I have been looking into batteries recently for an application where I need high capacity and roughly a 10 year lifespan. Oh and they have to work at extreme temperatures (-60 C to 50 C would be sweet), and be priced reasonably. Lithium SOCl2 is a cool chemistry which fits the bill, but is hazmat. I think Lithium Manganese ones are a decent compromise. Does anyone have any better ideas?
pretty much the gold standard in extremely long life batteries, non rechargable lithium, but they're not cheap:
I bought 16 total Low Self-Sidcharge NiMh AAA/AA from amazon back to 2009.
That was the last time I buy batteries in that spec because they still work today.
I'm only aware of one real use for D batteries...
The local transit-cops seem to like them for adding weight to their billy-clubs. A secondary function seems to be to make one end of the clubs light up, but a pocket LED flashlight is usually way brighter.