LITHIUM/SULPHUR ELECTROCHEMICAL CELL

A lithium/sulfur electrochemical element () comprising: a cathode () comprising: i) carbon having a porous structure () comprising pores with a mean diameter less than or equal to 6 nm; ii) sulfur having a degree of oxidation between 0 and −2 in the pores of the carbon; b) an electrolyte comprising: i) at least one organic solvent which is a carbonate; ii) one or more salts, at least one salt being lithium bis(fluorosulfonyl)imide; c) an anode () comprising lithium metal or a metallic alloy of lithium. Such an element provides increased safety of use because it limits the quantity of hydrogen sulfide that can be emitted in the event of an electrolyte leak or in the event of exposure of an electrode of the element to water.