Lithium secondary battery with high energy density

A lithium secondary battery, comprising:

• a positive electrode, a negative electrode, membranes, and electrolyte, wherein the negative electrode is made of a material which can be alloyed with lithium;
• the positive electrode is made of a mix of a transition metal oxide not including lithium and a transition metal oxide including lithium and configured to have an entire reversible lithium storage capacity greater than a lithium capacity dischargeable from the positive electrode;
• and a lithium layer formed on a surface of the negative electrode or positive electrode or both upon initial activation and charging of the lithium secondary battery satisfies the Equation
• S<L<S+I
• where S=a lithium storage capacity of the positive electrode−a capacity of lithium initially included in the positive electrode, L is an amount of lithium within the lithium layer, and I is an initial irreversible consumption capacity in the negative electrode.