According to one embodiment, a secondary battery includes a positive electrode, a negative electrode, a nonaqueous electrolyte and a separator. The positive electrode includes a halide including at least one metal element selected from the group consisting of copper, iron, nickel, cobalt, tin, and zinc. The negative electrode includes at least one selected from the group consisting of lithium metal, a lithium alloy, and a compound capable of having Li inserted and extracted. The nonaqueous electrolyte includes an ionic liquid including chlorine ions. The separator has lithium ion conductivity, and is interposed between the positive electrode and the negative electrode.