Lithium-containing silicon/phosphates, method of preparation, and uses thereof

The invention provides a new electrode active material and cells and batteries which utilize such active material. The active material is represented by the nominal general formula LiaM'(2-b)M"bSicP(3-c)O12, 0 ≤ b ≤ 2, 0 < c < 3. M' and M" are each elements selected from the group consisting of metal and metalloid elements. The value of the variable a depends upon the selection of M' and M" and on the relative proportions designated as b and c.