An e-charger includes a motor case that encases the motor and an outer housing that houses the motor case. The e-charger additionally includes a cooling system with passages cooperatively defined by the outer housing and the motor case. First and second longitudinal passages extend between the first and second ends of the motor, and a second longitudinal passage extends between the second and first ends of the motor. The end passage fluidly connects the first and second longitudinal passage. The cooling system is configured for directing flow of the coolant from the inlet, through the first longitudinal passage in a first longitudinal direction with respect to the axis, through the end passage, and back through the second longitudinal passage in a second longitudinal direction with respect to the axis.