Battery based on organosulfur species
Metal-sulfur batteries, such as lithium-sulfur batteries, are prepared using one or more organosulfur species such as organic polysulfides and organic polythiolates as part of the liquid or gel electrolyte solution, as part of the cathode, and/or as part of a functionalized porous polymer providing an intermediate separator element.
1. A battery, comprising:
a) an anode comprising an anode active material comprising sodium, lithium or an alloy or composite of at least one of sodium or lithium with at least one other metal for providing ions;
b) a cathode comprising a cathode active material comprising elemental sulfur, and optionally elemental selenium or a mixture of elemental chalcogens; and
c) an intermediate separator element positioned between the anode and cathode acting to separate liquid or gel electrolyte solutions in contact with the anode and cathode, through which metal ions and their counterions move between the anode and cathode during charge and discharge cycles of the battery;
wherein the liquid or gel electrolyte solutions comprise a nonaqueous polar aprotic solvent or polymer and a conductive salt and at least one of conditions (i) or (ii) are met:
(i) at least one of the liquid or gel electrolyte solutions additionally comprise at least one organosulfur species;
(ii) the intermediate separator element comprises a functionalized porous polymer containing at least one organosulfur species;
wherein the organosulfur species is selected from the group consisting of an organic polysulfide of formula R 1 —S—S n —R 2 , an organic thiolate of formula R 1 —S-M, and an organic polythiolate of formula R 1 —S—S n -M, wherein R 1 is a C 1 -C 20 organic moiety that may be linear, branched, or cyclic aliphatic or aromatic and that optionally comprises one or more functional groups containing N, O, P, S, Se, Si, Sn, halogen and/or metal, M is lithium, sodium, quaternary ammonium, or quaternary phosphonium, and n is an integer of 1 or more.
2. The battery of claim 1 , wherein the organosulfur species is a dithioacetal or dithioketal of formulas (I) or (II), or a trithio-orthocarboxylate of formula (III):
wherein each R 3 is independently H or a C 1 -C 20 organic moiety that may be linear, branched, or cyclic aliphatic or aromatic and that may optionally comprise one or more functional groups containing N, O, P, S, Se, Si, Sn, halogen and/or metal, o, p and q are each independently an integer of 1 or more, and each Z is independently: a C 1 -C 20 organic moiety that may be linear, branched, or cyclic aliphatic or aromatic and that may optionally comprise one or more functional groups containing N, O, P, S, Se, Si, Sn, halogen and/or metal; Li; Na; quaternary ammonium; or quaternary phosphonium.
3. The battery of claim 1 , wherein the organosulfur species is an aromatic polysulfide of formula (IV), a polyether-polysulfide of formula (V), a polysulfide-acid salt of formula (VI), or a polysulfide-acid salt of formula (VII):
wherein R 4 independently is tert-butyl or tert-amyl, R 5 independently is OH, OLi or ONa, and r is 0 or more in formula (IV) with the aromatic rings being optionally substituted in one or more positions with substituents other than hydrogen, R 6 is a divalent organic moiety in formula (VI), R 5 is a divalent organic moiety in formula (VII), each Z is independently a C 1 -C 20 organic moiety, Li, Na or quaternary ammonium, M is lithium, sodium, quaternary ammonium, or quaternary phosphonium, and o and p are each independently an integer of 1 or more.
4. The battery of claim 1 , wherein the organosulfur species is an organo- or organo-metal polysulfide containing trithiocarbonate functionality of formula (IX), an organo- or organo-metal polysulfide containing dithiocarbonate functionality of formula (X), or an organo- or organo-metal polysulfide containing monothiocarbonate functionality of formula (XI):
wherein Z is a C 1 -C 20 organic moiety, Na, Li, quaternary ammonium or quaternary phosphonium, and o and p are each independently an integer of 1 or more.
5. The battery of claim 1 , wherein the liquid or gel electrolyte solution is additionally comprised of a dimetal polythiolate species of formula M-S—S n -M, wherein each M is independently Li, Na, quaternary ammonium, or quaternary phosphonium, and n is an integer of 1 or more.
6. The battery of claim 1 , wherein the organic moiety contains at least two carbon atoms.
7. The battery of claim 1 , wherein the non-aqueous polar aprotic solvent or polymer contains one or more functional groups selected from ether, carbonyl, ester, carbonate, amino, amido, sulfidyl [—S—], sulfinyl [—S(O)—], or sulfonyl [—SO 2 —].
8. The battery of claim 1 , wherein the conductive salt corresponds to formula MX wherein M is Li, Na or quaternary ammonium and X is (CF 3 SO 2 ) 2 N, CF 3 SO 3 , CH 3 SO 3 , ClO 4 , PF 6 , NO 3 , AsF 6 or halogen.
9. The battery of claim 1 , wherein the organic moiety is oligomeric or polymeric and the organosulfur species comprises at least one —S—S— linkage that is pendant to the backbone of the oligomeric or polymeric organic moiety.
10. The battery of claim 1 , wherein the organic moiety is oligomeric or polymeric and the organosulfur species comprises at least one —S—S— linkage that in incorporated into the backbone of the oligomeric or polymeric organic moiety.