Intermetallic negative electrodes for non-aqueous lithium cells and batteries

A method of operating an electrochemical cell is disclosed. The cell has an intermetallic negative electrode of Cu6-xMxSn5, wherein x is <=3 and M is one or more metals including Si and a positive electrode containing Li in which Li is shuttled between the positive electrode and the negative electrode during charge and discharge to form a lithiated intermetallic negative electrode during charge. The voltage of the electrochemical cell is controlled during the charge portion of the charge-discharge cycles so that the potential of the lithiated intermetallic negative electrode in the fully charged electrochemical cell is less than 0.2 V but greater than 0 V versus metallic lithium.