The

<mml:math display="inline"><mml:mi>ω</mml:mi><mml:mo></mml:mo><mml:msub><mml:mi mathvariant="normal">Li</mml:mi><mml:mrow><mml:mi>x</mml:mi></mml:mrow></mml:msub><mml:msub><mml:mo>V</mml:mo><mml:mrow><mml:mn>2</mml:mn></mml:mrow></mml:msub><mml:msub><mml:mo>O</mml:mo><mml:mrow><mml:mn>5</mml:mn></mml:mrow></mml:msub></mml:math>

ωLixV2O5 phase

<mml:math display="inline"><mml:mo stretchy="false">(</mml:mo><mml:mn>0.4</mml:mn><mml:mo>⩽</mml:mo><mml:mi>x</mml:mi><mml:mo>⩽</mml:mo><mml:mn>3</mml:mn><mml:mo                               stretchy="false">)</mml:mo></mml:math>

(0.4⩽x⩽3) has been investigated as rechargeable cathodic material for lithium batteries. The interest in using the ω phase as rechargeable electrode consists in the stability of its tetragonal structure

<mml:math display="inline"><mml:mo stretchy="false">(</mml:mo><mml:mi mathvariant="normal">Δ</mml:mi><mml:mi>V</mml:mi><mml:mo>/</mml:mo><mml:mi>V</mml:mi><mml:mo><</mml:mo><mml:mn>1</mml:mn><mml:mo>%</mml:mo><mml:mo                               stretchy="false">)</mml:mo></mml:math>

(ΔV/V<1%) as the Li insertion-extraction proceeds. Lithium ions are found to be responsible for the ordering of the structure. AC impedance measurements have shown important kinetic limitations appear in the Li composition range

<mml:math display="inline"><mml:mn>2.2</mml:mn><mml:mo>⩽</mml:mo><mml:mi>x</mml:mi><mml:mo>⩽</mml:mo><mml:mn>3</mml:mn><mml:mo>,</mml:mo></mml:math>

2.2⩽x⩽3, hindering the use of high current densities. However, at C/20 rate a remarkable and stable specific capacity of 310 mAh g⁻¹ is obtained over 30 cycles. Its cycling behavior in the 3.8/1.5 V voltage window has been shown to strongly depend on the C rate and temperature. At a higher rate (C/5), the capacity decline observed as galvanostatic cycling proceeds has been found to originate from a significant dissolution process of the vanadium oxide, leading to the presence of <mml:math display="inline"><mml:msup><mml:mo>V</mml:mo><mml:mrow><mml:mo>IV</mml:mo></mml:mrow></mml:msup></mml:math>VIV and <mml:math display="inline"><mml:msup><mml:mo>V</mml:mo><mml:mrow><mml:mo>III</mml:mo></mml:mrow></mml:msup></mml:math>VIII species in electrolyte. © 2004 The Electrochemical Society. All rights reserved.

Publications with shared reference:

0 publications found