Patent ID: 9658293
Date: 2017-05-23
CPC Classifications: G01R,H02J

Claim:
1. A power supply unit comprising: a charging and discharging battery; a current detector configured to measure a current charging or discharging the battery; a voltage detector configured to measure a voltage of the battery; and a remaining capacity meter configured to indicate a remaining capacity of the battery based on the current detected by the current detector and the voltage detected by the voltage detector, wherein the voltage detector outputs the measured voltage of the battery to the remaining capacity meter, and the current detector outputs the measured current of the battery to the remaining capacity meter, a remaining capacity controller, in communication with the remaining capacity meter, the remaining capacity controller comprising: a first voltage meter to determine a first open circuit terminal voltage Voc1 based on a plurality of values of the current input from the current detector and a plurality of values of the voltage input from the voltage detector, a first remaining capacity value being based on the first open circuit terminal voltage Voc1; a second voltage meter to determine a second open circuit terminal voltage Voc2 based on values of the current input from the current detector and values of the voltage input from the voltage detector, a voltage drop Vo by an ohmic resistance Ro, and a voltage drop Vp by a polarization resistance Rp, a second remaining capacity value being based on the second open circuit terminal voltage Voc2; an integrator to determine a third remaining capacity value based on an integration of a detected current input from the current detector; and a summer to determine the remaining capacity [SOC (%)] of the battery by weighted-averaging the first remaining capacity [SOCv1(%)], the third remaining capacity [SOCi (%)], and the second remaining capacity [SOCv2(%)] in the following equation where, A, B, and C are constants, A is equal to or more than 0, B is equal to or more than 0, C is more than 0, A+B+C=1, and at least one of A and B is more than 0.