Be wary of, or careful when using, these dumb adapters. Lithium batteries require protection electronics, in particular ones to shut off the tool when the battery reaches too high a temperature or the cells reach too low a voltage. Most manufacturers put the electronics in the tool, using the connector's other conductors to sense the battery's condition. Since these cheap adapters don't also adapt the sensing electronics and conductors, the electronic safety is substantially or completely disabled. If the battery's user doesn't take as much care as the tool's electronics would have, there is a great increase in the probability of premature, and possibly incindiary, battery failure.

Yeah, they've addressed phone and car chargers, that'd be a logical next step.

This problem isn't on the political radar yet. Give it time.

Nthing this. ProjectFarm is an impressive, objective, numbers based review of all sorts of tools and lubricants. The guy looks like your average farmer, but he covers pretty much every real world use case and is always impressively thorough, with the knowledge of someone who has actually used tools/products like that in the field. He also does some amusing things like lubricating a lawn mower with bananas.

Just don't short them accidentally. And check the voltage and charge/discharge power. And maybe check the thermal probe still works.