Polymeric-inorganic hybrid layer for a lithium anode
An lithium-sulfur battery including an anode structure, a cathode, a separator, and an electrolyte is provided. The electrolyte may be dispersed throughout the cathode and in contact with the anode. An artificial solid-electrolyte interphase (A-SEI) may form on the anode, and a protective layer (e.g., that may be pinhole free) may form within and/or on the A-SEI to face the cathode. The protective layer may be formed from carbonaceous materials, which may provide exposed carbon atoms grafted with one or more ions, such as fluorine anions (F−), uniformly dispersed throughout the protective layer. In addition, the protective layer may include polymeric chains positioned generally opposite to each other. The polymeric chains may cross-link upon exposure to ultraviolet (UV) energetic radiation to form a three-dimensional (3D) lattice having a defined cross-linking density suitable to trap one or more anions during discharge-charge operational cycling of the lithium-sulfur battery.
1 . A lithium-sulfur battery comprising:
a cathode;
an anode structure positioned opposite to the cathode, the anode structure comprising:
an anode active material including one or more of a foil of lithium, a coating of lithium, or lithium alloy;
an artificial solid-electrolyte interphase disposed on the anode active material; and
a protective layer disposed at least partially within and on the artificial solid-electrolyte interphase, wherein the protective layer is characterized by a cross-linking density, and includes:
carbonaceous materials including one or more carbon allotropes comprising graphene; and
a first polymeric chain and a second polymeric chain positioned opposite one another and dispersed throughout the carbonaceous materials;
a separator positioned between the anode structure and the cathode; and
an electrolyte dispersed throughout the cathode and in contact with the anode structure, wherein the protective layer is characterized by a glass transition temperature of between 60° C. and 81° C. and forms a cross-linked three-dimensional (3D) polymeric lattice configured to trap at least some TFSI − anions formed by the dissociation of lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) included in the electrolyte, or included in the protective layer, in response to the operational charge/discharge cycling of the lithium-sulfur battery.
2 . The lithium-sulfur battery of claim 1 , wherein the first and second polymeric chains are configured to form carbon-carbon bonds by at least partially cross-linking with each other upon exposure to an ultraviolet (UV) energy, the cross-linked first and second polymeric chains forming the protective layer as a three-dimensional (3D) lattice having a cross-linking density defined by a number of cross-link points per-unit volume and configured to at least partially trap at least some of the TFSI − anions.
3 . The lithium-sulfur battery of claim 2 , wherein the number of cross-link points per-unit volume are configured to restrict re-dissolution of lithium-containing additives in the protective layer toward the electrolyte.
4 . The lithium-sulfur battery of claim 2 , wherein the cross-linking density associated with the protective layer is configured to control swelling between 10%-50% of an original volume of the protective layer by controlling absorption of one or more solvents associated with the electrolyte.
5 . The lithium-sulfur battery of claim 4 , wherein the one or more solvents include dimethoxyethane (DME).
6 . The lithium-sulfur battery of claim 1 , wherein one or more carbon allotropes includes one or more of flat graphene, wrinkled graphene, a plurality of carbon nano-tubes (CNTs), a plurality of carbon nano-onions (CNOs), or non-hollow carbon spherical particles (NHCS).
7 . The lithium-sulfur battery of claim 1 , wherein the protective layer is devoid of pinholes.
8 . The lithium-sulfur battery of claim 1 , wherein the protective layer has a modulus of elasticity between 3 gigapascals (GPa) and 100 GPa.
9 . The lithium-sulfur battery of claim 1 , wherein the dissociation of LiTFSI further produces lithium cations (Li + ), and wherein at least some lithium cations (Li + ) are involved in one or more of a dissociation reaction or a combination reaction during operational charge/discharge cycling of the lithium-sulfur battery.
10 . The lithium-sulfur battery of claim 9 , wherein the combination of fluorine anions (F−) and lithium cations (Li + ) is associated with generation of lithium oxide (Li 2 O), lithium nitrate (LiNO 3 ) or a plurality of nitrogen-oxygen containing compounds.
11 . The lithium-sulfur battery of claim 10 , wherein the three-dimensional scaffold further comprises a plurality of multi-porous pathways formed between adjacent non-hollow carbon spherical particles and within individual non-hollow carbon spherical particles.
12 . The lithium-sulfur battery of claim 10 , wherein one or more of the multi-porous pathways are configured to at least temporarily micro-confine elemental sulfur.
13 . The lithium-sulfur battery of claim 1 , wherein the plurality of fluorinated poly(meth)acrylates comprise a plurality of monomers, one or more monomers including 2,2,3,3,4,4,5,5,6,6,7,7-Dodecafluoroheptyl acrylate (DFHA), 3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10,10-Heptadecafluorodecyl methacrylate (HDFDMA), 2,2,3,3,4,4,5,5-Octafluoropentyl methacrylate (OFPMA), Tetrafluoropropyl methacrylate (TFPM), 3-[3,3,3-Trifluoro-2-hydroxy-2-(trifluoromethyl) propyl]bicyclo[2.2.1]hept-2-yl methacrylate (HFA monomer), or vinyl-based monomers including 2,3,4,5,6-Pentafluorostyrene (PFSt).
14 . The lithium-sulfur battery of claim 1 , wherein the protective layer has a thickness approximately between 0.001 μm and 5 μm.
15 . The lithium-sulfur battery of claim 1 , wherein grafting of at least some of the fluorinated poly(meth)acrylates is initiated by free-radical initiators including one or more of benzoyl peroxide (BPO) or azobisisobutyronitrile (AIBN).
16 . The lithium-sulfur battery of claim 1 , wherein the protective layer includes between approximately 0.001 wt. % to 2 wt. % of the plurality of fluorinated poly(meth)acrylates.
17 . The lithium-sulfur battery of claim 1 , wherein the protective layer further comprises:
an interface layer in contact with the anode; and
a cap layer disposed on top of the interface layer.
18 . The lithium-sulfur battery of claim 17 , wherein the interface layer is formed at contact surfaces between the anode and the protective layer responsive to one or more chemical reactions including a Wurtz reaction.
19 . The lithium-sulfur battery of claim 17 , wherein the interface layer includes one or more of a plurality of cross-linkable monomers including methacrylate (MA), acrylate, vinyl functional groups, or a combination of epoxy and amine functional groups.
20 . The lithium-sulfur battery of claim 17 , wherein the cap layer is characterized by a density gradient associated with one or more self-healing properties to the cap layer.
21 . The lithium-sulfur battery of claim 20 , wherein the density gradient is configured to strengthen the protective layer.
22 . The lithium-sulfur battery of claim 1 , wherein the protective layer further comprises:
between 5 weight percent (wt. %) and 100 wt. % of carbonaceous materials; and
between 95 wt. % and 0 wt. % of fluorinated poly(meth)acrylates.
23 . The lithium-sulfur battery of claim 1 , wherein the jelly roll is formed by winding at least the anode and the cathode together.
24 . The lithium-sulfur battery of claim 1 , wherein the protective layer is associated with a protection of one or more edges of the anode exposed to the electrolyte from lithium erosion.
25 . The lithium-sulfur battery of claim 1 , further comprising an anode current collector coupled to the anode, wherein the protective layer is configured to prevent delamination of lithium from the anode current collector.
26 . The lithium-sulfur battery of claim 1 , wherein the protective layer comprises a carbon-containing electrically-conductive adhesive material that comprises:
a first type of functionalized graphene moiety; and
a second type of functionalized graphene moiety, wherein the first type of functionalized graphene moiety and second type of functionalized graphene moiety are dissimilar relative to each other.
27 . The lithium-sulfur battery of claim 26 , wherein the first type of functionalized graphene moiety and the second type of functionalized graphene moiety are configured to cross-link with each other and form a uniform medium.
28 . The lithium-sulfur battery of claim 27 , wherein the uniform medium is one or more of electrically-conductive or thermally-conductive.
29 . The lithium-sulfur battery of claim 26 , wherein the first type of functionalized graphene moiety and the second type of functionalized graphene moiety are collectively configured to form one or more complementary functional group pairs comprising:
an amine group and an epoxy group;
a thiol group and one or more of a plurality of carbon-carbon double bonds or a plurality of triple bonds;
an amine group and a carboxyl group; or
hydrosilane (—Si—H) and one or more of a plurality of carbon-carbon double bonds or a plurality of triple bonds.
30 . The lithium-sulfur battery of claim 1 , wherein the jelly roll is formed as a cylindrical cell comprising a shell defining an interior volume.
31 . The lithium-sulfur battery of claim 30 , wherein the shell has a diameter between of 18.4 millimeters (mm) and 18.6 mm and a length between 65.1 mm and 65.3 mm.
32 . The lithium-sulfur battery of claim 30 , wherein the shell is congruent with an 18560 cell.
33 . The lithium-sulfur battery of claim 1 , wherein the jelly roll is formed as a prismatic cell comprising a shell defining an interior volume.
34 . The lithium-sulfur battery of claim 33 , wherein the shell has a height between 56 millimeters (mm) and 58 mm, a length between 34 mm and 36 mm, and a width between 6 mm and 8 mm.