CPC H01M 4/661 (2013.01) [H01M 4/131 (2013.01); H01M 4/666 (2013.01); H01M 4/667 (2013.01); H01M 10/0525 (2013.01); H01M 10/0585 (2013.01)] | 7 Claims |
1. A non-aqueous electrolyte secondary battery, comprising:
a positive electrode, a negative electrode, and a non-aqueous electrolyte,
the positive and negative electrodes each including a current collector and a mixture layer formed on a surface of the current collector;
the current collector including a resin layer and metallic foils provided on both surfaces of the resin layer in at least one of the positive and negative electrodes; and
a surface of the metallic foils on which the mixture layer is formed being roughened;
wherein an average X (μm) of thicknesses x of the thinnest parts and an average Y (μm) of thicknesses y of the thickest parts of the metallic foils determined based on a plurality of obtained sectional SEM images in a stacked direction of the resin layer and the metallic foils satisfy the following relationship:
0.1<μm<X<4 μm, and
1.2≤Y/X,
wherein the resin layer includes a resin having a melting point of 265° C. or lower under 1 atm, the resin being polyethylene terephthalate (PET), and
wherein the metallic foils are copper foils.
|