Apparatus for estimating state of secondary battery, and battery pack including the same

An apparatus for estimating a state of a secondary battery, connectable to a positive electrode lead, a negative electrode lead, a first measuring lead, and a second measuring lead included in the secondary battery, the apparatus comprising:

• a terminal case including:
• a plurality of inner terminals, each configured to be contactable with the positive electrode lead, the negative electrode lead, the first measuring lead, or the second measuring lead on a first surface of the terminal case;
• and
• a plurality of outer terminals configured to be respectively electrically connectable to the plurality of inner terminals on a second surface facing the first surface of the terminal case;
• a voltage measuring circuit configured to:
• be electrically connected to at least two of the plurality of outer terminals;
• and
• measure a potential difference between the first measuring lead and the second measuring lead;
• and
• a control circuit configured to estimate a state of health of the secondary battery based on the potential difference between the first measuring lead and the second measuring lead measured by the voltage measuring circuit,
• wherein:
• the plurality of inner terminals includes inner charging/discharging terminals;
• and
• the inner charging/discharging terminals include:
• a first inner positive electrode terminal configured to be connectable to each of the first measuring lead, the second measuring lead, and the positive electrode lead;
• and
• a first inner negative electrode terminal configured to be connectable to the negative electrode lead.