Mikio Kizaki

Development of Fuel Cell Hybrid Vehicles in TOYOTA

A fuel cell uses hydrogen and oxygen to generate electricity and does not emit CO2, NOtimes or PM. It is a clean and highly efficient energy conversion device and it raises the expectations for the commercialization of a vehicle that uses the fuel cell as a power source. Toyota Motor Corporation (TMC) started development of fuel cell hybrid vehicles in 1992. TMC developed the fuel cell stack and major components of the fuel cell hybrid system completely in house, and began limited marketing of the TOYOTA FCHV (Fuel Cell Hybrid Vehicle) in December 2002. In June 2005, the improved FCHV became the first fuel cell vehicle in Japan to acquire vehicle type certification. TMC has been working toward the solutions of many technical challenges to realize widespread use of fuel cell vehicles, including improvement of driving range and freeze start capability as well as enhancement of their marketability.

Recent Advances in TOYOTA FCHV-adv Fuel Cell System

Toward the mass introduction start in 2015, Toyota continues efforts to overcome the remaining technical challenges for the commercialization of the TOYOTA FCHV. The cold start capability is one of the main issues among such challenges. An excess amount of water in fuel cells hinders the cold start, because the water turns into ice. On the other hand, when there is a lack of water in fuel cells, the initial FC output decreases. To resolve the issue of the cold start capability, the AC impedance measurement was employed for estimating the water content in the FC stack. Based on this, the water management system was developed, and it became possible to start up the FCHV at temperatures down to -30{degree sign}C.