LITHIUM SECONDARY BATTERY

A lithium secondary battery including a positive electrode, a negative electrode comprising a negative electrode current collector, and an electrolyte disposed between the positive electrode and the negative electrode; and a lithium metal layer on the negative electrode current collector in the negative electrode. The electrolyte includes a first electrolyte layer and a second electrolyte disposed on the first electrolyte layer, wherein the first electrolyte layer faces the negative electrode, and the second electrolyte layer faces the positive electrode. The first electrolyte layer has higher ion conductivity than the second electrolyte layer, and wherein the lithium metal layer is formed by migration of lithium ions from the positive electrode after charging.