Electrode for secondary batteries, and secondary battery

A secondary battery, comprising:

• an electrode assembly that includes:
• at least a negative electrode that includes:
• a core, wherein the electrode assembly is a wound electrode assembly in which the negative electrode for the secondary battery is spirally wound;
• and
• a mixture layer formed on a surface of the core, wherein
• the mixture layer includes high density regions and low density regions,
• the high density regions and the low density regions are alternately arranged in a first direction of the mixture layer, extend in a second direction perpendicular to the first direction, and are formed in a stripe shape,
• the first direction is perpendicular to a thickness direction of the core and along with an axial direction of the electrode assembly which is a width direction of the negative electrode,
• each of the high density regions and the low density regions includes an active material and a binder, and
• a density of each of the low density regions and a density of each of the high density regions satisfy
• 0.85≤ the density of each of the low density regions/the density of each of the high density regions <0.95;
• an electrolyte solution;
• and
• an outer body housing the electrode assembly.