POSITIVE ELECTRODE COMPOSITION COMPRISING A MIXTURE OF ACTIVE MATERIALS OF THE LITHIUM MANGANESE AND IRON PHOSPHATE TYPE

Abstract

POSITIVE ELECTRODE COMPOSITION COMPRISING A MIXTURE OF MANGANESE AND IRON LITHIUM PHOSPHATE ACTIVE INGREDIENTS. The present invention relates to a composition of electrochemically active materials comprising at least two manganese and iron lithium phosphate (LMFP) type active materials, each corresponding to the following formula (LMFP1) or (LMFP2) having distinct iron relative to manganese contents, as well as electrodes comprising a formulation based on this composition, and the electrochemical elements containing them. Figure for abstract: None

Description

Title of the invention: Composition of positive electrodes comprising a mixture of materials ACTIVE INGREDIENTS OF THE MANGANESE LITHIUM PHOSPHATE TYPE AND IRON

[0001] The present invention relates to the field of energy storage and lithium batteries in particular. More specifically, the present application relates to active material compositions for positive electrodes, and to ink formulations containing them that are coated onto current collectors to manufacture these cathodes.

[0002] The invention is particularly useful in the field of rechargeable lithium-ion (Li-ion) type electrochemical elements.

[0003] The electrodes, in particular the positive ones, consist of a metal current collector on which is coated a composition of active material, conductive element(s), binder(s) and possible additive(s).

[0004] The electrodes are prepared from an ink comprising the composition, generally formulated in an organic solvent medium, coated onto a current collector, the solvent of which is evaporated, before calendering so as to adjust the thickness of the ink layer on the collector.

[0005] Lithified manganese and iron phosphates of formula

[0006] LixMnly.zFeyMzPO4 (LMFP)

[0007] with 0.8 <x<l,2 ; l-y-z> 0.5; 0.05 <y<0,5 et 0<z<0,2 sont également connus pour leur utilisation comme matière active cathodique d’éléments lithium-ion. Ces phosphates contiennent du manganèse, du fer et un ou plusieurs éléments substituants symbolisés par le symbole M.

[0008] These compounds are known to offer superior safety in use because the lithium phosphates of transition metals are stable at high temperature.

[0009] The presence of iron is linked to the very low diffusion coefficient of lithium in the lithium manganese phosphate compound, which makes its use for electrochemical storage unsuitable. However, the presence of iron in lithium manganese and iron phosphates poses a problem during charging: during lithium deintercalation, the LMFP material transitions from a solid solution (olivine-type) to a two-phase system (olivine / heterosite-type). This phase change is accompanied by the transition from a charge plateau characteristic of iron to a second plateau characteristic of manganese.

[0010] This transition from one plateau to another is accompanied by a limited electrochemical charge reaction kinetics and is illustrated by a peak in the charge transfer resistance during charging.

[0011] It is therefore necessary to minimize this kinetic limitation linked to this transition, inherent in LMFP type materials.

[0012] WO2022 / 47705 describes an electrode composition comprising, as materials Two phosphate-type materials with the same formula but low manganese content are used. To improve electrode compression, one material is in single-crystal form, the other is in secondary particle form.

[0013] It therefore remains to propose compositions based on LMFP-type active materials free from transition problems.

[0014] One of the aims of the invention is therefore to propose a composition of active materials of the LMFP type allowing to limit the effects related to this transition.

[0015] To this end, the invention relates to a composition of electrochemically active materials comprising at least two active materials of the type lithium manganese and iron phosphate (LMFP), each corresponding to the following formula (LMFP1) or (LMFP2), respectively:

[0016] LixMni yi_ziFeyiMlziPO4 LixMniy2.z2Fey2M2z2PO4

[0017] (LMFP1) (LMFP2)

[0018] in which

[0019] M1 and M2, identical or different, are chosen from the group consisting of B, Mg, Al, Si, Ca, Ti, V, Cr, Co, Ni, Cu, Zn, Y, Zr, Nb and Mo,

[0020] Each of the x's is identical or different and such that 0.8 < x < 1.2;

[0021] O^l-yrZ^l; 0,5 <l-y2-z2<l;

[0022] 0.05<y! <0.5; 0.05< y2 <0.5

[0023] 0 < Zi < 0.2; and 0 < z2 < 0.2;

[0024] Characterized in that the ratios of iron to manganese of LMFP1 and LMFP2 are distinct and such that yi>y2 and l-y2-z2>l-yi-zi.

[0025] Thus, the invention proposes a composition comprising several LMFP-type active materials, having distinct iron content relative to manganese, allowing to minimize the impact of the transition of the charge plateaus, to smooth the peak of charge transfer resistance and therefore to improve the charge.

[0026] The invention also relates to an electrode comprising a current collector made of a metal strip which is covered on at least one of its faces by an electrode formulation comprising a composition according to the invention.

[0027] The invention further relates to an electrochemical element comprising at least one electrode according to the invention as a positive electrode.

[0028] According to other advantageous aspects of the invention, the composition comprises one or more of the following features, taken individually or in all technically possible combinations:

[0029] LMFP type compounds correspond to distinct general formulas, in that they contain different respective levels of iron and / or manganese.

[0030] According to one embodiment, (yi / (l-yi-Zi)) is distinct from (y2 / (l-y2-z2)).

[0031] According to a particular mode, the material corresponding to formula (LMFP1) has a higher iron content than the iron content of the material corresponding to formula (LMFP2).

[0032] According to a particular mode, the material corresponding to formula (LMFP1) has a lower manganese content than the manganese content of the material corresponding to formula (LMFP2).

[0033] According to a particular mode, (yi / (l-yi-Zi))> (y2 / (l-y2-z2)).

[0034] According to one embodiment, in formulas (LMFP1) and (LMFP2), x = 1.

[0035] According to one embodiment, said composition comprises:

[0036] of 30 to 95% of compound (LMFP2), in particular of 40 to 85%, particularly of 60 to 80%, more specifically from 65 to 75%; and

[0037] of 5 to 70% of compound (LMFP1), in particular from 10 to 60%, particularly from 20 to 40%; more particularly from 25 to 35%;

[0038] the percentages being in weight relative to the total weight of (LMFP1) and (LMFP2).

[0039] According to one embodiment, said composition comprises:

[0040] of 60 to 80% of compound (LMFP2), particularly 65 to 75%; and

[0041] of 20 to 40% of compound (LMFP1), particularly of 25 to 35%;

[0042] the percentages being in weights relative to the total weight of (LMFP1) and (LMFP2).

[0043] According to one embodiment, said composition comprises:

[0044] of 65 to 75% of compound (LMFP2); and

[0045] of 25 to 35% of compound (LMFP1);

[0046] the percentages being in weights relative to the total weight of (LMFP1) and (LMFP2).

[0047] According to an advantageous embodiment, in formulas (LMFP1) and (LMFP2), yi and y2 are such that 0.05<(yi - y2)<0.5, preferably 0.1 <(yi - y2)<0.45.

[0048] According to one embodiment, the compounds (LMFP1) and (LMFP2) are in the form of secondary particles.

[0049] The term “secondary particle” refers to an aggregate resulting from the agglomeration of several primary particles, a primary particle consisting of a nanoparticle, typically a single crystal.

[0050] Nanoparticles typically have a diameter of less than 1000 nm, in particular less than 100 nm.

[0051] According to the invention, the secondary particles of (LMFP1) and (LMFP2) have a size Identical or different. Advantageously, (LMFP1) and (LMFP2) have distinct particle sizes. Without being bound by any theory, a different particle size improves electrode compression and thus reduces its porosity, ultimately increasing its electrochemical properties.

[0052] The secondary particles constituting (LMFP1) or (LMFP2), respectively, have a size distribution characterized by a first median volume diameter of the particles Dv50a > 300 nm; and

[0053] the secondary particles constituting (LMFP2) or (LMFP1), respectively, have a size distribution characterized by a second median diameter in volume of the particles Dv50b < lOpm.

[0054] According to one embodiment, the first median diameter and the second median diameter are identical: Dv50b / Dv50a = 1.

[0055] According to another embodiment, the first median diameter and the second median diameter are different; typically Dv50b / Dv50a > 5.

[0056] According to one embodiment, the volume of secondary particles having median diameter Dv50a represents from 10 to 40%, preferably between 15 and 25%, in particular about 20% of the total volume of secondary particles constituting (LMFP1) and (LMFP2).

[0057] It is understood that the composition according to the invention may further comprise one or more ingredients.

[0058] Thus, it may include one or more other LMFP-type compounds as active ingredients.

[0059] It may also include one or more other distinct active materials of LMFP type compounds.

[0060] Thus, according to one embodiment, said composition may comprise one or more additional active substances, chosen from the following active substances: - LVPF type active substances conforming to formula (I)

[0061] Lii+xVi yMyPO4Fzavec 0 <x<0.15, 0<y<0.5, 0.8<z<1.2, et M est choisi parmi le groupe consistant en Ti, Al, Mg, Mn, Fe, Co, Y, Cr, Cu, Ni et Zr; - Active materials of the lamellar oxide type corresponding to formula (II):

[0062] LixMi y_z_wM'yM”zM”'wO2 (LMO2) where M, M', M” and M'” are selected from the group consisting of B, Mg, Al, Si, Ca, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Y, Zr, Nb, W and Mo provided that at least M or M' or M” or M'” is selected from Mn, Co, Ni, or Fe; M, M', M” and M'” being different from each other; and 0 <x<l,4 ; 0<y<0,5 ; 0<z<0,5 ; 0<w<0,2 et x+y+z+w<2,l ; plus particulièrement 0,8< x<l,4 ; - Active substances of the type lithium phosphate of manganese and iron distinct from (LMFP1) and (LMFP2) and corresponding to formula (III):

[0063] LixMni y zFeyMzPO4 where 0.8 <x<l,2 ; 0,5<l-y-z<l ; 0<y<0,5 ; 0<z<0,2 ; M étant un ou several elements chosen from the group consisting of Al, B, Mg, Si, Ca, Ti, V, Cr, Co, Cu, Ni, Zn, Y, Zr, Nb, W and Mo; - Spinel-type active substances corresponding to formula (IV):

[0064] LixMn2_y_zM'yM"zO4, where M' and M" are chosen from the group consisting of B, Mg, Al, Si, Ca, Ti, V, Cr, Fe, Co, Ni, Cu, Zn, Y, Zr, Nb and Mo; M' and M" being different from each other, and 1 <x<1,4 ; 0<y<0,6 ; 0<z<0,2.

[0065] In particular, lamellar oxide-type active ingredients may be selected from among nickel lithia oxides. Thus, according to one embodiment, said composition may comprise, as additional active ingredient(s), one or more nickel lithia oxides selected from:

[0066] i) a lithium oxide of nickel, manganese and cobalt (NMC) of formula Liw(NixMn yCozMt)O2 where 0.9 <w<l,l ; 0<x ; 0<y ; 0<z ; 0<t ; M étant au moins un élément choisi dans le groupe constitué de Al, B, Mg, Si, Ca, Ti, V, Cr, Fe, Cu, Zn, Y, Zr, Nb, W, Mo, Sr, Ce, Ta, Ga, Nd, Pr et La, et plus particulièrement 0,8< x,

[0067] ii) a lithium nickel, cobalt and aluminium (NCA) oxide of formula Liw(NixCoy AlzMt)O2 where 0.9 <w<l,l ; 0<x ; 0<y ; 0<z ; 0<t ; M étant au moins un élément choisi dans le groupe constitué de B, Mg, Si, Ca, Ti, V, Cr, Mn, Fe, Cu, Zn, Y, Zr, Nb, W, Mo, Sr, Ce, Ga, Ta, Nd, Pr et La ; plus particulièrement 0,83< x et

[0068] iii) a lithium nickel, manganese, cobalt and aluminium oxide (NMCA) of formula Liw(NixCoyAlzMnt)O2 where 0.9 <w<l,l ; 0<x ; 0<y ; 0<z ; 0<t, plus particulièrement 0,83< x.

[0069] The present invention also relates to an electrode comprising the composition according to the invention. Said composition can indeed be included in the composition of an electrode formulation coated on a current collector.

[0070] Typically, said formulation is in the form of a monolayer.

[0071] The term "electrode formulation" refers to the layer covering the current collector on at least one of its faces, comprising the active material composition according to the invention. Thus, typically, said formulation comprises, in addition to the electrochemically active materials, one or more electronically conductive material(s), binder(s), and / or optional additive(s), among other things.

[0072] According to one embodiment, the current collector consists of a solid or perforated metal strip, which is covered on at least one of its faces by an electrode formulation, said formulation comprising a composition according to the invention.

[0073] Said metal strip may be made of aluminum or an alloy comprising mainly aluminum. Advantageously, the metal strip is made of aluminum. Said strip may be coated on at least one of its faces with an anti-corrosion coating, improving electronic conductivity and / or improving the adhesion of the active material layer to the strip.

[0074] An anti-corrosion coating is understood to mean a layer of material that limits or prevents the attack of the strip by moisture, and / or a pH that is too acidic or basic and likely to affect the surface condition, integrity or performance of the strip.

[0075] According to one embodiment, said strip is an aluminium strip coated with a carbon (Al / C) coating, said coating being able to consist of amorphous carbon, graphite, carbon fibres, carbon nanotubes and mixtures thereof.

[0076] Typically, the formulation is coated on the face or faces of the strip possibly covered with said coating.

[0077] The coated current collector can therefore be coated on one or each of its faces with said formulation.

[0078] The term “binder” means a compound that strengthens the cohesion between the particles of active materials and improves the viscosity and / or adhesion of the formulation to the current collector.

[0079] Said formulation may further comprise one or more electronically conductive materials, which may typically be selected from graphite, carbon black, acetylene black, soot, graphene, carbon nanotubes or a mixture thereof.

[0080] Said formulation can be prepared from an ink constituted by mixing its ingredients with a solvent.

[0081] According to another object, the present invention also relates to a method for preparing an electrode according to the invention, said method comprising:

[0082] - The preparation of an ink comprising the addition of the ingredients of the formulation electrode to a solvent;

[0083] - the application of said ink to the coating of said metal strip;

[0084] - drying; and

[0085] - calendering.

[0086] Generally, an electrode can be manufactured by preparing an ink comprising the composition of active materials, or the active materials, as appropriate, mixed with one or more binders, one or more electronically conductive materials, and a solvent.

[0087] This ink can then be coated on at least one of the faces of a current collector possibly coated with a coating as described above.

[0088] The ink can then be dried, for example in a drying oven or a furnace.

[0089] The thickness of the resulting coated formulation can then be adjusted in a calendering step, by passing the electrode between two rollers exerting pressure on the surface of the electrode.

[0090] According to another object, the invention also relates to an electrochemical element of type lithium-ion comprising at least one electrode as defined above.

[0091] According to one embodiment, said electrode is a positive electrode (cathode) within said element.

[0092] The lithium-ion element can be manufactured conventionally. At least one cathode, at least one separator, and at least one negative electrode (anode) are stacked. The assembly can be wound to form a cylindrical electrochemical bundle. The invention is not limited to the manufacture of cylindrical elements. The element can also be prismatic or pouch-type. The electrodes can also be stacked to form a planar electrochemical bundle. A connecting piece is attached to an edge of the cathode not covered with active material. It is connected to a current output terminal. The anode can be electrically connected to the element container. Conversely, the cathode can be connected to the element container and the anode to a current output terminal. After being inserted into the element container, the electrochemical bundle is impregnated with electrolyte. The element is then hermetically sealed.The element can also be conventionally equipped with a safety valve that causes the element's container to open if the element's internal pressure exceeds a predetermined value.

[0093] The electrolyte may be liquid and comprise a lithium salt dissolved in an organic solvent. This lithium salt can be chosen from lithium perchlorate LiClO4, lithium hexafluorophosphate LiPF6, lithium tetrafluoroborate LiBF4, lithium hexafluoroarsenate LiAsF6, lithium hexafluoroantimonate LiSbF6, lithium trifluoromethanesulfonate LiCF3SO3, lithium bis(fluorosulfonyl)imide Li(FSO2)2N (LiFSI), lithium trifluoromethanesulfonimide LiN(CF3SO2)2 (LiTFSI), lithium trifluoromethanesulfonemethide LiC(CF3SO2)3 (LiTFSM), lithium bisperfluoroethylsulfonimide LiN(C2F5SO2)2 (LiBETI), lithium 4,5-dicyano-2-(trifluoromethyl)imidazolide (LiTDI), lithium bis(oxalatoborate) (LiBOB), the lithium difluoro(oxalato)borate (LIDFOB), lithium tris(pentafluoroethyl)trifluorophosphate LiPF3(CF2CF3)3 (LiFAP), lithium difluorophosphate LiPO2F2 and mixtures thereof.

[0094] The electrolyte solvent can be chosen from saturated cyclic carbonates, unsaturated cyclic carbonates, linear carbonates, alkyl esters, ethers, cyclic esters, such as lactones.

[0095] Alternatively, the electrolyte may be a solid. It may be a lithium-ion-conducting compound, chosen, for example, from lithium-ion-conducting oxides and lithium-ion-conducting sulfides. The electrolyte may also be a lithium-ion-conducting polymer, such as polyethylene oxide (PEO), polyphenylene sulfide (PPS), and polycarbonate.

[0096] The electrolyte can also be in the form of a gel obtained by impregnating a polymer with a liquid mixture comprising at least one lithium salt and an organic solvent.

[0097] The separator may consist of a layer of polypropylene (PP), polyethylene (PE), polytetrafluoroethylene (PTFE), polyacrylonitrile (PAN), polyester such as polyethylene terephthalate (PET), poly(butylene) terephthalate (PBT), cellulose, polyimide, glass fibers, or a mixture of layers of different types. The aforementioned polymers may be coated with a ceramic layer and / or polyvinylidene difluoride (PVdF) or poly(vinylidene-hexafluoropropylene fluoride (PVdF-HFP) or acrylates.

[0098] The invention will become clearer upon reading the following description, given solely by way of non-limiting example, and made with reference to the drawings in which: FIGURES

[0099] [Fig. 1] The [Fig. 1] represents the variation of the voltage as a function of the capacitance for the compounds of examples 1 and 2 and highlights the existence of a charge plateau for each of the two materials.

[0100] [Fig.2] Fig.2 illustrates the variation of the charge transfer resistance in depending on the state of charge, for the compounds in examples 1, 2 and 3.

[0101] This figure highlights the shift in the peak charge state between the materials of examples 1 and 2 and therefore illustrates the ability of the mixture of example 3 to assist the transitions of the materials of examples 1 and 2.

[0102] [Fig. 3] [Fig. 3] illustrates the electrochemical impedance in a Nyquist-type representation with the first RC-type capacitive loop corresponding to the charge transfer process, the diameter of this loop calculated after simulation of an equivalent RC-type electrical circuit being the charge transfer resistance. EXAMPLES

[0103] The following examples were produced:

[0104] Example 1: LiMno>8Feoj2PC)4

[0105] Example 2: LiMn0.7Fe0.3PO4

[0106] Example 3: mixture of the 2 LMFPs from examples 1 and 2

[0107] A single-electrode pouch-type element with a capacity of 0.1 Ah is manufactured conventionally using the positive electrode manufactured according to the following embodiment: Preparation of the positive electrode:

[0108] An ink is prepared by dispersing an active material of the LMFP type LiMnoFe 0.2PO4 in a liquid medium in an NMP type solvent. A PVDF binder and a material Carbon black-type electronic conductors are added to the dispersion. By varying the amount of solvent incorporated into the mixture, the viscosity of the ink can be varied before it is deposited onto one face of the aluminum current collector. The ink-coated current collector is dried and then laminated to adjust its thickness. After evaporation of the solvent, a layer of active material composition is obtained, the proportions of whose various constituents are typically:

[0109] - 92% by mass of positive active material LiMnOj8FeOj2PO4

[0110] - 4% PVDF binder by mass of binder(s),

[0111] - 4% by mass of electronically conductive material, carbon black type

[0112] Example 2:

[0113] The procedure of Example 1 has been reproduced for LiMnojFeo^PCL

[0114] Example 3:

[0115] An ink is prepared by dispersing two active materials of the LMFP type, LiMnOsFeOsPCLet and LiMnOsFeOsPCLet, in a liquid medium in an NMP-type solvent. A PVDF binder and an electronically conductive material of the carbon black type are added to the dispersion. By varying the amount of solvent incorporated into the mixture, the viscosity of the ink can be varied before it is deposited on one face of the aluminum current collector. The ink-coated current collector is dried and then laminated to adjust its thickness. After evaporation of the solvent, a layer is obtained with a composition of active materials whose proportions of the various constituents are typically:

[0116] - 73.6% by mass of positive active material LiMno^Feo^PCL

[0117] - 18.4% by mass of positive active material LiMno^Feo^PCL

[0118] - of 4% PVDF binder by mass,

[0119] - of 4% by mass of carbon black type electronic conductive material. Beam preparation

[0120] A state-of-the-art negative electrode containing graphite and SBR / CMC type binders is manufactured.

[0121] A state-of-the-art electrolyte containing IM of LiPF6 dissolved in an EC / EMC / DMC type organic solvent mixture in a volume ratio of 1:1:1 is used as the electrolyte.

[0122] A state-of-the-art polyethylene separator is used to electronically separate the electrodes. Measurement of cycling potential

[0123] After assembly of the bundle, filling and sealing according to the state of the art, the element undergoes a constant current electrical forming cycle of C / 10 at 25°C, then a discharge at C / 10, then in a second cycle at C / 10 with charging and discharging between 2.7V and 4.3V. The results are shown in [Fig.1] which illustrates a charging plateau for each of the 2 compositions tested. Measurement of charge transfer resistances

[0124] To measure charge transfer resistances, symmetrical pouch elements are assembled with two opposite positive electrodes of the same state of charge, separated by a state-of-the-art PE-type separator and filled with the same electrolyte. The two electrodes are charged to a predetermined state of charge, corresponding to the points measured in [Fig. 2].

[0125] This figure highlights the absence of a peak in the charge transfer resistance for the mixture in example 3, unlike examples 1 and 2. The composition according to the invention assists the transition of the materials in examples 1 and 2. Impedance measurement

[0126] An electrochemical impedance measurement is then carried out at 25°C by biasing the element at the resting potential obtained after 24h, and by imposing a low amplitude sinusoidal voltage perturbation of + / -10mV in the frequency range of 65kHz to 10'Hz.

[0127] We wait for the element's voltage to stabilize (24h).

[0128] An electrochemical impedance measurement is carried out at equilibrium potential by imposing a sinusoidal perturbation of + / -5mV, in the frequency range from 100kHz to 0.01 Hz.

[0129] The electrochemical impedance is plotted in a Nyquist-type representation on [Fig.3], and the first RC-type capacitive loop corresponds to the charge transfer process, the diameter of this loop calculated after simulation of an equivalent RC-type electrical circuit being the charge transfer resistance.

Claims

Demands

1. Composition of electrochemically active materials comprising at least two active materials of the type lithium manganese iron phosphate (LMFP), each corresponding to the following formula (LMFP1) or (LMFP2), respectively: LisMn, yi Z|Fcv,M lZ|PO4 LisMn, ^ (LMFP1) (LMFP2) wherein M1 and M2, identical or different, are selected from the group consisting of B, Mg, Al, Si, Ca, Ti, V, Cr, Co, Ni, Cu, Zn, Y, Zr, Nb and Mo, Each of the x is identical or different and such that 0.8 < x < 1.2; 0.5 <l-yrZi<l; 0,5<l-y2-z2<l; 0,05< yi <0,5 ; 0,05< y2 <0,5 0< Zi<0,2 ; et 0< z2<0,2 ; Caractérisée en ce que les rapports du fer par rapport au manganèse de LMFP1 et LMFP2 sont distincts et tels que yi> y2 and l-y2-z2>l-yrzi.

2. Composition according to claim 1 such that it contains: from 30 to 95% of compound (LMFP2); and from 5 to 70% of compound (LMFP1); the percentages being by weight relative to the total weight of (LMFP1) and (LMFP2).

3. Composition according to any one of claims 1 or 2 such that it contains: from 60 to 80% of compound (LMFP2); and from 20 to 40% of compound (LMFP1); the percentages being by weight relative to the total weight of (LMFP1) and (LMFP2).

4. Composition according to any one of the preceding claims, in formulas (LMFP1) and (LMFP2), yi and y2 are such that 0.05<(yi -y2)<0.5, preferably 0.1 <(yi - y2)<0.

45.

5. Composition according to any one of the preceding claims such that the compounds (LMFP1) and (LMFP2) are in the form of secondary particles; the size distribution of the secondary particles of (LMFP1) or (LMFP2), respectively, being characterized by a first median volume diameter of the particles Dv50a > 300 nm; the size distribution of secondary particles of (LMFP2) or (LMFP1), respectively, being characterized by a second median volume diameter of particles Dv50b < lOpm.

6. Composition according to any one of the preceding claims, comprising one or more additional active substances selected from the following active substances: - Active substances of the LVPF type meeting the formula (I) Lii+xVi yMyPO4Fzavec 0 <x<0.15, 0<y<0.5, 0.8<z<1.2, et m est choisi parmi le groupe consistant en ti, al, mg, mn, fe, co, y, cr, cu, ni zr;- Active ingredients of the lamellar oxide type corresponding to formula (II): LixMi yz wM'yM”zM'”wO2 (LMO2) where M, M', M” and M'” are chosen from the group consisting of B, Mg, Al, Si, Ca, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Y, Zr, Nb, W and Mo on the condition that at least M or M' or M” or M'” is chosen from Mn, Co, Ni, or Fe; M, M', M” and M'” being different from each other; and 0 <x<l,4 ; 0<y<0,5 0<z<0,5 0<w<0,2 et x+y+z+w<2,l ;- Active substances of the type lithium phosphate of manganese and iron distinct from (LMFP1) and (LMFP2) and corresponding to formula (III): LixMni y zFeyMzPO4 where 0.8 <x<l,2 ; 0,5<l-y-z<l 0<y<0,5 0<z<0,2 m étant un ou plusieurs éléments choisis dans le groupe consistant en al, b, mg, si, ca, ti, v, cr, co, cu, ni, zn, y, zr, nb, w et mo ;- Spinel-type active materials corresponding to formula (IV): LixMn2_y_zM'yM"zO4, where M' and M" are chosen from the group consisting of B, Mg, Al, Si, Ca, Ti, V, Cr, Fe, Co, Ni, Cu, Zn, Y, Zr, Nb and Mo; M' and M" being different from each other, and 1 <x<1,4 ; 0<y<0,6 0<z<0,2.

7. Composition according to any one of the preceding claims comprising, as said additional active ingredient(s), one or several lithiaated nickel oxides chosen from: i) a lithiaated nickel, manganese and cobalt oxide (NMC) of formula Liw(NixMnyCozMt)O2 where 0.9 <w<l,l ; 0<x 0<y 0<z 0<t m étant au moins un élément choisi dans le groupe constitué de al, b, mg, si, ca, ti, v, cr, fe, cu, zn, y, zr, nb, w, mo, sr, ce, ta, ga, nd, pr et la, ii) oxyde lithié nickel, cobalt d’aluminium (nca) formule liw(nixcoyalzmt)o2 où 0,9<w<l,l mn, iii) manganèse, (nmca) liw(nixcoyalzmnt)o2 0<t.

8. Electrode comprising a current collector made of a metal strip which is covered on at least one of its faces by an electrode formulation, said formulation comprising a composition according to any one of the preceding claims.

9. Electrode according to claim 8 such that said formulation comprises one or more conductive material(s), binder(s) and / or additive(s).

10. Electrode according to claim 8 or 9 such that said formulation is in the form of a monolayer.

11. Lithium-ion type electrochemical element comprising at least one electrode according to any one of claims 8 to 10 as a positive electrode.

Images