A shield for a fry pot includes a sheet of rectangular, pliable metal that may be formed in a cylindrical shaping to overlap edges of the shield to create an outer diameter substantially equal to an inner diameter of the fry pot. This can provide a vehicle power supply apparatus which is equipped with the power storage devices having different characteristics and offers improved performance. The valved outlet is reversible to enable the valve to be readily accessible when the modular section is in any orientation.