Positive composite material for lithium ion batteries and preparation method thereof

摘要

An anode composite material for lithium ion battery and a preparation method thereof. The composite material is a composite material formed by compounding at least one of SiCO, SiCNO, SiCN and SiBCN with LiaMbPO4, wherein 0.95≦a≦1.1, 0.95≦b≦1.1, and M is at least one of Fe, Co, Ni and Mn. The content of at least one of SiCO, SiCNO, SiCN and SiBCN in the anode composite material is in a range of 1-20 wt % of the total weight of the composite material. The composite material formed by compounding at least one of SiCO, SiCNO, SiCN and SiBCN with LiaMbPO4 is obtained by adding LiaMbPO4 into at least one organosilicon polymer of polysiloxane, polysilazane, and polyborosilazane, and then curing, crosslinking, and pyrolyzing. Compared with LiaMbPO4, the composite material has a notable improvement in electrochemistry performance and tap density.

主权项

1. A positive composite material for lithium ion batteries, characterized by being compounded with LiaMbPO4 by at least one of SiCO, SiCNO, SiCN and SiBCN, wherein 0.95≦a≦1.1; 0.95≦b≦1.1; M is at least one of Fe, Co, Ni and Mn; at least one of SiCO, SiCNO, SiCN and SiBCN accounts for 1-20 wt % of total weight of the composite material; the LiaMbPO4 accounts for 80-99 wt % of total weight of the composite material.