This project started when I recovered a big lithium battery from a broken/abandoned eScooter and solar panels from broken temporary street lights from the streets around me. The objective was to create a portable DC power station for charging laptops, USB devices, and portable refrigerator offgrid or as a backup during a grid blackout.
I purchased $105.94 in materials to make this happen, and invested lots of my time in learning, testing, and building the enclosure. Theoretically, I could reuse those materials in future projects if I decide to dismantle this. Without counting labor, the price comes down to about $0.11 per Wh (watt hour), which is a lot better than $1.10 per Wh in commercial options.
Portable power station components, using scrap plywood and clear acrylic for the housing:
Testing the panels wiring in series: