A connection part which connects a terminal part and a processing part include an equalization resistor that is inserted into each main line and a 0-Ω resistor that is a short circuit line for short circuiting a main line of a first terminal and a main line of a second terminal. In the terminal part, the second terminal s unused, and a battery cell adjacent to a high-potential side of a stack bar is connected between the first terminal and a third terminal.