• 专利附录
  • 专利说明
  • 权利要求
  • 类似技术
  • 同族专利
  • 引用文献
  • 法律状态
  • 优先权
    • 专利摘要:
    The present invention relates to the use of at least one compound as an additive in an ion-circulation battery electrolyte, said compound comprising at least one 1,1-dicyanovinyl moiety.
    公开号:FR3038455A1
    申请号:FR1556222
    申请日:2015-07-01
    公开日:2017-01-06
    发明作者:Coralie Forestier；Sylvie Grugeon；Stephane Laruelle；Michel Armand；Lucas Sannier；Laura Coser
    申请人:Centre National de la Recherche Scientifique CNRS；Renault SAS；Universite de Picardie Jules Verne；
    IPC主号:
    专利说明:

    Compound used as an additive in an ion exchange battery electrolyte
    The present invention relates to a compound used as an additive in an ion-circulation battery electrolyte, to an electrolyte comprising said compound, to said electrolyte used in an ion-circulation battery, and to a battery comprising said electrolyte.
    It typically, but not exclusively, applies to the fields of batteries operating with lithium ions (Li +) or sodium ions (Na +), as an electrochemical vector. By way of example, mention may be made of lithium-ion (Li-ion), sodium-ion (Na-ion), lithium-air (Li-air) and lithium-sulfur (Li-sulfur) batteries.
    The batteries are energy storage devices such as electrochemical generators operating on the principle of electrochemical cells connected in series or in parallel, capable of delivering an electric current, thanks to the presence, in each of them, of a pair of electrodes (at least one positive electrode and at least one negative electrode) separated by an electrolyte, the electrodes being made of specific materials able to react together in an oxidation-reduction reaction to produce electrons at the origin electrical current and produce ions that will flow from one electrode to the other through an electrolyte.
    The generators may be more particularly lithium or sodium generators, operating on the principle of insertion-deinsertion of lithium or sodium, respectively. These include Li-ion batteries or Na-ion batteries, respectively.
    In Li-ion batteries, the liquid electrolyte is an essential component that determines the performance and safety of the system. The organic solvents of the electrolyte are known to be reduced during the first charge of the battery and form a protective layer, called passivation, on the surface of the negative electrode, called "Solid Electrolyte Interphase" (SEl).
    This layer, by preventing the subsequent degradation of this electrolyte, thus allows the system to operate. Reinforcement of this layer is thus essential to ensure its protective nature throughout the life cycle of the battery and to limit the loss of capacity during the first charge / discharge cycle.
    Many efforts are made to find the molecules capable of reducing before the solvents and create a more protective layer vis-à-vis the degradation of the electrolyte, and also more resistant to an increase in temperature. By way of example, mention may be made of WO2015033619 which describes a secondary battery comprising a positive electrode, a negative electrode, and a non-aqueous electrolyte composed of a lithium salt dissolved in a non-aqueous solvent and a linear dinitrile compound of NC- (CH 2) n-CN type, "n" being an integer greater than or equal to 1.
    However, this type of compound does not make it possible to obtain a sufficiently protective layer SEI within a battery operating by ion circulation.
    The object of the present invention is to overcome the disadvantages of the techniques of the prior art by proposing the use of a compound as an additive for battery electrolyte operating by ion circulation, to form an optimizing passivation layer including the operation of said battery by decreasing the loss of capacity during the first charge / discharge cycle.
    The present invention relates to a use of at least one compound as an additive in a battery electrolyte operating by ion circulation, said compound comprising at least one 1,1-dicyanovinyl group.
    Thanks to the invention, a battery comprising said additive (ie the compound of the invention used as an additive) in its electrolyte has the advantage of significantly limiting, or even avoiding the loss of capacity during cycling as well as the thermal runaway at the negative electrode / electrolyte interface. The additive advantageously makes it possible to form a passivation layer prior to the reduction of the solvent (s) contained in the electrolyte. The additive
    The compound used as an additive, or in other words the additive, comprises at least one 1,1-dicyanovinyl group.
    In other words, the 1,1-dicyanovinyl group is an α, β-unsaturated dinitrile group in which the two nitrile functions, or more particularly the two cyano functions, are both borne by one of the two carbons of the unsaturation (ie carbon a).
    Preferably, the 1,1-dicyanovinyl group is a 1,1-dicyanovinyl-2,2-disubstituted group in which at least one of the two substituents (in position 2) is an ether group. The additive of the invention may be more particularly chosen from a compound A, a compound B, and a mixture thereof, the compound A being represented by the following formula:
    wherein R is a group selected from an optionally substituted alkylene group; an alkenylene group, optionally substituted; an optionally substituted haloalkylene group; and an optionally substituted haloalkenylene group; and X is selected from an oxygen atom, a nitrogen moiety, and an alkylene moiety; the compound B being represented by the following formula:
    wherein R1 and R2 are the same or different groups selected from linear or branched alkyl groups; linear or branched alkenyl groups; linear or branched haloalkyl groups; and linear or branched haloalkenyl groups; and X is selected from an oxygen atom, a nitrogen moiety, and an alkylene moiety.
    The haloalkylene, haloalkenylene, haloalkyl and haloalkenyl groups may be respectively fluoroalkylene, fluoroalkenylene, fluoroalkyl and fluoroalkenyl groups.
    The group R can be a C2-C10 group, and preferably a C2-C5 group. By way of example, the group R can be chosen from the groups -CH2-CH2-, -CH2-CH2-CH2- and -CH (CH3) -CH2-.
    The group R 1 and / or R 2 can be a C 1 -C 10, and preferably C 2 -C 5, group. By way of example, the group R 1 and / or R 2 can be chosen from the groups -CH 2 -CH 3, -CH 2 -CH 2 -CH 3 and -CH (CH 3) -CH 3.
    When X is a nitrogen group, the latter may be a group of the N-R 'type with R' chosen from a hydrogen atom; a linear or branched alkyl group; and a linear or branched alkenyl group. The group R 'may preferably be a C1-C10 group, and preferably a C1-C5 group.
    When X is an alkylene group, the latter is preferably a -CH 2 - group.
    In a particularly preferred embodiment, the additive is a nonionic compound. The Electrolyte
    Another subject of the invention relates to an electrolyte, or in other words an electrolyte composition, comprising at least one solvent, and at least one alkali metal salt, characterized in that the electrolyte furthermore comprises at least one a compound as an additive, said compound being as defined in the present invention, and / or a reaction product thereof. The electrolyte of the invention can be advantageously used in a battery operated by ion circulation.
    The solvent (s) and the alkali metal salt (s) of the electrolyte may be those conventionally used in Li-ion, Li-sulfur, Li-air or sodium-ion batteries.
    By "one of its reaction products" is meant the reduced form of the additive of the invention. The reduced form of said additive can be obtained either by supply of electrons during the first charging of the battery, or by a redox reaction with lithium metal.
    More particularly, in the Li-ion or Na-ion type batteries, as long as the first charge of the battery has not been carried out, the electrolyte comprises only the additive of the invention in unreduced form.
    In Li-sulfur or Li-air type batteries comprising lithium metal, the electrolyte comprises the additive of the invention in unreduced form and / or the additive of the invention in reduced form. The additive in the electrolyte The electrolyte can thus comprise said additive of the invention and / or at least one of the reaction products of the additive of the invention. The electrolyte of the invention may comprise from 0.1 to 10.0% by weight (inclusive) of said additive, preferably from 0.1 to 5.0% by weight (inclusive) of said additive, and preferably particularly preferably from 0.2 to 1.0% by weight (inclusive) of said additive, based on the total weight of the electrolyte.
    In other words, the additive of the invention can be added advantageously to an electrolyte known to those skilled in the art, in the proportions indicated above.
    Solvent
    The solvent of the electrolyte of the invention may be a single solvent or a mixture of several solvents.
    The solvent of the electrolyte may be a liquid solvent, optionally gelled with a polymer, or a polar polymer solvent optionally plasticized with a liquid.
    The solvent of the electrolyte makes it possible in particular to dissolve the salt or salts of an alkali metal, as well as the additive of the invention.
    The solvent is preferably an aprotic solvent. More particularly, the solvent is a polar organic solvent (i.e. non-aqueous solvent). By way of example, the electrolyte of the invention may comprise one or more liquid solvents chosen from: carbonates, in particular cyclic carbonates, such as, for example, ethylene carbonate (EC), propylene carbonate (PC ), butylene carbonate (BC), dimethyl carbonate (DMC), diethyl carbonate (DEC), methyl ethyl carbonate (MEK), dipropyl carbonate (DPC), methyl carbonate and propyl carbonate (MPC), ethyl and propyl carbonate (EPC), vinylene carbonate (VC), or a mixture thereof; esters, such as, for example, methyl acetate, ethyl acetate, n-propyl acetate, dimethyl acetate, methyl propionate, ethyl propionate, a caprolactone, or a mixture thereof; linear or cyclic ethers, such as, for example, dimethoxyethane (DME), methyl ethers of oligoethylene glycols of 2 to 5 oxyethylene units, dioxolane, dioxane, dibutyl ether, a hydrofuran (eg tetrahydrofuran (THF)) or 2-methyltetrahydrofuran (2MeTHF)), or a mixture thereof; ketones, such as, for example, cyclohexanone; alcohols, such as, for example, ethyl alcohol or isopropyl alcohol; nitrites, such as, for example, acetonitrile; nitrates; amides, such as dimethylformamide; sulfones, such as ethyl-methylsulfone, sulfolane, methyl sulfolane; alkylsulphonamides; and partially hydrogenated hydrocarbons.
    Particularly preferred solvents are cyclic carbonates.
    Preferably, the electrolyte of the invention may comprise a mixture of at least two solvents described above.
    The polar polymer solvent may be chosen from solvating polymers, crosslinked or not, with or without ionic groups grafted. A solvating polymer is a polymer which comprises solvating units containing at least one heteroatom selected from sulfur, oxygen, nitrogen and fluorine. As examples of solvating polymers, mention may be made of polyethers of linear structure, comb or block, forming or not a network, based on poly (ethylene oxide), or copolymers containing the ethylene oxide unit or propylene oxide or allylglycidylether, polyphosphazenes, crosslinked networks based on polyethylene glycol crosslinked by isocyanates or networks obtained by polycondensation and carrying groups that allow the incorporation of crosslinkable groups.
    Block copolymers in which certain blocks carry functions which have redox properties can also be mentioned. Of course, the above list is not limiting, and all polymers having solvating properties can be used.
    The solvent of the electrolyte may simultaneously comprise an aprotic liquid solvent chosen from the aprotic liquid solvents mentioned above and a polar polymer solvent comprising units containing at least one heteroatom chosen from sulfur, nitrogen, oxygen and fluorine. By way of example of such a polar polymer, mention may be made of polymers which mainly contain units derived from acrylonitrile, vinylidene fluoride, N-vinylpyrrolidone or methyl methacrylate.
    The proportion of aprotic liquid in the solvent can vary from 2% (corresponding to a plasticized solvent) to 98% (corresponding to a gelled solvent).
    Alkali metal salt
    The alkali metal salt of the invention may be a single alkali metal salt or a mixture of several alkali metal salts.
    The alkali metal salt of the invention is intended to be dissolved in the solvent of the electrolyte: the electrolyte of the invention thus comprises at least one alkali metal salt dissolved in said solvent.
    The alkali metal salt of the invention may be selected from a lithium salt, a sodium salt, and a mixture thereof.
    The lithium salt may be chosen, for example, from LiClO 4, LiPF 6, LiBF 4, LiAsF 6, ϋΙ ΙO 3, lithium salts having a perfluoroalkanesulfonate anion (eg lithium trifluoromethanesulfonate (UCF3SO3)), lithium bis (perfluoroalkanesulfonyl) methane ( eg lithium bis- (trifluoromethanesulfonyl) methane), lithium bis (perfluoroalkanesulphonyl) imide (eg lithium bis (perfluoroethanesulfonyl) imide or lithium bis (trifluoromethanesulfonyl) imide (LiN (CF3SO2) 2 well known as LiTFSI name), lithium bis (fluoromethanesulfonyl) imide (LiN (FSO2) 2), and a mixture thereof.
    The sodium salt may be chosen for example from NaClO 4, NaBF 4, NaPF 6, NaNO 3, sodium salts having a perfluoroalkanesulfonate anion, sodium bis (perfluoroalkanesulfonyl) methane, sodium tris (perfluoroalkanesulfonyl) methane, bis ( sodium perfluoroalkanesulfonyl) imide (eg sodium bis (trifluoromethanesulfonyl) imide (NaN (CF3SO2) 2 well known as NaTFSI)), sodium bis- (fluoromethanesulfonyl) imide (NaN (FSO2) 2), and one of their mixtures.
    Battery
    Another object of the invention relates to a battery operating by ion circulation, comprising at least one electrochemical cell comprising: at least one positive electrode, at least one negative electrode, and an electrolyte between said positive electrode and said negative electrode, characterized in that said electrolyte is as described in the present invention.
    The battery according to the invention may comprise one or more electrochemical cells, said electrochemical cell comprising said negative electrode and said positive electrode separated by said electrolyte.
    When the battery comprises several electrochemical cells, the electrochemical cells can be assembled in series and / or in parallel.
    In a particular embodiment, the battery may further comprise at least one separator and / or at least one current collector, these elements being well known to those skilled in the art.
    More particularly, the positive electrode may be associated with at least one first collector, and the negative electrode may be associated with at least one second collector.
    The battery of the invention is more particularly a battery called "secondary" or in other words, a rechargeable battery.
    The battery of the invention may be of different types, namely for example of the Li-ion, Na-ion, Li-air or Li-sulfur type, these four types of battery being well known to those skilled in the art. Positive electrode
    By positive electrode is conventionally meant the electrode which acts as a cathode, when the battery delivers current (that is to say when it is in the process of discharge) and which acts as anode when the battery is in charging process. The positive electrode may be that typically used in Li-ion, Na-ion, Li-air, or Li-sulfur batteries. The positive electrode is typically formed from a composite material comprising at least one positive electrode active material, optionally an electronic conduction agent, and optionally a binder. The positive electrode active material is a material capable of reversibly inserting ions. As an example for Li-ion batteries, the content of positive electrode active material of said composite material may be from 5 to 98% by weight, the content of electronic conduction agent may be from 0.1 to 30% by weight, and the binder content may be from 0 to 25% by weight, based on the total weight of composite material.
    In a first embodiment specific to Li-ion batteries, the positive electrode active material is in particular capable of reversibly inserting lithium ions at a potential greater than the operating potential of the negative electrode.
    The active material may include in particular a number of oxides well known to those skilled in the art. As an example of active material, there may be mentioned manganese dioxide (MnO 2); iron oxide; copper oxide; nickel oxide; lithium-manganese composite oxides (e.g., LixMn204 or LixMnO2); lithium-nickel composite oxides (e.g., LixNiO 2); lithium-cobalt composite oxides (e.g., LixCoO2); lithium-nickel-cobalt composite oxides (e.g. LiNi 2-yCOyO 2); lithium-nickel-cobalt-manganese composite oxides (e.g., UnixMnyCOzO 2 with x + y + z = 1); lithium-nickel-cobalt-manganese composite oxides enriched in lithium (e.g. Lii + x (NiMnCo) i-xO2); composite oxides of lithium and transition metal; lithium-manganese-nickel composite oxides of spinel structure (e.g., LixMn2_yNiyO4); lithium-phosphorus oxides of olivine structure (e.g. LixFeP04, LixFei-yMnyP04 or LixCoP04); iron sulphate (Fe2 (SO4) 3); vanadium oxides (e.g., V2Os).
    The composite oxides of lithium and of transition metal may be the following composite oxides: Li (Ni, Co, Mn) O 2 well known under the name NMC, such as, for example, Li (Nii / 3Mni / 3Coi / 3) O 2; Li (Ni, Co, Al) 2, which is well known under the name NCA, such as, for example, Li (NiO, CaCOO, AlAl, OO) O; or - Li (Ni, Co, Mn, Al) 02. The electronic conduction agent may be a carbonaceous material, for example carbon black, acetylene black, natural or synthetic graphite, carbon nanotubes, or a mixture thereof.
    The binder can be a polymer chosen, for example, from ethylene and propylene copolymers optionally containing a unit that allows crosslinking; styrene-butadiene copolymers, such as, for example, styrene-butadiene rubbers (SBR); acrylonitrile-butadiene copolymers (ABR); poly (tetrafluoroethylene), such as, for example, polytetrafluoroethylene (PTFE) or polyvinylidene difluoride (PVDF); cellulose derivatives, such as, for example, carboxymethyl cellulose (CMC) or hydroxyethylcellulose (HEC).
    In a second embodiment specific to Na-ion batteries, the positive electrode active material is in particular capable of reversibly inserting sodium ions at a potential greater than the operating potential of the negative electrode. As an example of an active ingredient, there may be mentioned lamellar fluorophosphates Na2TP04F in which T represents a divalent element chosen from Fe, Mn, Co, and Ni, which may be partially replaced by Mg or Zn; fluorophosphates different from the above fluorophosphates, said fluorophosphates being selected from Na3V2 (PO4) 2F3, Na3V2 (PO4) 3 and NaVPO4F; the fluorosulphates NaT'SO 4 F in which T 'represents at least one element selected from Fe, Mn, Co, V and Ni, part of which may be replaced by Mg and part of the sulfate groups SO42' may be replaced by the isocyanate group; stere and iso-charge P03F2 '; polysulfides Na2Sn (1 <n <6), and sodium salts of dimercaptothiadiazole and dimercaptooxazole; the dithiocarbamates Na [CS2NR'R "] in which each of the groups R 'and R" represents a methyl, ethyl or propyl radical, or else R' and R "forming a ring (for example pyrrolidine or morpholine). The electronic conduction agent and the binder may be those described above for the positive electrode Li-ion battery.
    In a third embodiment specific to Li-air batteries, the positive electrode is made of carbon, in particular porous, and optionally of a catalyst, such as a metal oxide of the MnO 2 or Mn 2 O 4 type, in finely divided form.
    In a fourth embodiment specific to Li-sulfur batteries, the positive electrode consists of elemental sulfur mixed with carbon, preferably absorbed in the pores of a mesocarbon. The negative electrode
    By negative electrode is conventionally meant the electrode which acts as anode, when the battery discharges the current (that is to say when it is in the process of discharge) and which acts as a cathode, when the battery is in the process of charging. The negative electrode may be that typically used in Li-ion, Na-ion, Li-air, or Li-sulfur batteries. The negative electrode is typically formed from a composite material comprising at least one negative electrode active material, optionally an electronic conduction agent, and optionally a binder. The negative electrode active material is a material capable of reversibly inserting ions. As an example for Li-ion batteries, the content of negative electrode active material of said composite material can be at least 60% by weight, the content of electronic conduction agent can be from 0 to 30% by weight. weight, and the binder content may be 0 to 30% by weight, based on the total weight of composite material.
    In a first embodiment specific to Li-ion batteries, the negative electrode active material may be a material capable of reversibly inserting lithium ions.
    This material may in particular be a hard carbon, a soft carbon, an intermediate hardness carbon, a natural or artificial graphite, a lithium dicarboxylate (in particular lithium terephthalate). The active material may also be a lithium alloy (for example a silicon-lithium or lithium-lithium alloy) or another lithium intermetallic compound (for example the compound LiAI), a lithium titanate of the type ϋ4Τί50ι2 or TiO2, optionally doped with Mg, or molybdenum dioxide or tungsten. When the negative electrode material contains a Li alloy or lithium intermetallic compound as the active material, it necessarily contains an electronic conduction agent. The electronic conduction agent and the binder can be respectively those described above for the positive electrode of the Li-ion battery.
    In a second embodiment specific to Na-ion batteries, the negative electrode active material is a material capable of reversibly inserting sodium ions.
    This material may in particular be a mesoporous carbon, a sodium dicarboxylate (in particular sodium terephthalates), a sodium ferrite NaxFeO 2, a sodium titanate Na 2 + x TiO 3 O (0 <x '<2), a sodium titanate and a sodium titanate. aluminum NaxTii_zAlzO2 (0 <x <1, 0 <z <0.4) of lamellar structure, also referred to as "hollandite", or of a sodium alloy, for example a tin-sodium alloy or a lead-sodium alloy. The electronic conduction agent and the binder may be those described above for the positive electrode of the Li-ion battery.
    In a third embodiment specific to Li-air batteries, the negative electrode is made of lithium metal.
    In a fourth embodiment specific to Li-sulfur batteries, the negative electrode is made of lithium metal.
    The separator
    The separator is conventionally positioned between the positive electrode and the negative electrode, thereby preventing the positive electrode from being in direct physical contact with the negative electrode. The separator is conventionally an electrically insulating material.
    The separator may be advantageously impregnated and / or covered with electrolyte.
    It is characterized by a high wettability with the electrolyte, in particular it preferably has an angle of contact with the electrolyte, less than 20 °.
    More particularly, the separator may be a nonwoven material such as polymer fibers, or a porous material such as a polymeric material disposed in one or more layers.
    The polymer may be chosen for example from polyethylene (PE), polypropylene (PP), polyimides (PI), polyethylene terephthalate (PET), and a mixture thereof.
    In a particular embodiment, the porous polymeric material may be a trilayer composed of a polyethylene layer interposed between two layers of polypropylene. Other materials well known to those skilled in the art can of course be used such as separators covered with ceramic or polyaramid-based compounds (PAI) or a ceramic / PAI mixture.
    The current collector
    The electrode material may be carried by a current collector. In a particular embodiment, the two faces of the current collector may be covered with the electrode material: this is called a double-sided electrode.
    The current collector may consist of a conductive material, in particular a metallic material which may be chosen for example from copper, a copper alloy, aluminum, an aluminum alloy, iron, and a metal alloy. iron (eg steel). Other features and advantages of the present invention will become apparent in the light of the description of non-limiting examples of the use of an additive according to the invention.
    FIG. 1 represents the evolution of the capacity as a function of the number of cycles, for an electrolyte comprising the additive of the invention and for an electrolyte not comprising said additive, at a temperature of 20 ° C.
    FIG. 1b shows the evolution of the capacity as a function of the number of cycles, for an electrolyte comprising the additive of the invention and for an electrolyte not comprising said additive, at a temperature of 45 ° C.
    FIG. 2a represents the relative abundance of the compound I1 resulting from the degradation of the electrolyte during cycling, for an electrolyte comprising the additive of the invention and for an electrolyte not comprising said additive, cycled at a temperature of 20 ° C.
    FIG. 2b represents the relative abundance of the compound 1i resulting from the degradation of the electrolyte during cycling, for an electrolyte comprising the additive of the invention and for an electrolyte not comprising said additive, cycled at a temperature of 45 ° C.
    FIG. 3a represents the evolution of the heat flux released at the lithiated graphite / electrolyte interface as a function of temperature, for an electrolyte comprising the additive of the invention and for an electrolyte not comprising said additive, cycled at a temperature of temperature of 20 ° C.
    FIG. 3b represents the evolution of the heat flux released at the lithiated graphite / electrolyte interface as a function of temperature, for an electrolyte comprising the additive of the invention and for an electrolyte not comprising said additive, cycled to a temperature of 45 ° C.
    Exem pies
    In order to show the advantages of the present invention, an electrochemical cell has been produced and comprises the following successive layers: a first current collector, a positive electrode, a separator impregnated with an electrolyte, a negative electrode, and a second current collector. All of these five elements form a multilayer system. The electrolyte of the electrochemical cell, which impregnates the separator, is either an electrolyte II according to the invention or an electrolyte C1 as a comparative example, the electrolytes II and C1 being described below.
    The electrochemical cell is positioned inside a flexible envelope-type aluminum container, well known under the anglicism "pouch cell". The Positive Electrode The positive electrode is formed from a composite material comprising 94% by weight of NMC of formula ϋ (Νΐι / 3Μηι ^ θι / 3) 02 as positive electrode active material, 3% by weight. weight of carbon as an electronic conduction agent, and 3% by weight of PVDF as binder, based on the total weight of composite material. The positive electrode forms a layer with a thickness of 60 μm.
    It is associated with an aluminum current collector 20 μm thick. The negative electrode The negative electrode is formed from a composite material comprising 94% by weight of graphite as a negative electrode active material, 2% by weight of carbon as an electronic conduction agent, and 4% by weight of a 50/50 mixture (% by weight) of CMC and SBR as binder, based on the total weight of composite material. The negative electrode forms a layer with a thickness of 60 μm.
    It is associated with a 10-μm thick copper current collector.
    The separator
    The separator is a porous polymeric material formed of a layer of polyethylene interposed between two layers of polypropylene.
    The separator formed of these three layers has a thickness of 25 μm.
    Electrolytes II and Cl
    Electrolytes II and Cl are liquid electrolytes. The electrolyte Cl consists solely of a solution comprising 1 mol / l of LiPF 6 as the lithium salt, this salt being dissolved in a solvent comprising a 50/50 mixture (% by weight) of EC and DMC. The electrolyte II comprises the electrolyte C1 in which 0.5% by weight of the additive of the invention has been added, relative to the total weight of the electrolyte II. The additive of the invention used in this example (see electrolyte II) is the compound Al of the following formula (CAS number 100517-17-7):
    This additive can also be easily synthesized according to the scientific publication of W. J. Middleton and V. A. Engelhardt, J. Am. Chem. Soc. 80, p. 2793, 1958.
    The electrochemical cell is cycled. Each cycle lasts about 10 hours, and includes a charge of about 5 hours and a discharge of about 5 hours. After each charge and after each discharge, a pause or relaxation time of 30 minutes is performed.
    In a first embodiment, 400 cycles are performed at room temperature (20 ° C).
    In a second embodiment, 100 cycles are performed at a temperature above 20 ° C, placing the electrochemical cell in an oven at 45 ° C.
    Different properties were measured and the overall results are grouped together in FIGS. 1a, 1b, 2a, 2b, 3a and 3b.
    FIGS. 1a and 1b show the evolution of the capacity (in milliamperes / hour) as a function of the number of cycles, for the electrolytes II and Cl, at a temperature of 20 ° C. and 45 ° C. respectively.
    The capacity is measured during the cycles, using a multipotentiostat VMP3 (marketed by the company Biology), connected to the electrodes of the electrochemical cell.
    It is clear that the presence of the compound Al in the electrolyte II makes it possible to improve the retention of capacity during the cycling at 20 ° C. as well as at 45 ° C.
    FIGS. 2a and 2b show the relative abundance of the compound I1 resulting from the degradation of the electrolyte during cycling, for the electrolytes II and Cl, after cycling at a temperature of 20 ° C. and 45 ° C. respectively. The relative abundance is measured using a GC / MS chromatograph on the electrolyte after the cycles are complete. More particularly, at the end of the cycles, the electrolyte-impregnated separator is removed from the electrochemical cell, and the electrolyte is then dissolved in a solvent of the acetonitrile type. Finally, a volume of said electrolyte (diluted in acetonitrile) is injected into the chromatograph.
    In the left part of FIGS. 2a and 2b, between the 18th and the 19th minute, is represented the peak of the "li" molecule, which has been magnified 10 times ("x10").
    The molecule called "li" is dimethyl 2,5-dioxahexane dicarboyxlate, which can be found in the scientific publication of G. Gachot et al., Journal of Power Sources 178 (2008), pages 409-421. This molecule is a result of electrolyte degradation processes during cycling and is reported as an indicator of the passivity of SEI.
    It is clear in these figures that the presence of the compound Al in the electrolyte II inhibits the formation of the molecule "li".
    FIGS. 3a and 3b show the evolution of the heat flux (arbitrary unit ua) released at the lithiated graphite / electrolyte interface as a function of temperature (in degrees Celsius), for the electrolytes II and Cl, cycled at a temperature of 20 ° C and 45 ° C respectively.
    The heat flow is measured by differential scanning calorimetry (DSC) with a temperature ramp of 10 ° C / min under an argon atmosphere. The heat energy corresponds to the total energy released at the negative electrode / electrolyte interface, during the DSC measurement (exothermic phenomenon). To do this, at the end of the cycles, the negative electrode (lithiated graphite) in contact with the electrolyte, and in particular containing electrolyte in its pores, is removed from the electrochemical cell. Then, a portion of said electrode is recovered for analysis by DSC.
    FIGS. 3a and 3b show that the presence of the compound Al in the electrolyte II makes it possible to push the thermal runaway process at the negative electrode / electrolyte interface to a higher temperature.
    The compound Al according to the invention, used as an additive in the electrolyte, advantageously makes it possible to form a passivation layer prior to the reduction of the solvents contained in the electrolyte. More particularly, the polarization of the C-O bond of the compound A1 is unexpectedly increased by the presence of the 1,1-dicyanovinyl moiety which contains only less electronegative nitrogen and carbon atoms than oxygen. As a result, the compound A1 can be reduced more easily than, for example, the C-O bond of the ethylene carbonate (EC) used in the solvent mixture.
    Therefore, the presence of the additive according to the invention in a battery electrolyte operating by ion circulation, is particularly beneficial to cycling at 20 and 45 ° C. Indeed, the capacity retention is better and the process of solvent degradation is significantly limited, if not prevented. Likewise, the thermal runaway process at the negative electrode / electrolyte interface is initiated at a higher temperature.
    权利要求:
    Claims (14)
    [1" id="c-fr-0001]
    REVENDI CATI ONS
    Use of at least one compound as an additive in a circulating ion battery electrolyte, said compound comprising at least one 1,1-dicyanovinyl moiety.
    [2" id="c-fr-0002]
    2. Use according to claim 1, characterized in that the 1,1-dicyanovinyl group is a 1,1-dicyanovinyl-2,2-disubstituted group in which at least one of the two substituents is an ether group.
    [3" id="c-fr-0003]
    3. Use according to claim 1 or 2, characterized in that said compound is chosen from a compound A, a compound B, and a mixture thereof, the compound A being represented by the following formula:

    wherein R is a group selected from an optionally substituted alkylene group; an alkenylene group, optionally substituted; an optionally substituted haloalkylene group; and an optionally substituted haloalkenylene group; and X is selected from an oxygen atom, a nitrogen moiety, and an alkylene moiety; the compound B being represented by the following formula:

    in which R 1 and R 2 are identical or different groups chosen from linear or branched alkyl groups; linear or branched alkenyl groups; linear or branched haloalkyl groups; and linear or branched haloalkenyl groups; and X is selected from an oxygen atom, a nitrogen moiety, and an alkylene moiety.
    [4" id="c-fr-0004]
    4. Use according to claim 3, characterized in that the group R is a C2-C10 group.
    [5" id="c-fr-0005]
    5. Use according to claim 4, characterized in that the group R is chosen from the groups -CH2-CH2-, -CH2-CH2-CH2- and -CH (CH3) -CH2-,
    [6" id="c-fr-0006]
    6. Use according to claim 3, characterized in that the group Ri and / or R2 is a group Ci-C10.
    [7" id="c-fr-0007]
    7. Use according to claim 6, characterized in that the group R 1 and / or R 2 is chosen from the groups -CH 2 -CH 3, -CH 2 -CH 2 -CH 3 and -CH (CH 3) -CH 3.
    [8" id="c-fr-0008]
    8. Use according to any one of the preceding claims, characterized in that said compound is nonionic.
    [9" id="c-fr-0009]
    An electrolyte comprising at least one solvent, and at least one alkali metal salt, characterized in that the electrolyte further comprises at least the compound as an additive, said compound being as defined in any one of Claims 1 to 8, and / or one of its reaction products.
    [10" id="c-fr-0010]
    10. Electrolyte according to claim 9, characterized in that it comprises from 0.1 to 10.0% by weight (inclusive) of said compound relative to the total weight of the electrolyte.
    [11" id="c-fr-0011]
    11. Electrolyte according to claim 9 or 10, characterized in that the solvent is an aprotic solvent.
    [12" id="c-fr-0012]
    12. Electrolyte according to any one of claims 9 to 11, characterized in that the alkali metal salt is selected from a lithium salt, a sodium salt, and a mixture thereof.
    [13" id="c-fr-0013]
    13. Use of an electrolyte according to any one of claims 9 to 12 in a battery operated by ion circulation.
    [14" id="c-fr-0014]
    14. Battery operated by ion circulation, comprising at least one electrochemical cell comprising: - at least one positive electrode, - at least one negative electrode, and - an electrolyte between said positive electrode and said negative electrode, characterized in that said electrolyte is as defined in any one of claims 9 to 12.
    类似技术:
    公开号 | 公开日 | 专利标题
    KR20080033883A|2008-04-17|Battery
    JP2008147153A|2008-06-26|Lithium secondary battery
    FR2852148A1|2004-09-10|Composite material for use in the construction of electrochemical batteries and supercapacitors comprising active electrode material, an electroconductive material, an organic binder and a salt
    JP5264271B2|2013-08-14|Non-aqueous electrolyte secondary battery and manufacturing method thereof
    EP3317912B1|2019-04-17|Compound used as additive in an electrolyte for an ion-flow battery
    WO2019054418A1|2019-03-21|Nonaqueous electrolyte additive, nonaqueous electrolyte, and nonaqueous electrolyte battery
    JP2004014134A|2004-01-15|Nonaqueous electrolyte secondary battery and electrolyte used for it
    JP2003007336A|2003-01-10|Nonaqueous electrolytic solution secondary battery and nonaqueous electrolytic solution for use in the same
    CN112335073A|2021-02-05|Negative electrode for lithium secondary battery, method of pre-lithiating the negative electrode, and lithium secondary battery including the negative electrode
    JP2003086248A|2003-03-20|Non-aqueous electrolytic solution secondary battery and electrolytic solution
    CN111095657A|2020-05-01|Additive for nonaqueous electrolyte solution, electrolyte solution for nonaqueous electrolyte solution battery, and nonaqueous electrolyte solution battery
    JP6541873B2|2019-07-10|Electrolyte for lithium secondary battery and lithium secondary battery including the same
    JPWO2014069460A1|2016-09-08|Lithium secondary battery
    EP3647443B1|2021-05-19|Specific negative electrode made of lithium and lithium electrochemical generator including such a negative electrode
    US20200076000A1|2020-03-05|Non-aqueous electrolyte and non-aqueous electrolyte secondary battery
    WO2019097189A1|2019-05-23|Use of a salt mixture as an additive in a lithium-gel battery
    JP2002260726A|2002-09-13|Nonaqueous electrolyte secondary battery
    EP3648206B1|2021-09-15|Lithium electrochemical battery such as lithium-sulphur comprising a specific negative electrode material
    EP2721683B1|2015-07-29|Liquid electrolyte for lithium accumulator, comprising a ternary mixture of non-aqueous organic solvents
    WO2022030109A1|2022-02-10|Lithium ion secondary battery
    FR3095551A1|2020-10-30|Electrolyte for an electrochemical accumulator comprising a particular ionic liquid
    CA3081892A1|2019-05-23|Use of lithium nitrate as the sole lithium salt in a lithium-gel battery
    JP3617494B2|2005-02-02|Nonaqueous electrolyte secondary battery
    CN113728483A|2021-11-30|Nonaqueous electrolyte solution additive, and nonaqueous electrolyte solution for lithium secondary battery and lithium secondary battery containing same
    CN113646944A|2021-11-12|Nonaqueous electrolyte solution for lithium secondary battery and lithium secondary battery comprising same
    同族专利:
    公开号 | 公开日
    KR20180022983A|2018-03-06|
    WO2017001759A1|2017-01-05|
    CN108140878A|2018-06-08|
    KR102039465B1|2019-11-01|
    FR3038455B1|2020-03-13|
    EP3317912A1|2018-05-09|
    EP3317912B1|2019-04-17|
    CN108140878B|2021-03-09|
    引用文献:
    公开号 | 申请日 | 公开日 | 申请人 | 专利标题
    JP2009123499A|2007-11-14|2009-06-04|Sony Corp|Nonaqueous electrolyte secondary battery and nonaqueous electrolyte composition|
    FR2928925A1|2008-03-19|2009-09-25|Centre Nat Rech Scient|BORON OR ALUMINUM COMPLEXES AND THEIR USES.|
    US20130004861A1|2011-06-30|2013-01-03|Jung-Yi Yu|Electrolyte additive for lithium secondary battery, non-aqueous electrolyte, and lithium secondary battery including the same|
    US2980698A|1958-04-25|1961-04-18|Du Pont|Dicyanoketene cyclic acetals and process for preparation|
    SU1273356A1|1985-07-18|1986-11-30|Чувашский государственный университет им.И.Н.Ульянова|Method of producing dicyanketene ketals|
    KR100814540B1|2001-04-06|2008-03-17|발렌스 테크놀로지, 인코포레이티드|Sodium Ion Batteries|
    KR20060075970A|2004-12-29|2006-07-04|주식회사 엘지화학|Lithium secondary battery comprising electrolyte added with nitrile group-containing compound and preparation method thereof|
    US8993177B2|2009-12-04|2015-03-31|Envia Systems, Inc.|Lithium ion battery with high voltage electrolytes and additives|
    PL2605324T3|2010-08-13|2019-06-28|Lg Chem, Ltd.|Non-aqueous electrolyte solution for a lithium secondary battery, and lithium secondary battery comprising same|
    WO2012170240A1|2011-06-07|2012-12-13|3M Innovative Properties Company|Lithium- ion electrochemical cells including fluorocarbon electrolyte additives|
    KR101502656B1|2012-05-08|2015-03-16|주식회사 엘지화학|Non-aqueous electrolyte solution for lithium secondary battery and lithium secondary battery comprising the same|
    KR20160050024A|2013-09-05|2016-05-10|이시하라 산교 가부시끼가이샤|Nonaqueous-electrolyte secondary battery and manufacturing method therefor|CN110797566B|2018-08-03|2021-12-10|惠州市豪鹏科技有限公司|Lithium ion battery electrolyte and lithium ion battery|
    KR20210070609A|2019-12-05|2021-06-15|주식회사 엘지에너지솔루션|Non-aqueous electrolyte for lithium secondary battery and lithium secondary battery comprising the same|
    CN112670579B|2020-12-23|2022-02-25|东莞新能源科技有限公司|Electrolyte solution, electrochemical device, and electronic device|
    法律状态:
    2016-07-21| PLFP| Fee payment|Year of fee payment: 2 |
    2017-01-06| PLSC| Search report ready|Effective date: 20170106 |
    2017-07-24| PLFP| Fee payment|Year of fee payment: 3 |
    2018-07-25| PLFP| Fee payment|Year of fee payment: 4 |
    2019-07-19| PLFP| Fee payment|Year of fee payment: 5 |
    2020-07-21| PLFP| Fee payment|Year of fee payment: 6 |
    2021-07-27| PLFP| Fee payment|Year of fee payment: 7 |
    优先权:
    申请号 | 申请日 | 专利标题
    FR1556222A|FR3038455B1|2015-07-01|2015-07-01|COMPOUND USED AS AN ADDITIVE IN AN ELECTROLYTE FOR ION CIRCULATION BATTERY|
    FR1556222|2015-07-01|FR1556222A| FR3038455B1|2015-07-01|2015-07-01|COMPOUND USED AS AN ADDITIVE IN AN ELECTROLYTE FOR ION CIRCULATION BATTERY|
    PCT/FR2016/051589| WO2017001759A1|2015-07-01|2016-06-28|Compound used as additive in an electrolyte for an ion-flow battery|
    EP16741357.4A| EP3317912B1|2015-07-01|2016-06-28|Compound used as additive in an electrolyte for an ion-flow battery|
    CN201680044722.4A| CN108140878B|2015-07-01|2016-06-28|Compound used as additive in electrolyte of ion cycle battery|
    KR1020187003224A| KR102039465B1|2015-07-01|2016-06-28|Compounds used as additives in electrolytes for ion-cycle batteries|
    [返回顶部]