Composite sulphur/carbon conductive material, use as an electrode and method for producing such a material
A method for producing a composite sulphur/carbon conductive material obtained solely from an initial sulphur and an initial carbon which includes the following successive steps between 50% and 90% by weight of initial sulphur and between 50% and 10% by weight of initial carbon having a specific surface smaller than or equal to 200 m 2 /g are placed in a reactor at atmospheric pressure, the sum of the proportions respectively of the initial sulphur and carbon attaining 100%, the reactor is hermetically sealed at atmospheric pressure, and the composite sulphur/carbon conductive material is formed, in powder form, by heat treatment by heating said reactor to a heating temperature comprised between 115° C. and 400° C., without external regulation of the pressure inside the reactor, and keeping said reactor at said heating temperature during a predetermined time.
1. A method for producing a composite sulphur/carbon conductive material obtained from a mixture consisting of an initial sulphur and an initial carbon, comprising the following successive steps:
placing between 50% and 90% weight of initial sulphur and between 50% and 10% weight of initial carbon having a specific surface smaller than or equal to 200 m 2 /g in a reactor at atmospheric pressure, the sum of the proportions respectively of the initial sulphur and carbon attaining 100%,
hermetically sealing the reactor at atmospheric pressure, and
forming the composite sulphur/carbon conductive material, in the form of a powder, by heat treatment by heating said reactor to a heating temperature comprised between 115° C. and 400° C., without external regulation of the pressure inside the reactor, and keeping said reactor at said heating temperature for a predetermined time.
2. The method according to claim 1 , wherein the heating temperature Tc is comprised between 125° C. and 200° C.
3. The method according to claim 1 , wherein the initial carbon is constituted by one or more allotropic forms of carbon.
4. The method according to claim 1 , wherein the initial sulphur is constituted by one or more allotropic forms of sulphur.
5. The method according to claim 4 , wherein the initial sulphur is an α-orthorhombic S 8 sulphur.
6. The method according to claim 1 , wherein the temperature of the reactor returns naturally and progressively to ambient temperature after the heat treatment.
7. The method according to claim 1 , wherein the composite sulphur/carbon conductive material obtained after the heat treatment is then mechanically grinded to obtain a homogeneous grain size distribution.
8. The method according to claim 1 , wherein the heat treatment step is performed in the presence of air.
9. The method according to claim 1 , wherein the specific surface of the initial carbon is smaller than or equal to 65 m 2 /g.