Nonaqueous electrolyte secondary cell

The present invention provides a nonaqueous electrolyte secondary cell using, as a cell casing, a film-like casing, in which pressure exerted by the structure of the casing is low, and a gel electrolyte including a polymer, a nonaqueous solvent, and an electrolyte salt. The cell inhibits an internal short-circuit caused by heat shrinkage of a separator and improves safety of the cell, by, for example, making the construction one in which the heat shrinkage rate in the width direction of the separator when heated to 130° C. is controlled to 50% or less and the weight percentage of the polymer in relation to the total weight of a component of the nonaqueous solvent with a boiling point of over 130° C. and the polymer is controlled to 5% or more