Anyone have this system?

I really don't use a LOT of batteries but the idea of
throwing them away bothers me as we have no way to
recycle them here locally

I'm wondering if they would work ok in graphing
calculator?

Sorry to post here but didn't know where else to put
it.
Also, is there any diff between a cheap $13 Kodak NiMH
charger and more expensive $40 one?