Post 58 has a yt video link to TTC, where there are modded Milwaukee packs.
3s2p of P30b should be a beast, if the specific tool can take advantage of it.
My old 10s1p AA 12v nimh electrolux vaccuum cleaner was an absolute beast on an 18v Ridgid pack, but woukld not fire up unless it was under 19.4v, and it fairly recently burnt out, the motor still hot enough to burn my fingers after a non rushed disassembly.