These batteries are safe during normal use, but present a fire risk when over-charged, short-circuited, submerged in water or damaged. They are a main cause of waste fires, and can be extremely dangerous when thrown away with general rubbish, or mixed with other recyclable materials like card, metals and plastics.
Batteries can be damaged by dropping them or crashing e-bikes or e-scooters. Check your battery regularly for any signs of damage and if you suspect it is, it should be replaced and should not be used or charged. Where the battery is damaged, it can overheat and catch fire without warning. These fires quickly spread and are difficult to extinguish, causing widespread damage.