▎ 摘　　要

NOVELTY - Polyimide binder is prepared from imidazole group-containing diamine, sulfonated diamine, and ketone group-containing dianhydride through copolymerization and imidization. USE - Polyimide binder for silicon-based negative electrode sheet of a lithium battery (claimed). ADVANTAGE - The polyimide binder has excellent adhesion to the current collector and the silicon-based active material, better inhibits the volume expansion of the silicon-based active material during the charge and discharge process, and is beneficial to improve the cycle stability of the battery. The adhesive also has good performance in terms of flexibility and heat resistance. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are included for: 1. a silicon-based negative electrode sheet, which comprises polyimide binder; and 2. preparation method of silicon-based negative electrode sheet, which involves adding a polyimide binder, a silicon-containing active material and a conductive auxiliary agent into a solvent, and uniformly stirring to obtain negative electrode slurry; then coating the negative electrode slurry on a current collector, drying, and performing punch forming to obtain a silicon-based negative electrode plate, where the weight ratio of the polyimide binder, silicon-containing active material and conductive auxiliary agent is 15-25:60-90:15-25.