NOVELTY - Electromagnetic battery relay (1) has hub (35) formed in the end plate (34) and accommodates the end of press spring (46). A spring base (43) is separately provided with the plunger shaft (41) and allows mounting of the end of press spring at a position corresponding to the hub of plunger shaft. End plate is positioned at the end of coil bobbin (20).    USE - Electromagnetic battery relay for controlling electric power supply to electrical component mounted in e.g. motor vehicle.    ADVANTAGE - Ensures sealing performance between spigot and first enlarged diameter portion since O-ring is interposed in a state crushed between the spigot of terminal cover and first enlarged diameter portion of yoke. Prevents penetration of dust from the lead wire penetration hole into the battery relay due to grommet. Improves reliability of on operation of the battery relay and suppresses heat generation caused by contact resistance since contact pressure of the movable contacts with respect to stationary contact is increased and contact resistance between stationary contact and movable contacts is made small with the restoring force of press spring. Suppresses impact noise since press spring relieves the impact at the time of movable contacts colliding with the stationary contact. Narrowing the diameter of plunger shaft that supports the plunger is ensures while obtaining weight reduction by setting the size of plunger to necessary minimum size. Obtains axial shortening of the battery relay while increasing the length of press spring with simple structure at low cost since placement space of the press spring is set long to the end plate at axial direction. Ensures favorable opening/closing of battery relay since shakiness of movable piece is suppressed. Conversion cost of the plunger shaft is held down and manufacturing cost of the battery relay is reduced since end of press spring is held without expanding the large diameter portion of plunger shaft. Maintains space factor of the conventional coil, improves space factor of the coil and provides highly efficient battery relay by increasing the number of turns of a portion that forms the diameter reducing portion in the winding drum unit of coil bobbin. Highly efficient battery relay is provided without enlarging the outer diameter of coil bobbin or yoke since thickness of the whole end plate is equalized and magnetic path through which the magnetic flux flows into the surrounding wall of hub is formed.    DESCRIPTION OF DRAWING(S) - The drawing shows a sectional view of the electromagnetic battery relay.    Battery relay (1)    Coil bobbin (20)    End plate (34)    Hub (35)    Plunger shaft (41)    Spring base (43)    Press spring (46)