Black Phosphorus (BP), a layered structure material with good electrical conductance, has been applied in many occasions and it can be synthesized by many methods including ball milling. However, there lacks a clear understanding about the growth mechanisms. In this paper, we adopt three different ball milling techniques (planetary milling, shake milling and plasma-assisted ball milling) to synthesize BP samples and investigate the mechanism of the formation processes. It is found that BP can be successfully synthesized by all these three ball milling techniques and the (020) orientation is preferential during the milling formation processes. And mechanical energy plays an important role in the conversion process of RP to BP by ball milling. The higher mechanical energy could reduce the milling time and improve crystallinity of the synthesized BP. Furthermore, the huge mechanical energy produced in a short time can form a local high energy intensity area, which is beneficial to the phase transition and formation process. The pressure on the sample powders, formed by the impact between balls and between the balls and the vessel wall, is the main influencing factor affecting the transformation process of RP to BP compared with temperature (additional temperature, not the local temperature generated during the milling process). The synthesized BP based composite presents excellent electrochemical performance as lithium ion battery anode material. This work opens new gateway on facile synthesis of BP for various energy applications.