TECHNOLOGY FOCUS - ELECTRICAL POWER AND ENERGY - Preferred Battery: The lithium ion battery comprises an amount of supplemental lithium corresponding to at least 2.5 (preferably at least 10)% of the negative electrode capacity. In the lithium ion battery, the amount of active materials are balanced such that a reference positive electrode capacity and a reference negative electrode capacity are within 5%of each other, where the reference positive electrode capacity is the sum of any capacity supplied by the supplemental lithium plus the positive electrode capacity evaluated with a lithium foil counter electrode from 4.6V to 2V at a rate of C/20 and the reference negative electrode capacity is evaluated against lithium foil from 0.01-1.5V at a rate of C/20.    TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Material: The composite material comprises (wt.%): pyrolytic carbon (1-40), nanostructured silicon (10-90). Preferred Components: The negative electrode comprises nanostructured silicon or silicon-carbon composite material; silicon, electrically conductive components and polymer binder; silicon based active material, a polymer binder and carbon fiber (2-30 wt.%); or the composite material (m1). The negative electrode has a specific capacity of at least 700 mAh/g at a rate of C/3. The negative electrode further comprises carbon nanofibers, or silicon alloy. The carbon fiber has an average diameter of 25-250 nm, and an average length of 2-25 microns. The negative electrode has an average dry thickness of at least 25 (preferably at least 30) microns. The negative electrode has a density of silicon active material of at least 0.6 g/cm3 and can generate a capacity per unit area of at least 3.5 mAh/cm2. The negative electrode can generate a capacity per unit area of at least 3.5 mAh/cm2. The binder has an elongation of at least 50% without tearing and a tensile strength of at least 100 MPa. The nanostructured silicon comprises nanoparticle silicon or nanoparticle silicon alloy. The nanostructured silicon comprises nanoporous silicon. The pyrolytic carbon is coated onto the nanostructured silicon. The carbon nanofibers or graphitic carbon, and nanostructured silicon are milled to form the composite. The carbon nanofibers or graphitic carbon comprise carbon nanofibers or graphitic carbon. The silicon-based active material comprises nanostructured silicon. The lithium metal oxide is a compound of formula Li1+bNi~aMn~bCo~cA~dO2-zF2.b=0.01-0.3;alpha =0-0.4;beta =0.2-0.65;gamma =0-0.46;delta =0-0.15;z=0-0.2;A=Mg, Sr, Ba, Cd, Zn, Al, Ga, B, Zr, Ti, Ca, Ce, Y, Nb, Cr, Fe, V, and/or Li.Provided that both alpha and gamma are not zero.