The ones used in these “single use” devices are almost universally just standard Li-Ion.

In vapes it’s almost certain, as other battery types just don’t work very well for this application. Also, many of these come rechargeable now (but not refillable).

In “emergency chargers”, you could in theory use something different but usually it’s lithium too: https://www.youtube.com/watch?v=6lflk6iY56w

Depends.

https://www.youtube.com/watch?v=N65DpT2nqEI

Though the UK did just recently ban some of the worst offenders https://www.gov.uk/government/news/single-use-vapes-banned-f...