A nonaqueous secondary battery 10 of the invention has an active material
compound layer 14 deposed over at least one face of a collector 12 made
of metal foil and is equipped with a positive electrode 11 having a
portion 13 in a part of which metal is exposed. The positive electrode 11
together with the exposed-metal portion 13 faces a negative electrode 17
through an interposed separator 23, and on that part of the exposed-metal
portion 13 that faces the negative electrode 17 through the interposed
separator 23 there is formed a protective layer 16 made of a material
whose electronic conductivity is lower than that of the metal and which
moreover is non-insulative. With such nonaqueous secondary battery 10,
should part of an electrode pierce the separator and contact with the
other electrode, the battery will be gently discharged, thereby averting
abnormal heat generation by the battery and additionally enabling the
battery's abnormality to be sensed by the equipment via the fall in
battery voltage. Thus, there is provided a nonaqueous secondary battery
of excellent safety that can prevent abnormal heat generation due to a
short circuit caused by burr, powder or the like piercing the separator.