3results about How to "Relieve swelling" patented technology

The application provides a silicon-carbon negative electrode material and a preparation method and a lithium ion battery thereof, the silicon-carbon negative electrode material is a grape-like secondary particle, the secondary particle is composed of primary particles, carbon nanotubes and graphite, the surface of the primary particle is connected with the graphite through the carbon nanotubes; the primary particle is a double-coated silicon-based material, the inner core of the primary particle is a silicon-based material, the inner coating layer is an oxide layer, and the outer coating layer is a carbon coating layer. The application effectively enhances the conductivity of the silicon-carbon negative electrode material by designing the grape-like silicon-carbon negative electrode material, solves the problems of particle separation and poor conductivity in the expansion process, and the material has a high degree of disorder, which is beneficial to improving the fast-charging performance of the material; in addition, the double-coated silicon-based material surface can improve the initial efficiency while reducing the residual of the surface alkali, and can effectively alleviate the expansion problem of the silicon-based material, reduce the erosion of the electrolyte to the surface of the silicon-based material, and further enhance the cycle performance of the material.

A silicon-carbon anode material with a curved graphite layer structure and its preparation method are disclosed, belonging to the field of battery anode materials. The specific solution is as follows: A silicon-carbon anode material with a curved graphite layer structure comprises a silicon phase and a carbon phase. The carbon phase is a partially graphitized carbon matrix, which includes multiple multilayer curved graphite layer units. Micropores are formed between these multiple multilayer curved graphite layer units, and an interconnected pore network is formed between the arched cavities of the multilayer curved graphite layers and the micropores. The silicon phase is distributed on the surface of the multilayer curved graphite layer units, inside the arched cavities, and within the micropores. In this invention, the arched cavities formed by the multiple multilayer curved graphite layer units are interconnected with the micropores, providing effective pores to alleviate silicon expansion while also providing an effective pathway for subsequent ion transport.

This invention discloses a negative electrode sheet and a lithium-ion battery. The negative electrode sheet includes at least two sets of active units coated sequentially from one side of a negative electrode current collector. Each set of active units includes a graphite negative electrode layer and a hard carbon negative electrode layer coated sequentially from the inside out. The graphite negative electrode layer has multiple pores spaced apart on the side adjacent to the hard carbon negative electrode layer, and hard carbon negative electrode material for forming the hard carbon negative electrode layer is embedded within these pores. The pore capacity between each set of active units increases sequentially from the inside out. This invention, by optimizing the negative electrode sheet structure, can significantly improve the low-temperature charge-discharge cycle performance of the battery. This multi-layer negative electrode sheet has the advantages of high charging efficiency and strong low-temperature charge-discharge capability, which can significantly improve the high-rate charge-discharge performance of lithium-ion batteries and extend the electrode life under high-rate charge-discharge conditions.