| abstract |
The invention discloses a method of preparing a material of a negative electrode of a lithium ion battery, effectively mitigating a size effect of silicon. The method comprises the following steps: firstly, preparing a modified graphene microchip; secondly, growing, on a surface of the graphene microchip, a silicon nanosphere, so as to obtain a graphene microchip-silicon nanosphere composite material; and depositing, using an atomic layer deposition technique, and on the surface of the graphene microchip-silicon nanosphere, a metal oxide layer; performing an electrostatic spinning and calcination treatment to obtain a carbon nanofiber composite material; performing an acid treatment on the carbon nanofiber composite material, removing a metal oxide layer to form a gap structure; and finally, forming a carbon coating layer covering outside the carbon nanofiber composite material. The method disclosed in the invention is utilized to prepare, using a simple preparation process, an accurate and controllable gap structure, effectively providing a space for volume expansion of the silicon in a charging and discharging process, and further protecting, using the carbon coating layer formed at the outermost layer, the silicon nanosphere, ensuring integrity of the electrode structure, and increasing stability of the electrode structure. |