well kinda/sorta on topic, so here goes….
since i am cheap, i have found that the outdoor solar lights
are “good enough” to recharge the AAA size. i buy 3 or 4
at the Dollar Store ($1.25 now) when i find the AAA’s
inside. they are removable, so i switch out batteries.
i have never found 18650’s or AA rechargeable
solar lights within my budget limits.