Hybrid nano-filament anode compositions for lithium ion batteries

A lithium secondary battery comprising a positive electrode, a negative electrode comprising a hybrid nano-filament composition which is capable of absorbing and desorbing lithium ions, and a non-aqueous electrolyte disposed between said negative electrode and said positive electrode, wherein said hybrid nano-filament composition comprises:

• a) An aggregate of nanometer-scaled, electrically conductive carbon filaments that are interconnected, intersected, or percolated to form a porous, electrically conductive filament network comprising interconnected pores for accommodating said non-aqueous electrolyte, wherein said nanometer-scaled, electrically conductive carbon filaments have an elongate dimension and a first transverse dimension, which is a diameter or a thickness, said first transverse dimension being less than 500 nm and an aspect ratio of said elongate dimension to said first transverse dimension greater than 10, and wherein said nanometer-scaled, electrically conductive carbon filaments are carbonized electro-spun fibers;
• and
• b) Micron- or nanometer-scaled coating that is deposited on a surface of said nanometer-scaled, electrically conductive carbon filaments, wherein said coating deposited on said nanometer-scaled, electrically conductive carbon filaments comprises an negative active material capable of absorbing and desorbing lithium ions and said coating has a thickness less than 20 μm;
• wherein said nanometer-scaled, electrically conductive carbon filaments enable said deposited coating to freely undergo strain relaxation in transverse directions so that said coating does not lose contact with said nanometer-scaled, electrically conductive carbon filaments during charge/discharge cycles of the lithium secondary battery, wherein said coating is wrapped around said nanometer-scaled, electrically conductive carbon filament, wherein said coating deposited on said nanometer-scaled, electrically conductive carbon filaments comprises said negative active material selected from the group consisting of:
• i. germanium (Ge), antimony (Sb), bismuth (Bi), zinc (Zn), aluminum (Al), and cadmium (Cd);
• ii. alloys or intermetallic compounds of Ge, Sb, Bi, Zn, Al, or Cd with other elements, wherein said alloys or compounds are stoichiometric or non-stoichiometric;
• iii. oxides, carbides, nitrides, sulfides, phosphides, selenides, and tellurides of Ge, Sb, Bi, Zn, Al, I or Cd, and their mixtures or composites;
• and
• iv. combinations thereof.