A stator assembly for a hybrid module includes a stator carrier, a stator segment, and a water jacket. The stator carrier has an inner cylindrical surface and the stator segment is installed in the inner cylindrical surface. The water jacket is fixed to the stator carrier to enclose a sealed chamber therebetween. The water jacket may be fixed to the stator carrier by a pair of circumferential welds at opposite ends of the sealed chamber. The stator assembly may include a fluid port fixed to the water jacket and arranged to guide a fluid into or out of the sealed chamber to cool the stator assembly.