Lithium Titanium Phosphate as Cathode, Anode and Electrolyte for Lithium Rechargeable Batteries
N. V. KOSOVA, D. I. OSINTSEV, N. F. UVAROV and E. T. DEVYATKINA
Institute of Solid State Chemistry and Mechanochemistry,
Siberian Branch of the Russian Academy of Sciences,
Ul. Kutateladze 18, Novosibirsk 630128 (Russia) E-mail: kosova@solid.nsk.su
Pages: 253-260
Abstract
Electrochemical properties and ionic conductivity of LiTi2(PO4)3 (space group R-3c) synthesized using mechanical activation (MA) are investigated. It is established that MA decreases synthesis temperature and time allowing one to obtain the products of more homogeneous phase composition. The cycling ability of the samples is investigated with the help of a galvanostatic set-up in the electrochemical cell LiTi2(PO4)3 (C)/(LiPF6+EK+DMK/Li. It is established that within the potential range 2.0-3.5V the capacity of the samples obtained with the help of MA is higher than that of the ceramic samples by about 20%. Reversible cycling ability of LiTi2(PO4)3, NaTi2(PO4)3 and KTi2(PO4)3 within the range 0.2-1.5V was discovered. It may be due changes in the chemical composition of the electrode as a result of irreversible redox processes participated by PO4 groups. It is shown that the conductivity of LiTi2(PO4)3 and Li1.3Al0.3Ti1.7(PO4)3 obtained using MA is 2-3 orders of magnitude higher than the conductivity of ceramic samples due to a decrease in resistance of the grain boundaries.
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