Influence of ion exchange conditions on the defect chemistry and performance of cobalt doped layered lithium manganese oxide based intercalation compounds

It is shown that by varying the conditions used to exchange Na by Li in lay ered sodium manganese oxide based compounds, not only are the guest ions ex changed but the defect chemistry of the host is modified and this has an im portant effect on the reversibility of lithium intercalation; in particular , defect 2.5% Co doped layered lithium manganese oxide exhibits a capacity to store lithium equivalent to 200 mA h g(-1) which fades by only 0.08% per cycle on cycling at 25 mA g(-1).