A pouched lithium secondary battery including a battery unit having a positive electrode plate, a negative electrode plate, and a separator disposed between the positive electrode plate and the negative electrode plate; a positive electrode tab electrically connected with the positive electrode plate; a negative electrode tab electrically connected with the negative electrode plate; a case having a space to accommodate the battery unit, and a sealing edge around the space; and a positive electrode voltage applying unit to apply a positive electrode voltage to both the positive electrode tab and the case.