Solar charging the MarkSetBot battery is simple.
A 12V panel(s) and a 12V controller is needed. The controller must support LiFePo4. Two popular options are to buy a mobile kit or to buy a permanently mounted kit.
Here are the parts needed to mount on the Bot:
https://www.amazon.com/gp/product/B07BMQRNXZ
https://www.amazon.com/gp/product/B07YXZ68F5
Here are two foldable mobile options:
https://www.amazon.com/gp/product/B073W1S43K
https://www.amazon.com/gp/product/B07RFQVB9M
Here is a starting point for a permanently mounted solution:
https://www.amazon.com/gp/product/B07YXZMKD2
https://www.amazon.com/gp/product/B07MZKY9H5
If you prefer to skip the hassle of building your own solar charging system, MarkSetBot sells on-water and on-shore solar set-ups.