Disclosed is a battery module having a new voltage detection structure with respect to a plurality of secondary batteries included in a cell assembly. The battery module includes a cell assembly in which a plurality of secondary batteries, each having a plate-shaped electrode lead protruding in a horizontally laid state, are stacked in a vertical direction; and a sensing assembly for sensing voltages of the secondary batteries, the sensing assembly including a plurality of sensing plates made of an electrical conductive material with a horizontally laid plate shape and having one end welded in face-to-face contact with the electrode lead, and a connector electrically connected to the other end of the sensing plates to transmit a sensed voltage.