Polymer electrolyte for a lithium sulfur cell

Patent metadata

Field	Value
Publication number	US-2017194633-A1
Application number	US-201515315814-A
Country	US
Kind code	A1
Filing date	May 12, 2015
Priority date	Jun 6, 2014
Publication date	Jul 6, 2017
Grant date	—

Abstract

A polymer or a polymer electrolyte and cathode material for an alkali metal cell, in particular for a lithium-sulfur cell. To improve the performance and reliability of alkali metal cells, for example lithium-sulfur cells, a polymer based on the general chemical formula (I) is provided, where -[A]- stands for a unit which forms a polymer backbone, X stands for a spacer, x stands for the number of spacers X and is 1 or 0, Q stands for a positively charged group Q + and a counterion Z − , or Q stands for a negatively charged group Q − and a counterion Z + , or Q stands for an uncharged group. Moreover, the invention relates to the use thereof, and a cathode, a separator, a protective layer, and a cell.

First claim

1 - 25 . (canceled)

26 . A cathode material for an alkali metal cell or a lithium-sulfur cell, comprising:
at least one cathode active material, the at least one cathode active material including a sulfur-polymer composite; and at least one polymer electrolyte, including at least one repeating unit of the general chemical formula:

where -[A]- stands for a polymer backbone-forming unit,
X stands for a spacer, x stands for the number of spacers X and is 1 or 0, and
Q stands for a positively charged group Q + and a counterion Z, or
Q stands for a negatively charged group Q − and a counterion Z + , or
Q stands for an uncharged group Q.

27 . The cathode material of claim 26 , wherein the cathode material includes a sulfur-polyacrylonitrile composite.

28 . The cathode material of claim 26 , wherein:
Q + stands for a group based on a cation of an ionic liquid and Z − stands for a lithium conducting salt anion, or Q − stands for a group based on a lithium conducting salt anion or a group based on an anion of an ionic liquid, or a sulfonate group or a sulfate group or a carboxylate group or a group based on a phosphoric acid-based anion or a group based on an anion of an imide or a group based on an anion of an amide or a group based on an anion of a carboxylic acid amide, and Z + stands for a lithium ion, and/or Q stands for a cyclic carbonate group or a lactone group or a cyclic carbamate group or an acyclic carbonate group or an acyclic carboxylic acid ester group or an acyclic carbamate group or an alkylene oxide group.

29 . The cathode material of claim 26 , wherein:
Q + stands for a pyridinium group or an ammonium group or an imidazolium group or a piperidinium group or a pyrrolidinium group or a phosphonium group or a guanidinium group or a morpholinium group or a uronium group or a thiouronium group, or Q − stands for a sulfonylimide group or a sulfonate group, in particular Q − stands for a trifluoromethanesulfonylimide group or perfluoroethanesulfonylimide group or fluorosulfonylimide group or a sulfonate group or a trifluoromethanesulfonate group, or Q stands for a cyclic carbonate group or a lactone group or a cyclic carbamate group or an acyclic carbonate group or an acyclic carboxylic acid ester group or an acyclic carbamate group.

30 . The cathode material of claim 26 , wherein:
Q + stands for an ammonium group or a pyridinium group or an imidazolium group, or Q − stands for a benzenesulfonylimide group or a benzenesulfonate group, or Q stands for a cyclic carbonate group or a lactone group or a cyclic carbamate group or an acyclic carbamate group, in particular a cyclic carbonate group or a lactone group or a cyclic carbamate group.

31 . The cathode material of claim 26 , wherein Z − stands for
bis(trifluoromethanesulfonyl)imide and/or bis(perfluoroethanesulfonyl)imide and/or
bis(fluorosulfonyl)imide, in particular bis(trifluoromethanesulfonyl)imide, and/or
trifluoromethanesulfonate and/or tetrafluoroborate and/or bisoxalatoborate and/or
difluorooxalatoborate and/or bromide and/or iodide and/or chloride, in particular Z − stands for bis(trifluoromethanesulfonyl)imide and/or bis(perfluoroethanesulfonyl)imide and/or bis(fluorosulfonyl)imide, in particular bis(trifluoromethanesulfonyl)imide, and/or trifluoromethanesulfonate.

32 . The cathode material of claim 26 , wherein the polymer backbone-forming unit -[A]-includes an alkylene oxide unit and/or a unit which includes a carbonate group, and/or a siloxane unit and/or a phosphazene unit and/or a methyl methacrylate unit and/or a methacrylate unit and/or a phenylene unit and/or a phenylene oxide unit and/or a benzylene unit and/or an alkylene unit, in particular the polymer backbone-forming unit -[A]- including at least one siloxane unit and/or one phosphazene unit and/or one methyl methacrylate unit and/or one methacrylate unit and/or one phenylene unit.

33 . The cathode material of claim 26 , wherein the polymer backbone-forming unit -[A]-includes at least one polyfunctionalized siloxane unit and/or one polyfunctionalized phosphazene unit and/or one polyfunctionalized phenylene unit.

34 . The cathode material of claim 26 , wherein the spacer X includes:
at least one alkylene oxide group, in particular oligoalkylene oxide group, and/or at least one carbonyl group, in particular at least one cyclic carbonate group and/or at least one lactone group and/or at least one cyclic carbamate group and/or at least one acyclic carbonate group and/or at least one acyclic carboxylic acid ester group and/or at least one acyclic carbamate group, in particular at least one acyclic carbonate group, and/or at least one optional further positively charged group Q + , in particular at least one ammonium ion group and/or at least one pyridinium group and/or at least one imidazolium group and/or at least one piperidinium group and/or at least one pyrrolidinium group and/or at least one phosphonium group and/or at least one guanidinium group and/or at least one morpholinium group and/or at least one uronium group and/or at least one thiouronium group, and a counterion Z − , in particular a lithium conducting salt anion, and/or at least one optional further negatively charged group Q − , in particular at least one sulfonylimide group and/or at least one sulfonate group, and a counterion Z + , in particular a lithium ion.

35 . The cathode material of claim 26 , wherein the polymer backbone-forming unit -[A]- and/or the spacer X and/or the group Q or Q + or Q − are/is halogenated, in particular fluorinated.

36 . The cathode material of claim 26 , wherein the polymer backbone-forming unit -[A]- and/or the spacer X and/or the group Q or Q + or Q − includes a fluorinated, in particular perfluorinated, alkylene oxide unit, in particular an oligoalkylene oxide unit, and/or the polymer backbone-forming unit -[A]- and/or the spacer X and/or the group Q or Q + or Q − are/is perfluorinated.

37 . The cathode material of claim 26 , wherein the at least one polymer (P) has or includes at least one repeating unit of the general chemical formula:

where -[A I ]-, -[A II ]-, -[A III ]-, -[A IV ]-, -[A V ]-, -[A VI ]-, -[A VII ]-, -[A VIII ]-, -[A IX ]-, -[A a ]-, -[A b ]-, -[A c ]-, -[A d ]-, -[A e ]-, -[A f ]-, -[A Z ]-, or -[A Z1 ]- stands for a polymer backbone-forming unit, (X I ), (X II ), (X III ), (X IV ), (X V ), (X VI ), (X VII ), (X VIII ), (X IX ), (X a ), (X b ), (X c ), (X d ), (X e ), (X f ), (X Z ), or (X Z1 ) stands for a spacer,
xi, xii, xiii, xiv, xv, xvi, xvii, xviii, xix, xa, xb, xc, xd, xe, xf, xz, or xz1 stands for the number of spacers and is 1 or 0, and
n IV stands for the number of ethylene oxide units and is 1≦n IV ≦15,
n IX stands for the number of ethylene oxide units and is 1≦n IX ≦15,
the polymer backbone-forming unit -[A I ]-, -[A II ]-, -[A III ]-, -[A IV ]-, -[A V ]-, -[A VI ]-, -[A VII ]-, -[A VIII ]-, -[A IX ]-, -[A a ]-, -[A b ]-, -[A c ]-, -[A d ]-, -[A e ]-, -[A f ]-, -[A Z ]-, or -[A Z1 ]- stands for an alkylene oxide unit, in particular an ethylene oxide unit, and/or an alkylene unit and/or a unit which includes a carbonate group, and/or a methacrylate unit and/or a methyl methacrylate unit and/or a siloxane unit and/or a phosphazene unit and/or a phenylene unit, R10, R11, R13, an

Assignees

• Bosch Gmbh Robert

Inventors

• Schumann Bernd
• Thielen Joerg
• Fanous Jean

Classifications

• H01M4/5815 Primary

  Sulfides · CPC title

• H01M2004/028

  Positive electrodes · CPC title

• H01M10/0565

  Polymeric materials, e.g. gel-type or solid-type · CPC title

• H01M4/622

  being polymers · CPC title

• H01M10/052

  Li-accumulators · CPC title