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 . <EOS>