Could somebody explain in detail, how intercalation process works? For exampe, when Li ion intercalates in graphite where goes external (valent) electron of Li atom? Does it become common with graphite atoms? Is this true that smaller ions easier intercalate into substrate? What`s about protons, which have very small size?Is there some substances which allow to intercalate protons easy? Is this true that Silicon could intercalate more then three Li ions per it`s own atom? How is it possible?