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As Chris mentioned, there are pitfalls. Unfortunately you will need to do some research or experimentation to work out which chargers will work with a solar power source.

In my experience, there are precious few AA chargers that will work correctly with a low-power or fluctuating source, even if the panel itself resets the port after clouds. The GoalZero Guide10+ is very good when paired with the Nomad 7 panel in any kind of lighting, but it is very expensive and needs to charge 4AA or 4AAA at a time. I also use mine as a buffer pack to run my Sanyo Eneloop USB charger for doing 1 or 2 AA or AAA.

Some USB power banks can act as a buffer pack, but many will not. I can’t recall if the correct term is “passthrough” or “bypass” but many USB packs will either not output at all whilst charging, or will not hold a regulated 5V. My otherwise excellent Xiaomi banks are examples of ones that won’t work properly as a buffer.

One of the best and cheapest buffer packs I’ve used has been a simple Miller ML-102 loaded with an 18650 or 266650 Li-Ion cell. It is easier to find small, portable, solar compatible USB chargers for Li-Ion than for NiMH. The Xtar MC1 (and the Miller above) both keep trickling current into your cell even with very low output from the panel.

If you want to reliably charge large numbers of devices or cells, then a 12V setup like Chris has posted is the sensible way to go. It may not suit backpackers or canoeists, but as a static installation or for vehicle use you get much more capacity and reliability. Splash out on an MPPT charge controller if you want the best from your panels in less than ideal sunlight.
Consider a LiFePO4 12V pack rather than Lead Acid if you want long life and can afford it.

Lots of useful threads in BLF.