Patent ID: 7820324

Claim:
An anode active material, wherein tin (Sn), cobalt (Co), carbon (C), and a fourth element are contained as an element, the carbon content is from 9.9 wt % to 29.7 wt %, and the ratio of cobalt to the total of tin and cobalt is from 30 wt % to 70 wt %, the fourth element is at least one from the group consisting of indium (In), niobium (Nb), germanium (Ge), titanium (Ti), molybdenum (Mo), aluminum (Al), phosphorus (P), and bismuth (Bi), and the content thereof is 14.9 wt % or less, and the coordination number of cobalt as a first neighboring atom around tin obtained by the radial structure function calculated based on one scattering theory of X-ray absorption spectroscopy is 4 or less.