Bad Friedrichshall is at the confluence ( place where two rivers join ) of the Neckar and the Kocher , 10 k north of Heilbronn . Bad Friedrichshall is a town in the district of Heilbronn in Baden-W Ã 1\/4 rttemberg in southern Germany . It is situated at the confluence of the Jagst and the Kocher into the Neckar , 10 km north of Heilbronn .