Silicon-containing material and secondary-battery active material including silicon-containing material

A silicon-containing material being obtainable by a production process including a charging/discharging process in a set of two cycles or more wherein cation sorbing and desorbing are carried out to disproportionated silicon monoxide with a constant current and/or at a constant voltage with a C rate of from 1C or more to 4C or less and within a voltage range of from 3.6 V to 4.2 V at a temperature of from 35° C. or more to 80° C. or less, the silicon-containing material including at least:

• a continuous phase including silicon with Si—Si bond, and possessing a bubble-shaped skeleton being continuous three-dimensionally;
• and
• a dispersion phase including silicon with Si—O bond, and involved in an area demarcated by said continuous phase to be in a dispersed state.