A method of manufacturing a porous silicon, comprising: bringing a raw material containing a silicate into contact with an alkali earth metal gas; and bringing the raw material, which was brought into contact with the alkali earth metal gas, into contact with an acid.

The present disclosure provides a method for preparing a porous micron-sized silicon ball negative electrode material, including the following steps: performing high-temperature expansion and mechanical ball milling on a layered silicate raw material, and purifying same by hydrochloric acid washing…