@duc Most people will have some sort of a phone, so that's one, and then people are gonna have various other electronics on them, with varied probabilities, and then some people are not going to have a phone... but I imagine it comes out to >1 in the balance.
@Dee smart watches have become somewhat common, laptops are a thing, and mobile phones are pretty common even in developing countries i believe? which is why it probably is more than 1
@duc@Dee folding phones are starting to come with two batteries to fit into the gimmicky shape. Plus I imagine many diabetics have at least an extra battery for a blood sugar monitor or insulin pump, though they might not be lithium.
Does every set of wireless ear buds count as 3 batteries?