Aldi Ferrex 20V/40V Power Tool Batteries Dismantled
JLCPCB Prototype for $2(Any Color): https://jlcpcb.com
Both the 20V and the 20V/40V battery dismantled to check the cell specs:
20V battery has LG HD2 cells - 2Ah capacity, 25A max continuous discharge, 4A fast charge.
20V/40V battery has LG HE4 cells - 2.5Ah capacity, 20A continuous discharge, 4A fast charge.