Li[sub x]Cu[sub 6]Sn[sub 5] (0<x<13): An Intermetallic Insertion Electrode for Rechargeable Lithium Batteries

Abstract

It has been discovered that lithium can be inserted into the intermetallic compound in a two‐phase reaction to yield the product . This finding has important implications for designing new intermetallic insertion electrodes (anodes) for rechargeable lithium batteries. The theoretical capacity of derived from the eta‐phase, , with a structure is for , which corresponds to a fully lithiated composition ; this capacity is close to the theoretical capacity of lithiated graphite . The reaction occurs at approximately vs. lithium metal. The best cycling efficiency is obtained when the end voltage is restricted to above the potential of lithium metal. A mechanism is proposed for the insertion of lithium into . ©1999 The Electrochemical Society