Abstract: The present application discloses an artificial graphite, a preparation method therefor and the use thereof. A method for preparing an artificial graphite of an embodiment of the present application comprises the following step: subjecting a graphite raw material to a heat treatment to obtain the artificial graphite, wherein an environmental atmosphere for the heat treatment is at least one gas of air and carbon dioxide or a mixed gas of at least one gas of air and carbon dioxide and a chemically inert gas; and during the heat treatment, the graphite raw material is in a static state. The method realizes at least modifying a surface of the graphite raw material by controlling the heat treatment conditions for the graphite raw material, such that the prepared artificial graphite has an appropriately low compaction rebound capacity, a high and stable compacted density, and a good cycling performance.

Abstract: A preparation method of an artificial graphite includes heat-treating a graphite raw material to obtain artificial graphite, where an ambient atmosphere of the heat treatment is a mixed gas including a gas that is at least one of oxygen or water vapor and including a chemically inert gas, and, during the heat treatment, the graphite raw material is in a motion state.

Abstract: This application discloses a secondary battery including a positive electrode plate and a negative electrode plate, wherein the positive electrode plate comprises a positive electrode current collector and a positive electrode film disposed on a surface of the positive electrode current collector and comprising a positive active material, the negative electrode plate comprises a negative electrode current collector and a negative electrode film disposed on a surface of the negative electrode current collector and comprising a negative active material. The positive active material comprises one or more of lithium-containing phosphates with olivine structure and modified compounds thereof, and a resistance R of the negative electrode plate satisfies: 3.0 m??R?7.0 m?.

Abstract: This application provides a negative electrode plate, including an active layer 1 and an active layer 2. The active layer 1 contains an active material 1, and the active layer 2 contains an active material 2. A powder OI value of the active material 1 falls in a range of 8 to 32, and a powder OI value of the active material 2 falls in a range of 2 to 7. A gram capacity of the active material 1 falls in a range of 290 to 350 mAh/g, and a gram capacity of the active material 2 falls in a range of 350 to 368 mAh/g. A ratio ? of the powder OI value between the active material 1 and the active material 2 falls in a range of 2.00 to 6.25.

Abstract: The present application relates to a secondary battery, a process for preparing the same and an apparatus containing the secondary battery. The negative electrode film of the secondary battery comprises a first negative electrode film and a second negative electrode film; the first negative electrode film is disposed on at least one surface of the negative electrode current collector and comprises a first negative electrode active material; and the second negative electrode film is disposed on the first negative electrode film and comprises a second negative electrode active material, the first negative electrode active material comprises natural graphite and the first negative electrode active material satisfies: 0.60?S1?0.85; and the second negative electrode active material comprises artificial graphite. The secondary battery according to the present application has both better low-temperature rate performance and longer high-temperature cycle life while having a higher energy density.

Abstract: The present application relates to a secondary battery, a process for preparing the same and an apparatus containing the secondary battery.

Abstract: The present application discloses an artificial graphite, a secondary battery, a preparation method and an apparatus. The artificial graphite includes secondary particles formed by agglomeration of primary particles, the artificial graphite having a volume average particle size Dv50, denoted as A, the artificial graphite through powder compaction under a pressure of 2000 kg having a volume average particle size Dv50, denoted as B, wherein A and B satisfies: B/A?0.85. Using the artificial graphite provided by the present application can greatly reduce the cyclic expansion of the secondary battery.

Abstract: This application relates to a secondary battery and an apparatus including the secondary battery. Specifically, the secondary battery of this application includes a negative electrode plate, where the negative electrode plate includes a negative current collector and negative film layers where the negative film layers include a first negative film layer and a second negative film layer, the first negative film layer is disposed on at least one surface of the negative current collector and includes a first negative active material, and the second negative film layer is disposed on the first negative film layer and includes a second negative active material; the first negative active material includes natural graphite, and the second negative active material includes artificial graphite; the first negative active material satisfies 4.0?COI1?7.0; and the second negative active material satisfies 2.2?COI2?4.2.

Abstract: The present application discloses a negative electrode active material and a method for preparing the same, a secondary battery, and an apparatus including the secondary battery. The negative electrode active material includes a core and a coating layer covering the surface of the core, the core includes artificial graphite, the coating layer includes amorphous carbon, and the particle size uniformity of the negative electrode active material is from 0.25 to 0.45.

Abstract: The present application relates to a secondary battery, a process for preparing the same and an apparatus containing the secondary battery.

Abstract: Disclosed are a composite graphite material, a method for preparing the same, a negative electrode sheet, a secondary battery, a battery module, a battery pack, and an electrical apparatus. The composite graphite material comprises a bulk particle and a cladding layer located on at least a partial surface of the bulk particle, the bulk particle is a secondary particle formed by aggregation of more than two primary particles, the bulk particle comprises artificial graphite, the cladding layer comprises amorphous carbon, and an air oxidation temperature T0 of the composite graphite material is from 630° C. to 730° C. The composite graphite material in the present application can enable the secondary battery to not only have a high energy density, but also have significantly improved fast charging performance and low-temperature power performance.

Abstract: Provided are a modified graphite and a preparation method thereof, a carbon-coated negative active material and a preparation method thereof, a negative electrode plate, a secondary battery, a battery module, a battery pack, and an electrical device. The preparation method of a modified graphite includes the following steps: (S10) providing a graphite substrate; and (S20) heat-treating the graphite substrate in a micro-oxidizing atmosphere to obtain the modified graphite, where the micro-oxidizing atmosphere includes a reactive gas, and the reactive gas is one or more selected from CO2, O2, and O3. The preparation method of a carbon-coated negative active material includes the following steps: (S100) providing a negative active material substrate; and (S200) heat-treating the negative active material substrate and a carbonaceous precursor in a micro-oxidizing atmosphere to obtain the carbon-coated negative active material, where the micro-oxidizing atmosphere includes a reactive gas.

Abstract: This application discloses a negative-electrode active material and a preparation method thereof, a secondary battery, and a battery module, a battery pack, and an apparatus that include such secondary battery. The negative-electrode active material includes a core and a coating layer covering at least part of a surface of the core, where the core includes artificial graphite, the coating layer includes amorphous carbon, a volume-based particle size distribution of the negative-electrode active material satisfies Dv99?24 ?m, a volume-based median particle size Dv50 of the negative-electrode active material satisfies 8 ?m?Dv50?15 ?m, Dv99 is a particle size corresponding to a cumulative volume distribution percentage of the negative-electrode active material reaching 99%, and Dv50 is a particle size corresponding to a cumulative volume distribution percentage of the negative-electrode active material reaching 50%.

Abstract: This application discloses a secondary battery and an apparatus containing the secondary battery. The secondary battery comprises a positive electrode plate comprising a positive active material and a negative electrode plate comprising a negative active material. The negative active material comprises a first material and a second material, the first material comprises artificial graphite, and the second material comprises natural graphite. The positive active material comprises one or more of layered lithium transition metal oxides and modified compounds thereof, and a smoothness L of a surface of the negative electrode film away from the negative electrode current collector satisfies: 40?L?50; or the positive active material comprises one or more of lithium-containing phosphates with olivine structure and modified compounds thereof, and a smoothness L of a surface of the negative electrode film away from the negative electrode current collector satisfies: 45?L?55.

Abstract: An artificial graphite and a preparation method thereof, a secondary battery containing the artificial graphite, and an electric apparatus are provided. The artificial graphite includes secondary particles and satisfies A?0.5, where A is a ratio of a powder compacted density of the artificial graphite at 2 t pressure to a particle size by volume Dv1 of the artificial graphite. The secondary battery provided in this application can have low cyclic volume swelling while maintaining high energy density.

Abstract: An artificial graphite material A. The artificial graphite material A is secondary particles are provided. In some embodiments, a surface roughness ?A of the artificial graphite material A satisfies 6??A?12. This application further provides an artificial graphite material B. The artificial graphite material B is primary particles, where a surface roughness ?B of the artificial graphite material B satisfies 2.5??B?5. This application further provides a secondary battery containing the artificial graphite material A and/or the artificial graphite material B and an electric apparatus. The secondary battery provided by this application can have high energy density and long service life.

Abstract: This application provides a negative electrode active material and a preparation method thereof. The negative electrode active material may be self-embedded graphite composed of graphite A and graphite B, where the surface of the graphite A may have a tenon structure, the surface of the graphite B may have a mortise structure, the tenon structure of the graphite A and the mortise structure of the graphite B may be mutually embedded, and a hydrogen bond may be formed between the tenon structure of the graphite A and the mortise structure of the graphite B.

Abstract: This application relates to a secondary battery, a process for preparing the same and an apparatus containing the secondary battery. In particular, the negative electrode plate comprises a negative current collector and a negative electrode film, wherein the negative electrode film comprises a first negative electrode film and a second negative electrode film, the first negative electrode film is comprises a first negative electrode active material, and the particle size uniformity of the first negative electrode active material is from 0.4 to 0.6; the second negative electrode film comprises a second negative electrode active material, and the particle size uniformity of the second negative electrode active material is from 0.25 to 0.45, and a ratio of the particle size uniformity of the first negative electrode active material to the particle size uniformity of the second negative electrode active material is from 1.05 to 1.9.

Abstract: Embodiments provide a secondary battery and an apparatus containing the secondary battery. The secondary battery includes a negative electrode plate. The negative electrode plate includes a copper-based current collector and a negative electrode film layer disposed on at least one surface of the copper-based current collector and including a negative electrode active material, and the negative electrode active material includes graphite. The negative electrode plate satisfies Tx?25, where Tx is as defined in the specification.

Abstract: A method for preparing a modified graphite includes performing crushing on coal-based needle coke to obtain a first material, performing shaping fine powder removal on the first material to obtain a second material, performing heat treatment on the second material in a reaction kettle and then cooling the second material after the heat treatment to room temperature to obtain a third material, and performing graphitization on the third material in a graphitization furnace and then cooling the third material after the graphitization to room temperature to obtain the modified graphite.