The nice thing about that is you could use a low power adapter and have it charging constantly (<20W), and should still be fine for most use cases.
They are saying 80W, so 40W+ from each 18650, or about 11A each... ah hope those are good quality cells.
Though I actually hope that spec is BS, driving a C210 at 80W is not necessary at all. 40-50W is fine.
JBCs portable unit is specified at 24W:
https://www.jbctools.com/biron-500-tool-precision-handle-product-2512.htmledit: better be an earth port on this I don't see one in the photos
edit2:
T380 T210 handle pinout
1,6 - green
2 - red
5 - blue