Thanks. Would you mind telling me what solar panel you use with the battery pack?
I have a rather old goalzero foldable charger but it's on its last legs (panel covering is yellowing and charging speed has slowed to a trickle) so I'm currently vetting new solutions.
I also have one of these:
https://www.amazon.com/gp/product/B076PR4TBZ/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1 which I used for the first time last year and it has a MC4 hookup. So I'm considering buying a new 40-50W panel (currently debating rigid vs foldable) to hook to this and THEN charge the battery banks off of that. This will result in some inefficiency but I think this will be easier to deploy in a sunny spot because where we camp gets minimal direct sunlight.
However since we're in Town Park, I may skip the whole solar deal and just charge up periodically at Herzog or the bath house.