I was looking for a way to charge my Bosch Powerpack 500 in my car. I was able to design/3D print the Bosch connector. I figured out how to put the battery in charge mode (). Once I figured that out, I created a Grin Cycle Satiator charger cable (). From my tests, I can charge at 6.5A. 7A is too much and shuts down the battery BMS. You can also hook up a solar charger like the Genasun GVB-8-41.7V-WP 8A solar boost MPPT charger ( https://amzn.to/3hncBKS ).