I did a review on 5 or 6 of solar chargers, search for ‘Foldable Solar Charger’
http://budgetlightforum.com/forum/batteries/usb-power
Out of the ones I reviewed I liked the Allpowers 20W
I have several more I haven’t reviewed yet. I really like the new 4panel ravpower on amazon, but I haven’t tested it thoroughly yet:
https://www.amazon.com/Charger-RAVPower-Waterproof-Foldable-Smartphones/dp/B06XBGSS2R/
Something to keep in mind… you probably want to use a power bank with the solar charger for several reasons (which I wont get into now)… and you should test the two thoroughly before you rely on them to work.