Abstract: A battery module that includes a battery and a bidirectional DC-DC converter including a switching element that is arranged at a position where heat generated by the switching element is transmitted to the battery. The bidirectional DC-DC converter operates in a discharge mode in which DC power supplied from the battery is converted and supplied to an input/output unit, and in a charge mode in which DC power supplied from the input/output unit is converted and supplied to the battery. Moreover, a control unit forces the bidirectional DC-DC converter to operate in the discharge mode and to increase a switching frequency of the switching element in comparison with a switching frequency in normal driving, when a temperature in a periphery of the battery needs to be increased.

Abstract: A storage device that includes a first switching circuit connected to a direct-current voltage bus and a second switching circuit connected between the first switching circuit and a DC-DC converter. A smoothing capacitor is connected between the DC-DC converter and the switching circuit. Moreover, the second switching circuit includes a pair of relays connected in series between the first switching circuit and the DC-DC converter and an inrush current prevention circuit connected in parallel with the series circuit of the relays. A first voltage sensor is connected to a node between the pair of relays and a second voltage sensor is connected between both terminals of the smoothing capacitor. A control unit determines the presence of welding at the relays on the basis of voltage values detected by the voltage sensors.

Abstract: A battery module that includes a battery and a bidirectional DC-DC converter including a switching element that is arranged at a position where heat generated by the switching element is transmitted to the battery. The bidirectional DC-DC converter operates in a discharge mode in which DC power supplied from the battery is converted and supplied to an input/output unit, and in a charge mode in which DC power supplied from the input/output unit is converted and supplied to the battery. Moreover, a control unit forces the bidirectional DC-DC converter to operate in the discharge mode and to increase a switching frequency of the switching element in comparison with a switching frequency in normal driving, when a temperature in a periphery of the battery needs to be increased.

Abstract: A storage device that includes a first switching circuit connected to a direct-current voltage bus and a second switching circuit connected between the first switching circuit and a DC-DC converter. A smoothing capacitor is connected between the DC-DC converter and the switching circuit. Moreover, the second switching circuit includes a pair of relays connected in series between the first switching circuit and the DC-DC converter and an inrush current prevention circuit connected in parallel with the series circuit of the relays. A first voltage sensor is connected to a node between the pair of relays and a second voltage sensor is connected between both terminals of the smoothing capacitor. A control unit determines the presence of welding at the relays on the basis of voltage values detected by the voltage sensors.