▎ 摘　　要

NOVELTY - A secondary battery comprises additive comprising nitrogen-containing group-modified polyethylene glycol. USE - Secondary battery. ADVANTAGE - The secondary battery uses additive to effectively improve the composition of the anode interface film and reduce the increase of internal resistance during the anode cycle and improve the cycle life. The additive can form solid interface film on positive electrode with excellent lithium conductivity and stability, and improve the conduction of electrons and lithium ions inside the positive electrode sheet of the secondary battery due to increase in content of polymer components in the solid-state interface film, which improve the kinetics of lithium ions inside the positive electrode sheet, and improve the cycle performance of battery.