Abstract: Aspects of the disclosure relate to making it easy to move a power supply device having a large capacity battery. A power supply device includes a carriage, an inverter, a battery and a battery mounting portion. The carriage has wheels. The inverter is supported by the carriage. The battery has a power output terminal at the lower part thereof. The battery mounting portion has a power input terminal which is connected to the inverter and contacts with the output terminal when the battery is mounted. The battery can be mounted and detached by moving vertically.

Abstract: A power supply device and a power supply control method with which charging and electric power supply can be continued efficiently, and a charge capacity can be added is disclosed. A power supply device including: plural battery units replaceably connected to a battery connection part, an output unit for outputting electric power from the battery unit to a load, and a control unit for controlling connection of the plural battery units with respect to the output unit, wherein the control unit selects a battery unit having a remaining charge amount that is smallest among the plural battery units and equal to or greater than a first predetermined amount, and connects the selected battery unit to the output unit.

Abstract: To provide a power supply device and a power supply control method with which charging and electric power supply can be continued efficiently, and a charge capacity can be added. A power supply device including: plural battery units replaceably connected to a battery connection part, an output unit for outputting electric power from the battery unit to a load, and a control unit for controlling connection of the plural battery units with respect to the output unit, wherein the control unit selects a battery unit having a remaining charge amount that is smallest among the plural battery units and equal to or greater than a first predetermined amount, and connects the selected battery unit to the output unit.

Abstract: A charging device is provided, which is capable of starting up a control circuit without any separate power supply so as to start an appropriate charge operation even when a secondary battery is in an overdischarged state. A charging device to charge a secondary battery with electric power generated by a solar cell includes: a charging control unit that controls the electric power generated by the solar cell to have a current value and/or a voltage value suitable for charging, and that supplies the controlled electric power to the secondary battery; and a start-up control unit that supplies, to the charging control unit, a boosted power source by boosting the electric power from the solar cell when charging is started, and that starts up the a charging control unit.

Abstract: Aspects of the disclosure relate to making it easy to move a power supply device having a large capacity battery. A power supply device includes a carriage, an inverter, a battery and a battery mounting portion. The carriage has wheels. The inverter is supported by the carriage. The battery has a power output terminal at the lower part thereof. The battery mounting portion has a power input terminal which is connected to the inverter and contacts with the output terminal when the battery is mounted. The battery can be mounted and detached by moving vertically.

Abstract: A charging device is provided, which is capable of starting up a control circuit without any separate power supply so as to start an appropriate charge operation even when a secondary battery is in an overdischarged state. A charging device to charge a secondary battery with electric power generated by a solar cell includes: a charging control unit that controls the electric power generated by the solar cell to have a current value and/or a voltage value suitable for charging, and that supplies the controlled electric power to the secondary battery; and a start-up control unit that supplies, to the charging control unit, a boosted power source by boosting the electric power from the solar cell when charging is started, and that starts up the a charging control unit.