• 专利附录
  • 专利说明
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  • 优先权
    • 专利摘要:
    The present invention relates to a lithium-ion battery comprising: - a positive electrode comprising a positive electrode active material, and advantageously a lithium salt; an electrolyte comprising a lithium salt; a negative electrode comprising a negative electrode active material, and advantageously a lithium salt. In this battery, the positive electrode, the negative electrode and the electrolyte are all in the form of gels, and all three comprise a polymer and a dinitrile compound of formula N≡C-R-C≡N; R being a CnH2n hydrocarbon group, n being an integer between 1 and 2; the dinitrile / polymer compound weight ratio being between 60/40 and 90/10.
    公开号:FR3040550A1
    申请号:FR1557896
    申请日:2015-08-25
    公开日:2017-03-03
    发明作者:Sebastien Solan；Laura Boutafa；Lionel Picard；Angele Ravachol
    申请人:Commissariat a lEnergie Atomique CEA；Commissariat a lEnergie Atomique et aux Energies Alternatives CEA；
    IPC主号:
    专利说明:

    LITHJTIM-TON GELIFIEE BATTERY FIELD OF THE INVENTION
    The present invention relates to a lithium battery whose electrodes and electrolyte are in the form of gels. The gel electrodes and the gel electrolyte comprise at least one polymer and a dinitrile compound.
    The field of use of the present invention relates in particular to the storage of energy.
    PRIOR STATE OF THE TECHNIQUE
    In general, a lithium-ion battery comprises the following elements: a current collector of the positive electrode; a positive electrode comprising a lithium cation insertion material; an electrolytic constituent; a negative electrode; a current collector of the negative electrode; a flexible packaging or a rigid case.
    The insertion material of the lithium cation of the positive electrode is generally a composite material, for example lithium iron phosphate, LiFePCL, or a transition metal oxide (lamellar materials: L1COO2: lithiated cobalt oxide,
    LiNio.33Mno.33Coo.33O2 ...).
    The electrolytic constituent separating the electrodes of opposite signs, is generally composed of a polymer separator or a microporous composite impregnated with organic electrolyte. The separator provides the mechanical strength, while the electrolyte ensures the displacement of lithium ions from the positive electrode to the negative electrode and vice versa (case of charging or discharging) thus generating the current. The electrolyte generally comprises a solvent and a lithium salt such as LiPF6. It is preferably free of traces of water or oxygen.
    The negative electrode material is generally graphite carbon, silicon or in the case of power electrodes titanate material (Li4Ti50i2).
    The electrodes and the electrolytic constituent form the electrochemical core of the battery. The current collectors are generally integral with the electrodes and can therefore be an integral part of the electrochemical core.
    The current collector of the positive electrode is generally aluminum, while the current collector of the negative electrode is generally copper for a negative carbon graphite electrode, or aluminum for a titanate negative electrode.
    Typically, a battery may comprise a plurality of electrochemical cores in the form of a stack, in particular a stack facing each other (flat or wound stack).
    Depending on the applications concerned, the packaging of the battery can be flexible or rigid.
    As already stated, the presence of an electrolyte makes it possible to ensure the displacement of the lithium ions between the electrodes of opposite signs. During the preparation of a battery, the insertion of the electrolyte into the battery core can be achieved by: placing the electrochemical core and the current collectors in a pouch constituting the package, tabs connected to the collectors current out of this pouch so as to ensure the recovery of current; introducing a liquid electrolyte into the pouch; sealing the package, generally by heat sealing, to seal the electrochemical core. The introduction of the electrolyte therefore requires the use of a liquid electrolyte which impregnates an electrode separator. In this regard, CA 2 435 218 discloses the use of dinitrile solvent to form a liquid electrolyte containing lithium salts. In addition, the documents WO 2007/012174 and WO 2008/138110 describe the use of dinitrile solvent to form an electrolyte supported by a microporous separator of polyolefin type.
    Even though the insertion of a liquid electrolyte makes it possible to prepare batteries satisfactorily, there is a need to simplify this process, in particular by using a solid electrolyte. On the other hand, in the field of flexible batteries, the improvement of the flexibility of the electrolytic component (separator + electrolyte) and electrodes is also sought.
    The present invention addresses these problems through the development of a battery whose electrochemical core (electrolytic component + electrodes) is gelled. This battery comprises a gel electrolyte allowing in particular to overcome the use of a conventional separator soaked with liquid electrolyte.
    SUMMARY OF THE INVENTION
    The present invention relates to a lithium-ion battery whose electrochemical core (electrolyte + electrodes) is in gelled form, thus providing flexibility properties to the battery. Because of its gelled form, this battery does not include free solvent.
    In the battery according to the invention, the gelled form of the electrolyte does not alter the ionic conductivity properties necessary for its proper operation. It is the same for gelled electrodes, whose performance is comparable to that of conventional solid electrodes.
    The gelled form of the electrolyte and the electrodes also makes it possible to improve the properties relating to the safety and the flexibility of the battery.
    More specifically, the present invention relates to a lithium-ion battery comprising: a positive electrode comprising a positive electrode active material, and preferably a lithium salt; an electrolyte comprising a lithium salt; a negative electrode comprising a negative electrode active material, and preferably a lithium salt.
    In this lithium-ion battery, the positive electrode, the negative electrode and the electrolyte are all in the form of gels, and all three comprise a polymer and a dinitrile compound of formula N = C-R-C = N; R being a CnH2n hydrocarbon group, n being an integer between 1 and 2; the mass ratio of the dinitrile / polymer compound being between 60/40 and 90/10.
    In other words, the battery according to the invention comprises: a positive electrode in the form of a gel comprising a positive electrode active material, a polymer, a dinitrile compound, and advantageously a lithium salt; a gel electrolyte comprising a lithium salt, a polymer and a dinitrile compound; a negative electrode in the form of a gel comprising a negative electrode active material, a polymer, a dinitrile compound, and advantageously a lithium salt. Since the electrolyte is in the form of a gel, the battery according to the invention does not require a conventional separator. The gel electrolyte allows both the displacement of the lithium ions and the function of the electrode separator.
    The dinitrile compound used has a melting point advantageously greater than 20 ° C., thus facilitating the manipulation of the electrolyte and the electrodes during the preparation of the battery according to the invention. The dinitrile compound corresponds to the solvent of the electrolytic medium. This one forms the same medium within the set of compartments of the battery.
    Advantageously, the dinitrile compound is succinonitrile (n = 2) or malononitrile (n = 1).
    According to a particular embodiment, the dinitrile compound used to prepare the three constituents "gel" (electrodes + electrolyte) of the electrochemical core of the battery according to the invention is succinonitrile.
    Succinonitrile is a non-flammable, non-volatile, hyper-plastic crystalline organic compound (boiling point 266 ° C) having a melting point of 57 ° C. Its potential temperature range of use is between -20 ° C and 250 ° C. By way of example, an IM solution of LiTFSi salt in succinonitrile has an ionic conductivity of the order of 3.10 -3 S.cm-1 at 20 ° C.
    In general, the dinitrile compound makes it possible in particular to solubilize the lithium salt of the electrolyte and possibly electrodes. In addition, its combination with a polymer makes it possible to obtain a gel.
    To obtain a gel, the dinitrile / polymer mass ratio is between 60/40 and 90/10, more advantageously between 65/35 and 75/25, and even more advantageously of the order of 70/30.
    The polymer used in the invention is advantageously chosen from the group comprising poly (styrene-co-acrylonitrile); poly (butyl methacrylate-co-isobutyl methacrylate); poly (butyl methacrylate); poly (isobutyl methacrylate); poly (butyl methacrylate-co-methyl methacrylate); poly (methyl methacrylate) (PMMA); poly (vinylidene fluoride-hexafluoropropylene) (PVdF-HFP); polyethylene oxide (POE); and polyvinylpyrrolidone (PVP).
    The lithium salt used in the electrolyte, and optionally in the positive electrode and / or the negative electrode, is advantageously chosen from the group comprising LiTFSi (lithium bis-trifluoromethanesulfonimide); LiBOB (lithium bis (oxatlato) borate); LiPF6; LiCICL; L1BF4; LiAsF6; L1CF3SO3; LiN (CF3SO2) 3; LiN (C2F5SO2); and their mixtures.
    In the electrolyte, the concentration of lithium salt is advantageously between 0.5 and 5M in the dinitrile compound, more advantageously of the order of 1M in particular.
    In addition, the weight ratio [dinitrile compound + lithium salt] / [olymer] is advantageously between 60/40 and 90/10, more preferably of the order of 70/30. This ratio makes it possible to maintain adequate properties in terms of ionic conductivity provided by the mixture [dinitrile compound + lithium salt] and mechanical strength provided by the polymer.
    Advantageously, the positive electrode, the negative electrode and the electrolyte of the battery according to the invention comprise the same polymer and / or the same dinitrile compound and / or the same lithium salt.
    Even more advantageously, the positive electrode, the negative electrode and the electrolyte (electrolyte separator formed by a polymer membrane gelled by the dinitrile electrolyte / lithium salt) of the battery according to the invention comprise the same polymer, the same dinitrile compound, and the same lithium salt.
    The active materials of the positive and negative electrodes that can be used in the battery according to the invention correspond in particular to the conventional materials described in the literature (Tarascon et al., Nature, 2001, 414, 359-367). By way of example, mention may be made in particular of:
    LiFePCL (LFP) and LiNi0.33Mno.33Coo.33O2 (NMC) for the positive electrode; and titanate Li4Ti50i2 (LTO), graphite carbon; sulfur ; lithium metal; and silicon for the negative electrode.
    The active material may represent 50 to 95%, relative to the mass of the electrode (positive or negative), more preferably 80 to 70%.
    In general, a silicon active material (negative electrode) undergoes significant volumetric deformation during charge and discharge cycles, unlike LFP, NMC or LTO type materials. This deformation can reach 300% between the fully charged state and the fully discharged state, thus causing the progressive destruction of the electrode structure. Therefore, a conventional silicon-based electrode has a limited life. The present invention also solves this problem, the gelled form makes it possible to adapt the mechanical properties of the electrodes to compensate for variations in volume, without compromising the structure of the electrode.
    In addition to the active material, the electrodes advantageously comprise at least one electronic conductor. This may in particular be carbon black and / or carbon fibers. It can represent 1 to 10%, relative to the mass of the electrode, more advantageously 3 to 5%.
    As already indicated, the electrodes may comprise a lithium salt. In the present invention, the gelled electrolyte is integrated directly with the electrode materials in the formulation as an electrode binder and electrolyte. Unlike the prior art, it is therefore not necessary to add a liquid electrolyte once the battery assembly.
    The concentration of lithium salt in the electrodes (positive or negative) is advantageously between 0.5 and 5M in the dinitrile compound, more advantageously of the order of 1 M.
    In the positive electrode, the polymer + dinitrile compound advantageously represents 20 to 60% relative to the mass of the positive electrode, more preferably 30 to 40%.
    In the negative electrode, the polymer + dinitrile compound advantageously represents 20 to 60% relative to the mass of the negative electrode, more preferably 30 to 40%.
    The electrodes are advantageously associated with a porous current collector. The current collector of the positive electrode and / or the negative electrode is advantageously a carbon nonwoven. The use of a carbon nonwoven for the two electrodes makes it possible to preserve the flexibility properties of the gelled electrodes. It also makes it possible to avoid the problems of corrosion, generally encountered when the active materials of NMC type electrodes are used in the presence of lithium salt of LiTFSi type and of a conventional aluminum current collector.
    Thus, according to a preferred embodiment, each of the electrodes of the battery according to the invention is associated with a current collector consisting of a carbon nonwoven.
    The battery according to the invention is advantageously a flexible battery. It may also comprise a plurality of gelled electrochemical cores (electrodes + electrolyte).
    According to a particular embodiment, the battery comprises a flexible packaging. The latter is generally made of a multilayer composite material, for example a stack of aluminum layers covered with a polymer of polyethylene, propylene or polyamide type. This flexible package may also include an adhesive layer which may be polyester-polyurethane.
    The present invention also relates to a method for preparing this lithium-ion battery. This process comprises the following steps: a / preparation of a gel electrolyte by: • preparation of a lithium salt solution in a dinitrile compound of formula N = CRC = N, R being a hydrocarbon group CnH2n, n being a number integer between 1 and 2; • forming an electrolyte ink by mixing this solution with a polymer, the mass ratio dinitrile / polymer compound being between 60/40 and 90/10; • formation of a gel electrolyte; b / preparation of a positive electrode gelled by: • preparation of a positive electrode ink containing a positive electrode active material, a polymer and a dinitrile compound of formula N = CRC = N, R being a hydrocarbon group CnH2n , n being an integer between 1 and 2, the weight ratio dinitrile / polymer compound being between 60/40 and 90/10; Forming a gelled positive electrode, advantageously by depositing the positive electrode ink on a current collector; c / preparation of a gelled negative electrode by: • preparation of a negative electrode ink containing a negative electrode active material, a polymer and a dinitrile compound of formula N = CRC = N, R being a hydrocarbon group CnH2n , n being an integer between 1 and 2, the weight ratio dinitrile / polymer compound being between 60/40 and 90/10; Forming a gelled negative electrode, advantageously by depositing the negative electrode ink on a current collector; d / preparing a battery by assembling the positive electrode / electrolyte / negative electrode stack; e / optionally packaging the battery thus formed, preferably in a flexible package. The electrolyte, but also the electrodes can be made by solvent or UV (crosslinking by exposure to ultraviolet radiation).
    In other words, the gelation can be carried out by evaporation of a solvent or by crosslinking the polymer.
    The solvent route consists in diluting the "dinitrile / polymer compound" mixture in a dilution solvent (SD). In this case, the ink (electrolyte and / or electrode) of steps a / c comprises this solvent SD. The gelation is carried out by evaporation of the solvent SD.
    Thus, according to a particular embodiment, the ink of steps a / to c / comprises a solvent SD, the formation of the gel electrolyte and positive and negative electrodes being carried out by evaporation of the solvent SD.
    The solvent SD is advantageously chosen from the group comprising N-methyl-2-pyrrolidone (NMP), methyl ethyl ketone (MEK), dimethylformamide (DMF), tetrahydrofuran (THF) and acetone.
    In step a /, the lithium salt solution in a dinitrile compound may be diluted in the SD solvent prior to mixing with a polymer.
    In the case of the formation of the electrodes (steps a / and b /), the solvent SD may be introduced in the presence of the electrode active material, the polymer and the dinitrile compound.
    Poly (styrene-co-acrylonitrile) and poly (vinylidene fluoride-hexafluoropropylene) polymers (PVdF-HFP) are particularly suitable for the solvent route.
    The formation of the gel electrolyte and the positive and negative electrodes can also be carried out by crosslinking the polymer, by exposure to ultraviolet radiation.
    In step a /, the UV route consists in forming the gel electrolyte by crosslinking the polymer, by exposure to ultraviolet radiation. In this case, the lithium salt solution in a dinitrile compound is not diluted in a solvent (SD) prior to mixing with a polymer.
    In steps b / and c /, the UV route consists of preparing a mixture containing the dinitrile compound, the polymer, the electrode active material, optionally at least one electronic conductor and / or a lithium salt, and then cross-linking the polymer by exposure to ultraviolet radiation.
    Poly (butyl methacrylate-co-isobutyl methacrylate), poly (butyl methacrylate), poly (isobutyl methacrylate), poly (butyl methacrylate-co-methyl methacrylate) and poly (methyl methacrylate) polymers are particularly suitable for the UV route.
    The crosslinking is ensured by the presence of a crosslinking agent. Those skilled in the art will know how to use their technical knowledge to choose the appropriate crosslinking agent.
    The deposition of the electrode inks can be achieved by various conventional deposition techniques, in particular by coating, by printing (screen printing, inkjet ...) or by spraying.
    The formation of the electrolyte may also comprise a deposition step according to one of these techniques. In this case, the mixture containing in particular the polymer and the dinitrile compound is deposited before evaporation of the possible solvent SD or before the crosslinking of the polymer.
    Thus, the battery according to the invention can be produced by successive deposits, advantageously by printing: an electrode ink on a substrate, so as to form a first electrode; an electrolyte ink on the first electrode; of an electrode ink on the electrolyte, so as to form a second electrode of opposite sign to the first electrode.
    The substrate on which the ink forming the first electrode is deposited is advantageously a carbon substrate, more advantageously a carbon nonwoven.
    In general, it is preferable for the dinitrile compound to be soluble in the compounds used (UV or solvent route) in order to obtain a homogeneous mixture of the constituents.
    In the battery according to the invention, the gelling of the electrochemical core (electrolyte + electrodes) has the following advantages: improvement of the manufacturing process due to the absence of the filling step by a liquid electrolyte; improved safety, the dinitrile compound used being non-flammable and non-toxic; obtaining a flexible battery, or even deformable; possibility of new solid battery configurations, for example in three-dimensional form, in the form of wires or cables; possibility of inserting these new battery configurations into a textile for example; improvement of electrochemical stability; Increasing the operating temperature range: from -20 ° C to 250 ° C. possibility of printing the battery on a polymer substrate. The invention and the advantages thereof will appear more clearly from the following figures and examples given to illustrate the invention and not in a limiting manner.
    DESCRIPTION OF THE FIGURES
    Figure 1 illustrates the ionic conductivity between -10 ° C and 60 ° C of liquid electrolytes. Figure 2 illustrates the ionic conductivity of gel electrolytes according to the invention.
    FIG. 3 illustrates the cyclic voltammetric diagram of a gel electrolyte according to the invention.
    FIG. 4 illustrates the cyclic voltammetric diagram of a gel electrolyte according to the invention.
    FIG. 5 illustrates the specific capacity of a positive electrode at different charging and discharging regimes, in a half-battery comprising a gel system according to the invention.
    FIG. 6 illustrates the specific capacity of a positive electrode at different charging and discharging regimes, in a half-battery comprising a gel system according to the invention.
    FIG. 7 illustrates the voltage as a function of the specific capacity of gel systems according to the invention.
    FIG. 8 illustrates the specific capacity of a battery comprising a gel system according to the invention, at different charging and discharging regimes.
    FIG. 9 illustrates the specific capacity of a battery comprising a gel system according to the invention.
    EXAMPLES OF CARRYING OUT THE INVENTION
    Several examples of gelled electrochemical systems according to the invention have been prepared and used in half-cell or stack configuration. a) Preparation of the Gel Electrolyte According to the Invention
    Lithium salts LiTFSi (lithium bis-trifluoromethanesulfonimide) and LiBOB (lithium bis (oxatlato) borate) are heat-solubilized in a dinitrile compound (succinonitrile or malononitrile which are solid at room temperature) at 0.8M for LiTFSi and 0.2M for the LiBOB.
    FIG. 1 represents the measurements of ionic conductivity carried out on these solutions between -10 and 60 ° C., and compared with a conventional liquid electrolyte compatible with use in a lithium-ion system (LPx: EC / PC / DMC type electrolyte) IM LiPF6, EC = ethylene carbonate, PC = propylene carbonate, DMC = dimethyl carbonate).
    These solutions of lithium salts in a dinitrile compound are then mixed with the polymers which will serve as gelling matrix (Table 1).
    The mixture is made in a solvent route (addition of the salt solution diluted in a solvent at 40% solids) or in a UV route (addition of the salt solution at 0.8 or 0.2M).
    The solvent route makes it possible to obtain a gel electrolyte after evaporation of the solvent (generally N-methyl-2-pyrrolidone NMP, methyl ethyl ketone MEK, dimethylformamide DMF, tetrahydrofuran THF or acetone).
    The UV route makes it possible to obtain a gel electrolyte by crosslinking the polymer by exposure to ultraviolet radiation.
    In all the examples, the mass ratio dinitrile / polymer compound is equal to 70/30.
    Prior to the formation of the gel electrolyte (by evaporation of the solvent or by UV crosslinking), the various mixtures are coated on a polymer substrate (polyethylene terephthalate, PET) or glass in order to obtain gel electrolytes. 40 to 90pm thick.
    In general, the preparation of gel electrolytes according to the invention can be carried out under anhydrous or non-anhydrous conditions, without affecting the properties of the gel electrolyte. However, the gel electrolytes intended to be integrated in lithium metal system are made under anhydrous conditions so as to avoid any presence of water.
    TABLE 1 Composition, conditions of production and properties of gel electrolytes according to the invention PStyA: poly (styrene-co-acrylonitrile)
    Polymer A: Poly (Butylmethacrylate-Co-Isobutylmethacrylate)
    Polymer B: poly (butyl methacrylate)
    Polymer C: Poly (isobutyl methacrylate)
    Polymer D: poly (butylmethacrylate-co-methylmethacrylate)
    PMMA polymer: poly (methyl methacrylate)
    PVdF-HFP polymer: poly (vinylidene fluoride-hexafluoropropylene); reference 21216 from Solvay
    Route S: solvent route, formation of the electrolyte by evaporation of the solvent
    UV channel: formation of the electrolyte by polymer crosslinking by exposure to ultraviolet radiation
    Elongation and homogeneity: the classification was done visually, the note 4 indicating the best mechanical properties.
    The INV-1 to INV-7 gel electrolytes were characterized in terms of ionic conductivity (FIG. 2).
    The INV-6 and INV-7 gel electrolytes have the best conductivity and the most optimized mechanical properties. These two gel electrolytes are stable up to 5V against lithium, and are therefore usable in lithium metal and lithium-ion configuration for all the conventionally used electroactive materials (FIGS. 3 and 4). b) Preparation of half-cells and batteries comprising a gel system according to the invention
    Preparation of gel electrolytes:
    The half-cells and batteries comprising the gel system according to the invention were prepared from the electrolytes (Table 2) and the electrodes (Table 3) described below.
    Table 2: Composition and conditions for obtaining gel electrolytes according to the invention.
    The following formulation (ink) was used: PVdF-HFP: 15% by weight; succinonitrile: 35% by weight;
    LiTFSi: 0.8M in succinonitrile;
    LiBOB: 0.2M in succinonitrile; acetone: amount adjusted to obtain a solids content (by mass) of 46%.
    For INV-8 and INV-9, the succinonitrile / polymer / lithium salt / acetone mixture is coated on a PET-type polymer substrate and then dried at 60 ° C for 2 hours to remove the formulation solvent (acetone) .
    The deposit once dried forms a gel that can be handled and removed from its substrate. It is then cut to a diameter of 16 mm thanks to a cookie cutter to be assembled in button-type format.
    Preparation of gel electrodes according to the invention
    In order to achieve a fully gelled system, gelled electrodes were prepared by incorporating a dinitrile compound and a polymer (Table 3).
    Table 3: Composition of gel electrodes according to the invention.
    For positive electrodes, the following formulation (ink) was used:
    LiFePCL or LiNiMnCoCL: 48% by weight; carbon black (Super P from Timcal): 1% by weight; carbon fiber (VGCF-H from Showa Denko): 1% by weight; PVdF-HFP: 15% by weight; succinonitrile: 35% by weight;
    LiTFSi: 0.8M in succinonitrile;
    LiBOB: 0.2M in succinonitrile; DMF: amount adjusted to obtain a solids content (by mass) of 40%. For the negative electrode, the following formulation (ink) was used:
    Li4Ti50 i2: 48% by weight; carbon black (Super P from Timcal): 1% by weight; carbon fiber (VGCF-H from Showa Denko): 1% by weight; PVdF-HFP: 15% by weight; succinonitrile: 35% by weight;
    LiTFSi: 0.8M in succinonitrile;
    LiBOB: 0.2M in succinonitrile; DMF: amount adjusted to obtain a solids content (by mass) of 40%. Preparation of the gelled battery systems of the invention
    These two formulations (positive and negative electrode inks) are then coated and then dried at 60 ° C. for 24 hours on a carbon nonwoven carbon substrate. The use of a non-woven carbon promotes adhesion and eliminate the corrosion problems generally encountered when the NMC material and LiTFSi salt are deposited on aluminum.
    The composition of the ink obtained may vary depending on the material used and the intended application. Thus, by varying the amount of active material and the coating thickness of the inks formulated on the current collector, it is possible to control the weight of the electrode, ie the mass of active material per unit of surface. In general, this basis weight is directly related in surface capacity with respect to the specific capacity (mA.h.cm'2) of the material considered.
    Once the electrode ink has been coated or printed and dried on the carbon nonwoven collector, pellets are cut to a diameter of 14 millimeters by a punch and then weighed. Weighing makes it possible to know the mass of active material contained in the pellet. It is then possible to know the capacity (mA.h) of the pellet.
    The mass of active material in the pellet is determined by the following relation:
    in which tcîma, mtot and mconecteur represent respectively the mass of active material, the total mass of the pellet and the mass of the current collector. These masses are all in milligrams (mg). The notation% {MA) represents the percentage of active material in the formulation of the electrode.
    The capacity of the tablet (Cpastiiie) in mA.h can then be calculated:
    Cma representing the specific capacity of the active material in mA.h.g'1.
    The specific capabilities used for capacity calculations are reported in Table 4.
    Table 4: Specific capacities for the main electrode materials used.
    Once the pellets are characterized (mass, thickness and capacity), they are dried under vacuum at 80 ° C for 48 hours before being used to mount button cells in an inert medium. Unlike conventional systems, no step of adding a liquid electrolyte or vacuum impregnation phase is required.
    In general, the electrodes are not calendered, unlike conventional electrodes. Indeed, the calendering can generate the exudation of the electrolyte out of the polymer matrix. In addition, the use of a carbon substrate makes this step superfluous. c) Stack tests
    Once the electrodes and the gel electrolyte according to the invention are assembled in the button cell format, they are characterized on a cycling bench to evaluate their electrochemical performance.
    Two types of configuration were evaluated: half-cell configuration: a positive electrode material (LFP or NMC) against lithium metal (FIGS. 5-7); Full system configuration: a positive electrode (NMC) facing a negative electrode (LTO) (Figures 8 and 9).
    Half-stack configuration: NMC us. lithium metal (Figures 5 and 7)
    As shown in FIG. 5, the specific capacities restored are similar to the theoretical specific capacity of the NMC material (170 mA.h.g'1).
    In addition, and surprisingly, the gel system according to the invention makes it possible to restore 100 mA.h.g'1 at high speed (C / D), which corresponds to a complete charge and discharge in 1 hour.
    The observed results are very stable, there is no loss of capacity during the cycles.
    Half-stack configuration: LFP us. lithium metal (Figures 6 and 7)
    As shown in FIG. 6, the specific capacitances restored by the LFP / Li metal system are similar to the theoretical specific capacitance of the LFP material (160 mA.h.g'1).
    On the other hand, the LFP material being a less good electronic conductor than the NMC material, the capacity restored falls rather quickly for revolutions higher than C / 10-D / 10.
    As shown in Figure 7, the two systems NMC / Li and LFP / Li have charging and discharge rates comparable to the best formulations in the literature with very low polarizations.
    Full system configuration: NMC us. LTO (Figures 8 and 9)
    Figures 8 and 9 show that the Gelled NMC / LTO system is functional and very stable during cycles. In addition, the restored capacities are slightly lower than the theoretical specific capacities (150 instead of 160 mA.h.g'1).
    权利要求:
    Claims (10)
    [1" id="c-fr-0001]
    A lithium ion battery comprising: a positive electrode comprising a positive electrode active material, and preferably a lithium salt; an electrolyte comprising a lithium salt; a negative electrode comprising a negative electrode active material, and preferably a lithium salt; characterized in that the positive electrode, the negative electrode and the electrolyte are all in the form of gels, and all three comprise a polymer and a dinitrile compound of the formula N = C-R-C = N; R being a CnH2n hydrocarbon group, n being an integer between 1 and 2; the dinitrile / polymer compound weight ratio being between 60/40 and 90/10.
    [2" id="c-fr-0002]
    2. lithium-ion battery according to claim 1, characterized in that the dinitrile compound is succinonitrile or malononitrile.
    [3" id="c-fr-0003]
    3. lithium-ion battery according to claim 1 or 2, characterized in that the mass ratio of dinitrile / polymer compound is between 65/35 and 75/25.
    [4" id="c-fr-0004]
    4. lithium-ion battery according to one of claims 1 to 3, characterized in that the polymer is selected from the group comprising: poly (styrene-co-acrylonitrile); poly (butyl methacrylate-co-isobutyl methacrylate); poly (butyl methacrylate); poly (isobutyl methacrylate); poly (butyl methacrylate-co-methyl methacrylate); poly (methyl methacrylate); poly (vinylidene fluoride-hexafluoropropylene); polyethylene oxide; and polyvinylpyrrolidone.
    [5" id="c-fr-0005]
    5. lithium-ion battery according to one of claims 1 to 4, characterized in that the lithium salt is selected from the group comprising: lithium bis-trifluoromethanesulfonimide; lithium bis (oxatlato) borate); LiPF6; L1CIO4; LiBF4; LiAsFg; L1CF3SO3; LiN (CF3SO2) 3; LiN (C2F5SO2); and their mixtures.
    [6" id="c-fr-0006]
    6. lithium-ion battery according to one of claims 1 to 5, characterized in that, in the electrolyte, the lithium salt has a concentration of between 0.5 and 5M in the dinitrile compound.
    [7" id="c-fr-0007]
    7. A method for preparing a lithium-ion battery according to one of claims 1 to 6, comprising the following steps: a / preparation of a gel electrolyte by: • preparation of a lithium salt solution in a compound dinitrile of formula N = CRC = N, R being a hydrocarbon group CnH2n, n being an integer between 1 and 2; • forming an electrolyte ink by mixing this solution with a polymer, the mass ratio dinitrile / polymer compound being between 60/40 and 90/10; • formation of a gel electrolyte; b / preparation of a positive electrode gelled by: • preparation of a positive electrode ink containing a positive electrode active material, a polymer and a dinitrile compound of formula N = CRC = N, R being a hydrocarbon group CnH2n , n being an integer between 1 and 2, the weight ratio dinitrile / polymer compound being between 60/40 and 90/10; Forming a gelled positive electrode, advantageously by depositing the positive electrode ink on a current collector; c / preparation of a gelled negative electrode by: • preparation of a negative electrode ink containing a negative electrode active material, a polymer and a dinitrile compound of formula N = CRC = N, R being a hydrocarbon group CnH2n , n being an integer between 1 and 2, the weight ratio dinitrile / polymer compound being between 60/40 and 90/10; Forming a gelled negative electrode, advantageously by depositing the negative electrode ink on a current collector; d / preparing a battery by assembling a positive electrode / electrolyte / negative electrode stack.
    [8" id="c-fr-0008]
    8. A process for preparing a lithium-ion battery according to claim 7, characterized in that the ink of steps a / c comprises a solvent (SD), and in that the formation of the gel electrolyte and positive and negative electrodes is made by evaporation of the SD solvent.
    [9" id="c-fr-0009]
    9. A method for preparing a lithium-ion battery according to claim 8, characterized in that the solvent SD is selected from the group comprising N-methyl-2-pyrrolidone, methyl ethyl ketone, dimethylformamide, tetrahydrofuran and acetone.
    [10" id="c-fr-0010]
    10. A method of preparing a lithium-ion battery according to claim 7, characterized in that the formation of the gel electrolyte and the positive and negative electrodes is carried out by crosslinking the polymer, by exposure to ultraviolet radiation.
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    同族专利:
    公开号 | 公开日
    EP3341987A1|2018-07-04|
    EP3341987B1|2019-04-10|
    US10566658B2|2020-02-18|
    JP6999425B2|2022-01-18|
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    JP2018525774A|2018-09-06|
    US20180123169A1|2018-05-03|
    WO2017032940A1|2017-03-02|
    引用文献:
    公开号 | 申请日 | 公开日 | 申请人 | 专利标题
    US20110311864A1|2010-06-18|2011-12-22|Sony Corporation|Nonaqueous electrolyte and nonaqueous electrolyte battery|
    US20130177799A1|2011-12-26|2013-07-11|Sony Corporation|Electrolytic solution, secondary battery, battery pack, electric vehicle, electric power storage system, electric power tool, and electronic apparatus|
    EP2833462A1|2012-03-28|2015-02-04|Ocean's King Lighting Science&Technology Co., Ltd.|Solid electrolyte battery|FR3073672A1|2017-11-14|2019-05-17|Commissariat A L'energie Atomique Et Aux Energies Alternatives|PROCESS FOR PREPARING AN ELECTROCHEMICAL CELL FOR LITHIUM BATTERY COMPRISING A SPECIFIC GELIFIED ELECTROLYTE|
    EP3457486A4|2017-06-20|2019-08-28|LG Chem, Ltd.|Multilayer polymer solid electrolyte and all-solid-state battery comprising same|
    US10680233B2|2016-11-15|2020-06-09|Commissariat A L'energie Atomique Et Aux Energies Alternatives|Method for manufacturing an electrode for an accumulator|CA2435218A1|2003-07-28|2005-01-28|Michel Armand|Plastic crystal electrolytes based on a polar, neutral matrix|
    CA2616327C|2005-07-29|2014-05-13|National Research Council Canada|Plastic crystal electrolyte in lithium-based electrochemical devices|
    KR101508788B1|2006-06-02|2015-04-06|미쓰비시 가가꾸 가부시키가이샤|Nonaqueous electrolyte solution and nonaqueous electrolyte battery|
    US8895193B2|2007-05-11|2014-11-25|National Research Council Of Canada|Plastic crystal electrolyte with a broad potential window|
    CN102948000B|2010-06-14|2016-05-18|株式会社Lg化学|Electrolyte used for electrochemical equipment, prepare described electrolytical method and comprise described electrolyte electrochemical device|
    FR2963482B1|2010-07-29|2013-01-25|Commissariat Energie Atomique|ELECTRODE FOR LITHIUM ACCUMULATOR|
    KR101351897B1|2011-01-20|2014-01-17|주식회사 엘지화학|Electrolyte for electrochemical device, the preparation method thereof and electrochemical device comprising the same|
    FR2979630B1|2011-09-05|2013-10-04|Univ Provence Aix Marseille 1|BLOCK COPOLYMERS HAVING A POLYANIONIC BASED ON ANION MONOMER TYPE TFSILI AS ELECTROLYTE BATTERY.|
    KR20140083023A|2011-10-20|2014-07-03|더 유니버시티 오브 아크론|Stretchable, solvent free, completely amorphous solid electrolyte films|
    KR101606898B1|2014-04-03|2016-03-28|숭실대학교산학협력단|Flexible secondary lithium battery|
    KR101648465B1|2015-02-17|2016-08-16|주식회사 제낙스|Gel polymer electrolyte, method for manufacturing the same, and electrochemical device including the same|
    FR3035544B1|2015-04-21|2017-04-14|Rhodia Operations|SOLID POLYMER ELECTROLYTE AND ELECTROCHEMICAL DEVICES COMPRISING SAME|
    KR102314039B1|2016-07-28|2021-10-18|삼성에스디아이 주식회사|Electrolyte for lithium metal battery and lithium metal battery comprising the same|
    FR3058834B1|2016-11-15|2019-05-10|Commissariat A L'energie Atomique Et Aux Energies Alternatives|METHOD FOR MANUFACTURING ELECTRODE FOR ACCUMULATOR|
    FR3058833B1|2016-11-15|2019-05-10|Commissariat A L'energie Atomique Et Aux Energies Alternatives|PROCESS FOR MANUFACTURING A SEPARATORY MEMBRANE FOR ACCUMULATOR|
    US20190103627A1|2017-10-04|2019-04-04|Wildcat Discovery Technologies, Inc.|Solid electrolyte compositions|CN108767312B|2018-04-19|2021-08-27|中国科学院青岛生物能源与过程研究所|Polyamide-based solid electrolyte and preparation method thereof|
    FR3086806B1|2018-09-28|2020-10-23|Commissariat Energie Atomique|PROCESS FOR PREPARING A GELIFIED ELECTROLYTE|
    WO2020075514A1|2018-10-12|2020-04-16|株式会社村田製作所|Thread battery|
    KR102180203B1|2019-01-17|2020-11-18|서울대학교산학협력단|Anode material of Lithium ion battery and method of preparing the same|
    EP3928367A1|2019-02-21|2021-12-29|Commissariat à l'Energie Atomique et aux Energies Alternatives|Nitrile solvent-based electrolyte for organic battery|
    KR20210135861A|2020-05-06|2021-11-16|주식회사 엘지에너지솔루션|Manufacturing method for secondary battery having improved resistance|
    FR3112654A1|2020-07-15|2022-01-21|Pellenc Energy|Method and equipment for manufacturing a battery cell|
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    优先权:
    申请号 | 申请日 | 专利标题
    FR1557896A|FR3040550B1|2015-08-25|2015-08-25|GELIFIED LITHIUM ION BATTERY|FR1557896A| FR3040550B1|2015-08-25|2015-08-25|GELIFIED LITHIUM ION BATTERY|
    PCT/FR2016/052064| WO2017032940A1|2015-08-25|2016-08-11|Lithium-ion gel battery|
    EP16763907.9A| EP3341987B1|2015-08-25|2016-08-11|Lithium-ion gel battery|
    JP2017565980A| JP6999425B2|2015-08-25|2016-08-11|Lithium ion gel battery|
    US15/831,709| US10566658B2|2015-08-25|2017-12-05|Lithium-ion gel battery|
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