Dont worry, I'm here!
As far as I know there is not one available - Scurion themselves certainly do not produce one. There is very little space inside the battery box at present, so I think you'd struggle to make an adapter that would fit inside the case.
Bare 18650s certainly would be a massive advantage and IMO is one of the big selling features of the Phaethon light. I've thought about mentioning this to Rolf in the past, as it would remove one of the weakest points in the Scurion system (the battery connector), but it would involve a massive redesign of the battery box, so might not be commercially viable. If anybody does manage to design one that works I'd certainly be interested in taking a look!
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