How are Li-ion batteries a safety hazard?

Question

Quizplus · Accepted Answer

Li-ion batteries can explode or catch on fire if subjected to high temperatures, making them a safety hazard. While they do contain chemicals, they are often contained within the battery and not easily accessible, so they are not a major skin hazard. There is also no evidence to suggest that they are toxic to animals. While they do contain particles, these are typically not hazardous unless the battery is damaged and the particles are released into the air.

How Are Li-Ion Batteries a Safety Hazard