Amino-Modified Porous Aromatic Frameworks for Enhanced Lithium-Ion Dissociation and Transport in Polymer Electrolytes

Abstract

Enhancing the ionic conductivity of solid polymer electrolytes and accelerating ion transport are pivotal challenges in achieving lithium-ion batteries with high energy density and excellent electrochemical performance. In this study, amino-modified porous aromatic frameworks (AMPAF) are prepared. The amino group in AMPAF stabilizes the anion through hydrogen bonding to reduce the dissociation energy barrier of Li⁺, enabling Li⁺ to be more easily dissociated from lithium salts. Additionally, the abundant pores of AMPAF promote the rapid transport of Li⁺. The prepared quasi-solid polymer electrolyte (AMPAF-QSPE) exhibited a high Li⁺ conductivity of 7.62 × 10⁻⁵ S cm⁻¹ and a Li⁺ transference number as high as 0.55, which proves the restriction of the amino group in AMPAF on the movement of anions and the ability to dissociate lithium salts. The discharge specific capacity of Li//AMPAF-QSPE//LiFePO₄ reached as high as 137 mAh g⁻¹ at 0.2 °C, and the capacity retention rate was stable at 85% after 200 cycles. This article presents an effective attempt to enhance the overall performance of polymer electrolytes using amino-modified PAF, offering an innovative perspective for the development of electrochemical energy storage technologies.