Enhanced Regional Electric Potential Difference of Graphdiyne Through Asymmetric Substitution Strategy Boosts Li+ Migration in Composite Polymer Solid-State Electrolyte

• Methoxy-substituted graphdiyne (OGDY) is synthesized via an asymmetric substitution strategy, featuring a periodic alternation of electron-rich regions and electron-deficient regions, which significantly enhances the heterogeneity of charge distribution in OGDY. • An enhanced regional electric potential difference design concept is proposed to address the low ionic conductivity of polymer solid-state electrolytes. The OGDY/poly(ethylene oxide) composite polymer solid-state electrolyte achieves an ionic conductivity of 1.1×10−3 S cm−1 and a high lithium-ion transference number of 0.71. • The accelerated Li+ migration promotes the formation of uniform and dense SEI layers and inhibits the growth of lithium dendrites, enhancing battery performance. • Li||Li symmetric cell and Li||LiFePO4 full cell and pouch cell assembled with OGDY/PEO exhibit good performance, highlighting the effectiveness of the EREPD design strategy for improving CPSEs performance.