Yes, this is really hard to do without lots of pictures and measurements.
Some of those Hailongs use round pins too. Luna has a pack called the Shark, and the Whale. Then you have the Dolphin packs. a design which is at least 8 years old.
You can have Silverfish packs. of different heights. with either 4 or 2 pins, plus they often flip the pin polarity. I recall one poster had two of these. One worked, and one did not. Turned out they did flip polarity, but the battery was well protected. When it was inserted and turned on, the BMS saw the dead short and simply powered off. No drama. No sparks.
Last edited by Doc_Wui; 06-09-21 at 01:16 PM.