| 摘要 |
PURPOSE:To compensate a voltage drop by adding a separated cell in a combination battery in compliance with a battery temperature change or terminal voltage change in a secondary battery pack wherein a plurality of secondary batteries such as an Ni-Cd battery are connected to each other in series. CONSTITUTION:The pack is provided with: a secondary battery combination cell 2 composed of a plurality of cells and used at all times; a secondary battery additional cell 3 which is a cell separated from the combination cell 2 and used additionally at the time of emergency; a temperature sensor 6 installed inside for measuring a battery surface temperature; a voltage drop comparator 4 for monitoring a voltage drop at the time of discharging under an ordinary temperature; and a temperature change comparator 5 for monitoring a temperature drop at the time of full charge. A voltage drop due to internal resistance increase at a low temperature in the temperature sensor 6 at the time of a low temperature and full charge is detected by the comparator 5 so as to add the additional cell 3 to the combination cell 2 for output. At the time of an ordinary temperature and discharge, a voltage drop in the combination cell 2 is detected by the comparator 4 so as to add the additional cell 3 to the combination cell 2 for output. |
