The Performance of Single‐Phase V 6 O 13 in the Lithium/Polymer Electrolyte Battery

Three different V 6 O 13 ‐ based cathodes have been incorporated into thin‐film polymer electrolyte cells: single‐phase V 6 O 13 , and V 6 O 13 containing 10 molar percent (m/o) VO 2 or V 2 O 5 . In situ x‐ray diffraction (XRD) reveals four phases, identified as Li 0.5 V 6 O 13 , Li 1.5 V 6 O 13 , Li 3 V 6 O 13 , and Li 6 V 6 O 13 . Cells containing single‐phase V 6 O 13 were cycled between 3.0 and 1.8 V at three different rates (1000, 30, and 7(A). Weight analysis and titration data gave Li 6 V 6 O 13 as the final phase. In situ XRD could identify lithium intercalated phases as the same as those obtained from chemical lithiation. Phase‐pure V 6 O 13 batteries exhibited no significant capacity loss during cycling (up to 60 cycles). With VO 2 or V 2 O 5 present, the capacity was lower and the cyclability poor, particularly in the case of V 2 O 5 .