We have recently developed a nondestructive method to visualize and quantify Li atom position in real-time using neutrons by a method referred to as neutron depth profiling (NDP).  In situ NDP is an ideal technique for probing Li complex formation, accumulation and transport within the battery material during charge/discharge.  Currently, our work is focused on understanding the effect of an electrochemical event to the materials’ storage properties.  Specifically we report our recent work on the preferential Li nucleation, Li trapping and Li transport in intermetallic materials like Li_xSn_y, Li_xSi_y and Li_xAl_y and intercalating materials like LiNiMnCoO₃.