Abstract: An electrode for a lithium-ion battery, comprising a resin current collector; and an electrode active material layer formed on the resin current collector, and containing coated electrode active material particles in which at least a part of a surface of an electrode active material particle is coated with a coating layer including a polymer compound, wherein the resin current collector has a recess on a principal surface that comes into contact with the electrode active material layer, the relationship between the maximum depth (D) of the recess and the D50 particle size (R) of the electrode active material particles satisfies 1.0R?D?6.5R, and the relationship between the length (S) of the shortest part of the length passing through the center of gravity of the recess and the D50 particle size (R) of the electrode active material particles satisfies 1.5R?S.

Abstract: A lithium ion battery current collector which is used in a lithium ion battery in contact with an electrode active material at one principal surface, characterized in that the current collector is provided with a surface layer on the principal surface in contact with the electrode active material, and an uneven structure is provided on a surface in which the surface layer is in contact with the electrode active material, the uneven structure is any of a plurality of recesses composed of closed figures as seen from above, a network structure, or a pattern of recesses and protrusions, which is provided in an outermost layer of the surface layer, and a depth of the recess is 10 to 45 ?m, a length of a shortest portion of lengths passing through a centroid of the recess is 30 to 105 ?m, and a proportion of an area of the recess as seen from above is 19% to 61% with respect to an area of a surface of the current collector provided with the recess as seen from above.