Description:FIELD OF THE INVENTION
001 The present invention relates to a negative electrode active material for lithium-ion batteries, specifically to a material comprising artificial graphite. This material incorporates a blend of primary particles, secondary particles, graphite fines, or combinations thereof. It is designed to improve quick-charging performance, enhance conductivity, and low-temperature application capabilities.

BACKGROUND OF THE INVENTION
002 The performance of lithium-ion batteries is largely influenced by the graphite anode materials. Graphite is the ideal anode material due to its ability to reversibly intercalate lithium ions, its low-voltage operational window, and its stable structural properties. However, the gravimetric/volumetric energy density, quick-charge capability, structure stability, and long cycle life are critical to particle size distribution, morphology, surface area, crystallographic orientation, and other microstructural characteristics.

003 Artificial graphite, synthesized through carbon precursor carbonization and particle engineering followed by high-temperature graphitization (>2500°C), exhibits excellent electrochemical performance in lithium-ion batteries. Nevertheless, it is always better to follow best engineering practices when designing materials, such as long-life cycle, quick charge, high electrode density, higher discharge capacity, and broader suitability for advanced battery applications.

004 To address these challenges, post-graphitization blending is employed, combining primary particles with secondary particles. Primary particles enhance first-cycle efficiency and electrode compaction, while secondary particles improve structural integrity and create ion transport pathways, facilitating faster lithium-ion diffusion and enabling rapid-charging capabilities. Although the blending of primary and secondary particles is documented in prior art, existing solutions have low conductivity for low-temperature operation and high-rate charging, particularly in demanding applications such as battery electric vehicles (BEVs) and fast-charging portable devices.

005 To resolve these limitations, the invention introduces graphite fines into the post-graphitization blend. The graphite fines act as nanoscale bridges, filling interparticle voids and enhancing electrical conductivity. This improves rapid-charging performance and boosts conductivity at low temperatures. Furthermore, the method enhances manufacturing efficiency and cost-effectiveness without requiring significant modifications to existing production processes.

OBJECTS OF THE INVENTION
006 The objective of the present invention is to provide a negative electrode that includes artificial graphite particles, wherein these particles contain primary particles, secondary particles, and graphite fines after post graphitization.

007 Another objective of the present disclosure is to provide a negative electrode that includes artificial graphite particles, wherein these particles contain primary particles and secondary particles after post graphitization.
SUMMARY OF THE INVENTION
008 This summary is provided to introduce a selection of concepts in a simplified form that are further described below in the detailed description section. This summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used to determine the scope of the claimed subject matter. The difficulties and drawbacks of previous approaches are addressed in the present invention.

009 Aspects of the invention relate to negative electrode material and its method of preparation. The negative electrode is cost-effective and overcomes existing challenges resulting in overall enhanced battery performance.

010 An aspect of the present invention is to provide a negative electrode that includes artificial graphite particles, which comprise blends of primary particles, secondary particles, and graphite fines after post graphitization.

011 Another aspect of the present invention is to provide a negative electrode that includes artificial graphite particles, which comprise blends of primary particles and secondary particles after post-graphitization.

012 In another aspect of the present invention, the artificial graphite includes 60 wt% to 85 wt% secondary particles, 10 wt% to 30 wt% primary particles, and 0–10 wt% graphite fines, based on the total weight percentage of the artificial graphite particles.

013 In another aspect of the present invention, the artificial graphite includes 70 wt% to 85 wt% secondary particles and 15 wt% to 30 wt% primary particles based on the total weight percentage of the artificial graphite particles.

014 In yet another aspect of the present invention, the artificial graphite particles have a specific surface area (BET) ranging from 0.8 m²/g to 2.5 m²/g, a tap density of 0.90 g/cm³ to 1.30 g/cm³, electrode porosity in the range of 5% to 35%, and a powder orientation I(002)/(I110) and I(004)/(I110) of 2.6 to 71.

015 This, together with the other aspects of the present invention, along with the various features of novelty that characterized the present disclosure, is pointed out with particularity in the claims annexed hereto and forms a part of the present invention. For a better understanding of the present disclosure, its operating advantages, and the specified objective attained by its uses, reference should be made to the accompanying descriptive matter in which there are illustrated exemplary embodiments of the present invention.

DESCRIPTION OF THE DRAWINGS
016 The advantages and features of the present invention will become better understood with reference to the following detailed description taken in conjunction with the accompanying drawings:
017 Fig. 1 illustrates the graph, which provides X-ray diffraction patterns for calculating the Orientation Index (OI) of Artificial Graphite Blends. This data pertains to the analysis of the orientation index of the artificial graphite powder sample.
018 Fig. 2 illustrates the [D90 − D50)/Dmax] and (D90−D10)/D50 ratio range of artificial graphite particles, a parameter used to characterize particle size distribution.
019 Fig. 3 illustrates the quantitative degree of circularity of the primary particles (as measured via image analysis).
020 Fig. 4 illustrates the SEM images of primary and secondary particles, as well as graphite fines (individually).
021 Fig. 5 illustrates the SEM images of artificial graphite containing primary and secondary particles, as well as graphite fines (Blend).
DETAILED DESCRIPTION
022 The exemplary embodiments described herein detail for illustrative purposes are subjected to many variations. It should be emphasized, however, that the present invention is not limited to a negative material electrode and its method of preparation as disclosed. It is understood that various omissions and substitutions of equivalents are contemplated as circumstances may suggest or render expedient, but these are intended to cover the application or implementation without departing from the spirit or scope of the present invention.

023 Unless otherwise specified, the terms used in the specification and claims have the meanings commonly used in the field of negative electrode material and method of preparation involved therein. Specifically, the following terms have the meanings indicated below.

024 Embodiments are provided thoroughly and fully convey the scope of the present disclosure to the person skilled in the art. Numerous details are set forth relating to specific components, and methods, to provide a complete understanding of embodiments of the present disclosure. It will be apparent to the person skilled in the art that the details provided in the embodiments should not be construed to limit the scope of the present disclosure. In some embodiments, known processes, well-known apparatus or structures, and well-known techniques are not described in detail.

025 The terminology used, in the present disclosure, is only to explain a particular embodiment and such terminology shall not be considered to limit the scope of the present disclosure. As used in the present disclosure, the forms "a,” "an," and "the" may be intended to include the plural forms as well, unless the context suggests otherwise. The terms "comprises," "comprising," “including,” and “having,” are open-ended transitional phrases and therefore specify the presence of stated features, integers, steps, operations, elements, modules, units, and/or components, but do not forbid the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. The order of steps disclosed in the method and process of the present disclosure is not to be construed as necessarily requiring their performance as described or illustrated. It is also to be understood that additional or alternative steps may be employed.

026 As used herein, “combinations thereof” is inclusive of one or more of the recited elements, optionally together with a like element not recited, e.g., inclusive of a combination of one or more of the named components, optionally with one or more other components not specifically named that have essentially the same function. As used herein, the term “combination” is inclusive of blends, mixtures, alloys, reaction products, and the like.

027 The term “Powder orientation” of artificial graphite refers to the alignment of graphite particles or their crystalline layers during processing, influencing directional properties like electrical/thermal conductivity and mechanical strength in applications such as battery electrodes.

028 The term “Specific surface area (BET)” of artificial graphite refers to the total surface area of the graphite particles as measured by the Brunauer-Emmett-Teller (BET) method, typically expressed in square meters per gram (m²/g).

029 The term “Tap density” of artificial graphite refers to the mass of the graphite powder per unit volume after it has been tapped or compacted, typically measured in grams per cubic centimeter (g/cm³), and is an indicator of how tightly the particles pack together.

030 The term “cohesion strength” refers to the internal force that holds the particles of a material together, resisting separation due to attractive forces between them, influencing the material's structural integrity and performance, expressed in newton per meter (N/m).

031 The term “Primary particles degree of circularity” refers to the measurement of how closely the shape of a primary particle approximates a perfect circle, often quantified as a ratio or index. It indicates the smoothness and roundness of individual particles, which can affect properties like flowability and packing density in materials such as artificial graphite.

032 The term “Electrode porosity” of artificial graphite refers to the proportion of void spaces or pores within the graphite material in an electrode, which affects its surface area, ion conductivity, and overall performance in battery applications.

033 The term "Capacity of an electrode" refers to the amount of electrical charge (measured in milliampere hours, mAh or Ah/kg) that an electrode can store and deliver per unit mass of its active material, essentially defining how much electricity the electrode can hold based on its weight; it is often expressed as "specific capacity" to indicate the capacity per gram of the electrode material. It is typically measured in mAh/g or Ah/kg (milliampere hours per gram).

034 The term (wt%) refers to weight percentage and is the mass of a component in a mixture expressed as a percentage of the total mass of the mixture. It is used to represent the concentration of a substance in a mixture based on its weight relative to the overall weight.

035 The term “First cycle efficiency" of an electrode refers to the ratio of the discharge capacity during the very first charge-discharge cycle of a battery to the charge capacity during that same cycle, essentially indicating how much of the initial charge is effectively stored and can be later retrieved during the first discharge, often used in the context of lithium-ion batteries where a significant portion of the initial charge can be lost due to irreversible side reactions during the first cycle.

036 The term “negative electrode” here refers to the anode material used in a lithium battery, which is typically made of a carbonaceous material such as graphite, silicon, or combinations thereof. It absorbs lithium ions from the electrolyte during the charging process.

037 In one embodiment of the present invention, a graphitization process is carried out by placing binderless mesophase carbon (BMC) coke into a high-temperature furnace. The furnace is heated to 2600 degrees Celsius under an inert argon atmosphere, and the temperature is maintained for 4 to 8 hours to facilitate the crystallographic alignment of the carbon structure. After the desired time, the graphitized material is gradually cooled to room temperature. The resulting product exhibits enhanced crystallinity, making it suitable for applications requiring high electrical conductivity and thermal stability.

038 In an embodiment of the present invention, a negative electrode includes artificial graphite particles, which contain primary particles, secondary particles, and graphite fines after post-graphitization.

039 In an embodiment of the present invention, a negative electrode includes artificial graphite particles, which contain primary particles and secondary particles after post-graphitization

040 In an embodiment of the present invention, the artificial graphite includes 60 wt% to 85 wt% secondary particles, 10 wt% to 30 wt% primary particles, and 0–10 wt% graphite fines, based on the total weight percentage of the artificial graphite particles.

041 In an embodiment of the present invention, the artificial graphite includes 70 wt% to 85 wt% secondary particles and 15 wt% to 30 wt% primary particles, based on the total weight of the artificial graphite particles.

042 In an embodiment of the present invention, the artificial particles include 60 wt% to 85 wt%, preferably 60 wt% to 80 wt%, preferably 65 wt% to 75 wt% of secondary particles.

043 In an embodiment of the present invention, the artificial particles include 10 wt% to 30 wt%, preferably 15 wt% to 30 wt%, preferably 15 wt% to 25 wt% of primary particles.

044 In an embodiment of the present invention, artificial particles include 0 wt% to 10 wt%, preferably 1 wt% to 7 wt%, preferably 0 wt% to 5 wt% of graphite fines.

045 In one embodiment of the present invention, artificial graphite particles are blended using a ribbon blender. The ribbon blender comprises a U-shaped trough equipped with two counter-rotating helical ribbons. During the blending process, primary particles, secondary particles, and graphite fines are loaded into the blender in predetermined proportions. The opposing rotation of the helical ribbons generates a three-dimensional mixing action, ensuring homogeneous dispersion of the particles and consistent material properties throughout the blend. This method produces a blended material with enhanced flowability and improved packing density, thereby optimizing its electrochemical performance in battery electrode formulations. Alternatively, other blending equipment such as a V-blender, tumbling mixer, or high-shear mixer may be substituted for the ribbon blender, provided the selected equipment achieves comparable uniformity and consistency in the blended graphite particles. The choice of blending apparatus may depend on factors such as material properties (e.g., particle size distribution, friability) and process requirements (e.g., throughput, energy input).

046 In one embodiment, the artificial graphite particles exhibit an I₀₀₄/I₁₁₀ XRD intensity ratio ranging from 2.0 to 7.2, with a preferred range of 2.7 to 5.0. This ratio is measured using X-ray diffraction (XRD) with Cu-Kα radiation (λ = 1.5406 Å) at a scan rate of 2 - 5° per minute via a Rigaku Smart Lab X-ray diffractometer. A lower I₀₀₄/I₁₁₀ ratio represents the higher isotropic or lower anisotropic advantageous to improve the uniformity in electrochemical performance, enhanced charge and discharge rates, and overall battery performance.

047 In another embodiment, the cohesion strength of the artificial graphite particles ranges from 30 N/m to 100 N/m, with a preferred range of 40 N/m to 80 N/m. Cohesion strength is measured using a powder shear tester per ASTM D7891. This property ensures mechanical stability during electrode calendaring and reduces the risk of short circuits, critical for maintaining structural integrity during battery manufacturing.

048 In a further embodiment, the particle size distribution (PSD) of the artificial graphite particles is characterized by (D₉₀ − D₁₀)/D₅₀ ratio: 0.7–1.1, preferably 0.9 to 1.0 and (D₉₀ − D₅₀)/Dmax ratio: 0.1 to 0.5, preferably 0.1 to 0.3. PSD is measured using a laser diffraction particle size analyzer. A uniform distribution minimizes electrode cracking, thereby enhancing the mechanical and electrochemical properties of the electrode.

049 In yet another embodiment, the tap density of the artificial graphite particles ranges from 0.90 g/cm³ to 1.30 g/cm³, preferably in the range of 1.00 g/cm³ to 1.20 g/cm³. Tap density is measured using a tap density meter as per ASTM B527. Higher tap density improves volumetric energy density, boosting overall battery capacity.

050 In another embodiment, the specific surface area (BET) of the artificial graphite particles ranges from 0.8 m²/g to 2.5 m²/g, preferably in the range of 1.2 m²/g to 2.0 m²/g. BET surface area is measured via nitrogen adsorption.

051 In another embodiment, the oxidation onset temperature of the artificial graphite particles ranges from 600 degrees Celsius to 800 degrees Celsius, preferably 700 degrees Celsius to 800 degrees Celsius in a synthetic air atmosphere, measured by thermogravimetric analysis room temperature to 1000 degrees Celsius with a heating rate of 10 degrees Celsius per minute. A higher oxidation onset temperature improves safety under accidental air ingress conditions at high-temperature applications.

052 In a further embodiment, the powder orientation ratio [I(002)/I (110)] ranges from 60 to 200, preferably 68 to 150, calculated from XRD peak intensities. A higher ratio improves isotropic ratios and has the advantage of a quick charge.

053 In a further embodiment, the powder orientation ratio [I(004)/I (110)] ranges from 2 to 7.8, preferably 2.8 to 7, calculated from XRD peak intensities.

054 In another embodiment, the degree of granulation of secondary particles exceeds 75%, preferably 80% to 95%, with a D₅₀ of 10 to 25 μm, preferably 15–20 μm. Granulation is quantified via SEM image analysis. Improved granulation enhances porosity, facilitating ion transport and electrochemical performance.

055 In one embodiment, the primary particles have a degree of circularity of 0.75 to 0.99, preferably 0.85 to 0.95, and a D₅₀ of 7 to 15 μm, preferably 9 to 12 μm. Circularity is measured via dynamic image analysis. Higher circularity improves tap density, which in turn enhances the energy density.

056 In another embodiment, graphite fines with a D₅₀ of 1 to 7 μm, preferably 2 to 5 μm are included to optimize electrode conductivity and structure.

057 In another embodiment, the degree of porosity of the electrode ranges from 5% to 35%, preferably 10% to 25%, measured via mercury intrusion porosimeter. Controlled porosity enhances ion conductivity and charge/discharge efficiency, supporting high-performance energy storage

058 Referring to Fig. 1, the graph illustrates the I(004)/I(110) and I(002)/I(110) Orientation Index (OI) values for an artificial graphite powder sample. These indices are critical indicators of crystallographic alignment, reflecting the degree of preferential orientation of the graphite’s crystal planes along specific crystallographic directions. The ratios quantify the alignment of (004) and (002) lattice planes relative to the (110) plane, which directly correlates with the material isotropy. The empirical data in Fig. 1 provides insights into the crystallographic structure of the graphite and validates the effectiveness of the post-graphitization treatment employed during sample preparation. By analyzing these OI values, the quality and alignment of the graphite powder can be rigorously assessed, ensuring its suitability for energy storage systems and other electrochemical applications.

059 Referring to Fig. 2 illustrates the [D90 − D50)/Dmax] ratio range for artificial graphite particles, a key metric characterizing the particle size distribution within the material. This ratio is calculated using three critical particle size parameters: D90: The particle size below which 90% of the sample’s volume lies, D50: The median particle size (50th percentile), and Dmax: The maximum particle size observed in the sample. The [(D90 − D50)/Dmax] ratio quantifies the dispersion of particle sizes. A lower ratio indicates a narrow size distribution, reflecting high particle uniformity, while a higher ratio signifies a broader distribution with increased size variability. In the context of artificial graphite, this ratio directly correlates with critical material properties such as flowability, electrochemical reactivity, and compaction behavior—factors essential for optimizing negative electrode performance in batteries. Precise control over particle size distribution via this ratio enables tailored improvements in packing density, surface area, and electrode stability. The range displayed in Fig. 2 defines the optimal particle size distribution for the artificial graphite in the present invention, ensuring enhanced efficiency and longevity in battery applications.

EXAMPLES

060 The present invention is further explained in the form of the following examples. However, it is to be understood that the following examples are merely illustrative and are not to be taken as limitations upon the scope of the invention.

061 Example 1: Preparation of Artificial Graphite: Blending of Primary and Secondary Particles.
Artificial graphite consists of a blend, following post-graphitization, made up of 70 wt% secondary particles, 30 wt% primary particles, with no graphite fines.

062 Example 2: Preparation of Artificial Graphite: Blending of Primary and Secondary Particles
Artificial graphite consists of a blend, following post-graphitization, made up of 50 wt% secondary particles and 50 wt% primary particles, with no graphite fines.

063 Example 3: Preparation of Artificial Graphite: Blending of Primary and Secondary Particles
Artificial graphite consists of a blend, following post-graphitization, made up of 80 wt% secondary particles and 20 wt% primary particles, with no graphite fines.

064 Example 4: Preparation of Artificial Graphite: Blending of Primary and Secondary particles with Graphite Fines
Artificial graphite consists of a blend, following post-graphitization, made up of 90 wt% secondary particles, 5 wt% primary particles, and 5 wt% graphite fines.

065 Example 5: Preparation of Artificial Graphite: Blending of Primary and Secondary particles with Graphite Fines
Artificial graphite consists of a blend, following post-graphitization, made up of 57 wt% secondary particles, 40 wt% primary particles, and 3 wt% graphite fines.

066 Table 1 Clearly outlines the different examples, each using various blends of primary particles, secondary particles & also graphite fines with a focus on D50 (µm), BET (m²/g), Tap Density (g/cm³), Powder Orientation OI (004/110 and 002/110), Capacity (mAh/g), and First Cycle Efficiency (%)

Material Description
Properties
D50 (µm) BET (m2/g) Tap Density (gcm3) Powder orientation OI (004/110 and 002/110) Capacity (mAh/g) First cycle efficiency (%)
Example 1 12 1.2 1.17 3.5 and 120 354 93.0
Example 2 13.4 1.1 1.2 3.8 and 150 354 93.7
Example 3 13.0 1.11 1.09 3.2 and 105 355 94.1
Example 4 12.0 1.32 1.09 3.1 and 95 350 94.8
Example 5 11.0 1.45 1.18 4.0 and 170 353 94.4

067 Table 1 outlines the properties of five artificial graphite formulations, each comprising distinct blends of primary particles, secondary particles, and graphite fines. The median particle size (D50) ranges from 11.0 µm (Example 5) to 13.4 µm (Example 2), with smaller D50 values (e.g., Example 5) suggesting improved particle packing density and reactivity. The BET surface area varies between 1.1 m²/g (Example 2) and 1.45 m²/g (Example 5), where the higher surface area of Example 5 implies greater availability of active reaction sites. Tap density ranges from 1.09 g/cm³ (Example 4) to 1.32 g/cm³ (Example 4), reflecting minor differences in particle packing efficiency.

068 The orientation index (OI) values for crystallographic planes (004/110 and 002/110) demonstrate enhanced crystallographic alignment in Example 5, with OI values of 4.0 and 170, respectively. Capacity measurements reveal the highest energy storage potential in Examples 2 and 3 (354–355 mAh/g), while Example 4 exhibits the lowest capacity (350 mAh/g). First-cycle efficiency (FCE%) ranges from 93.0% (Example 1) to 94.8% (Example 4), with Example 4 showing superior initial charge/discharge performance.

069 Collectively, the data illustrates the interplay between particle composition (primary/secondary agglomerates and fines), structural properties (particle size, surface area, tap density, crystallographic alignment), and electrochemical performance (capacity, FCE%). These results highlight the tailored optimization of artificial graphite formulations for specific functional requirements.

070 Table 2 clearly outlines the primary particles, secondary particles, and graphite fines individually, without blending, with a focus on D50 (µm), BET (m²/g), Tap Density (g/cm³), Powder Orientation OI (004/110 and 002/110), Capacity (mAh/g), and First Cycle Efficiency (%).
Material Properties
D50 (µm) BET (m2/g) Tap Density (gcm3) Powder orientation OI (004/110 and 002/110) Capacity (mAh/g) First cycle efficiency-FCE (%)
Primary 9.5 1.7 1.11 7.3 and 212 356 95.0
Secondary particles 14.8 1.1 1.1 2.7 and 71 354 93.6
Graphite Fines 5.8 5.1 0.65 3.2 and 75 340 93.2

071 Table 2 summarizes the properties of primary particles, secondary particles, and graphite fines. The D50 values (µm), representing median particle sizes, are 9.5 µm for primary particles, 14.8 µm for secondary particles, and 5.8 µm for graphite fines. This indicates that primary particles are moderately sized, secondary particles are comparatively larger, and graphite fines are significantly smaller.

072 The BET surface area (m²/g)—a measure of specific surface area—is highest for graphite fines at 5.1 m²/g, far exceeding the values for primary (1.7 m²/g) and secondary particles (1.1 m²/g). This suggests that graphite fines possess a greater active surface area for reactions.

073 Tap density (g/cm³) values reveal that primary particles have the highest packing efficiency at 1.11 g/cm³, followed by secondary particles (1.1 g/cm³) and graphite fines (0.65 g/cm³). The lower tap density of graphite fines implies a looser particle arrangement.

074 The Powder Orientation Index (OI), reflecting crystallographic alignment, is highest in primary particles at 7.3 (004/110) and 212 (002/110), indicating superior structural order that may enhance conductivity. Secondary particles exhibit significantly lower OI values (2.7 for 004/110 and 71 for 002/110), while graphite fines lack recorded OI data, suggesting a minimal crystalline structure. Regarding capacity (mAh/g), primary particles deliver the highest energy storage potential at 356 mAh/g, slightly outperforming secondary particles (354 mAh/g). Graphite fines trail at 340 mAh/g.

075 Finally, First Cycle Efficiency (FCE%) is highest for primary particles (95.0%), followed by secondary particles (93.6%) and graphite fines (93.2%). This gradual decline in efficiency correlates with particle type, highlighting primary particles as the most efficient in initial charge/discharge cycles.

076 While the foregoing describes various embodiments of the disclosure, other and further embodiments of the disclosure may be devised without departing from the basic scope thereof. The invention is not limited to the described embodiments, versions, or examples, which are included to enable a person having ordinary skill in the art to make and use the invention when combined with information and knowledge available to the person having ordinary skill in the art.

ADVANTAGES OF THE INVENTION
077 The technical advantages offered by the present invention are as follows:
078 The present invention provides new insights into the post-graphitization process of graphite blends.
079 The present invention introduces a new graphite blend anode material for quick charge and discharge applications.
080 The present invention offers a new graphite blend designed for long life cycles.
081 The present invention presents a new graphite blend suitable for low-temperature applications.
 
, Claims:1. A negative electrode material comprising artificial graphite particles, wherein the artificial graphite particles comprise primary particles, secondary particles, and graphite fines.

2. The negative electrode material as claimed in claim 1, wherein the artificial graphite particles comprise
I. 60 wt% to 85 wt% secondary particles with respect to the total weight of the electrode material;
II. 10 wt% to 30 wt% primary particles with respect to the total weight of the electrode material; and
III. 0 wt% to 10 wt% graphite fines, with respect to the total weight of the electrode material.

3. The negative electrode material as claimed in claim 1, wherein the artificial graphite particles have powder orientation (OI) I (004)/I (110) in the range of 2.0 to 6.1.

4. The negative electrode material as claimed in claim 1, wherein the artificial graphite particles have a cohesion strength of 30 N/m to 100 N/m.

5. The negative electrode material as claimed in claim 1, wherein the artificial graphite particles have a particle size distribution ratio (D90−D10)/D50 in the range of 0.7 to 1.1.

6. The negative electrode material as claimed in claim 1, wherein the artificial graphite particles have a particle size distribution ratio (D90−D50)/Dmax in the range of 0.1 to 0.3.

7. The negative electrode material as claimed in claim 1, wherein the artificial graphite particles have a tap density of 0.90 g/cm³ to 1.30 g/cm³.

8. The negative electrode material as claimed in claim 1, wherein the artificial graphite has a BET specific surface area in the range of 0.8 m²/g to 2.5 m²/g.

9. The negative electrode material as claimed in claim 1, wherein the artificial graphite exhibit an onset of oxidation in oxygen atmosphere within the range of 400 to 700 degrees Celsius.

10. The negative electrode material as claimed in claim 1, wherein the primary particles have a degree of circularity ranging from 0.75 to 1.

11. The negative electrode material as claimed in claim 1, wherein the graphite fines have a D50 particle size in the range of 1 μm to 7 μm.

12. The negative electrode material as claimed in claim 1, wherein the secondary particles have a D50 particle size in the range of 10 μm to 25 μm.

13. The negative electrode material as claimed in claim 1, wherein the primary particles have a D50 particle size in the range of 7 μm to 15 μm.

14. The negative electrode material as claimed in claim 1, wherein the artificial graphite has electrode porosity in the range 5% to 35%.