A lithium ion battery comprises a positive electrode, a negative electrode, an electrolyte, and a membrane arranged between the positive electrode and the negative electrode, wherein the positive electrode, the negative electrode and the membrane are immersed in the electrolyte; the membrane comprises a first organic matter layer, a first mixture layer, a substrate, a second mixture layer and a second organic matter layer, which are stacked in sequence; the first organic matter layer and the second organic matter layer are of porous structures, both the first organic matter layer and the second organic matter are made from polyvinylidene difluoride, both the first mixture layer and the second mixture layer are made of a mixture of polyvinylidene difluoride and oxide, and oxide is at least one selected from aluminum oxide, zirconium oxide and titanium dioxide. The lithium ion battery has relatively good cycle performance and safety performance. Besides, the invention further provides a preparation method of the lithium ion battery and a charge method of the lithium ion battery.