Lithium storage properties of nanocrystalline eta-Cu6Sn5 alloys prepared by ball-milling

Nanocrystalline eta-Cu6Sn5 alloy powders were prepared by high energy ball-milling, Lithium ions can be electrochemically inserted into Cu6Sn5 electrodes, alloying with Sn to form LixSn alloys. Simultaneously, an inactive Cu matrix is produced. which could buffer the volume expansion of the active So due to the formation of Li,Sn alloys. It appears that lithium can react reversibly with the nanocrystalline Cu6Sn5 alloy to some extent. A reversible capacity of similar to 400 mAh/g has been achieved in preliminary tests. The results of ex-situ X-ray diffraction support the above proposal. (C) 2000 Elsevier Science S.A. All rights reserved.