Anecdotally I've had this happen with both of my old iPhone 3G's and an iPhone 4. Fortunately, I managed to rummage through the junk drawer in my home to find

Anecdotally I've had this happen with both of my old iPhone 3G's and an iPhone 4. Fortunately, I managed to rummage through the junk drawer in my home to find these before anything bad happened. Tbh, I'm surprised keeping Li-Ion devices in fireproof boxes isn't more common - my brother does this with all of his drone equipment, ironic we don't do this with other consumer electronics.