Abstract
The practical and widespread use of fuel cell vehicles (FCVs) is eagerly awaited, because such vehicles impose less environmental load, increase energy security, and strengthen Japan´s industrial competitiveness. The Ministry of Land, Infrastructure and Transport in Japan has subsequently undertaken studies on possible safety and environmental regulations for FCVs fueled by compressed hydrogen, which are currently the mainstream and closest to market use, in the "Project to Promote Practical Use of FCVs". Based on the results of this research, the Ministry issued the partially revised Safety Regulations for Road Vehicles and established technical standards in order to introduce the type approval system for mass production of FCVs in March 2005 (1). It is the first event in the world.
This paper covers the technical background of these Japanese technical standards. In the "Project to Promote Practical Use of FCVs", National Traffic Safety and Environment Laboratory acted as a key research body for gathering data, carrying out experiments and analyzing them with close cooperation between industry and government. The results of the investigation and the technical outline of standards are summarized in this paper.
I. Hydrogen safety
The safety concept for vehicles fueled by compressed hydrogen is as follows.
- To prevent gas leaks; To make gas dissipate rapidly if it leaks; To detect leaks and shut off hydrogen gas in case of a leak; and
- To safely discharge gas that contains hydrogen.
II. Safety against fuel (hydrogen gas) leak upon crashes
It is crucial to secure safety in the event of a crash-triggered fuel leak for vehicles powered by compressed hydrogen, equivalent to the level of safety provided for vehicles powered by gasoline.
III. High-voltage safety (Protection from electric shocks) As fuel cell stacks generate driving-power electricity at high voltage, passengers in FCVs need to be protected against electric shocks. Technical requirements are to be based on ECE
Regulation No. 100 for electric vehicles, adding factors unique to FCVs.
Keywords:Fuel Cell, Automobile Standards, Hydrogen Safety, Electric Safety, Crash worthiness