A secondary battery pack comprising: a battery cell configured to have a structure in which an electrode assembly of a cathode/separator/anode structure is mounted in a battery case together with an electrolyte in a sealed state, the battery case is provided at the top thereof with a first electrode terminal, a second electrode terminal and a pair of coupling grooves, one of the coupling grooves is formed at the first electrode terminal, and the second electrode terminal protrudes from the center of the top of the battery case; a protection circuit module comprising a printed circuit board having a protection circuit formed thereon, connection members A and B connected to the first electrode terminal and the second electrode terminal, respectively, and a safety element; and an electrically insulated top cap mounted to the top of the battery cell so as to surround the PCM, the top cap having through holes communicating with the respective coupling grooves, wherein the connection member A is coupled to the bottom of the PCB in a state in which the connection member A protrudes from one end of the PCB in the lateral direction so that a connection portion of the connection member A connected to the first electrode terminal of the battery cell is exposed through a corresponding one of the through holes formed at the top cap, a coupling hole is formed at the protruding portion of the connection member A, and a connection portion of the connection member B connected to the second electrode terminal of the battery cell is located at the bottom of the PCB so that the connection member B is electrically connected to the second electrode terminal via the safety element, and wherein coupling members are coupled into the respective coupling grooves of the battery cell through the through holes of the top cap in a state in which the PCM and the top cap are disposed at the top of the battery cell, and the connection member A is mechanically coupled and electrically connected to the first electrode terminal by a corresponding one of the coupling members, and wherein a connection terminal connected to the second electrode terminal is formed at a position of the bottom of the PCB opposite to the connection member A. a battery cell configured to have a structure in which an electrode assembly of a cathode/separator/anode structure is mounted in a battery case together with an electrolyte in a sealed state, the battery case is provided at the top thereof with a first electrode terminal, a second electrode terminal and a pair of coupling grooves, one of the coupling grooves is formed at the first electrode terminal, and the second electrode terminal protrudes from the center of the top of the battery case; a protection circuit module comprising a printed circuit board having a protection circuit formed thereon, connection members A and B connected to the first electrode terminal and the second electrode terminal, respectively, and a safety element; and an electrically insulated top cap mounted to the top of the battery cell so as to surround the PCM, the top cap having through holes communicating with the respective coupling grooves, wherein the connection member A is coupled to the bottom of the PCB in a state in which the connection member A protrudes from one end of the PCB in the lateral direction so that a connection portion of the connection member A connected to the first electrode terminal of the battery cell is exposed through a corresponding one of the through holes formed at the top cap, a coupling hole is formed at the protruding portion of the connection member A, and a connection portion of the connection member B connected to the second electrode terminal of the battery cell is located at the bottom of the PCB so that the connection member B is electrically connected to the second electrode terminal via the safety element, and wherein coupling members are coupled into the respective coupling grooves of the battery cell through the through holes of the top cap in a state in which the PCM and the top cap are disposed at the top of the battery cell, and the connection member A is mechanically coupled and electrically connected to the first electrode terminal by a corresponding one of the coupling members, and wherein a connection terminal connected to the second electrode terminal is formed at a position of the bottom of the PCB opposite to the connection member A.