Patent ID: 7609028

Claim:
A medium- or large-sized secondary battery module which has a plurality of secondary unit cells mounted therein, comprising: a plurality of unit cells, which are chargeable and dischargeable secondary cells; a rectangular lower case having a lower receiving part, to which a main board assembly is attached, and an upper receiving part, on which the unit cells are sequentially stacked one on another; a rectangular upper case having a lower receiving part for covering an upper end of the unit cells stacked on the lower case; a first circuit unit for performing the electrical connection between the stacked unit cells, the first circuit unit including a sensing board assembly for sensing a voltage, a current and/or a temperature of the unit cells; a second circuit unit electrically connected to the first circuit unit, the second circuit unit including a main board assembly for controlling the battery module; and a third circuit unit electrically connected to the second circuit unit, the third circuit unit having switching elements for controlling the operation of the battery module when the abnormal operation of the battery module, such as overcharge, overdischarge, overcurrent, or overheating, occurs; wherein a sensing board assembly comprises: connecting members for electrically connecting electrode terminals of the unit cells with each other, each of the connecting members including a connecting extension part, by which the connecting members are connected to a printed circuit board; and the printed circuit board having drilled-holes, through which the connecting extension parts of the connecting members are securely inserted, and circuits connected to the drilled-holes.