I wonder if the DEWALT 18V to 20V Battery Adapter Kit has a BMS in the 20V 2.0AH batteries they include (DCB203 20v MAX XR). They do mention "Do not use with premium batteries (DCB200, DCB204, DCB204BT, DCB205) in 18V Compact drills DC970, DC759 (use DCB201, DCB203, DCB203BT)."