Abstract: A battery pack (1) includes: a battery stack (20) in which a plurality of laminar battery cells (10) are connected in series; a voltage monitoring unit (3) that monitors the voltage of each battery cell; a power unit (4) that has power lines (41p, 41n) for connecting the battery stack (20) and external connection terminals (42p, 42n), a current monitoring unit (44) for monitoring the current of the power lines, and a switch (43) for disconnecting the power lines; and a control unit (5) that receives signals from the voltage monitoring unit and the current monitoring unit, and outputs to the switch a signal for shutting off the power line. The power unit (4) is provided on a power board (74) separately from boards (73, 75) on which the voltage monitoring unit (3) and the control unit (5) are provided. Wiring formed on the power board (74) is thicker than that formed on the boards (73, 75) on which the voltage monitoring unit and the control unit are provided.

Abstract: A battery pack (1) includes: a battery stack (20) in which a plurality of laminar battery cells (10) are connected in series; a voltage monitoring unit (3) that monitors the voltage of each battery cell; a power unit (4) that has power lines (41p, 41n) for connecting the battery stack (20) and external connection terminals (42p, 42n), a current monitoring unit (44) for monitoring the current of the power lines, and a switch (43) for disconnecting the power lines; and a control unit (5) that receives signals from the voltage monitoring unit and the current monitoring unit, and outputs to the switch a signal for shutting off the power line. The power unit (4) is provided on a power board (74) separately from boards (73, 75) on which the voltage monitoring unit (3) and the control unit (5) are provided. Wiring formed on the power board (74) is thicker than that formed on the boards (73, 75) on which the voltage monitoring unit and the control unit are provided.