LITHIUM SILICATE COMPOUND, POSITIVE ELECTRODE ACTIVE MATERIAL FOR LITHIUM ION SECONDARY BATTERIES, AND LITHIUM ION SECONDARY BATTERY USING SAME

摘要

Provided is a novel lithium silicate material which is useful as a positive electrode material for lithium ion secondary batteries. A lithium silicate compound represented by Li1.5FeSiO4.25. A lithium silicate compound which is composed of lithium (Li), iron (Fe), silicon (Si) and oxygen (O) and is characterized by being represented by the following composition formula: Li1+2deltaFeSiO4+delta-C (wherein -0.25 <= delta <= 0.25 and 0 <= C <= 0.5). Since iron (Fe) can be present in a trivalent form, this lithium silicate compound has more excellent chemical stability in comparison to Li2FeSiO4.