I know a photographic guy that is real big on Eneloop AA Batteries from Sanyo. They are rechargeable, by regular recharger like a LaCrosse BC-900 or by your solar item you listed, but the big thing about these Sanyos is that they retain power when not being drawn down.
They hold 20% less charge initially but they will hold over 85% of that charge for a year or better. They will also hold thier power after partial usage — something regular or rechargeable batteries of other brands never do.
LOL
I just so happen to have 3 packs of Eneloops and saw they were back at Costco the other day.
Going shopping tomorrow and picking two more packs.
Can’t have too much of anything.
The recharge I use a Duracell thingy and seems to work real well.
I bought these because of their claim and I wrote the date I purchased them to remind what their charge will be when I use them.
I do the same on my other rechargeables. I charge them then put them in a plastic container, place a stamp on the container and write the date those went in the container.