| 摘要 |
<p>PROBLEM TO BE SOLVED: To restrain difference among residual charge rates of single batteries in a battery pack, enable discharge while a battery pack voltage is ensured, and restrain temperature rise of the battery pack independent of operation. SOLUTION: Voltage difference is obtained by detecting a voltage of each single battery in a state of discharge. When the obtained is at least a previously set reference value or exceeds it, single batteries on a low voltage side generating the voltage difference are disconnected. In the state that the voltage difference between single batteries is restrained, the battery pack is discharged. A cooling fan is connected with a thermoelectric element whose heat generating surface is fixed to the battery pack or a case of the battery pack, and driven by produced power of the thermoelectric element.</p> |
