1results about How to "Reduce irreversible capacity" patented technology

This invention relates to the field of lithium-ion batteries, and more particularly to a negative electrode material for lithium-ion batteries and its preparation method. The invention provides a powdered carbon material with a core-shell structure. The core of this microporous carbon material is coated with a carbon material shell. The core has a particle size of 3-8 μm and contains a large number of micropores with a pore size of 0.001-0.5 nm, accounting for 60-90% of the total pore volume of the core. The remainder consists of micropores with a pore size greater than 0.5 nm-50 nm. The interlayer spacing of the 002 crystal planes constituting the core is 0.39-0.41 nm. The shell has a thickness of 10-1000 nm, preferably 10-200 nm, with a pore size of 0.001-10 nm. The interlayer spacing of the 002 crystal planes constituting the shell is 0.34-0.36 nm. The negative electrode material provided by this invention has a hard carbon structure with a large interlayer spacing, which facilitates the diffusion of lithium ions within it, enabling rapid charging and discharging within the electrode and achieving high-rate performance of the negative electrode material.