Carbon Anode Material

Abstract

The present invention relates to a carbon-containing anode material capable of intercalating and deintercalating alkali metal ions. The present invention further relates to a process for preparing a carbon-containing anode material capable of intercalating and deintercalating alkali metal ions.

Description

[Technical field]

[0001] The present invention relates to certain novel carbon-containing anode materials, novel processes for producing such carbon-containing anode materials, anode electrodes containing such novel carbon-containing anode materials, and the use of such anode electrodes in energy storage devices such as, for example, batteries (particularly rechargeable batteries), electrochemical devices, and electrochromic devices. [Background technology]

[0002] Sodium-ion batteries are similar in many ways to the lithium-ion batteries commonly used today; they are both reusable secondary batteries that contain an anode (negative electrode), a cathode (positive electrode) and electrolyte materials, they both can store energy, and they both charge and discharge via similar reaction mechanisms. When charging a sodium-ion (or lithium-ion) battery, Na + (or Li + ) ions are extracted from the cathode and inserted into the anode, while charge-balancing electrons pass from the cathode through an external circuit containing the charger to the battery's anode. During discharge, the same process occurs in the opposite direction. Lithium-ion battery technology has attracted much attention in recent years, providing the preferred portable battery for most electronic devices currently in use; however, certain components of lithium-ion batteries, such as Li, Cu, Co and graphite, are not abundant, and the technology is considered too expensive for large-scale applications.In contrast, sodium-ion battery technology is still in its relatively early stages, but is considered advantageous; sodium is much more abundant than lithium, and is believed to provide a cheaper and more sustainable method of energy storage in the future, especially for large-scale applications such as energy storage in power grids.

[0003] Significant research progress has been made in developing cathode electrode materials with high charge storage capacity and rate capability for both lithium-ion and sodium-ion batteries. However, the development of new and more efficient anode electrode materials requires further attention.

[0004] Carbon in the form of graphite is the preferred anode material for lithium-ion batteries due to its high gravimetric and volumetric capacity; graphite electrodes achieve reversible capacities in excess of 360 mAh / g, matching the theoretical capacity of 372 mAh / g. An electrochemical reduction process introduces Li between the graphene layers. + However, graphite exhibits a much lower electrochemical activity towards sodium, and due to this, and the fact that sodium has a significantly larger atomic radius compared to lithium, intercalation between the graphene layers of the graphite anode is severely limited in sodium-ion cells.

[0005] On the other hand, anodes made using hard carbon materials (such as those described in PCT / GB2020 / 050872, U.S. Patent Application Publication No. 2002 / 0192553 A1, U.S. Patent Publication No. 9899665 B2, and U.S. Patent Application Publication No. 2018 / 0287153 A1) have been found to provide much more favorable results in sodium-ion cells.

[0006] Hard carbons have a disordered structure that overcomes many of the intercalation problems associated with sodium ions. The exact structure of hard carbon materials has yet to be elucidated, but hard carbons are generally described as non-graphitizable carbon materials that lack long-range crystalline order. Although hard carbons have layers, these are not neatly stacked over long distances, and hard carbons are microporous materials. Despite lacking a definable crystallographic structure, hard carbons exhibit isotropy at the macroscopic level. One of the reasons it is difficult to construct a universal structural model for hard carbons is that the short-range order, domain size, fraction of carbon layers, and micropore structure depend on the synthesis conditions, such as the carbon source, carbonization, and pyrolysis temperatures.

[0007] Furthermore, unlike graphite, which has a layered crystal structure in which carbon planes (graphene) are stacked, hard carbon has a turbostratic structure in which the carbon layer planes are stacked with a three-dimensional misalignment. Thus, heat treatment of hard carbon, even at high temperatures (e.g., 3000°C), does not result in a complete conversion of the turbostratic structure to a graphitic structure or the growth of graphite crystallites. Thus, hard carbon is structurally significantly different from graphite, and can be said to contain one or more non-graphitizable regions and one or more non-graphitizable regions.

[0008] Typical methods for producing hard carbon materials that can be used in electrodes for secondary battery applications include heating carbon-rich starting materials, such as minerals, such as petroleum coke and pitch coke; plant-based secondary materials, such as sucrose and glucose; man-made organic materials, such as polymeric hydrocarbons and other organic compounds, such as resorcinol formaldehyde; animal-derived materials, such as fertilizer; and plant-derived primary materials, such as coconut shells, coffee beans, straw, bamboo, rice husks, banana peels, etc., to temperatures above 500° C. in an oxygen-free atmosphere. When plant- and animal-derived materials are carbonized, "biochar" or biomass-charcoal is produced, which can be further processed to obtain hard carbon materials.

[0009] Soft carbon, on the other hand, is another form of carbon that is also structurally different from graphite, but is a graphitisale form of carbon that can change to include regions of graphitic structure at temperatures from about 750° C. to about 3200° C. Thus, soft carbon includes one or more graphitizable regions. However, even after this heat treatment, the change may not result in a completely graphitic structure, so that regions of non-graphitizable carbon material may still remain.

[0010] An important feature of commercially useful anode materials is the inclusion of a solid electrolyte interface (SEI) layer, which forms naturally as a result of the deposition of electrolyte decomposition products at the interface between the electrolyte and the anode surface during the first charge cycle of a pristine alkali metal-ion battery. It has been recognized for some time that this SEI layer is an essential component of alkali metal-ion batteries. This is because the SEI layer, first, protects the anode by impeding the transfer of electrons from the anode to the electrolyte, and second, allows alkali metal ions to transfer from the electrolyte to the anode, two factors that affect the battery cycle life. An ideal SEI layer would therefore be both an ion conductor and an electrical insulator. However, the formation of the SEI layer necessarily consumes some of the alkali metal ions that are desorbed from the cathode during the first charge cycle, meaning that they are unavailable for subsequent charge / discharge cycles. Since the residual amount of charge carriers in an individual rechargeable battery is constant, this reduction in available alkali metal ions results in an irreversible loss of capacity and therefore a loss of first cycle coulombic efficiency. [Prior art documents] [Patent documents]

[0011] [Patent Document 1] PCT / GB2020 / 050872 issue [Patent Document 2] US Patent Application Publication No. 2002 / 0192553A1 [Patent Document 3] U.S. Patent Publication No. 9899665B2 [Patent Document 4] US Patent Application Publication No. 2018 / 0287153A1 Summary of the Invention

[0012] The present work aims to control the formation of the SEI layer (and in particular its stability) in order to maximize its ionic conducting and electronic insulating properties and minimize the irreversible specific capacity, thereby maximizing the first cycle Coulombic efficiency.

[0013] Another important feature of a commercially useful anode material is the reversible specific capacity that can be achieved. Therefore, this work aims to maximize the anode reversible specific capacity of the anode material.

[0014] As described below, applicants engineered the surface and bulk chemistry, surface and bulk morphology, crystallinity, thickness, and pore structure of the anode electrode material to control the stability and robustness of the SEI layer, thereby minimizing the first cycle irreversible capacity loss. Additionally, applicants engineered the core structure of the anode material to maximize the anode reversible specific capacity of the anode material.

[0015] In particular, therefore, the present invention provides novel carbon-containing anode materials engineered to maximize first cycle coulombic efficiency and maximize anode reversible specific capacity. Additionally, the present invention provides novel processes for preparing such surface engineered carbon-containing anode materials. Such processes are cost-effective, especially on a commercial scale, and use readily available reactants.

[0016] The resulting surface engineered carbon-containing anode materials are useful in energy storage devices such as batteries, particularly secondary (rechargeable) batteries, alkali metal ion cells, especially sodium ion cells, electrochemical devices, and electrochromic devices. Importantly, these surface engineered carbon-containing anode materials provide energy storage devices with superior anode reversible specific capacity and first discharge capacity efficiency (Coulombic efficiency, calculated as the ratio of the total charge removed from the battery over the entire cycle to the total charge entering the battery), and significantly reduced irreversible capacity (first cycle loss). Additionally, the novel surface engineered carbon-containing anode materials of the present invention provide surprising and advantageous handling characteristics compared to prior art carbon-containing anode materials. [Brief description of the drawings]

[0017] The invention will now be described with reference to the following figures: [Figure 1] FIG. 1 shows a schematic diagram of a grain of pristine primary carbon-containing material and a grain of a surface engineered carbon-containing anode material according to the present invention. [Diagram 2] FIG. 2 shows a flow chart illustrating a preferred process of the present invention. [Diagram 3] FIG. 3 is a graph showing small angle X-ray scattering (SAXS) data for Example 1 in Table 3. [Figure 4] FIG. 4 is a graph showing small angle X-ray scattering (SAXS) data for Example 2 of Table 3. [Diagram 5] FIG. 5 is a graph showing small angle X-ray scattering (SAXS) data for Example 3 of Table 3. [Figure 6] FIG. 6 is a graph showing small angle X-ray scattering (SAXS) data for Example 4 in Table 3. [Figure 7] FIG. 7 is a graph showing small angle X-ray scattering (SAXS) data for Example 5 of Table 3. [Figure 8]FIG. 8 is a graph showing small angle X-ray scattering (SAXS) data for Control Example 1 in Table 3. [Figure 9] FIG. 9 is a graph showing small angle X-ray scattering (SAXS) data for Control Example 5 in Table 3. [Figure 10] FIG. 10 is a graph showing small angle X-ray scattering (SAXS) data for Control Example 8 in Table 3. [Figure 11] FIG. 11 is a graph showing small angle X-ray scattering (SAXS) data for Control Example 9 in Table 3. [Figure 12] FIG. 12 shows the X-ray diffraction (XRD) data for Example 1 of Table 1. [Figure 13] FIG. 13 shows the XRD data for Example 2 in Table 1. [Figure 14] FIG. 14 shows the XRD data for Example 3 in Table 1. [Figure 15] FIG. 15 shows the XRD data for Example 4 in Table 1. [Figure 16] FIG. 16 shows the XRD data for Example 5 in Table 1. [Figure 17] FIG. 17 shows the XRD data for Control Example 1 in Table 1. [Figure 18] FIG. 18 shows the XRD data for Control Example 4 in Table 1. [Figure 19] FIG. 19 shows the XRD data for Control Example 5 in Table 1. [Figure 20] FIG. 20 shows the XRD data for Control Example 8 in Table 1. [Figure 21] FIG. 21 shows the XRD data for Control Example 9 in Table 1. [Figure 22] FIG. 22 shows the XRD reference data for the MgO by-product deposit. [Figure 23] FIG. 23 shows an image of the pore-forming MgO material corresponding to the XRD of FIG. [Figure 24] FIG. 24 shows X-ray photoelectron spectroscopy (XPS) data for Example 1 of Table 3. [Diagram 25] FIG. 25 shows the XPS data for Example 2 in Table 3. [Figure 26] FIG. 26 shows the XPS data for Example 3 in Table 3. [Figure 27] FIG. 27 shows the XPS data for Example 4 in Table 3. [Figure 28] FIG. 28 shows the XPS data for Example 5 in Table 3. [Figure 29] FIG. 29 shows the XPS data for Control Example 1 in Table 3. [Diagram 30] FIG. 30 shows the XPS data for Control Example 4 in Table 3. [Diagram 31] FIG. 31 shows the XPS data for Control Example 8 in Table 3. [Diagram 32] FIG. 32 shows the BET N2 adsorption and corresponding specific surface area data for Example 2 of Table 3. [Diagram 33] FIG. 33 shows the BET N2 adsorption data and corresponding micropore specific surface area for Example 3 in Table 3. [Diagram 34] FIG. 34 shows the BET N2 adsorption and corresponding specific surface area data for Example 4 in Table 3. [Diagram 35] FIG. 35 shows the BET N2 adsorption and corresponding micropore specific surface area for Example 4 in Table 3. [Diagram 36] FIG. 36 shows the BET N2 adsorption and corresponding specific surface area data for Example 5 in Table 3. [Figure 37] FIG. 37 shows the BET N2 adsorption data and corresponding micropore specific surface area for Example 5 in Table 3. [Figure 38] FIG. 38 shows the BET N2 adsorption and corresponding specific surface area data for Example 6 in Table 3. [Figure 39] FIG. 39 shows the BET N2 adsorption data and corresponding micropore specific surface area for Example 6 in Table 3. [Diagram 40] FIG. 40 shows the BET N2 adsorption and corresponding specific surface area data for Control Example 1 in Table 3. [Diagram 41]FIG. 41 shows the BET N2 adsorption and corresponding micropore specific surface area for Control Example 1 in Table 3. [Diagram 42] FIG. 42 shows an image of an unplated anode electrode removed from a 9.5 mAh 3-electrode full cell after sodiation to about 410 mAh / g and subsequent desodiation to about 407 mAh / g in accordance with the present invention (Example 4, cell 005 with electrolyte 1 in Table 5). [Diagram 43] FIG. 43 shows the electrochemical data for a 3-electrode Na-ion full cell according to the characteristics of Example 3 (Cell 004) using Electrolyte 1 in Table 5. [Diagram 44] FIG. 44 shows the anode electrochemical data for a 3-electrode Na-ion full cell according to the characteristics of Example 4 (Cell 005) using electrolyte 1 in Table 5. [Diagram 45] FIG. 45 shows the electrochemical data for the cathode of a 3-electrode Na-ion full cell according to the characteristics of Example 4 (Cell 005) using electrolyte 1 in Table 5. [Diagram 46] FIG. 46 shows the anode electrochemical data for a 3-electrode Na-ion full cell according to the characteristics of Example 4 (Cell 007) using electrolyte 2 in Table 5. [Figure 47] FIG. 47 shows the cathode electrochemical data for a 3-electrode Na-ion full cell according to the characteristics of Example 4 (cell 007) using electrolyte 2 in Table 5. [Figure 48] FIG. 48 shows the anode electrochemical data for a 3-electrode Na-ion full cell according to the characteristics of Example 5 (Cell 008) using electrolyte 2 in Table 3. [Figure 49] FIG. 49 shows the cathode electrochemical data for a 3-electrode Na-ion full cell according to the characteristics of Example 5 (cell 008) using electrolyte 2 in Table 3. [Figure 50] FIG. 50 shows the anode electrochemical data for a 3-electrode Na-ion full cell according to the characteristics of Example 4 (Cell 009) using electrolyte 2 in Table 3. [Figure 51] FIG. 51 shows the cathode electrochemical data for a 3-electrode Na-ion full cell according to the characteristics of Example 4 (cell 009) using electrolyte 2 in Table 3. [Figure 52] FIG. 52 shows the anode electrochemical data for Control Example 2 (Cell 012) vs. Na metal half-cell using electrolyte 3 in Table 5. [Diagram 53] FIG. 53 shows the anode electrochemical data for Control Example 3 (Cell 013) vs. Na metal half-cell using electrolyte 1 in Table 5. [Figure 54] FIG. 54 shows the anode electrochemical data for Example 6 (Cell 010) vs. Na metal half-cell using electrolyte 1 in Table 5. [Figure 55] FIG. 55 shows the anode gravimetric capacity versus cycling for Example 2 (Cell 002) vs. Na metal half-cell using electrolyte 1 of Table 5. [Figure 56] FIG. 56 shows the anode gravimetric capacity versus cycling for Example 3 (cell 004) vs. Na metal half-cell using electrolyte 1 of Table 5. [Figure 57] FIG. 57 shows the anode specific capacity versus cycling for Na metal half-cells for Example 4 (cells 006 (open dots) and 007 (closed dots)) using electrolytes 1 and 2 from Table 5. [Figure 58] FIG. 58 shows the anode gravimetric capacity versus cycling for the Na metal half-cell for Example 5 (cell 008) using electrolyte 2 from Table 5. [Figure 59] FIG. 59 shows the anode specific capacity versus cycling for the Na metal half-cell for Example 4 (cell 009) using electrolyte 2 from Table 5. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0018] To achieve these goals, the present invention provides a carbon-containing anode material capable of inserting and desorbing alkali metal ions, comprising: a) i) a templated porous carbon material, and / or ii) a porous carbon material having a molecular weight of about 200 nm as determined using nitrogen gas BET analysis. 2 / g~about 1000m 2 a core comprising one or more primary carbon-containing materials selected from: b) an exterior surface comprising one or more carbonized materials chemically bonded onto one or more primary carbon-containing materials; having a carbon structure comprising 0 m determined using nitrogen gas BET analysis 2 / g~5m 2 The carbon-containing anode material has an open micropore specific surface area of ​​100 nm to 150 nm / g.

[0019] The activated carbon material of the present invention has a melting point of about 200 m as determined using nitrogen gas BET analysis. 2 / g~about 1000m 2 / g, which is not a requirement of the templated porous carbon material of the present invention.

[0020] As used herein, the term "core" refers to the central portion of the carbon structure. Additionally, as used herein, the phrase "chemically bonded" refers to the formation of chemical bonds, such as covalent bonds, between one or more primary carbon-containing materials and one or more carbonized materials. Thus, "strong bonds" are included within the meaning of this phrase, but "weak bonds," such as van der Waals interactions, are not included within the meaning of this phrase.

[0021] Because the carbonized material is "chemically bonded" to the primary carbon-containing material, preferably by using chemical vapor deposition in accordance with the present invention, this advantageously allows for engineering of the surface of the primary carbon-containing material at the individual particle level. Furthermore, because the secondary carbon-containing material of the present invention is pyrolyzed on one or more primary carbon-containing materials, this "bottom-up synthesis approach" allows carbon atoms to be attached to the outer surface of one or more primary carbon-containing materials. This advantageously provides precise control over the thickness and surface composition of the carbon-containing anode material of the present invention.

[0022] Thus, the carbon-containing anode material comprises one or more primary carbon-containing materials having an outer surface engineered to exhibit particular surface characteristics as described below, and most ideally, the carbon-containing anode material according to the present invention has a surface roughness of 0.1 nm as determined using nitrogen gas BET analysis. 2 / g~5m 2 1 or more primary carbon-containing materials having an outer surface engineered to exhibit an open micropore specific surface area of ​​0 m / g, as determined using nitrogen gas BET analysis. 2 / g~5m 2 An open micropore specific surface area of ​​greater than 1 / g can be used.

[0023] The selection of the core material of the carbon-containing anode material, ie, the core comprising one or more primary carbon-containing materials of the present invention, has surprisingly been found to have an impact on the anode reversible specific capacity of the anode material.

[0024] After being surface treated according to the present invention, a core comprising one or more primary carbon-containing materials selected from i) a templated porous carbon material and / or ii) an activated carbon material, wherein the activated carbon has a molecular weight of about 200 mm as determined using nitrogen gas BET analysis. 2 / g~about 1000m 2 It has been surprisingly found that said cores having a specific surface area of ​​1000 nm / g result in carbon-containing anode materials with improved anode reversible specific capacity.

[0025] The term "templated" as used herein refers to porous carbon materials produced by end-templating methods that use pore-forming substances (e.g., particles or organic and / or inorganic moieties) as templates.

[0026] Thus, "templated" porous carbon materials differ from those produced by physical activation (e.g., using reactive gases such as water vapor or CO2) and / or chemical activation (e.g., using hydroxides such as KOH or acids such as H3PO4) because these activation modes do not use pore-forming substances.

[0027] The pore-forming materials used in the end templating process are different from the activators used in the chemical activation process because they are engineered to be essentially inert to carbon (i.e., do not substantially oxidize carbon) and to locally block carbonization of the carbon source at and around the site where the pore-forming material is present. After removal of the pore-forming material, a pore structure is left that closely resembles the properties of the template, e.g., interconnectivity (or lack thereof), size and volume distribution. This is in contrast to the activators used in the chemical activation process, which are selected to oxidize carbon during or after the carbonization process.

[0028] Templated porous carbon materials have been found to be particularly preferred as the primary carbon-containing material of the present invention because the templating process provides greater control over the pore size and pore size distribution of the carbon material. This is in contrast to physical and / or chemical activation. More specifically, without wishing to be bound by theory, it is believed that templated porous carbon materials as the primary carbon-containing material of the present invention contain a more favorable average size and pore size distribution of the internal (closed) pores compared to the characteristics of the internal (closed) pores of non-templated hard carbon materials that have been heat treated to temperatures above 1600°C (typically 1800-3000°C). Indeed, annealing methods such as those used in the latter are known to enlarge the internal (closed) pores, but a side effect of such annealing treatments is that the storage capacity of the hard carbon is typically reduced.

[0029] Thus, the templated porous carbon material as the primary carbon-containing material of the present invention is then surface-treated according to the present invention to yield a carbon-containing anode material with surprisingly high anode reversible specific capacity, which is an unexpected advantage exhibited by the present invention.

[0030] In one embodiment, the carbon-containing anode material has a thermal conductivity of 0.1 ppm as determined using nitrogen gas BET analysis. 2 / g~5m 2 The carbon-containing anode material has a specific surface area of ​​about 1.5 m / g as determined using nitrogen gas BET analysis. 2 / g ~ approx. 3.5m 2 / g.

[0031] In one embodiment, the carbon-containing anode material comprises an average pore radius of about 9 Å or greater as determined using small angle x-ray scattering. Preferably, the carbon-containing anode material contains an average pore radius of from about 9 Å to about 30 Å, ideally from about 10 Å to about 15 Å, as determined using small angle x-ray scattering.

[0032] In one embodiment, the carbon-containing anode material has a viscosity of 0.1 m as determined using nitrogen gas BET analysis. 2 / g or less ~ 0m 2 / g of open micropore specific surface area. In one embodiment, the carbon-containing anode material comprises up to 5.0 atomic percent oxygen on its exterior surface, hi one embodiment, the carbon-containing anode material comprises a minimum of 92.0 atomic percent carbon on its exterior surface.

[0033] Suitable primary carbon-containing materials of the present invention are in any particulate (e.g., granular or powder) form and are capable of sodium ion insertion and desorption. Ideally, the primary carbon-containing materials are derived from the pyrolysis of plant-based materials, animal-derived materials, hydrocarbon materials, carbohydrate materials, and other carbon-containing organic materials. The primary carbon-containing materials can also include one or more carbon composite materials represented by (carbon)-X, where X is one or more elements selected from the group consisting of antimony, tin, phosphorus, sulfur, boron, aluminum, gallium, indium, germanium, lead, arsenic, bismuth, titanium, molybdenum, selenium, tellurium, silicon, carbon, and magnesium; or X is one or more oxides of elements selected from the group consisting of antimony, tin, phosphorus, sulfur, boron, aluminum, gallium, indium, germanium, lead, arsenic, bismuth, titanium, molybdenum, selenium, tellurium, silicon, carbon, and magnesium.

[0034] The templated porous carbon material, in one embodiment, can include graphitizable regions. An example of this is soft carbon. Thus, the templated porous carbon material can include or consist of templated soft carbon.

[0035] The templated porous carbon material may, in other embodiments, comprise non-graphitizable and non-graphitizable regions. An example of this is hard carbon. Thus, the templated porous carbon material may comprise or consist of templated hard carbon.

[0036] The templated porous carbon material can, in other embodiments, comprise or consist of templated graphite. In one embodiment, the templated porous carbon is selected from the group consisting of templated hard carbon, templated soft carbon, and templated graphite.

[0037] In one embodiment, the templated porous carbon material is derived from a carbon-containing starting material and then treated by an end templating process. Thus, in a preferred embodiment (or in other respects), the templated porous carbon material, preferably templated hard carbon, is (i) providing one or more carbon-containing starting materials together with one or more pore-forming materials and / or one or more compounds used to derive one or more pore-forming materials; (ii) optionally, first heating the components provided in step (i), preferably at a temperature of from about 60 to 950°C; (iii) optionally purifying the product obtained in step (ii); and (iv) pyrolyzing the components provided in step (i) or the optional products obtained in step (ii) or step (iii), preferably at a temperature of from about 600 to about 3000° C.; It can be formed by:

[0038] After formation, the templated porous carbon material obtained in step (iv) is subsequently subjected to a process for preparing a carbon-containing anode material, as defined by the present invention and described in more detail below.

[0039] Conveniently, the templated porous carbon material can be produced by heating one or more carbon-containing starting materials together with one or more pore-forming substances and / or one or more compounds used to induce the one or more pore-forming substances during heating to give rise to the templated porous carbon material. The heating is preferably carried out at a temperature of about 600 to about 3000°C, more preferably at a temperature of about 1000 to 1750°C, ideally at 1450±50°C. The heating is therefore preferably a pyrolysis treatment as defined in step (iv) above. Pyrolysis times of 5 minutes to 120 minutes are preferred, pyrolysis times of 30 minutes to 90 minutes are particularly preferred, and pyrolysis times of 60 minutes are ideal.

[0040] The advantage of using one or more compounds to induce one or more pore-forming substances during heating (e.g., using magnesium D-gluconate hydrate as a precursor to yield the pore-forming substance (MgO)) is that the primary carbon-containing material is generated in one step upon heating, i.e., one or more pyrogens are formed in-situ upon heating. It is also believed that the approach of using a precursor to yield the pore-forming substance upon heating results in a more uniformly dispersed pore-forming substance with a size distribution favorable for metal ion storage. The latter approach (e.g., using pre-synthesized MgO) has the advantage of being more cost-effective, but is generally less preferred due to the possibility of agglomeration and non-uniform distribution of the pore-forming substance within the bulk of the core carbon.

[0041] The one or more carbon-containing starting materials and one or more pore-forming substances and / or one or more compounds used to derive the one or more pore-forming substances during heating provided in step (i) are either i) a single carbon-containing compound containing one or more pore-forming substances and / or one or more compounds used to derive the one or more pore-forming substances during heating, or ii) a physical mixture comprising a combination of one or more carbon-containing starting materials and one or more pore-forming substances and / or one or more compounds used to derive the one or more pore-forming substances during heating, or iii) a mixture of i) and ii), preferably ii).

[0042] The pore-forming materials and / or compounds used to induce one or more pore-forming materials during heating can include salts (preferably magnesium or aluminum salts), inorganic compounds, and organometallic compounds (preferably metallocene compounds). Specific examples include magnesium oxide [MgO], magnesium acetate tetrahydrate [CH 14 MgO8], magnesium carbonate [MgCO3], magnesium D-gluconate hydrate [(Mg(CH 11O7)2·xH2O], silicon oxide [SiO2], aluminum oxide [Al2O3], aluminum acetate [Al(OH)(C2H3O2)2], aluminum carbonate [Al2(CO3)3], aluminum gluconate [C 18 H 33 AlO 21 ], iron gluconate [Fe[HOCH2(CHOH)4CO2]2], zirconium dioxide [ZrO2], titanium oxide [TiO2], metallocene compounds such as ferrocene [Fe(C5H5)2], or mixtures of such compounds. D-magnesium gluconate hydrate [(Mg(C6H 11 Magnesium salts such as HCl, HCl xH2O are particularly preferred.

[0043] Examples of pore-forming substances include salts (preferably magnesium salts) and inorganic compounds. Specific examples include magnesium oxide [MgO], silicon oxide [SiO2], aluminum oxide [Al2O3], zirconium dioxide [ZrO2], and titanium dioxide [TiO2].

[0044] Examples of compounds that may be used to induce one or more pore-forming materials during heating include salts (preferably magnesium or aluminum salts), inorganic compounds, and organometallic compounds (preferably metallocene compounds). A specific example is magnesium acetate tetrahydrate [CH 14 MgO8], magnesium carbonate [MgCO3], magnesium D-gluconate hydrate [(Mg(CH 11 O7)2·xH2O], aluminum acetate [Al(OH)(C2H3O2)2], aluminum carbonate [Al2(CO3)3], aluminum gluconate [C 18 H 33 AlO 21 ], iron gluconate [Fe[HOCH2(CHOH)4CO2]2], and metallocene compounds such as ferrocene [Fe(C5H5)2].

[0045] The single carbon-containing compound containing one or more pore-forming substances and / or one or more compounds used to induce one or more pore-forming substances during heating can include salts, preferably magnesium or aluminum salts. A specific example is magnesium acetate tetrahydrate [CH 14 MgO8], aluminum acetate [Al(OH)(C2H3O2)2], magnesium D-gluconate hydrate [(Mg(C6H 11 O7)2·xH2O], or aluminum gluconate [C 18 H 33 AlO 21 ] can be mentioned.

[0046] When a physical mixture is used in step (i) above, the one or more carbon-containing starting materials can include plant-based materials, biomass, animal-derived materials (including "animal-derived waste materials" obtained after food has passed through an animal's digestive tract and been excreted), hydrocarbon materials (including fossil fuel materials such as milled carbon fiber, coke, coal, coal pitch, coal tar, petroleum pitch, petroleum tar, resins and oils), carbohydrate materials (e.g., glucose, sucrose, or lignin), organometallic compounds (e.g., metallocenes), and other carbon-containing organic materials. Carbohydrates such as glucose are particularly preferred.

[0047] When a physical mixture is used as described above, in step (i), it is preferred that the one or more carbon-containing starting materials are selected from a hydrocarbon material and a carbohydrate material and that the one or more pore-forming substances and / or the one or more compounds used to derive the one or more pore-forming substances are selected from a salt, an inorganic compound, and an organometallic compound. In particular, it is preferred that in step (i), the one or more carbon-containing starting materials comprise a carbohydrate material and the one or more pore-forming substances and / or the one or more compounds used to derive the one or more pore-forming substances comprise a magnesium salt.

[0048] Similarly, when a physical mixture is used, step (i) can further include a mixing step, which can include, but is not limited to, drying and solvent-mediated blending techniques. This involves mixing one or more carbon-containing starting materials together with one or more pore-forming substances and / or one or more compounds used to derive one or more pore-forming substances in a desired mass ratio (e.g., 1:1 molar ratio on an anhydrous mass basis) to control the degree of templating. Ideally, the mixing step provides a homogenous mixture to ensure a uniform concentration of one or more carbon-containing starting materials with one or more pore-forming substances throughout the formulation.

[0049] Solvent-mediated blending techniques can involve first dissolving, solvating, or dispersing, in an aqueous or non-aqueous solvent, one or more carbon-containing starting materials together with one or more pore-forming substances and / or one or more compounds used to derive the one or more pore-forming substances. The mixture of one or more carbon-containing starting materials, preferably homogeneously dissolved, solvated, or dispersed with one or more pore-forming substances and / or one or more compounds used to derive the one or more pore-forming substances, is then preferably separated from the solvent by dehydration (e.g., evaporation and / or sublimation using drying and / or freeze-drying techniques), sedimentation (e.g., using gravity, filtration, phase separation, or centrifugal force), or recrystallization, or a combination of these methods.

[0050] When a physical mixture is used as described above, it may be beneficial to subject the physical mixture to an initial heating step prior to pyrolysis to eliminate any volatile compounds from the mixture (e.g., by evaporation, sublimation, or decomposition). This is optional step (ii). More specifically, the initial heating step may be carried out at a temperature of about 60-200° C. (e.g., drying) or at a temperature of about 80-250° C. The initial heating is preferably carried out under a non-oxidizing atmosphere which may include one or more selected from nitrogen, carbon dioxide, and argon, and may optionally include a reducing agent such as hydrogen (e.g., 1-5 wt % hydrogen in argon).

[0051] Alternatively, or additionally, when a physical mixture is used, it may be beneficial to subject the physical mixture to an initial heating step prior to pyrolysis to oxidize and / or carbonize (i.e., carbonize) the one or more carbon-containing starting materials. This is also considered optional step (ii). This treatment may be particularly advantageous when the one or more carbon-containing starting materials are hydrocarbon materials (including fossil fuel materials such as milled carbon fiber, coke, coal, coal pitch, coal tar, petroleum pitch, petroleum tar, resins and oils), carbohydrate materials (e.g., glucose, sucrose, or lignin), organometallic compounds (e.g., metallocenes), and other carbon-containing organic materials. More specifically, the initial heating step in these cases may be performed at a temperature of about 250-950° C. This initial heat treatment is particularly advantageous because it disperses the one or more pore-forming substances and / or the one or more compounds used to derive the one or more pore-forming substances within the one or more carbon-containing starting materials in the physical mixture.

[0052] When a physical mixture is used as described above and the one or more carbon-containing starting materials are hydrocarbon materials (including fossil fuel materials such as milled carbon fiber, coke, coal, coal pitch, coal tar, petroleum pitch, petroleum tar, resins and oils), a partial oxidation step can be employed before or during the initial heat treatment (carbonization) described above (i.e., before or during optional step (ii)). This partial oxidation step advantageously increases the oxygen content of the resulting material and inhibits graphitization during subsequent thermal processing steps. After subsequent thermal processing steps, the final result is a hard carbon material.

[0053] Alternatively, or additionally, if a physical mixture is used, it may be beneficial to solvothermally or hydrothermally carbonize the physical mixture prior to pyrolysis. Solvothermal or hydrothermal carbonization can be carried out in a single reaction vessel (e.g., a sealed autoclave with an inert or reactive lining) at a temperature of 50-600°C. In this case, the pressure is preferably maintained above 1 bar and a solvent may be used if necessary.

[0054] The initial heating in optional step (ii) is typically for about 5 minutes to about 180 minutes, preferably about 60 minutes to about 180 minutes, and ideally about 30 minutes to about 120 minutes. Temperatures of about 60 to 950°C are preferred, more preferably about 250 to 950°C, and ideally about 600°C.

[0055] During the production of the templated porous carbon material, the particles of the one or more carbon-containing starting materials, including the one or more pore-forming substances, desirably have a d50 particle size of about 1 μm to about 25 μm, more preferably about 8 μm to about 25 μm. A d50 particle size of about 4 μm to about 15 μm is also preferred. Thus, after the initial heat treatment, an optional primary milling step can be carried out before the subsequent steps described below. That is, an optional milling step can be carried out on the product obtained in step (ii) (i.e. between steps (ii) and (iii)).

[0056] After the initial heat treatment (e.g., carbonization) and optional milling, the resulting carbon material is preferably treated in an optional step (iii) to remove (or at least partially remove) unwanted materials from the carbon material. Thus, in optional step (iii), the product obtained in step (ii) is purified. Ideally, such purification involves desalting. Such unwanted materials may include one or more pore-forming substances used in the process for preparing the templated porous carbon material, or other unwanted inorganic impurities that were present in the one or more carbon-containing starting materials prior to carbonization. This treatment step preferably involves the use of any suitable treatment process or any suitable equipment known to those skilled in the art to separate and remove unwanted materials. For example, this may involve the use of dissolution, solvation, filtration, centrifugation and sedimentation techniques known to those skilled in the art. The use of ion exchange materials, chemical separation techniques, chromatographic separation techniques, electrophoretic separation techniques, the use of complexing agents, phase separation, or chemical precipitation techniques may also be desirable. Physical techniques, such as melting or evaporation, may also be used.

[0057] In a preferred embodiment, the carbonized material is chemically treated to dissolve, solvate or disperse any unwanted soluble or dispersible material that may be present as described above. This preferred chemical treatment step is ideally carried out in a solution having a pH value above and / or below 7, preferably above 8 and / or below 6, and consequently involves treating the carbonized material using alkaline and / or acidic solutions. Thus, step (ii) preferably involves the use of alkaline and / or acidic conditions.

[0058] The alkaline treatment is typically carried out in a concentrated solution of an alkaline reagent dissolved in a suitable solvent, preferably water. Preferably, the solution is an alkaline solution of at least 2.0 M, or a molten bath, preferably a pure molten bath. One or more alkaline reagents can be used, for example one or more selected from alkali metals, alkaline earth metals, ammonia, and water-soluble hydroxides. Potassium hydroxide and sodium hydroxide, or mixtures thereof, are suitable alkaline reagents, and molten baths containing alkali metal hydroxides, for example NaOH (10-90%) and / or KOH, are particularly ideal. The resulting alkaline-treated carbon material is then removed from the alkaline solution and washed or rinsed at least once (preferably multiple times) with at least one solvent that dissolves and facilitates the removal of unwanted material and residual alkaline reagent. The washing solvent preferably has a pH value of about 6-8, and deionized water is particularly ideal. Thereafter, if necessary, filtration or centrifugation of the alkaline-treated carbon material, together with drying of the material, may be followed as a final step.

[0059] The acid treatment is typically carried out in a solution of an acidic reagent dissolved in a suitable solvent, preferably water. Suitable acids include one or more selected from hydrochloric acid (>0.1M), hydrofluoric acid (10-50%), nitric acid and sulfuric acid (40-90%). The acidic solution is preferably dilute; solutions from 1.0M to less than 3.0M work well, with 2.0M solutions being particularly preferred, preferably 2.0M HCl solutions. A boiling solution of 2.0M HCl solution can also be used. The resulting acid-treated carbon material is then removed from the acidic solution and washed or rinsed at least once (preferably multiple times) with at least one solvent that dissolves and facilitates the removal of unwanted material and residual acidic reagent. The washing solvent preferably has a pH value of about 6-8, with deionized water being particularly ideal. If necessary, filtration or centrifugation of the acid-treated templated porous carbon material may then be followed as a final step, along with drying of the material.

[0060] The templated porous carbon material used in the present invention preferably has a d50 particle size of about 1 μm to about 25 μm, more preferably about 8 μm to about 25 μm. A d50 particle size of about 4 μm to about 15 μm is also preferred. Thus, an optional primary milling step (or an additional milling step, if a primary milling step may be necessary as described above) can be carried out. The optional milling step can be carried out after step (iii) and before step (iv). Alternatively, or additionally, milling can be carried out after step (iv). The pyrolysis in step (iv) is as defined above.

[0061] The one or more carbon-containing starting materials (i.e., sources from which the templated porous carbon material can be derived) used to generate the templated porous carbon material can include disordered and / or ordered carbon-containing materials. Particularly preferred carbon-containing starting materials include hard carbon, soft carbon, and graphite, with hard carbon being particularly preferred.

[0062] The one or more carbon-containing starting materials (i.e., sources from which the templated porous carbon material can be derived) used to generate the templated porous carbon material can include disordered carbon-containing materials, and are more preferably selected from the group consisting of conventional carbon anode materials (e.g., hard carbon anode materials); high temperature hard carbon that is not fully graphitized (e.g., when the hard carbon material is annealed at a temperature above 2000° C.); carbon-metal, carbon-metalloid, or carbon-nonmetal composite materials (e.g., carbon-Sb, carbon-Sn, carbon-Si, carbon-Pb, carbon-Ti, and carbon-P) (hard carbon analogs of these materials are particularly preferred); soft carbon materials; carbon-conductive additive mixtures (e.g., hard carbon-carbon black mixtures, a suitable carbon black being Super C65 available commercially from Imerys). TMmaterials); carbon-oxide composite materials (e.g., hard carbon-Fe2O3, hard carbon-Sb oxide, hard carbon-Sn oxide, hard carbon-Sb / Sn oxide); and carbon-carbide composite materials (e.g., hard carbon-SiC composite materials); and activated carbon materials (e.g., materials with a BET surface area of ​​>100 m 2 The carbon black may include one or more materials selected from the group consisting of activated hard carbon (e.g., activated hard carbon having a carbon content of 100 / g).

[0063] Other preferred carbon-containing starting materials include a combination of carbon (e.g., hard carbon, soft carbon as described above) and one or more elements and / or compounds. Particularly preferred combinations include carbon / X materials, where X can be one or more elements such as antimony, tin, phosphorus, sulfur, boron, aluminum, gallium, indium, germanium, lead, arsenic, bismuth, titanium, molybdenum, selenium, tellurium, silicon, carbon, or magnesium. Carbon / Sb, carbon / Sn, carbon / Sb x Sn y , carbon / phosphorus, carbon / silicon, carbon / silicon carbide (HC / SiC), or carbon / sodium silicate are suitable carbon-containing materials. Particularly preferred are one or more hard carbon analogues of these materials. Further preferred combinations include carbon / X materials, where X can be one or more oxides of elements selected from the group consisting of antimony, tin, phosphorus, sulfur, boron, aluminum, gallium, indium, germanium, lead, arsenic, bismuth, titanium, molybdenum, selenium, tellurium, silicon, carbon, and magnesium.

[0064] In some embodiments, the one or more carbon-containing starting materials can contain one or more metal and / or nonmetal ions that can act as dopants in the final carbon-containing anode material. These metal and / or nonmetal ions can be added to the one or more primary carbon-containing materials before surface treatment with a carbonizing material as described below, or can be added to the one or more carbon-containing starting materials used to make the templated porous carbon material before pyrolysis. Alternatively, the one or more metal and / or nonmetal ions can be selectively retained in the one or more carbon-containing starting materials before pyrolysis, and thus become carried into the templated porous carbon material.

[0065] Conveniently, one or more carbon-containing starting materials including hard carbon and / or soft carbon used to generate the templated porous carbon material can be generated by pyrolysis (high temperature processing, typically greater than 700° C. to 2500° C.) of carbon-based materials, such as plant-based materials, biomass, animal-derived materials (including "animal-derived waste materials" obtained after food has passed through an animal's digestive tract and been excreted), hydrocarbon materials (including fossil fuel materials such as milled carbon fiber, coke, coal, coal pitch, coal tar, petroleum pitch, petroleum tar, resins and oils), carbohydrate materials (e.g., glucose, sucrose, or lignin), organometallic compounds (e.g., metallocenes), and other carbon-containing organic materials, typically under a non-oxidizing atmosphere including one or more selected from nitrogen, carbon dioxide, other non-oxidizing gases, and inert gases such as argon.

[0066] Preferably, the carbon-based material used to produce one or more carbon-containing starting materials is subjected to a number of processes, including carbonization (typically at temperatures between 150° C. and ≦700° C.), decomposition, chemical treatment (e.g., using acidic and / or alkaline conditions), filtration, centrifugation, “heavy liquid separation” or “sink-float separation”, use of ion exchange materials, chromatographic separation techniques, electrophoretic separation techniques, use of complexing agents or chemical precipitation techniques, and milling (typically to a d of about 8 to 25 μm) to remove unwanted non-carbon-containing materials (e.g., metal-containing ions (such as transition metals, alkali metals, or alkaline earth metals), and non-metal-containing ions (e.g., phosphorus, oxygen, hydrogen)), ideally prior to pyrolysis. 50 The pulp is refined using process steps that may include one or more selected from the following: milling to a particle size of 15-25 μm, filtering through a 15-25 μm sieve to remove larger particles.

[0067] As described above, after being surface treated according to the present invention, a core comprising one or more primary carbon-containing materials selected from i) a templated porous carbon material and / or ii) an activated carbon material, wherein the activated carbon has a molecular weight of about 200 mm or less as determined using nitrogen gas BET analysis. 2 / g~about 1000m 2 It has been surprisingly found that said cores having a specific surface area of ​​1000 nm / g result in carbon-containing anode materials with improved anode reversible specific capacity.

[0068] A preferred activated carbon material according to the present invention has a melting point of about 250 m 2 / g~about 1000m 2 / g, preferably about 300m 2 / g~about 800m 2 / g, very preferably about 500m 2 / g~about 800m 2 / g.

[0069] In one embodiment, the particle size distribution of the one or more primary carbon-containing materials is from about 1 nm to about 30 μm, preferably from about 1 nm to 20 μm. In particular, applicants understand that the surface treatment of the present invention does not substantially change the particle size distribution of the one or more primary carbon-containing materials. Thus, this range applies to the particle size distribution of the one or more primary carbon-containing materials before the carbonized material is chemically bonded to the one or more primary carbon-containing materials and after the treatment has been performed.

[0070] In one embodiment, the one or more primary carbon-containing materials have a d of about 0.01 μm to about 4 μm. 10 It has a particle size. In one embodiment, the one or more primary carbon-containing materials have a d 50 In another embodiment, the one or more primary carbon-containing materials have a particle size of about 1 to about 25 μm, preferably about 8 to about 25 μm. 50 It has a particle size.

[0071] In one embodiment, the one or more primary carbon-containing materials have a d 90 It has a particle size. The surface properties of the carbon-containing anode material according to the present invention were investigated using the BET technique to determine the specific surface area of ​​the open micropores, i.e., micropores that have openings on the surface of the carbon-containing anode material. In this specification, the "surface" literally means the outside of the carbon-containing anode particle. Pores designated as "micropores" are pores with a diameter of less than 2 nm, which are different from "mesopores", which are pores with a diameter of about 2 nm to 50 nm.

[0072] Applicants have demonstrated that surface engineered carbon-containing anode materials according to the present invention have a thermal conductivity of 0.1 ppm or less as determined using nitrogen gas BET analysis. 2 / g and up to 5m 2 / g, preferably up to 0.9m 2 / g, particularly preferably up to 0.5m 2 / g, very preferably up to 0.3m 2 / g, most preferably up to 0.15m 2 It has been found that significantly improved electrochemical performance can be achieved in electrochemical cells using open micropore specific surface areas of up to 100 nm / g.

[0073] The surface engineered carbon-containing anode materials according to the present invention are advantageously produced when one or more primary carbon-containing materials (in solid form, preferably in particulate, granular or powder form) are treated together with one or more secondary carbon-containing materials. By this treatment, the carbonized material is preferably chemically bonded, more preferably chemically attached, to the primary carbon-containing materials. In a highly preferred embodiment, the use of chemical vapor deposition is employed in the process of the present invention.

[0074] However, the present invention is not limited to the use of chemical vapor deposition, and indeed, those skilled in the art will be aware of alternative methods for chemically bonding materials to the primary substrate, examples of which may include plasma-enhanced deposition, atomic layer deposition, and physical vapor deposition.

[0075] As referred to herein, a "carbonized material" is a carbon-rich solid species derived from one or more secondary carbon-containing materials. Most particularly, the present invention employs such carbonized materials as an extremely thin deposit on the outer surface of one or more primary carbon-containing materials. The carbonized material is preferably deposited substantially uniformly over the entire surface of the inner core, but it is important to note that the deposit does not necessarily have to be in the form of a complete layer or even coating (i.e., the primary carbon-containing material and the deposited carbonized material do not necessarily have to be in a core / full shell type arrangement). Nevertheless, the material, when deposited, preferably has a thickness of less than 1 nm to 500 nm, more preferably less than 10 nm to 500 nm, and very preferably 10 nm to 250 nm. Ideally, 10% to 90% of the surface area of ​​the outer surface of the one or more primary carbon-containing materials is covered with the carbonized material derived from one or more secondary carbon-containing materials. The mass of the deposit is also extremely small (typically 2.2±0.8% by weight per 30 minutes of deposition time). Thus, the carbonized material does not substantially alter the particle size distribution of the one or more primary carbon-containing materials, as described above.

[0076] Preferably, suitable secondary carbon-containing materials from which the carbonized material is derived may be selected from one or more organic and / or hydrocarbon materials, such as alkanes, alkenes, alkynes or arenes, which may be linear, branched, cyclic, aliphatic or aromatic. The secondary carbon-containing material itself may be derived from coal or petroleum-based tar or pitch, resins, oils, or plant-based materials. n H 2n+2 Especially preferred is a secondary carbon-containing material comprising one or more gaseous hydrocarbons having the formula:

[0077] In one embodiment, the secondary carbon-containing material from which the carbonized material is derived can include a vapor phase, a liquid phase, and / or a gas phase at at least one temperature of about 950° C. or less. Preferably, the secondary carbon-containing material can include a vapor phase, a liquid phase, and / or a gas phase at at least one temperature of about 200° C. or more and about 950° C. or less.

[0078] It has been found that the specific surface area of ​​the open micropores of the carbon-containing anode material of the present invention is dramatically smaller than the specific surface area of ​​the open micropores of the primary carbon-containing material before treatment with the carbonized material derived from one or more secondary carbon-containing materials (as described above). This is believed to be because at least some of the openings of the open micropores of the carbon-containing anode material (i.e., those at the surface) are "blocked" or "clogged" by the attached carbonized material. Preferably, the presence of the chemically attached carbonized material derived from one or more secondary carbon-containing materials reduces the surface micropore area of ​​the carbon-containing anode material compared to the surface area of ​​the open micropores of the primary carbon-containing material before or after treatment with the carbonized material. The significant reduction in the surface area of ​​the open micropores seems to support the applicant's current understanding that the attached carbonized material blocks only the surface (open) micropores, and this notion is further supported by the fact that no significant weight gain has been measured for the primary carbon-containing material after treatment with the carbonized material.

[0079] As noted above, the present invention provides a carbon-containing anode material that includes a carbonized material adhered or partially adhered to an outer surface of a primary carbon-containing material. The carbonized material may be a "soft" carbon-containing species that is graphitized to some degree by thermal processes, and the presence of graphitized material can be confirmed, for example, by Raman spectroscopy, X-ray diffraction, or high-resolution transmission electron microscopy. However, it is important to control the formation of the carbon-containing anode material to have a degree of graphitization appropriate for the particular cell chemistry in which it is used. For example, it is highly preferred to limit graphitization in the case of Na-ion cells to levels often observed in conventional hard carbon materials. That is, since graphite is much less electrochemically active toward sodium than hard carbon, it is desirable to avoid highly graphitized soft carbon-containing species on the surface of the primary carbon-containing material for the purpose of reversible sodiation. However, the opposite is true for lithium-ion cells.

[0080] Care must be taken to avoid the formation of highly graphitized regions, since they catalyze various parasitic reactions (e.g., when propylene carbonate (PC) is used in the electrolyte composition). Thus, it has been found that extreme annealing does not improve the carbon anode efficiency. On the other hand, surface treatment according to the invention has been found to consistently improve the efficiency of carbon-containing anode materials, regardless of the electrolyte system. However, the method of the invention does not affect the volume of closed pores. This is evident from the fact that primary carbon-containing materials before and after treatment with carbonized materials produce similar (de)sodium potential profiles.

[0081] Another preferred property of the surface of the carbon-containing anode material according to the present invention is a very low degree of surface oxygen content. It is known that the presence of compounds with oxygen-containing groups (e.g., CO, C=O and C(=O)OH functional groups) on the surface of the carbon-containing material tends to act as permanent anchor points for incoming charge carriers and as platforms for undesired parasitic reactions, both of which contribute to first cycle losses when these carbon-containing materials are used as anode materials. Advantageously, the carbon-containing anode material according to the present invention has a surface oxygen content of 0 atomic percent (atm.%) to about 5.0 atm.%, preferably 0 atomic percent (atm.%) to about 2.5 atm.%, as measured using X-ray photoelectron spectroscopy (XPS). Thus, in accordance with the present invention, treating one or more primary carbon-containing materials with a carbonized material derived from one or more secondary carbon-containing materials has the effect of reducing the surface oxygen content of the primary carbon-containing materials by at least 30 atomic %, preferably at least 50 atomic %, and more preferably at least 90 atomic %. In some embodiments, a reduction of nearly 100 atomic % of the surface oxygen atoms is possible.

[0082] The specific surface area of ​​the entire carbon-containing anode material is also generally considered as another useful factor that affects the degree of irreversible capacity and first cycle loss. However, in the present invention, the treatment of one or more primary carbon-containing materials with a carbonized material derived from one or more secondary carbon-containing materials actually reduces the specific surface area of ​​the carbon-containing anode, but this reduction is not as significant as the reduction in the micropore surface area. All specific surface area values ​​described in this application are determined using BET N2 analysis. Figure 1 is discussed in detail below to theoretically explain the mechanism by which the surface of the carbon-containing anode material according to the present invention can cause the observed significant reduction in open (surface) micropore surface area while recording a minimal reduction in the overall surface area.

[0083] In accordance with the present invention, one or more primary carbon-containing materials are treated with one or more secondary carbon-containing materials to achieve the desired surface engineered carbon-containing anode material by contacting the one or more primary carbon-containing materials with a carbonized material derived from the one or more secondary carbon-containing materials.

[0084] Contacting the primary carbon-containing material with the one or more secondary carbon-containing materials can be accomplished using any suitable method, such as by directly contacting the primary carbon-containing material with the one or more secondary carbon-containing materials or by contacting the primary carbon-containing material with the one or more secondary carbon-containing materials and then promoting the formation of a carbonized material from the one or more secondary carbon-containing materials.

[0085] Suitably, contacting the primary carbon-containing material with one or more secondary carbon-containing materials can include a solvent-mediated procedure in which the solid primary carbon-based material is mixed with one or more solvents and / or other liquids in which the secondary carbon-containing materials are dissolved, solvated or dispersed, followed by removal of the solvent / dispersant before carbonizing the secondary carbon-containing material. Alternatively, a mechanochemical procedure can be used in which one or more primary and secondary carbon-containing materials are mixed together (without a solvent or other dispersant, or with a mixing aid) before carbonizing the secondary carbon-containing material. Or, in yet another method, a diffusion-based system can be used in which one or more primary carbon-containing materials in solid form are contacted with one or more secondary carbon-containing materials in vapor and / or gaseous form, followed by heating to carbonize the secondary carbon-containing materials.

[0086] In another aspect, the present invention provides a process for preparing a carbon-containing anode material capable of inserting and deintercalating alkali metal ions, comprising the steps of: a) i) a templated porous carbon material, and / or ii) a porous carbon material having a molecular weight of about 200 nm as determined using nitrogen gas BET analysis. 2 / g~about 1000m 2 an activated carbon material having a specific surface area of ​​1 / g; and b) contacting the core with one or more secondary carbon-containing materials at a temperature of up to 950° C., thereby forming a carbon-containing anode material having an outer surface comprising one or more carbonized materials chemically bonded onto the one or more primary carbon-containing materials, the outer surface being at least 0.1 μm as determined using nitrogen gas BET analysis; 2 / g~5m 2 providing said carbon-containing anode material having an open micropore specific surface area of ​​100 / g; The preparation process further comprises:

[0087] The one or more solid primary carbon-containing materials are preferably in any particulate form (e.g., granules or powder), as described above. In one embodiment, the particle size distribution of the one or more primary carbon-containing materials is from about 1 nm to about 30 μm, as described above.

[0088] Suitable primary carbon-containing materials for use in the process of the present invention are those described above in connection with the carbon-containing anode material according to the present invention. In particular, preferably the templated porous carbon material, more preferably the templated hard carbon, is (i) providing one or more carbon-containing starting materials together with one or more pore-forming materials and / or one or more compounds used to derive one or more pore-forming materials; (ii) optionally, first heating the components provided in step (i), preferably at a temperature of from about 60 to 950°C; (iii) optionally purifying the product obtained in step (ii); and (iv) pyrolyzing the components provided in step (i) or the optional products obtained in step (ii) or step (iii), preferably at a temperature of from about 600 to about 3000° C.; It can be formed by:

[0089] The preferred processes above can be further defined as above or according to the examples disclosed herein. The activated carbon material of the present invention has a melting point of about 200 m as determined using nitrogen gas BET analysis. 2 / g~about 1000m 2 / g. This is not a requirement of the templated porous carbon materials of the present invention. A preferred activated carbon material according to the present invention has a specific surface area of ​​about 250 m 2 / g~about 1000m 2 / g, preferably about 300m 2 / g~about 800m 2 / g, very preferably about 500m 2 / g~about 800m 2 / g.

[0090] With respect to step b) in the preparation of a carbon-containing anode material, the heating conditions are selected to i) promote deposition of the one or more secondary carbon-containing materials onto the surface of the primary carbon-containing material (where the one or more secondary carbon-containing materials are materials that are carbonized prior to contacting the primary carbon-containing material), or ii) promote carbonization of the one or more secondary carbon-containing materials already present on the surface of the primary carbon-containing material, or iii) promote carbonization of the one or more secondary carbon-containing materials and subsequent deposition of the resulting carbonized materials on the surface of the primary carbon-containing material.

[0091] In each case, the end result is that a chemical bond, such as a covalent bond, is formed between the one or more primary carbon-containing materials and the one or more carbonized materials, such that the one or more carbonized materials are chemically bonded to, and preferably chemically attached to, the surface of the one or more primary carbon-containing materials.

[0092] The temperature used is preferably below that which would cause substantial graphitization of the carbonized material, particularly if the resulting carbon-containing anode material is for use in a sodium-ion cell (as described above). However, it is important that the temperature used in accordance with the process of the present invention chemically bonds the carbonized material to the primary carbon-containing material.

[0093] As noted above, the secondary carbon-containing material, which is preferably the source of the carbonized material, can therefore include a vapor and / or liquid and / or gas phase at at least one temperature of about 950° C. or less. A vapor and / or liquid and / or gas phase at at least one temperature of about 200° C. or more and about 950° C. or less is preferred.

[0094] Preferably, the maximum temperature is 930°C, more preferably, the maximum temperature is 900°C, and especially preferably, the maximum temperature is 880°C. The minimum heating temperature is any temperature that allows carbonization of the secondary carbon-containing material to occur and depends on the secondary carbon-containing material used. A minimum temperature of 600°C is usually sufficient, but lower temperatures are possible if a catalyst or other reagent is used to reduce the activation energy required for thermocatalytic decomposition and carbonization of the secondary carbon-containing material. Possible catalysts include small amounts of one or more metal compounds or metal oxide compounds, such as transition metals or transition metal oxides.

[0095] As noted above, suitable secondary carbon-containing materials from which the carbonized material is derived can be selected from one or more organic and / or hydrocarbon materials, such as alkanes, alkenes, alkynes or arenes, which can be linear, branched, cyclic, aliphatic or aromatic. The secondary carbon-containing material itself can be derived from coal or petroleum-based tar or pitch, resins, oils, or plant-based materials. n H 2n+2 Especially preferred is a secondary carbon-containing material comprising one or more gaseous hydrocarbons having the formula:

[0096] In a preferred process of the present invention, the total pressure, total flow rate, and individual partial pressures and individual flow rates of the reagents when contacting the primary carbon-containing material with either a fluid (liquid, vapor, aerosol, or gaseous) secondary carbon-containing material or a fluid (liquid, vapor, aerosol, or gaseous) carbonized material preformed as a secondary carbon-containing material are optimized to ensure deposition of an appropriate amount of carbonized material on the primary carbon-containing material. The preferred total pressure, total flow rate, and individual partial pressures and individual flow rates of the secondary carbon-containing material are within 10 -6 ~3×10 7 Pa, 0.001~1000L / min, 10 -6 ~3×10 7 Pa, and in the range of 0.001 to 1000 L / min, and more preferably 10 4 ~10 6 Pa, 0.01~100L / min, 104 ~10 6 Pa, and 0.01 to 100 L / min, and highly preferably 5×10 4 ~5×10 5 Pa, 0.1~10L / min, 5×10 4 ~5×10 5 Pa, and in the range of 0.1 to 10 L / min.

[0097] Injection chemical vapor deposition (CVD) systems and aerosol-assisted reactors are examples of configurations in which the pressure and flow rate of individual fluid precursors can be controlled. In a further preferred process of the present invention, the concentration of the carbonized material and / or the concentration of the one or more secondary carbon-containing materials used for contacting with the one or more primary carbon-containing materials is preferably in the range of 0.001 to 100 vol. %, preferably 0.01 to 10 vol. %, more preferably 0.01 to 5 vol. %, very preferably 0.05 to 0.1 vol. % in the carrier gas for gaseous secondary carbon-containing materials and preferably in the range of 0.001 to 100 vol. % in the solvent or carrier liquid for liquid and semi-solid (e.g. pitch, tar, oil) secondary carbon-containing materials.

[0098] In a further preferred process of the present invention, the duration of the heating step (annealing time) is also preferably adjusted i) to minimize and preferably prevent substantial graphitization of the carbonized material - the longer the heating time, the greater the likelihood that the carbonized material will become substantially graphitized - and ii) to ensure that the time is sufficient to chemically deposit enough carbonized material to fill at least a portion of the surface micropores, as described above.

[0099] As noted above, the process of the present invention is not limited to the use of chemical vapor deposition. Indeed, those skilled in the art will know alternative methods for chemically bonding materials to the primary substrate, which are encompassed within the scope of the present invention. Examples of these include plasma-enhanced deposition, atomic layer deposition, and physical vapor deposition.

[0100] The annealing time is preferably between 5 minutes and 120 minutes, with annealing times between 30 minutes and 90 minutes being particularly preferred. The annealing time is the period of time required for the one or more secondary carbon-containing materials to adhere onto the one or more primary carbon-containing materials.

[0101] In a particularly preferred process of the present invention, the step of contacting one or more primary carbon-containing materials in solid form with one or more secondary carbon-containing materials is carried out using any means necessary to ensure that at least a portion of the surface of each particle of the primary carbon-containing materials is in contact with the one or more secondary carbon-containing materials. Suitable means include stirring or agitating the primary carbon-containing materials when contacting them with the one or more secondary carbon-containing materials; spraying, atomizing, aerosolizing or fluidizing particles of the primary carbon-containing materials into an atmosphere containing the one or more vaporized, sprayed, atomized, emulsified or aerosolized secondary carbon-containing materials; and spreading the primary carbon-containing materials on a flat plate or wide-mouthed reaction vessel before introducing the one or more secondary carbon-containing materials.

[0102] Furthermore, in a particularly preferred process of the present invention, the step of contacting the one or more primary carbon-containing materials in solid form with the one or more secondary carbon-containing materials is preferably performed as the final step of the process of the present invention. More particularly, this step is highly preferably performed after any abrasive treatment (e.g., milling, grinding, crushing, etc.) of the one or more primary carbon-containing materials. This advantageously avoids disturbing the outer surface comprising the one or more carbonized materials chemically bonded to the one or more primary carbon-containing materials. For example, after surface treatment including abrasive treatment, the passivated surface may crack open exposing micropores or the carbon purity may decrease due to, for example, partial oxidation or hydration of the surface.

[0103] For the avoidance of doubt, post surface treatment steps such as mixing of active material and binder, electrode printing (e.g., coating) and electrode calendaring (e.g., rolling) are not considered to be "polishing treatments" within the meaning of this phrase.

[0104] The carbon-containing anode material according to the present invention is suitable for use as an electrode active material in secondary battery applications, particularly in alkali metal ion cells, especially sodium ion cells. In another aspect, the present invention provides an alkali metal ion cell comprising at least one negative electrode (anode) as described above, which has a 0.1% or less charge-discharge current (Pt) as determined using nitrogen gas BET analysis. 2 / g super~5m 2 It is preferred that the specific open micropore surface area is 0 m / g, as determined using nitrogen gas BET analysis. 2 / g super~5m 2 / g of open micropore specific surface area can be used.

[0105] The alkali metal ion cell also includes a positive electrode (cathode) which preferably includes one or more active positive electrode materials capable of inserting and extracting alkali metals, the active positive electrode materials being preferably selected from oxide-based materials, polyanion materials, and Prussian blue analogue-based materials. Particularly preferably, the one or more active positive electrode materials include one or more selected from alkali metal-containing oxide-based materials and alkali metal-containing polyanion materials, the alkali metal being one or more alkali metals selected from sodium and / or potassium, optionally in combination with lithium. Particular active positive electrode materials contain lithium as a trace alkali metal component, i.e., the amount of lithium is less than 50% by weight, preferably less than 10% by weight, and ideally less than 5% by weight of the total alkali metal content.

[0106] The most preferred positive electrode active materials are compounds of the general formula: A 1±δ M 1 V M 2 W M 3 X M 4 Y M 5 Z O 2-c [In formula: A is one or more alkali metals selected from sodium, potassium and lithium; M 1 comprises one or more redox active metals having an oxidation state of +2; M 2 contains metals with oxidation states greater than 0 and less than or equal to +4; M 3 contains a metal in the oxidation state +2; M 4 contains metals with oxidation states greater than 0 and less than or equal to +4; M 5 contains a metal in the oxidation state +3; 0≦δ≦1; V is >0; W is ≧0; X is ≧0; Y is ≧0; At least one of W and Y is >0; Z is ≧0; C is in the range 0≦c<2; V, W, X, Y, Z and C are selected to maintain electrochemical neutrality].

[0107] For the avoidance of doubt, the term "one or more alkali metals selected from sodium, potassium and lithium" should be taken to include Na, K, Li, Na+K, Na+Li, K+Li, and Na+K+Li.

[0108] Ideally, metal M 2 comprises one or more transition metals, preferably selected from manganese, titanium and zirconium; M 3 is preferably one or more selected from magnesium, calcium, copper, tin, zinc and cobalt; M 4 comprises one or more transition metals preferably selected from manganese, titanium and zirconium; and M 5is preferably one or more selected from aluminum, iron, cobalt, tin, molybdenum, chromium, vanadium, scandium and yttrium. Cathode active materials having any crystalline structure can be used, preferably O3 or P2 or derivatives thereof, although strictly speaking it is also possible for the cathode material to have a heterogeneous structure comprising a mixture of phases, i.e. composed of several different crystalline forms.

[0109] Highly preferred active cathode materials include transition metal-containing compounds containing sodium and / or potassium, with sodium transition metal nickelate compounds being particularly preferred. Particularly preferred examples include alkali metal layered oxides, single and mixed phase O3, P2 and P3 alkali metal layered oxides, alkali metal-containing polyanion materials, oxymetallates, Prussian blue analogues and Prussian white analogues. Specific examples include O3 / P2-A 0.833 Ni 0.317 Mn 0.467 Mg 0.1 Ti 0.117 O2, O3-A 0.95 Ni 0.3167 Mn 0.3167 Mg 0.1583 Ti 0.2083 O2, P2 type A 2 / 3 Ni 1 / 3 Mn 1 / 2 Ti 1 / 6 O2, P2-A 2 / 3 (Fe 1 / 2 Mn 1 / 2 )O2, P'2-A 2 / 3 MnO2, P3 or P2-A 0.67 Mn 0.67 Ni 0.33 O2, A3V2(PO4)3, AVPO4F, AVPO4F, A3V2(PO4)3A3V2(PO4)2F3, A3V2(PO4)2F3, A x Fe y Mn y (CN)6.nH2O(0≦x, y, z≦2; 0≦n≦10), O3, P2 and / or P3-A x Mn y Ni zO2 (0≦x≦1 and 0≦y, z≦1). A2Fe2(SO4)3, A2Ni2SbO6 and A3Ni2SbO6, where "A" in these compounds is one or more alkali metals selected from Li, Na and K, preferably Na and / or K, and most preferably Na.

[0110] Advantageously, the alkali metal ion cell according to the invention may use an electrolyte in any form, i.e., a solid, liquid or gel composition, suitable examples include: 1) a liquid electrolyte, e.g., >0-10 molar alkali metal salt, e.g., NCO, in one or more solvents, preferably selected from ethylene carbonate (EC), diethyl carbonate (DEC), propylene carbonate (PC) (preferably as a mixture of EC:DEC:PC in a ratio of 1:2:1 wt / wt), gamma butyrolactone (GBL), sulfolane, diglyme, triglyme, tetraglyme, dimethylsulfoxide (DMSO), dioxolane and mixtures thereof. aPF6, NaBF4, sodium bis(oxalate) (NaBOB), sodium triflate (NaOTf), LiPF6, LiAsF6, LiBF4, LiBOB, LiClO4, LiFSi, LiTFSi, Li-triflate and mixtures thereof, all with or without a diluent such as HFE (1,1,2,2-tetrafluoroethyl 2,2,3,3-tetrafluoropropyl ether) or D2 (1,1,2,2-tetrafluoroethyl 2,2,2-trifluoroethyl ether); 2) gel electrolytes based on any one of the following matrix materials used alone or in combination with each other; or 3) solid electrolytes, such as Na3Zr2Si2PO 12 NASICON type such as Na3PS4 or Na3SbS4, sulfide type such as Na2B 10 H 10 -Na2B 12 H 12or β-alumina systems such as Na2O.(8-11)Al2O3, or related β"-alumina systems such as Na2O.(5-7)Al2O3. Known electrolyte additives such as cyclic 1,3-propanediol sulfate (PCS), P123 surfactant, tris(trimethylsilyl) phosphite (TMSP), tris(trimethylsilyl) borate (TMSB), 1-propene 1,3 sultone, 1,3-propane sultone, and binders such as polyvinylidene fluoride (PVDF), polyvinylidene fluoride-hexafluoropropylene (PVDF-HFP), poly(methyl methacrylate) (PMMA), sodium carboxymethylcellulose (CMC), and styrene-butadiene rubber (SBR) can also be included in the electrolyte.

[0111] When the metal ion cell is a sodium ion cell, the electrolyte is preferably one or more solvents selected from ethylene carbonate (EC), diethyl carbonate (DEC), propylene carbonate (PC). The electrolyte may include a combination of propylene carbonate (PC) with ethylene carbonate (EC) and / or diethyl carbonate (DEC). Ideally, the electrolyte includes a mixture of ethylene carbonate (EC), diethyl carbonate (DEC), and propylene carbonate (PC).

[0112] Optional electrolyte additives may also be included, such as one or more of cyclic 1,3-propanediol sulfate (PCS), P123 surfactant, and tris(trimethylsilyl)borate (TMSB). The electrolyte may also include a sodium metal salt selected from NaPF6, NaBF4, preferably NaPF6.

[0113] In another aspect, the present invention provides a sodium-ion cell comprising a cathode electrode, an anode electrode, and an electrolyte, wherein the anode electrode comprises a carbon-containing anode material as defined herein.

[0114] In one embodiment, the electrolyte comprises one or more selected from the following: >0-10 molar sodium metal salts selected from NaPF6, NaBF4, sodium bis(oxalate) (NaBOB), sodium triflate (NaOTf), preferably in one or more solvents selected from ethylene carbonate (EC), diethyl carbonate (DEC), propylene carbonate (PC), dimethyl carbonate (DMC), ethyl methyl carbonate (EMC), gamma butyrolactone (GBL), sulfolane, diglyme, triglyme, tetraglyme, dimethyl sulfoxide (DMSO), dioxolane, and mixtures thereof; NASICON type electrolytes, sulfide based electrolytes, hydride based electrolytes, β-alumina based electrolytes, and β″-alumina based electrolytes.

[0115] When the metal ion cell is a sodium ion cell, the anode electrode according to the present invention preferably further comprises a polymer binder. Typically, the polymer binder is selected from polyvinylidene fluoride (PVDF), styrene-butadiene rubber (SBR), and carboxymethyl cellulose (CMC). Preferably, the polymer binder comprises carboxymethyl cellulose (CMC). Highly preferably, the polymer binder comprises a mixture of styrene-butadiene rubber (SBR) and carboxymethyl cellulose (CMC).

[0116] When the metal-ion cell is a sodium-ion cell, the anode electrode according to the invention ideally comprises a carbon-containing anode material according to the invention (A), one or more polymeric binders (B), and one or more conductive additives (C). Such a mixture is typically mixed with an aqueous or non-aqueous solvent (e.g., water or N-methylpyrrolidone (NMP)) and then disposed as a layer or film on one or more surfaces of the anode current collector using techniques such as doctor blading or slot die techniques.

[0117] A:B:C are typically present in a weight ratio of 80-98:1-19:1-19, ideally 90-98:1-9:1-9. When the polymeric binder comprises polyvinylidene fluoride (PVDF), A:B:C are preferably present in a weight ratio of about 92:6:2. When the polymeric binder comprises preferably carboxymethylcellulose (CMC), most preferably a mixture of styrene-butadiene rubber (SBR) and carboxymethylcellulose (CMC), A:B:C are preferably present in a weight ratio of about 95:3.5:1.5.

[0118] The one or more conductive additives (C) can include one or more of carbon black, carbon nanotubes, graphene, acetylene black, and carbon nanofibers. Preferably, the one or more conductive additives include carbon black, such as TIMCAL Super C65.

[0119] The sodium-ion cell disclosed herein can also include an anode (negative) electrode including an anode current collector, and / or a cathode (positive) electrode including a cathode current collector. The cathode current collector, the anode current collector, or both the cathode current collector and the anode current collector can be formed of aluminum or an aluminum alloy (e.g., an alloy of aluminum with one or more of Mg, Mn, Cr, Zn, Si, Fe, and Ni). Preferably, the anode current collector includes an aluminum current collector. Highly preferably, both the cathode current collector and the anode current collector include an aluminum current collector. Alternatively, copper, magnesium, carbon paper / foil / substrate, and tin may also be used as current collector materials.

[0120] Preferably, the anode current collector also includes one or more carbon-containing layers formed on one or more surfaces of the anode current collector prior to the first charge cycle of the sodium-ion cell. Such layers can ideally comprise amorphous carbon (e.g., carbon black such as TIMCAL Super C65) having a thickness of about 10 Angstroms to about 1000 μm.

[0121] Alternatively, the anode current collector disclosed herein does not include one or more carbon-containing layers on one or more surfaces of the anode current collector prior to the first charge cycle of the sodium-ion cell. Thus, the anode current collector is in an "initial state" prior to the first charge cycle of the sodium-ion cell. When used herein with respect to the current collector, the phrase "initial state" means that the current collector is in an "as-prepared" state prior to the first charge cycle of the sodium-ion cell. In other words, the anode current collector is substantially pure material from its source of formation, absent impurities (e.g., surface oxide layers, etc.). Thus, the anode current collector is not coated with one or more carbon-containing layers (as described above), conventional active materials, binders, or the like.

[0122] The sodium-ion cells disclosed herein can also include a separator located between the cathode and anode current collectors. Polyolefin separators are preferred.

[0123] In another aspect, the present invention provides a lithium-ion cell comprising a cathode electrode, an anode electrode, and an electrolyte, wherein the anode electrode comprises a carbon-containing anode material as defined herein.

[0124] In one embodiment, the electrolyte comprises LiPF6, LiAsF6, LiBF4, LiBOB, LiClO4, LiFSi, LiTFSi, Li-triflate, and mixtures thereof, and one or more solvents selected from ethylene carbonate (EC), diethyl carbonate (DEC), propylene carbonate (PC), dimethyl carbonate (DMC), ethyl methyl carbonate (EMC), gamma butyrolactone (GBL), sulfolane, diglyme, triglyme, tetraglyme, dimethyl sulfoxide (DMSO), dioxolane, and mixtures thereof.

[0125] It should be noted that the surface engineered carbon-containing materials of the present invention are not only excellent anode materials, but also offer additional commercial advantages. The first advantage relates to improved moisture sensitivity: due to their extremely low levels of open microporosity, the surface engineered carbon-containing anode materials of the present invention adsorb significantly less atmospheric moisture upon exposure than primary carbon-containing materials that do not have an engineered surface. This not only facilitates the handling of Applicant's anode materials during anode fabrication, but also reduces the moisture content of the resulting anode coatings and finished cells.

[0126] A second unexpected advantage is related to the improved viscosity of the electrode slurry containing the carbon-containing anode material according to the invention. The viscosity of the electrode slurry should not be overlooked during cell manufacturing, as it makes a significant difference in the smooth running of the process and the quality control of the resulting electrodes. The electrode materials (active material, binder, and additives) are typically mixed and dispersed in an organic or aqueous solvent so that they can be coated onto the current collector. In the coating process, the solvent evaporates, leaving behind the dry components. Insufficient viscosity can cause the slurry to flow too much, which can cause the edges of the coating to slip; on the other hand, an overly viscous slurry causes process problems because the slurry does not flow smoothly enough. This has a negative impact on the quality of the dried coating. Typically, electrode materials with a smaller surface area require less solvent to achieve a given optimal viscosity. This is advantageous from a cost perspective. Thus, as a result of the smaller microporous surface area, the surface-engineered carbon-containing anode material according to the invention exhibits a lower viscosity for the same solids content, which results in a smoother surface morphology and a purer surface chemistry. Cost savings can be achieved by using less solvent to achieve good quality electrodes. Detailed Description Proposed model for the structure of carbon-containing anode materials according to the invention FIG. 1 shows a schematic diagram of a grain of a carbon-containing material in a pristine state, comprising a core comprising a primary carbon-containing material. FIG. 1 further shows a schematic diagram of a grain of a surface-engineered carbon-containing anode material 10 according to the present invention (i.e., in a non-pristine state), comprising a core comprising a primary carbon-containing material 1 and an outer surface 15 comprising a carbonized material 35 chemically bonded onto the primary carbon-containing material 1. More specifically, FIG. 1 helps to explain the proposed mechanism by which a surface-engineered carbon-containing anode material 10 according to the present invention can exhibit a significant reduction in open micropore surface area while recording a minimal reduction in overall surface area. FIG. 1 can also help to explain how a surface-engineered carbon-containing anode material 10 according to the present invention has a greater moisture absorption resistance compared to a pristine carbon-containing material comprising a core comprising a primary carbon-containing material 1.

[0127] 1, a representative grain of pristine carbon-containing material including a core comprising a primary carbon-containing material 1 having open porosity can have an irregular and non-uniform outer surface 15 formed with a plurality of open mesopores 20 and a plurality of open micropores 25. After the pristine carbon-containing material including a core comprising a primary carbon-containing material 1 has been processed, for example, according to the method of the present invention, a non-uniform and incomplete, extremely thin layer 30 of particles of carbonized material 35 (e.g., derived from a secondary carbon-containing material) is deposited on the outer surface 15 of the pristine carbon-containing material including a core comprising a primary carbon-containing material 1 to produce a surface engineered carbon-containing anode material 10 according to the present invention.

[0128] As shown in Figure 1, the entrances of many of the open micropores 25 are blocked by adhering particles of carbonized material 35 forming an extremely thin layer 30. In Figure 1, the blocked micropores are shown as 55 on the surface engineered carbon-containing anode material 10. It will be appreciated that since the uneven and incomplete layer 30 is extremely thin, it is highly unlikely to be sufficient to obscure / block the entrances of the larger mesopores 20, but that the layer 30 may instead partially coat the interior of the mesopores, thereby slightly reducing the surface area of ​​these pores.

[0129] The increased hydrophobicity of the surface engineered carbon-containing anode material according to the present invention can also be explained by the fact that the number of water molecules 40 a that can enter the blocked or obstructed micropores 55 is reduced compared to the number of water molecules 40 that can enter the open micropores 25 of the pristine primary carbon-containing material 1, making the surface engineered carbon-containing material 10 according to the present invention more moisture resistant than the non-surface engineered material. EXAMPLES

[0130] General Method for Preparing Templated Carbon Cores for Carbon-Containing Anode Materials According to the Invention In a typical process, glucose is converted to magnesium gluconate (Mg(CH 11 The carbon-containing starting material and the pore-forming material-containing starting material are carbonized by mixing the carbon-containing starting material with magnesium gluconate (Mg(CH)2·xH2O) and subjecting the resulting mixture to initial carbonization at 600 °C for 60-120 minutes. 11 By using O7)2·xH2O), MgO was formed in situ as a pyrogen.

[0131] The resulting carbonized material is then milled to a D50 of approximately 9 μm and desalted in boiling (approximately 100° C.) aqueous HCl solution having a concentration of 1.0-2.0 M for 60-120 min. After rinsing the powder with deionized water, the desalted carbonized material is pyrolyzed at 1450° C. for 60 min under flowing argon to obtain the templated porous carbon material. Specific details of these steps are shown in Table 1. General Method for Preparing Non-Templated Carbon Cores for Carbon-Containing Anode Materials Not According to the Invention In a typical process, carbon-containing starting material such as biochar, carbohydrates or phenolic resins is carbonized at 600 °C for 60-120 min. The carbonized material is then milled to a D50 of approximately 9 μm and, if necessary, demineralized in boiling (approximately 100 °C) aqueous HCl solution having a concentration of 1.0-2.0 M for 60-120 min. After rinsing the powder with deionized water, the demineralized carbonized material is pyrolyzed under flowing argon at 1100-3000 °C for 60 min to obtain non-templated carbon. Specific details of these steps are shown in Table 1. General Method for Preparing Activated Carbon Cores for Carbon-Containing Anode Materials According to the Invention Two types of commercially available activated carbon were used here, the details of which are shown in Table 3. In the case of "activated carbon B," this material has an iodine uptake of about 610 mg / g and a D of about 8 μm. 50 had the following characteristics: General method for surface treatment of cores for carbon-containing anode materials according to the invention In a typical process, a core comprising one or more primary carbon-containing materials according to the invention in particulate form is treated with one or more secondary carbon-containing materials at 200-950°C for 30-120 minutes. Ideally, the treatment process is carried out in a predominantly inert gas atmosphere. More ideally, one or more secondary carbon-containing materials are provided in the required concentrations (as described above), with the gaseous secondary carbon-containing material preferably being provided in a carrier gas (preferably an inert carrier gas) and the liquid secondary carbon-containing material preferably being provided in a carrier solvent or other carrier liquid.

[0132] A preferred treatment process is to use an inert gas (e.g., argon) and a benzene ring of formula C n H 2n+2The secondary carbon-containing material is used in the examples in Table 1 (where applicable). The treatment is preferably carried out at a temperature of about 830° C. for 30 minutes as shown in Table 1. Details of the carbon-containing anode materials tested are shown in Table 1 below:

[0133] [Table 1]

[0134] [Table 2]

[0135] Determining the size of primary carbon-containing materials Size measurements of the primary hard carbon-containing materials (core materials) were performed using laser diffraction and scanning electron microscopy. The results showed that experimental materials 1-6 yielded particle size distributions as shown below:

[0136] [Table 3]

[0137] When the one or more primary carbon-containing materials include one or more carbon composites represented by (carbon)-X as disclosed herein, the particle size distribution may differ from the above in some cases. This is because the size of some composites may be in the nanoscale range. Thus, in one embodiment, the particle size distribution of the primary carbon-containing material of the present invention is about 1 nm to about 30 μm, preferably about 1 nm to about 20 μm.

[0138] To the best of the applicant's knowledge, the surface treatment of the present invention does not substantially change the particle size distribution of the primary carbon-containing material. In one example of the present invention, the mass deposit of secondary carbon-containing material was found to be very low (2.2±0.8% by weight per 30 minutes of deposition). Therefore, the particle size distribution of the primary carbon-containing material after surface treatment (i.e., the carbon-containing anode material according to the present invention) can be considered to be substantially similar to the particle size distribution of the primary carbon-containing material before surface treatment. Analysis of products using XPS: Determination of surface carbon, oxygen and inorganic content (atomic %) The amount of carbon, oxygen and inorganic content (atomic %) present on the surface of experimental materials 1-6 and control experimental materials 1-9 was measured using XPS with the analytical specifications summarized below in Table 2. The results of the surface carbon, oxygen and inorganic content are shown in Table 3.

[0139] [Table 4]

[0140] Analysis of products using BET: BET surface area (m 2 / g) BET analysis was performed using a Micromeritics Gemini VII 2390 surface area analyzer with nitrogen as the adsorbent at liquid nitrogen temperature. All samples were degassed overnight at 250 °C under flowing nitrogen prior to analysis. The results are shown in Table 3. Analysis of products using BET: BET micropore surface area (m 2 / g) From the volume of gas adsorbed in the material, by applying the model, it is possible to calculate and estimate the surface area of ​​the micropores accessible to the gas (open micropores, i.e. micropores at the surface of the carbon-containing anode material) per gram of carbon-containing anode material (or pristine hard carbon-containing material, in the case of control samples). This was achieved by a "t-plot" analysis. A typical t-plot consists of the amount of gas adsorbed at standard temperature and pressure versus the statistical thickness (nm) of Harkins and Jura according to the Harkins and Jura thickness equation (t=[13.99 / (0.034-log(p / p°))]^0.5). The difference between the external surface area and the BET (total) surface area is the estimated micropore surface area. The results obtained are shown in Table 3 with the corresponding plots in the figures. Analysis of products using SAXS Small angle X-ray scattering (SAXS) measurements were performed using a Cu k α Measurements were performed on a Xenocs Xeuss 2.0 equipped with a 1000 nm source. The scattering signal was recorded using a Pilatus 300k detector mounted on a translation stage. Measurements were performed at multiple sample-detector distances, with the results presented here measured at 0.339(2) m. The sample was mounted on a 0.9 mm thick metal sample holder, sealed between adhesive Kapton windows, and measured for 10 min. The sample chamber was kept under vacuum during the measurements. A mask was applied to the collected 2D images, which were then integrated radially as a function of q to generate 1D intensity vs. q plots. These were then corrected for transmission and background scattering. Analysis of products using XRD To confirm that the desired target material had been prepared, to establish the phase purity of the product material, and to determine the types of impurities present, analysis by X-ray diffraction techniques was performed using a Siemens D5000 powder diffractometer. From this information it is possible to determine the unit cell parameters.

[0141] The general XRD operating conditions used for the analysis of the precursor electrode materials are as follows: Slit size: 1mm, 1mm, 0.1mm Range: 2θ=5°~60° X-ray wavelength = 1.5418Å (Cu Kα) Speed: 0.5~2 seconds / step Increment: 0.015°~0.05° The results obtained are shown as plots in the figures.

[0142] [Table 5]

[0143] General conclusions from the product analyses shown in Table 3 The analytical results of the products from the materials in Table 1 are summarized in Table 3. In particular, Table 3 shows the analytical results obtained using BET N2 adsorption, XPS and SAXS techniques. Average Pore Size The average pore size results obtained for materials with templated hard carbon cores unexpectedly showed larger average pore sizes (Å) than comparative materials with non-templated hard carbon cores. For example, templated material 5 resulted in a pore size of 12.5±1.3 Å compared to 8.8±1.3 Å for control material 5, which was prepared under the same conditions as templated material 5 (but without the use of a pore-forming agent to effect templating). Thus, the hard carbon templating process appears to increase the average pores by approximately 40%.

[0144] However, it is important that the pyrolysis temperatures are the same when making this comparison, since the SAXS derived pore radius depends significantly on pyrolysis temperature, with higher pyrolysis temperatures resulting in larger pores. Micropore specific surface area and micropore volume The micropore specific surface areas (m 2 / g) and micropore volume (cm 3The results for the specific surface area and micropore volume (µm / g) of the surface-treated comparative non-templated hard carbon cores were unexpectedly lower than those of the surface-treated comparative non-templated hard carbon cores. For example, this is observed by comparing the results obtained for experimental materials 4 and 5 with those of control material 4. XPS Data The XPS data obtained for experimental materials 1-5 were found to be consistent with the methods used to prepare these templated hard carbon materials. For example, higher levels of carbon content (i.e., 94 atomic % or more) and lower levels of inorganic content (i.e., 3 atomic % or less) were observed in the materials that had been subjected to a desalting step compared to the material that had not been subjected to a desalting step (i.e., experimental material 3).

[0145] Additionally, experimental materials 1, 4, and 5, which were produced using boiling 2.0 M HCl in the desalting step, appeared to exhibit higher levels of carbon content and lower levels of inorganic content compared to experimental material 2, which was produced using sonication with 1.0 M HCl in the desalting step. The results observed for oxygen content followed a similar trend. XRD data Figures 12-16 show the XRD plots obtained for experimental materials 1-5. Each plot shows evidence of a hard carbon structure as evidenced by the broad peaks shown at 20-25°. The plots also show the presence of a sharp peak at 40-45°, indicative of MgO arising in the templating process. Mg(CH 11 The presence of MgO resulting from the use of O7)2·xHO was also confirmed by XRD analysis of the impurities obtained from the desalting, as shown in Figure 22. The impurities are shown in Figure 23. The XRD shows the presence of a sharp peak at 40-45° similar to those observed in Figures 12-16. Electrochemical results Anodes containing carbon-containing materials made according to the present invention are prepared by solution casting of a slurry containing the experimental carbon-containing material (described above), a binder, and a conductive additive.

[0146] Polyvinylidene fluoride (PVDF) and styrene-butadiene rubber / carboxymethyl cellulose (SBR / CMC) are suitable binders. N-methyl-2-pyrrolidone (NMP) alone, water alone, or a mixture of NMP and water can be employed as the solvent. C65 TM A conductive additive such as carbon (Timcal) (RTM) was used in the slurry.

[0147] The experimental carbon-containing materials (mentioned above), binder, and conductive additives were mixed and homogenized in a weight ratio of A:B:C, where A, B, and C are 80-98; 1-19; and 1-19, respectively. Specifically, for the slurries containing PVDF and SBR / CMC, ratios of 92:6:2 and 95:3.5:1.5 were used, respectively.

[0148] The slurry was then cast onto a collector foil. In particular, pristine or carbon-coated aluminum foil was found to be suitable. The cast slurry was then heated until most of the solvent evaporated to form an electrode film. The anode electrode was then further dried under reduced pressure at 60-200°C, after which the anode electrode was calendered to the desired thickness. Cell Test In the half-cell test, an experimental carbon-containing anode electrode is paired with a disk of sodium metal as the reference and counter electrodes. Glass fiber GF / A is used as the separator, and a suitable electrolyte is also employed. Any suitable Na-ion electrolyte can be used, preferably one or more salts such as NaPF6, NaAsF6, NaClO4, NaBF4, NaSCN, and Na triflate in combination with one or more organic solvents such as EC, PC, DEC, DMC, EMC, glymes, esters, acetates, etc. Other additives such as vinylene carbonate and fluoroethylene carbonate can also be incorporated. A preferred electrolyte composition includes 0.5M NaPF6 / EC:PC:DEC. The cells shown in Tables 4 and 5 were constructed using the electrolyte compositions shown below:

[0149] [Table 6]

[0150] The chemical abbreviations used above are summarized below:

[0151] [Table 7]

[0152] All cells were allowed to rest for 24 hours before cycling. In the three-electrode test, the carbon-containing anode material according to the invention was used as the negative electrode, the standard oxide material was used as the positive electrode, and one sheet of sodium was used as the reference electrode, with all three electrodes wetted with the same electrolyte. As separators, two polyethylene membranes with a thickness of 24.5 um were used. The half cells were tested using the constant current cycling technique, and the full cells, including the three-electrode full cells, were tested using the constant current-constant voltage technique. The cells were cycled at a given current density between pre-set voltage limits. Commercial battery cyclers from MTI Inc. (Richmond, CA, USA) or Maccor (Tulsa, Oklahoma, USA) were used. During charging, alkali ions are inserted into the carbon-containing anode material. During discharging, alkali ions are desorbed from the anode and reinserted into the cathode active material.

[0153] [Table 8]

[0154] [Table 9]

[0155] Not according to the invention - no surface treatment Electrochemical testing of anode control materials 8 and 9 (no surface treatment) containing non-templated hard carbon - full cell Table 5 shows the electrochemical performance data for cell 019, which used anode control material 8, and cell 020, which used anode control material 9. Both anode control materials 8 and 9 relate to non-templated hard carbon that does not have a surface treatment according to the present invention.

[0156] Using control material 8 in cell 019, a reversible desodium capacity of 158 mAh / g can be achieved, along with an irreversible specific capacity of 46.4 mAh / g and a first cycle coulombic efficiency of 77.3%.

[0157] Using control material 9 in cell 020, a reversible desodium capacity of 174 mAh / g can be achieved, along with an irreversible specific capacity of 45.0 mAh / g and a first cycle coulombic efficiency of 79.4%. Electrochemical testing of anode control materials 4 and 5 (with surface treatment) containing non-templated hard carbon - full cell Table 5 shows the electrochemical performance data for cells 014 and 015 using anode control material 4, and cell 016 using anode control material 5. Both anode control materials 4 and 5 relate to non-templated hard carbons that have been surface treated according to the present invention. Cells 014 and 016 use electrolyte 1, and cell 015 uses electrolyte 2.

[0158] Using control material 4 in cell 014, a reversible desodium capacity of 322 mAh / g can be achieved with an irreversible specific capacity of 31.1 mAh / g and a first cycle coulombic efficiency of 91.2%. Using electrolyte 2 versus electrolyte 1 in cell 014, cell 015 achieved a reversible desodium capacity of 313 mAh / g with an irreversible specific capacity of 27.3 mAh / g and a first cycle coulombic efficiency of 92.0%.

[0159] Using control material 5 in cell 016, a reversible desodium capacity of 309 mAh / g can be achieved, along with an irreversible specific capacity of 40.5 mAh / g and a first cycle coulombic efficiency of 88.4%. Electrochemical testing of anode control materials 6 and 7 (with surface treatment) containing non-templated hard carbon - half cell (vs. Na+ / Na) When Anode Control Material 6 was used in Cell 017, a reversible desodium capacity of 284 mAh / g was achieved along with an irreversible specific capacity of 41.6 mAh / g and a first cycle Coulombic efficiency of 87.2%.

[0160] When anode control material 7 was used in cell 018, a reversible desodium capacity of 258 mAh / g was achieved along with an irreversible specific capacity of 54.2 mAh / g and a first cycle coulombic efficiency of 82.6%. Electrochemical Testing of Anode Control Material 2 (with Surface Treatment) Containing Activated Hard Carbon - Half Cell (vs. Na+ / Na) When Anode Control Material 2 was used in Cell 012, a reversible desodium capacity of 148 mAh / g was achieved along with an irreversible specific capacity of 465.0 mAh / g and a first cycle coulombic efficiency of 24.2%. Electrochemical Testing of Anode Control Material 3 (without Surface Treatment) Containing Activated Hard Carbon - Half Cell (vs. Na+ / Na) When Anode Control Material 3 was used in Cell 013, a reversible desodium capacity of 71 mAh / g was achieved along with an irreversible specific capacity of 185.1 mAh / g and a first cycle coulombic efficiency of 27.8%. According to the invention - surface treatment Electrochemical testing of anode materials 2-6 (with surface treatment) containing templated hard carbon - full cell As can be seen in Table 5, the first cycle coulombic efficiencies and anode reversible specific capacities of full cells 001–009, featuring the surface-treated templated carbon anode materials 1–5, were unexpectedly and significantly and consistently higher than those observed for the control full cells 014–016, featuring the control non-templated surface-treated carbon materials 4–5.

[0161] Specifically, full cells 001-009 achieved anodic specific reversible capacities of 338-407 mAh / g compared to anodic specific reversible capacities of 309-322 mAh / g observed for control full cells 014-016.

[0162] It should be noted that the true plating-free reversible specific capacity of surface-treated templated hard carbon according to the present invention exceeds 400 mAh / g, and the first cycle coulombic efficiency is typically greater than 92%. Figure 42 shows an anode electrode containing surface-treated templated hard carbon according to the present invention removed from a full cell with an anode reversible specific capacity >400 mAh / g. After discharging to 1.0 V and removal, no evidence of plating, i.e., saturation or dendrite formation, was observed. It is also worth noting that for practical and safety reasons, the anode specific capacity is often underutilized in commercial full cells. Thus, for all cycle life data shown in Figures 54-58, the anode operated at approximately 350 mAh / g, i.e., at least 50 mAh / g was unused. The utilization of the anode can be controlled by controlling the mass and capacity balance of the full cell. This can be conveniently achieved by selecting the appropriate coat weights of the anode and cathode electrodes.

[0163] It is noted that the control full cells 014–016 achieved first cycle coulombic efficiencies of 88.4–91.2%, which are comparable to the first cycle coulombic efficiencies of 88.2–93.6% seen for the experimental full cells 002–009 featuring anode carbon-containing materials 1–5.

[0164] Cell 011, featuring the control non-surface-treated templated carbon material 1, did not exhibit high anode reversible specific capacity or first cycle coulombic efficiency compared to those observed in full cells 001-009, featuring the templated surface-treated carbon anode materials 1-5, or full cells 014-016, featuring the control non-templated surface-treated carbon materials 4-5.

[0165] Applicants understand that this observed lower efficiency may result from the fact that the control templated non-surface treated carbon material 1 exhibits a high micropore surface area of ​​18.8941 m2 / g, as shown in Table 5. That is, control material 1 was not surface treated.

[0166] Additionally, cell 019, featuring the control non-templated, non-surface treated carbon material 8, and cell 020, featuring the control non-templated, non-surface treated carbon material 9, both exhibited lower anode reversible specific capacities than full cells 001-009, 011, and 014-016, and lower first cycle coulombic efficiencies than full cells 001-009 and 014-016.

[0167] Thus, an advantage attributable to the present invention, and particularly to the use of the templated primary carbon-containing material of the present invention in combination with the surface treatment of the present invention, is that an increase in both the coulombic efficiency and the anode reversible specific capacity is observed. Thus, it is shown that the templated primary carbon-containing material of the present invention, when surface treated in accordance with the present invention, achieves high anode reversible specific capacity and high first cycle coulombic efficiency.

[0168] Cell 004, featuring templated surface treated carbon material 3, exhibited a lower first cycle coulombic efficiency than cells 001 and 005-009. Applicant understands that this is likely because the carbon content as determined by XPS in Table 3 was lower for material 3 than for materials 1 and 4-5. Thus, when the primary carbon-containing material comprises a templated porous carbon material, a carbon content of greater than 92% is highly desirable to achieve a first cycle coulombic efficiency of greater than 83%.

[0169] Cell 009 exhibited a first cycle coulombic efficiency of 93.6%, which was the highest observed result in Table 5. Applicants believe this effect stems from the use of surface-treated templated carbon material 4 in combination with an electrode formulation having an active material loading of 95 wt% and SBR / CMC as a binder additive and water as a slurry solvent. In comparison, Cell 007, which contains the same templated surface-treated carbon material (Run 4) but has a different electrode formulation having an active material loading of 92 wt% and PVDF as a binder additive and NMP as a slurry solvent, exhibits a lower first cycle coulombic efficiency under comparable electrochemical test conditions.

[0170] As can be seen from Figure 57, the surface-treated non-templated hard carbon retains about 95% of the initial capacity and energy after 110 cycles of +C / 5 charge and -C / 5 discharge between 1.0 and 4.05 V, showing stable cycling behavior.

[0171] To calculate the full cell capacity and energy retention expressed in %, the absolute capacity and energy values ​​of all the proceeding cycles are normalized based on the absolute capacity and energy values ​​of the cell at the fifth cycle, i.e., the first ±C / 5 cycle after four initial ±C / 10 formation cycles. In this specification, the formation cycle refers to the cycle in which the SEI layer is formed on the surface of the anode electrode, after which the formed full cell is subsequently degassed, vacuum sealed again, and returned to the cycler for further testing. Example 3 (According to the Invention) Electrochemical testing of anode material 7 (with surface treatment) containing activated carbon - half cell (vs. Na+ / Na) As can be seen from Table 5, the first cycle coulombic efficiency and anode reversible specific capacity of half-cell 010, featuring surface-treated activated carbon material 6, were unexpectedly and consistently higher than those observed for control half-cell 013, featuring non-surface-treated activated carbon material 2. Specifically, half-cell 010 achieved an anode specific reversible capacity of 291 mAh / g, compared to the 71 mAh / g observed for control half-cell 013. Additionally, half-cell 010 achieved a first cycle coulombic efficiency of 87.2%, compared to the 27.8% first cycle coulombic efficiency seen for half-cell 013.

[0172] However, these advantages are not evident at 1000m, as confirmed by Half Cell 012. 2 This was not achieved in half-cells featuring surface-treated activated carbon with a specific surface area of ​​1.0 mAh / g or greater. Specifically, in control half-cell 012, an anode specific reversible capacity of 148 mAh / g was observed along with a first cycle coulombic efficiency of 24.2%.

[0173] Thus, an advantage resulting from the present invention, and in particular from the use of the activated carbon of the present invention in combination with the surface treatment of the present invention, is that an increase in both the coulombic efficiency and the anode reversible specific capacity is observed. [Explanation of symbols]

[0174] 1 Primary carbon-containing materials 10 Surface engineered carbon-containing anode materials 15 Outer surface 20 Open mesopores 25 Open Micropores 30 Ultra-thin layer 35 Carbonized materials 40 Water molecules that can enter open micropores 40a Water molecules that can enter blocked micropores 55 Blocked Micropores

Claims

1. 1. A carbon-containing anode material capable of inserting and deintercalating alkali metal ions, comprising: a) a core comprising one or more primary carbon-containing materials selected from i) a templated porous carbon material and / or ii) an activated carbon material, wherein the activated carbon material has a surface area of ​​about 200 m as determined using nitrogen gas BET analysis. ２ / g ~ approx. 1000m ２ / g specific surface area of ​​the core; and b) an exterior surface comprising one or more carbonized materials chemically bonded onto one or more primary carbon-containing materials; and a carbon structure comprising: Determined using nitrogen gas BET analysis ２ / g to 5m ２ / g of the carbon-containing anode material.

2. The carbon-containing anode material has a 0 m ２ / g to 5m ２ 10. The carbon-containing anode material of claim 1, having a specific surface area of ​​0.1 wt. / g.

3. 10. The carbon-containing anode material of claim 1, wherein the carbon-containing anode material has an average pore radius of 9 Å or greater as determined using small-angle x-ray scattering.

4. 10. The carbon-containing anode material of claim 1, wherein the templated porous carbon material is derived from a carbon-containing starting material and then treated by an end-templating process.

5. 10. The carbon-containing anode material of claim 1, wherein the one or more primary carbon-containing materials are derived by pyrolysis of plant-based materials, animal-derived materials, hydrocarbon materials, carbohydrate materials, and other carbon-containing organic materials.

6. 10. The carbon-containing anode material of claim 1, wherein the one or more primary carbon-containing materials comprise one or more carbon composites represented by (carbon)-X, where X is one or more elements selected from the group consisting of antimony, tin, phosphorus, sulfur, boron, aluminum, gallium, indium, germanium, lead, arsenic, bismuth, titanium, molybdenum, selenium, tellurium, silicon, carbon, and magnesium; or X is one or more oxides of elements selected from the group consisting of antimony, tin, phosphorus, sulfur, boron, aluminum, gallium, indium, germanium, lead, arsenic, bismuth, titanium, molybdenum, selenium, tellurium, silicon, carbon, and magnesium.

7. 10. The carbon-containing anode material of claim 1, wherein the carbonized material is derived from one or more secondary carbon-containing materials selected from organic materials and hydrocarbon materials.

8. 10. The carbon-containing anode material of claim 1 comprising a minimum of 92.0 atomic percent carbon on the outer surface.

9. 10. The carbon-containing anode material of claim 1, wherein the one or more primary carbon-containing materials have a particle size of from about 1 nm to about 30 μm.

10. 1. A process for preparing a carbon-containing anode material capable of inserting and deintercalating alkali metal ions, comprising: a) a core comprising one or more primary carbon-containing materials selected from i) a templated porous carbon material and / or ii) an activated carbon material, wherein the activated carbon material has a surface area of ​​about 200 m as determined using nitrogen gas BET analysis. ２ / g ~ approx. 1000m ２ providing said core having a specific surface area of ​​1 / g; and b) contacting the core with one or more secondary carbon-containing materials at a temperature of up to 950°C, thereby producing a carbon-containing anode material having an outer surface comprising one or more carbonized materials chemically bonded to one or more primary carbon-containing materials, the carbon-containing anode material having an outer surface of 0 m as determined using nitrogen gas BET analysis; ２ / g to 5m ２ providing said carbon-containing anode material having an open micropore specific surface area of ​​1 / g; The preparation process comprising:

11. The templated porous carbon material of step a) is (i) providing one or more carbon-containing starting materials together with one or more pore-forming materials and / or one or more compounds used to derive one or more pore-forming materials; (ii) optionally, first heating the components provided in step (i), preferably at a temperature of about 60 to 950°C; (iii) optionally purifying the product obtained in step (ii); and (iv) pyrolyzing the components provided in step (i), or the optional products obtained in step (ii) or step (iii), preferably at a temperature of from about 600 to about 3000°C; The process of claim 10, wherein the compound is formed by

12. 12. The process of claim 11, wherein step i) comprises a physical mixture, wherein the one or more carbon-containing starting materials are selected from hydrocarbon and carbohydrate materials, and the one or more pore-forming substances and / or the one or more compounds used to derive the one or more pore-forming substances are selected from salts, inorganic compounds, and organometallic compounds.

13. 13. The process of claim 12, wherein the one or more carbon-containing starting materials comprise a carbohydrate material and the one or more pore-forming materials and / or the one or more compounds used to derive the one or more pore-forming materials comprise a magnesium salt.

14. The process of any of claims 11 to 13, wherein step iii) comprises using alkaline and / or acidic conditions.

15. A sodium-ion cell comprising a cathode electrode, an anode electrode, and an electrolyte, wherein the anode electrode comprises the carbon-containing anode material of any of claims 1 to 9.

16. 16. The sodium-ion cell of claim 15, wherein the anode electrode further comprises a polymer binder, the polymer binder comprising carboxymethyl cellulose (CMC).

17. A lithium-ion cell comprising a cathode electrode, an anode electrode, and an electrolyte, wherein the anode electrode comprises the carbon-containing anode material according to any one of claims 1 to 9.

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