| 摘要 |
<p>An objective is to estimate an internal resistance of an electric storage device. A battery pack includes a current measurement portion, a voltage measurement portion, and a CPU. The current measurement portion is configured to measure a current value I of a current flowing through a cell. The voltage measurement portion is configured to measure a voltage value V of a voltage across the cell, which is a voltage in charge time. The CPU is configured to estimate an internal resistance of the cell based on the current value I and the voltage value V measured in a ramp region LA of the charge time in which a time variation ”I in current value I is maintained constant. In the battery pack, the internal resistance of the cell can be accurately estimated during the charge time because the time variation ”I in current value I is maintained constant in the ramp region LA.</p> |
