Single lithium ion conductor as binder in lithium-sulfur or silicon-sulfur battery

A method of forming a sulfur cathode, the method comprising:

• forming a porous conductive carbonaceous material;
• infiltrating the porous conductive carbonaceous material with molten sulfur that has a crown S8 elemental form and is transitionable to an intermediate polysulfide compound having a structure represented by Li2Sn, wherein 2≦n≦8, via two-electron reduction to form a precursor;
• mixing the precursor with a binder comprising a polymer that is a single-lithium ion conductor formed from a polymeric anion having associated lithium cations to form a slurry;
• and
• slot die coating the slurry onto a current collector to thereby form the sulfur cathode;
• wherein the binder binds together and at least partially encapsulates the porous conductive carbonaceous material and the sulfur to form a physical barrier which at least partially prevents diffusion of the intermediate polysulfide compound from the sulfur cathode;
• wherein mixing includes incorporating the polymeric anion having associated lithium cations with the precursor so that the polymeric anion having associated lithium cations is present in the sulfur cathode in an amount of from about 2 parts by weight to about 40 parts by weight based on 100 parts by weight of the sulfur cathode;
• wherein the polymeric anion having associated lithium cations is a polymer having a polysulfone backbone with pendent lithium bis(trifluoromethanesulfonyl)imide groups.

A battery comprising:

• (a) a sulfur cathode comprising:
• a porous conductive carbonaceous material infiltrated with sulfur that has a crown S8 elemental form and is transitionable to an intermediate polysulfide compound having a structure represented by Li2Sn, wherein 2≦n≦8, via two-electron reduction;
• and
• a binder binding together and at least partially encapsulating the porous conductive carbonaceous material and the sulfur to form a physical barrier which at least partially prevents diffusion of the intermediate polysulfide compound from the sulfur cathode;
• wherein the binder includes a polymer that is a single-lithium ion conductor formed from a polymeric anion having associated lithium cations;
• (b) an anode comprising lithium or a lithium compound;
• (c) a separator disposed between and separating the sulfur cathode and the anode;
• and
• (d) an electrolyte solution contacting the anode and the sulfur cathode and comprising a nonaqueous solution of lithium salts;
• wherein the polymeric anion having associated lithium cations is a polymer having a polysulfone backbone with pendent lithium bis(trifluoromethanesulfonyl)imide groups.