Active substance, nonaqueous electrolyte battery, and battery pack

An active substance comprising:

• particles of niobium titanium composite oxide represented by Ti1-xMxNb2O7 (wherein 0≦x<1 and an element M is at least one selected from the group consisting of Nb, V, Ta, Bi, Sb, As, P, Cr, Mo, W, B, Na, Mg, Al, and Si);
• and
• a phase comprising a carbon material, the phase formed on at least a part of the surface of the particles;
• wherein the carbon material shows, in a Raman chart obtained by Raman spectrometry using a 532-nm measuring light source, a G band observed at from 1530 to 1630 cm−1 and a D band observed at from 1280 to 1380 cm−1 and a ratio IG/ID between a peak intensity IG of the G band and a peak intensity ID of the D band is from 0.8 to 1.2.

A manufacturing method of an active substance comprising:

• providing active material particles comprising niobium and titanium;
• forming a phase which comprises a carbon-containing compound on the surface of the active material particles so as to produce a composite comprising the active material particles and the phase comprising the carbon-containing compound;
• and
• sintering the composite at a temperature of 650° C. or more and less than 900° C. in an inert gas atmosphere.