BATTERY
This battery is provided with: an electrode assembly ( 20 ) resulting from stacking a positive electrode, a negative electrode, and a separator arranged between the positive electrode and the negative electrode, and an external sheathing film ( 12 ) composed of a pair of resin layers, of which outer peripheries are heat-welded together, and that sandwich the electrode assembly ( 20 ). At least one of the electrode assembly has a protruding part ( 24 ) that protrudes from the electrodes, and is interposed at a peripheral area by the welded portion of the external sheathing film ( 12 ), and that restrains movement of the separators.
1 . A battery comprising:
an electrode assembly resulting from stacking a positive electrode, a negative electrode, and a separator arranged between the positive electrode and the negative electrode, and
an external sheathing film that is composed of a pair of resin layers, of which outer peripheries are heat-welded together, and that sandwich the electrode assembly;
wherein at least one separator of the electrode assembly has a protruding part that protrudes from the electrodes,
and is interposed at a peripheral area by a welded portion of the external sheathing film, and that restrains movement of the separators.
2 . The battery according to claim 1 ,
wherein the protruding part restrains movement of the separators in both forward and backward direction of the protrusion.
3 . The battery according to claim 1 ,
wherein the protruding part comprises:
a clamped part that restrains movement of the separator; and
a connecting part that connects the clamped part and a main body of the separator other than the protruding part.
4 . The battery according to claim 3 ,
wherein the length of the clamped part in a direction that is substantially perpendicular to the direction of the protrusion is longer than the length of the connecting part in a direction that is substantially perpendicular to the direction of the protrusion.
5 . The battery according to claim 1 ,
wherein the thickness of the protruding part is greater than or equal to 60 μm and less than or equal to 200 μm.
6 . The battery according to claim 1 ,
wherein the separator is interposed by the welded portion of the external sheathing film over a width of greater than or equal to 2 mm at the peripheral area.
7 . The battery according to claim 1 ,
further comprising lead parts connected to the electrode assembly and provided for connecting to the outside; and
of the external sheathing film, the width of the portion that is heat-welded along the side having the lead parts is greater than or equal to 5 mm.
8 . The battery according to claim 1 ,
wherein the separator is selected from a separator containing aromatic polyamide resin or a ceramic-coated separator.