BATTERY ELECTROLE

Abstract

An electrochemical cell comprising an electrode, an electroactive material for sulfur conversion, a solid electrolyte comprising an oxysulfide; a liquid electrolyte; a separator; and a negative electrode.

Description

INTRODUCTION

[0001] The present disclosure relates to electrodes, for example sulfur-containing electrodes, for use in lithium-ion electrochemical cells and methods for their manufacture.

[0002] There is a need for advanced energy storage devices and systems to meet the energy and / or power requirements for a wide variety of products, including automotive products such as start-stop systems (e.g., 12V start-stop systems), battery-assisted systems, hybrid electric vehicles ("HEVs"), and electric vehicles ("EVs"). Typical lithium-ion and lithium-sulfur batteries comprise at least two electrodes and an electrolyte and / or separator. One of the two electrodes serves as the positive electrode, or cathode, and the other electrode serves as the negative electrode, or anode. Each of the electrodes is connected to a current collector (typically a metal, such as copper for the anode and aluminum for the cathode). A separator and / or electrolyte may be disposed between the negative and positive electrodes.The electrolyte is suitable for conducting lithium ions between the electrodes and, like the two electrodes, can be in solid and / or liquid form and / or a mixture of both. In solid-state batteries, which comprise solid-state electrodes and a solid-state electrolyte, the solid-state electrolyte can physically separate the electrodes, eliminating the need for a separate separator.

[0003] Lithium-sulfur batteries may comprise cathodes with sulfur-based electroactive materials, for example elemental sulfur (S) and / or Li2Sx, where 1 ≤ x ≤ 8. Such cathodes often comprise one or more layers of electroactive material, for example a plurality of particles of electroactive material arranged on or near one or more surfaces of a current collector.

[0004] It would be desirable to develop cathodes that enable lower cell impedance, better utilization of the active material, and improved cathode ion transport and kinetics, as well as methods for manufacturing them for an electrochemical cell that can overcome these challenges, e.g., methods and materials that can be easily integrated into common manufacturing processes. SUMMARY

[0005] In one exemplary embodiment, the present disclosure provides an electrochemical cell. The electrochemical cell may include an electrode comprising an electroactive material for sulfur conversion and a solid electrolyte comprising an oxysulfide; a liquid electrolyte; a separator; and a negative electrode.

[0006] In addition to one or more of the features described herein, the solid electrolyte may comprise 75Li2S-20P2S5-5P2O5; and the liquid electrolyte may comprise lithium bis(trifluoromethanesulfonyl)imide salt and triglyme (G3) (Li(G3)TFSI), or lithium bis(trifluoromethanesulfonyl)imide salt and tetraglyme (G4) (Li(G4)TFSI), wherein the molar ratio of salt to solvent is 1:0.8.

[0007] In another exemplary embodiment, the liquid electrolyte may comprise a limited solvating liquid electrolyte.

[0008] In yet another exemplary embodiment, the separator may comprise a porous polymer separator.

[0009] In yet another exemplary embodiment, the electroactive material for sulfur conversion may comprise S, S8, Li2S8, Li2S6, Li2S4, Li2S2, Li2S, Fe2S, or a combination thereof.

[0010] In yet another exemplary embodiment, the solid electrolyte may comprise yLi2S·(100-yx)P2S5·xP2O5, where y is in a range of 70 mol percent to 80 mol percent and x is in a range of 0.5 mol percent to 10 mol percent.

[0011] In yet another exemplary embodiment, the solid electrolyte may be Li 10 MP2S 12 where M is Si, Ge or Sn; Li6PS5Cl; Li 3,25 Ge 0,25 P 0,75 S4; Li4GeS4; a Li2S-P2S5 system; a Li2S-SnS2 system; a Li2S-SiS2 system; a Li2S-GeS2 system; a Li2S-B2S3 system; a Li2S-Ga2S3 system; a Li2S-P2S3 system; a Li2S-Al2S3 system; Li 3,4 Si 0,4 P 0,6 S4; Li 10 GeP2S 11,7 O 0,3; a lithium argyrodite Li6PS5X, where X is Cl, Br, or I; a Li2O-Li2S-P2S5 system; a Li2S-P2S5-P2O5 system; a Li2S-P2S5-GeS2 system; a Li2S-P2S5-LiX system, where X is F, Cl, Br, or I; a Li2S-As2S5-SnS2 system; a Li2S-P2S5-Al2S3 system; a Li2S-LiX-SiS2 system, where X is F, Cl, Br, and I; 0.4LiIl·0.6Li4SnS4 - Li 11 Si2PS 12 ; a Li2O-Li2S-P2S5-P2O5 system; Li 9,54 Si 1,74 P 1,44 S 117 Cl 0,3 ; Li 9,6 P3S 12 ; Li7P3S 11 ; Li9P3S9O3; L 10,35 Ge 1,35 P 1,65 S 12 ; Li 10,35 Si 1,35 P 1,65 S 12 ; Li 9,81 Sn 0,81 P 2.1.9 S 12 : Li 10 (Si 0,5 Ge 0,5 )P2S 12 ; Li 10 (Ge 0,5 Snow 0,5 )P2S 12 ; Li 10 (Si 0,5 Sn 0,5 )P2S 12 ; Li7P 2,9 Mn 0,1 S 10,7 I 0,3 ; Li 3,833 Sn0,833 Ace 0,166 S4; LiI-Li4SnS4; Li4SnS4; Li 10,35 [SN 0,27 Si 1,08 ]P 1,65 S 12 ; or a combination thereof.

[0012] In yet another exemplary embodiment, the liquid electrolyte may comprise a solvated ionic liquid comprising lithium bis(trifluoromethanesulfonyl)imide salt and diglyme (G2) (Li(G2)TFSI), lithium bis(trifluoromethanesulfonyl)imide salt and triglyme (G3) (Li(G3)TFSI), lithium bis(trifluoromethanesulfonyl)imide salt and tetraglyme (G4) (Li(G4)TFSI), lithium bis(fluorosulfonyl)imide salt and diglyme (G2) (Li(G2)FSI), lithium bis(fluorosulfonyl)imide salt and triglyme (G3) (Li(G3)FSI), lithium bis(fluorosulfonyl)imide salt and tetraglyme (G4) (Li(G4)FSI), lithium bis(pentafluoroethanesulfonyl)imide salt and diglyme (G2) ([Li(G2)]BETI), Lithium bis(pentafluoroethanesulfonyl)imide salt and triglyme (G3) ([Li(G3)]BETI), lithium bis(trifluoromethanesulfonyl)imide salt and tetraglyme (G4) ([Li(G4)]BETI), lithium cyano(trifluoromethanesulfonyl)imide salt and diglyme (G2) ([Li(G2)]CTFSI), lithium cyano(trifluoromethanesulfonyl)imide salt and triglyme (G3) ([Li(G3)]CTFSI),Lithium cyano(trifluoromethanesulfonyl)imide salt and tetraglyme (G4) ([Li(G4)]CTFSI), lithium perchlorate salt and diglyme (G2) ([Li(G2)]ClO4), lithium perchlorate salt and triglyme (G3) ([Li(G3)]ClO4), lithium perchlorate salt and tetraglyme (G4) ([Li(G4)]ClO4), lithium tetrafluoroborate salt and diglyme (G2) ([Li(G2)]BF4), lithium tetrafluoroborate salt and triglyme (G3) ([Li(G3)]BF4), lithium tetrafluoroborate salt and tetraglyme (G4) ([Li(G4)]BF4), lithium nitrate salt and diglyme (G2) ([Li(G2)]NO3), lithium nitrate salt and triglyme (G3) ([Li(G3)]NO3), lithium nitrate salt and tetraglyme (G4) ([Li(G4)]NO3), lithium triflate salt and diglyme (G2) ([Li(G2)]OTf), lithium triflate salt and triglyme (G3) ([Li(G3)]OTf), lithium triflate salt and tetraglyme (G4) ([Li(G4)]OTf), lithium trifluoroacetate salt and diglyme (G2) ([Li(G2)]TFA), lithium trifluoroacetate salt and triglyme (G3) ([Li(G3)]TFA), lithium trifluoroacetate salt and tetraglyme (G4) ([Li(G4)]TFA), or a combination thereof.

[0013] In yet another exemplary embodiment, the liquid electrolyte may comprise an ionic liquid electrolyte comprising 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide (EMIM-TFSI), 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide (BMIM-TFSI), N-propyl-N-methylpyrrolidinium bis(trifluoromethanesulfonyl)imide (PYR13TFSI), 1-butyl-1-methylpyrrolidinium bis(trifluoromethylsulfonyl)imide (PYR14TFSI), 1-ethyl-3-methylimidazolium bis(fluorosulfonyl)imide (EMIM-FSI), 1-butyl-3-methylimidazolium bis(fluorosulfonyl)imide (BMIM-FSI), N-propyl-N-methylpyrrolidinium bis(fluorosulfonyl)imide (PYR13-FSI), 1-butyl-1-methylpyrrolidinium bis(fluorosulfonyl)imide (PYR14-FSI) or a combination thereof.

[0014] In yet another exemplary embodiment, the liquid electrolyte may comprise an organic solvent that is ethylene carbonate (EC), propylene carbonate (PC), butylene carbonate (BC), fluoroethylene carbonate (FEC), dimethyl carbonate (DMC), diethyl carbonate (DEC), ethyl methyl carbonate (EMC), methyl formate, methyl acetate, methyl propionate, γ-butyrolactone, γ-valerolactone, 1,1,2,2-tetrafluoroethyl 2,2,3,3-tetrafluoropropyl ether (TTE), bis(2,2,2-trifluoroethyl) carbonate (ETFEC), bis(2,2,2-trifluoroethyl) ether (BTFE), 1,1,2,3,3,3-hexafluoropropyl 2,2,2-trifluoroethyl ether, methyl 3,3,3-trifluoropionate, or ethyl trifluoroacetate, tris(2,2,2-trifluoroethyl)orthoformate (TFEO), Bis(2,2,2-trifluoroethyl)carbonate) (BTC), methyl 2,2,2-trifluoroethyl carbonate (FEMC), 1,2-dimethoxyethane (DME), 1,2-diethoxyethane, ethoxymethoxyethane, tetrahydrofuran, 2-methyltetrahydrofuran, 1,3-dioxolane (DOL), sulfolane, diglyme (G2), triglyme (G3), tetraglyme (G4), or a combination thereof;and a lithium salt comprising lithium hexafluorophosphate (LiPF6), lithium perchlorate (LiClO4), lithium tetrachloroaluminate (LiAlCl4), lithium iodide (LiI1), lithium bromide (LiBr), lithium thiocyanate (LiSCN), lithium tetrafluoroborate (LiBF4), lithium difluorooxalatoborate (LiBF2(C2O4)) (LiODFB), lithium tetraphenylborate (LiB(C6H5)4), lithium bis(oxalate)borate (LiB(C2O4)2) (LiBOB), lithium tetrafluorooxalatophosphate (LiPF4(C2O4)) (LiFOP), lithium nitrate (LiNO3), lithium hexafluoroarsenate (LiAsF6), lithium trifluoromethanesulfonate (LiCF3SO3), lithium bis(trifluoromethanesulfonimide) (LiTFSI) (LiN(CF3SO2)2), lithium fluorosulfonylimide (LiN(FSO2)2) (LiFSI), Lithium fluoroalkyl phosphate (LiFAP) (Li3O4P), or a combination thereof;

[0015] In yet another exemplary embodiment, the electroactive material for sulfur conversion may comprise a sulfur-carbon composite, a Li2S-C composite, sulfurized polyacrylonitrile, or a combination thereof.

[0016] In yet another exemplary embodiment, the electrode may further comprise an electrically conductive material comprising carbon black, graphite, acetylene black, carbon nanotubes, carbon fibers, carbon nanofibers, graphene, graphene nanoplatelets, graphene oxide, nitrogen-doped carbon, metal powder, a liquid metal, a conductive polymer, or a combination thereof.

[0017] In yet another exemplary embodiment, the electrode may further comprise a binder comprising styrene-butadiene rubber (SBR), hydrogenated nitrile rubber (HNBR), poly(vinylidene fluoride) (PVDF), poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP), polytetrafluoroethylene (PTFE), poly(tetrafluoroethylene-co-perfluoro(3-oxa-4-pentenesulfonic acid)) lithium salt, sodium carboxymethylcellulose (CMC), nitrile-butadiene rubber (NBR), styrene-ethylene-butylene-styrene copolymer (SEBS), styrene-butadiene-styrene copolymer (SBS), lithium polyacrylate (LiPAA), sodium polyacrylate (NaPAA), sodium alginate, lithium alginate, ethylene-propylene-diene monomer (EPDM), or a combination thereof.

[0018] In yet another exemplary embodiment, the electrode may comprise, based on the total weight of the electrode, 40 to 70 weight percent of the electroactive material for sulfur conversion, 5 to 30 weight percent of the solid electrolyte, 0.1 to 20 weight percent of the binder, and 0.1 to 30 weight percent of an electrically conductive material.

[0019] In yet another exemplary embodiment, the negative electrode may comprise lithium, graphite, graphene, hard carbon, soft carbon, carbon nanotubes, silicon, silicon-containing alloys, tin-containing alloys, or a combination thereof.

[0020] In one exemplary embodiment, the present disclosure provides an electrochemical cell. The electrochemical cell may include an electrode comprising an electroactive material for sulfur conversion and an oxide solid electrolyte; a liquid electrolyte; a separator; and a negative electrode.

[0021] In addition to one or more of the features described herein, the liquid electrolyte may comprise a limited solvating liquid electrolyte comprising a solvating ionic liquid.

[0022] In another exemplary embodiment, the oxide solid electrolyte may be Li 1-x Al x Ge 2-x (PO4)3 (LAGP) include (with 0 ≤ x ≤ 2), Li7La3Zr2O 12 (LLZO), or Li 1+x Al x Ti 2-x(PO4)3 (LATP) (where 0 ≤ x ≤ 2); and the liquid electrolyte may comprise lithium bis(trifluoromethanesulfonyl)imide salt and triglyme (G3) (Li(G3)TFSI) or lithium bis(trifluoromethanesulfonyl)imide salt and tetraglyme (G4) (Li(G4)TFSI), wherein the molar ratio of salt to solvent is 1:0.8.

[0023] In one exemplary embodiment, the present disclosure provides an electrochemical cell. The electrochemical cell may include an electrode comprising an electroactive material for sulfur conversion and a solid electrolyte comprising a sulfide; a liquid electrolyte; a separator; and a negative electrode.

[0024] In addition to one or more of the features described herein, the liquid electrolyte may comprise a limited solvating liquid electrolyte comprising a solvating ionic liquid.

[0025] The foregoing features and advantages, as well as other features and advantages of the disclosure, will be readily apparent from the following detailed description when taken in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Further features, advantages and details are listed only as examples in the following detailed description, which refers to the drawings in which: Fig. 1 schematically shows a disassembled isometric view of a prismatic battery cell comprising an anode, an electrolytic material, a separator, and a cathode according to the disclosure; Fig. Figure 2 schematically illustrates a cutaway side view of an embodiment of a cathode; Fig. Figure 3 schematically illustrates elements of a process for forming a cathode for a battery cell; Fig. 4 is a graphical illustration illustrating the electrochemical performance of Comparative Example 1; and Fig. Figure 5 is a graphical illustration illustrating the electrochemical performance of Example 1. DETAILED DESCRIPTION

[0027] The following description is merely exemplary and is not intended to limit the present disclosure, its application, or uses. It should be understood that throughout the drawings, corresponding reference characters designate like or corresponding parts and features.

[0028] According to an exemplary embodiment, an electrode for batteries, for example, lithium-sulfur batteries, and methods of forming and using the same are disclosed. Such batteries can be incorporated into energy storage devices, such as rechargeable lithium-ion batteries, which can be used in vehicle or car transport applications (e.g., motorcycles, boats, tractors, buses, camper vans, caravans, and tanks). However, the present technology can also be used in other electrochemical devices, for example (but not limited to) aerospace components, consumer goods, appliances, buildings (e.g., houses, offices, sheds, and warehouses), office equipment, and furniture, as well as in machinery for industrial equipment, agricultural equipment, farm machinery, or heavy machinery.The present disclosure provides a rechargeable lithium-ion battery having lower cell impedance, increased active material utilization, and improved cathode ion transport and kinetics.

[0029] With reference to the drawings, in which like reference numerals correspond to the same or similar components in the individual figures, Fig. 1 schematically illustrates an embodiment of a prismatic-shaped lithium-ion battery cell 10 comprising an electrode pair 15 having a cathode 20, a separator 40, and an anode 30 arranged in a stack and sealed within a flexible pouch 60 containing an electrolytic material 62. In one embodiment of the battery cell, a reference electrode may be disposed between the anode and the cathode. A first, positive battery cell tab 26 and a second, negative battery cell tab 36 protrude from the flexible pouch 60. The terms "anode" and "negative electrode" are therefore used interchangeably. The terms "cathode" and "positive electrode" are therefore used interchangeably. A single electrode pair 15 comprising an assembly of cathode 20, separator 40, and anode 30 is illustrated.It should be noted that multiple electrode pairs 15 may be arranged and electrically connected in the flexible bag 60, depending on the application of the battery cell 10.

[0030] The cathode 20 includes an electroactive sulfur conversion material 22 disposed on a cathode current collector 24, and the cathode current collector 24 may include a foil portion 25 extending from the electroactive sulfur conversion material 22 to form the second battery cell tab 26.

[0031] The anode 30 includes a second electroactive material 32 disposed on an anode current collector 34. The anode current collector 34 may be a metallic substrate having a foil portion 35 extending from the second electroactive material 32 to form the first battery cell tab 36.

[0032] The cathode and anode current collectors 24, 34 may be metallic plate-shaped elements that contact the respective first and second electroactive materials 22, 32 over a significant surface area. The purpose of the cathode and anode current collectors 24, 34 is to exchange free electrons with the respective first and second electroactive materials 22, 32 during discharging and charging.

[0033] The cathode current collector 24 may be a metallic substrate in the form of a planar sheet made of aluminum or an aluminum alloy and having a thickness of, for example, 0.02 millimeters (mm). The separator 40 is disposed between the cathode 20 and the anode 30 to physically separate and electrically insulate the anode 30 from the cathode 20.

[0034] The anode current collector 34 may be a flat, plate-shaped metallic substrate, which in one embodiment is in the form of a rectangular, planar sheet. In one embodiment, the anode current collector 34 may be arranged as a planar sheet with a non-rectangular shape, a coiled configuration, a cylindrical configuration, or another configuration.

[0035] The anode current collector 34 can be made of one of copper, a copper alloy, stainless steel, nickel, etc., or another material that does not alloy with lithium. In one embodiment, the anode current collector 34 can have a thickness of, for example, 0.02 mm. The second electroactive material 32 is present in a second electroactive material layer, which can be applied to one or both surfaces of the anode current collector 34.

[0036] The cathode current collector 24, the anode current collector 34, or a combination thereof may comprise stainless steel, aluminum, nickel, iron, titanium, copper, tin, a suitable electrically conductive material, or a combination thereof. The cathode current collector 24, the anode current collector 34, or a combination thereof may be, for example, a plated foil in which one side (e.g., the first side or the second side) of the current collector 24, 34 comprises a metal (e.g., first metal) and another side (e.g., the other side of the first side or the second side) of the current collector 24, 34 comprises a different metal (e.g., second metal). The plated foil may comprise, for example, aluminum-copper (AlCu), nickel-copper (NiCu), stainless-steel-copper (SS-Cu), aluminum-nickel (Al-Ni), aluminum-stainless steel (Al-SS), and nickel-stainless steel (Ni-SS). The cathode current collector 24, the anode current collector 34, or a combination thereof may be pre-coated, such as, for example,with graphene or carbon-coated aluminum current collectors. The cathode current collector 24, the anode current collector 34, or a combination thereof may be in the form of a foil, a slotted mesh, a woven mesh, or a combination thereof.

[0037] The electrolytic material 62, which conducts lithium ions, may be contained in the separator 40 and may be exposed at both the cathode 20 and the anode 30 to allow lithium ions to move between the cathode 20 and the anode 30. Lithium ions may be stripped from the anode 30 during discharge or, during charge, may release electrons from the cathode 20, which flow through the current collectors 34 and 24, respectively, via an external circuit connected to either a load or a charger, to the opposing current collectors (24 and 34) and electrodes (20 and 30), where they reduce lithium ions during their intercalation.

[0038] The cathode 20 and the anode 30 are each fabricated as electrode materials capable of depositing and stripping lithium ions (in the case of an anode) or intercalating and de-intercalating (in the case of a cathode). The electrode materials of the cathode 20 and the anode 30 are formulated to store lithium at different electrochemical potentials relative to a common reference electrode (e.g., lithium). In the construction of the electrode pair 15, the anode 30 stores deposited or plated lithium at a lower electrochemical potential (i.e., a higher energy state) than the cathode 20, such that an electrochemical potential difference exists between the cathode 20 and the anode 30 when the anode 30 is lithiated.The electrochemical potential difference for each battery cell 10 can result in a charging voltage in the range of 3 V to 5 V and a nominal open-circuit voltage in the range of 2.9 V to 4.2 V, which can enable the reversible transfer of lithium ions between the cathode 20 and the anode 30 either spontaneously (discharge phase) or by applying an external voltage (charge phase) during operational cycling. The thickness of the anode 30 is between 10 µm and 20 µm in one embodiment.

[0039] Disclosed are a positive electrode including an electroactive material for sulfur conversion and a solid electrolyte, and an electrochemical cell comprising the electrode and a limited-solvating liquid electrolyte. The liquid electrolyte may be a limited-solvating liquid electrolyte that can help prevent sulfur dissolution, and the sulfur reaction may be catalyzed by incorporating the solid electrolyte into the electrode.

[0040] As used herein, the term electroactive conversion material refers to a crystalline structure of the cathode that changes when the electroactive material Li +Bonds can be broken and new compounds can be formed. An example of such a material is Li2S. In contrast, the crystalline structure of an intercalated electroactive material, also known as an intercalated electroactive material, does not change when the electroactive material Li + An example of such a material is nickel-cobalt-manganese (NCM).

[0041] As used herein, the term "limited solvating liquid electrolyte" refers to an electrolyte that does not dissolve a sulfur cathode. An example of a limited solvating liquid electrolyte is Li[G3]TFSI or Li[G4] 0,8 TFSI. In contrast, the term "strongly solvating electrolyte" refers to an electrolyte that can dissolve a sulfur cathode, such as 1 molar (moles per liter, M) LiTFSI in DME:DOL.

[0042] The first electroactive material layer 23 of the cathode 20 may comprise an electroactive material 22 for sulfur conversion, a solid electrolyte comprising an oxide, a sulfide, or an oxysulfide 28, and a first binder 29. The cathode may comprise, based on the total weight of the cathode, 30 wt.% to 70 wt.%, for example, 40 wt.% to 70 wt.%, of the electroactive material for sulfur conversion, 5 wt.% to 50 wt.%, for example, 5 wt.% to 30 wt.%, of the solid electrolyte, 0.1 wt.% to 30 wt.%, for example, 0.1 wt.% to 20 wt.%, of a first electrically conductive material, and 0.1 wt.% to 20 wt.% of a first binder.

[0043] The disclosed solid-state electrolyte of the electrode, in conjunction with the electroactive sulfur conversion material, forms a stationary (e.g., "bonded") or immobile part of a solid structure of the cathode. The first binder can structurally reinforce the electroactive sulfur conversion material and the solid-state electrolyte. An electrolytic material, which may be present within the pores of the cathode, as further described herein, is not a static feature of the cathode. The electrode can have a porosity of 10 to 60%.

[0044] The cathode may be in the form of a layer with a thickness of 1 µm to 1,000 µm, for example, 5 µm to 400 µm or 10 µm to 300 µm. The cathode may be defined by a plurality of electroactive sulfur conversion materials, including, for example, the electroactive sulfur conversion material. The electroactive sulfur conversion material may have an average particle diameter of 0.01 µm to 50 µm, for example, 1 µm to 20 µm.

[0045] The electroactive sulfur conversion material 22 may be, for example, S, S8, Li2S8, Li2S6, Li2S4, Li2S2, Li2S, Fe2S, or a combination thereof. The electroactive sulfur conversion material may comprise a sulfur-carbon composite (e.g., a carbon-loaded electroactive sulfur conversion material), a Li2S-C composite, sulfurized polyacrylonitrile, or a combination thereof. The electroactive sulfur conversion material should undergo sufficient lithiation and delithiation while acting as the positive terminal of the battery cell.

[0046] The electroactive material for sulfur conversion can be present in the cathode in an amount greater than or equal to 50 wt. %, greater than or equal to 60 wt. %, greater than or equal to 70 wt. %, greater than or equal to 80 wt. %, greater than or equal to 90 wt. %, greater than or equal to 95 wt. %, based on the total weight of the cathode; or from 50 wt. % to 99 wt. %, 70 wt. % to 99 wt. %, or 90 wt. % to 99 wt. %, based on the total weight of the cathode. For example, the first electroactive material can comprise a sulfur-carbon composite in an amount of 50 wt. % to 95 wt. %, based on the total weight of the cathode, and the weight ratio of sulfur to carbon in the sulfur-carbon composite can be 1:1 to 9:1.

[0047] The solid electrolyte 28 may comprise yLi2S·(100yx)P2S5·xP205, where y is in a range of 70 mol percent to 80 mol percent and x is in a range of 0.5 mol percent to 10 mol percent. The solid electrolyte 28 may comprise Li 10 MP2S 12 , where M is Si, Ge or Sn; Li6PS5Cl; Li 3,25 Ge 0,25 P 0,75 S4; Li4GeS4; a Li2S-P2S5 system; a Li2S-SnS2 system; a Li2S-SiS2 system; a Li2S-GeS2 system; a Li2S-B2S3 system; a Li2S-Ga2S3 system; a Li2S-P2S3 system; a Li2S-Al2S3 system; Li 3,4 Si 0,4 P 0,6 S4; Li 10 GeP2S 11,7 O 0,3 ; a lithium argyrodite Li6PS S X, where X is Cl, Br, or I; a Li2O-Li2S-P2S5 system; a Li2S-P2S5-P2O5 system; a Li2S-P2S5-GeS2 system; a Li2S-P2S5-LiX system, where X is F, Cl, Br, or I; a Li2S-As2S 5- SnS2 system; a Li2S-P2S5-Al2S3 system; a Li2S-LiX-SiS2 system, where X is F, Cl, Br, and I; 0.4LiI·0.6Li4SnS4; Li 11Si2PS 12 ; a Li2O-Li2S-P2S5-P2O5 system; Li 9,54 Si 1,74 P 1,44 S 11,7 Cl 0,3 ; Li 9,6 P3S 12 ; Li7P3S 11 ; Li9P3S9O3; L 10,35 Ge 1,35 P 1,65 S 12 ; Li 10,35 S 1,35 P 1,65 S 12 ; Li 9,81 Sn 0,81 P 2.1.9 S 12 ; Li 10 (Si 0,5 Ge 0,5 )P2S 12 ; Li 10 (Ge 0,5 Snow 0,5 )P2S 12 ; Li 10 (Si 0,5 Sn 0,5 )P2S 12 ; Li7P 2,9 Mn 0,1 S 10,7 I 0,3 ; Li 3,833 Sn 0,833 Ace 0,166 S4; LiI-Li4SnS4; Li4SnS4; Li 10,35 [Sn 0,27 Si 1,08 ]P 1,65 S 12 ; or a combination thereof.

[0048] The limited solvating liquid electrolyte may comprise a solvating ionic liquid, for example lithium bis(trifluoromethanesulfonyl)imide salt and diglyme (G2) (Li(G2)TFSI), lithium bis(trifluoromethanesulfonyl)imide salt and triglyme (G3) (Li(G3)TFSI), lithium bis(trifluoromethanesulfonyl)imide salt and tetraglyme (G4) (Li(G4)TFSI), lithium bis(fluorosulfonyl)imide salt and diglyme (G2) (Li(G2)FSI), lithium bis(fluorosulfonyl)imide salt and triglyme (G3) (Li(G3)FSI), lithium bis(fluorosulfonyl)imide salt and tetraglyme (G4) (Li(G4)FSI), lithium bis(pentafluoroethanesulfonyl)imide salt and diglyme (G2) ([Li(G2)]BETI), Lithium bis(pentafluoroethanesulfonyl)imide salt and triglyme (G3) ([Li(G3)]BETI), lithium bis(pentafluoroethanesulfonyl)imide salt and tetraglyme (G4) ([Li(G4)]BETI), lithium cyano(trifluoromethanesulfonyl)imide salt and diglyme (G2) ([Li(G2)]CTFSI), lithium cyano(trifluoromethanesulfonyl)imide salt and triglyme (G3) ([Li(G3)]CTFSI),Lithium cyano(trifluoromethanesulfonyl)imide salt and tetraglyme (G4) ([Li(G4)]CTFSI), lithium perchlorate salt and diglyme (G2) ([Li(G2)]ClO4), lithium perchlorate salt and triglyme (G3) ([Li(G3)]ClO4), lithium perchlorate salt and tetraglyme (G4) ([Li(G4)]ClO4), lithium tetrafluoroborate salt and diglyme (G2) ([Li(G2)]BF4), lithium tetrafluoroborate salt and triglyme (G3) ([Li(G3)]BF4), lithium tetrafluoroborate salt and tetraglyme (G4) ([Li(G4)]BF4), lithium nitrate salt and diglyme (G2) ([Li(G2)]NO3), lithium nitrate salt and triglyme (G3) ([Li(G3)]NO3), lithium nitrate salt and tetraglyme (G4) ([Li(G4)]NO3), lithium triflate salt and diglyme (G2) ([Li(G2)]OTf), lithium triflate salt and triglyme (G3) ([Li(G3)]OTf), lithium triflate salt and tetraglyme (G4) ([Li(G4)]OTf), lithium trifluoroacetate salt and diglyme (G2) ([Li(G2)]TFA), lithium trifluoroacetate salt and triglyme (G3) ([Li(G3)]TFA), lithium trifluoroacetate salt and tetraglyme (G4) ([Li(G4)]TFA) or a combination thereof.

[0049] The liquid electrolyte may comprise a lithium salt and an ionic liquid comprising 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide (EMIM-TFSI), 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide (BMIM-TFSI), N-propyl-N-methylpyrrolidinium bis(trifluoromethanesulfonyl)imide (PYR13TFSI), 1-butyl-1-methylpyrrolidinium bis(trifluoromethylsulfonyl)imide (PYR14TFSI), 1-ethyl-3-methylimidazolium bis(fluorosulfonyl)imide (EMIM-FSI), 1-butyl-3-methylimidazolium bis(fluorosulfonyl)imide (BMIM-FSI), N-propyl-N-methylpyrrolidinium bis(fluorosulfonyl)imide (PYR13-FSI), 1-Butyl-1-methylpyrrolidinium bis(fluorosulfonyl)imide (PYR14-FSI) or a combination thereof.

[0050] The liquid electrolyte may comprise an organic solvent including ethylene carbonate (EC), propylene carbonate (PC), butylene carbonate (BC), fluoroethylene carbonate (FEC), dimethyl carbonate (DMC), diethyl carbonate (DEC), ethyl methyl carbonate (EMC), methyl formate, methyl acetate, methyl propionate, γ-butyrolactone, γ-valerolactone, 1,1,2,2-tetrafluoroethyl 2,2,3,3-tetrafluoropropyl ether (TTE), bis(2,2,2-trifluoroethyl) carbonate (ETFEC), bis(2,2,2-trifluoroethyl) ether (BTFE), 1,1,2,3,3,3-hexafluoropropyl 2,2,2-trifluoroethyl ether, methyl 3,3,3-trifluoropionate or ethyl trifluoroacetate, tris(2,2,2-trifluoroethyl)orthoformate (TFEO), Bis(2,2,2-trifluoroethyl)carbonate) (BTC), methyl 2,2,2-trifluoroethyl carbonate (FEMC), 1,2-dimethoxyethane (DME), 1-2-diethoxyethane, ethoxymethoxyethane, tetrahydrofuran, 2-methyltetrahydrofuran, 1,3-dioxolane (DOL), sulfolane, diglyme (G2), triglyme (G3), tetraglyme (G4), or a combination thereof;and a lithium salt comprising lithium hexafluorophosphate (LiPF6), lithium perchlorate (LiClO4), lithium tetrachloroaluminate (LiAlCl4), lithium iodide (LiI1), lithium bromide (LiBr), lithium thiocyanate (LiSCN), lithium tetrafluoroborate (LiBF4), lithium difluorooxalatoborate (LiBF2(C2O4)) (LiODFB), lithium tetraphenylborate (LiB(C6H5)4), lithium bis(oxalate)borate (LiB(C2O4)2) (LiBOB), lithium tetrafluorooxalatophosphate (LiPF4(C2O4)) (LiFOP), lithium nitrate (LiNO3), lithium hexafluoroarsenate (LiAsF6), lithium trifluoromethanesulfonate (LiCF3SO3), lithium bis(trifluoromethanesulfonimide) (LiTFSI) (LiN(CF3SO2)2), lithium fluorosulfonylimide (LiN(FSO2)2) (LiFSI), Lithium fluoroalkyl phosphate (LiFAP) (Li3O4P), or a combination thereof.;

[0051] The cathode 20 may include a first electrically conductive material. For example, the electroactive material 22 for sulfur conversion may be mixed with the first electrically conductive material that provides an electron conduction path. The first electrically conductive material may be present in the cathode 20 in an amount of 1 wt% to 20 wt%, 1 wt% to 15 wt%, or 1 wt% to 10 wt%, based on the total weight of the cathode 20. The inclusion of the disclosed solid electrolyte may reduce the amount of first electrically conductive material that might otherwise be included in the cathode.

[0052] Examples of the first electrically conductive material include, for example, carbon black (such as Super P), graphite, acetylene black (such as KETCHEN™ Black or DENKA™ Black), carbon nanotubes, carbon fibers, carbon nanofibers, graphene, graphene nanoplatelets, graphene oxide, nitrogen-doped carbon, metal powder (e.g., copper, nickel, steel, or iron), a liquid metal (e.g., Ga, GaInSn), a conductive polymer (e.g., includes polyaniline, polythiophene, polyacetylene, polypyrrole, and the like), or a combination thereof. As used herein, the term "graphene nanoplatelet" refers to a nanoplatelet or a stack of graphene layers. Such an electrically conductive material in particulate form may have a spherical geometry or an axial geometry.

[0053] The term "axial geometry" refers to particles that generally have a rod-like, fibrous, or otherwise cylindrical shape with a clear long or elongated axis. An aspect ratio (AR) for cylindrical shapes (e.g., fiber or rod) can be defined as AR = L:D, where L is the length of the longest axis and D is the diameter of the cylinder or fiber. Exemplary axial geometry electroactive material particles suitable for use in the present disclosure can have a high aspect ratio, ranging, for example, from 10 to 5,000. The axial geometry electroactive material particles for sulfur conversion include fibers, wires, flakes, thread crystals, filaments, tubes, rods, and the like. The term "round geometry" typically refers to particles with a lower aspect ratio, e.g., an aspect ratio closer to 1 (e.g.,less than 10). It should be noted that particle geometry may deviate from a truly round shape and include, for example, elongated or oval shapes, including oblate or flattened spheroids, agglomerated particles, polygonal (e.g., hexagonal) particles, or other shapes that generally have a low aspect ratio. Oblate spheroids may be disc-shaped and have a relatively high aspect ratio. Thus, a generally round particle geometry is not limited to relatively low aspect ratios and spherical shapes.

[0054] The electroactive sulfur conversion material 22 may be mixed with a first binder 29 that improves the structural integrity of the cathode 20. The first binder 29 may be present in the cathode 20 in an amount of 1 wt% to 20 wt%, 1 wt% to 15 wt%, or 1 wt% to 10 wt%, based on the total weight of the cathode 20.

[0055] The binder may comprise styrene-butadiene rubber (SBR), hydrogenated nitrile rubber (HNBR), poly(vinylidene fluoride) (PVDF), poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP), polytetrafluoroethylene (PTFE), poly(tetrafluoroethylene-co-perfluoro(3-oxa-4-pentenesulfonic acid)) lithium salt, sodium carboxymethylcellulose (CMC), nitrile-butadiene rubber (NBR), styrene-ethylene-butylene-styrene copolymer (SEBS), styrene-butadiene-styrene copolymer (SBS), lithium polyacrylate (LiPAA), sodium polyacrylate (NaPAA), sodium alginate, lithium alginate, ethylene-propylene-diene monomer (EPDM), or a combination thereof.

[0056] Without wishing to be bound by theory, it is believed that by incorporating the disclosed solid-state electrolyte into a sulfur cathode, performance is improved by lowering cell impedance, increasing active material utilization by providing more reaction sites for the sulfur redox reaction, and improving ion transport and cathode kinetics. An electrochemical cell comprising a cathode comprising an electroactive material for sulfur conversion and an electrolytic material comprising a solvated ionic liquid (e.g., a limited solvating electrolyte) may have a desirable specific capacity, for example, 1 to 5 milliampere-hours per square centimeter (mAh / cm 2 ).- The solid-state electrolyte can contribute to improved kinetics and energy density.

[0057] An electrochemical cell comprising a cathode comprising a solid-state electrolyte and an electrolytic material comprising an organic solvent and a lithium salt (e.g., a highly solvating electrolyte) may exhibit desirable properties with a reduced electrolyte-to-sulfur volume ratio of less than 8:1. A reduced amount of such an electrolyte may be desirable.

[0058] Fig. 2 schematically illustrates an embodiment of the cathode 20 comprising the cathode current collector 24 with a first electroactive material layer 23 thereon after a sulfur conversion electroactive material slurry has been dried. In one embodiment, and as shown, the first electroactive material layer 23 may be applied to one side of the cathode current collector 24. The first electroactive material layer 23 may be applied to both sides of the cathode current collector 24. The first electroactive material layer 23 may comprise 30 wt% to 70 wt%, for example, 40 wt% to 70 wt%, of the sulfur conversion electroactive material 22, 5 wt% to 50 wt%, for example, 5 wt% to 30 wt%, of the solid electrolyte, 0.1 wt% to 20 wt% of the first binder, and 0.1 wt% to 30 wt% of the first electrically conductive material.

[0059] In one embodiment, the first electroactive material layer 23 may have a thickness between 30 µm and 300 µm. In one embodiment, the first electroactive material layer 23 may have a thickness between, for example, 35 µm and 150 µm.

[0060] The electroactive material slurry for sulfur conversion comprises a mixture of the electroactive material 22 for sulfur conversion, the solid electrolyte 28, a first binder 29, optionally a first electrically conductive material, and a solvent. The electroactive material 22 for sulfur conversion can have a maximum particle size of 100 µm and a minimum particle size of 100 nm.

[0061] The first binder 29 can serve as a binding agent to bond the electroactive material 22 for sulfur conversion, the solid electrolyte 28, optionally an electrically conductive material, and the cathode current collector 24. The first binder 29 can be in the form of a powder, a resin, or dissolved in a solvent.

[0062] The mixture of the electroactive material 22 for sulfur conversion, the solid electrolyte 28, the first binder 29 forming the first electroactive material layer 23, and the optional first electrically conductive material is formed by mixing to form an electroactive material slurry for sulfur conversion using an organic solvent or water, as described by step S301 of the method 300 of Fig. 3. The electroactive material slurry for sulfur conversion including the first electroactive material layer 23 may be applied (e.g., poured) onto the cathode current collector 24, as by step S302 of process 300 of Fig. 3, and dried to form a cathode.

[0063] The first electroactive material layer 23, in one embodiment, can be applied to the cathode current collector 24 by gravure coating, slot die coating, or dip coating. Slot die coating is a coating technique in which the slurry of electroactive material 22 for sulfur conversion is applied to the substrate of the cathode current collector 24 via a narrow slot positioned near the surface. A major advantage of the slot die coating process is the simple relationship between the thickness of the wet film coating, the flow rate of the solution, and the velocity of the coated substrate relative to the head. Furthermore, extremely uniform films over large areas can be achieved with slot die coating. Slot die coating is one of many processes that can be used to deposit a thin liquid film on the surface of a substrate.One of the main advantages of slot die coating is that it can be easily integrated into scale-up processes that include roll-to-roll coating and sheet-to-sheet coating systems.

[0064] The electroactive material slurry for sulfur conversion comprising the first electroactive material layer 23 may, in one embodiment, be applied to the cathode current collector 24 by immersing the cathode current collector 24 in a bath comprising the electroactive material slurry for sulfur conversion.

[0065] The cathode current collector 24 with the first electroactive material layer 23 applied thereon is subjected to a drying process to bond the first electroactive material layer 23 on the surface of the cathode current collector 24 to form the cathode 20, as shown by step S303 of process 300 of Fig. 3. The drying process may include exposing the cathode current collector 24 with the applied first electroactive material layer 23 to an elevated temperature environment for a period of time to remove the solvent, which may include subjecting the cathode current collector 24 with the applied first electroactive material layer 23 to a calendering process to improve the adhesion of the first electroactive material layer 23 to the surface of the cathode current collector 24. The cathode current collector 24 with the applied first electroactive material layer 23 is exposed to a temperature between 60°C and 150°C for a period of 1 to 60 minutes to dry and remove the solvent after the first electroactive material layer 23 has been bonded to the surface of the cathode current collector 24.

[0066] Accordingly, a wet process for forming the cathode may comprise mixing the electroactive sulfur conversion material, the disclosed solid electrolyte, and the first binder in a solvent to form a slurry; pouring the slurry onto a current collector; and drying the slurry to form the electrode comprising the disclosed solid electrolyte. The solvent may comprise toluene, an alkane, anisole, an organic phosphate, or a combination thereof.

[0067] And a dry process for forming the cathode may include dry mixing the electroactive sulfur conversion material, the disclosed solid electrolyte, and the first binder to form a mixture; coating the mixture onto a current collector to form a coated current collector; and calendering the coated current collector to form the electrode including the disclosed solid electrolyte. The mixing may include dual-blade milling, ball milling, the use of a circulating mixed hybridizer, or a combination thereof. Coating the mixture onto a current collector may include dry coating, dry spraying, hot pressing and melt extrusion, three-dimensional printing, or a combination thereof. The calendering may include a pressure of 20 to 500 megapascals.

[0068] The anode may be in the form of a layer with a thickness of 1 µm to 1,000 µm, for example, from 5 µm to 400 µm or from 10 µm to 300 µm. The anode may be defined by a plurality of second electroactive materials, for example, comprising the second electroactive material. The second electroactive material may have an average particle diameter of 0.01 µm to 50 µm, for example, from 1 µm to 20 µm.

[0069] An electroactive material layer of the anode may comprise a second electroactive material, a second electrically conductive material, and a second binder. The anode may comprise, based on the total weight of the anode, 30 wt.% to 100 wt.% of the second electroactive material, 0 wt.% to 30 wt.% of the second electrically conductive material, 0 wt.% to 20 wt.% of the second binder, and 0 wt.% to 30 wt.% of electrolytic material.

[0070] The anode comprises a second electroactive material as a lithium host material, which can serve as the negative terminal of a lithium-ion battery. The anode may, for example, comprise a lithium host material (e.g., a second electroactive material) that can function as the negative terminal of the battery cell. The anode may be defined by a plurality of particles of the second electroactive material.

[0071] The anode may comprise a second electroactive material comprising lithium, for example, lithium metal, a lithium alloy (such as a lithium-silicon alloy, a lithium-aluminum alloy, a lithium-indium alloy, a lithium-tin alloy, or a combination thereof), or a combination thereof. The anode may further comprise silicon, tin oxide, aluminum, indium, zinc, germanium, silicon oxide, titanium oxide, lithium titanate, iron sulfide (FeS), Li4Ti5O 12, or a combination thereof, e.g., silicon mixed with graphite. The anode can be made of lithium metal itself.

[0072] The second electroactive material may be present in the anode in an amount of 70 wt% to 100 wt%, 70 wt% to 98 wt%, 70 wt% to 95 wt%, 80 wt% to 95 wt%, based on the total weight of the anode.

[0073] The anode may comprise a second electrically conductive material. For example, the second electroactive material may be mixed with the second electrically conductive material that provides an electron conduction path. The second electrically conductive material may be present in the anode in an amount of 0 wt% to 30 wt%, 1 wt% to 25 wt%, 1 wt% to 20 wt%, 1 wt% to 10 wt%, 3 wt% to 20 wt%, or 5 wt% to 15 wt%, based on the total weight of the anode.

[0074] The second electrically conductive material may be the same as the first electrically conductive material or it may be different from it and may include, for example, carbon black (such as Super P), graphite, acetylene black (such as KETCHEN™ Black or DENKA™ Black), carbon nanotubes, carbon fibers, carbon nanofibers, graphene, graphene nanoplatelets, graphene oxide, nitrogen-doped carbon, metal powder (e.g., copper, nickel, steel, or iron), a liquid metal (e.g., Ga, GaInSn), a conductive polymer (e.g., includes polyaniline, polythiophene, polyacetylene, polypyrrole, and the like), or a combination thereof.

[0075] The anode may comprise a second binder. The second electroactive material may, for example, be blended with a second binder that improves the structural integrity of the anode. The second binder may be present in the anode in an amount of 0 wt% to 30 wt%, 1 wt% to 25 wt%, 1 wt% to 20 wt%, 1 wt% to 10 wt%, 3 wt% to 20 wt%, or 5 wt% to 15 wt%, based on the total weight of the anode. The second binder may comprise, for example, PTFE, sodium carboxymethylcellulose (CMC), styrene-butadiene rubber (SBR), poly(vinylidene fluoride) (PVDF), nitrile-butadiene rubber (NBR), styrene-ethylene-butylene-styrene copolymer (SEBS), styrene-butadiene-styrene copolymer (SBS), lithium polyacrylate (LiPAA), sodium polyacrylate (NaPAA), sodium alginate, lithium alginate, ethylene-propylene-diene monomer (EPDM), or a combination thereof.

[0076] The separator may have a thickness between 10 µm and 50 µm. The separator may comprise a porous polymer (e.g., polyolefin) that provides heat resistance. With the disclosed use of an electroactive material for sulfur conversion and a limitedly solvating liquid electrolyte (e.g., an electrolyte that does not dissolve a sulfur cathode), a porous separator may be used.

[0077] Examples of polyolefins include polyethylene (PE) (as well as variants such as high-density polyethylene (HDPE), low-density polyethylene (LDPE), linear low-density polyethylene (LLDPE), and ultra-high molecular weight polyethylene (UHMWPE)), polypropylene (PP), and a blend of PE and PP. The polymer can electrically insulate and physically separate the cathode and anode.

[0078] The separator can be a solid polymer electrolyte material comprising a polymer—such as polyethylene oxide (PEO), polypropylene oxide (PPO), or polyacrylonitrile (PAN)—a solid electrolyte material (e.g., an oxide-based electrolyte material or a sulfide-based electrolyte material), or a gel polymer electrolyte material containing a lithium salt or swollen with a lithium salt solution. The cathode and anode reversibly exchange lithium ions through the separator during applicable discharge and charge cycles.

[0079] The separator may, for example, comprise a microporous polymeric separator comprising a polyolefin or polytetrafluoroethylene (PTFE). The polyolefin may be a homopolymer (derived from a single monomer component) or a heteropolymer (derived from more than one monomer component), which may be either linear or branched. If a heteropolymer is derived from two monomer components, the polyolefin may adopt any copolymer chain arrangement, including that of a block copolymer or a random copolymer. If the polyolefin is a heteropolymer derived from more than two monomer components, it may also be a block copolymer or a random copolymer.The polyolefin can be polyethylene (PE), polypropylene (PP), or a blend of PE and PP, or multilayer structured porous films made of PE, PP, or a combination thereof, for example, a PP-PE two-layer structure or a PP-PE-PP three-layer structure. Commercially available membranes for porous polyolefin separators include CELGARD. ® 2500 (single-layer polypropylene separator) and CELGARD ® 2325 (three-layer polypropylene / polyethylene / polypropylene separator) offered by Celgard LLC.

[0080] If the separator is a microporous polymeric separator, it can be a single layer or a multi-layer laminate, which can be manufactured using either a dry or wet process. For example, in certain cases, a single layer of the polyolefin can form the entire separator. The separator can be a fibrous membrane with an abundance of pores extending between the opposing surfaces and, for example, have an average thickness of less than one millimeter. Several discrete layers of similar or different polyolefins can be combined to form the microporous polymeric separator. In addition to polyolefins, the separator can also comprise polymers, such as:Polyethylene terephthalate (PET), polyvinylidene fluoride (PVDF), a polyamide, polyimide, poly(amide-imide) copolymer, polyetherimide, cellulose, or a combination thereof, or any other suitable material for creating the desired porous structure. The separator may comprise a cellulose separator, a PVDF membrane, and a porous polyimide membrane.

[0081] The separator may comprise a high-temperature-stable polymer, such as polyimide nanofiber-based nonwovens, nano-sized polyethylene membranes coated with Al2O3 and poly(lithium 4-styrenesulfonate), SiO2-coated polyethylene, co-polyimide-coated polyethylene, polyetherimides (PEI), bisphenol acetone diphthalic anhydride (BPADA) and para-phenylenediamine, expanded polytetrafluoroethylene, reinforced polyvinylidene fluoride hexafluoropropylene, and so on. The separator may be a high-temperature-stable separator and comprise a sandwiched PVDF / poly(m-phenyleneisophthalamide) (PMIA) / PVDF nanofiber separator.

[0082] The separator may comprise a ceramic coating, a coating of heat-resistant material, or a combination thereof. The ceramic coating, the coating of heat-resistant material, or a combination thereof may be disposed on one or more sides of the separator. The material forming the ceramic coating may be aluminum oxide (Al2O3), silicon dioxide (SiO2), titanium dioxide (TiO2), or a combination thereof. The heat-resistant material may be, for example, Nomex, aramid, or a combination thereof. The polymer (e.g., polyolefin) may be incorporated into the separator as a fibrous layer to help impart suitable structural and porosity properties to the separator.

[0083] The separator may be infiltrated with a liquid electrolytic material throughout the entire porosity of the polymer. The liquid electrolytic material, which wets both the cathode and the anode, may comprise a lithium salt dissolved in a non-aqueous solvent. The liquid electrolytic material may wet the separator (e.g., fill 5% to 100%, for example, 90%, of its porosity).

[0084] The cathode, anode, and separator may each comprise the electrolytic material, for example, within their pores, capable of conducting lithium ions between the anode and cathode. Any suitable electrolytic material in solid, liquid, or gel form capable of conducting lithium ions between the electrodes may be used in the battery cell. The electrolytic material may, for example, be a non-aqueous liquid electrolyte solution comprising a lithium salt dissolved in an organic solvent or a mixture of organic solvents.

[0085] Suitable lithium salts may contain inert anions. Examples of lithium salts that can be dissolved in an organic solvent or a mixture of organic solvents to form a non-aqueous liquid electrolyte solution include lithium hexafluorophosphate (LiPF6), lithium perchlorate (LiClO4), lithium tetrachloroaluminate (LiAlCl4), lithium iodide (LiI1), lithium bromide (LiBr), lithium thiocyanate (LiSCN), lithium tetrafluoroborate (LiBF4), lithium difluorooxalatoborate (LiBF2(C2O4)) (LiODFB), lithium tetraphenylborate (LiB(C6H5)4), lithium bis(oxalate)borate (LiB(C2O4)2) (LiBOB), lithium tetrafluorooxalatophosphate (LiPF4(C2O4)) (LiFOP), lithium nitrate (LiNO3), lithium hexafluoroarsenate (LiAsF6), lithium trifluoromethanesulfonate (LiCF3SO3), lithium bis(trifluoromethanesulfonimide) (LiTFSI) (LiN(CF3SO2)2), lithium fluorosulfonylimide (LiN(FSO2)2) (LiFSI), lithium fluoroalkyl phosphate (LiFAP) (Li3O4P), or a combination thereof.

[0086] The lithium salt can be dissolved in a variety of organic solvents, for example an alkyl carbonate such as. B. a cyclic carbonate (e.g. ethylene carbonate (EC), propylene carbonate (PC), butylene carbonate (BC), fluoroethylene carbonate (FEC)), a linear carbonate (e.g. dimethyl carbonate (DMC), diethyl carbonate (DEC), ethyl methyl carbonate (EMC)), an aliphatic carboxylic acid ester (e.g. methyl formate, methyl acetate, methyl propionate), a γ-lactone (e.g. γ-butyrolactone, γ-valerolactone), fluorinated ether (e.g. 1,1,2,2-tetrafluoroethyl 2,2,3,3-tetrafluoropropyl ether (TTE), bis(2,2,2-trifluoroethyl) ether (BTFE), tris(2,2,2-trifluoroethyl)orthoformate (TFEO), fluorinated ester (e.g. ethyl 2,2,2-trifluoroethyl carbonate (ETFEC), Bis(2,2,2-trifluoroethyl)carbonate (BTC), methyl 2,2,2-trifluoroethylcarbonate (FEMC)), a chain ether (e.g. 1,2-dimethoxyethane (DME), 1-2-diethoxyethane, ethoxymethoxyethane), a cyclic ether (e.g.Tetrahydrofuran, 2-methyltetrahydrofuran, 1,3-dioxolane (DOL)), a sulfur compound (e.g. sulfolane), 1-ethyl-3-methylimidazoliumbis(trifluoromethylsulfonyl)imide (EMIMTFSI), 1-butyl-3-methylimidazoliumbis(trifluoromethylsulfonyl)imide (BMIM-TFSI), N-propyl-N-methylpyrrolidinium bis(trifluoromethanesulfonyl)imide (PYR13TFSI), 1-butyl-1-methylpyrrolidinium bis(trifluoromethylsulfonyl)imide (PYR14TFSI), 1-ethyl-3-methylimidazoliumbis(fluorosulfonyl)imide (EMIM-FSI), 1-Butyl-3-methylimidazolium bis(fluorosulfonyl)imide (BMIM-FSI), N-propyl-N-methylpyrrolidinium bis(fluorosulfonyl)imide (PYR13-FSI), 1-butyl-1-methylpyrrolidinium bis(fluorosulfonyl)imide (PYR14-FSI), or a combination thereof. The electrolytic material may comprise 0.5 moles per liter (molar (M)) to 9.0 M or 0.5 M to 4.0 M of the one or more lithium salts.If the electrolytic material has a lithium concentration greater than 2 M or ionic liquids, the electrolytic material may comprise fluoroethylene carbonate (FEC), hydrofluoroether (HFE), or a combination thereof.

[0087] The electrolytic material, for example, a solid-state electrolyte, can serve as both a lithium-ion conductor and a separator, eliminating the need for a separate separator component. Solid-state electrolyte particles can include oxide-based particles, sulfide-based particles, metal-doped or substituted oxide particles with different valences, inactive oxide particles, nitride-based particles, hydride-based particles, halide-based particles, borate-based particles, or a combination thereof.

[0088] The oxide-based particles may comprise a garnet ceramic, a LISICON-type oxide, a NASICON-type oxide, a perovskite-type ceramic, or a combination thereof. The garnet ceramic may, for example, be Li7La3Zr2O 12 , Li 6.2 Ga 0,3 La 2,95 Rb 0.05 Zr2O 12 , Li 6,85 La 2,9 Ca 0,1 Zr 1,75 Nb 0,25 O 12 , Li 6,25 Al 0.25 La3Zr2O 12 , Li 6,75 La3Zr 1,75 Nb 0.25 O 12 or a combination thereof. The LISICON type oxide can be Li 2+2x Zn 1-x GeO4 (with 0 < x < 1), Li 14 Zn(GeO4)4, Li 3+x (P 1-x Si x )O4 (with 0 < x < 1), Li 3+x Ge x V 1-xO4 (with 0 < x < 1) or a combination thereof. The NASICON-type oxide can be defined by LiMM'(PO4)3, where M and M' are independently Al, Ge, Ti, Sn, Hf, Zr, or La. The NASICON-type oxide can be, for example, Li 1+x Al x Ge 2-x (PO4)3 (LAGP) (with 0 ≤ x ≤ 2), Li 1,4 Al 0.4 Ti 1,6 (PO4)3, Li 1,3 Al 0,3 Ti 1,7 (PO4)3, LiTi2(PO4)3, LiGeTi(PO4)3, LiGe2(PO4)3, LiHf2(PO4)3 or a combination thereof. The perovskite-type ceramic can be Li 3,3 La 0,53 TiO3, LiSr 1,65 Zr 1,3 Ta 1,7 O9, Li 2xy Sr 1x Ta y Zr 1y O3 (with x = 0.75y and 0.60 < y < 0.75), Li 3 / 8 Sr 7 / 16 Nb 3 / 4 Zr 1 / 4 O3, Li 3x La (2 / 3-x) TiO3 (with 0 < x < 0.25) or a combination thereof.

[0089] The metal-doped or substituted oxide particles with different valence can be, for example, aluminum (Al) or niobium (Nb) doped Li7La3Zr2O 12 , antimony (Sb) doped Li7La3Zr2O 12 , gallium (Ga) doped Li7La3Zr2O 12 , LiSn2P3O substituted with chromium (Cr) and / or vanadium (V) 12 , aluminum (Al) substituted Li 1+x+y Al x Ti 2-x Si Y P 3-y O 12 (with 0 < x < 2 and 0 < y < 3) or a combination thereof.

[0090] The sulfide-based particles may comprise, for example, a pseudobinary sulfide, a pseudoternary sulfide, a pseudoquaternary sulfide, or a combination thereof. Exemplary pseudobinary sulfide systems include Li2S-P2S5 systems (such as Li3PS4, Li7P3S 11 , and Li 9,6 P3S 12), Li2S-SnS2 systems (such as Li4SnS4), Li2S-SiS2 systems, Li2S-GeS2 systems, Li2S-B2S3 systems, Li2S-Ga2S3 systems, Li2S-P2S3 systems, Li2S-Al2S3 systems, L 13,4 Si 0,4 P 0,6 S4, Li 10 GeP2S 11,7 O 0,3 , lithium argyrodites Li6PS5X (where X is one of Cl, Br, and I). Exemplary pseudoternary sulfide systems include Li2O-Li2S-P2S5 systems, Li2S-P2S5-P2O5 systems, Li2S-P2S5-GeS2 systems (such as Li 3,25 Ge 0,25 P 0,75 S4 (thio-LISICON) and Li 10 GeP2S 12 (LGPS)), Li2S-P2S5-LiX systems (where X is one of F, Cl, Br and I) (such as Li6PS5Br, Li6PS5Cl, L7P2S8I and Li4PS4I), Li2S-As2S5-SnS2 systems (such as Li 3,833 Sn 0,833 Ace 0,166 S4), Li2S-P2S5-Al2S3 systems, Li2S-LiX-SiS2 systems (where X is one of F, Cl, Br and I), 0.4LiI·0.6Li4SnS4 and Li 11 Si2PS 12 . Exemplary pseudoquaternary sulfide systems include Li2O-Li2S-P2S5-P2O5 systems, Li 9,54 Si1,74 P 1,44 S 11,7 Cl 0,3 , Li 9,6 P3S 12 , Li7P3S 11 , Li9P3S9O3, L 10,35 Ge 1,35 P 1,65 S 12 , L 10,35 Yes 1,35 P 1,65 S 12 , Li 9,81 Sn 0,81 P 2.1.9 s 12 ; Li 10 (If 0,5 Ge 0,5 )P2S 12 , Li 10 (Ge 0,5 Snow 0,5 )P2S 12 , Li 10 (If 0,5 Sn 0,5 )P2S 12 , Li7P 2,9 Mn 0,1 S 10,7 I 0,3 , Li 3,833 Sn 0,833 As 0,166 S4, Li-Li4SnS4, Li4SnS4 and Li 10,35[ Sn 0,27 Yes 1,08] P 1,65 S 12 .

[0091] The inactive oxide particles may, for example, comprise SiO2, Al2O3, TiO2, ZrO2, or a combination thereof; the nitride-based particles may, for example, comprise Li3N, Li7PN4, LiSi2N3, or a combination thereof; the hydride-based particles may, for example, comprise LiBH4, LiBH4-LiX (where X = Cl, Br, or I), LiNH2, Li2NH, LiBH4-LiNH2, Li3AlH6, or a combination thereof; the halide-based particles may, for example, comprise LiI1, Li3InCl6, Li2CdCl4, Li2MgCl4, LiCdI4, Li2ZnI4, Li3OCl, Li3YCl6, Li3YBr6, or a combination thereof; and the borate-based particles may, for example, comprise Li2B4O7, Li2O-B2O3-P2O5, or a combination thereof.

[0092] The descriptions of the cathode, anode, separator, and electrolytic material presented herein are intended as non-limiting examples. Many variations of the chemistry of the individual elements may be applied in the context of the lithium-ion battery cell of the present disclosure. EXAMPLESComparison example 1

[0093] A button cell was fabricated with a cathode made from a slurry containing 60 to 98 wt% of a sulfur-carbon composite (comprising 50 to 95 wt% sulfur and 5 to 50 wt% carbon), 1 to 20 wt% binder, and 1 to 20 wt% electrically conductive material coated with a charge of 1 milligram per square centimeter (mg / cm 2) was cast onto an aluminum current collector. The anode was a lithium metal chip and a polyethylene separator fused with Entek nanoparticles, and lithium bis(trifluoromethanesulfonyl)imide salt and tetraglyme (G4) (Li(G4)TFSI) were used as the electrolyte. Example 1

[0094] A button cell was fabricated with a cathode made from a slurry comprising 80 wt% sulfur in 20 wt% Ketjen black, 70Li2S·25P2S5·5P2O5 solid electrolyte, Super P conductive carbon black, and hydrogenated nitrile rubber (HNBR) binder in a weight ratio of 60:20:10:10, cast with a loading of 1 milligram per square centimeter (mg / cm 2 ) onto an aluminum current collector. The anode was a lithium metal chip and a polyethylene separator fused with Entek nanoparticles. Lithium bis(trifluoromethanesulfonyl)imide salt and tetraglyme (G4) (Li(G4)TFSI) were used as the electrolyte.

[0095] Fig. Figure 4 is a graph of voltage (volts (V)) versus specific capacity (milliampere hours per gram (mAh / g)) for Comparative Example 1 and Fig. Figure 5 is a graph of voltage (V) versus specific capacity (mAh / g) for Example 1, where “1” refers to cycle 1, “5” to cycle 5, “10” to cycle 10, and “20” to cycle 20. The tests included C / 20 in the first cycle and C / 10 in later cycles. As can be seen from the comparison of Fig. 4 with Fig. As can be seen in Figure 5, a higher specific capacity with good cycling stability can be achieved with the disclosed solid electrolyte. The higher plateau of Fig. 4 compared to Fig. 5 means lower impedance and lower overpotential. {Please confirm; include further comments?}

[0096] Without wishing to be bound by theory, it is believed that the disclosed solid-state electrolyte can improve Li-ion conductivity by providing more Li-ion pathways. The disclosed solid-state electrolyte can also provide reaction sites for the S-redox reaction.

[0097] The terms "a" and "an" do not imply a limitation of quantity, but rather denote the presence of at least one of the referenced subject matter. The term "or" means "and / or" unless the context clearly indicates otherwise. References throughout this specification to "an aspect" mean that a particular element (e.g., a feature, structure, step, or property) described in connection with that aspect is included in at least one of the aspects described herein and may or may not be present in other aspects. Furthermore, it is understood that the described elements in the various aspects may be combined in any suitable manner.

[0098] When an element, such as a layer, film, region, or substrate, is described as being "on" another element, it may be directly on top of the other element, or there may be intervening elements. Conversely, when an element is described as being "directly on" another element, there are no intervening elements.

[0099] Unless otherwise indicated herein, all examination standards are the most recent standard in effect on the filing date of this application or, if priority is claimed, the filing date of the earliest priority application in which the examination standard appears.

[0100] Unless otherwise defined, technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs.

[0101] While the above disclosure has been described with reference to exemplary embodiments, it will be appreciated by those skilled in the art that various changes may be made and equivalent elements may be substituted without departing from its scope. Furthermore, many changes may be made to adapt a particular situation or material to the teachings of the disclosure without departing from its essential scope. Therefore, the present disclosure is not intended to be limited to the particular embodiments disclosed, but is intended to include all embodiments falling within its scope.

Claims

[1] Electrochemical cell comprising: an electrode comprising an electroactive material for sulfur conversion and a solid electrolyte comprising an oxysulfide; a liquid electrolyte; a separator; and a negative electrode. [2] An electrochemical cell according to claim 1, wherein: the solid electrolyte comprises 75Li2S-20P2S5-5P2O5; and the liquid electrolyte includes Lithium bis(trifluoromethanesulfonyl)imide salt and triglyme (G3) (Li(G3)TFSI), or Lithium bis(trifluoromethanesulfonyl)imide salt and tetraglyme (G4) (Li(G4)TFSI), where the molar ratio of salt to solvent is 1:0.

8. [3] The electrochemical cell of claim 1, wherein the liquid electrolyte comprises a limited solvating liquid electrolyte. [4] The electrochemical cell of claim 1, wherein the solid electrolyte comprises yLi2S·(100-yx)P2S5·xP2O5, where y is in a range of 70 mol percent to 80 mol percent and x is in a range of 0.5 mol percent to 10 mol percent. [5] Electrochemical cell according to claim 1, wherein the solid electrolyte is Li 10 MP2S 12 , where M is Si, Ge or Sn; Li6PS5Cl; Li 3,25 Ge 0,25 P 0,75 S4; Li4GeS4; a Li2S-P2Ss system; a Li2S-SnS2 system; a Li2S-SiS2 system; a Li2S-GeS2 system; a Li2S-B2S3 system; a Li2S-Ga2S3 system; a Li2S-P2S3 system; a Li2S-Al2S3 system; Li 3,4 Si 0,4 P 0,6 S4; Li 10 GeP2S 11,7 O 0,3 ; a lithium argyrodite Li6PS SX, where X is Cl, Br, or I; a Li2O-Li2S-P2S5 system; a Li2S-P2S5-P2O5 system; a Li2S-P2S5-GeS2 system; a Li2S-P2S5-LiX system, where X is F, Cl, Br, or I; a Li2S-As2S5-SnS2 system; a Li2S-P2S5-Al2S3 system; a Li2S-LiX-SiS2 system, where X is F, Cl, Br, and I; 0.4LiI·0.6Li4SnS4; Li 11 Si2PS 12 ; a Li2O-Li2S-P2S5-P2O5 system; Li 9,54 Si 1,74 P 1,44 S 11,7 Cl 0,3 ; Li 9,6 P3S 12 ; Li7P3S 11 ; Li9P3S9O3; L 10,35 Ge 1,35 P 1,65 S 12 , Li 10,35 Si 1,35 P 1,65 S 12 ; Li 9,81 Sn 0,81 P 2.1.9 s 12 ; Li 10 (Si 0,5 Ge 0,5 )P2S 12 ; Li 10 (Ge 0,5 Snow 0,5 )P2S 12 ; Li 10 (Si 0,5 Sn 0,5 )P2S 12 ; Li7P 2,9 Mn 0,1 S 10,7 I 0,3 ; Li 3,833 Sn 0,833 Ace 0,166S4; LiI-Li4SnS4; Li4SnS4; Li 10,35 [Sn 0,27 Si 1,08 ]P 1,65 S 12 ; or a combination thereof. [6] Electrochemical cell comprising: an electrode comprising an electroactive material for sulfur conversion and an oxide solid electrolyte; a liquid electrolyte; a separator; and a negative electrode. [7] The electrochemical cell of claim 6, wherein the liquid electrolyte comprises a limited solvating liquid electrolyte comprising a solvating ionic liquid. [8] An electrochemical cell according to claim 6, wherein: the oxide solid electrolyte comprises Li 1+x Al x Ge 2-x (PO4)3 (LAGP) (with 0 ≤ x ≤ 2), Li7La3Zr2O 12 (LLZO), or Li 1+x Al x Ti 2-x (PO4)3 (LATP) (with 0 ≤ x ≤ 2); and the liquid electrolyte includes Lithium bis(trifluoromethanesulfonyl)imide salt and triglyme (G3) (Li(G3)TFSI), or Lithium bis(trifluoromethanesulfonyl)imide salt and tetraglyme (G4) (Li(G4)TFSI), where the molar ratio of salt to solvent is 1:0.

8. [9] Electrochemical cell comprising: an electrode comprising an electroactive material for sulfur conversion and a solid electrolyte comprising a sulfide; a liquid electrolyte; a separator; and a negative electrode. [10] The electrochemical cell of claim 9, wherein the liquid electrolyte comprises a limited solvating liquid electrolyte comprising a solvating ionic liquid.

Images