RELAY DEVICE AND IN-VEHICLE SYSTEM

Provided is a relay device that is able to supply a charging current to at least two electrical storage units from a power generator. In a relay device, a first electrical storage unit-side conduction path is connected between a power generator-side conduction path and a first electrical storage unit, and a second electrical storage unit-side conduction path is connected between the power generator-side conduction path and a second electrical storage unit. A relay unit breaks electrical continuity between the first electrical storage unit and the second electrical storage unit when a first switch unit provided on the first electrical storage unit-side conduction path and a second switch unit provided on the second electrical storage unit-side conduction path are OFF. A control unit turns OFF the second switch unit when the first switch unit is ON, and turns OFF the first switch unit when the second switch unit is ON.