A battery module, comprising: a cell assembly having a plurality of secondary batteries; a battery management unit having a printed circuit board with a printed circuit, the printed circuit board having a connecting portion on inner and outer peripheries of which a connecting conductor (213c1) is coated to be electrically connected to the printed circuit, wherein the connecting portion has a connecting groove (213h1) formed so that a part of the printed circuit board is dented inward; a bus bar plate having a plate shape, the bus bar plate having a connection portion configured to electrically connect the plurality of secondary batteries and a sensing portion with a strip form elongated from one side end of the connection portion, and a module housing having an inner space formed therein to accommodate the cell assembly, wherein an insert groove dented inward is formed at an outer surface of the module housing so that a part of the sensing portion extending from the connection portion is inserted and fixed therein; wherein the sensing portion includes: a fixed part inserted into the insert groove formed at the outer surface of the module housing; an upright part bent upward from an extended longitudinal end of the fixed part to protrude outward; and a connecting part connected to an extended longitudinal end of the upright part and having a bent structure that is bent at least two times in an inner direction, or in an outer direction, or in an inner direction and an outer direction, the bent structure having a top portion that is in pressure contact with the connecting portion, wherein the bent structure of the sensing portion has a bent shape to have a sharp shape in the upper direction, and an upper part of the bent structure of the sensing portion is located to fit into the connecting groove (213h1). a cell assembly having a plurality of secondary batteries; a battery management unit having a printed circuit board with a printed circuit, the printed circuit board having a connecting portion on inner and outer peripheries of which a connecting conductor (213c1) is coated to be electrically connected to the printed circuit, wherein the connecting portion has a connecting groove (213h1) formed so that a part of the printed circuit board is dented inward; a bus bar plate having a plate shape, the bus bar plate having a connection portion configured to electrically connect the plurality of secondary batteries and a sensing portion with a strip form elongated from one side end of the connection portion, and a module housing having an inner space formed therein to accommodate the cell assembly, wherein an insert groove dented inward is formed at an outer surface of the module housing so that a part of the sensing portion extending from the connection portion is inserted and fixed therein; wherein the sensing portion includes: a fixed part inserted into the insert groove formed at the outer surface of the module housing; an upright part bent upward from an extended longitudinal end of the fixed part to protrude outward; and a connecting part connected to an extended longitudinal end of the upright part and having a bent structure that is bent at least two times in an inner direction, or in an outer direction, or in an inner direction and an outer direction, the bent structure having a top portion that is in pressure contact with the connecting portion, wherein the bent structure of the sensing portion has a bent shape to have a sharp shape in the upper direction, and an upper part of the bent structure of the sensing portion is located to fit into the connecting groove (213h1). a fixed part inserted into the insert groove formed at the outer surface of the module housing; an upright part bent upward from an extended longitudinal end of the fixed part to protrude outward; and a connecting part connected to an extended longitudinal end of the upright part and having a bent structure that is bent at least two times in an inner direction, or in an outer direction, or in an inner direction and an outer direction, the bent structure having a top portion that is in pressure contact with the connecting portion, wherein the bent structure of the sensing portion has a bent shape to have a sharp shape in the upper direction, and an upper part of the bent structure of the sensing portion is located to fit into the connecting groove (213h1).