D−A polymers exhibit excellent intramolecular charge transfer (ICT) properties due to the differences in energy levels. However, bulky dihedral angles between D and A units with conjugated structures have a negative impact on the process of ICT, which inhibits efficient electron transport between adjacent conjugated units. To solve this problem, the noncovalent conformational locks were constructed by the introduction of π-bridges. Intriguingly, thiophene π-bridges containing sulfur elements can form S�H noncovalent conformational locks, which not only extend the conjugated structure to overcome the steric hindrance but also enhance the efficiency of charge transport. Therefore, PFPy-TT and PFPy-TTBT with conformational locks exhibited superior shortcircuit density (J SC ) compared to PFPy-BT without conformational locks. Meanwhile, PFPy-TTBT with a benzothiazole moiety exhibits stronger ICT properties and better electron extraction efficiency compared to PFPy-TT without a D−A structure. The enhanced ICT properties enable PFPy-TTBT to have better intramolecular and intermolecular electron transport performance, realizing a power conversion efficiency (PCE) of 16.15%. By constructing noncovalent conformational locks using π-bridges in cathode interfacial layers (CILs), the problem of inferior coplanarity is resolved, and favorable molecular alignment is promoted, while also demonstrating exceptional storage, light, heat, and air stability. A device with PFPy-TTBT maintains over 80% of its initial PCE value when stored in nitrogen condition for 120 h. These advances hold promise for improving charge transfer and film quality in organic solar cells.