A secondary battery comprising: an electrode assembly comprising a positive electrode plate having a positive electrode non-coating portion , a negative electrode plate having a negative electrode non-coating portion , and a separator between the positive electrode plate and the negative electrode plate , the positive electrode non-coating portion and the negative electrode non-coating portion being exposed at opposite sides of the electrode assembly ; a case having a top opening and an internal space accommodating the electrode assembly ; a cap plate sealing the top opening of the case ; a positive electrode current collector plate perpendicular to the positive electrode non-coating portion and welded to the positive electrode non-coating portion ; a negative electrode current collector plate perpendicular to the negative electrode non-coating portion and welded to the negative electrode non-coating portion ; a positive electrode terminal on the cap plate and electrically connected to the positive electrode current collector plate ; a negative electrode terminal on the cap plate and electrically connected to the negative electrode current collector plate , wherein the electrode assembly further comprises a second separator , and the positive electrode plate , the separator , the negative electrode plate , and the second separator are sequentially stacked along a Y-axis direction, and wherein a laser welding line joining the positive electrode current collector plate to the positive electrode non-coating portion is formed along the Y-axis direction, and a laser welding line joining the negative electrode current collector plate to the negative electrode non-coating portion is formed along the Y-axis direction, and wherein the positive electrode non-coating portion is in line-contact with the positive electrode current collector plate and the negative electrode non-coating portion is in line-contact with the negative electrode current collector plate . an electrode assembly comprising a positive electrode plate having a positive electrode non-coating portion , a negative electrode plate having a negative electrode non-coating portion , and a separator between the positive electrode plate and the negative electrode plate , the positive electrode non-coating portion and the negative electrode non-coating portion being exposed at opposite sides of the electrode assembly ; a case having a top opening and an internal space accommodating the electrode assembly ; a cap plate sealing the top opening of the case ; a positive electrode current collector plate perpendicular to the positive electrode non-coating portion and welded to the positive electrode non-coating portion ; a negative electrode current collector plate perpendicular to the negative electrode non-coating portion and welded to the negative electrode non-coating portion ; a positive electrode terminal on the cap plate and electrically connected to the positive electrode current collector plate ; a negative electrode terminal on the cap plate and electrically connected to the negative electrode current collector plate , wherein the electrode assembly further comprises a second separator , and the positive electrode plate , the separator , the negative electrode plate , and the second separator are sequentially stacked along a Y-axis direction, and wherein a laser welding line joining the positive electrode current collector plate to the positive electrode non-coating portion is formed along the Y-axis direction, and a laser welding line joining the negative electrode current collector plate to the negative electrode non-coating portion is formed along the Y-axis direction, and wherein the positive electrode non-coating portion is in line-contact with the positive electrode current collector plate and the negative electrode non-coating portion is in line-contact with the negative electrode current collector plate . <EOS>