Gasoline is much safer than batteries.

Batteries have to carry a LOT of energy in a relatively fragile state, where the energy is split between a flimsy barrier. If the two sides ever link together - called a "short" - the battery can violently explode.

As we require bigger and bigger batteries charged with more and more KWH of electricity, the risk of a runaway chain reaction dumping all of that energy into an explosion or violent fire exponentially increases:

“Lithium ion battery fires are difficult to extinguish due to the thermal chemical process that produces great heat and continually reignites,” Hamden fire officials said.

Yes, because it's not just a chemical reaction where oxygen is reacting with something, like you see with gasoline and other chemical fuels. Battery fires are driven by the conversion of potential electrical energy into heat/fire, so spraying it with water does jack shit.