The present invention provides a nonaqueous electrolyte secondary battery,
comprising an electrode group including a positive electrode, a negative
electrode including a material for absorbing-desorbing lithium ions, and
a separator arranged between the positive electrode and the negative
electrode, a nonaqueous electrolyte impregnated in the electrode group
and including a nonaqueous solvent and a lithium salt dissolved in the
nonaqueous solvent, and a jacket for housing the electrode group and
having a thickness of 0.3 mm or less, wherein the nonaqueous solvent
.gamma.-butyrolactone in an amount larger than 50% by volume and not
larger than 95% by volume based on the total amount of the nonaqueous
solvent.