For ~$20, you can turn your Ryobi 18V battery into a power engine for your IoT projects or a mega battery charger that would last you many days out in the camp or where ever you choose to be without AC power.
Here is the link to the 3D-printed power clip: ~$5
https://www.thingiverse.com/thing:1194867
12V Car Lighter Socket/Plug: ~$6
https://www.amazon.com/gp/product/B015H6945S/
24V-tolerant USB Car charger: ~$9
https://www.amazon.com/gp/product/B014ZZLLB2/
