Packaging material for cell
A packaging material for a cell including a layered film in which at least a base-material layer, an adhesive layer, a metallic layer, and a sealant layer are layered in the stated order. The packaging material for a cell including a layered body in which at least a base-material layer, an adhesive layer, a metallic layer, and a sealant layer are layered in the stated order, wherein the packaging material for a cell can be imparted with highly exceptional moldability, and dramatically less prone to pinholing and cracking during molding by using, as the metallic layer, an aluminum foil having 0.2% yield strength of 58-121 N/mm 2 when a tensile test is performed in the direction parallel to the rolling direction.
1. A packaging material for a cell including a laminate with at least a base material layer, an adhesive layer, a metal layer and a sealant layer laminated in this order, wherein the metal layer is an aluminum foil which, when a tensile test is conducted in a parallel direction with respect to a rolling direction:
has a 0.2% yield strength of 58 to 121 N/mm 2 , and
satisfies a tensile rupture strength of 102 to 130 N/mm 2 .
2. The packaging material for a cell according to claim 1 , wherein the base material layer is a biaxially stretched nylon film that satisfies the following physical properties (i) and (ii):
(i) the elongation in the width direction (EL TD ) is 80 to 120%, and the ratio of the elongation in the flow direction (EL MD ) to the elongation in the width direction (EL TD ) (EL MD /EL TD ) is 1 to 1.25; and
(ii) the tensile strength in the width direction (TS TD ) is 280 MPa or more, and the ratio of the tensile strength in the flow direction (TS MD ) to the tensile strength in the perpendicular direction (TS TD ) (TS MD /TS TD ) is 0.75 to 1.
3. The packaging material for a cell according to claim 1 , wherein the aluminum foil satisfies a 0.2% yield strength of 50 to 130 N/mm 2 when a tensile test is conducted in a perpendicular direction and a 45° direction with respect to a rolling direction.
4. The packaging material for a cell according to claim 1 , wherein at least one of the surfaces of the metal layer is subjected to a chemical conversion treatment.
5. The packaging material for a cell according to claim 1 , wherein the packaging material is a packaging material for a secondary battery.
6. A cell, wherein a cell element including at least a positive electrode, a negative electrode and an electrolyte is stored in the packaging material for a cell according to claim 1 .