[_Microft]

Atomic batteries are a thing; I was wondering how they could be made chargeable.

[addaon]

One thing that comes to mind is Hafnium 178m2, but (for understandable reasons) there's basically zero public information about the feasibility of charging and induced discharging of any nuclear isomer, let alone one so energy dense.

[_Microft]

Cool, thanks for pointing that out! This is basically what I was thinking about in my reply to user dongobongo.