I thought Prius had completely shifted to lithium, but they have not. The Prius 2 is lithium.
There are about 300 million vehicles in the US. According to your site, more than 4 million are hybrids. According to the NFPA, there about 170,000 vehicle fires each year, so if the rates were the same, there should be more than 2,000 hybrid fires per year. According to Elon Musk, who is not unbiased, the actual rate of electric vehicle fires is 20% of traditional.
And, as has been pointed out on this thread, which has more stored energy, a tank of fuel, or a battery pack?