| 摘要 |
PROBLEM TO BE SOLVED: To provide a metal exterior case material for a lithium ion battery case material in which elution of Fe ion during an aging process is small, and elution of Ni ion is suppressed even under a high potential of 4 V or more when connected to a negative electrode, and which has a high interior corrosion resistivity even after charging and discharging for a long period of time when connected neutrally, and furthermore in which an increase in the material cost is small, and besides, a change in the manufacturing process is not necessary, and provide the metal exterior case and the lithium ion battery in which the metal exterior case is used.SOLUTION: The metal exterior case material is based on a cold rolled steel sheet as a ground, and has a Cu-Ni diffusion layer, an Ni layer, a metal Cr or Cu layer, a Cu-Ni diffusion layer, an Ni layer, and a metal Cr layer from the lower layer side on the face corresponding to the case interior face. Furthermore, preferably this has an Fe-Ni layer or an Fe-Cu-Ni layer in the middle of the cold rolled steel sheet and the Cu-Ni layer, and an Fe-Ni layer or an Fe-Cu-Ni layer in the middle of the cold rolled steel sheet and the Cu layer. |
