BATTERY CURRENT DETECTOR, AND ELECTRIC VEHICLE AND POWER STORAGE DEVICE EQUIPPED WITH CURRENT DETECTOR

摘要

To eliminate an error due to the thermal electromotive force of different kinds of metal and detect a battery current with extremely high accuracy.SOLUTION: A current detector comprises: a shunt resistor 2 created by connecting, to an output terminal 22, a resistive element 21 of different kinds of metal differing from the output terminal part 22 in electric conductivity; a voltage detection circuit 3 for detecting a voltage drop of the shunt resistor 2; a main temperature detector 4 for detecting the temperature of a first edge 2A of the shunt resistor 2; a sub-temperature detector 5 for detecting the temperature of a second edge 2B of the shunt resistor 2; a thermal electromotive force detection circuit 6 for specifying the thermal electromotive force of the shunt resistor 2 from the detected temperatures of the main temperature detector 4 and sub-temperature detector 5; and a current computation circuit 8 for computing a current value flowing in the shunt resistor 2 from the voltage drop detected by the voltage detection circuit 3, the thermal electromotive force specified by the thermal electromotive force detection circuit 6 and the resistance value of the shunt resistor 2.SELECTED DRAWING: Figure 1