An electrode member of a secondary battery, comprising an insulating substrate, a conducting layer and an active material layer; the conducting layer being provided on a surface of the insulating substrate, and the conducting layer comprising a main portion and a protruding portion extending from the main portion, a direction of the protruding portion which extends from the main portion being defined as an extending direction of the protruding portion, the main portion being coated with the active material layer, the protruding portion being not coated with the active material layer; the active material layer comprising a first portion and a second portion, along the extending direction of the protruding portion, the first portion being positioned at an end of the active material layer away from the protruding portion, the second portion being positioned at a side of the first portion close to the protruding portion and connected with the first portion, and characterized in that a thickness of the first portion is less than a thickness of the second portion, wherein the active material layer further comprises a third portion, the third portion is positioned at a side of the second portion close to the protruding portion and connected with the second portion, and a thickness of the third portion is less than the thickness of the second portion; the thickness of the third portion is gradually decreased along a direction close to the protruding portion; and the electrode member further comprises a protecting layer, the protecting layer is provided at a side of the protruding portion away from the insulating substrate and connected with the third portion. the conducting layer being provided on a surface of the insulating substrate, and the conducting layer comprising a main portion and a protruding portion extending from the main portion, a direction of the protruding portion which extends from the main portion being defined as an extending direction of the protruding portion, the main portion being coated with the active material layer, the protruding portion being not coated with the active material layer; the active material layer comprising a first portion and a second portion, along the extending direction of the protruding portion, the first portion being positioned at an end of the active material layer away from the protruding portion, the second portion being positioned at a side of the first portion close to the protruding portion and connected with the first portion, and characterized in that a thickness of the first portion is less than a thickness of the second portion, wherein the active material layer further comprises a third portion, the third portion is positioned at a side of the second portion close to the protruding portion and connected with the second portion, and a thickness of the third portion is less than the thickness of the second portion; the thickness of the third portion is gradually decreased along a direction close to the protruding portion; and the electrode member further comprises a protecting layer, the protecting layer is provided at a side of the protruding portion away from the insulating substrate and connected with the third portion.