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Over the past decade, a tremendous amount of research has been conducted on cathode materials for use in lithium 1 and lithium-ion batteries. 2,3 Many different metal oxides and chalcogenides have been explored. In the case of lithium-ion batteries, for which the cathode must supply the lithium to a nonlithiated anode, cathodes based on manganese (LiMn 2 O 4 ), 4 cobalt (LiCoO 2 ), 5 and nickel (LiNiO 2 ), 6 and combinations thereof (LiM 1x M 2 1Ϫx O 2 ), (where M 1 and M 2 are Co, Ni, and/or Mn) 7 are the most common. Vanadiumbased materials are absent due to the difficulty in preparing an environmentally stable lithiated oxide in a one-step process.Vanadium oxides have been the focus of much research for lithium metal batteries. Chemistries based on V 2 O 5 , 8-10 V 6 O 13 , 11-14 and LiV 3 O 8 15,16 have proven to yield viable materials in metallic systems. However, for use in a lithium-ion battery, where the cathode is the source of lithium, these materials are not suitable. If they were lithiated, they would be attractive materials for lithium-ion batteries due to their high-energy storage capabilities. The amount of energy that can be stored in vanadium systems is higher 17 than that of current materials, LiMn 2 O 4 , LiCoO 2 , and LiM 1 1Ϫx M x 2 O 2 , where M 1 and M 2 ϭ Co, Ni, and/or Mn.Lithiation of metal oxides for producing viable cathodes has proven difficult. The most obvious lithiating reagent is butyllithium. Due to its strong reducing ability, butyllithium can easily over reduce the metal oxide, thus destroying the desired lithiated structure. A milder reducing/lithiating reagent, lithium iodide, has been used successfully to lithiate LiMn 2 O 4 to Li 2 Mn 2 O 4 . 18 Li 2 Mn 2 O 4 , a 3 V cathode, decomposes rapidly in moist air; dry conditions are required so the lithiated metal oxide will not decompose. Pistoia et al., reported 16 that Li 1ϩx V 3 O 8 systems are moisture insensitive for very low values of x.Using inherent features of vanadium oxides, we have prepared a lithiated vanadium oxide. When lithiated, it can be used as the cathode material in a lithium-ion battery. In this manuscript, we present a synthetic method for lithiation of a vanadium oxide. Characterization of the parent compound, LiV 3 O 7.9 , and the lithiated vanadium oxide, Li 4 V 3 O 7.9 , are discussed as well as their respective capacities, rate capabilities, energy storage, and long-term cycle abilities. ExperimentalSynthesis.-All materials were used as received. LiV 3 O 7.9 was prepared by first grinding together V 2 O 5 (battery grade, Kerr-McGee Chemical LLC), LiOHиH 2 O (reagent grade, Aldrich Chemical Corporation), and NH 4 CO 2 CH 3 (reagent grade, Aldrich Chemical Corporation) in a 4:3:1 molar ratio, respectively. Then, the mixture was placed in an alumina crucible (Coors Corporation) and heated at 585ЊC in air for 16 h. After cooling, the material was ground and reheated at 585ЊC in air for an additional 16 h. The resulting product was black in color.Reduction (lithiation) of the LiV 3 O 7.9 by Li 2 S (Alfa-Ae...

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The development of high capacity cathode materials for lithium ion batteries has resulted in three materials dominating the market, lithiated manganese, cobalt and nickel oxides and mixtures thereof. In the search for greater energy storage, we have examined a number of vanadium oxides.Comparing the ratio of lithium to metal atom in the three compounds listed above allows for the extraction of one lithium atom per two metal atoms. If the cathode is vanadium based, the number of cycleable lithiums increases to a value closer to 0.75 -1.00.Despite the fact that vanadium oxides operate at lower voltages, a net gain in energy is observed from the use of LixVyOz over the currently available materials. Lithiation of LiV 3 0 7 9 for use in a lithium ion cell is the focus of this paper. Chemical lithiation by reducing lithium salt will be described.

A Vanadium-Based Cathode for Lithium-Ion Batteries. -LiV 3 O 7.9 (I) is prepared from V 2 O 5 , LiOH·H 2 O. and NH 4 COOMe (alumina crucible, 585 • C, 32 h). Reduction of (I) with Li 2 S gives the lithiated vanadium oxide Li 4 V 3 O 7.9 (II) (MeCN, argon or N 2 atmosphere, 4-12 h). The samples are characterized by XRD. The use of compound (II) as cathode material in lithium-ion batteries is proposed. It shows high discharge capacity, is capable of storing large amounts of energy (630 mW/g), and exhibits a long cycle life (greater than 100 deep discharge cycles vs. Li metal). -(CHALONER-GILL, BEN-JAMIN; SHACKLE, DALE R.; ANDERSEN, TERRELL N.; J. Electrochem.