I am planning to use a 18650 battery and a casing like below to run a raspberry pi zero W outside on my watch, but I hear bad stories about lithium ion batteries, like 18650, exploding on a regular use.
I see 18650 batteries with protection circuit installed, but people talk about bad/fake circuits, and I don't know what to rely on.
I don't have enough knowledge to be confident on this kind of power supplies. I would like to ask people with knowledges what I should look for more safe battery power supplies.
For an instance, if I get a case like below which seems to have some protection circuit in it, does it mean I don't need a 18650 with protection circuit?
Or, if the circuit in this battery case isn't really for protection, how can one tell what is protection circuit, and how safe the circuit it is?