Method for manufacturing a porous anode, porous anode obtained thereby, lithium-ion battery comprising this anode, method for manufacturing a battery, and use of lithium-ion battery

Abstract

A method for manufacturing an anode with a porosity between 25% and 50% by volume, wherein (a) a substrate is provided and a colloidal suspension or paste in aggregate or dispersion form composed of monodisperse primary nanoparticles of at least one anode active material A, wherein the active material A of the anode is selected from niobium oxide and mixed oxides of niobium with titanium, germanium, cerium, lanthanum, copper or tungsten, and the average diameter D50 of the monodisperse primary nanoparticles is between 2 nm and 100 nm; (b) a layer of the colloidal suspension or paste provided in step (a) is deposited on at least one surface of the substrate by a method selected from the group consisting of: electrophoresis, extrusion, printing and coating methods; and (c) the layer obtained in step (b) is dried and solidified by pressure and / or heating to obtain a porous layer.

Description

Technical Field

[0001] This invention relates to the field of electrochemistry, and more particularly to electrochemical systems. Specifically, it relates to electrodes used in batteries. This invention relates to a novel method for manufacturing porous anodes that can be used in electrochemical systems such as high-power batteries (especially lithium-ion batteries). This method utilizes nanoparticles of the anode material.

[0002] This invention also relates to an anode obtained by this method, which is mesoporous. This invention also relates to a battery comprising such a porous anode. In this respect, this invention also relates to a method for preparing a lithium-ion battery formed from such a mesoporous anode, wherein the mesoporous anode is in contact with a porous separator, which in turn is in contact with a porous cathode. These porous electrode / septum assembly can be immersed in a liquid electrolyte.

[0003] More precisely, the present invention relates to an anode that combines the following features: high volumetric capacity (expressed in milliamperes per cubic centimeter (mAh / cm³), sufficiently high insertion potential to allow for rapid recharging without any risk of lithium plating, and no significant volume change during charging and discharging, thereby enabling the battery to be used in a rigid, monolithic solid-state and mesoporous form. Prior Technology

[0004] Ideally, batteries used to power automated electrical devices (such as telephones and laptops, handheld tools, and automatic sensors) or to drive electric vehicles should have a long lifespan, be able to store large amounts of energy and power, function over a very wide temperature range, and not be at risk of overheating or explosion.

[0005] Currently, these electrical devices are primarily powered by lithium-ion batteries, which offer the best energy density among various storage technologies. Different electrode structures and chemical compositions are available to manufacture lithium-ion batteries. Methods for manufacturing lithium-ion batteries are documented in numerous patent documents and are well-documented in "Advances in Lithium-Ion Batteries" (Ed. W. van Schalkwijk and B. Scrosati) (Kluever Academic / Plenum Publishers) published in 2002, and "Lithium Batteries. Science and Technology" (C. Julien, A. Mauger, A. Vijh, and K. Zaghib) (Springer, Heidelberg 2016).

[0006] The electrodes of lithium-ion batteries can be manufactured using known coating techniques, especially techniques such as roll coating, curtain coating, slot coating, doctor blade coating, and tape casting.

[0007] In these methods, the active material used to manufacture the electrode is used in the form of a powder suspension with an average particle size between 5 micrometers (µm) and 15 µm. These particles are integrated into an ink, which consists of these particles, an organic binder, and a filler (conductive filler, typically carbon black) made of conductive material powder. This ink is deposited on the surface of a metal substrate and then dried to remove the organic solvents it contains, leaving only a porous deposit on the surface of the metal strip, consisting of particles of active material mechanically bonded together by an organic binder and electrically linked by carbon black.

[0008] These techniques can produce layers with thicknesses ranging from approximately 20 µm to approximately 400 µm. Depending on the layer thickness, porosity, and the size of the active particles within it, the power and energy of the battery can be adjusted.

[0009] According to prior art, the ink (or paste) deposited to form the electrode contains particles of active material, as well as (organic) binders, toner to ensure electrical contact between the particles, and solvents that evaporate during the electrode drying step. To improve the quality of the electrical contact between the particles and to compact the deposited layer, a calendering step is performed on the electrode. After this calendering step, the active particles of the electrode occupy approximately 60-70% of the deposit volume, meaning that approximately 30-40% porosity is typically left between the particles.

[0010] To optimize the volumetric energy density of lithium-ion batteries manufactured using these conventional methods, reducing the porosity of the electrodes is a useful approach. Reducing porosity, in other words, increasing the amount of active material per unit volume of the electrode, can be achieved in various ways.

[0011] In extreme cases, vacuum deposition techniques, such as physical vapor deposition (PVD), are used to fabricate electrode films with the highest energy density per unit volume. These films are completely dense and non-porous. However, because these completely solid films do not contain liquid electrolytes to aid ion transport or electronic conduction charges to aid charge transport, their thickness is limited to a few micrometers to prevent excessive resistance.

[0012] Using standard inking techniques, volumetric energy density can also be increased by optimizing the size distribution of the deposited particles. In fact, as shown in the article "Effect of particle size distribution on sintering of agglomerate-free submicron alumina powder compacts" by J. Ma and LC Lim, published in review J. European Ceramic Society 22 (2002), pp. 2197-2208, optimization of particle size distribution can achieve a density of approximately 70%. An electrode with 30% porosity, containing conductive charges, and impregnated with a lithium-ion conductive electrolyte will have a volumetric energy density approximately 35% higher than the same electrode with 50% porosity and composed of monodisperse particles.

[0013] Furthermore, due to the impregnation in a highly ion-conducting phase and the addition of electronic conductors, the thickness of these electrodes can be significantly increased compared to those achievable using vacuum deposition techniques. This increased thickness also contributes to increasing the energy density of the battery cell.

[0014] While this increases the energy density of the electrode, the size distribution of the active material particles is not without its problems. Particles of different sizes in the electrode have different capacities, and under the same charging and / or discharging current, they will be more or less locally charged and / or discharged depending on their size. When the battery is no longer under current load, the local charge states between the particles will rebalance, but during these transition phases, local imbalances may cause the local load of the particles to exceed their stable voltage range. The higher the current density, the more pronounced these local charge state imbalances become. These imbalances can therefore lead to a loss of cycle performance, safety risks, and limitations on the power of the battery cell.

[0015] The effect of active material particle size distribution on electrode current / voltage relationship has been studied and simulated in the publication "A study on the effect of porosity and particles size distribution on Li-ion battery performance" by ST Taleghani et al., published in J. Electrochemical Society, 164 (11) 2017, p. E3179-E3189.

[0016] In prior art electrode ink technology, the particle size of the active material is typically between 5 µm and 15 µm. The contact between two adjacent particles is essentially a point contact, with the particles bonded together by an organic binder, which is in most cases PVDF.

[0017] The liquid electrolyte used for impregnating the electrodes consists of an aprotic solvent in which lithium salts are dissolved. These organic electrolytes are highly flammable and can cause violent combustion of the battery cell, especially when the active cathode material is subjected to a voltage range exceeding its stable voltage range, or when hot spots appear locally in the battery.

[0018] To address the inherent safety issues in the structure of traditional lithium-ion batteries, the following operations must be performed.

[0019] High-temperature stable ionic liquids are used to replace organic solvent-based electrolytes. However, ionic liquids do not wet the surface of organic materials, and the presence of PVDF and other organic binders in conventional battery electrodes prevents the electrodes from being wetted by this type of electrolyte, affecting battery performance. Ceramic separators have been developed to address this problem at the electrolyte interface between electrodes, but the presence of organic binders in the electrodes continues to pose challenges to the utilization of ionic liquid electrolytes.

[0020] To achieve uniform particle size, localized charge imbalances are necessary. These imbalances can cause localized stress on the active material during intense discharge, exceeding its conventional operating voltage. This optimization can negatively impact the battery's energy density.

[0021] To ensure a uniform distribution of conductive charge (carbon black) in the electrodes, it is important to avoid areas with high resistance, which can lead to hot spots during battery operation.

[0022] More specifically, regarding methods for manufacturing battery electrodes according to prior art, the manufacturing cost depends in part on the properties of the solvents used. Aside from the inherent cost of the active materials, the cost of manufacturing the electrodes largely depends on the complexity of the inks (binders, solvents, carbon black, etc.) used.

[0023] NMP is the primary solvent used in the manufacture of lithium-ion battery electrodes. NMP is also an excellent solvent for PVDF, which is dissolved in inks as a binder. Drying the NMP contained in the electrode is a significant economic issue. NMP's high boiling point and very low vapor pressure make it difficult to dry. The solvent vapor must be collected and reprocessed. Furthermore, to ensure better adhesion between the electrode and the substrate, the drying temperature of NMP should not be too high, as this would further increase drying time and cost. These points are described in the publication "Technical and economic analysis of solvent-based lithium-ion electrode drying with water and NMP" by DL Wood et al., published in Drying Technology, vol. 36, n 2 (2018).

[0024] Other cheaper solvents, especially water and ethanol, can be used to manufacture inks. However, their surface tension is greater than that of NMP, resulting in lower efficiency in wetting the surface of metal current collectors. Furthermore, particles, especially carbon black nanoparticles, tend to agglomerate in water. This agglomeration leads to uneven distribution of the components entering the electrode (binder, carbon black, etc.). Additionally, even after drying, small amounts of water remain adsorbed on the surface of the active material particles in water or ethanol.

[0025] Finally, besides the issue of preparing inks to achieve high-efficiency, low-cost electrodes, it is also important to remember that the ratio between energy density and power density can be adjusted depending on the particle size of the active material, and indirectly on the porosity and thickness of the electrode deposit. J. Newman's article "Optimization of Porosity and Thickness of a Battery Electrode by Means of a Reaction-zone Model," published in review J. Electrochem. Soc., Vol. 142, n 1 (1995), reveals the respective effects of electrode thickness and porosity on its discharge power and energy density.

[0026] Besides the structure and manufacturing method of the battery cell, the selection of electrode materials is also fundamental. The energy stored in the battery is the product of the battery capacity (ampere-hours (Ah) or milliampere-hours (mAh)) and the battery's operating voltage. This operating voltage is the difference between the lithium insertion potentials at the anode and cathode.

[0027] The lower the lithium insertion potential of the anode, the higher the energy output of a battery with the same isocapacity. However, anodes with low insertion potentials, such as graphite, are at risk of lithium plating at high charging currents. In fact, to charge the battery quickly, a large amount of lithium needs to be rapidly inserted into the anode. The high concentration of lithium on the anode surface, associated with a very low potential, promotes the precipitation of lithium dendrites, which can cause short circuits in the battery.

[0028] In addition, if you want to obtain a battery with very fast charging capacity, no safety issues caused by lithium deposition, and high energy density, the following operations must be performed simultaneously.

[0029] Anodes that insert lithium at a relatively high potential (above 0.5 V / Li) are used to avoid the formation of lithium dendrites during the fast charging phase. These anodes must also have high mass capacity to compensate for energy loss by reducing the operating voltage through increased capacitance.

[0030] Electrodes with a very large specific surface area and as uniform a particle size (thickness of the insertion region) as possible are used to avoid dynamic imbalance.

[0031] It has electrodes with excellent ionic and electronic conductivity.

[0032] It possesses an electrolyte with good ion conductivity, high transport quantity, and low polarization resistance.

[0033] The present invention aims to provide a lithium-ion battery having at least some of these technical features, preferably all of them. According to the present invention, the above-mentioned problems can be solved by the prudent selection of the anode structure and its materials, and by a method for manufacturing an anode having such a structure. Summary of the Invention

[0034] According to the present invention, the above-mentioned problems are solved by a method for manufacturing a porous anode for a battery, which is one of the first objectives of the present invention, wherein the battery includes an anode, a separator and a cathode, and the anode has a porosity of between 25% and 50% by volume (preferably about 35%) and pores with an average diameter of less than 50 nanometers (nm).

[0035] The method for manufacturing a porous anode for a battery according to the present invention includes the following steps.

[0036] (a) A substrate and a colloidal suspension or paste in aggregate or dispersion form, consisting of monodisperse primary nanoparticles of at least one anode active material A, wherein the average diameter D50 of the monodisperse primary nanoparticles is between 2 nm and 100 nm, preferably between 2 nm and 60 nm, the colloidal suspension or paste also comprising a liquid component, and the anode active material A is selected from niobium oxides and mixed oxides of niobium with titanium, germanium, cerium, lanthanum, copper or tungsten, preferably selected from the group consisting of: Nb 2O 5-δ, Nb 18W 16O 93-δ, Nb 16W 5O 55-δ, 0 ≤ x < 1 and 0 ≤ δ ≤ 2; TiNb₂O₇ ... Ti 1-xM 1 xNb 2-yM 2 yO 7-zM 3 z, Li wTi 1-xM 1 xNb 2-yM 2 yO 7, where M1 and M2 are each selected from at least one element chosen from the group consisting of Nb, V, Ta, Fe, Co, Ti, Bi, Sb, As, P, Cr, Mo, W, B, Na, Mg, Ca, Ba, Pb, Al, Zr, Si, Sr, K, Cs, Ce, and Sn. M1 and M2 may be the same or different from each other. M3 is at least one halogen, wherein 0 ≤ w ≤ 5, 0 ≤ x ≤ 1, 0 ≤ y ≤ 2, and z ≤ 0.3; TiNb2O7-zM3z, LiwTiNb2O7-zM3z, wherein M3 is at least one halogen, preferably selected from F, Cl, Br, I, or mixtures thereof, and 0 ≤ w ≤ 5 and 0 < z ≤ 0.3; 1-xGe z. Ti 1-xCu z, among which M1 and M2 are each selected from at least one element chosen from the group consisting of Nb, V, Ta, Fe, Co, Ti, Bi, Sb, As, P, Cr, Mo, W, B, Na, Mg, Ca, Ba, Pb, Al, Zr, Si, Sr, K, Cs, Ce, and Sn; M1 and M2 may be the same or different from each other, wherein 0 ≤ w ≤ 5, 0 ≤ x ≤ 1, 0 ≤ y ≤ 2, and z ≤ 0.3; Ti 1-xGe xNb 2-yM 1 yO 7-z, Li wTi 1-xGe xNb 2-yM 1 yO 7-z, Ti 1-xCe xNb 2-yM 1 yO 7-z, Li wTi 1-xCe xNb 2-yM 1 yO 7-z, where M1 is selected from at least one element of the group consisting of Nb, V, Ta, Fe, Co, Ti, Bi, Sb, As, P, Cr, Mo, W, B, Na, Mg, Ca, Ba, Pb, Al, Zr, Si, Sr, K, Cs, Ce and Sn, wherein 0 ≤ w ≤ 5, 0 ≤ x ≤ 1, 0 ≤ y ≤ 2 and z < 1, preferably 0 ≤ w ≤ 5, 0 ≤ x ≤ 1, 0 ≤ y ≤ 2 and z < 0.3.

[0037] (b) Depositing a layer of the colloidal suspension or paste provided in step (a) on at least one side of the substrate by means of a method selected from the group consisting of: electrophoresis, extrusion, printing methods (preferably inkjet printing or flexographic printing) and coating methods (preferably blade coating, roller coating, curtain coating, dip coating or slit extrusion coating).

[0038] (c) Dry the layer obtained in step (b) and solidify it by applying pressure and / or heating to obtain a porous layer.

[0039] Advantageously, the active material A of the anode can also be selected from niobium oxides and mixed oxides of niobium with titanium, germanium, cerium, lanthanum, copper or tungsten, and is preferably selected from the group consisting of: Nb 2O 5-δ, Nb 18W 16O 93-δ, Nb 16W 5O 55-δ, 0 ≤ x < 1 and 0 ≤ δ ≤ 2; The following are possible combinations of elements: TiNb₂O₇ ... Ti 1-xM 1 xNb 2-yM 2 yO 7-zM 3 z, Li wTi 1-xM 1 xNb 2-yM 2 yO 7-zM 3 z, where M1 and M2 are each selected from at least one element chosen from the group consisting of Nb, V, Ta, Fe, Co, Ti, Bi, Sb, As, P, Cr, Mo, W, B, Na, Mg, Ca, Ba, Pb, Al, Zr, Si, Sr, K, Cs, Ce, and Sn. M1 and M2 may be the same or different from each other. M3 is at least one halogen, wherein 0 ≤ w ≤ 5, 0 ≤ x ≤ 1, 0 ≤ y ≤ 2, and z ≤ 0.3; TiNb2O7-zM3z, LiwTiNb2O7-zM3z, wherein M3 is at least one halogen, preferably selected from F, Cl, Br, I, or mixtures thereof, and 0 ≤ w ≤ 5 and 0 < z ≤ 0.3; 1-xGe z. Ti 1-xCu z, among which M1 and M2 are each selected from at least one element chosen from the group consisting of Nb, V, Ta, Fe, Co, Ti, Bi, Sb, As, P, Cr, Mo, W, B, Na, Mg, Ca, Ba, Pb, Al, Zr, Si, Sr, K, Cs, Ce, and Sn; M1 and M2 may be the same or different from each other, wherein 0 ≤ w ≤ 5, 0 ≤ x ≤ 1, 0 ≤ y ≤ 2, and z ≤ 0.3; Ti 1-xGe xNb 2-yM 1 yO 7-z, Li wTi 1-xGe xNb 2-yM 1 yO 7-z, Ti 1-xCe xNb 2-yM 1 yO 7-z, Li wTi 1-xCe xNb 2-yM 1 yO 7-z, where M1 is selected from at least one element of the group consisting of Nb, V, Ta, Fe, Co, Ti, Bi, Sb, As, P, Cr, Mo, W, B, Na, Mg, Ca, Ba, Pb, Al, Zr, Si, Sr, K, Cs, Ce and Sn, wherein 0 ≤ w ≤ 5, 0 ≤ x ≤ 1, 0 ≤ y ≤ 2 and z < 1, preferably 0 ≤ w ≤ 5, 0 ≤ x ≤ 1, 0 ≤ y ≤ 2 and z < 0.3.

[0040] Alternatively, in step (c), the layer is heated to a sufficiently high temperature by evaporation and / or pyrolysis to remove organic residues (referred to as the debinding step).

[0041] More typically, the heat treatment in step (c) is carried out in multiple steps or with a continuous temperature ramp. This process begins with drying, followed by optional degreasing (which is a heat treatment in air used for pyrolyzing or calcining the organic material) if the deposit contains organic material, and finally a consolidation process, which may consist of only heat treatment and / or thermomechanical treatment.

[0042] The active material A of the anode is represented by chemical formulas indicating the possible presence of lithium, namely LiwTi1-xM1xNb2-yM2yO7, LiwTi1-xM1xNb2-yM2yO7, LiwTi1-xGexNb2-yM1yO7-zM2, LiwTi1-xGexNb2-yM1yO7-z, LiwTi1-xLaxNb2-yM1yO7-zM2, LiwTi1-xCuxNb2-yM1yO7-zM2, LiwTi1-xCexNb2-yM1yO7-zM2, and LiwTi1-xCexNb2-yM1yO7-zM2. 7-z, with w = 0 (i.e. lithium-free) supply and deposition of active material A at the anode, which is capable of inserting lithium during the first charge of the battery, where the anode is formed as part of the battery.

[0043] In step (b), deposition can be performed on both sides of the substrate.

[0044] In the first embodiment, the substrate may be a substrate capable of serving as a current collector. After step (c), the thickness of the layer is advantageously between about 1 µm and about 300 µm, or between 1 µm and 150 µm.

[0045] In the second embodiment, the substrate is a temporary intermediate substrate, such as a polymer film. In this second embodiment, the layer can be separated from the substrate after drying, preferably before heating, but no later than the end of step (c). After step (c), the thickness of the layer is advantageously between about 5 µm and about 300 µm.

[0046] In both embodiments, if the layer is thick and has high resistance, then adding step (d) is advantageous.

[0047] (d) Deposition of conductive material coating, i.e., formation on and in the pores of the porous layer, wherein the conductive material is preferably carbon or conductive oxide material.

[0048] Step (d) can be performed using atomic layer deposition (ALD) technology.

[0049] Step (d) may include the following consecutive steps, wherein in step (d1) a layer of conductive material precursor is deposited on and within the pores of the porous layer, and in step (d2) the conductive material precursor deposited on the porous layer is transformed into conductive material, so that the porous layer has a layer of conductive material on and within the pores.

[0050] The conductive material can be carbon. In this case, step (d1) is advantageously carried out by immersing the porous layer in a liquid phase containing a carbon-rich compound (e.g., sugars); the transformation of the conductive material in step (d2) is carried out by pyrolysis, preferably in an inert environment, and more preferably in nitrogen.

[0051] Step (d1) is advantageously carried out by immersing the porous layer in a liquid phase containing a precursor of conductive material, and in this case, the conversion of the precursor of conductive material in step (d2) into conductive material is carried out by heat treatment, such as calcination, preferably in an air or oxidizing environment.

[0052] Advantageously, the precursor of the conductive material is selected from organic salts containing one or more metal elements capable of forming conductive oxides after heat treatment, preferably in air or an oxidizing environment, such as calcination. These metal elements, preferably metal cations, may advantageously be selected from tin, zinc, indium, gallium, or mixtures of two, three, or four of these elements. The organic salt is preferably selected from alkoxides of at least one metal element capable of forming conductive oxides after heat treatment, preferably in air or an oxidizing environment, such as calcination; oxalates of at least one metal element capable of forming conductive oxides after calcination in air; and acetates of at least one metal element capable of forming conductive oxides after heat treatment, preferably in air or an oxidizing environment, such as calcination.

[0053] Advantageously, the conductive material can be a conductive oxide material, preferably selected from: Tin oxide (SnO 2), zinc oxide (ZnO), indium oxide (In 2O 3), gallium oxide (Ga 2O 3), mixtures of two of these oxides (e.g., indium tin oxide, corresponding to a mixture of indium oxide (In 2O 3) and tin oxide (SnO 2), mixtures of three of these oxides, or mixtures of four of these oxides. The zinc oxide-based doped oxide is preferably doped with gallium (Ga) and / or aluminum (Al) and / or boron (B) and / or beryllium (Be) and / or chromium (Cr) and / or cerium (Ce) and / or titanium (Ti) and / or indium (In) and / or cobalt (Co) and / or nickel (Ni) and / or copper (Cu) and / or manganese (Mn) and / or germanium (Ge). The indium oxide-based doped oxide is preferably doped with tin (Sn) and / or gallium (Ga) and / or chromium (Cr) and / or cerium (Ce) and / or titanium (Ti) and / or indium (In) and / or cobalt (Co) and / or nickel (Ni) and / or copper (Cu) and / or manganese (Mn) and / or germanium (Ge). Tin oxide is preferably doped with arsenic (As) and / or fluorine (F) and / or nitrogen (N) and / or niobium (Nb) and / or phosphorus (P) and / or antimony (Sb) and / or aluminum (Al) and / or titanium (Ti) and / or gallium (Ga) and / or chromium (Cr) and / or cerium (Ce) and / or indium (In) and / or cobalt (Co) and / or nickel (Ni) and / or copper (Cu) and / or manganese (Mn) and / or germanium (Ge).

[0054] In a conventional manner, primary nanoparticles are advantageously in the form of aggregates or agglomerates, with an average diameter D50 between 50 nm and 300 nm, preferably between 100 nm and 200 nm.

[0055] The specific surface area of ​​the porous layer in step (c) is between 10 m² / g and 500 m² / g.

[0056] Conductive materials are deposited by means of atomic layer deposition (ALD) technology, or by immersing the material in a liquid phase containing a precursor and then converting the precursor into a conductive material.

[0057] In a second embodiment, a method for manufacturing a porous anode for a battery uses an intermediate substrate made of a polymer (e.g., PET) to produce a so-called "green tape." The green tape is then separated from its substrate to form a plate or sheet (hereinafter referred to as "plate" regardless of its thickness). These plates can be cut before or after separation from the intermediate substrate. The plates are then calcined to remove organic components. The plates are then sintered to solidify the nanoparticles until a mesoporous ceramic structure with a porosity between 25% and 50% is obtained. The thickness of the porous plate obtained in step (c) is advantageously between 5 µm and 300 µm. As described above, this facilitates the coating of the conductive material.

[0058] In a second embodiment, a metal sheet is also provided, with a thin intermediate layer of nanoparticles covering both sides, preferably the same nanoparticles as those constituting the electrode plate. The thickness of the thin layer is preferably less than 1 µm.

[0059] The metal sheet is then inserted between the two previously obtained porous electrode plates (e.g., two porous anode plates). The assembly is then hot-pressed, causing the intermediate thin layer of nanoparticles to transform through sintering and solidifying the electrode / substrate / electrode assembly to obtain a rigid integral assembly. During this sintering process, the bonding system between the electrode layer and the intermediate layer is established through atomic diffusion; this phenomenon is known as diffusion bonding. This assembly is made of two electrode plates of the same polarity (typically a metal sheet between two anodes), with the metal sheet between these two electrode plates of the same polarity forming a parallel connection.

[0060] One advantage of the second embodiment is that it can use inexpensive substrates, such as aluminum foil or copper foil. In fact, these foils cannot withstand the heat treatment used to solidify the deposited layer, and the layer is also protected from oxidation after heat treatment when it adheres to the electrode plate.

[0061] This component, obtained by diffusion bonding, can be produced separately as described above, and the resulting electrode / substrate / electrode sub-assemblies can be used to manufacture batteries. This component, obtained by diffusion bonding, can also be produced by stacking and hot-pressing the entire battery structure. In this case, a multilayer stack is formed, comprising a first porous anode layer according to the invention, its metal substrate, a second porous anode layer according to the invention, a solid electrolyte layer, a first cathode layer, its metal substrate, a second cathode layer, a new solid electrolyte layer, etc.

[0062] More precisely, the plate of the mesoporous ceramic electrode (especially the anode according to the invention) can also be bonded to both sides of the metal substrate (similar to a structure with deposits on both sides of the metal substrate). An electrolyte film (separator) is then deposited on this electrode / substrate / electrode (especially the anode / substrate / anode). The necessary cutting is then performed to manufacture a battery with multiple basic units, followed by stacking the sub-assemblies (typically head-to-tail) and hot-pressing to bond the electrodes together to the extent that a solid electrolyte is formed.

[0063] Alternatively, the stack can be formed as follows: a first electrode plate, a substrate coated with an adhesive (typically an intermediate thin layer of nanoparticles contained in the electrode material, which is used to fuse with the electrode material), a second electrode plate of the same polarity as the first electrode plate, a solid electrolyte (separator), an electrode plate of opposite polarity, and a substrate coated with an adhesive (typically an intermediate thin layer of nanoparticles contained in the electrode material, which is used to fuse with the electrode material). A final hot pressing is then performed to fuse the electrodes to the solid electrolyte and to fuse the electrode plates to the current collector.

[0064] In both of these variations, hot-press welding is performed at relatively low temperatures, which is possible due to the extremely small size of the nanoparticles. Therefore, the metal layer of the substrate does not oxidize.

[0065] If the electrode layer or electrode plate (note the use of the term "electrode plate," which includes "plate") exhibits sufficient conductivity, a separate current collector may not be necessary. This variant is primarily used in microcells.

[0066] In other embodiments of the components described below, a conductive adhesive (carried with graphite) or a molten gel deposit carrying conductive particles, or a metal strip, preferably having a low melting point (e.g., aluminum), is used. During thermomechanical processing (hot pressing), the metal foil deforms due to flow and can be used to form such a connection between plates.

[0067] A second object of the present invention is a porous anode comprising a porous layer having a porosity between 25% and 50% by volume, preferably between 28% and 43%, and more preferably between 30% and 40%. Its characteristic is that the porous layer comprises: A porous mesh of material A with pores having an average diameter of less than 50 nm, wherein a conductive material is coated on and within the pores forming the porous mesh, characterized in that material A is selected from niobium oxide and mixed oxides of niobium with titanium, germanium, cerium, lanthanum, copper, or tungsten, preferably selected from the group consisting of: Nb 2O 5-δ, Nb 18W 16O 93-δ, Nb 16W 5O 55-δ, 0 ≤ x < 1 and 0 ≤ δ ≤ 2; TiNb₂O₇ ... Ti 1-xM 1 xNb 2-yM 2 yO 7-zM 3 z, Li wTi 1-xM 1 xNb 2-yM 2 yO 7-zM 3 z, where M1 and M2 are each selected from at least one element chosen from the group consisting of Nb, V, Ta, Fe, Co, Ti, Bi, Sb, As, P, Cr, Mo, W, B, Na, Mg, Ca, Ba, Pb, Al, Zr, Si, Sr, K, Cs, and Sn. M1 and M2 may be the same or different from each other. M3 is at least one halogen, wherein 0 ≤ w ≤ 5, 0 ≤ x ≤ 1, 0 ≤ y ≤ 2, and z ≤ 0.3; TiNb2O7-zM3z, LiwTiNb2O7-zM3z, wherein M3 is at least one halogen, preferably selected from F, Cl, Br, I, or mixtures thereof, and 0 < z ≤ 0.3; Ti 1-xGe xNb 2-yM 1 yO 7-z, Li wTi 1-xGe xNb 2-yM 1 yO 7-z, Ti 1-xCe xNb 2-yM 1 yO 7-z, Li wTi 1-xCe xNb 2-yM 1 yO 7-z, where M1 is at least one element selected from the group consisting of Nb, V, Ta, Fe, Co, Ti, Bi, Sb, As, P, Cr, Mo, W, B, Na, Mg, Ca, Ba, Pb, Al, Zr, Si, Sr, K, Cs, Ce, and Sn, wherein 0 ≤ w ≤ 5, 0 ≤ x ≤ 1, 0 ≤ y ≤ 2, and z ≤ 0.3; Ti 1-xGe xNb 2-yM 1 yO 7-zM 2 z, Li wTi 1-xGe xNb 2-yM 1 yO 7-zM 2 z, Ti 1-xLa xNb 2-yM 1 yO 7-zM 2 z, Li wTi 1-xLa xNb 2-yM 1 yO 7-zM 2 z, Ti 1-xCu xNb 2-yM 1 where M1 and M2 are each selected from at least one element chosen from the group consisting of Nb, V, Ta, Fe, Co, Ti, Bi, Sb, As, P, Cr, Mo, W, B, Na, Mg, Ca, Ba, Pb, Al, Zr, Si, Sr, K, Cs, Ce, and Sn; M1 and M2 may be the same or different from each other, wherein 0 ≤ w ≤ 5, 0 ≤ x ≤ 1, 0 ≤ y ≤ 2, and z ≤ 0.3; this anode can be obtained by the method according to the invention.

[0068] A third object of the present invention is a method for manufacturing a battery, preferably a lithium-ion battery, by implementing the method for manufacturing a porous anode according to the present invention or using a porous anode according to the present invention.

[0069] This method is a method for manufacturing a battery, the battery comprising at least one porous anode, at least one separator, and at least one porous cathode according to the present invention. The method is characterized by...

[0070] (a) Providing a first substrate, a second substrate, a first colloidal suspension or paste, a second colloidal suspension, and a third colloidal suspension, wherein...

[0071] The first colloidal suspension or paste comprises aggregates or clusters of monodisperse primary nanoparticles of at least one anode active material A, wherein the average diameter D50 of the monodisperse primary nanoparticles is between 2 nm and 100 nm, preferably between 2 nm and 60 nm, and the average diameter D50 of the aggregates or clusters is between 50 nm and 300 nm (preferably between 100 nm and 200 nm). Material A is selected from niobium oxide and mixed oxides of niobium with titanium, germanium, cerium, lanthanum, copper, or tungsten, preferably from the group consisting of: Nb₂O₅⁻δ, Nb₁₈W₁₆O₉₃⁻δ, Nb₁₆W₅O₅⁻δ, 0 ≤ x < 1 and 0 ≤ δ ≤ 2; TiNb₂O₇⁻δ, Ti₁₋ₓM₁₋ₓNb₂₋₂yO₇⁻δ, Li₂W₁₋ₓM₁₋ₓNb₂₋₂yO₇⁻δ, Li₂W₁₋ₓM₁₋ₓNb₂₋₂yO₇⁻δ, wherein M₁ and M₂ are each selected from at least one element from the group consisting of Nb, V, Ta, Fe, Co, Ti, Bi, Sb, As, P, Cr, Mo, W, B, Na, Mg, Ca, Ba, Pb, Al, Zr, Si, Sr, K, Cs, and Sn, wherein M₁ and M₂ are selected from at least one element from the group consisting of Nb, V, Ta, Fe, Co, Ti, Bi, Sb, As, P, Cr, Mo, W, B, Na, Mg, Ca, Ba, Pb, Al, Zr, Si, Sr, K, Cs, and Sn. 2 can be the same or different from each other, where 0 ≤ w ≤ 5, 0 ≤ x ≤ 1, 0 ≤ y ≤ 2 and 0 ≤ δ ≤ 0.3; Ti 1-xM 1 xNb 2-yM 2 yO 7-zM 3 z, Li wTi 1-xM 1 xNb 2-yM 2 yO 7-zM 3 z, where M 1 and M 2 are each at least one element selected from the group consisting of Nb, V, Ta, Fe, Co, Ti, Bi, Sb, As, P, Cr, Mo, W, B, Na, Mg, Ca, Ba, Pb, Al, Zr, Si, Sr, K, Cs and Sn, M 1 and M 2 can be the same or different from each other, M 3 is at least one halogen, where 0 ≤ w ≤ 5, 0 ≤ x ≤ 1, 0 ≤ y ≤ 2 and z ≤ 0.3; TiNb₂O₇₇M₃₇, Li₂wTiNb₂O₇₇M₃₇, wherein M₃ is at least one halogen, preferably selected from F, Cl, Br, I or mixtures thereof, and 0 < z ≤ 0.3; Ti₁₋ₓGe₁₋ₓNb₂₇₇M₁₇yO₇₇, Li₂wTi₁₋ₓGe₁₋ₓNb₂₇₇M₁₇yO₇₇, Ti₁₋ₓLa₁₋ₓNb₂₇₇M₁₇yO₇₇, Li₂wTi₁₋ₓCe₁₋ₓNb₂₇₇M₁₇yO₇₇, wherein M₃ is at least one halogen, preferably selected from F, Cl, Br, I or mixtures thereof, and 0 < z ≤ 0.3; 1 is selected from at least one element of the group consisting of Nb, V, Ta, Fe, Co, Ti, Bi, Sb, As, P, Cr, Mo, W, B, Na, Mg, Ca, Ba, Pb, Al, Zr, Si, Sr, K, Cs, Ce, and Sn, wherein 0 ≤ w ≤ 5, 0 ≤ x ≤ 1, 0 ≤ y ≤ 2, and z < 1, preferably 0 ≤ w ≤ 5, 0 ≤ x ≤ 1, 0 ≤ y ≤ 2, and z < 0.3;Ti 1-xGe xNb 2-yM 1 yO 7-zM 2 z, Li wTi 1-xGe xNb 2-yM 1 yO 7-zM 2 z, Ti 1-xLa xNb 2-yM 1 yO 7-zM 2 z, Li wTi 1-xLa xNb 2-yM 1 yO 7-zM 2 z. Ti 1-xCu 2 z, where M 1 and M 2. Each element is selected from at least one element of the group consisting of Nb, V, Ta, Fe, Co, Ti, Bi, Sb, As, P, Cr, Mo, W, B, Na, Mg, Ca, Ba, Pb, Al, Zr, Si, Sr, K, Cs, Ce, and Sn; M1 and M2 may be the same or different from each other, wherein 0 ≤ w ≤ 5, 0 ≤ x ≤ 1, 0 ≤ y ≤ 2, and z ≤ 0.3;

[0072] It is known that the first substrate and / or the second substrate can be a substrate or intermediate substrate that can serve as a current collector.

[0073] The second colloidal suspension comprises aggregates or clusters of monodisperse primary nanoparticles of at least one cathode active material C, wherein the average diameter D50 of the monodisperse primary nanoparticles is between 2 nm and 100 nm, preferably between 2 nm and 60 nm, and the average diameter D50 of the aggregates or clusters is between 50 nm and 300 nm (preferably between 100 nm and 200 nm).

[0074] The third colloidal suspension comprises aggregates or clusters of nanoparticles of at least one inorganic material E (preferably an electrical insulator), wherein the average diameter D50 of the nanoparticles is between 2 nm and 100 nm, preferably between 2 nm and 60 nm, and the average diameter D50 of the aggregates or clusters is between 50 nm and 300 nm (preferably between 100 nm and 200 nm).

[0075] (b) Depositing an anolyte layer from the first colloidal suspension provided in step (a) on at least one side of a first substrate and a cathode layer from the second colloidal suspension provided in step (a) on at least one side of a second substrate, preferably by means of a method selected from the group consisting of: electrophoresis, extrusion, printing methods (preferably inkjet printing and quick-drying printing) and coating methods (preferably roller coating, curtain coating, doctor blade coating, slit extrusion coating or dip coating);

[0076] (c) Drying the anode layer and cathode layer obtained in step (b), and if necessary, after separating the anode layer and cathode layer from their intermediate substrate, consolidating each layer by pressure and / or heating to obtain a porous (preferably porous and inorganic) anode layer and a porous (preferably porous and inorganic) cathode layer respectively;

[0077] (d) Optionally, a coating of conductive material may be deposited on and within the pores of the porous anode layer and / or cathode layer to form a porous anode and a porous cathode;

[0078] (e) Depositing a porous inorganic layer from the third colloidal suspension provided in step (a) onto the porous anode and / or porous cathode obtained in step (c) or (d), wherein the deposition is performed by a technique selected from the group consisting of: electrophoresis, extrusion, printing methods (preferably inkjet printing and fast-drying printing) and coating methods (preferably roller coating, curtain coating, doctor blade coating, slit extrusion coating or dip coating);

[0079] (f) Drying the porous inorganic layer having the structure obtained in step (e), preferably under airflow and heat treatment at a temperature above 130°C, preferably between about 300°C and about 600°C, if necessary, pressing the layer separated from the intermediate substrate onto a metal sheet that can act as a current collector before heat treatment;

[0080] (g) The porous anode obtained in step (d) or (e) is continuously stacked face-to-face with the porous cathode obtained in step (d) or (e), wherein the resulting stack comprises at least one porous inorganic layer as obtained in step (e) forming a spacer;

[0081] (h) The stack obtained in step (g) is hot-pressed at a temperature between 120°C and 600°C to obtain a battery comprising at least one porous anode, at least one separator and at least one porous cathode.

[0082] The heat treatment in step (h) is performed after the thin film separator is deposited on the electrode.

[0083] The product obtained in step (h) is then impregnated with an ion-conducting polymer or a polymer that has been made ion-conducting, or even with a liquid electrolyte containing at least one lithium salt, advantageously selected from the group consisting of: An electrolyte consisting of at least one aprotic solvent and at least one lithium salt; An electrolyte consisting of at least one ionic liquid and at least one lithium salt; A mixture of at least one aprotic solvent, at least one ionic liquid, and at least one lithium salt; Polymers that possess ion conductivity through the addition of at least one lithium salt; and Polymers that possess ion conductivity by adding liquid electrolytes to the polymer phase or to the mesoporous structure.

[0084] These manufacturing methods can produce completely solid batteries with fine ceramic separators. These separators are well impregnated with ionic liquids and can withstand high temperatures.

[0085] Another object of the present invention is a lithium-ion battery with a capacity of no more than 1 mAh, which can be obtained by the method according to the invention. In this case, the battery comprises an anode according to the invention or an anode that can be obtained by the method according to the invention. The specific capacity of the anode is advantageously greater than 200 mAh / g, preferably greater than 250 mAh / g.

[0086] The ultimate objective of this invention is the use of the battery according to the invention at temperatures below -10°C and / or above 50°C, preferably below -20°C and / or above 60°C, and even more preferably below -30°C and / or above 70°C.

[0087] In an advantageous embodiment of the invention, the surface capacitance of the anode of the battery is lower than that of the cathode, which improves the temperature stability of the battery.

[0088] Generally, fabricating fully solid, sintered, and multilayered structures presents numerous challenges. This requires heating to high temperatures for sintering, which can degrade the electrode material and cause interdiffusion at the interfaces. According to one of the fundamental features of the invention, the method utilizes nanoparticles, which lower the sintering temperature. Furthermore, partial sintering can advantageously be performed to obtain a mesoporous structure. Moreover, this sintering can be performed on the electrode layers or plates before assembly with the separator, avoiding contact between ceramic layers of different materials during sintering. For the separator, it is advantageous to select a material with a relatively low melting point and inertness to electrode contact, enabling its assembly at relatively low temperatures. Simple Explanation of the Diagram

[0089] Figure 1 shows the discharge curves obtained under two different conditions using an anode having a Ti 0.95Ge 0.05Nb 2O 7 according to the present invention. Implementation

[0090] 1. Definition

[0091] In this paper, the size of a particle is defined by its largest dimension. A "nanoparticle" is defined as any particle or object with at least one dimension less than or equal to 100 nm in the nanometer scale.

[0092] In this paper, the term "conductive oxide" is defined as both conductor oxide and semiconductor oxide.

[0093] In this document, electrically insulating materials or layers, preferably electrically insulating and ionicly conductive layers, are materials or layers with a resistance greater than 10⁵ ohm-cm (Ω⋅cm) (resisting the passage of electrons). "Ionic liquid" refers to any liquid salt capable of conducting electricity, differing from all molten salts by having a melting point below 100°C. Some of these salts remain liquid at ambient temperature and do not solidify even at very low temperatures. Such salts are called "ionic liquids at ambient temperature."

[0094] The term "mesoporous material" refers to any solid having pores in its structure called "mesopores," which have an intermediate size between micropores (width less than 2 nm) and macropores (width greater than 50 nm), that is, a size between 2 nm and 50 nm. This terminology corresponds to the terminology used by the International Union for Pure and Applied Chemistry (IUPAC), which is of ordinary knowledge in the art. Therefore, even though mesopores, as defined above, have nanodimensionality as defined for nanoparticles, the term "nanopore" is not used here; pores with known sizes smaller than mesopores are referred to as "micropores" by those of ordinary knowledge in the art.

[0095] An introduction to the concept of porosity (and the aforementioned terminology) can be found in the article "Texture des materiaux pulverulents or poreux" ("Texture of powdered or porous materials") published by F. Rouquerol et al. in the collection "Techniques de l'Ingénieur" ("Engineering techniques") Analyse and Caractérisation, section P 1050. This article also describes techniques for characterizing porosity, especially the BET method.

[0096] In this invention, the term "mesoporous layer" refers to a layer having mesopores. As described below, in these layers, the mesopores make a significant contribution to the total pore volume, which is expressed in the following description as "the mesoporous layer has a porosity of greater than X% by volume," wherein X% is preferably greater than 25%, more preferably greater than 30%, and more preferably between 30% and 50% of the total volume of the layer.

[0097] According to the IUPAC definition, the term "aggregate" refers to a weakly bound group of primary particles. In this case, these primary particles are nanoparticles, the diameter of which can be determined by transmission electron microscopy. According to techniques known to those skilled in the art, the aggregates of primary nanoparticles can usually be broken down (i.e., reduced to primary nanoparticles) under the influence of ultrasound, thus suspending them in the liquid phase.

[0098] According to the IUPAC definition, the term "aggregate" is defined as a strongly bound combination of primary particles or aggregates.

[0099] In this invention, the term "electrolyte layer" refers to a layer in an electrochemical device that functions according to its purpose. For example, in the case of a secondary lithium-ion battery, the term "electrolyte layer" refers to a "porous inorganic layer" impregnated with a lithium-ion carrier phase. The electrolyte layer is an ionic conductor but an electrical insulator.

[0100] According to the terminology used by those skilled in the art, the porous inorganic layer in an electrochemical device is also referred to here as a "separator".

[0101] According to the present invention, the "porous inorganic layer", preferably mesoporous, can be electrophoretically deposited by means of: dip coating, hereinafter referred to as "dip coating"; inkjet printing, hereinafter referred to as "inkjet printing"; "roll coating"; "curtain coating"; or "scalpel coating", which are derived from a suspension of nanoparticle aggregates or clusters, preferably from a concentrated suspension of agglomerates containing nanoparticles.

[0102] 2. Preparation of Nanopowder Suspension

[0103] In this invention, monodisperse crystalline nanoparticles with a primary particle size of less than 100 nm are preferably used in electrode and separator layers. This promotes necking between primary particles (agglomerated or non-agglomerated) during the consolidation process. Consolidation can then be carried out at a relatively low temperature, where the primary particles are known to be in a crystalline state; the purpose of this treatment is to prevent further crystallization. For certain chemical compositions, specific synthetic methods are required to obtain a population of monodisperse crystalline nanoparticles.

[0104] Typically, compositions of the TNO (TiNb₂O₇) type have very low conductivity. In batteries, to provide high power, the particles must be very small. Furthermore, as described below, it is advantageous to coat a thin layer of conductive material onto a mesoporous mesh to compensate for the low conductivity of the anode material; for this purpose, a thin layer of graphite carbon (instead of diamond-like carbon) is used.

[0105] It is known that TNO(TiNb₂O₇) type particles can be synthesized hydrothermally with a dispersion size between approximately 50 nm and approximately 300 nm; however, controlling the dispersion size is difficult and the dispersion range is large. This synthesis results in amorphous particles, which then require crystallization by heat treatment at high temperatures, such as approximately 1000°C for about 30 minutes. During this crystallization process, the particles grow uncontrollably, which expands the dispersion size. Alternatively, there are solid-state synthesis methods, which also require high temperatures to achieve a uniform chemical composition. In this invention, it is preferable to use primary nanoparticles, aggregated or non-aggregated, with a size less than 100 nm, more preferably less than 60 nm, and even more preferably less than 40 nm. Such nanoparticles can be obtained by various methods.

[0106] According to one method, salts, complexes, or alcohols (e.g., ethanolates) of the cations of the desired metal element are mixed to obtain a completely uniform distribution at the atomic scale. Polymers are used to fix the distribution of the molecules, ions, or complexes containing the metal element. These polymers are then removed by heat treatment, leaving only the inorganic components at the atomic scale. Simple calcination at a relatively low temperature yields the desired crystalline phase at the nanoparticle scale. Organic materials that can strongly degas during heat treatment and contribute to obtaining mesoporous aggregates can be added.

[0107] An example of this synthesis is the "Pechini process," a sol-gel type process in which a cation of the desired phase (in this case, Nb, Ti, and others) is misculated with an organic molecule (e.g., citric acid or ethylenediaminetetraacetic acid, EDTA) and introduced into a polymer matrix (e.g., a polyol such as polyethylene glycol or polyvinyl alcohol). This results in a very uniform distribution of the misculated and diluted cations. Subsequently, the polymer and misculated organic molecules are eliminated by pyrolysis, thereby forming the target inorganic oxide. Calcination at approximately 700°C yields crystalline nanoparticles. This reaction can adjust the particle size, thereby reducing the concentration of cations in the reduced polymer matrix.

[0108] As an example, to obtain a suspension of cathode material particles, the Pechini reaction described in the article "Synthesis and Electrochemical Studies of Spinel Phase LiMn2O4 Cathode Materials Prepared by the Pechini Process" (W. Liu, GC Farrington, F. Chaput, B. Dunn, J. Electrochem. Soc., vol.143, No.3, 1996) can be used to synthesize LiMn2O4 powder composed of clusters of nanoparticles. After a calcination step at 600°C, the powder contains clusters typically between 50 nm and 100 nm in size, and the size of the crystalline primary nanoparticles typically ranges between 10 nm and 30 nm, depending on the synthesis conditions.

[0109] A particularly preferred anode material is LiwTi1-xGexNb2-yM1yO7-zM3z, wherein M1 is at least one element selected from the group consisting of Nb, V, Ta, Fe, Co, Ti, Bi, Sb, As, P, Cr, Mo, W, B, Na, Mg, Ca, Ba, Pb, Al, Zr, Si, Sr, K, Cs, Ce, and Sn, wherein 0 ≤ w ≤ 5, 0 ≤ x ≤ 1, 0 ≤ y ≤ 2, and z ≤ 0.3, and M3 is at least one halogen. Preferably, 0 < x ≤ 1, more preferably 0.1 ≤ x ≤ 1, because the presence of germanium in the anode composition reduces the battery resistance and increases its power.

[0110] It is worth noting that germanium's redox properties allow it to produce compounds with almost identical lithium insertion behavior to its germanium-free analogues. Even though the redox potential of Ge⁴⁺ / Ge³⁺ ions is slightly lower than that of the Ti⁴⁺ / Ti³⁺ group, this potential remains high enough to avoid lithium deposition (precipitation) during recharging and to increase the energy density of the anode. Other active anode materials A that are particularly preferred are Ti 1-xGe yO 7-zM 2 z、Ti 1-xCu xNb 2-yM 1 yO 7-zM 2 z、Li wTi 1-xCu xNb 2-yM 1 yO 7-zM 2 z、Ti 1-xCe xNb 2-yM 1 yO 7-zM 2 z、Li wTi 1-xCe xNb 2-yM 1 yO 7-zM 2 z, where M1 and M2 are each selected from at least one element chosen from the group consisting of Nb, V, Ta, Fe, Co, Ti, Bi, Sb, As, P, Cr, Mo, W, B, Na, Mg, Ca, Ba, Pb, Al, Zr, Si, Sr, K, Cs, Ce, and Sn; M1 and M2 can be the same or different from each other. Where 0 ≤ w ≤ 5, 0 ≤ x ≤ 1, 0 ≤ y ≤ 2 and z ≤ 0.3.

[0111] For these active materials of the anode, it is preferable that 0 < x ≤ 1, and more preferably 0.1 ≤ x ≤ 1, because the presence of germanium, cerium, lanthanum or copper in the composition of the anode will improve the cycle efficiency of the battery.

[0112] For Li wTi 1-xCu xNb 2-yM 1 yO 7-zM 2 z, it is preferable that 0 < x ≤ 1, and more preferably 0.1 ≤ x ≤ 1, because the presence of copper in the active material of the anode can also improve the battery power.

[0113] Batteries with a mesoporous anode made of this material can be recharged very quickly and have a very good volumetric energy density, which is greater than that obtained by conventional Li 4Ti 5O 12 anodes.

[0114] According to the present invention, the cathode material is advantageously selected from the group consisting of: LiCoPO4; LiMn1.5Ni0.5O4; LiFexCo1-xPO4, where 0 < x < 1; LiNi1 / xCo1 / yMn1 / zO2, where x+y+z = 10; Li1.2Ni0.13Mn0.54Co0.13O2; LiMn1.5Ni0.5-xXxO4, where X is selected from Al, Fe, Cr, Co, Rh, Nd, Sc, Y, Lu, La, Ce, Pr, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, 0 < x < 0.1; LiNi0.8Co0.15Al0.05O2; Li2MPO4F, where M = Fe, Co, Ni or a mixture of these different elements; LiMPO 4F, where M = V, Fe, T or a mixture of these different elements; LiMSO 4F, where M = Fe, Co, Ni, Mn, Zn, Mg; LiNi 1 / xMn 1 / yCo 1 / zO 2, where x+y+z = 10; LiCoO 2.

[0115] For high-capacitance cathodes, especially LiNi 1 / xMn 1 / yCo 1 / zO 2 with x+y+z = 10, LiNi 0.8Co 0.15Al 0.05O 2 and LiCoO 2 are preferred.

[0116] For example, LiNi xMn yCo zO 2 (also known as NMC) can be used, preferably x + y + z = 1, and more preferably x:y:z = 4:3:3 (a material known as NMC433).

[0117] 3. Deposition and consolidation of the layers

[0118] Typically, nanoparticle suspensions are deposited onto substrates using any suitable technique, particularly by methods selected from the group consisting of: electrophoresis, extrusion, printing (preferably inkjet or fast-drying printing), and coating (preferably blade coating, roller coating, curtain coating, dip coating, or slot extrusion coating). The suspension is usually in ink form, i.e., a highly fluid liquid, but can also have a paste-like consistency. The deposition technique and method must be compatible with the viscosity of the suspension, and vice versa.

[0119] Next, the deposited layer is dried. Then, the layer is consolidated to obtain the desired ceramic mesoporous structure. This consolidation is described below. It may involve heat treatment, possibly thermomechanical treatment, typically hot pressing. During this thermomechanical treatment, the electrode layer will be free of any organic components and organic residues (e.g., the liquid phase of the nanoparticle suspension and any interfacial active products), becoming an inorganic (ceramic) layer. The consolidation of the plate is preferably performed after separation from its intermediate substrate, as the latter may degrade during this process.

[0120] The deposition, drying, and consolidation of the layers can cause certain problems as described below. These problems are partly related to the internal stresses generated by shrinkage during layer consolidation.

[0121] According to the first embodiment, each electrode layer is deposited on a substrate that can serve as a current collector. For this purpose, a metal sheet (i.e., a laminated metal sheet) is preferred. A layer containing a suspension of nanoparticles or nanoparticle aggregates can be deposited on both sides using the deposition technique described above.

[0122] When the electrode thickness is to be increased, shrinkage due to consolidation is observed to cause the layer to crack or shear stress at the interface between the substrate (with fixed dimensions) and the ceramic electrode. When the shear stress exceeds a threshold, the layer will separate from the substrate.

[0123] To avoid this phenomenon, it is preferable to increase the electrode thickness through a continuous deposition-sintering operation. A first variant of the first embodiment of the deposited layer yields good results but suffers from poor productivity. Alternatively, in a second variant, a layer of greater thickness is deposited on both sides of a perforated substrate. The perforations need to be of sufficient diameter to allow the two layers to contact at the perforations. Therefore, during consolidation, nanoparticles and / or agglomerates of the electrode material that contact the perforations through the substrate are fused together to form adhesion points (fusion points between the deposits on both sides). This limits the loss of adhesion of the layer to the substrate during the consolidation step.

[0124] According to the second embodiment, the electrode layer is not deposited on a substrate that can serve as a current collector, but on a temporary intermediate substrate. In particular, a relatively thick layer (green sheet) can be deposited from a suspension of more concentrated nanoparticles and / or nanoparticle aggregates (i.e., less fluid, preferably paste-like). These thick layers are deposited by, for example, coating methods (refer to blade coating or blade forming techniques). The intermediate substrate can be a polymer sheet, such as polyethylene terephthalate (PET). These layers do not crack during the drying process. For consolidation by heat treatment (preferably after drying), they can be separated from the substrate to produce a so-called "green" electrode plate, which becomes a self-supporting mesoporous ceramic plate after calcination heat treatment and partial sintering.

[0125] Next, a three-layer stack is formed, where two electrode plates with the same polarity are separated by a metal sheet that can act as a current collector. This stack is then assembled by a thermomechanical process, which includes pressurization and heating, preferably simultaneously. In one variation, to facilitate bonding between the ceramic plate and the metal sheet, the interface may be coated with a conductive bonding layer. This layer may be a molten gel layer (preferably of a type where the chemical composition of the electrode can be finalized after heat treatment), possibly containing conductive material particles, which forms a ceramic bond between the via electrode and the metal sheet. This layer may also be formed from a thin layer of unsintered electrode nanoparticles, a thin layer of conductive adhesive (e.g., containing graphite particles), or a metal layer of a low-melting-point metal.

[0126] The metal sheet is preferably a laminated sheet, i.e., obtained by laminating. Optionally, lamination can be performed before final annealing, which, in metallurgical terms, can be softening (partial or complete) or recrystallization annealing. Electrochemically deposited sheets, such as electrodeposited copper or nickel sheets, can also be used.

[0127] In any case, a mesoporous ceramic electrode without organic binder is obtained on either side of the metal substrate serving as the current collector.

[0128] In one variation of the invention, the battery is manufactured without using a metal current collector. This is possible if the electrode plates have sufficient conductivity to ensure that electrons can pass through both ends of the electrodes. Sufficient conductivity can be observed if the electrode material itself has very high conductivity (in the case of materials such as LiCoO₂ or Nb₁₆W₅O₅₅) or if a conductive layer is coated on the surface of the mesopore.

[0129] 4. Deposition of thin layers of electronic conductors

[0130] This step is optional. In practice, depending on the desired electrode powder (which also affects its thickness) and the conductivity of the electrode material, this treatment to improve electrode conductivity may or may not be necessary. For example, TNO (titanium niobium oxide) generally has lower conductivity than NWO (tungsten niobium oxide), so for the same thickness, an NWO anode layer would require more conductive film deposition. Similarly, for the same material, a thicker electrode layer would require more conductive film than a thinner electrode layer.

[0131] The anode material (more specifically titanium oxide, niobium oxide, and mixed oxides of titanium and niobium, especially TiNb₂O₇, abbreviated as TNO) and cathode material used in this invention are poor electronic conductors. Batteries containing these materials will therefore have high series resistance, which means ohmic energy loss, especially with thick electrodes. According to this invention, a nanolayer of conductive material is deposited within a mesoporous network, i.e., within the pores, to ensure good conductivity of the electrode. The greater the need for increased conductivity, the thicker the deposit. Therefore, thick electrodes with low series resistance and high power can be achieved.

[0132] To solve this problem, according to an optional feature of the present invention, a conductive material is coated and deposited on and within the pores of the porous layer of the anode material.

[0133] In fact, as mentioned above, during the consolidation process of the anode material layer, the anode material nanoparticles naturally "weld" together to produce a porous and rigid three-dimensional structure without any organic binder. This porous layer is preferably a mesoporous layer, which is perfectly suitable for surface treatment applications using gaseous or liquid methods, and its depth of penetration into the open porous structure of the layer.

[0134] Deposition can be performed in a highly advantageous manner using coating (i.e., deposition) techniques (also known as "conformal deposition"), which faithfully reproduces the atomic morphology of the substrate to which it is applied, penetrating deep into the open pore network of the layer. The conductive material can be carbon.

[0135] Atomic Layer Deposition (ALD) or Chemical Solution Deposition (CSD) techniques are known to be suitable. These can be applied to the cell after fabrication, before and / or after the deposition of separator particles, and before and / or after cell assembly. ALD deposition is performed layer-by-layer using a cyclic method and can form a coating that closely reproduces the morphology of the substrate. The coating covers the entire surface of the electrode. The coating thickness is typically between 1 nm and 5 nm.

[0136] ALD deposition is typically performed at temperatures between 100°C and 300°C. It is crucial that the layer is free of organic materials; it must not contain any organic binders. Stabilizing binders used to stabilize the suspension must be removed through suspension purification and / or during heat treatment of the layer after drying. In fact, at the ALD deposition temperatures, organic materials forming organic binders (e.g., polymers contained in ink doctor blade-formed electrodes) risk degradation and contamination of the ALD reactor. Furthermore, the presence of residual polymers in contact with the electrode active material particles may prevent ALD coating from covering the entire particle surface, thus reducing its effectiveness.

[0137] CSD deposition technology can also use conductive material precursors to form a coating that faithfully reproduces the morphology of the substrate and covers the entire surface of the electrode. The thickness of this coating is typically less than 5 nm, preferably between 1 nm and 5 nm. It must then be converted into a conductive material. In the case of carbon precursors, this is done by pyrolysis, preferably under an inert gas (e.g., nitrogen).

[0138] A conductive material layer can be formed by immersing the conductive material precursor in a liquid phase and then transforming the precursor into a conductive material through heat treatment. This method is simpler, faster, easier to operate, and less expensive than atomic layer deposition (ALD). Advantageously, the conductive material precursor is selected from organic salts containing one or more metal elements capable of forming conductive oxides after heat treatment such as calcination, preferably forming conductive oxides after heat treatment in air or an oxidizing environment. These metal elements are preferably metal cations and can be advantageously selected from tin, zinc, indium, gallium, or mixtures of two, three, or four of these elements. The organic salt is preferably selected from alkoxides capable of forming at least one metal cation of a conductive oxide after heat treatment such as calcination, oxalates capable of forming at least one metal cation of a conductive oxide after calcination, and acetates capable of forming at least one metal cation of a conductive oxide after heat treatment such as calcination, and preferably forming conductive oxides after heat treatment in air or an oxidizing environment.

[0139] Advantageously, the conductive material can be a conductive oxide material, preferably selected from: tin oxide (SnO 2), zinc oxide (ZnO), indium oxide (In 2O 3), gallium oxide (Ga 2O 3), mixtures of two of these oxides (e.g., indium tin oxide corresponding to a mixture of indium oxide (In 2O 3) and tin oxide (SnO 2), mixtures of three of these oxides, or mixtures of four of these oxides. The zinc oxide-based doped oxide is preferably doped with gallium (Ga) and / or aluminum (Al) and / or boron (B) and / or beryllium (Be) and / or chromium (Cr) and / or cerium (Ce) and / or titanium (Ti) and / or indium (In) and / or cobalt (Co) and / or nickel (Ni) and / or copper (Cu) and / or manganese (Mn) and / or germanium (Ge). The indium oxide-based doped oxide is preferably doped with tin (Sn) and / or gallium (Ga) and / or chromium (Cr) and / or cerium (Ce) and / or titanium (Ti) and / or indium (In) and / or cobalt (Co) and / or nickel (Ni) and / or copper (Cu) and / or manganese (Mn) and / or germanium (Ge). Tin oxide is preferably doped with arsenic (As) and / or fluorine (F) and / or nitrogen (N) and / or niobium (Nb) and / or phosphorus (P) and / or antimony (Sb) and / or aluminum (Al) and / or titanium (Ti) and / or gallium (Ga) and / or chromium (Cr) and / or cerium (Ce) and / or indium (In) and / or cobalt (Co) and / or nickel (Ni) and / or copper (Cu) and / or manganese (Mn) and / or germanium (Ge).

[0140] To obtain a layer of conductive material (preferably a conductive oxide material) from alkoxides, oxalates, or acetates, a porous layer can be immersed in a solution rich in the desired conductive material precursor. The electrode is then dried and heat-treated, preferably in air or an oxidizing environment at a temperature sufficient to pyrolyze the desired conductive material precursor. Thus, a coating of conductive material, preferably a conductive oxide material, is formed on the inner surface of the electrode, and is perfectly distributed.

[0141] The use of conductive oxide coatings on and within the pores of porous layers, instead of carbon coatings, enhances the electrochemical performance of the electrode at high temperatures and significantly improves its stability. Using conductive oxide coatings instead of carbon coatings provides better conductivity to the final electrode. In fact, the presence of conductive oxide layers on or within the pores of porous layers or plates, especially conductive oxide coatings, can improve the final characteristics of the electrode, particularly its voltage resistance, temperature resistance during sintering, and electrochemical stability, especially when in contact with the electrolyte, thereby reducing the electrode's polarization resistance, even when the electrode is thick. It is particularly advantageous to use conductive oxide coatings on and within the pores of the porous layer of the electrode active material, especially In₂O₃, SnO₂, ZnO, Ga₂O₃, or mixtures of one or more of these oxides, when the electrode is thick and / or when the resistance of the active material of the porous layer is too high.

[0142] The electrode according to the present invention is porous, preferably mesoporous, and has a large specific surface area. The increased specific surface area of ​​the electrode expands the exchange surface, thereby increasing the power of the battery, but it also accelerates parasitic reactions. The presence of these conductive coatings in the form of oxides on and within the pores of the porous layer will inhibit these parasitic reactions.

[0143] Furthermore, due to their very large specific surface area, the impact of these conductive coatings on the conductivity of the battery is more pronounced compared to conventional electrodes with smaller specific surface areas, even if the deposited conductive coating is thin. These conductive coatings, deposited on and within the pores of the porous layer, endow the electrode with excellent conductivity.

[0144] Basically, the synergistic combination of a porous layer or plate made of electrode active material and a conductive coating in the form of oxides deposited on and inside the pores of the porous layer or plate can improve the final characteristics of the electrode, especially to obtain a thick electrode without increasing the internal resistance of the electrode.

[0145] Furthermore, conductive coatings in oxide form on and within the pores of porous layers are simpler and cheaper to achieve than carbon coatings. In fact, in the case of conductive material coatings in oxide form, the transformation from the conductive material precursor to the conductive material coating does not need to be carried out in an inert environment, unlike the case of carbon coatings.

[0146] In this variant of depositing a nanolayer of conductive material, it is preferable that the average diameter D50 of the primary particles of the electrode material is at least 10 nm to prevent the conductive layer from clogging the open pores of the electrode layer.

[0147] In the case of depositing self-supporting electrode plates, this treatment can be performed on the perforated ceramic plate before bonding to the current collector.

[0148] 5. Selection of materials for the layers

[0149] To obtain high-efficiency batteries, it is necessary to optimize their specific capacity and voltage. This may mean that there are limitations in the selection of different materials, which must be compatible with each other and stable under the potential conditions for battery operation.

[0150] The cathode will be discussed in this section. The anode material, as described above, is an oxide containing niobium. These anode materials have a specific capacity greater than 160 mAh / g, a lithium insertion voltage greater than 0.5V / Li, and can be rapidly recharged without the risk of lithium deposition. Furthermore, the anode materials used according to the present invention do not exhibit significant volume changes during charging and discharging, making them suitable for use in completely solid batteries.

[0151] Regarding the cathode material, in the method of manufacturing the battery according to the present invention, as described in the invention summary, in the first embodiment, when the specific capacity of the porous cathode is greater than 120 mAh / g and operates at a voltage less than 4.5V, The cathode active material C is advantageously selected from the group consisting of: LiCoPO₂; LiNi 1 / xCo 1 / yMn 1 / zO₂, where x+y+z = 10; Li 1.2Ni 0.13Mn 0.54Co 0.13O₂; Li 2MPO 4F; LiMSO 4F, where M = Fe, Co, Ni, Mn, Zn, Mg or a mixture of these different elements; The first and second substrates are selected from the group consisting of the following metals: Cu, Al, stainless steel, Mo, W, Ta, Ti, Cr, Ni, and alloys formed from at least one of these elements. It is known that if the cathode layer is a cathode plate initially deposited on an intermediate substrate, and is heat-treated after separation from its initial substrate and before contact with the substrate serving as a current collector, the plate can be plated on a low-melting-point substrate, such as an aluminum sheet.

[0152] The characteristics of this method are more specifically as follows:

[0153] In step (i), the structure obtained between step (f) and step (g) or the battery obtained after step (h) is immersed in an electrolyte with electrochemical stability up to at least 4.5 V, selected from the group consisting of: An electrolyte consisting of at least one aprotic solvent and at least one lithium salt; An electrolyte consisting of at least one ionic liquid and at least one lithium salt; A mixture of at least one aprotic solvent, at least one ionic liquid, and at least one lithium salt; Polymers that possess ion conductivity through the addition of at least one lithium salt; and Polymers that possess ion conductivity by adding liquid electrolytes to the polymer phase or to the mesoporous structure.

[0154] The use of conductive adhesives or conductive deposits formed by melt gel deposition can protect the metal substrate from corrosion. In this case, a first substrate and / or a second substrate made of less precious metal than those mentioned above, especially aluminum and copper, can be used.

[0155] The RTIL used is a combination of cationic and anionic groups. The cation is preferably selected from the group consisting of the following cationic compounds and families of cationic compounds: imidazolium (e.g., cationic 1-pentyl-3-methylimidazolium, abbreviated PMIM), ammonium, pyrrolidinum, and / or the anion is preferably selected from the group consisting of the following anionic compounds and families of anionic compounds: bis(trifluoromethanesulfonyl)imine, bis(trifluoromethanesulfonyl)imine, trifluoromethanesulfonate, tetrafluoroborate, hexafluorophosphate, 4,5-dicyano-2-(trifluoromethyl)imidazolium (abbreviated TDI), bis(oxalyl)borate (abbreviated BOB), oxalyl difluoroborate (abbreviated DFOB), bis(mandelato)borate (abbreviated BMB), and bis(perfluoropinacolato)borate (abbreviated BFPB).

[0156] As discussed in detail in the next section, in the second embodiment of this method, after step (h) and in step (i), the battery is immersed in an electrolyte, preferably a lithium-ion carrier phase, selected from the group consisting of: An electrolyte consisting of at least one aprotic solvent and at least one lithium salt; An electrolyte consisting of at least one ionic liquid and at least one lithium salt; A mixture of at least one aprotic solvent, at least one ionic liquid, and at least one lithium salt; Polymers that possess ion conductivity through the addition of at least one lithium salt; and Polymers that possess ion conductivity by adding liquid electrolytes to the polymer phase or to the mesoporous structure.

[0157] More preferably, the electrolytes are selected from the following groups: An electrolyte containing N-butyl-N-methylpyrrolidinium 4,5-dicyano-2-(trifluoromethyl)imidazole (Pyr 14TDI) and a lithium salt of the LiTDI type. An electrolyte containing 1-methyl-3-propylimidazolium 4,5-dicyano-2-(trifluoro-methyl)imidazolide (PMIM-TDI) and lithium 4,5-dicyano-2-(trifluoro-methyl)imidazolide (LiTDI).

[0158] The inorganic material E must be an electrically insulating material. Oxides such as Al₂O₃, ZrO₂, and SiO₂ can be used, as well as phosphates or borates. The nanoparticles of this material E form a mesoporous electrolyte separator layer.

[0159] 6. Immersed in electrolyte to form a battery

[0160] After assembling the stacked layers used to form the battery, hot pressing is performed, and the resulting assembly must be impregnated with an electrolyte to form the battery. The electrolyte must contain a lithium-ion carrier phase, as previously described. Impregnation can be performed at different steps in this method. Impregnation, especially with a liquid electrolyte, can be performed specifically on stacked or hot-pressed batteries (i.e., after battery assembly). Impregnation, especially with a liquid electrolyte, can also be performed after encapsulation, starting from the cut edge.

[0161] The lithium-ion support phase can be an organic liquid containing lithium salts. Alternatively, the lithium-ion support phase can be an ionic liquid (or a mixture of multiple ionic liquids) containing lithium salts, which can be diluted with an organic solvent or a mixture of organic solvents containing lithium salts, which may differ from the latter or the mixture dissolved in the ionic liquid. The lithium-ion support phase can comprise a mixture of multiple ionic liquids. Ionic liquids that are liquid at ambient temperature (RTIL = Room Temperature Ionic Liquid) can be used.

[0162] Typically, the cation of this ionic liquid is preferably selected from the following cation compounds and the group consisting of cation compounds and cation families: imidazolium (e.g., cation 1-pentyl-3-methylimidazolium, abbreviated PMIM), ammonium, pyrrolidone, and / or the anion of this ionic liquid is preferably selected from the following anionic compounds and the group consisting of cation compounds and anionic families: bis(trifluoromethanesulfonyl)imine, bis(trifluoromethanesulfonyl)imine, trifluoromethanesulfonate, tetrafluoroborate, hexafluorophosphate, 4,5-dicyano-2-(trifluoromethyl)imidazolium (abbreviated TDI), bis(oxalyl)borate (abbreviated BOB), oxalyl difluoroborate (abbreviated DFOB), bis(mandelato)borate (abbreviated BMB), and bis(perfluoropinacolato)borate (abbreviated BFPB).

[0163] The composition of the impregnating electrolyte and the concentration of its lithium salt can be adjusted according to the requirements of the battery's intended application in terms of temperature, power, etc.

[0164] Therefore, for example, for batteries designed to operate at high temperatures, it is preferable to use RTIL-based electrolytes of the Pyr 14FSI or Pyr 14TFSI type with LiFSI and / or LiTFSI and / or LiTDI (e.g., lithium salts). High-temperature resistant solvents, such as GBL, can be added up to less than 50%.

[0165] Additives can also be added to these formulations to reduce parasitic reactions on the electrode surface and / or on the current collector surface.

[0166] Advantageously, the lithium-ion support phase comprises at least one ionic liquid, preferably at least one ionic liquid at ambient temperature, such as PYR 14TFSI, which may be selectively diluted in at least one solvent, such as γ-butyrolactone.

[0167] The lithium-ion support phase may comprise, for example, LiPF6 or LiBF4 dissolved in an ionic liquid containing a lithium salt or an aprotic solvent. Ionic liquids, soluble in suitable solvents and / or mixed with organic electrolytes, may also be used. For example, LiPF6 dissolved in EC / DMC can be mixed at 50% by mass with a lithium-containing ionic liquid of the LiTFSI:PYR 14TFSI type (molar ratio 1:9). Mixtures of ionic liquids that operate at low temperatures can also be prepared, such as the mixture LiTFSI:PYR 13FSI:PYR 14TFSI (molar ratio 2:9:9).

[0168] EC is a common abbreviation for ethyl carbonate (CAS: 96-49-1). DMC is a common abbreviation for dimethyl carbonate (CAS: 616-38-6). LITFSI is a common abbreviation for lithium bis(trifluoromethanesulfonyl)imide (CAS: 90076-65-6). PYR 13FSI is a common abbreviation for N-propyl-N-methylpyrrolidinium bis(fluorosulfonyl)imide. PYR 14TFSI is a common abbreviation for 1-butyl-1-methylpyrrolidinium bis(trifluoromethanesulfonyl)imide.

[0169] The lithium-ion carrier phase can be an electrolyte solution containing an ionic liquid. The ionic liquid is formed by the combination of cations and anions, and the anion and cation are selected to ensure the ionic liquid remains liquid within the battery's operating temperature range. Ionic liquids offer advantages such as high thermal stability, low flammability, non-volatility, low toxicity, and good wettability to ceramics, making them suitable as electrode materials. Surprisingly, the mass percentage of the ionic liquid in the lithium-ion carrier phase can be greater than 50%, preferably greater than 60%, and more preferably greater than 70%, which is the opposite of conventional lithium-ion batteries, where the mass percentage of the ionic liquid in the electrolyte must be less than 50% by mass to maintain high capacity and voltage and good cycle stability during discharge. As disclosed in patent application US 2010 / 209783A1, in conventional batteries, a mass percentage greater than 50% by mass reduces battery capacity. This can be explained by the presence of polymer binders in the electrolyte of conventional batteries; these binders are slightly wetted by the ionic liquid, resulting in poor ionic conductivity in the lithium-ion carrier phase, thus causing a decrease in battery capacity.

[0170] PYR 14TFSI and LiTFSI can be used, and their abbreviations are defined as follows.

[0171] Advantageously, the ionic liquid can be a combination of cations of the type 1-ethyl-3-methylimidazolium (also known as EMI+ or EMIM+) and / or n-propyl-n-methylpyrrolidinium (also known as PYR 13+) and / or n-butyl-n-methylpyrrolidinium (also known as PYR 14+) with bis(trifluoromethanesulfonyl)imine (TFSI-) anions and / or bis(fluorosulfonyl)imine (FSI-). In an advantageous embodiment, the liquid electrolyte comprises at least 50% by mass of the ionic liquid, preferably Pyr 14TFSI.

[0172] Other cations that can be used in these ionic liquids include PMIM+. Other anions that can be used in these ionic liquids include BF4-, PF6-, BOB-, DFOB-, BMB-, and BPFPB-. To form an electrolyte, lithium salts such as LiTFSI can be dissolved in the ionic liquid as a solvent or in a solvent such as γ-butyrolactone. γ-Butyrolactone prevents the crystallization of the ionic liquid, resulting in a wider operating temperature range, especially at low temperatures. Advantageously, when the porous cathode contains lithium phosphate, the lithium ion support phase contains a solid electrolyte, such as LiBH4 or a mixture of LiBH4 and one or more compounds selected from LiCl, LiI, and LiBr. LiBH4 is a good conductor of lithium and has a low melting point, making it easy to impregnate in porous electrodes, especially by dipping. Due to its extreme reducing properties, LiBH4 is not widely used as an electrolyte. Applying a protective film to the surface of the porous lithium phosphate electrode can prevent the cathode material from being reduced by LiBH4 and avoid its degradation.

[0173] As mentioned above, a variety of ionic liquids can be used, especially Pyr 14TFSI-LiTFSI and EMIM-TFSI. The latter is more fluid than Pyr 14-TFSI. The main difference between these two ionic liquids lies in the potential range of their usable stability. EMIM-TFSI is stable in the range of 1 V to 4.7 V, while Pyr 14-TFSI is stable in the range of 0 V to 5.0 V, therefore Pyr 14-TFSI is preferred, despite its lower fluidity.

[0174] However, TFSI-type lithium salts tend to corrode substrates. Therefore, in ionic liquids and related salts, when the cathode operates at values ​​greater than 4.3 V, LiTDI is preferred over LiTFSI as the anionic group for the ionic liquid and / or lithium salt. It has been observed that simply adding LiTDI-type salts to LiTFSI-type salts reduces the corrosive effect of ionic liquids compared to metallic substrates. LiTFSI contains sulfur, which readily corrodes substrates, especially at high temperatures. LiTDI does not corrode substrates. TFSI can be used with substrates coated with a protective layer or with substrates made of materials more resistant to TFSI corrosion, such as Mo, W, Cr, Ti, and Ta.

[0175] It is generally advantageous that the lithium-ion support phase contains a solvent with a mass percentage between 10% and 40%, preferably between 30% and 40%, and more preferably between 30% and 40% of γ-butyrolactone, ethylene glycol dimethyl ether (glyme), or PC.

[0176] In an advantageous embodiment, the lithium-ion carrier phase comprises at least 50% by mass of an ionic liquid and less than 50% by mass of a solvent, which limits the safety and ignition risk in the event of battery failure containing such a lithium-ion carrier phase.

[0177] Advantageously, the lithium-ion support phase comprises: The lithium salt is selected from the group consisting of LiTFSI, LiFSI, LiBOB, LiDFOB, LiBMB, LiBPFPB and LiTDI. The concentration of the lithium salt is preferably between 0.5 mol / L and 4 mol / L. The inventors have found that using an electrolyte with a sufficiently high concentration of lithium salt is beneficial for very fast charging performance. The solvent or a mixture of solvents containing less than 40%, preferably less than or equal to 20%, may be, for example, γ-butyrolactone, PC, or ethylene glycol dimethyl ether; Optional additives, such as vitamin C, can be used to stabilize the interface and limit parasitic reactions.

[0178] In another embodiment, the lithium-ion support phase comprises: Solvents comprising 30% to 40% by mass, preferably γ-butyrolactone, PC, or ethylene glycol dimethyl ether, and... At least one ionic liquid, greater than 50%, preferably greater than 50% PYR 14TFSI.

[0179] As an example, the lithium-ion support phase may be an electrolyte solution containing PYR 14TFSI, LiTFSI and γ-butyrolactone, preferably an electrolyte solution containing about 90% PYR 14TFSI, 0.7 M LiTFSI, 2% LiTDI and 10% γ-butyrolactone by mass.

[0180] 7. Description of Advantageous Embodiments

[0181] The following describes several embodiments of the battery according to the present invention.

[0182] Typically, in this invention, the electrodes can be mesoporous. They can be thick (typically between about ten micrometers and hundreds of micrometers), and more specifically, their thickness can be greater than 10 µm. They can be prepared by depositing aggregates of nanoparticles. These aggregates can have polydisperse sizes and / or two different sizes (bimodal granulometry). In the finished state, these electrodes do not contain any binders (they may contain binders during the deposition of nanoparticle suspensions or pastes, but these binders are removed during calcination heat treatment). They can be partially sintered, that is, the primary nanoparticles, after thermomechanical consolidation, will fuse together by a "neck-down" phenomenon (known to those skilled in the art, as seen, for example, in "Particulate Composites" published by RM German in Springer International Publishing 2016, pp. 26 / 27) to form a continuous three-dimensional mesoporous network.

[0183] The mesopore porosity of the porous anode according to the invention is less than 50%, preferably between 20% and 45%, more preferably between 25% and 40%, and about 35% is suitable. Advantageously, a nanolayer of an electronic conductor (e.g., carbon) is deposited on the surface of the mesopores.

[0184] According to the present invention, these mesoporous electrodes are coated with a layer of nanometer thickness (typically between about 0.8 nm and 10 nm) extending across the entire surface. Here, the surface is not the geometric surface of the layer, but rather the entire surface of the mesopores, and the coating is applied within the pores. The coating may be a conductive carbon coating.

[0185] After the conductive layer is coated, the electrode is immersed in a lithium-ion conductive phase. This phase can be liquid or solid. If it is solid, it can be an organic material or a mineral.

[0186] This electrode is bonded and sintered onto a high-temperature heat-treatable substrate, which can be made of, for example, W, Mo, Cr, Ti, and all alloys containing at least one of these elements. Stainless steel is suitable. It should be noted that in the case of preparing a self-supporting electrode plate, the limitation on the oxidation resistance of the substrate or current collector at the electrode's heat treatment temperature no longer exists, since the electrode is not yet in contact with its current collector during heat treatment.

[0187] More specifically, the anode can be a TiNb₂O₇ anode (abbreviated as "TNO"), but the following description also covers other active materials for the anode.

[0188] More specifically, a TiNb₂O₇ anode with a mesopore volume of approximately 35% can be used. The capacitance of this anode is approximately 230 mAh / g.

[0189] Using these anodes, specifically the TiNb₂O₇ anode with a mesopore volume of approximately 35% as described above, lithium-ion batteries can be manufactured. To enable those skilled in the art to practice the invention, five embodiments are described below, which do not limit the scope of the invention.

[0190] In the first embodiment, an attempt is made to increase the energy of the battery by selecting a cathode that operates at a high voltage.

[0191] The cathode current collector is a sheet of Mo, W, Ta, Ti, Al, stainless steel, Cr, or any alloy containing at least one of these elements, typically with a thickness between 5 µm and 20 µm. The cathode is made of LiCoPO4 with a mesopore volume of approximately 35%. The cathode is approximately 90 µm thick, with a nanolayer of an electronic conductor (in this case, carbon) deposited on the surface of the mesopores. The capacitance of this cathode is approximately 145 mAh / g.

[0192] The separator is a Li3PO4 layer with a thickness of about 6 µm and a mesopore volume of about 50%.

[0193] The anode current collector is a sheet of Mo, W, Ta, Ti, Cu, Cr, Ni, Al, stainless steel, or any alloy containing at least one of these elements, typically with a thickness between 5 µm and 20 µm. In a second embodiment of the invention, the anode is initially deposited (or extruded) onto an intermediate substrate, and an aluminum electrode, for example, may also be used. The thickness of the TiNb₂O₇ anode, having a mesopore volume of about 35%, is about 50 µm.

[0194] In any case, more specifically in the second embodiment of the invention (where the anode is made in the form of a plate), the surface of the current collector designed to contact the electrode may be coated with a conductive coating, which, in the case of the second embodiment of the invention, is also used to form a bond.

[0195] The battery is immersed in an RTIL-type ionic liquid (Room Temperature Ionic Liquid) formed by a mixture of Pyr 14TFSI (1-butyl-1-methylpyrrolidone bis(trifluoromethanesulfonyl)imine, CAS 223437-11-4) and 20% GBL and LiTFSI (lithium bis(trifluoromethanesulfonyl)imine, CAS 90076-65-6, concentration 0.7M).

[0196] The following mixture can also be used: LiTFSI 0.7M + Pyr 14TFSI + 10% GBL + 2% LiTDI.

[0197] This type of battery achieves a volumetric capacitance density of approximately 200 mAh / cm³ and a volumetric energy density of approximately 610 mWh / cm³. It can provide continuous power at approximately 50°C. It can operate over a very wide temperature range, typically between approximately -40°C and +60°C. There is no risk of thermal runaway.

[0198] One of the drawbacks of this battery is the high cost of the cathode material due to its high cobalt content.

[0199] In the second embodiment, the LiCoPO4 cathode material is replaced by another high-voltage cathode material that does not contain cobalt, namely a spinel material, LiMn1.5Ni0.5O4. It contains manganese, therefore the resistance of this battery is less restricted at high temperatures compared to the first embodiment.

[0200] The LiMn1.5Ni0.5O4 cathode has a thickness of approximately 90 µm, a mesopore volume of approximately 35%, and is deposited with a carbon nanolayer. The size of this cathode is equivalent to a capacity of approximately 120 mAh / g.

[0201] The separator, anode, cathode, and anode current collector, as well as the ionic liquid used for impregnation in the battery, are the same as in the first embodiment.

[0202] This battery achieves a volumetric capacitance density of 210 mAh / cm³ and a volumetric energy density of 625 mWh / cm³. It can provide a continuous current greater than 50 C. It operates over a very wide temperature range, typically between approximately -40°C and +60°C. There is no risk of thermal runaway. These batteries are compatible with fast charging and can be recharged in less than 5 minutes without the risk of lithium deposit formation.

[0203] In the third embodiment, a cathode that operates at low voltage is used.

[0204] The cathode is made of Li 1.2Ni 0.13Mn 0.54Co 0.13O 2 with a thickness of about 90 µm, a mesopore volume of about 35%, and a carbon nanolayer deposited on it. The size of this cathode is equivalent to a capacity of about 200 mAh / g.

[0205] The separator is a layer of Li3PO4 with a thickness of about 6 µm and a mesopore volume of about 50%.

[0206] The anode current collector is a sheet of Cu, Ni, W, Ta, Al, Cr, stainless steel, Ti or Mo, or any alloy containing at least one of these elements, with a thickness typically between 5 µm and 20 µm. A TiNb₂O₇ anode with a mesopore volume of approximately 35% has a thickness of approximately 80 µm, with a carbon nanolayer deposited on the mesopore surface.

[0207] The battery is immersed in an RTIL-type ionic liquid, which consists of a mixture of LiTDI and LiTFSI, more precisely, a mixture of Pyr 14TFSI, 0.7M LiTFSI, and 2% LiTDI.

[0208] This battery achieves a volumetric capacitance density of 285 mAh / cm³ and a volumetric energy density of 720 mWh / cm³. It can provide a continuous current greater than 50 C. It operates over a very wide temperature range, typically between approximately -40°C and +70°C. There is no risk of thermal runaway. These batteries are compatible with fast charging and can be recharged in less than 5 minutes without the risk of lithium deposit formation.

[0209] It should be noted that when the cathode surface capacitance is lower than the anode surface capacitance, this cell can operate over an extended temperature range (up to approximately +85°C).

[0210] The fourth embodiment relates to a high-capacity microcell having a cathode that operates at low voltage.

[0211] The cathode current collector is a sheet of Mo, W, Ta, Ti, Al, stainless steel, Cr, or any alloy containing at least one of these elements, with a thickness typically between 5 µm and 20 µm. If the nanoparticles used to make the cathode are fully crystalline, or if the current collector is bonded to the electrode after sintering in the case where the electrode is made into an electrode plate, aluminum sheet can be used.

[0212] The cathode is made of Li 1.2Ni 0.13Mn 0.54Co 0.13O 2 with a thickness of about 16 µm, a mesopore volume of about 35%, and a carbon nanolayer deposited on it. The cathode has a capacity of about 200 mAh / g.

[0213] The separator is a Li3PO4 layer with a thickness of about 6 µm and a mesopore volume of about 50%.

[0214] The anode current collector is a sheet of Cu, Ni, Al, or Mo, with a thickness typically between 5 µm and 20 µm. A TiNb₂O₇ anode with a mesopore volume of approximately 35% has a thickness of approximately 14 µm, with a carbon nanolayer deposited on the mesopore surface.

[0215] The battery is immersed in an RTIL-type ionic liquid, which consists of Pyr 14TFSI, 0.7M LiTFSI, and 2% LiTDI.

[0216] This microbattery achieves a volumetric capacitance density of 215 mAh / cm³ and a volumetric energy density of 535 mWh / cm³. It can provide a continuous current greater than 50 C. It operates over a very wide temperature range, typically between approximately -40°C and +70°C. There is no risk of thermal runaway. These batteries are also compatible with fast recharging. As mentioned above, when the electrode dimensions are adjusted so that the cathode surface capacitance is lower than the anode surface capacitance, the operating temperature range can be extended to approximately +85°C.

[0217] These battery cells and batteries exhibit excellent performance at low temperatures. They can operate below the crystallization temperature of liquid electrolytes. When impregnated with polymers, the conductivity of the polymers can be improved over a wide temperature range.

[0218] An advantageous battery according to the invention has a cathode current collector made of a material selected from the group consisting of Mo, Ti, W, Ta, Cr, Al, alloys based on the above elements, and stainless steel. It also has a cathode with a pore volume between 30% and 40%, made of NMC, preferably NMC 433, with a conductive carbon layer deposited in the pores. Its separator is a mesoporous layer of Li3PO4, preferably with a thickness between 6 µm and 8 µm. The anode is a layer of TiNb2O7, preferably doped with halides and / or cerium and / or germanium and / or lanthanum and / or copper, the layer being immersed in a liquid electrolyte containing lithium salt. Its anode current collector is selected from the group consisting of Mo, Cu, Ni, alloys based on the aforementioned elements, and stainless steel. Aluminum can also be used. Other separator materials can be used.

[0219] The batteries according to the present invention can be manufactured with very different power ratings. In particular, by means of the method according to the present invention, lithium-ion batteries with a capacity of no more than 1 mAh can be manufactured, which have excellent high power and open up many applications in electronic boards, electronic devices, and especially medical devices. These batteries can operate over a very wide temperature range and can be recharged in less than 15 minutes. Batteries with a capacity of no more than 1 mAh are referred to herein as "micro batteries".

[0220] Example

[0221] In addition to the specific embodiments described above, further examples are provided herein to enable those skilled in the art to reproduce the invention. These examples do not limit the invention.

[0222] Example 1: Synthesis of TNO nanopowder for the anode according to the present invention

[0223] The agglomerates of Ti 0.95Ge 0.05Nb 2O 7 nanoparticles were prepared by synthesizing the following alkoxides: (i)Ge(OC₂H₅)₄, molecular weight 252.88 g / mol, density 1.14 g / cm³; (ii) Ti(OC₂H₅)₄, molecular weight 228.11 g / mol, density 1.09 g / cm³; (iii) Nb(OC 2H 5) 4, molecular weight 318.21 g / mol, density 1.268 g / cm 3.

[0224] In the first step, citric acid is dissolved in ethylene glycol by heating to 80°C. Simultaneously, a mixture of ethoxide is prepared in a glove box, taking into account the stoichiometry of the target component.

[0225] In the second step, the mixture of alkoxides was introduced into the citric acid / ethylene glycol solution at room temperature under vigorous stirring. The reaction mixture was stirred at 80°C for 12 hours, causing the solution to gel.

[0226] The gel extraction was then placed in an aluminum crucible. The crucible was placed in a heating chamber at 250°C for 12 hours. This heating step removes excess ethylene glycol and activates the esterification reaction. The product was then calcined at 600°C for 1 hour to remove most of the organic material.

[0227] A second heat treatment was then performed at 800°C. This resulted in aggregates of nanoparticles (with a basic size of 40 nm) crystallized in space group I2 / m JCPDS: 39-1407. These were pure monoclinic crystals.

[0228] Figure 1 shows the electrochemical properties of the anode prepared according to this example.

[0229] Example 2: Manufacturing of the perforated anode plate according to the present invention

[0230] A slurry composed of TNO nanoparticle aggregates was prepared. These aggregates were approximately 100 nm in size and consisted of primary particles with a diameter of 15 nm. These nanoparticle aggregates were integrated into a slurry having the following composition (by mass percentage): 20% TNO nanoparticle aggregates, 36% 2-butanol and 24% ethanol as solvents, 3% phosphate ester as a dispersant, 8.5% dibutyl phthalate as a plasticizer, and 8.5% methacrylic acid resin as a binder.

[0231] The slurry was cast into strips, then cut into plates and dried. These plates were then annealed in air at 600°C for 1 hour to obtain a mesoporous ceramic plate as an electrode. The plate was then immersed in a glucose solution and annealed at 400°C under N2 to nano-coat the entire mesoporous surface of the electrode with conductive carbon.

[0232] none

Claims

1. A method for manufacturing a porous anode for a battery, the porous anode comprising a porous layer having a porosity between 25% and 50% by volume and pores with an average diameter of less than 50 nanometers, the method comprising the steps of: (a) providing a substrate and a colloidal suspension or paste in the form of an aggregate or a dispersion of at least one anode active material A, wherein the average diameter D50 of each of the monodisperse primary nanoparticles is between 2 nanometers and 100 nanometers, wherein the colloidal suspension or the paste The system comprises a liquid component, wherein the active material A of the at least one anode is selected from a mixed oxide of niobium and titanium, represented as follows: TiNb2O7-δ, Ti1-xM1xNb2-yM2yO7-δ, LiwTi1-xM1xNb2-yM2yO7, wherein M1 and M2 are each selected from at least one element selected from the group consisting of Nb, V, Ta, Fe, Co, Ti, Bi, Sb, As, P, Cr, Mo, W, B, Na, Mg, Ca, Ba, Pb, Al, Zr, Si, Sr, K, Cs, and Sn, wherein M1 and M2 are the same or different from each other, wherein 0 ≤ w ≤ 5, 0 ≤ x < 1, 0 ≤ y < 2 and 0 ≤ δ ≤ 0.3; Ti1-xM1xNb2-yM2yO7-zM3z, LiwTi1-xM1xNb2-yM2yO7-zM3z, where M1 and M2 are each selected from the group consisting of Nb, V, Ta, Fe, Co, Ti, Bi, Sb, As, P, Cr, Mo, W, B, Na, Mg, Ca, Ba, Pb, Al, Zr, Si, Sr, K, Cs and Sn, M1 and M2 are the same or different from each other, and M3 is at least one halogen, where 0 ≤ w ≤ 5, 0 ≤ x < 1, 0 ≤ y < 2 and z ≤ 0.3; TiNb2O7-zM3z, LiwTiNb2O7-zM3z, wherein M3 is at least one halogen selected from F, Cl, Br, I or mixtures thereof, and 0 ≤ w ≤ 5 and 0 < z ≤ 0.3; Ti1-xGexNb2-yM1yO7-z, LiwTi1-xGexNb2-yM1yO7-z, Ti1-xLaxNb2-yM1yO7-z, LiwTi1-xLaxNb2-yM1yO7-z, Ti1-xCexNb2-yM1yO7-z, LiwTi1-xCexNb2-yM1yO7-z, where M1 is at least one element selected from the group consisting of Nb, V, Ta, Fe, Co, Ti, Bi, Sb, As, P, Cr, Mo, W, B, Na, Mg, Ca, Ba, Pb, Al, Zr, Si, Sr, K, Cs, Ce, and Sn, where 0 ≤ w ≤ 5, 0 ≤ x < 1, 0 ≤ y < 2, and z < 1; Ti1-xGexNb2-yM1yO7-zM2z, LiwTi1-xGexNb2-yM1yO7-zM2z, Ti1-xLaxNb2-yM1yO7-zM2z , LiwTi1-xLaxNb2-yM1yO7-zM2z, Ti1-xCuxNb2-yM1yO7-zM2z, LiwTi1-xCuxNb2-yM1yO7-zM 2z, Ti1-xCexNb2-yM1yO7-zM2z, LiwTi1-xCexNb2-yM1yO7-zM2z, wherein M1 and M2 are each selected from the group consisting of Nb, V, Ta, Fe, Co, Ti, Bi, Sb, As, P, Cr, Mo, W, B, Na, Mg, Ca, Ba, Pb, Al, Zr, Si, Sr, K, Cs, and Sn; 0 ≤ w ≤ 5, 0 ≤ x < 1, 0 ≤ y < 2 and z ≤ 0.3; (b) depositing a layer from the colloidal suspension or paste provided in step (a) on at least one surface of the substrate by means of a method selected from the group consisting of: electrophoresis, extrusion, printing and coating; and (c) drying the layer obtained in step (b) and consolidating it by at least one of pressure and heating to obtain the porous layer.

2. The method as claimed in claim 1, wherein the method further comprises step (d): (d) depositing a coating of a conductive material on and within the pores of the porous layer, the conductive material being selected from carbon or a conductive oxide material, the conductive oxide material being selected from: tin oxide (SnO2), zinc oxide (ZnO), indium oxide (In2O3), gallium oxide (Ga2O3), mixtures of two of these oxides, mixtures of three of these oxides, or mixtures of four of these oxides, based on a zinc oxide doped oxide, and doped with gallium (Ga), aluminum (Al), boron (B), beryllium (Be), chromium (Cr), cerium (Ce), titanium (Ti), indium (In), cobalt (Co), nickel (Ni), copper ( At least one of Cu, manganese (Mn) and germanium (Ge), based on an indium oxide doped oxide, doped with at least one of tin (Sn), gallium (Ga), chromium (Cr), cerium (Ce), titanium (Ti), indium (In), cobalt (Co), nickel (Ni), copper (Cu), manganese (Mn) and germanium (Ge), doped with tin oxide, doped with at least one of arsenic (As), fluorine (F), nitrogen (N), niobium (Nb), phosphorus (P), antimony (Sb), aluminum (Al), titanium (Ti), gallium (Ga), chromium (Cr), cerium (Ce), indium (In), cobalt (Co), nickel (Ni), copper (Cu), manganese (Mn) and germanium (Ge).

3. The method as described in claim 2, wherein the coating of the conductive material is deposited by means of atomic layer deposition or by immersion in a liquid phase containing a precursor of the conductive material and then converting the precursor into the conductive material.

4. The method as described in claim 3, wherein the precursor is a carbon-rich compound and is transformed into the conductive material by pyrolysis in an inert environment, or wherein the precursor is selected from an organic salt containing one or more metal elements capable of forming a conductive oxide after heat treatment and is transformed into the conductive material by heat treatment in air or an oxidizing environment.

5. The method as described in claim 4, wherein the organic salt is selected from alkoxides that can be heat-treated in air or an oxidizing environment to form at least one metal element of the conductive oxide, oxalates that can be heat-treated in air or an oxidizing environment to form at least one metal element of the conductive oxide, and acetates that can be heat-treated in air or an oxidizing environment to form at least one metal element of the conductive oxide.

6. The method as described in claim 4, wherein the metal element is selected from tin, zinc, indium, gallium, or a mixture of two, three, or four of these elements.

7. The method as described in any one of claims 1 to 6, wherein the monodisperse primary nanoparticles are in the form of aggregates or clusters, and the average diameter D50 of the aggregates or clusters is between 50 nanometers and 300 nanometers.

8. The method as described in any one of claims 1 to 6, wherein the specific surface area of ​​the porous layer obtained by step (c) is between 10 square meters / gram and 500 square meters / gram.

9. The method as described in any one of claims 1 to 6, wherein the thickness of the porous layer obtained by step (c) is between 1 micrometer and 150 micrometers.

10. The method of any one of claims 1 to 6, wherein the substrate is an intermediate substrate, and in step (c) the layer is separated from the intermediate substrate after drying to form a porous anode plate.

11. A porous anode for a lithium-ion battery, comprising a porous layer having a porosity between 25% and 50% by volume, wherein the porous layer comprises: pores with an average diameter of less than 50 nanometers, a porous mesh of material A, and a coating of a conductive material on and within the pores forming the porous mesh, wherein material A is selected from a mixed oxide of niobium and titanium, represented as follows: TiNb2O7-δ, Ti1-xM1xNb2-yM2yO7-δ, LiwTi1-xM1xNb2-yM2yO7, wherein M1 and M2 are each selected from at least one element selected from the group consisting of Nb, V, Ta, Fe, Co, Ti, Bi, Sb, As, P, Cr, Mo, W, B, Na, Mg, Ca, Ba, Pb, Al, Zr, Si, Sr, K, Cs, and Sn, wherein M1 and M2 are the same or different from each other, wherein 0 ≤ w ≤ 5, 0 ≤ x < 1, 0 ≤ y < 2 and 0 ≤ δ ≤ 0.3; Ti1-xM1xNb2-yM2yO7-zM3z, LiwTi1-xM1xNb2-yM2yO7-zM3z, where M1 and M2 are each selected from the group consisting of Nb, V, Ta, Fe, Co, Ti, Bi, Sb, As, P, Cr, Mo, W, B, Na, Mg, Ca, Ba, Pb, Al, Zr, Si, Sr, K, Cs and Sn, M1 and M2 are the same or different from each other, and M3 is at least one halogen, where 0 ≤ w ≤ 5, 0 ≤ x < 1, 0 ≤ y < 2 and z ≤ 0.3; TiNb2O7-zM3z, LiwTiNb2O7-zM3z, wherein M3 is at least one halogen selected from F, Cl, Br, I or a mixture thereof, and 0 ≤ w ≤ 1 and 0 < z ≤ 0.3; Ti1-xGexNb2-yM1yO7-z, LiwTi1-xGexNb2-yM1yO7-z, Ti1-xCexNb2-yM1yO7-z, LiwTi1-xCexNb2-yM1yO7-z, where M1 is at least one element selected from the group consisting of Nb, V, Ta, Fe, Co, Ti, Bi, Sb, As, P, Cr, Mo, W, B, Na, Mg, Ca, Ba, Pb, Al, Zr, Si, Sr, K, Cs, Ce, and Sn, where 0 ≤ w ≤ 5, 0 ≤ x < 1, 0 ≤ y < 2, and z < 0. 1; Ti1-xGexNb2-yM1yO7-zM2z, LiwTi1-xGexNb2-yM1yO7-zM2z, Ti1-xLaxNb2-yM1yO7-zM2z , LiwTi1-xLaxNb2-yM1yO7-zM2z, Ti1-xCuxNb2-yM1yO7-zM2z, LiwTi1-xCuxNb2-yM1yO7-zM 2z, Ti1-xCexNb2-yM1yO7-zM2z, LiwTi1-xCexNb2-yM1yO7-zM2z, wherein M1 and M2 are each selected from the group consisting of Nb, V, Ta, Fe, Co, Ti, Bi, Sb, As, P, Cr, Mo, W, B, Na, Mg, Ca, Ba, Pb, Al, Zr, Si, Sr, K, Cs, and Sn; 0 ≤ w ≤ 5, 0 ≤ x < 1, 0 ≤ y < 2, and z ≤ 0.3; the porous anode can be obtained by the method described in any one of claims 1 to 9.

12. The porous anode as claimed in claim 11, wherein the conductive material is selected from carbon or a conductive oxide material selected from: tin oxide (SnO2), zinc oxide (ZnO), indium oxide (In2O3), gallium oxide (Ga2O3), mixtures of two of these oxides, mixtures of three of these oxides, or mixtures of four of these oxides, based on a zinc oxide doped oxide, and doped with gallium (Ga), aluminum (Al), boron (B), beryllium (Be), chromium (Cr), cerium (Ce), titanium (Ti), indium (In), cobalt (Co), nickel (Ni), copper (Cu), manganese (Mn). At least one of tin (Sn), gallium (Ga), chromium (Cr), cerium (Ce), titanium (Ti), indium (In), cobalt (Co), nickel (Ni), copper (Cu), manganese (Mn), and germanium (Ge), based on an indium oxide doped oxide, and doped with at least one of arsenic (As), fluorine (F), nitrogen (N), niobium (Nb), phosphorus (P), antimony (Sb), aluminum (Al), titanium (Ti), gallium (Ga), chromium (Cr), cerium (Ce), indium (In), cobalt (Co), nickel (Ni), copper (Cu), manganese (Mn), and germanium (Ge).

13. A method of manufacturing a battery, wherein the method comprises using the method described in any one of claims 1 to 10 or using a porous anode as described in claim 11.

14. A method of manufacturing a battery, wherein the battery comprises at least one porous anode as described in claim 11 or 12, at least one separator, and at least one porous cathode, the method comprising: (a) providing a first substrate, a second substrate, a first colloidal suspension or a paste, a second colloidal suspension, and a third colloidal suspension, wherein the first colloidal suspension or the paste comprises aggregates or clusters of a plurality of monodisperse primary nanoparticles of an active material A of at least one anode, wherein the average diameter D50 of each of the monodisperse primary nanoparticles is between 2 nm and 100 nm, and the average diameter D50 of the aggregates or clusters of the monodisperse primary nanoparticles is between 2 nm and 100 nm. 50 is between 50 nanometers and 300 nanometers, wherein the active material A of the at least one anode is selected from a mixed oxide of niobium and titanium, represented as follows: TiNb2O7-δ, Ti1-xM1xNb2-yM2yO7-δ, LiwTi1-xM1xNb2-yM2yO7, wherein M1 and M2 are each selected from at least one element selected from the group consisting of Nb, V, Ta, Fe, Co, Ti, Bi, Sb, As, P, Cr, Mo, W, B, Na, Mg, Ca, Ba, Pb, Al, Zr, Si, Sr, K, Cs, and Sn, wherein M1 and M2 are the same or different from each other, wherein 0 ≤ w ≤ 5, 0 ≤ x < 1, 0 ≤ y < 2 and 0 ≤ δ ≤ 0.3; Ti1-xM1xNb2-yM2yO7-zM3z, LiwTi1-xM1xNb2-yM2yO7-zM3z, where M1 and M2 are each selected from the group consisting of Nb, V, Ta, Fe, Co, Ti, Bi, Sb, As, P, Cr, Mo, W, B, Na, Mg, Ca, Ba, Pb, Al, Zr, Si, Sr, K, Cs and Sn, M1 and M2 are the same or different from each other, and M3 is at least one halogen, where 0 ≤ w ≤ 5, 0 ≤ x < 1, 0 ≤ y < 2 and z ≤ 0.3; TiNb2O7-zM3z, LiwTiNb2O7-zM3z, wherein M3 is at least one halogen selected from F, Cl, Br, I or mixtures thereof, and 0 ≤ w ≤ 5 and 0 < z ≤ 0.3; Ti1-xGexNb2-yM1yO7-zM2z, LiwTi1-xGexNb2-yM1yO7-zM2z, Ti1-xLaxNb2-yM1yO7-zM2z , LiwTi1-xLaxNb2-yM1yO7-zM2z, Ti1-xCuxNb2-yM1yO7-zM2z, LiwTi1-xCuxNb2-yM1yO7-zM 2z, Ti1-xCexNb2-yM1yO7-zM2z, LiwTi1-xCexNb2-yM1yO7-zM2z, where M1 and M2 are each selected from at least one element of the group consisting of Nb, V, Ta, Fe, Co, Ti, Bi, Sb, As, P, Cr, Mo, W, B, Na, Mg, Ca, Ba, Pb, Al, Zr, Si, Sr, K, Cs, and Sn; 0 ≤ w ≤ 5, 0 ≤ x < 1, 0 ≤ y < 2, and z ≤ 0.3; Ti1-xGexNb2-yM1yO7-z, LiwTi1-xGexNb2-yM1yO7-z, Ti1-xLaxNb2-yM1yO7-z, LiwTi1-xCexNb2-yM1yO7-z, where M1 is at least one element selected from the group consisting of Nb, V, Ta, Fe, Co, Ti, Bi, Sb, As, P, Cr, Mo, W, B, Na, Mg, Ca, Ba, Pb, Al, Zr, Si, Sr, K, Cs, Ce, and Sn, where 0 ≤ w ≤ 5, 0 ≤ x < 1, 0 ≤ y < 2, and z < 0. 1; wherein at least one of the first substrate and the second substrate is a substrate or an intermediate substrate capable of serving as a current collector; the second colloidal suspension comprises aggregates or clusters of multiple monodisperse primary nanoparticles of at least one cathode active material C, wherein the average diameter D50 of each of the monodisperse primary nanoparticles is between 2 nm and 100 nm, and the average diameter D50 of the aggregates or clusters of the monodisperse primary nanoparticles is between 50 nm and 300 nm; and the third colloidal suspension comprises multiple nanoparticles of at least one inorganic material E. (a) Aggregates or clusters of nanoparticles, wherein the average diameter D50 of each nanoparticle is between 2 nm and 100 nm, and the average diameter D50 of the aggregates or clusters of nanoparticles is between 50 nm and 300 nm; (b) depositing an anodic layer from the first colloidal suspension provided in step (a) on at least one side of the first substrate, and depositing a cathode layer from the second colloidal suspension provided in step (a) on at least one side of the second substrate, and performing the process by a method selected from the group consisting of: electrophoresis, extrusion, printing, and coating. (c) Drying the anode layer and the cathode layer obtained in step (b), and consolidating each layer by at least one of pressurization and heating to obtain a porous anode layer and a porous cathode layer respectively; (e) Depositing a porous inorganic layer from the third colloidal suspension provided in step (a) onto at least one of the porous anode and the porous cathode obtained in step (d), and performing the process by a technique selected from the group consisting of: electrophoresis, extrusion, printing methods and coating methods; (f) Drying the porous inorganic layer having the structure obtained in step (e) under an airflow at a temperature higher than that of the airflow. (g) Performing heat treatment at a temperature of 130°C; (d) continuously stacking the porous anode obtained in step (d) or (e) with the porous cathode obtained in step (e) face-to-face, wherein one of the resulting stacks includes at least one porous inorganic layer as obtained in step (e) forming the separator; and (h) hot-pressing the stack obtained in step (g) at a temperature between 120°C and 600°C to obtain the battery comprising at least one porous anode, at least one separator, and at least one porous cathode.

15. The method as described in claim 14, wherein the inorganic material E is an electrical insulator.

16. The method as described in claim 14 or 15, wherein the product obtained from step (h) is impregnated with an electrolyte selected from the group consisting of: an electrolyte comprising at least one aprotic solvent and at least one lithium salt; an electrolyte comprising at least one ionic liquid and at least one lithium salt; a mixture of at least one aprotic solvent, at least one ionic liquid and at least one lithium salt; a polymer having ionic conductivity by adding at least one lithium salt; and a polymer having ionic conductivity by adding a liquid electrolyte to the polymer phase or to the mesoporous structure.

17. The method as described in claim 14 or 15, wherein the active material C of the cathode is selected from the group consisting of: LiCoPO4; LiMn1.5Ni0.5O4; LiFexCo1-xPO4, where 0 < x < 1; LiNi1 / xCo1 / yMn1 / zO2, where x+y+z = 10; Li1.2Ni0.13Mn0.54Co0.13O2; LiMn1.5Ni0.5-xXxO4, where X is selected from Al, Fe, Cr, Co, Rh, Nd, Sc, Y, Lu, La, Ce, Pr, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, 0 < x < 0.1; LiNi0.8Co0.15Al0.05O2; Li2MPO4F, where M = Fe, Co, Ni or a mixture of these different elements; LiMPO4F, where M = V, Fe, T or a mixture of these different elements; LiMSO4F, where M = Fe, Co, Ni, Mn, Zn, Mg; LiCoO2.

18. The method as claimed in claim 14, wherein step (c) further comprises separating the anode layer and the cathode layer from their intermediate substrate before consolidating the layers by at least one of pressurization and heating to obtain a porous anode layer and a porous cathode layer, respectively.

19. The method as claimed in claim 14 further includes step (d) between steps (c) and (e), wherein a coating of a conductive material is deposited on and in the pores of at least one of the porous anode layer and the porous cathode layer to form the porous anode and the porous cathode.

20. The method as claimed in claim 14, wherein step (f) further comprises pressing the porous inorganic layer, which is separated from the intermediate substrate, onto a metal sheet that can serve as a current collector before heat treatment.

21. A lithium-ion battery obtained by the method described in any one of claims 13 to 20.

22. The lithium-ion battery as claimed in claim 21, wherein its electrolyte contains at least 50% by mass of an ionic liquid of Pyr14TFSI (CAS 223437-11-4).

23. The lithium-ion battery as claimed in claim 21 or 22, wherein its cathode current collector is made of a material selected from the group consisting of Mo, Ti, W, Ta, Cr, Al, alloys based on the aforementioned elements, and stainless steel; its cathode is made of NMC having a porous volume between 30% and 40%, and a conductive layer of carbon is deposited in the pores; its separator is a mesoporous layer of Li3PO4 with a thickness between 6 micrometers and 8 micrometers; its anode is a TiNb2O7-δ layer, 0 ≤ δ ≤ 0.3, doped with at least one of a halide and germanium, the layer being impregnated with a liquid electrolyte containing a lithium salt; and its anode current collector is made of the group consisting of Mo, Cu, Ni, alloys based on the aforementioned elements, and stainless steel.

24. The lithium-ion battery as described in claim 21 or 22, wherein the thickness of its electrodes is greater than 10 micrometers.

25. A lithium-ion battery as claimed in claim 21 or 22, wherein it comprises a porous anode as claimed in claim 10 or 11, or the porous anode can be obtained by the method described in any one of claims 1 to 9, wherein the mass capacity of the porous anode is greater than 200 mAh / g.

26. Use of a lithium-ion battery as described in any one of claims 21 to 24 at at least one of a temperature below -10°C and a temperature above 50°C.

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