A comparative study is made on the cycle and rate performance of three Fe 2 O 3 -containing electrodes. The first electrode is made from a commercial nanosized ͑Ͻ100 nm͒ Fe 2 O 3 powder, whereas the second is made from a carbon-supported nanosized Fe 2 O 3 ͑Fe 2 O 3 /carbon composite͒. The third electrode is prepared by modifying the second, incorporating the metallic Fe into the Fe 2 O 3 particles ͑Fe 2 O 3 /Fe/carbon composite͒. Three electrodes show the following performance order in the cycle retention and rate capability: nanosized Fe 2 O 3 Ͻ Fe 2 O 3 /carbon composite Ͻ Fe 2 O 3 /Fe/carbon composite. The reverse order is, however, found on both the electrode volume change and the evolution of internal resistance. Thus, the best performance observed with the Fe 2 O 3 /Fe/carbon composite electrode has been ascribed to the presence of a carbon support and metallic Fe, both of which seem to play two important roles: the buffering action against the massive volume change in Fe 2 O 3 particles and providing an electronically conductive network within the swollen electrode layer. © 2010 The Electrochemical Society. ͓DOI: 10.1149/1.3298891͔ All rights reserved. One of the recent issues in lithium-ion batteries ͑LIBs͒ concerns a high energy density, particularly for the rapidly increasing market of sophisticated electronic devices. Transition-metal oxides ͑M x O y , where M is Co, Ni, Fe, etc.͒ have emerged as a potential negative electrode material for high energy density LIBs because they deliver a specific capacity 2-3 times larger than that of the currently used graphite ͑372 mAh g −1 ͒. 1-6 Such a high capacity results from a reduction of metal ions to their elemental state according to the general reaction MO + 2Li + + 2e = Li 2 O + M 0 . As a result of the reduction reaction, nanosized metal particles that are dispersed in the Li 2 O matrix are formed ͑this is called conversion reaction͒, but are restored back to the original oxides by delithiation. The number of electrons involved in this charge-discharge process ͑that is, capacity͒ is thus determined by the oxidation state of metallic components; for instance, six electrons for Fe 2 O 3 . Among the transitionmetal oxides, iron oxide ͑Fe 2 O 3