ledit composé de phosphite de tri(aryle substitué par un alkyle) assure une stabilité thermique accrue à l'électrolyte, encourageant ainsi la réduction de la dégradation thermique, des réactions d'emballement thermiques et des risques de combustion. Ledit composé de phosphite de tri(aryle substitué par un alkyle) ne porte aucune ou quasiment aucune atteinte aux propriétés électriques de la batterie et, dans certains cas, il améliore même la performance de la batterie.
PCT/CN2011/075941 2011-06-20 2011-06-20 Solutions électrolytiques pour batterie contenant des composés de phosphites aromatiques Ceased WO2012174704A1 (fr)

Priority Applications (1)

Application Number Priority Date Filing Date Title
PCT/CN2011/075941 WO2012174704A1 (fr) 2011-06-20 2011-06-20 Solutions électrolytiques pour batterie contenant des composés de phosphites aromatiques

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
PCT/CN2011/075941 WO2012174704A1 (fr) 2011-06-20 2011-06-20 Solutions électrolytiques pour batterie contenant des composés de phosphites aromatiques

Publications (1)

Publication Number Publication Date
WO2012174704A1 true WO2012174704A1 (fr) 2012-12-27

Family

ID=47421970

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/CN2011/075941 Ceased WO2012174704A1 (fr) 2011-06-20 2011-06-20 Solutions électrolytiques pour batterie contenant des composés de phosphites aromatiques

Country Status (1)

Country Link
WO (1) WO2012174704A1 (fr)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2017113820A1 (fr) * 2015-12-31 2017-07-06 石家庄圣泰化工有限公司 Électrolyte de batterie au lithium-ion à haute tension et large température, son procédé de préparation et son application
CN111584934A (zh) * 2019-02-19 2020-08-25 三星Sdi株式会社 锂二次电池
CN111668543A (zh) * 2020-06-10 2020-09-15 广东金光高科股份有限公司 一种锂离子电池安全添加剂及含该添加剂的磺酸亚胺锂盐电解液

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20070048622A1 (en) * 2005-08-24 2007-03-01 Jae-Gu Yoon Organic electrolytic solution and lithium battery using the same
WO2007109435A2 (fr) * 2006-03-22 2007-09-27 Ferro Corporation Electrolytes non aqueux stabilises pour batteries rechargeables

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20070048622A1 (en) * 2005-08-24 2007-03-01 Jae-Gu Yoon Organic electrolytic solution and lithium battery using the same
WO2007109435A2 (fr) * 2006-03-22 2007-09-27 Ferro Corporation Electrolytes non aqueux stabilises pour batteries rechargeables

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2017113820A1 (fr) * 2015-12-31 2017-07-06 石家庄圣泰化工有限公司 Électrolyte de batterie au lithium-ion à haute tension et large température, son procédé de préparation et son application
CN111584934A (zh) * 2019-02-19 2020-08-25 三星Sdi株式会社 锂二次电池
CN111584934B (zh) * 2019-02-19 2023-08-04 三星Sdi株式会社 锂二次电池
CN111668543A (zh) * 2020-06-10 2020-09-15 广东金光高科股份有限公司 一种锂离子电池安全添加剂及含该添加剂的磺酸亚胺锂盐电解液
CN111668543B (zh) * 2020-06-10 2021-11-16 广东金光高科股份有限公司 一种锂离子电池安全添加剂及含该添加剂的磺酸亚胺锂盐电解液

Similar Documents

Publication Publication Date Title
EP2382683B1 (fr) Solutions électrolytiques pour batteries contenant des composés phosphorés aromatiques
JP5886870B2 (ja) 所定のエステルベースの溶媒を含有する電解質溶液および当該電解質溶液を含有する電池
JP6230989B2 (ja) 非水電解質溶液およびその非水電解質溶液を含む電気化学セル
JP2022539947A (ja) 再充電可能なバッテリーセル用のｓｏ２ベースの電解質および再充電可能なバッテリーセル
KR101608844B1 (ko) 비수 전해질 2차 전지 및 비수 전해질 2차 전지의 제조 방법
CN102823051B (zh) 含磷-硫化合物的电池电解质溶液
CN106165182A (zh) 含有二羧酸的酯的电解质组合物
WO2015183597A1 (fr) Solution électrolytique de batterie au lithium contenant du carbonate d'éthyle (2,2,3,3-tétrafluoropropyl)
JP2022551058A (ja) リチウム二次電池用非水電解液及びそれを含むリチウム二次電池
WO2015183598A1 (fr) Solution électrolytique de batterie au lithium contenant du carbonate de (2,2-difluoroéthyl)éthyle
WO2018224167A1 (fr) Batterie au lithium dans laquelle est utilisé de l'oxyde de triphénylphosphine comme additif d'électrolyte
WO2012174704A1 (fr) Solutions électrolytiques pour batterie contenant des composés de phosphites aromatiques
JP2019121611A (ja) リチウムイオン二次電池用電解液及びリチウムイオン二次電池
CN116195109A (zh) 用于锂二次电池的非水电解质和包括该非水电解质的锂二次电池
WO2019202086A1 (fr) Composition d'électrolyte pour batterie au lithium-ion et batterie au lithium-ion
US20240322241A1 (en) Electrolyte Solution for Lithium Secondary Battery and Lithium Secondary Battery Comprising the same
CN120419007A (zh) 锂二次电池用电解质及包括该锂二次电池用电解质的锂二次电池
US20170187062A1 (en) Lithium battery electrolyte solution containing methyl (2,2,3,3,-tetrafluoropropyl) carbonate

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 11868114

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 11868114

Country of ref document: EP

Kind code of ref document: A1