Patent ID: 8173287

Claim:
A battery pack comprising: a rechargeable battery; a charging/discharging switching element electrically connected to a high-current path of the rechargeable battery; a conductor electrically connected to the high-current path in which a current for charging/discharging of the rechargeable battery flows; a temperature sensor disposed around the conductor to measure a temperature of the conductor; and a charging/discharging control circuit electrically connected to the rechargeable battery to measure a voltage of the rechargeable battery, electrically connected to two positions of the conductor to measure a voltage between two positions of the conductor, and electrically connected to the temperature sensor to measure the temperature of the conductor; wherein the charging/discharging control circuit is programmed to calculate a charging/discharging current flowing in the conductor by using a previously memorized lookup table for temperature resistance, the measured voltage between the two positions of the conductor, and the temperature measured from the conductor as input signals; and to adjust the charging/discharging current flowing in the charging/discharging switching element according to the previously memorized lookup table for temperature-resistance, the measured voltage between the two positions of the conductor, the voltage of the rechargeable battery and the temperature measured from the conductor.