NOVELTY - A lithium ion battery (100) comprises an electrode stack containing several positive electrode (104) elements, several negative electrode (102) elements, separator (106) and current collector (108), enclosure, and electrolyte comprising lithium ions. The positive and negative electrode elements comprise electrode structure. The positive electrode comprises active material containing lithium rich metal oxide having density of 2.5-3 g/cc. The negative electrode comprises active material containing silicon based material having density of 0.2-1.5 g/cc.    USE - Lithium ion battery is used for consumer electronics. Uses include but are not limited to power tools, hybrid electric vehicles, cellular phones, lap-top computers, electric vehicles and plug-in hybrid electric vehicles.    ADVANTAGE - The light-weight lithium ion battery has excellent battery performance and durability, and has high energy density and loading levels.    DETAILED DESCRIPTION - A lithium ion battery comprises an electrode stack containing several positive electrode elements, several negative electrode elements, separator material and current collector, enclosure, and electrolyte comprising lithium ions. The separator material separates the adjacent positive and negative electrode elements. The positive and negative electrode elements comprise electrode structure, which is coated on both surfaces of the current collector, and enclosure and an electrolyte comprising lithium ions. The positive electrode comprises active material containing lithium rich metal oxide. The positive electrode active material has specific discharge capacity of 195 mAhour/g or more at C/3 discharged from 4.6-2 V against lithium, loading capacity of 13-35 mg/cm2 on one side of the current collector, and density of 2.5-3 g/cc. The negative electrode comprises active material containing silicon based material. The negative electrode active material has specific discharge capacity of 700 or more mAhour/g at C/3 discharged from 1.5-5 mV against lithium, loading capacity of 2-6 mg/cm2 on one side of the current collector, and density of 0.2-1.5 g/cc. INDEPENDENT CLAIMS are included for the following:    (1) positive electrode, which comprises 90-96 wt.% positive electrode active material, 2-6 wt.% polymeric binder, and 0.5-8 wt.% carbon nanotubes as conductive additive; and    (2) negative electrode, which comprises 60-90 wt.% high capacity negative electrode active material, 8-30 wt.% polymeric binder, and l-15 wt.% conductive additive.    DESCRIPTION OF DRAWING(S) - The drawing shows the schematic view of the electrode stack.    Battery (100)    Negative electrode (102)    Positive electrode (104)    Separator (106)    Current collector (108)