Negative electrode active material modified by zwitterionic polymer, and preparation method and applications thereof

The present invention provides a negative electrode active material modified by zwitterionic polymer, which comprises a negative electrode active powder and a nano-scaled layer of zwitterionic polymer coated on the negative electrode active powder. Besides, the present invention also relates to the preparation method and applications of the above-mentioned negative electrode active material. The replacement of the negative electrode active material used in conventional cells with the negative electrode active material modified by zwitterionic polymer of the present invention benefits ion insertion and extraction, reduces irreversible reaction and prolongs cycle life of cells, thereby enhancing overall effectiveness of cells.