Here's a thought:
There were 6,570,000 automobile accidents in 2002 ( only statistic I could find easily ) Suppose half the cars were Hybrids, that makes 3,285,000 involving batteries. I know the batteries are supposed not to leak in a "normal" collision ( anyone ever have one of these ? ) Let's assume that 10% generate enough impact to dump the batteries, that's 328,500 clean-ups on aisle 5 for Hazmat to deal with.
Lovely,
P.G.