Method of preparing cathode containing Iron disulfide for a lithium cell

A primary electrochemical cell comprising a housing;

• a positive and a negative terminal;
• an anode comprising at least one of a lithium metal and lithium alloy;
• a cathode comprising iron disulfide (FeS2), binder material, and conductive carbon, said cell further comprising an electrolyte inserted therein, said electrolyte comprising a lithium salt dissolved in a solvent mixture comprising dioxolane and sulfolane, wherein the cathode is prepared by the method comprising the steps of:
• a) mixing iron disulfide (FeS2) powder, conductive carbon, binder material, and solvent producing a cathode slurry mixture, wherein said binder material comprises a styrene-ethylene/butylene-styrene (SEBS) elastomeric block copolymer and said solvent comprises a hydronaphthalene compound,
• b) coating said cathode slurry onto at least one side of a substrate to produce a wet cathode composite sheet,
• c) passing said wet cathode composite sheet through an oven to evaporate said solvent and produce thereby a dry cathode composite sheeting comprising a dry cathode coating on at least one side of said substrate;
• wherein
• the cell has the discharge property such that when the cell is subjected to a pulsed discharge protocol consisting of a applying a series of pulsed cycles to the cell until a cutoff voltage of 0.9 volts is reached, the number of said pulsed cycles obtained is greater than 650, wherein each of said pulsed cycles consists of applying to said cell both a 1.5 Watt pulse for 2 seconds followed immediately by applying a 0.65 Watt pulse for 28 seconds, wherein said pulsed cycle is repeated consecutively 10 times, followed by resting said cell for 55 minutes, followed by repeating said pulsed cycles 10 times, followed by said resting in continuous cyclic manner until the 0.9 volt cutoff voltage is reached.

A primary electrochemical cell comprising a housing;

• a positive and a negative terminal;
• an anode comprising at least one of a lithium metal and lithium alloy;
• a cathode comprising iron disulfide (FeS2), binder material, and conductive carbon, said cell further comprising an electrolyte inserted therein, said electrolyte comprising a lithium salt dissolved in a solvent mixture comprising dioxolane and sulfolane, said cell having the discharge property that when a pulsed discharge protocol is applied, the resulting ratio Rp is between about 0.08 and 0.15 wherein
• Rp=[P0.9V−P1.05V]/P0.9V
• wherein, P0.9V is the number of pulsed cycles obtained by discharging the cell to a cutoff voltage of 0.9V and P1.05V is the number of pulsed cycles obtained by discharging the cell to a cutoff voltage of 1.05V;
• wherein said pulsed discharge protocol consists of applying a series of pulsed cycles to the cell, wherein each of said pulsed cycles consists of applying to said cell both a 1.5 Watt pulse for 2 seconds followed immediately by applying a 0.65 Watt pulse for 28 seconds, wherein said pulsed cycle is repeated consecutively 10 times, followed by resting said cell for 55 minutes, followed by repeating said pulsed cycles 10 times, followed by said resting in continuous cyclic manner until said 1.05V and 0.9V cutoff voltage is reached, wherein said pulsed discharge protocol is applied to the cell within about 5 years of manufacture of said cell.