A negative electrode wherein a negative electrode current collector has a conductive foil including a conductive substrate and a multiplicity of conductive lumpy projections provided at a surface of the substrate is provided. The multiplicity of lumpy projections are so disposed that a plurality of the lumpy projections are aligned substantially in one direction to form a lumpy projection row and that a plurality of the lumpy projection rows are arrayed side by side at a predetermined interval in a direction substantially orthogonal to the one direction.