There are tons of rechargeable standardized batteries I have cr2032 coin batteries, the 18650 (iirc). Regarding adapters, I have been replacing them with USB-C

There are tons of rechargeable standardized batteries I have cr2032 coin batteries, the 18650 (iirc). Regarding adapters, I have been replacing them with USB-C-to-barrel connectors and even got three devices off a single GAN charger. I have been trying to find the pitfalls of this but it’s awesome in theory!