Abstract: A silicon-carbon composite material, a preparation method thereof, and a secondary battery are provided. The silicon-carbon composite material includes a silicon-carbon composite core and a carbon coating layer coated on the silicon-carbon composite core, and multiple closed pores are dispersed in the silicon-carbon composite core. The preparation method includes steps of (I) a surface modification treatment of a high-molecular polymer, (II) a preparation of a nano-silicon dispersion, (III) a preparation of a first precursor, (IV) a preparation of a second precursor, and (V) carbon coating. The closed pores in the silicon-carbon composite core can effectively alleviate the significant volume effect of silicon generated during lithium intercalation and deintercalation, and the combination of the silicon-carbon composite core and the carbon coating layer can ensure structural stability and high strength of the material.

Abstract: A silicon-based anode material and a preparation method thereof are provided. The silicon-based anode material includes a silicon-based core and a coating layer, the silicon-based core includes nano silicon and a lithium-containing silicon oxide, and the coating layer at least includes a polymer layer with —Si—O—Si— bonds. The preparation method of a silicon-based anode material includes (I) preparing a silicon-based core; and (II) coating a polymer layer. The silicon-based anode material includes high initial Coulombic efficiency and initial lithium intercalation capacity. The polymer layer with —Si—O—Si— bonds in the coating layer is insoluble in water, which avoid problems such as slurry sedimentation and poor coating performance, making the silicon-based anode material have good processing performance.

Abstract: A lithium-doped silicon oxide composite anode material with high initial Coulombic efficiency and a preparation method are provided, which relates to the field of anode materials for lithium batteries. The material includes nano-silicon, lithium silicate and a conductive carbon layer. A diffraction peak intensity of Li2Si2O5(111) with 2? being 24.7±0.2° in an XRD pattern of the lithium-doped silicon oxide composite anode material is I1, a diffraction peak intensity of Li2SiO3(111) with 2? being 26.8±0.3° in the XRD pattern is I2, and I1/I2<0.25. The material provided in the present invention has a specific phase composition ratio, thereby achieving the effect of high initial Coulombic efficiency and high specific capacity.

Abstract: A long-cycle and low-expansion silicon-carbon composite material with an internal pore structure includes a silicon source, a closed pore, a filling layer and a carbon coating layer. The closed pore is a large closed pore or composed of a plurality of small closed pores and the filling layer is a carbon filling layer. The invention provides a long-cycle and low-expansion silicon-carbon composite material with an internal pore structure which is reduced in volume expansion effect and improved in volume effect of cycle performance. The invention further provides a preparation method and application of a long-cycle and low-expansion silicon-carbon composite material with an internal pore structure. The process is simple. The volume expansion effect being reduced and the cycle performance being improved are of great significance to the application of silicon-based materials in lithium-ion batteries.

Abstract: A construction method of fast-setting polymer grouting for rapid control of slope erosion and landslide.

Abstract: The present invention relates to the field of anode materials for batteries, and in particular, relates to a self-filled coated silicon-based composite material. The self-filled coated silicon-based composite material is composed of a nano-silicon material, a filler material, and a surface modification material. The nano-silicon material has a particle size D50 being less than 200 nm; and the filler material is a carbon filler material filled among the nano-silicon material. The present invention provides the self-filled coated silicon-based composite material having the advantages of high initial efficiency, low expansion, long cycle, and the like. The present invention further provides a method for preparing the self-filled coated silicon-based composite material, and a use of the self-filled coated silicon-based composite material, which is simple and practicable in process and stable in product performance, and shows good application prospects.

Abstract: The present invention relates to the field of anode materials for batteries, and in particular, relates to a silicon-based composite material with a pomegranate-like structure. The silicon-based composite material with the pomegranate-like structure is composed of nano-silicon particles, exfoliated graphite, and a filler modification layer. The nano-silicon particles are dispersed in pores inside the exfoliated graphite. The filler modification layer is filled in the nano-silicon particles or filled between the nano-silicon particles and the exfoliated graphite. The present invention provides the silicon-based composite material with the pomegranate-like structure and a method for preparing the same, whereby a volumetric expansion effect can be reduced, and a cycle performance and a rate performance can be improved.