Then I have no idea what was your previous post about. Everyone here talks about groups of cruisers, not soloing a BS.
A cruiser is not meant to be able to solo a battleship. It could happen with great skill and luck, even against a decent BS, but it would be extremely rare. It would take VERY long and any mistake of the cruiser would be deadly. BS missiles could prevent it entirely though. I'm not sure about them in this scenario.