CARBON MATERIAL, USE OF IT IN BATTERIES, METHOD FOR PRODUCING THIS MATERIAL AND ELECTRODES USING IT

Description

[0001] The invention relates to a carbonaceous material comprising hard, non-porous carbon particles of small spherical morphology and its use as a material in electrochemical devices such as electrochemical cells, batteries and / or sodium ion accumulators.

[0002] Hard carbon is a disordered form of carbon (neither graphite nor diamond) that cannot be graphitizable even when heated to very high temperatures (3000°C). It consists of a mixture of randomly stacked monolayer and unstacked monolayer regions of carbon atoms, and has an overall low degree of graphitization. These carbons are generally manufactured by pyrolysis of carbon precursors such as sugars, biomass waste, polymers, and phenolic resins. The use of hard carbon as a material in the field of electrochemistry has been studied for many years. Its availability, cost, corrosion resistance, and good electronic conductivity make it a very promising material for the manufacture of electrodes for fuel cells, fuel cells, and batteries.In particular, this material is promising for the production of sodium ion batteries because it allows the reversible intercalation of sodium ions. Thus, A. Beda et al., "Hard carbons derived from green phenolic resins for Na-ion batteries," Carbon, vol. 139, pp. 248-257, Nov. 2018 describes a carbon material that is a hard carbon obtained by polymerization of a polyphenol, phloroglucinol, and an aldehyde, glyoxylic acid. The three-step process produces a material consisting of heterogeneously shaped particles that, after grinding, can be used in sodium ion batteries.

[0003] In the technical field, the following documents can also be cited: US2003 / 157014; CN102386384; CN2015914371; CN103996833; LIFEN XIAO et al: "Low-Defect and Low-Porosity Hard Carbon with High Coulombic Efficiency and High Capacity for Practical Sodium lon Battery Anode", Advanced Energy Materials, vol. 8, no. 20, page 1703238; E. IRISARRI et al., Journal of The Electrochemical Society, (20180000), vol. 165, no. 16, pages 4058 - 4066.

[0004] Furthermore, Maetz et al., "Facile and Sustainable Synthesis of Nitrogen-Doped Polymer and Carbon Porous Spheres," Green Chem., 2017, vol. 19, pp. 2266-2274) describes the synthesis of porous carbon spheres by polymerization of phloroglucinol and glyoxylic acid using Triethylenediamine (TEDA) as a reaction catalyst. The synthesis process does not require a thermopolymerization step. The resulting material is not suitable for use in electrodes, particularly due to its high porosity.

[0005] However, for a material to be used for electrodes, and in particular sodium ion type electrodes, the material must have specific physicochemical characteristics in order to be efficient. In particular, the material must allow simple and inexpensive manufacture of electrodes and make it possible to obtain rechargeable batteries, batteries or accumulators, in particular of the sodium ion type, having an acceptable irreversible and reversible capacity.

[0006] For this purpose, the subject of the invention is a carbon material, comprising, consisting essentially of, or consisting of, hard, non-porous carbon particles having a spherical morphology, this material having an inter-reticular distance d 002 of between 3.50 Å and 4.30 Å, and a total specific surface area, measured by the BET N2 method, of less than 75 m 2 < / g.

[0007] Such a material presents by these characteristics a substantial ease of use compared to existing carbon materials because this material is simple to obtain and this from low-polluting compounds and its particular and homogeneous morphology ensures a high reproducibility during the manufacture of the electrode. In addition its manufacturing method, which is also an object of the invention allows the direct obtaining of a homogeneous powder without grinding steps, and particularly industrial and / or mechanical grinding, of the material resulting from the carbonization. Indeed, the hard carbon resulting from conventional manufacturing methods is present, after the carbonization step in the form of a mass or an agglomerate of very hard pieces which it is necessary to reduce to powder for its use in electrodes. This grinding step, when carried out at an industrial level, must necessarily be done by machine.The use of such machines, such as ball mills, can degrade hard carbon by increasing its structural defects and / or by increasing the presence of functional oxygenated groups (CO x ). The carbon material according to the invention, which does not require such an industrial grinding step for its manufacture, therefore preserves its intrinsic qualities and can be used directly. Thus, according to a preferred aspect of the invention, the material is a powder, advantageously a powder whose average apparent grain size is less than 10 µm, and preferably varies from 1 to 10 µm.

[0008] The hard carbon according to the invention is a so-called "disordered" type of carbon which is non-graphitizable (ordered structure) even when heated at high temperature (1g at more than 2000C° for 1 hour under Argon). The structure of hard carbons is disordered when compared to highly ordered crystalline structures (e.g. graphite type) or slightly disordered (graphitizable carbon, or "soft" carbon). However, even these hard carbons have more ordered graphitic-type zones (i.e. stacked graphene planes), which may explain some of their electrochemical properties. An inter-reticular distance d 002 greater than 3.5 Å is generally a characteristic of a hard carbon, since the d 002 distance of graphite is 3.34 Å and that of soft carbons varies from about 3.45 to 3.6 Å.Beyond an interlattice distance d 002 of 4.3 Å, carbon is too disorganized and is generally no longer suitable for use as an electrode material.

[0009] The particles of the carbonaceous material according to the invention have a spherical morphology. By spherical morphology is meant that these particles have an essentially spherical shape. For example, the distance between the surface and the center of gravity of the particle (radius) must not vary by more than 10%, preferably 5%. These spheres are most of the time microspheres, that is to say that their diameters are essentially of the order of 0.1 to 100 microns, but other dimensions could be envisaged.

[0010] Preferably the interreticular distance, which is preferably measured by X-ray diffraction, XRD (see below), is greater than 3.6 Å. According to a preferred aspect this distance is between 3.70 Å and 4.00 Å, advantageously is chosen in a range from 3.75 Å to 3.90 Å, and even more preferably in a range from 3.80 Å to 3.90 Å. The very particularly preferred interreticular distance varies from 3.70 Å to 3.80 Å.

[0011] The total specific surface area of ​​the material according to the invention, measured by the BET N 2 method, is preferably from 1 to 50 m 2 < / g, in particular from 1 to 10 m 2 < / g and even more preferably from 1 to 3.5 m 2 < / g.

[0012] According to a preferred aspect, the total specific surface area, measured by the BET CO 2 method, of the material according to the invention is from 1 to 100 m 2 < / g, preferably from 1 to 60 m 2 < / g, in particular from 1 to 21 m 2 < / g, and very preferably from 1 to 10 m 2 < / g.

[0013] A particularly preferred feature of the invention is that the carbonaceous material has a tapped density (in English " tapped density”), or compacted density, which is particularly high compared to other known carbon materials. In fact, the material can have a tapped density similar to other materials used at the industrial level and this in particular without a prior grinding step, a step which generally tends to degrade the properties of the material. Thus, the material according to the invention advantageously has a tapped density greater than 0.7 g / cm 3< , for example which is chosen in the range of 0.72 g / cm 3< to 1.1 g / cm3, preferably greater than 0.84 g / cm 3< . The measurement procedure, which is a standard method, is described below.

[0014] The hard carbon particles essentially have a size between 0 µm and 15 µm, preferably between 0 µm and 10 µm. According to one aspect of the invention, the particle distribution is homogeneous and the average D50 value of the particles can range from 0.4 µm to 5 µm, preferably from 1.5 µm to 4.5 µm or from 3.5 µm to 4.5 µm, in particular approximately 3.8 µm. According to another aspect of the invention, which is preferred, the particle size distribution is not homogeneous but comprises at least 2 distinct particle peaks. A first predominant peak comprises small-sized particles (generally approximately 4 ± 0.5 µm) with a broader peak towards the larger sizes (generally approximately 7 ± 0.5). The average particle size constituting these peaks are for example respectively 2.5 to 4 µm and 7.1 to 7.7 µm. Preferably the ratio of these sizes has a ratio of approximately 2.8 ± 20.Such particle distribution is particularly advantageous because it allows for increased density.

[0015] The material according to the invention advantageously has a low active surface area (ASA), preferably less than 12m 2 < / g, and even more preferably less than 5 m 2 < / g and even less than 3 m 2 < / g and even 1 m 2 < / g.

[0016] Finally, the material according to the invention advantageously has a very low content of oxygen-based functional groups, in particular less than 0.5 mmol / g, preferably less than 0.1 mmol / g, in particular less than 0.05 mmol / g.

[0017] The material described below and referenced under the name ABE 1300, ABE 1400, ABE 1500 or ABE 1600, is a particularly preferred material according to the invention. In particular, ABE 1500°C is particularly suitable for use as an electrode and more particularly as an anode in sodium ion batteries. Another aspect of the invention is a method for manufacturing a non-porous carbon material comprising at least the following steps: a. a step of mixing, in the presence of a solvent, in particular an aqueous solvent, at least one amine catalyst preferably chosen from the group consisting of Triethylenediamine (TEDA), hexamethylenetetramine (HMTA), quinuclidine, triethylamine (TEA) and mixtures thereof, advantageously said catalyst is TEDA, even more advantageously the catalyst is HMTA; a carbon source (or capable of forming carbon after pyrolysis) such as a hydroxylated aromatic compound chosen in particular from the group consisting of phenol, resorcinol and phloroglucinol, catechin, pyrogallol, hydroxyquinol, gallic acid, polyphenols, such as tannins, and mixtures thereof, advantageously said hydroxylated aromatic compound is phloroglucinol, or a condensed tannin;and an aldehyde compound, preferably selected from the group consisting of glyoxal, formaldehyde, acetaldehyde, a ketoacid, glyoxylic acid, pyruvic acid, 2-methyl-3-oxopropanoic acid, and mixtures thereof, preferably the aldehyde compound is glyoxylic acid; b. a step of maturing the mixture obtained at the end of step a), preferably at a temperature of between 20 and 35°C, for example for a period of between 0.5 and 5 days, allowing the production of a solid phase comprising spheres of phenolic resin and a liquid phase; c. a step of controlled separation of said solid phase from said liquid phase, preferably without centrifugation; d. a step of polymerization and / or drying, optionally thermal, of said solid phase for a period of 1 to 48 hours, resulting in the formation of a dry phenolic resin;and e. a step of carbonizing said dry phenolic resin, preferably in the presence of a flow of inert gas at a temperature preferably between 1200°C and 2000°C to obtain a non-porous carbon material; and f. optionally a step of recovering said non-porous carbon material. The solvent is advantageously a polar protic solvent, which may be chosen from water and / or alcohols (such as ethanol, propanol and butanol), alone or in a mixture, although an unmixed solvent (i.e. at least 95% v / v pure), for example ethanol, is preferred. ;

[0018] The solvent is preferably an aqueous solvent, more specifically water, pure or simply potable (and therefore including certain salts). Preferably the solvent is water, and more specifically pure water.

[0019] The amount of solvent, in particular water, relative to the phenolic precursor (1 g) may optionally be chosen in the range from 10 to 200 g, preferably from 20 to 60 g, (or a water:precursor mass ratio of 20:1 to 60:1).

[0020] The quantity of crosslinking agent (aldehyde) relative to the phenolic precursor (1g) may optionally be chosen in the range from 0.5 to 4 g, preferably from 0.8 to 1.8 g (i.e. from 0.88 to 1.8 in mass percentage relative to the total mass of precursor (i.e. a mass ratio of crosslinking agent: precursor ranging from 0.88:1 to 1.8:1).

[0021] The amount of catalyst (amine agent) relative to the phenolic precursor may optionally be chosen in the range from 0.1 to 0.9 g, preferably from 0.3 to 0.7 g.

[0022] The hydroxylated aromatic compound may also be selected from benzene ring compounds having a hydroxy group. The benzene ring may not be substituted other than by the hydroxy group (a "phenol" type compound), or substituted by one or more groups, such as the following: hydrocarbon, halogen, nitro, amino, and / or alkoxy group. Such compounds include phenol, halophenols, aminophenols, hydrocarbyl-phenols ("hydrocarbyl" including, for example, linear, branched or cyclic groups of the alkyl, alkenyl, or alkynyl type containing, for example, from 1 to 6 carbons, optionally substituted by one or more oxygen or nitrogen atoms, naphthols, nitrophenols, hydroxyanisoles, hydroxybenzoic acids, phenols substituted by one or more fatty acid esters, one or more polyalkyleneoxy, phenols containing an azo linkage (p-hydroxyazobenzene), phenolsulfonic acids (p-phenolsulfonic acid).These compounds include fluorophenols, chlorophenols, bromophenols, and iodophenols, 2-, 3-, and 4-aminophenols, 3,5- and 2,5-diaminophenols; 2-, 3-, and 4-nitrophenols, 2,5- and 3,5-dinitrophenol; cresols, methylphenols or hydroxytoluenes, xylenols, ethylphenols, n-propylphenols, isopropylphenols, butylphenols, hexylphenols, octylphenols, nonylphenols (, phenylphenols, hydroxycinnamic acids; hydroxyanisoles such as 2-methoxyphenol, 3-methoxyphenol, 4-methoxyphenol, 3-t-butyl-4-hydroxyanisole; 2-hydroxybenzoic, 3-hydroxybenzoic, 4-hydroxybenzoic acids, and their esters (methyl salicylate and ethyl-4-hydroxybenzoate).

[0023] Examples of phenolic compounds with two hydroxy groups are: catechol, resorcinol, hydroquinone, hydrocarbyl bisphenols (such as bisphenol A, methylenebisphenol, and 4,4'-dihydroxystilbene), 4,4'-dihydroxybiphenyl (4,4'-biphenol), halo diphenols (2-haloresorcinols, 3-haloresorcinols, and 4-haloresorcinols, where halo is fluoro, chloro, bromo, or iodo), amino diphenols (2-a minoresorcinol, 3-a minoresorcinol, and 4-a minoresorcinol), hydrocarbyl diphenols (2,6-dihydroxytoluene, 2-methylresorcinol; 2,3-, 2,4-, 2,5-, and 3,5-dihydroxytoluene, 1-ethyl-2,6-dihydroxybenzene, caffeic or chlorogenic acid), nitro-diphenols (2- or 4-nitroresorcinol), dihydroxyanisoles (3,5-, 2,3-, 2,5-, or 2,6-dihydroxyanisole, vanillin), dihydroxybenzoic acids (3,5-, 2,3-, 2,5-, or 2,6-dihydroxybenzoic acids), and their esters, vanillic acid, phenolphthalein.

[0024] Examples of compounds comprising three hydroxy groups are: phloroglucinol (1,3,5-trihydroxybenzene), pyrogallol (1,2,3-trihydroxybenzene), 1,2,4-trihydroxybenzene, 5-chloro-1,2,4-trihydroxybenzene, resveratrol (trans-3,5,4'-trihydroxystilbene), hydrocarbyl-triphenols (2,4,6-trihydroxytoluene, methylphloroglucinol, and 3,4,5-trihydroxytoluene), halo-triphenols (5-chloro-1,2,4-trihydroxybenzene), carboxy-triphenols (3,4,5-trihydroxybenzoic and 2,4,6-trihydroxybenzoic acids), nitro-triphenols (2,4,6-trihydroxynitrobenzene), and phenol-formaldehyde resoles or novolak-type resins.

[0025] Examples of compounds containing a multitude of hydroxyl groups are: tannins (incl. tannic acid), ellagotanins, gallotannins, phenol polymers (poly-(4-hydroxystyrene), phenol-formaldehyde resoles or novolak-type resins containing at least four phenol groups (usually MW 500-5000), quercetin, ellagic acid and tetraphenol ethane. Tannins are a group of naturally occurring molecules from plants and are readily available. They are polyphenols with high molecular weights, generally ranging from 500 to 20,000 g / mol. They can be characterized in particular by the presence of at least 12 hydroxyl groups -OH and 5 phenyl groups. Among the tannins, a distinction is made between hydrolyzable tannins, phlorotannins and condensed tannins. Hydrolyzable tannins (pyrogallol) contain glucose residues which are esterified and no more -OH group.Phlorotannins contain phloroglucinol groups and are generally extracted from brown algae. Condensed tannins (catechol and phlobotannins), also called proanthocyanidins, which contain flavan-3-ol groups. Condensed tannins and phlorotannins are the most suitable tannins for use in the process according to the invention and in particular condensed tannins such as mimosa or catechu tannins. To distinguish condensed tannins from hydrolyzable tannins, it is possible to perform their FT-IR spectra. Hydrolyzed tannins have a -C=O peak at 1730 cm -1< , and possibly a -CO° peak at 1250 cm -1< , peaks which are absent, or less accentuated for condensed tannins.

[0026] As previously indicated, phloroglucinol and condensed tannins, especially those of mimosa and catechu, are particularly preferred.

[0027] The compound may also be selected from aldehyde, dialdehyde, and polyaldehyde compounds. They may be represented by the following formulas: R-CHO where R is a linear, branched, or cyclic group of the alkyl, alkenyl, or alkynyl type containing at least 1, 2, 3, 4, 5, 6, 7, or 8 carbon atoms. Such examples include: acetaldehyde, propanal (propionaldehyde), butanal (butyraldehyde), pentanal (valeraldehyde), hexanal, crotonaldehyde, acrolein, benzaldehyde, and furfural; OHC-R-CHO where R is a covalent bond (glyoxal) or a linear, branched, or cyclic group of the alkyl, alkenyl, or alkynyl type containing at least 1, 2, 3, 4, 5, 6, 7, or 8 carbon atoms. Such examples include: glyoxal, malondialdehyde, succinaldehyde, glutaraldehyde, adipaldehyde, pimelaldehyde, suberaldehyde, sebacaldehyde, cyclopentanedialdehyde, terephthaldehyde, and furfuraldehyde.Alternatively, one of the hydrogens of the aldehyde compound may be replaced by a hydrocarbon group, for example to form an aldehyde ketone dione, for example methylglyoxal or 1,3-butanedione.

[0028] An advantageous variant of the aldehyde compound to be used in the process of the invention comprises the use, as, or among, the aldehydes described above, of at least one organic compound comprising both an acid function and an aldehyde function. Mention may thus be made of organic compounds comprising both an acid function and an aldehyde function of the following formula ("keto acids"): HOOC-R-CHO where R is present or absent, and if present, represents a saturated, linear, branched or cyclic hydrocarbon chain, preferably C1-C20, optionally substituted, optionally having one or more unsaturations, optionally including one or more heteroatoms and / or functions.

[0029] In the process according to the invention, the aldehyde plays the role of main crosslinking agent, it can therefore be capable of forming a phenolic resin using the phenol units of the carbon precursor compounds.

[0030] The term "substituted" means one or more substitutions of a hydrogen atom by a halogen atom or by a group such as, for example: alkyl, haloalkyl, cycloalkyl, alkenyl, alkynyl, aryl, a heterocyclic group, such as heterocycloalkyl, heteroaryl, or by one or more side functions, such as, for example, amine, cyano, acid, ester, amide functions, etc., without particular limitation.

[0031] The term "function" means a chemical group modifying at least one chemical property, such as for example an amide, ester, oxo, etc. function, without particular limitation.

[0032] According to a variant, R is present or absent, and if present, represents a linear, branched or cyclic alkyl chain, preferably C1-C20, optionally substituted. Among the alkyl groups, mention may be made of: methyl, ethyl, propyl, and butyl, or pentyl, hexyl, octyl, nonyl, decyl, dodecyl, hexadecyl, octadecyl, isopropyl, iso-butyl, sec-butyl, tert-butyl, 2-ethylhexyl, 2-methylbutyl, 2-methylpentyl, 1-methylpentyl and 3-methylheptyl.

[0033] These compounds include alpha-ketoacids, or 2-oxoacids (pyruvic acid); beta-ketoacids or 3-oxoacids (acetoacetic acid); gamma-ketoacids or 4-oxoacids (levulinic acid).

[0034] Examples of such compounds include: Glyoxylic acid: HOOC-CHO; Pyruvic acid: HOOC-CH2-CHO; and 2-methyl-3-oxopropanoic acid.

[0035] The step of mixing the components may include a preliminary step of dissolving the carbon source and in particular the hydroxylated aromatic compounds and / or aldehyde in the solvent, these steps being carried out with stirring. The dissolution time may vary from a few minutes (e.g. 5 minutes) to several hours (e.g. 5 hours). A period of 0.5 to 1 hour may be sufficient. The addition of the catalyst may then be carried out with stirring as well. The stirring period is generally shorter. In general, it is chosen from 1 minute to 1 hour, in particular from 5 to 15 minutes. It should be noted that the term catalyst is used to designate the main function of the amine compound which is to catalyze the crosslinking reaction between the carbon precursor and the main crosslinking agent, for example the aldehyde.However, this amino compound can also, but to a lesser degree, participate in crosslinking and thus be considered a secondary crosslinking agent.

[0036] Step b) of maturation of the mixture obtained at the end of these steps can be carried out at room temperature (approx. 20 to 25°C), which is an advantage in terms of costs. Preferably, the maturation reaction takes place at rest and not with stirring. It may also be advantageous to work in a controlled atmosphere, and in particular to close the container containing the mixture or to work under inert gas, this to avoid evaporation of the solvent. The maturation step advantageously lasts more than 24 hours. A maturation step of 36 to 72 hours, and more particularly of 44 to 52 hours (for example 48 hours) is preferred.

[0037] Step c) of separating the solid phase, or resin, from the liquid phase is preferably carried out by gentle methods, for example by simple pouring (or suction) of the liquid may be sufficient. The solid phase remains attached to the walls of the container. Advantageously, it may be recommended not to apply centrifugation means for particles of a sufficient size (for example more than 1 micron). Thus, it is recommended according to a particularly preferred aspect of the invention not to apply a high force to the resin such as for example high-speed centrifugation, for example beyond 10 to 15 thousand revolutions / minute. Step d), which is a polymerization and / or drying step, is preferably a thermal step. This thermal step is preferably gentle and may take place by heating to a temperature ranging from 70°C to 150°C.Advantageously, this temperature is chosen in a range from 75°C to 85°C, in particular around 80°C. The thermal step can be carried out at rest and is preferably chosen to reduce the cost and the steps of the synthesis. The heating time can be from 6 to 24 hours, and preferably from 8 to 16 hours, for example about 10 or 12 hours.

[0038] When drying / polymerizing at room temperature the drying time can vary from 10 to 48 hours, for example a period of 20 to 24 hours gives satisfactory results.

[0039] At the end of this step, the dry resin thus obtained is subjected to a carbonization step. By carbonization is meant a pyrolysis or thermolysis step. The carbonization temperature can advantageously be chosen in the range of 1300°C to 2000°C. This carbonization preferably takes place in an oxygen-free atmosphere, and preferably under argon. The temperature variation can advantageously be from 1°C / min to 15°C / min, preferably around 5°C / min. The use of a temperature of around 1500°C, for example ± 20%, makes it possible to obtain a material particularly suitable for use as an electrode and more particularly as an anode in sodium ion batteries.

[0040] Once the carbonization step is completed, the carbonaceous material is obtained. It is generally in the form of a powder and can be recovered by simple collection. Such a powder can be used directly in the manufacture of electrodes for a device, particularly an electrochemical device, without having to undergo a substantial grinding step as is usually practiced.

[0041] Another object according to the invention is therefore a carbon material obtained or obtainable by the process according to the invention.

[0042] A carbon material according to the invention can advantageously be used in the manufacture of an electrode or an electrode material, preferably an electrode for a rechargeable battery (or cell), in particular for sodium-ion, lithium-ion, potassium-ion or Li-S batteries. It can also be used as an additive and combined with one or more other materials in a device and in particular an electrochemical device. Such use as well as such an electrode are other objects of the invention.

[0043] According to a preferred embodiment of the invention, the electrode has a porosity after calendering (and possibly pelletizing) of less than 65%, preferably less than 55%, advantageously less than 48% and even more preferably less than 44%. This porosity can therefore be from 30% to 65%, preferably from 35% to 55%, advantageously from 35% to 50%.

[0044] According to a preferred embodiment of the invention, the electrode, when used in a sodium-in half-cell (Na cathode), has a low irreversible capacity, and in particular less than 14%, preferably less than 12% and advantageously less than 9%. In a particularly preferred manner, this capacity reaches approximately 8%.

[0045] According to a preferred embodiment of the invention, the electrode, when used in a complete sodium-ion cell (NVPF cathode), has a high specific capacity, which can range from 100 mAh.g -1< to 140 mAh.g -1< , which can be equal to 125 mAh.g -1< .

[0046] Thus, an electrode according to the invention comprises the carbon material as described above. It may advantageously comprise one or more materials, such as a conductive additive (for example carbon black) and / or a binder (for example a polymer such as PolyVinyliDene Fluoride, PVDF). According to a variant of the invention, no conductive additive is present. Such an electrode may contain a majority of carbon material according to the invention, in particular more than 80% by mass, preferably more than 90%, for example approximately 97% of carbon material. This quantity is therefore advantageously from 80% to 99%, preferably from 85% to 98%, for example from 88% to 94%. The quantity of conductor may vary from 0% to 10%, preferably from 2% to 5%. The quantity of binder may vary from 1% to 10%, preferably from 2% to 5%.Preferably, the manufacture of such an electrode optionally comprises the mixing of its constituent elements and advantageously a step of calendering the material or mixture to obtain an electrode according to the invention. Such a manufacturing method is also an object of the invention.

[0047] Another subject of the invention is a battery, an accumulator or a cell, possibly rechargeable, or an electrochemical device comprising either the carbon material according to the invention, or an electrode according to the invention. Brief description of the figures

[0048] The invention will be better understood with the aid of the examples of implementation of the invention and the attached drawings in which: [ Fig. 1 ] there Figure 1 is a diagram of a method according to the invention for manufacturing a carbon according to the invention. Fig. 2 ] there Figure 2 is an image obtained by SEM of a carbon according to the invention ABE 1300 (scale 20 µm). [ Fig. 3 ] there Figure 3 is an image obtained by SEM of a known carbon, HC-water. [ Fig.4 a and b] the Figure 4a is an image obtained by SEM of the carbon according to the invention ABE 1300 which also includes a graph 4b representing the distribution of the particles. Fig.5 a and b] the Figure 5b is an image obtained by SEM of a carbon according to the invention obtained using the same process as ABE 1300 but without a thermal step at 80°C and which also includes a graph 5a representing the distribution of the particles. Fig.6 ] there Figure 6 is an exploded view of the assembly of a half-cell configuration according to the invention. Fig.7 ] there Figure 7 is an exploded view of the assembly of a configuration of a battery according to the invention. Fig. 8 ] there figure 8 shows the performance of the half cell using the ABE 1400 material according to the invention, C / 50 at 25°C. [ Fig. 9 ] there Figure 9shows the performance of the half cell using the ABE 1500 material according to the invention C / 50 at 25°C. [ Fig. 10 ] there Figure 10 shows the performance of the half cell using the ABE 1600 material according to the invention C / 50 at 25°C. [ Fig. 11 ] there Figure 11 shows the performance of the half cell using a hard carbon PAC2 C / 50 at 25°C. Fig. 12 ] there Figure 12 shows the galvanostatic cycling pattern of the complete cell made with ABE 1300 material during formation at C5 & D5 [ Fig. 13 ] There Figure 13 shows the retention of the complete cell achieved with the ABE 1300 material in galvanostatics (formation C5 & D5 over 5 cycles then 1C & 1D over 100 cycles) [ Fig. 14 ] there figure 14 shows the retention of the complete cell achieved with the ABE 1300 material in galvanostatics at different charge regimes and with a constant discharge regime [ Fig. 15 ] there Figure 15shows the retention of the complete cell achieved with the ABE 1300 material in galvanostatics at different discharge regimes and with a constant charge regime. Fig. 16 ] : there figure 16 are images obtained by SEM of carbons according to the invention obtained according to the method described in example 3bis. [ Fig. 17 ] there Figure 17 is an image obtained by SEM of the carbons according to the invention MC-00 and MC-01 and which also include a graph representing the distribution of the particles. Fig. 18 ] there figure 18 is an image obtained by SEM of the carbons according to the invention MC-00, MC-04 and MC-05 and which also include a graph representing the distribution of the particles. Fig. 19 ] there figure 19 is an image obtained by SEM of the carbons according to the invention MC-0524, MC-05 and MC-0572 and MC-0597 and which also include a graph representing the distribution of the particles. Fig. 20 ] There figure 20represents the FT-IR spectra of different hydrolyzable tannins (chestnut, myrobalan, tara) measured on a Jasco FT / IR-4100 spectrophotometer, using a “Jasco Spectra Manager” management program and a resolution of 0.4 cm -1< . Example 1 : Syntheses of carbon materials according to the invention

[0049] 4.1g of phloroglucinol and 3.6g glyoxylic acid were dissolved in 200 mL (g) water under mechanical stirring (~30 min -1h) at room temperature (25°C) in a flask. Then, 1.8g of triethylenediamine, (TEDA) was added into this mixture and stirred for about 5-10 min until complete dissolution. The addition of TEDA as a crosslinking agent / catalyst causes the formation of a turbid solution of phenolic resin spheres. The mixture is left to stand for an aging time of 24h. The spheres increase in size and weight and settle on the bottom of the flask. Two phases are observed: a solid phase (composed of polymer spheres) and a liquid phase. The latter is removed and the solid phase recovered (without centrifugation, by simple pouring) and dried in an oven at 80°C for around 12 hours to evaporate the water and to better crosslink the resin spheres.A pyrolysis step was then carried out in an inert atmosphere (Ar), by heating 6.5 g of the resin obtained with a heating rate of 5°C / min up to 1300°C, 1400°C, 1500°C or 1600°C and once the desired temperature is reached a one-hour (1h) plateau is made then a natural cooling step is carried out. The hard carbon is thus obtained (~ 2.5 g) is used subsequently without the need for a grinding step to standardize the particle size.

[0050] The materials obtained are called ABE1300, ABE 1400, ABE 1500 and ABE 1600.

[0051] It is noted that the ABE 1300 hard carbon was synthesized in larger quantities (30g) and that this change of scale did not produce any notable change in the structure or morphology of the hard carbon thus obtained. Five other materials according to the invention were synthesized with condensed mimosa and catechu tannins as precursors. The spectra of the figure 20 highlight the structural differences between condensed tannins and hydrolyzable tannins. Mimosa-G (MG) and Cachou (C) materials were purchased from GREEN'ING (France) while Mimosa-C (MC) material was obtained from Mimosa Extract Company Ltd. Hydroxy aromatic material Type of tannin Constituents Main structural unit Mimosa-C (MC) (Acacia mearnsii) Condensed 66% condensed tannins Tannin Mimosa-G (MG) (Acacia mearnsii) Condensed Tannin 60 to 65% condensed tannins Cachou (C) (Acacia catechu) Condensed Condensed tannins + flavonols (quercitrin) Quercitrin

[0052] 8 g of precursor i.e., Mimosa-G, Mimosa-C or Cachou and 9.6 g glyoxylic acid were dissolved in 320 mL (g) water under mechanical stirring (~ 30 min) at room temperature (25°C) in a flask. The reaction between the phenolic precursor (hydroxylated) and the aldehyde (crosslinking agent) allows to obtain a phenolic resin. Then, 4.992 g of hexamethylenetetramine, (HMTA) was added into this mixture and stirred for about 5-10 min until complete dissolution. The addition of HMTA as a catalyst causes the formation of a turbid solution of phenolic resin spheres. The mixture is left to stand for an aging time of 48 h. The spheres increase in size and weight and settle on the bottom of the flask. Two phases are observed: a solid phase (composed of polymer spheres) and a liquid phase (composed of the solvent and the rest of the residual organic products).The latter is removed and the solid phase recovered (without centrifugation), by simple pouring for syntheses using mimosa tannins as precursors. For the tannin from catechu, centrifugation was necessary due to the small particle size (< 1µm). The solid phase was dried at 25°C then in an oven at 80°C for approximately 12 hours to evaporate the water and to better crosslink the resin spheres. A pyrolysis step was then carried out in an inert atmosphere (Ar), by heating ~ 7 g of the resin obtained with a heating rate of 5°C / min up to 1500 °C and once the desired temperature is reached a one-hour (1h) plateau is made then a natural cooling step is carried out. The hard carbon is thus obtained (~ 2.6 g) and it is ground manually. The carbons are called MG-00-1500 (from Mimosa-G), MC-00-1500 (from Mimosa-C) or C-00-1500 (from Cachou).For the precursor Mimosa G, two syntheses with a higher amount of glyoxylic acid (14.4 g) were carried out and the obtained polymer pyrolyzed at 1500 and 1600°C (sample names: MG-00-EG-1500 and MG-00-EG-1600). Example 2 Characterization of new carbon materials according to the invention and comparison with known carbon materials 1) Physicochemical characterizations • Adsorption of N2 and CO2

[0053] The textural properties (porosity, specific surface area) of the hard carbons according to the invention were studied by the gas sorption technique with a Micromeritics ASAP 2420 apparatus (Micromeritics France SARL Merignac, France 33700) using nitrogen (N 2 ) as adsorbent at 77K and with a Micromeritics ASAP 2020 using CO 2 as adsorbent at 273K. Before the analysis, the materials were degassed at 300°C for 12h under vacuum on the degassing door to remove water molecules and a second degassing was then carried out for an additional 2h on the analysis door to remove the filling gas. A mass between 150 and 300 mg was used. The BET (Brunauer, Emmett and Teller) specific surface area was calculated in the relative pressure range of 0.05-0.3. • X-ray diffraction (XRD)

[0054] The diffraction data collection is carried out by a Bruker D8 Advance A25 theta / theta geometry diffractometer (goniometer radius: 280mm), with Cu anode. The machine is equipped with a high-resolution ultra-fast 1D LynxEye XE-T detector with energy discrimination (<380eV, Cu Ka1,2). A motorized anti-diffusion knife for efficient suppression of low-angle air scattering is present. The samples are prepared in standard poly(methyl methacrylate) - (PMMA) sample holders by making a powder pyramid which is flattened using a glass slide. The acquisition conditions were as follows: angular range 10-90°2theta, counting step: 0.01°, counting time per step: 0.5s. The total acquisition time amounts to 1h08. During this acquisition, the sample is rotated at 5 rpm. The DIFFRAC.SUITE software, DIFFRAC.EVA ensures the exploitation of the diffractograms and the calculation of the inter-reticular distance d(hkl) (distance between two consecutive planes of the same indices (hkl)) is obtained by simple application of Bragg's law (2d(hkl) sinθ= nλ) where n is an integer (in the case of this work, n=1), λ is the wavelength, and θ the angle of incidence of the X-ray beam on the plane in diffraction conditions of index (hkl). • SEM (scanning electron microscopy)

[0055] The morphology of the carbonaceous material was analyzed with an FEI Quanta 400 Scanning Electron Microscope instrument, high resolution low vacuum field emission gun (FEG). Samples were analyzed with a resolution between 1 mm and 10 µm and a magnification up to 10,000X. ImageJ software was used to determine the average particle size. Multiple images were analyzed and approximately 700 to 1000 particles were counted to produce a particle size distribution histogram. • TPD-MS (temperature programmed desorption coupled with mass spectrometry)

[0056] Programmed thermodesorption coupled to mass spectrometry (TPD-MS) is an analytical method allowing the study of structural changes in the bulk of a material subjected to a controlled temperature variation. More precisely, TPD-MS measures the desorption rate of molecules as a function of temperature, giving valuable information regarding desorption kinetics, surface concentrations, adsorption sites, etc. Regarding carbonaceous materials, TPD-MS is mainly used to identify oxygenated surface functions; functions which, upon decomposition, release CO, CO 2 , H 2 O and H 2 at the specific thermal stability temperature of the corresponding functional group. Thermodesorption measurements were carried out using a homemade setup operating under vacuum, equipped with a mass spectrometer (maximum pressure 10 -4 < Torr).

[0057] Before performing the analyses, the mass spectrometer is calibrated with the following gases: H 2 (m / z=2), H 2 O (m / z=18), CO (m / z=28), N 2 (m / z=28), O 2 (m / z=32) and CO 2 (m / z=44).

[0058] Approximately 15-60 mg HC are placed in a quartz boat and then in an oven and degassed for 12 hours under secondary vacuum to remove the physisorbed water. TPD-MS is performed up to 950°C (with a heating rate of 5°C / min followed by a one-hour hold), and the released gas phase is quantitatively analyzed, throughout the analysis, by the mass spectrometer. • Another important parameter that can be determined by TPD-MS is the active surface area (ASA).

[0059] The active surface of a carbon material corresponds to all the different types of defects present in carbon: stacking faults, single and multiple vacancies, as well as dislocations. The presence of such active sites is important because they can interact with other species (i.e. Li +< , Na +< ). ASA consists of performing oxygen chemisorption followed by a TPD-MS measurement. After a first TPD-MS measurement, the sample under vacuum is brought into contact with oxygen at 300°C (oxygen pressure: 66.5 Pa), which is chemisorbed for 10h, leading to the formation of oxygen complexes on the surface of the material. After these 10 hours, the oxygen is eliminated from the system and a second TPD-MS is carried out (up to 950°C with a heating rate of 10°C / min), and the oxygenated groups formed are decomposed into CO and CO 2 , their quantities then being determined by mass spectrometry.Finally, the ASA value is calculated by taking into account the number of moles of each of the desorbed gases, considering that the surface area of ​​an active site of the carbon material which adsorbs an oxygen atom is 0.083 nm 2< . • Tapped density (packed density)

[0060] This value is measured using a settlement volume meter, such as the STAV II from J. Engelsmann, Ludwigshafen (DE). The procedure is as follows: o Addition of approximately 2g of material to a 10ml graduated cylinder o Measurement of the initial volume (apparent density) o Perform 12,000 strokes (3 cycles of 4,000 strokes) measuring the volume at the end of each cycle (final tapped density at 12,000 strokes).

[0061] To distinguish the new materials from the known ones, the properties of known materials were also studied and measured. These known carbons are as follows: Commercial reference hard carbon PAC2*(AEKYUNG PETROCHEMICAL, K, South Korea) ; Hard carbon PR 600 obtained according to the method described in Maetz et al. Green Chemistry 19 (2017) p.2266; Hard carbon PR 1200 and 1500 described in E. Irisarri et al. (Journal of The Electrochemical Society, 165 (16) A4058-A4066 (2018 )) Hard carbon HC-water obtained according to the method described in Beda et al., Carbon 139 (2018) 248-257, with water as solvent (see Table 1, line 3).

[0062] The results of these measurements are notably compiled in the comparative table below as well as in the figures 2 And 3 . [Table 1] Names TT (°C) d 002 (Å) S BET N 2 (m 2< / g) S BET CO 2 (m 2 < / g) COx (mmol / g) ASA (m 2< / g) Morphology Particle size (µm) ABE1300 1300 3,90 2,7 60,0 0,36 11,9 spheres 3,5 / 7,5 ABE1400 1400 3,88 7,0 20,4 0,11 3,3 spheres 3,9 / 7,5 ABE1500 1500 3,80 3,5 6,4 0,046 1,2 spheres 3,4 / 7,0 ABE1600 1600 3,77 6,1 9,1 0,044 1,3 spheres 3,5 / 7,7 MC-00-1500 1500 3,73 8,5 9.2 0,15 5,8 spheres 2,3 MG-00-1500 1500 3,75 6,0 14,6 0,13 4,3 spheres 4,2 C-00-1500 1500 3,67 11,2 17,4 0,22 6,5 spheres 0,45 MG-00-EG-1500 1500 3,75 6,5 10,5 0,12 4,8 spheres 3,7 MG-00-EG-1600 1600 3,72 6 , 8 13,3- 0,09 3,2 spheres 3,8 PAC2 - 3,75 3,8 3 , 6 0,07 6,4 random 9 HC-water 1300 4,00 72 220 0,21 8,4 random 5 - 200 PR-600 600 4,00 450 - 5,66 - spheres 2-6 PR-1200 1200 3,88 30 394 0,86 24 random 30-200 PR-1500 1500 3,72 58 139 0,64 17 random 30-200 TT - Heat treatment temperature; d 002 - interreticular distance determined by DRX; S BET N 2 and S BET CO2 - BET surface areas determined by N2 and CO2 adsorption; COx - amount of oxygen-based functional groups evaluated by TPD-MS; ASA - active surface area obtained by oxygen chemisorption and TPD-MS; Particle size obtained by the SEM technique.

[0063] The hard carbon according to the invention has a spherical and relatively uniform morphology, which makes it possible to distinguish it from currently available hard carbons. As is clear when comparing the morphologies of a hard carbon according to the invention and a known hard carbon, which are respectively represented in figures 2 And 3 , a hard carbon of known type (Beda et al. and Irisarri et al .) has a heterogeneous and random, non-spherical particle morphology, having very large sizes (up to 200µm). The hard carbon according to the invention not only has a morphology of these particles which is spherical and uniform, but also preferentially a uniformity of size. Finally, this average particle size is advantageously smaller (< 10µm).

[0064] The hard carbon according to the invention is also very different from known spherical amorphous carbons such as PR 600 carbon (Maetz et al .). The hard carbon according to the invention is also a non-porous carbon, that is to say a carbon having a small total pore volume, or a low specific surface area and in particular having a BET N 2 specific surface area of ​​less than 100 m 2 < / g. Another advantageous characteristic is a low quantity of oxygenated functions (COx) on the surface of the material.

[0065] Table 2 below highlights further differences between the hard carbon type according to the invention ABE1300 and the porous carbon PR600. [Table 2] *-measured by XPS : Setting PR600 ABE1300 Surface chemistry composition* Nitrogen-doped carbon (3-4%N, 8%O, 88%C) Carbon without nitrogen (97% C 3% O) Density ** 1.6 g / cm 3< 2.1 g / cm 3<

[0066] X-ray photoelectron spectroscopy (XPS) was performed using a VG SCIENTA SES-2002 spectrometer equipped with a concentric hemispherical analyzer. The incident radiation used was generated by a monochromatic Al Ka ​​(1486.6 eV) X-ray source operating at 420 W (14 kV; 30 mA). The broad scan spectrum signal was recorded with a pass energy of 500 eV.

[0067] **Measured by gas pycnometer: Model: Accupyc 1330 ™< from Micromeritics, under He. Procedure: 20 purges with 5 repetitions on a 1mL cell filled to ¾. Example 3: Effect of the thermopolymerization step

[0068] The use of a thermopolymerization step makes it possible to obtain different distributions in terms of average particle sizes. A carbon material according to the invention was obtained by carrying out a synthesis identical to those of Example 1 having a thermal step at 1300°C but where the thermopolymerization step was replaced by a drying step (or simple polymerization by rest) at 25°C. The results are shown in Figures 4a And 4b And 5a And 5b which show a typical distribution for the material without thermal step ( Fig.5a And b)with two peaks for average size at about 3.5 µm and 6.5 µm and a more complex distribution with two distinct peaks of average particle sizes at 3.5 µm and 7.4 µm. Such a heterogeneous distribution can be advantageous for the porosity of the electrode. The measurement of the particle size of these materials was done using SEM images and ImageJ software which was used to determine the average particle size. Several SEM images were analyzed and about 700 to 1000 particles were counted in order to make a particle size distribution histogram. Example 3bis

[0069] The effect of TEDA vs HMTA catalyst was analyzed using Mimosa-C as precursor, or hydroxylated aromatic compound. The process according to the invention described in Example 1 for Mimosa-C was replicated using either 0.5 g of TEDA or 0.624 g of HMTA. 1 g of precursor i.e., Mimosa-C and 1.2 g glyoxylic acid were dissolved in 40 mL (g) water under mechanical stirring (~ 30 min) at room temperature (25°C) in a flask. Then, TEDA or HMTA were added into this mixture and stirred for about 5-10 min until complete dissolution.

[0070] It was observed that the yield of recovered polymer after the solid / liquid separation phase is substantially improved (from 33% to 82%) when HMTA is used instead of TEDA. Moreover, as shown in figure 16, the morphology obtained in the presence of HMTA is better defined and the particle size is higher. Finally, the use of a higher quantity of HMTA (0.624 g vs. 0.468 g) allows for better uniformity.

[0071] Using the synthesis described in this example with 0.624 g of HMTA, the impact of varying the amount of water and glyoxylic acid as well as the standing time, or maturation, were studied. These data are presented in Tables A, B and C and in figures 17, 18 And 19 . Tableau A Sample MC-00 MC-01 Mimosa-C 1 g 1 g Glyoxylic acid 1.2 g 1.2 g H2O 40 ml 20 ml HMTA 0.624 g 0.624 g Mixing during the maturation phase No No Maturation time 48 h 48 h Polymer mass 0.82 g 1.02 g Morphology Spheres (2.3µm) Spheres (1.8 µm) Carbon efficiency 30% 45 %

[0072] Reducing the amount of water has a beneficial effect on the carbon yield according to the invention. It is also noted that the particle size decreases (cf. Figure 17 ). Tableau B Sample MC-04 MC-00 MC-05 Mimosa-C 1 g 1 g 1 g Glyoxylic acid 0.6 g 1.2 g 1.8g H2O 40 ml 40 ml 40 ml HMTA 0.624 g 0.624 g 0.624g Mixing during the maturation phase No No No Maturation time 48 h 48 h 48 h Polymer mass - 0.8201 g 0.9809 Morphology Spheres (1.5µm) Spheres (2.3 µm) Spheres (1.9 µm) Carbon efficiency 34% 30% 43%

[0073] A decrease in the amount of glyoxylic acid appears to reduce the particle size (cf. Fig. 18 ). Tableau C Sample MC-0524 MC-05 MC-0572 MC-0597 Precursor Mimosa-C Mimosa-C Mimosa- C Mimosa-C Mass 1 g 1 g 1 g 1 g Glyoxylic acid 1.8g 1.8g 1.8g 1.8g H2O 40 ml 40 ml 40 ml 40 ml HMTA 0.624g 0.624g 0.624g 0.624g Blend No No No No Maturation time 24 h 48 h 72 h 97 h Morphology Spheres (1.8µm) Spheres (1.9 µm) Spheres (2.4 µm) Spheres (2.2 µm) Carbon efficiency 26.0% 44.0% 47.0% 51.0%

[0074] The resting time appears to be optimized at around 48 hours because an increase in this duration only allows a small increase in the size of the spheres (cf. Fig. 19 ). Example 4: Examples of electrochemical devices according to the invention and comparative data with a prior art material (PAC2)

[0075] Button-type electrochemical cells were assembled according to the scheme of the Figure 6 .

[0076] Electrodes according to the invention are manufactured by mixing: 94% by mass of a hard carbon according to the invention ABE 1300, ABE 1400, ABE 1500 and ABE 1600; 3% by mass of carbon black as a conductive additive (C45 from Imerys, Paris, FR); and 3% by mass of poly(vinylidene fluoride) (PVDF), PVDF 5130 or SOLEF from SOLVAY, as a polymer binder; in the mortar for 5 minutes.

[0077] ≈1 g of dispersed powder is placed in a bottle with a magnetic bar. ≈1 g of solvent N-methyl-2-pyrrolidone (NMP) (CAS No. 872-50-4) is added and the mixture is dispersed for 12 hours at 300 rpm at 25°C. The liquid, or ink, thus obtained is deposited by coating on an aluminum collector (from RJC HOLDINGS CORPORATION in Incheon-City, South Korea). The ink layer is dried for 2 hours at 60°C under air flow. The films thus obtained have a thickness between 130µm and 160µm (collector included) and a mass varying between 7.5-1 0.2 mg / cm 2 < of active material. The films are then calendered by successive passage between 2 rollers separated by an increasingly smaller magnitude until a film is obtained whose thickness remains unchanged regardless of the pressure applied to the film. The films are then pelletized to obtain circular electrodes of 1 cm 2< for the batteries cycling vs Na and 1.327 cm 2< for those cycling vs NVPF. The electrodes are then dried in an oven at 70°C for 2 hours as well as the different parts of the button cell assembly.

[0078] For full cell devices, NVPF electrodes are obtained by mixing: 92% by mass of NVPF produced by LRCS in Amiens 4% by mass of carbon black as a conductive additive (C45 from Imerys, Paris, FR); and 4% by mass of poly(vinylidene fluoride) (PVDF), PVDF 5130 or SOLEF from SOLVAY, as a polymer binder; in the mortar for 5 minutes.

[0079] ≈1 g of dispersed powder is placed in a bottle with a magnetic bar. ≈1 g of N-methyl-2-pyrrolidone (NMP) (CAS No. 872-50-4) is added and the mixture is dispersed for 12 hours at 300 rpm at 25°C. The liquid, or ink, thus obtained is deposited by coating on a 22µm aluminum collector (from RJC HOLDINGS CORPORATION in Incheon-City, South Korea). The ink layer is dried for 2 hours at 60°C under air flow. The films thus obtained have a thickness between 140µm and 200µm (collector included) and a mass varying between 15-20mg / cm 2 < of active material.

[0080] The films are then calendered by successive passage between 2 rollers separated by an increasingly smaller size until a film is obtained whose thickness remains unchanged regardless of the pressure applied to the film. The films are pelletized to obtain circular electrodes of 1.327cm 2 < . The electrodes are then dried in an oven at 70 ° C for 2 hours as well as the different parts of the button cell assembly. The electrodes comprising ABE 1400, 1500 and 1600 material were associated with sodium metal (to constitute a half-element or half-cell configuration). The electrode comprising ABE 1300 material was associated with an electrode based on Sodium vanadium (III) fluorophosphate (NVPF), to constitute a configuration in a complete cell, "full cell").

[0081] The elements of the half-element device are shown in Figure 6. Except for the electrodes, they come from the company INNOV' METOR, FERRIERES EN GATINAIS, FR. A stainless steel spring 6 is positioned in a lower part 2 of a steel cover and inside an insulating ring 4. A current collector 8 made of 316L stainless steel and 0.5 mm thick is positioned on the circular spring. This collector 8 is a disk with a diameter of approximately 15 mm covered with sodium metal. Sodium metal was spread over the entire upper surface of the collector 8 and then scraped with a spatula to obtain a clean surface, without metal oxides. A separator disk 10 made of glass fibers, 1 mm thick and 16 mm in diameter, is positioned on the sodium metal surface. 200 µL of electrolyte is then added. This electrolyte is a mixture of ethyl carbonate (EC) and dimethyl carbonate (DMC) in proportions (1:1% mass-mixture to which the salt NaPF 6 is added in proportions of 1 mol / L.Then a hard carbon electrode 12 as described above is positioned on the separator 10. Finally the upper part 14 of the stainless steel cover is positioned to encapsulate the electrode 12 and the two parts of the cover 2 and 14 are secured together (for example crimped). In this device the electrode 12 is in the cathode position and the sodium metal is the anode. The production of this device is carried out under argon in a glove box. The electrochemical cell is left to rest for 2 hours before the first cycle. The characteristics of the device are then measured by galvanostatic cycling at C / 50 in discharge and charge with a rest of 1 minute between 2 modes. Two half-cells (CELL 1 and CELL 2) were studied and as shown by the results in . Figures 8 to 10, the curves obtained are identical. The acquisition of the specific capacitance values ​​was carried out when the variation of the potential reached 10mV compared to the previous acquisition and / or every 5 seconds. In this way it is possible to know the specific capacitance precisely.

[0082] The elements of the device in a complete cell are represented in the Figure 7. With the exception of the electrodes, they come from the company INNOV' METOR, FERRIERES EN GATINAIS, FR. A stainless steel spring 106 is positioned in a lower part 102 of a steel cover and inside an insulating ring 104. A current collector 108 made of 316L stainless steel and 0.5 mm thick is positioned on the circular spring. This collector 108 is a disc with a diameter of approximately 15 mm on which is positioned an electrode 112 comprising a material according to the invention ABE 1300. The electrode 112 adopts the form of a disc with a diameter of 1.3 cm and a thickness of approximately 110 µm (collector included). A separator disc 110 made of glass fibers, 1 mm thick and 16 mm in diameter, is positioned on the electrode 112. 200 µL of electrolyte is then added. This electrolyte is a mixture of ethyl carbonate (EC) and dimethyl carbonate (DMC) in proportions (1:1% by mass), to which NaPF6 is added in proportions of 1 mol / L.Then an NVPF electrode 109 with a diameter of 1.3 cm as described above is positioned on the separator 110. Finally, the upper part 114 of the stainless steel cover is positioned to encapsulate the electrodes 112 and 109 and the two parts of the cover 102 and 114 are secured together (for example crimped). In this device, the electrode 112 constitutes the anode and the electrode 109 the cathode. The production of this device is carried out under argon in a glove box. The electrochemical cell is left to rest for 2 hours before the first cycle. The mass ratio between the mass of NVPF and the ABE 1300 material, NVPF / ABE1300, varies between 2 and 2.5.

[0083] The variation of the specific capacitance as a function of voltage is represented in Figures 12 and 13 and was measured as follows: Retention cycling:

[0084] Training: galvanostatic cycling over 5 cycles at C / 5 & D / 5 at 25°C with a 5-minute rest. Retention: galvanostatic cycling at 1C & 1D at 25°C with a 5-minute rest.

[0085] The specific capacities of the cell were measured as follows: The specific capacities as a function of the applied regime (at different currents) make it possible to obtain important information on the performance of the cells in power, for example with a view to addressing certain industrial applications represented in Figures 14 and 15 . Power cycling:

[0086] Training: Galvanostatic cycling over 5 cycles at C / 5 & D / 5 at 25°C with a 5-minute rest Crate: Galvanostatic cycling at variable charge over 5 cycles: from C / 5 to 4C and at constant discharge: D / 5 at 25°C with a 5-minute rest Drate: Galvanostatic cycling at constant charge: C / 5 & at variable charge over 5 cycles: from D / 5 to 4D at 25°C with a 5-minute rest

[0087] The specific capacity of the cell is high (approximately 125 mAh*g -1< ). The specific discharge capacity corresponds to 80% of the charge capacity which corresponds to an initial irreversible capacity of 25 mAh g -1< , when cycled at a C / 5 rate. This capacity loss is due to the irreversibility of the electrode with the highest irreversibility, i.e., hard carbon (irreversibility of NVPF: 10%). The capacity decreases to -75 mAh g-1 when cycled at 1C / 1D. When evaluating the regime (current variation) on the capacity, it was found that the cycling rate used during the charge / discharge step (insertion / extraction of Na+ into / from the hard carbon anode) is critical to ensure good efficiency. If a sufficiently low current is used to charge the cell, even high discharge rates (3D) eventually give good performance (-80% capacity retention).On the contrary, when a fast charge rate is used (i.e. 1C), low efficiency is obtained even if the applied discharge current is low (i.e. D / 5).

[0088] Porosity, COx functional groups and structural defects quantified by ASA have a significant influence on the initial irreversible capacity. The irreversible capacity decreases with the decrease in structural defects (ASA) and with the decrease in COx groups. In addition, the irreversible capacity decreases with the increase in tapped density.

[0089] Table 3 below compiles characteristics of carbon materials according to the invention and those of the cells comprising them as well as the characteristics of a prior art material PAC2 and of a cell comprising it as described above. [Table 3] Carbon material Density He (g / cm 3< ) Packed density g / cm 3< ) Porosity after pelletizing (%) Circumference (%) Q iD (mAh g -1< ) Q iC (mAh g -1< ) PAC2* 1,954 0,96 46 14 323 278 ABE1300 2,107 0,71 62 11 341 303 ABE1400 2,163 0,74 54 11 346 307 ABE1500 1,875 0,84 46 8 320 294 ABE1600 1,633 0,72 41 8 337 309 MC-00-1500 2,10 0,73 58 15 374 315 MG-00-1500 2,05 0,73 56 15 385 329 C-00-1500 1,97 0,71 58 18 354 286 MG-00-EG-1500 2,12 0,67 64 17 403 334 MG-00-EG-1600 1,85 0,70 49 13 366 317 PR1200 / 0,7 / / / / PR1500 / 0,7 / / / / Cirrev = irreversible capacity; Q iD = initial discharge capacity, Q iC = initial charge capacity.

[0090] The materials according to the invention have a significant advantage in terms of initial irreversible capacity, which is lower compared to other similar hard carbon materials.

Claims

1. Carbon material comprising particles of hard, non-porous carbon having a spherical morphology, this material having an interlayer distance d002 greater than 3.6 Å, a total specific surface area, measured by the BET N2 method, of less than 75 m2 / g and a total specific surface area, measured by the BET CO2 method, of 1 to 100 m2 / g, preferably of 1 to 60 m2 / g.

2. Carbon material according to claim 1, wherein the interlayer distance is between 3.70 Å and 4.00 Å, advantageously is chosen from a range of 3.75 Å to 3.90 Å, and even more preferentially from a range of 3.70 Å to 3.80 Å.

3. Carbon material according to claim 1 or 2, wherein said total specific surface area, measured by the BET N2 method, is from 1 to 50 m2 / g, in particular from 1 to 10 m2 / g, and even more preferably from 1 to 3.5 m2 / g.

4. Carbon material according to one of claims 1 to 3, wherein said total specific surface area, measured by the BET CO2 method, is from 1 to 21 m2 / g, in particular from 1 to 10 m2 / g.

5. Carbon material according to one of claims 1 to 4, wherein said material has a tapped density greater than 0.7 g / cm3, for example chosen from the range of 0.72 g / cm3 to 1.1 g / cm3, preferably greater than 0.84 g / cm3.

6. Carbon material according to one of claims 1 to 5, said material having an active surface area (ASA) of less than 12 m2 / g, and more preferably less than 5 m2 / g.

7. Carbon material according to one of claims 1 to 6, said material having an oxygen-based functional group content of less than 0.5 mmol / g, preferably less than 0.1 mmol / g, in particular less than 0.05 mmol / g.

8. Carbon material according to one of claims 1 to 6, wherein the particles have a size between 0 µm and 15 µm, preferably between 0 µm and 10 µm.

9. Method for manufacturing a non-porous carbon material comprising at least the following steps: a) a step of mixing, in the presence of a polar protic solvent, at least: - an amine catalyst selected from the group consisting of triethylenediamine (TEDA), quinuclidine, triethylamine (TEA), hexamethylenetetramine (HMTA) and mixtures thereof; - an aromatic hydroxyl compound chosen in particular from the group consisting of phenol, resorcinol and phloroglucinol, catechin, pyrogallol, hydroxyquinol, gallic acid, polyphenols, such as tannins, and mixtures thereof; - an aldehyde compound, selected from the group consisting of glyoxal, formaldehyde, acetaldehyde, a keto acid, glyoxylic acid, pyruvic acid, 2-methyl-3-oxopropanoic acid, and mixtures thereof; b) a step of maturation of the mixture obtained at the end of step a), preferably at a temperature comprised between 20 and 35°C, for example for a period comprised between 0.5 and 5 days, making it possible to obtain a solid phase comprising spheres of phenolic resin and a liquid phase; c) a step of controlled separation of said solid phase from said liquid phase; d) a step of polymerization and / or drying of said solid phase for a period of 1 to 48 hours resulting in the formation of a dry phenolic resin; e) a step of carbonizing said dry phenolic resin, preferably in the presence of a flow of inert gas at a temperature between 1200°C and 2000°C to obtain a non-porous carbon material; and f) optionally a step of recovering the carbon material.

10. Method according to claim 9, wherein the polymerization step is a thermal step, preferably by heating to a temperature of 70°C to 150°C.

11. Method according to claim 10, wherein the amine catalyst is triethylenediamine, the aromatic hydroxyl compound is preferably phloroglucinol or a condensed tannin; and wherein the aldehyde compound is preferably glyoxylic acid.

12. Method according to one of claims 9 to 11, wherein the maturation step b) is carried out in the absence of stirring.

13. Method according to one of claims 9 to 12, wherein the separation step c) is carried out without centrifugation.

14. Electrode comprising a carbon material as described in one of claims 1 to 8.

15. Use of a carbon material as described in any one of claims 1 to 8 for the manufacture of an electrode or an electrode material.

16. Use of a carbon material according to claim 15, wherein said electrode is an electrode for rechargeable batteries, in particular for sodium-ion, lithium-ion, potassium-ion or Li-S batteries.