(Invited) Fuel Cell Stack Technology of Toyota

Abstract

Toyota Motor Corporation launched the Prius, the world’s first mass-production hybrid vehicle (HV), in 1997. The global popularization of the Prius and other HVs has helped to counteract the negative effects of vehicles on the environment. As emerging markets continue to develop economically and the world’s population grows, vehicles are likely to have an even greater impact on the environment. Therefore, if vehicles are to remain of benefit and interest to society in the next one-hundred years, it will be even more important to find answers to issues related to energy and the ideal form of mobility in the future. Through the development of hybrid, plug-in hybrid, and battery electric vehicles, Toyota is already acting proactively to encourage the use of electricity. In addition, Toyota has also taken the step of developing fuel cell vehicles (FCVs) to help promote the use of hydrogen for contribution to environment.A fuel cell (FC) generates power by electrochemical reactions through an electrocatalyst using hydrogen and oxygen in the air. Since these reactions generate only water as a by-product, FCs are regarded as an extremely clean and efficient means of generating power, with the potential to help resolve energy and environmental issues in the future. Greatly enhancing the performance and reducing the size and cost of the FC stack is an important part of measures aimed to facilitate the widespread adoption of FCVs.A FC stack consists of a wide range of materials, including various types of mechanical elements and electronic parts. In particular, cells inside the FC use many materials that are not found in conventional vehicle parts. In contrast to the research phase, which prioritized efforts to enhance the functional performance of the FC stack, the new mass-production MIRAI FCV was developed as a normal industrial product with an emphasis on both performance and the applicability of manufacturing methods. This article describes several examples of manufacturing methods adopted to ensure high quality and productivity while reducing cost.