NOVELTY - The rectangular non-aqueous electrolyte lithium ion secondary battery comprises a metallic outer can (1), a wound electrode group (2) accommodated in the outer can in a direction perpendicular to a winding axis, a positive electrode-lead (3) connected to a wound positive electrode current-collecting tab, a negative electrode-lead (4) connected to a wound negative electrode current-collecting tab, a metallic lid that comprises a positive electrode terminal (6) and a negative electrode terminal and is attached to an opening portion of the outer can, and a positive electrode insulating cover.    USE - The rectangular non-aqueous electrolyte lithium ion secondary battery is useful as a power source for electric cars, hybrid vehicles, electric motors and forklifts.    ADVANTAGE - The highly safe sealed rectangular non-aqueous electrolyte lithium ion secondary battery has high energy density, reduced weight, and good electrical characteristics.    DETAILED DESCRIPTION - The rectangular non-aqueous electrolyte lithium ion secondary battery comprises a metallic outer can (1), a wound electrode group (2) accommodated in the outer can in a direction perpendicular to a winding axis, a positive electrode-lead (3) connected to a wound positive electrode current-collecting tab, a negative electrode-lead (4) connected to a wound negative electrode current-collecting tab, a metallic lid that comprises a positive electrode terminal (6) and a negative electrode terminal and is attached to an opening portion of the outer can, a positive electrode insulating cover engaged with one end portion including the positive electrode current-collecting tab, a negative electrode insulating cover engaged with the other end portion including the negative electrode current-collecting tab, and a rectangular protruding portion. The wound positive electrode current-collecting tab is provided at one end of the wound electrode group, and the wound negative electrode current-collecting tab is provided at the other end of the wound electrode group. The positive electrode-lead comprises a connection portion connected to the positive electrode terminal, and first and second sandwiching portions that extend from the connection portion to the wound electrode group in the direction perpendicular to the winding axis to sandwich the wound positive electrode current-collecting tab. The negative electrode-lead comprises a connection portion connected to the negative electrode terminal, and first and second sandwiching portions that extend from the connection portion to the wound electrode group in the direction perpendicular to the winding axis to sandwich the wound negative electrode current-collecting tab. The positive electrode insulating cover comprises: a U-shaped member that has first and second sidewalls facing each other; a back surface member; and a member to sandwich the first sandwiching portion of the positive electrode-lead and the wound positive electrode current-collecting tab portion that faces the first sandwiching portion and to sandwich the second sandwiching portion of the positive electrode-lead and the positive electrode current-collecting tab portion that faces the second sandwiching portion. The negative electrode insulating cover comprises: a U-shaped member that has first and second sidewalls facing each other; a back surface member; and a member to sandwich the first sandwiching portion of the negative electrode-lead and the wound negative electrode current-collecting tab portion that faces the first sandwiching portion and to sandwich the second sandwiching portion of the negative electrode-lead and the negative electrode current-collecting tab portion that faces the second sandwiching portion. The negative electrode insulating cover is formed of an insulating material. Each of the sandwiching members of the positive electrode insulating cover and the negative electrode insulating cover comprises a rectangular thick portion provided on each of the first and second sidewalls facing each other. The rectangular protruding portion is provided on the back surface member. The protruding portion is located between the thick portions, and a length from the back surface member to a surface opposite to the member is less than a width of the sidewall of the U-shaped member. The first and second sidewalls are bent outwardly. Each of the sandwiching members of the positive and negative electrode insulating covers comprises bent sidewalls. The protruding portion is further located between the bent sidewalls. The U-shaped member of each of the positive and negative electrode insulating covers comprises an extending portion that extends from a bent portion in a direction opposite to the back surface member. The extending portion comprises a channel groove that extends in parallel with the extending portion.    DESCRIPTION OF DRAWING(S) - The diagram shows a schematic perspective view of a battery.    Metallic outer can (1)    Wound electrode group (2)    Positive electrode-lead (3)    Negative electrode-lead (4)    Positive electrode terminal. (6)