Power supply device

A power supply device comprising:

• a first positive electrode-side battery terminal and a first negative electrode-side battery terminal for connecting a battery;
• a second positive electrode-side battery terminal and a second negative electrode-side battery terminal for connecting a battery;
• a positive electrode-side input terminal and a negative electrode-side input terminal for connecting a charger;
• a positive electrode-side output terminal and a negative electrode-side output terminal for connecting a load;
• a first switch;
• a second switch;
• and
• a third switch, wherein
• the positive electrode-side input terminal is connected to the first positive electrode-side battery terminal,
• the negative electrode-side input terminal is connected to the second negative electrode-side battery terminal,
• the first switch is connected between the first negative electrode-side battery terminal and the second positive electrode-side battery terminal,
• the second switch is connected between a first connection point and the second positive electrode-side battery terminal, the first connection point being between the positive electrode-side input terminal and the first positive electrode-side battery terminal,
• the third switch is connected between the first negative electrode-side battery terminal and a second connection point, the second connection point being between the negative electrode-side input terminal and the second negative electrode-side battery terminal,
• the positive electrode-side output terminal is connected to a line that connects the positive electrode-side input terminal and the first positive electrode-side battery terminal, and
• the negative electrode-side output terminal is connected to a line that connects the first negative electrode-side battery terminal and the third switch.

A power supply device comprising:

• a first positive electrode-side battery terminal and a first negative electrode-side battery terminal for connecting a battery;
• a second positive electrode-side battery terminal and a second negative electrode-side battery terminal for connecting a battery;
• a positive electrode-side input terminal and a negative electrode-side input terminal for connecting a charger;
• a positive electrode-side output terminal and a negative electrode-side output terminal for connecting a load;
• a first switch;
• a second switch;
• and
• a third switch, wherein
• the positive electrode-side input terminal is connected to the first positive electrode-side battery terminal,
• the negative electrode-side input terminal is connected to the second negative electrode-side battery terminal,
• the first switch is connected between the first negative electrode-side battery terminal and the second positive electrode-side battery terminal,
• the second switch is connected between a first connection point and the second positive electrode-side battery terminal, the first connection point being between the positive electrode-side input terminal and the first positive electrode-side battery terminal,
• the third switch is connected between the first negative electrode-side battery terminal and a second connection point, the second connection point being between the negative electrode-side input terminal and the second negative electrode-side battery terminal,
• the second switch and the third switch are constituted of two switching elements connected in series,
• the positive electrode-side output terminal is connected to a line that connects the two switching elements constituting the second switch, and
• the negative electrode-side output terminal is connected to a line that connects the two switching elements constituting the third switch.