Abstract
For several years now, there has been a strong drive in the automotive industry to displace the NiMH batteries in Hybrid Electric Vehicles (HEV) with lighter, more durable, more powerful and potentially less expensive Li-Ion batteries. These efforts have been hampered mostly by the concerns over the safety of the Li-Ion batteries. Such concerns have been overblown by merely focusing on abusive testing without paying equal attention to assessing the risk posed by such batteries in the event of a mishap. History shows that the automotive industry has been very successful in managing the risk posed by gasoline, a highly combustible fluid with an energy density 100 times more than the most energy-dense of advance batteries. This paper discusses a methodology developed for the risk assessment of advance batteries. Although the focus here is on the batteries used in hybrid, electric, or plug-in vehicles, the methodology itself, called Hazard Modes & Risk Mitigation Analysis (HMRMA), is quite general and can be used in other applications for batteries as well as for other components & parts that maybe considered hazardous. In addition, the methodology quantifies the risk associated with each hazard and becomes a valuable design tool to develop the most effective way of reducing the risk.