Li metal coated with Li3PO4 film via atomic layer deposition as battery anode

Lithium metal is expected to become one of the most high-energy density anode materials for electronic storage device. However, sharp lithium dendrites and accumulated “dead lithium” cause the consume of electrolyte and the reduction in stability for lithium metal batteries and further lead to serious safety risks in the practical application. To alleviate this problem, we firstly construct a uniform and dense amorphous Li3PO4 thin film with thickness of 10 nm via atomic layer deposition (ALD) coating lithium metal as anode. The as-prepared Li3PO4 thin film improves the cycling life of the symmetrical batteries more than double and successfully resists the shock of high current. The growth of needle-like lithium dendrites are obviously suppressed due to film's amorphous characteristics and higher modulus. The artificial SEI layer mainly homogenizes the lithium ion flux on the electrode surface to achieve the purpose of uniform Li deposition.