A battery includes a shell, a core received in the shell and having first and second electrode tabs, and first and second protection components. Each of the first and second protection components includes two insulating layers and a conducting layer disposed between two insulating layers. The conducting layer of the first protection component defines a first end electrically connected to the first electrode tab and a second end configured as a free end. The conducting layer of the second protection component defines a first end electrically connected to the second electrode tab and a second end configured as a free end.