To operate the battery in a hybrid vehicle, essential components are various electrical components including the battery ECU that controls the battery, the blower that cools the battery, the current sensor, temperature sensor and voltage sensor that measure the battery condition, and the wire harnesses that combines such devices.
Such devices are combined in a single package and operated, and designs are carried out to ensure the vibration resistance, impact resistance, resistance to weather, etc., so that the package can be operated safely under the on-board condition.