Rechargeable battery cell

A rechargeable battery cell having a housing, at least one positive electrode, at least one negative electrode and an electrolyte comprising at least one conducting salt:

• wherein the electrolyte is based on SO2;
• and
• wherein the positive electrode comprises an active material of the composition AxM′yM″z(XO4-mSn);
• A being an alkali metal, an alkaline earth metal, a metal from group 12 of the periodic table or aluminum,
• M′ being at least one metal selected from a group consisting of the elements titanium, vanadium, chromium, manganese, iron, cobalt, nickel, copper and zinc,
• M″ being at least one metal selected from a group consisting of the metals of groups 2, 3, 4, 5, 6, 10, 11, 12, 13, 14, 15 and 16 of the periodic table,
• X being selected from a group consisting of the elements phosphorus and silicon,
• x being greater than 0,
• y being greater than 0,
• z being greater than or equal to 0,
• n being greater than 0 and
• m being at least 0.001 and less than or equal to n.