Abstract: An electromagnetic relay includes a sealed housing, a fixed contact, a movable element having a movable contact, a shaft, a movable core, a fixed core, a return spring, an electromagnetic coil and a sleeve. The shaft is slidably inserted in a through-hole formed in the fixed core. The sleeve has a support part supporting the movable core so as to define a position of the movable core relative to the fixed core when no magnetic attraction acts therebetween. At a front end of the sleeve, there is formed a position adjustment part for adjusting a positional relationship between the fixed core and the support part during the direct or indirect fixing of the sleeve to the fixed core.

Abstract: A relay control device controls an operation of a relay circuit, which is disposed between a battery and an electric load, and the relay circuit is sealed in a case of a battery pack. The relay circuit includes: a first main relay disposed in a first conduction path which is connected to a first terminal of the battery; a second main relay disposed in a second conduction path which is connected to a second terminal of the battery; and a pre-charge relay connected to the second conduction path in parallel with the second main relay. The relay control device turns on the pre-charge relay, the first main relay, and the second main relay in order, and then turns off the pre-charge relay, the first main relay, and the second main relay in order.