A one-for-all strategy of polyimide coating layer for resolving the comprehensive issues of phosphorus anode

Phosphorus is a promising anode with high capacity (2596 mAh g(-1) and 6075 similar to 6924 mAh cm(-3)), low lithium-ion diffusion barrier (0.08 eV), and appropriate lithiation potential (similar to 0.7 V vs Li+/Li). However, it faces the problems of huge volume expansion (similar to 300%), low electronic conductivity (10(-14)similar to 10(2) S cm(-1)), soluble intermediates (lithium polyphosphides, Li(x)Ps), degradation in air, and low thermal stabil-ity. In this work, phosphorus/carbon nanotube composites were coated with a polyimide layer, which plays the roles of a buffer layer to relieve the volume expansion of phosphorus, an obstruct layer to con -fine Li(x)Ps, an inert layer to prevent the degradation of phosphorus in air, a heat resistant layer to improve the thermal stability of the anode. The resulting composites (P/CNT@PI) display high capacity retention of 798.1 mAh g(-1) after 150 cycles at 1 A g(-1), achieving 17 times as much as the control sample (P/CNT).(c) 2022 Science Press and Dalian Institute of Chemical Physics, Chinese Academy of Sciences. Published by ELSEVIER B.V. and Science Press. All rights reserved.