BATTERY PACK

Provided is a battery pack that is charged by being connected to a charger and discharged by being connected to a load, the battery pack including: a charge-discharge terminal including a positive electrode terminal, a negative electrode terminal, and a temperature terminal; a secondary battery that is charged and discharged through the positive electrode terminal and the negative electrode terminal; a current measurement unit that measures a charge-discharge current of the secondary battery; a thermistor which is connected to the temperature terminal and which measures a battery temperature of the secondary battery; a voltage switching unit that intermittently outputs to the temperature terminal an applied voltage that causes the thermistor to operate; and a control unit that recognizes a connected state of the charge-discharge terminal on the basis of the voltage at the temperature terminal in an on-period and an off-period of the applied voltage, and the charge-discharge current.