I ended up having someone else finish the wiring for me. To this day, I still don't know how that wiring the battery thing fully works. I have just have a general idea. I would still like to learn. If anyone could show me...preferably a video, that would be great! I plan on electrifying a cargo bike, and I want to do everything myself this time.

The bike is pretty good. Torque is substantial. However, the speed is pretty slow. It goes probably max 17 mph with a little pedaling.

Is there a way I can increase max speed? I was thinking about adding another identical Thundersky battery, making the battery pack go to 48v from its current 36v. However, I'm not sure what that does. Does adding a battery pack increase the capacity of the battery, or does it increase the amount of electricity it sends to the wheel so that it goes faster?

Also, I was pondering whether two wheel setup would increase speed. Would I be able to wire it to draw electricity from the current battery at the same time (basically supplying energy to both front/back wheels)? I was wondering, but then I remembered reading somewhere that the wheels might work against each other. Would it then be too inefficient?