Abstract: A secondary electric cell which includes: a non-aqueous electrolyte, a negative electrode whose active material includes at least one alkali metal in contact with the electrolyte, and a positive electrode whose active material is suitable for intercalating the active material of the negative electrode, wherein said positive electrode includes an active compound or solid solution whose general formula is M.sub.x X, R.sub.y X.sub.3 where:M is an element chosen from lead and tin;R is an element chosen from bismuth and antimony; andX is an element chosen from sulphur and selenium, with x having a value lying between 0 and 1 (inclusive), and y having a value lying between 0 and 2 (inclusive). Such cells may be used in watches or pacemakers.

Abstract: A lithium electric cell. Said electric cell includes a positive electrode (1) and a negative electrode (2) in contact with a liquid electrolyte impregnates in a separator (3). The positive electrode comprising an active compound whose general formula is Li.sub.x Fe.sub.2 S.sub.z with x lying between 0 and 2, and z being not less than 3.