After commercializing MIRAI in 2014, Toyota is focusing more on further cost reduction, and improvement in performance, durability and reliability, which are still challenging for wide-spreading commercialization enabling PEFC technology for next generation FCVs. To enhance PEFC performance directly impacts towards cost reduction due to reduce an amount of PEFC stack materials. Significant R&D efforts and advancements have been made towards filling the gap to the target on PEFC performance. For example, catalyst research aims not only to improve ORR activity itself but also to enhance mass transport performance in the high current region. The mass transport performance depends greatly on its microscopic structure of electrodes. Electrodes are fablicated from catalyst ink, which is a multi-component system, consisting of catalyst carbon, ionomer, and solvent. We employed several visualization techniques to unveil the structure of catalyst ink and electrodes respectively and discuss the relationship between the structure of catalyst ink and electrodes, and its performance. The technical prospects and R&D approaches for the remaining technical challenges on durability and reliability for the next generation FCVs will be also discussed.