Secondary battery

A secondary battery, comprising:

• an electrode assembly and a housing accommodating the electrode assembly;
• wherein the electrode assembly comprises a first electrode plate, a second electrode plate, and a separator disposed therebetween, the first electrode plate and the second electrode plate are wound to form the electrode assembly;
• the electrode assembly further comprises a tab disposed in the first electrode plate and protrudes from the housing;
• and, an adhesive layer disposed in the tab;
• wherein the adhesive layer comprises:
• a first portion sandwiched between a package area of the housing;
• and,
• a second portion, extending from the first portion along a length direction of the tab, and the second portion is disposed within the housing;
• in a width direction of the tab, the first portion has a width greater than that of the second portion;
• wherein in the length direction of the tab, the second portion protrudes into a space enclosed by an innermost layer of the separator.