A lithium ion battery having desirable safety performance includes a positive electrode having a positive electrode active material layer, a negative electrode having a negative electrode active material layer, a separator between the positive electrode and the negative electrode, and electrolyte. The positive electrode active material layer is provided with a first recess and a positive lead is soldered in the first recess. The negative electrode active material layer is provided with a second recess and a negative lead is soldered in the second recess. Upper and lower surfaces of the positive lead each is formed with a first insulating glue layer. Surface of the positive electrode active material layer corresponding to the second recess is pasted with a second insulating glue layer.