| 摘要 |
A battery module 100 includes a lithium ion secondary battery 200 and a control circuit 300. The control circuit 300 includes a measurement unit 310 which measures a voltage, a current, and a time of charge/discharge of the lithium ion secondary battery 200, an operation unit 320 which calculates a capacity Q on the basis of the voltage, the current, and the time and calculates a differential value dQ/dV by differentiating the capacity Q with a voltage V, a threshold voltage setting unit 330 which specifies a peak of a low capacity side of the differential value dQ/dV generated on the basis of a stage structure of graphite and sets a voltage at the peak to a threshold voltage, a cutoff voltage setting unit 340 which sets a discharge cutoff voltage of the lithium ion secondary battery 200 on the basis of the threshold voltage, and a charge/discharge control unit 360 which controls the charge/discharge of the lithium ion secondary battery 200 on the basis of the discharge cutoff voltage. |
