The paper reports the achievement of high-performance ( efficiencies up to 10.8%, fill factors up to 77%) thick-film polymer solar cells (PSCs) for multiple polymer:fullerene combinations by controlling the temperature-dependent aggregation behavior of donor polymers. This approach forms a near-ideal polymer:fullerene morphology with highly crystalline, sufficiently pure, and reasonably small polymer domains, which is insensitive to the choice of fullerenes. The study identifies three high-efficiency (>10%) donor polymers and demonstrates their potential for further synthetic advances and material matching, potentially leading to significantly improved PSC performance and increased design flexibility. The key structural feature of the donor polymers is the second-position branched alkyl chains (2OD) on quaterthiophene, which enables controllable aggregation during the film-forming process. This approach offers a new route to achieve high-performance thick-film PSCs and will accelerate the materials and process development in the field.The paper reports the achievement of high-performance ( efficiencies up to 10.8%, fill factors up to 77%) thick-film polymer solar cells (PSCs) for multiple polymer:fullerene combinations by controlling the temperature-dependent aggregation behavior of donor polymers. This approach forms a near-ideal polymer:fullerene morphology with highly crystalline, sufficiently pure, and reasonably small polymer domains, which is insensitive to the choice of fullerenes. The study identifies three high-efficiency (>10%) donor polymers and demonstrates their potential for further synthetic advances and material matching, potentially leading to significantly improved PSC performance and increased design flexibility. The key structural feature of the donor polymers is the second-position branched alkyl chains (2OD) on quaterthiophene, which enables controllable aggregation during the film-forming process. This approach offers a new route to achieve high-performance thick-film PSCs and will accelerate the materials and process development in the field.