A lithium storage cell comprises at least a first electrode comprising an active material wherein Li.sup.+ cations can be inserted, a second electrode and an electrolyte. The active material of the first electrode comprises a linear condensed compound comprising at least two tetrahedra, respectively of AO.sub.4 and A'O.sub.4 type, bonded by a common oxygen atom. A transition metal ion M.sup.2+ with a degree of oxidation of +2 selected from the group consisting of Ni.sup.2+, Co.sup.2+, Mn.sup.2+, Fe.sup.2+ and Ti.sup.2+ is inserted in the linear condensed compound, and the ratio between the number of Li.sup.+ cations able to be inserted in the active material and the number of transition metal ions M.sup.2+ is strictly greater than 1. A and A' are selected from the group consisting of P.sup.5+, Si.sup.4+, Al.sup.3+, S.sup.6+, Ge.sup.4+, B.sup.3+.