Overview of Hybrid Electric Vehicle Safety and the Potential for Hydrogen Ignition by Static Electricity

Hybrid Electric vehicles (HEVs) and Fuel Cell vehicles (FCVs) are showing promise of success as a commercial product as they are being developed by the industry. It is only prudent to closely consider safety issues for both post-crash and failure (non-crash) scenarios.

A review of most relevant technologies being considered for HEVs was performed to identify potential hazard conditions and interactions between systems and sub-systems within these vehicles. Energy storage, propulsion systems and fuel storage were examined for different configurations of such vehicles.

It is anticipated that plastics, composites and other nonconductive materials will be used more widely in future cars. This can result in an increased propensity to generate substantial static charge levels. Furthermore, the presence of high-voltage and high-current lines, batteries, electric motors and other components not present in conventional vehicles with alternative fuels or hydrogen justifies this examination. Areas of potential hazards in post-crash as well as nominal operating conditions are discussed. Special emphasis has been placed on investigating ignition of hydrogen-air mixtures by electro-static discharges.