NOVELTY - A secondary battery comprises a nonaqueous electrolyte, a positive electrode (21) and a negative electrode (22). The negative electrode comprises negative electrode active material layer comprising inorganic compound which occlude-discharges an electrode reaction substance at electric potential (electric potential for lithium) of 1-3 V, and a metal salt containing sulfonic-acid-type compounds (I) and (II).    USE - Secondary battery is used for battery pack, electric vehicle, electric power storage system, electric tool, and electronic device (all claimed). Uses include but are not limited to video camera, digital still camera, mobile telephone, notebook computer, cordless telephone apparatus, headphone stereo cassette tape recorder, portable radio, portable television, portable information terminal, electric shaver, backup power supply and memory card, electric drill, electric saw, pacemaker, hearing aid, and hybrid vehicle.    ADVANTAGE - The secondary battery is lightweight, and has high energy density.    DETAILED DESCRIPTION - A secondary battery comprises a nonaqueous electrolyte, a positive electrode and a negative electrode. The negative electrode comprises negative electrode active material layer comprising electrode compound which occlude-discharges an electrode reaction substance at electric potential (electric potential for lithium) of 1-3 V, and a metal salt containing sulfonic-acid-type compounds of formulae (I) and (II).    M,M'=alkali metal or alkaline-earth metal element;    a,e=1 or more;and    b-d,f-h=1 or 2.    INDEPENDENT CLAIMS are included for the following:    (1) negative electrode;    (2) battery pack, which comprises secondary battery, a control portion which controls operation of the secondary battery, and a switch portion which switches operation of the secondary battery based on instruction of the control portion;    (3) electric vehicle, which comprises secondary battery, a conversion portion which converts electric power supplied from the secondary battery into driving force, a drive portion driven based on the driving force, and a control portion which controls operation of the secondary battery;    (4) electric power storage system, which comprises secondary battery, an electric equipment to which electric power is supplied from the secondary battery, and a control portion which controls the electric power supply with respect to the electric equipment from the said secondary battery;    (5) electric tool, which comprises secondary battery, and a movable portion to which electric power is supplied from the secondary battery; and    (6) electronic device, which comprises secondary battery and an electric power supply source.    DESCRIPTION OF DRAWING(S) - The drawing shows a sectional view of the secondary battery using the negative electrode. (Drawing includes non-English language text)    Battery Can (11)    Insulation board (12,13)    Positive electrode (21)    Negative electrode (22)    Separator (23)