Positive electrode composition comprising a mixture of active materials of the lithium manganese iron phosphate type

Abstract

The present invention relates to a composition of electrochemically active materials comprising at least two active materials of the lithium manganese iron phosphate (LMFP) type, each corresponding to the following formula (LMFP1) or (LMFP2) having distinct iron contents with respect to manganese, as well as to the electrodes comprising a formulation based on this composition, and to the electrochemical elements containing said electrodes.

Description

[0001] DESCRIPTION

[0002] POSITIVE ELECTRODE COMPOSITION COMPRISING A MIXTURE OF ACTIVE MATERIALS OF THE MANGANESE AND IRON LITHIUM PHOSPHATE TYPE

[0003] 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 intended for positive electrodes, and to ink formulations containing them which are coated on current collectors to manufacture these cathodes.

[0004] The invention is particularly useful in the field of rechargeable electrochemical elements of the lithium-ion (Li-ion) type.

[0005] The electrodes, particularly 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).

[0006] The electrodes are prepared from an ink comprising the composition, generally formulated in an organic solvent medium, coated on a current collector, from which the solvent is evaporated, before calendering so as to adjust the thickness of the ink layer on the collector.

[0007] Lithium phosphates of manganese and iron of formula

[0008] Li x Mni. y .zFe y MzPO4(LMFP) with 0.8 <x<1 ,2 ; 1-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.

[0009] These compounds are known to offer superior safety in use due to the fact that lithium transition metal phosphates are stable at high temperatures.

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

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

[0012] WO2022 / 47705 describes an electrode composition comprising as active materials two phosphate-type materials having the same formula, but with a low manganese content. In order to improve the compression of the electrode, one of the materials is in the form of a single crystal, the other is in the form of a secondary particle.

[0013] It therefore remains to propose compositions based on LMFP type active ingredients 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 making it possible to limit the effects linked 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 lithium manganese and iron phosphate (LMFP) type, each corresponding to the following formula (LMFP1) or (LMFP2), respectively:

[0016] Li x Mni-y i-zi Fe yi M1 zi PO4 Li x Mni- y 2-z2Fe y 2M2 Z 2PO4

[0017] (LMFP1) (LMFP2) in which

[0018] 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,

[0019] Each of the x is the same or different and such that 0.8< x <1.2;

[0020] 0.5<1-yi-zi<1; 0.5<1-y2-Z2<1;

[0021] 0.05< yi <0.5; 0.05< y2 s0.5

[0022] 0< zi <0.2 ; and 0< Z2 <0.2 ;

[0023] Characterized in that the iron to manganese ratios of LMFP1 and LMFP2 are distinct and such that yi>y2 and 1 -y2-z2>1 -yi-zi .

[0024] Thus, the invention proposes a composition comprising several active materials of the LMFP type, having distinct contents of iron compared to manganese, making it possible 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.

[0025] The invention also relates to an electrode comprising a current collector consisting of a metal foil which is covered on at least one of its faces with an electrode formulation comprising a composition according to the invention.

[0026] The invention also relates to an electrochemical element comprising at least one electrode according to the invention as a positive electrode.

[0027] According to other advantageous aspects of the invention, the composition comprises one or more of the following characteristics, taken individually or in all technically possible combinations:

[0028] LMFP type compounds have distinct general formulas, in that they contain different respective iron and / or manganese contents.

[0029] According to one embodiment, (yi / (1 -yi-zi)) is distinct from (y2 / (1-y2-z2)).

[0030] According to a particular embodiment, the material corresponding to the formula (LMFP1) has an iron content greater than the iron content of the material corresponding to the formula (LMFP2).

[0031] According to a particular embodiment, the material corresponding to the formula (LMFP1) has a manganese content lower than the manganese content of the material corresponding to the formula (LMFP2).

[0032] According to a particular mode, (yi / (1 -yi-zi))> (y2 / (1 -y2-z2)).

[0033] According to one embodiment, in formulas (LMFP1) and (LMFP2), x =1.

[0034] According to one embodiment, said composition comprises: from 30 to 95% of compound (LMFP2), in particular from 40 to 85%, particularly from 60 to 80%, more particularly from 65 to 75%; and from 5 to 70% of compound (LMFP1), in particular from 10 to 60%, particularly from 20 to 40%; more particularly from 25 to 35%; the percentages being by weight relative to the total weight of (LMFP1) and (LMFP2).

[0035] According to one embodiment, said composition comprises: from 60 to 80% of compound (LMFP2), particularly from 65 to 75%; and from 20 to 40% of compound (LMFP1), particularly from 25 to 35%; the percentages being by weight relative to the total weight of (LMFP1) and (LMFP2).

[0036] According to one embodiment, said composition comprises: from 65 to 75% of compound (LMFP2); and from 25 to 35% of compound (LMFP1); the percentages being by weight relative to the total weight of (LMFP1) and (LMFP2).

[0037] According to an advantageous embodiment, in the formulas (LMFP1) and (LMFP2), yi and y2 are such that 0.05<(yi - y2)^0.5, preferably 0.1 <(yi - y2)<0.45.

[0038] According to one embodiment, the compounds (LMFP1) and (LMFP2) are in the form of secondary particles.

[0039] 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.

[0040] Nanoparticles typically have a diameter of less than 1000 nm, particularly less than 100 nm.

[0041] According to the invention, the secondary particles of (LMFP1) and (LMFP2) have an identical or different size. Advantageously, (LMFP1) and (LMFP2) have a distinct particle size. Without wishing to be bound by a theory, a different particle size makes it possible to improve the compression of the electrode and therefore reduce its porosity to ultimately increase its electrochemical properties.

[0042] The secondary particles constituting (LMFP1) or (LMFP2), respectively, have a size distribution characterized by a first particle volume median diameter Dv5o a > 300 nm; and the secondary particles constituting (LMFP2) or (LMFP1), respectively, have a size distribution characterized by a second particle volume median diameter Dv5o b < 10pm.

[0043] According to one embodiment, the first median diameter and the second median diameter are identical: Dv5o b / Dv5o a = 1 .

[0044] According to another embodiment, the first median diameter and the second median diameter are different; typically Dv5o b / Dv5o a > 5. According to one embodiment, the volume of secondary particles having the median diameter Dv5o a represents from 10 to 40%, preferably between 15 and 25%, in particular approximately 20% of the total volume of secondary particles constituting (LMFP1) and (LMFP2).

[0045] It is understood that the composition according to the invention may further comprise one or more ingredients.

[0046] Thus, it may include one or more other LMFP type compounds, as active ingredients.

[0047] It may also include one or more other active ingredients distinct from LMFP-type compounds.

[0048] Thus, according to one embodiment, said composition may comprise one or more additional active ingredients, chosen from the following active ingredients:

[0049] LVPF type active ingredients corresponding to the formula (I) Lii+xVi.yMyPCUFzwith 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;

[0050] Active materials of the lamellar oxide type corresponding to the formula (II): LixMi.yz-wM'yM” z M'”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 with the proviso that at least one of 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<1 ,4 ; 0<y<0,5 ; 0<z<0,5 ; 0<w<0,2 et x+y+z+w<2,1 ; plus particulièrement 0,8< x<1 ,4 ;

[0051] Active ingredients of the lithium manganese and iron phosphate type distinct from (LMFP1) and (LMFP2) and corresponding to the formula (III):

[0052] LixMni-y.zFeyMzPCU where 0.8 <x<1 ,2 ; 0,5<1-y-z<1 ; 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 ;

[0053] Spinel-type active materials corresponding to the formula (IV): LixMn2-y-zM'yM" zO4, where M' and M" are selected 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. En particulier, les matières actives de type oxyde lamellaire peuvent être choisies parmi les oxydes lithiés de nickel. Ainsi, selon un mode de réalisation, ladite composition peut comprendre à titre de matière(s) active(s) additionnelle(s) un ou plusieurs oxydes lithiés de nickel choisis parmi : i) un oxyde lithié de nickel, de manganèse et de cobalt (NMC) de formule Liw(NixMn y C0zMt)O2 where 0.9 <w<1 ,1 ; 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, ii) un oxyde lithié de nickel, de cobalt et d’aluminium (NCA) de formule Liw(NixCo yAlzMt)02 where 0.9 <w<1 , 1 ; 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 iii) un oxyde lithié de nickel, de manganèse, de cobalt et d’aluminium (NMCA) de formule Li w (NixC0yAlzMn t )O2 where 0.9 <w<1 ,1 ; 0<x ; 0<y ; 0<z ; 0<t, plus particulièrement 0,83< x.

[0054] The present invention also relates to an electrode comprising the composition according to the invention. Said composition can in fact be included in the composition of an electrode formulation coated on a current collector.

[0055] Typically, said formulation is presented in the form of a monolayer.

[0056] The term "electrode formulation" is thus understood to mean the layer which covers the current collector on at least one of its faces comprising the composition of active materials 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 possible additive(s) in particular.

[0057] According to one embodiment, the current collector consists of a metal strip, solid or perforated, which is covered on at least one of its faces with an electrode formulation, said formulation comprising a composition according to the invention.

[0058] 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 covered on at least one of its faces with an anti-corrosion coating, improving the electronic conductivity and / or improving the adhesion of the layer of active material to the strip. An anti-corrosion coating is understood to mean a layer of material limiting or preventing attack on the strip by moisture, and / or an excessively acidic or basic pH likely to affect the surface condition, integrity or performance of the strip.

[0059] According to one embodiment, said foil is an aluminum foil coated with a carbon coating (Al / C), said coating possibly consisting of amorphous carbon, graphite, carbon fibers, carbon nanotubes and mixtures thereof.

[0060] Typically, the formulation is coated on the face(s) of the strip optionally covered with said coating.

[0061] The coated current collector can therefore be covered on one or each of its faces with said formulation.

[0062] A "binder" is 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.

[0063] 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.

[0064] Said formulation can be prepared from an ink constituted by mixing its ingredients with a solvent.

[0065] According to another object, the present invention also relates to a method for preparing an electrode according to the invention, said method comprising:

[0066] - The preparation of an ink comprising the addition of the ingredients of the electrode formulation to a solvent;

[0067] - the deposition of said ink on the coating of said metal strip;

[0068] - drying; and

[0069] - calendering.

[0070] Generally, an electrode can be manufactured by preparing an ink comprising the composition of active materials, or the active materials, if applicable, mixed with one or more binders, one or more electronically conductive materials, or a solvent. This ink can then be coated on at least one of the faces of a current collector, optionally coated with a coating as described above.

[0071] The ink can then be dried, for example in an oven or furnace.

[0072] 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.

[0073] According to another object, the invention also relates to an electrochemical element of the lithium-ion type comprising at least one electrode as defined above.

[0074] According to one embodiment, said electrode is a positive electrode (cathode) within said element.

[0075] The lithium-ion cell can be manufactured in a conventional manner. At least one cathode, at least one separator, and at least one negative electrode (anode) are superimposed. The assembly can be rolled up to form a cylindrical electrochemical bundle. The invention is not limited to the manufacture of cells in cylindrical format. The cell format can also be prismatic or pouch-type. The electrodes can also be stacked to form a planar electrochemical bundle. A connecting piece is fixed 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 cell container. Conversely, the cathode can be connected to the cell container and the anode to a current output terminal. After being inserted into the cell container, the electrochemical bundle is impregnated with electrolyte. The cell is then sealed.The element may also be conventionally equipped with a safety valve causing the element container to open in the event that the internal pressure of the element exceeds a predetermined value.

[0076] The electrolyte may be liquid and include a lithium salt dissolved in an organic solvent. This lithium salt may be chosen from lithium perchlorate LiCICU, lithium hexafluorophosphate LiPFe, lithium tetrafluoroborate UBF4, lithium hexafluoroarsenate LiAsFe, lithium hexafluoroantimonate LiSbFe, lithium trifluoromethanesulfonate UCF3SO3, lithium bis(fluorosulfonyl)imide Li(FSC>2)2N (LiFSI), lithium trifluoromethanesulfonimide LiN(CFsSO2)2 (LiTFSI), lithium trifluoromethanesulfonemethide LiC(CF3SC>2)3 (LiTFSM), lithium bisperfluoroethylsulfonimide LiN(C2FsSO2)2 (LiBETI), lithium 4,5-dicyano-2-(trifluoromethyl) imidazolide (LiTDI), lithium bis(oxalatoborate) (LiBOB), lithium difluoro(oxalato)borate (LIDFOB), lithium tris(pentafluoroethyl)trifluorophosphate LiPF3(CF2CF3)3 (LiFAP), lithium difluorophosphate UPO2F2 and mixtures thereof.

[0077] The solvent of the electrolyte can be chosen from saturated cyclic carbonates, unsaturated cyclic carbonates, linear carbonates, alkyl esters, ethers, cyclic esters, such as lactones.

[0078] Alternatively, the electrolyte may be solid. It may be a lithium ion-conducting compound, selected 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.

[0079] 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.

[0080] The separator may consist of a layer of polypropylene (PP), polyethylene (PE), polytetrafluoroethylene (PTFE), polyacrylonitrile (PAN), polyester such as polyethylene terephthalate (PET), polybutylene terephthalate (PBT), cellulose, polyimide, glass fibers or a mixture of layers of different natures. The polymers mentioned may be coated with a ceramic layer and / or polyvinylidene difluoride (PVdF) or polyvinylidene fluoride-hexafluoropropylene (PVdF-HFP) or acrylates.

[0081] The invention will appear more clearly on reading the description which follows, given solely by way of non-limiting example, and made with reference to the drawings in which:

[0082] FIGURES

[0083] [Fig 1] Figure 1 represents the variation of voltage as a function of capacitance for the compounds of examples 1 and 2 and highlights the existence of a charge plateau for each of the two materials.

[0084] [Fig 2] Figure 2 illustrates the variation of charge transfer resistance as a function of charge state, for the compounds of Examples 1, 2 and 3. 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.

[0085] [Fig 3] Figure 3 illustrates the electrochemical impedance in a Nyquist-type representation with the first capacitive RC-type 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.

[0086] EXAMPLES

[0087] The following examples were made:

[0088] Example 1: LiMno.sFeo^PCU

[0089] Example 2: LiMno,7Feo,3 PO4

[0090] Example 3: mixture of the 2 LMFPs from examples 1 and 2

[0091] A single-electrode pouch-type cell with a capacity of 0.1 Ah is manufactured in a conventional manner using the positive electrode manufactured according to the following embodiment:

[0092] Preparation of the positive electrode:

[0093] An ink is prepared by dispersing an active material of the LMFP LiMn type Q 8 Fe 0 2PO4 in a liquid medium in an NMP-type solvent. A PVDF binder and an electronically conductive material such as carbon black 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 side of the aluminum current collector. The ink-coated current collector is dried and then rolled to adjust its thickness. After evaporation of the solvent, a layer of an active material composition is obtained, the proportions of the various constituents of which are typically:

[0094] - 92% by mass of positive active material LiMn Q 8 Fe 02 PO4

[0095] - 4% PVDF binder by mass of binder(s),

[0096] - 4% by mass of electronically conductive material, such as carbon black

[0097] Example 2: The procedure of Example 1 was reproduced for LiMn Q 7 Fe0 3 PO4

[0098] Example 3:

[0099] An ink is prepared by dispersing two active materials of the LMFP LiMn type s Fe n .PO. and LiMn7Fe n "PO. in a liquid medium in an NMP type solvent. A PVDF binder and an electronically conductive material such as carbon black are added to the dispersion. By varying the amount of solvent incorporated in the mixture, the viscosity of the ink can be varied before it is deposited on one side of the aluminum current collector. The ink-coated current collector is dried and then rolled to adjust its thickness. After evaporation of the solvent, a layer of an active ingredient composition is obtained, the proportions of the various constituents of which are typically:

[0100] - 73.6% by mass of positive active material LiMn Q 8 Fe 02 PO4

[0101] - 18.4% by mass of positive active material LiMn Q 8 Fe 02 PO4

[0102] - 4% PVDF binder by mass,

[0103] - 4% by mass of carbon black type electronic conductive material.

[0104] Beam preparation

[0105] A state-of-the-art negative electrode containing graphite and SBR / CMC type binders is manufactured.

[0106] A state-of-the-art electrolyte containing 1M LiPF6 dissolved in an EC / EMC / DMC type organic solvent mixture in a volume ratio of 1:1:1 is used as the electrolyte.

[0107] A state-of-the-art polyethylene type separator is used to electronically separate the electrodes.

[0108] Measurement of potential in circuit

[0109] After assembly of the bundle, filling and closing according to the state of the art, the element undergoes a constant current electrical formation cycle from C / 10 to 25°C, then a discharge at C / 10, then a second cycle at C / 10 in charge and discharge between 2.7V and 4.3V. The results are shown in Figure 1 which illustrates a charge plateau for each of the 2 compositions tested.

[0110] Measurement of charge transfer resistances To measure charge transfer resistances, symmetrical pouch elements are assembled with two positive electrodes of the same state of charge facing each other, separated by a state-of-the-art PE-type separator and filled with the same electrolyte. Both electrodes are charged to a given state of charge, corresponding to the points measured in Figure 2.

[0111] This figure highlights the absence of a peak in charge transfer resistance for the mixture of Example 3 unlike Examples 1 and 2. The composition according to the invention assists the transition of the materials of Examples 1 and 2.

[0112] Impedance measurement

[0113] An electrochemical impedance measurement is then carried out at 25°C by polarizing the element at the resting potential obtained after 24 hours, and by imposing a low amplitude sinusoidal voltage disturbance of + / -10mV in the frequency domain of 65kHz to 10 _ 1 Hz.

[0114] We wait for the element voltage to stabilize (24 hours).

[0115] An electrochemical impedance measurement is carried out at the equilibrium potential by imposing a sinusoidal disturbance of + / -5mV, in the frequency domain ranging from 100kHz to 0.01 Hz.

[0116] The electrochemical impedance is plotted in a Nyquist-type representation in Figure 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

CLAIMS 1. Composition of electrochemically active materials comprising at least two active materials of the lithium manganese and iron phosphate (LMFP) type, each corresponding to the following formula (LMFP1) or (LMFP2), respectively: Li x Mni- y i-zi Fe yi M1 zi PO4 Li x Mni- 2-z2Fe 2M2 Z 2PO4 (LMFP1) (LMFP2) in which 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, Each of the x is the same or different and such that 0.8< x <1.2; 0.5<1-yi-zi<1; 0.5<1-y2-Z2<1; 0.05< yi <0.5; 0.05< y2 s0.5 0< zi <0.2 ; and 0< z2<0.2 ; Characterized in that the iron to manganese ratios of LMFP1 and LMFP2 are distinct and such that yi>y2 and 1 -y2-z2>1 -yi-zi .

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 the 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 secondary particle size distribution of (LMFP1) or (LMFP2), respectively, being characterized by a first volume median particle diameter Dv5o a > 300 nm; the secondary particle size distribution of (LMFP2) or (LMFP1), respectively, being characterized by a second volume median particle diameter Dv5o b < 10pm.

6. Composition according to any one of the preceding claims such that it comprises one or more additional active ingredients, chosen from the following active ingredients: LVPF type active ingredients corresponding to the formula (I) Lii+xVi.yMyPCUFzwith 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 the formula (II): LixMi-yz-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 with the proviso that at least one of 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<1 ,4 ; 0<y<0,5 ; 0<z<0,5 ; 0<w<0,2 et x+y+z+w<2,1 ; Active ingredients of the lithium manganese and iron phosphate type distinct from (LMFP1) and (LMFP2) and corresponding to the formula (III): LixMni-y.zFeyMzPCU where 0.8 <x<1 ,2 ; 0,5<1-y-z<1 ; 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 the formula (IV): LixMn2-y-zM'yM" zO4, where M' and M" are selected 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 material(s) one or more lithium nickel oxides chosen from: i) a lithium oxide of nickel, manganese and cobalt (NMC) of formula Liw(NixMn y C0zMt)O2 where 0.9 <w<1 ,1 ; 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) un oxyde lithié de nickel, de cobalt et d’aluminium (NCA) de formule Liw(NixCo yAlzMt)02 where 0.9 <w<1 , 1 ; 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, et iii) un oxyde lithié de nickel, de manganèse, de cobalt et d’aluminium (NMCA) de formule Li w (NixC0yAlzMn t )O2 where 0.9 <w<1 ,1 ; 0<x 0<y 0<z 0<t.

8. Electrode comprising a current collector consisting of a metal foil which is covered on at least one of its faces with 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. Electrochemical element of lithium-ion type comprising at least one electrode according to any one of claims 8 to 10 as positive electrode.

Images