TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Parameter: No peak attributed to a crystal plane of the solid phase A, is present on a diffraction line obtained by a wide angle X-ray diffraction measurement (X-ray diffraction measurement in a diffraction angle 2 theta of 10-80 degrees, when using copper potassium approximately a radiation as an X-ray source). The solid phase A is a solid phase in a state(s) consisting of amorphous state or a low crystalline state, even after a heat treatment at at least 100 degrees Celsius. It is a solid phase in which a crystallite size of the solid phase A is 5-100 nm, when a heat treatment at at least 100 degrees Celsius is performed. A ratio of the second crystal structure in the solid phase B is 60-95 wt.%. The second crystal structure in the solid phase B contains a crystal structure represented by a space group C and/or space group F, where the space group C and the space group F are space groups in bravais lattice notation. It contains a crystal structure represented by space group Cmcm as annotated by Hermann-Mauguin symbols. A weight ratio of the solid phase A is 5-40 wt.%.Preferred Material: The solid phase A comprises silicon, and the solid phase B comprises titanium and silicon. The solid phase B contains titanium disilicide. EXAMPLE - A mixture of tin and titanium was melted at 1600 degrees Celsius, such that the solid phase A made of tin constituted 20 pbw of the negative electrode material, and the solid phase B made of titanium stannide constituted 80 pbw of the negative electrode material. The melted material was quenched. The obtained solidified material was charged, followed by a mechanical alloying process at a rotation speed of 2800 revolutions/minute. The synthesizing time for the mechanical alloying process was 10 hours.    The resulting negative electrode exhibited initial discharge capacity of 1950 mAh, and a capacity retention rate of 90%, compared with the control using graphite of 1800 mAh, and 89%, respectively.