| 摘要 |
PURPOSE:To detect the residual capacity of a battery when it is left with high precision by judging whether the battery before it is left is in a charged condition or in a discharged condition in accordance with the change of battery voltage after it is left. CONSTITUTION:A voltage detector 18 detects voltage (battery voltage) E between the terminals of a battery 12. An electronic control unit(ECU) 22 computes the residual capacity of the battery 12 in accordance with detection data output from the detector 18, a current detector 16, etc. Judgement whether the battery 12 immediately before it is left is in a charged condition or in a discharged condition in accordance with the change of the voltage E certain time immediately after it is left is made. When it is in a charge mode immediately before it is left, the residual capacity before correction is found by using the detected voltage E, and when it is in a discharge mode immediately before it is left, the residual capacity before correction is found by using the predicted voltage E after stabilized. In this way, the residual capacity before correction is prevented from being computed higher than an actual residual capacity. |
