Uv-triggered composite gel films with high solid electrolyte concentrations

Abstract

A battery cell is provided that includes A anode electrodes, C cathode electrodes, and S separators disposed between the A anode electrodes and the C cathode electrodes, where A, C, and S are integers greater than 1. The S separators include a composite gel film that is cured in situ using ultraviolet light and includes a polymer, a solid electrolyte accounting for greater than 20% by weight of the composite gel film, an initiator, and a liquid electrolyte.

Description

Technical Field

[0001] The present disclosure relates to battery cells, and more particularly to battery cells including composite gel films. Background Art

[0002] The information provided in this section is intended to generally introduce the background of the present disclosure. To the extent that work currently named as inventors is described in this section, and with respect to aspects of the specification that may not have otherwise been identified as prior art at the time of filing, no admission is made, either expressly or by implication, that it is prior art with respect to the present disclosure.

[0003] The present disclosure relates to battery cells, and more particularly to battery cells including composite gel films.

[0004] Electric vehicles (EVs), such as battery electric vehicles (BEVs), hybrid vehicles, and / or fuel cell vehicles, include one or more electric motors and a battery system comprising one or more battery cells, modules, and / or battery packs. A power control system is used to control the charging and / or discharging of the battery system during charging and / or driving. Summary of the Invention

[0005] The battery cell includes A anode electrodes, C cathode electrodes, and S separators disposed between the A anode electrodes and the C cathode electrodes, wherein A, C, and S are integers greater than 1. The S separators include a composite gel film that is in-situ cured using ultraviolet light, and the composite gel film includes a polymer, a solid electrolyte that accounts for greater than 20 weight percent of the composite gel film, an initiator, and a liquid electrolyte.

[0006] In other features, the polymer comprises 5 wt % to 30 wt % of the composite gel film, the solid electrolyte comprises 20 wt % to 90 wt % of the composite gel film, the initiator comprises 0.1 wt % to 0.25 wt % of the composite gel film, and the liquid electrolyte comprises 10 wt % to 80 wt % of the composite gel film. Alternatively, the polymer comprises 8 wt % to 15 wt % of the composite gel film, the solid electrolyte comprises 35 wt % to 60 wt % of the composite gel film, the liquid electrolyte comprises 10 wt % to 15 wt % of the composite gel film, and the initiator comprises 0.1 wt % to 0.25 wt % of the composite gel film.

[0007] In other features, the initiator is selected from a Norish type 1 initiator and a Norish type 2 initiator. The liquid electrolyte comprises one or more solvents and one or more lithium salts. The liquid electrolyte further comprises a solid electrolyte interface additive selected from vinylene carbonate (VC), vinyl ethylene carbonate (VEC), butylene carbonate (BC), fluoroethylene carbonate (FEC), 1,3-propane sultone (PS), ethylene sulfite (ES), ethylene sulfate (DTD), and combinations thereof.

[0008] In other features, the one or more lithium salts have a concentration greater than or equal to 0.8 M / L. The one or more solvents are selected from ethylene carbonate (EC), dimethyl carbonate (DMC), gamma-butyrolactone (GBL), propylene carbonate (PC), ethyl methyl carbonate (EMC), diethyl carbonate (DEC), and combinations thereof. The polymer is selected from polyethylene oxide (PEO), polyvinylidene fluoride (PVDF), polyvinylidene fluoride-hexafluoropropylene (PVDF-HFP), polypropylene oxide (PPO), polyacrylonitrile (PAN), polymethacrylonitrile (PMAN), polymethyl methacrylate (PMMA), their corresponding oligomers and copolymers, and combinations thereof.

[0009] In other features, the solid electrolyte is selected from oxide-based solid electrolytes, metal-doped or asymmetrically substituted oxide-based electrolytes, sulfide-based electrolytes, nitride-based electrolytes, hydride-based electrolytes, halide-based electrolytes, borate-based electrolytes, and combinations thereof.

[0010] A method for manufacturing a free-standing composite gel film for a battery cell includes providing a polymer film; supplying a slurry for the composite gel film onto the polymer film, the slurry comprising a polymer, a solid electrolyte accounting for greater than 20 weight percent of the composite gel film, and an initiator; compressing the slurry and the polymer film between a first roller and a second roller; and exposing the slurry to ultraviolet (UV) light at a predetermined wavelength for a predetermined period of time to polymerize the polymer.

[0011] In other features, at least one of the first roller and the second roller includes a radially outer surface comprising one of rubber and plastic. The predetermined time period is 30 to 600 seconds. The predetermined wavelength is 10 to 400 nanometers. The energy of the ultraviolet light is 0.5 J / cm³ to 3 J / cm³. The polymer comprises 5 to 30 weight percent of the composite gel film, the solid electrolyte comprises 20 to 90 weight percent of the composite gel film, and the initiator comprises 0.1 to 1.0 weight percent of the composite gel film.

[0012] In other features, the polymer is selected from polyethylene oxide (PEO), polyvinylidene fluoride (PVDF), polyvinylidene fluoride-hexafluoropropylene (PVDF-HFP), polypropylene oxide (PPO), polyacrylonitrile (PAN), polymethacrylonitrile (PMAN), polymethyl methacrylate (PMMA), their corresponding oligomers and copolymers, and combinations thereof. The solid electrolyte is selected from oxide-based solid electrolytes, metal-doped or asymmetrically substituted oxide-based electrolytes, sulfide-based electrolytes, nitride-based electrolytes, hydride-based electrolytes, halide-based electrolytes, borate-based electrolytes, and combinations thereof.

[0013] A method for making a free-standing electrode and separator for a battery cell includes providing an electrode; supplying a slurry for a composite gel membrane onto the electrode, the slurry comprising a polymer, a solid electrolyte comprising greater than 20 weight percent of the composite gel membrane, and an initiator; compressing the slurry and the electrode between a first roller and a second roller; and exposing the slurry to ultraviolet (UV) light at a predetermined wavelength for a predetermined period of time to polymerize the polymer.

[0014] In other features, at least one of the first roller and the second roller includes a radially outer surface comprising one of rubber and plastic. The predetermined time period is 30 to 600 seconds. The predetermined wavelength is 10 to 400 nm. The energy of the ultraviolet light is 0.5 J / cm³ to 3 J / cm³.

[0015] In other features, the polymer accounts for 5 wt% to 30 wt% of the composite gel film, the solid electrolyte accounts for 20 wt% to 90 wt% of the composite gel film, and the initiator accounts for 0.1 wt% to 1.0 wt% of the composite gel film. The polymer is selected from polyethylene oxide (PEO), polyvinylidene fluoride (PVDF), polyvinylidene fluoride-hexafluoropropylene (PVDF-HFP), polypropylene oxide (PPO), polyacrylonitrile (PAN), polymethacrylonitrile (PMAN), polymethyl methacrylate (PMMA), and their corresponding oligomers and copolymers. The solid electrolyte is selected from oxide-based solid electrolytes, metal-doped or asymmetrically substituted oxide-based electrolytes, sulfide-based electrolytes, nitride-based electrolytes, hydride-based electrolytes, halide-based electrolytes, and borate-based electrolytes.

[0016] The present invention discloses the following solutions:

[0017] Solution 1. A battery cell comprising:

[0018] A anode electrode;

[0019] C cathode electrodes; and

[0020] S separators are arranged between A anode electrodes and C cathode electrodes, wherein A, C and S are integers greater than 1,

[0021] The S separators include a composite gel film that is in-situ cured using ultraviolet light and includes a polymer, a solid electrolyte that accounts for more than 20 weight percent of the composite gel film, an initiator, and a liquid electrolyte.

[0022] Option 2. The battery cell of Option 1, wherein the polymer accounts for 5 to 30 weight percent of the composite gel film, the solid electrolyte accounts for 20 to 90 weight percent of the composite gel film, the initiator accounts for 0.1 to 0.25 weight percent of the composite gel film, and the liquid electrolyte accounts for 10 to 80 weight percent of the composite gel film.

[0023] Option 3. A battery cell according to Option 1, wherein the polymer accounts for 8 wt% to 15 wt% of the composite gel film, the solid electrolyte accounts for 35 wt% to 60 wt% of the composite gel film, the liquid electrolyte accounts for 10 wt% to 15 wt% of the composite gel film, and the initiator accounts for 0.1 wt% to 0.25 wt% of the composite gel film.

[0024] 4. The battery cell of 1, wherein the initiator is selected from the group consisting of a Norish type 1 initiator and a Norish type 2 initiator.

[0025] Option 5. The battery cell of Option 1, wherein the liquid electrolyte comprises one or more solvents and one or more lithium salts.

[0026] Option 6. A battery cell according to Option 5, wherein the liquid electrolyte further comprises a solid electrolyte interface additive selected from vinylene carbonate (VC), vinyl ethylene carbonate (VEC), butylene carbonate (BC), fluoroethylene carbonate (FEC), 1,3-propane sultone (PS), ethylene sulfite (ES), ethylene sulfate (DTD) and combinations thereof.

[0027] Item 7. The battery cell of Item 5, wherein the one or more lithium salts have a concentration greater than or equal to 0.8 M / L.

[0028] Option 8. The battery cell of Option 5, wherein the one or more solvents are selected from ethylene carbonate (EC), dimethyl carbonate (DMC), gamma-butyrolactone (GBL), propylene carbonate (PC), ethyl methyl carbonate (EMC), diethyl carbonate (DEC), and combinations thereof.

[0029] Option 9. A battery cell according to Option 1, wherein the polymer is selected from polyethylene oxide (PEO), polyvinylidene fluoride (PVDF), polyvinylidene fluoride-hexafluoropropylene (PVDF-HFP), polypropylene oxide (PPO), polyacrylonitrile (PAN), polymethacrylonitrile (PMAN), polymethyl methacrylate (PMMA), their corresponding oligomers and copolymers, and combinations thereof.

[0030] Option 10. A battery cell according to Option 1, wherein the solid electrolyte is selected from oxide-based solid electrolytes, metal-doped or asymmetrically substituted oxide-based electrolytes, sulfide-based electrolytes, nitride-based electrolytes, hydride-based electrolytes, halide-based electrolytes, borate-based electrolytes, and combinations thereof.

[0031] 11. A method for making a free-standing composite gel film for a battery cell, comprising:

[0032] providing a polymer film;

[0033] supplying a slurry for a composite gel membrane onto the polymer membrane, the slurry comprising a polymer, a solid electrolyte accounting for more than 20 wt % of the composite gel membrane, and an initiator;

[0034] compressing the slurry and the polymer film between a first roller and a second roller; and

[0035] The slurry is exposed to ultraviolet (UV) light at a predetermined wavelength for a predetermined period of time to polymerize the polymer.

[0036] Option 12. The method of Option 11, wherein at least one of the first roller and the second roller includes a radially outer surface comprising one of rubber and plastic.

[0037] Item 13. The method according to item 11, wherein:

[0038] The predetermined time period is 30 to 600 seconds,

[0039] The predetermined wavelength is 10 to 400 nanometers, and

[0040] The energy of the UV light is 0.5 J / cm 3 Up to 3J / cm 3 .

[0041] Option 14. The method according to Option 11, wherein the polymer accounts for 5 wt% to 30 wt% of the composite gel film, the solid electrolyte accounts for 20 wt% to 90 wt% of the composite gel film, and the initiator accounts for 0.1 wt% to 1.0 wt% of the composite gel film.

[0042] Item 15. The method according to item 11, wherein:

[0043] The polymer is selected from polyethylene oxide (PEO), polyvinylidene fluoride (PVDF), polyvinylidene fluoride-hexafluoropropylene (PVDF-HFP), polypropylene oxide (PPO), polyacrylonitrile (PAN), polymethacrylonitrile (PMAN), polymethyl methacrylate (PMMA), their corresponding oligomers and copolymers, and combinations thereof, and

[0044] The solid electrolyte is selected from oxide-based solid electrolytes, metal-doped or alivalently substituted oxide-based electrolytes, sulfide-based electrolytes, nitride-based electrolytes, hydride-based electrolytes, halide-based electrolytes, borate-based electrolytes, and combinations thereof.

[0045] 16. A method for making a free-standing electrode and separator for a battery cell, comprising:

[0046] providing electrodes;

[0047] supplying a slurry for a composite gel membrane onto the electrode, the slurry comprising a polymer, a solid electrolyte accounting for more than 20 weight % of the composite gel membrane, and an initiator;

[0048] compressing the slurry and the electrode between a first roller and a second roller; and

[0049] The slurry is exposed to ultraviolet (UV) light at a predetermined wavelength for a predetermined period of time to polymerize the polymer.

[0050] Option 17. The method of Option 16, wherein at least one of the first roller and the second roller includes a radially outer surface comprising one of rubber and plastic.

[0051] 18. The method according to claim 1 or 7, wherein:

[0052] The predetermined time period is 30 to 600 seconds,

[0053] The predetermined wavelength is 10 to 400 nm, and

[0054] The energy of the UV light is 0.5 J / cm 3 Up to 3J / cm 3 .

[0055] Option 19. The method according to Option 17, wherein the polymer accounts for 5 wt% to 30 wt% of the composite gel film, the solid electrolyte accounts for 20 wt% to 90 wt% of the composite gel film, and the initiator accounts for 0.1 wt% to 1.0 wt% of the composite gel film.

[0056] Item 20. The method of item 18, wherein:

[0057] The polymer is selected from polyethylene oxide (PEO), polyvinylidene fluoride (PVDF), polyvinylidene fluoride-hexafluoropropylene (PVDF-HFP), polypropylene oxide (PPO), polyacrylonitrile (PAN), polymethacrylonitrile (PMAN), polymethyl methacrylate (PMMA), and their corresponding oligomers and copolymers, and

[0058] The solid electrolyte is selected from oxide-based solid electrolytes, metal-doped or alivalently substituted oxide-based electrolytes, sulfide-based electrolytes, nitride-based electrolytes, hydride-based electrolytes, halide-based electrolytes, and borate-based electrolytes.

[0059] Further areas of applicability of the present disclosure will become apparent from the detailed description, claims, and drawings.The detailed description and specific examples are intended to be illustrative only and are not intended to limit the scope of the present disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0060] The present disclosure will be more fully understood through the detailed description and accompanying drawings, in which:

[0061] Figure 1 is a side cross-sectional view of an example of a monopolar battery cell according to the present disclosure, the monopolar battery cell including a cathode electrode, an anode electrode, and a separator disposed in a battery cell housing;

[0062] Figure 2 is a side cross-sectional view of an example of a bipolar battery cell according to the present disclosure, the bipolar battery cell including a cathode electrode, an anode electrode, and a separator disposed in a battery cell housing;

[0063] Figure 3 is a more detailed side cross-sectional view of an example of a monopolar battery cell according to the present disclosure, the monopolar battery cell including a cathode electrode, an anode electrode, and a separator disposed in a battery cell housing;

[0064] Figure 4 is a more detailed side cross-sectional view of an example of a bipolar battery cell according to the present disclosure, the bipolar battery cell including a cathode electrode, an anode electrode, and a separator disposed in a battery cell housing;

[0065] Figure 5 illustrates an example of a method for making a free-standing composite gel membrane according to the present disclosure; and

[0066] Figure 6 An example of a method for fabricating a free-standing electrode having a composite gel film according to the present disclosure is illustrated.

[0067] Among the drawings, reference numerals may be repeated to identify similar and / or identical elements. DETAILED DESCRIPTION

[0068] Although battery cells with composite gel membranes (CGMs) according to the present disclosure are illustrated in the context of electric vehicles, battery cells with CGMs may be used in stationary applications and / or other applications.

[0069] Free-standing gel films can be used as separators in solid-state batteries (SSBs). Gel films help improve interlayer contact. However, due to random defects in the gel film, internal short circuits can occur, especially when the gel film thickness is reduced to increase energy density. Using separate layers including a solid electrolyte and the gel film results in increased thickness and reduced power capacity.

[0070] Solid electrolytes (SE) are incorporated into gel membranes to achieve optimized reliability. However, the preparation of composite gel membranes with high SE concentrations and low thicknesses remains problematic due to the high viscosity of the precursor solutions. The viscosity of the precursor solution for CGM coating increases dramatically with increasing SE concentration. The high viscosity of the precursor solution makes it difficult to apply during membrane coating. For example, the viscosity of a gel precursor with 15 wt % SE is 700 MPas, the viscosity of a gel precursor with 27 wt % SE is 1200 MPas, and the viscosity of a gel precursor with 41 wt % SE is 16,800 MPas.

[0071] In some examples, a composite gel membrane (CGM) according to the present disclosure includes a solid electrolyte (SE) at a concentration greater than 40 wt. %, a polymer, an initiator, and a liquid electrolyte. The composite gel membrane is triggered by an ultraviolet (UV) light-induced process. Self-supporting CGMs and / or self-supporting electrodes including CGMs improve the power capabilities of solid-state battery cells. Additionally, the likelihood of short circuits is significantly reduced when using a CGM according to the present disclosure.

[0072] The polymer formed during the UV in-situ polymerization process serves as both the backbone of the gel electrolyte and the binder material of the CGM. In some examples, no processing solvents (e.g., such as N-methyl-2-pyrrolidone (NMP)) or heating chambers are required. As a result, battery cells using CGMs according to the present disclosure have lower manufacturing costs and higher efficiency than other comparable battery cells.

[0073] Now refer to Figure 1 The monopolar battery cell 10 includes C cathode electrodes 20, A anode electrodes 40, and S separators 32 arranged in a predetermined order in a battery cell stack 12 within a housing 50, where C, S, and A are integers greater than zero. The S separators 32 include a composite gel film as described herein.

[0074] The C cathode electrodes 20-1, 20-2, ..., and 20-C include cathode active material layers 24 disposed on one or both sides of a cathode current collector 26. The A anode electrodes 40-1, 40-2, ..., and 40-A include anode active material layers 42 disposed on one or both sides of an anode current collector 46.

[0075] In some examples, the anode active material layer 42 and / or the cathode active material layer 24 are free-standing electrodes that are disposed adjacent to (or attached to) the cathode current collector 26 and / or the anode current collector 46, respectively. In some examples, the anode active material layer 42 and / or the cathode active material layer 24 include a coating comprising one or more active materials, one or more conductive fillers / additives, and / or one or more binder materials applied to the current collector.

[0076] In some examples, the cathode current collector 26 and / or the anode current collector 46 comprises foil, mesh, or expanded metal. In some examples, the cathode current collector 26 and / or the anode current collector 46 are made of one or more materials selected from copper, stainless steel, brass, bronze, zinc, aluminum, and / or alloys thereof. External tabs 28, 48 can be connected to the current collectors of the anode and cathode electrodes on the same side or opposite sides of the battery stack. External tabs 28, 48 are connected to the terminals of the battery cells.

[0077] Now refer to Figure 2 , bipolar battery cell 100 includes C cathode electrodes 120, A anode electrodes 140, and S separators 132 arranged in a predetermined order in a cell stack 112 located in a housing 150. The S separators 132 include a composite gel film as described herein.

[0078] The C cathode electrodes 120-1, 120-2, ..., and 120-C include a cathode active material layer 124 disposed on a cathode current collector 126 of a bipolar current collector 125. The A anode electrodes 140-1, 140-2, ..., and 140-A include an anode active material layer 142 disposed on an anode current collector 146 of the bipolar current collector 125. In some examples, the cathode current collector 126 of the bipolar current collector 125 includes aluminum foil, and the anode current collector 146 of the bipolar current collector 125 includes copper foil, although other materials may also be used.

[0079] In some examples, the anode active material layer 142 and / or the cathode active material layer 124 is a free-standing electrode that is disposed adjacent to (or attached to) the bipolar current collector 125. In some examples, the anode active material layer 142 and / or the cathode active material layer 124 comprises a coating comprising one or more active materials, one or more conductive fillers / additives, and / or one or more binder materials applied to the anode or cathode layer of the current collector. In some examples, the battery cells and / or electrodes are manufactured by applying a slurry to coat the current collector in a roll-to-roll manufacturing process.

[0080] Now refer to Figure 3 , shows an example of a monopolar battery cell. The cathode active material layer 24 includes a cathode active material 210 and a solid electrolyte 212. The three separators 32 include a composite gel membrane 220. The anode active material layer 42 includes an anode active material 230 and a solid electrolyte 232.

[0081] Now refer to Figure 4 , shows an example of a bipolar battery cell. The cathode active material layer 124 includes a cathode active material 210 and a solid electrolyte 212. The three separators 132 include a composite gel membrane 220. The anode active material layer 142 includes an anode active material 230 and a solid electrolyte 232.

[0082] In some examples, the composite gel film 220 is a free-standing composite gel film comprising a polymer, a solid electrolyte, a liquid electrolyte, and / or an initiator. In some examples, the polymer comprises 5 wt% to 30 wt% of the composite gel film, the solid electrolyte comprises 20 wt% to 90 wt% of the composite gel film, the liquid electrolyte comprises 10 wt% to 80 wt% of the composite gel film, and the initiator comprises 0.1 wt% to 1.0 wt% of the composite gel film.

[0083] In some examples, the polymer accounts for 8 wt % to 15 wt % of the composite gel film, the solid electrolyte accounts for 35 wt % to 60 wt % of the composite gel film, the liquid electrolyte accounts for 10 wt % to 55 wt % of the composite gel film, and the initiator accounts for 0.1 wt % to 0.25 wt % of the composite gel film.

[0084] In some examples, the polymer is selected from polyethylene oxide (PEO), polyvinylidene fluoride (PVDF), polyvinylidene fluoride-hexafluoropropylene (PVDF-HFP), polypropylene oxide (PPO), polyacrylonitrile (PAN), polymethacrylonitrile (PMAN), polymethyl methacrylate (PMMA), their corresponding oligomers and copolymers, and combinations thereof.

[0085] In some examples, the solid electrolyte is selected from oxide-based solid electrolytes, metal-doped or alivalently substituted oxide-based electrolytes, sulfide-based electrolytes, nitride-based electrolytes, hydride-based electrolytes, halide-based electrolytes, borate-based electrolytes, and combinations thereof.

[0086] Examples of oxide-based electrolytes include garnet-type (e.g., Li7La3Zr2O 12 ), perovskite type (such as Li 3x La 2 / 3-x TiO3), NASICON type (such as Li 1.4 Al 0.4 Ti 1.6 (PO4)3 and Li 1+x Al x Ge 2-x (PO4)3), LISICON type (e.g., Li 2+2x Zn 1-x GeO4) and combinations thereof.

[0087] In some examples, low-cost electrolytes such as aluminum oxide, Al 2 O 3 , or aluminum oxyhydroxide, AlO(OH), are used.

[0088] Examples of electrolytes based on metal-doped or alivalently substituted oxides include Al (or Nb)-doped Li7La3Zr2O 12 , Sb-doped Li7La3Zr2O 12 , Ga-substituted Li7La3Zr2O 12、 Cr and V substituted LiSn2P3O 12 , Al-substituted perovskite, Li 1+x+y Al x Ti 2-x Si y P 3-y O 12 and combinations thereof.

[0089] Examples of sulfide-based electrolytes include the Li2S-P2S5 system, Li2S-P2S5-MO X system, Li2S-P2S5-MS x system, LGPS (Li 10 GeP2S 12 ), thio-LISICON(Li 3.25 Ge 0.25 P 0.75 S4) Li 3.4 Si 0.4 P 0.6 S4, Li 10 GeP2S11.7 O 0.3 、lithium argyrodite Li6PS5X (X=Cl, Br or I), Li 9.54 Si 1.74 P 1.44 S 11.7 Cl 0.3 、Li 9.6 P3S 12 、Li7P3S 11 、Li9P3S9O3、Li 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 2.19 S 12 、Li 10 (Si 0.5 Ge 0.5 )P2S 12 、Li 10 (Ge 0.5 Sn 0.5 )P2S 12 、Li 10 (Si 0.5 Sn 0.5 )P2S 12 、Li 3.833 Sn 0.833 As 0.166 S4, LiI-Li4SnS4, Li4SnS4 and combinations thereof.

[0090] Examples of nitride-based electrolytes include Li3N, Li7PN4, and LiSi2N3. Examples of hydride-based electrolytes include LiBH4, LiBH4-LiX (X = chlorine (Cl), bromine (Br), or iodine (I)), LiNH2, Li2NH, LiBH4-LiNH2, and Li3AlH6. Examples of halide-based electrolytes include LiI, Li3InCl6, Li2CdCl4, Li2MgCl4, Li2CdI4, Li2ZnI4, and Li3OCl. Examples of borate-based electrolytes include Li2B4O7, Li2O-B2O3-P2O5, and combinations thereof.

[0091] In some examples, the liquid electrolyte includes one or more solvents and one or more lithium salts. In some examples, the concentration of the lithium salt is greater than or equal to 0.8 M / L. In some examples, the solvent is selected from ethylene carbonate (EC), dimethyl carbonate (DMC), gamma-butyrolactone (GBL), propylene carbonate (PC), ethyl methyl carbonate (EMC), diethyl carbonate (DEC), and combinations thereof.

[0092] In some examples, the lithium salt is selected from LiTFSI, LIFSI, LiBETI, LiPF6, LiBOB, LiDFOB, LiBF4, LiAsF6, LiClO4, LiTfO, and combinations thereof.

[0093] In some examples, the liquid electrolyte may further include one or more solid electrolyte interface (SEI) additives. In some examples, the SEI additives are selected from vinylene carbonate (VC), vinyl ethylene carbonate (VEC), butylene carbonate (BC), fluoroethylene carbonate (FEC), 1,3-propane sultone (PS), ethylene sulfite (ES), ethylene sulfate (DTD), and combinations thereof.

[0094] In some examples, the initiator is selected from a Norish Type 1 initiator and a Norish Type 2 initiator. In some examples, the Norish Type 1 initiator is selected from 2,4,6-trimethylbenzoyldiphenylphosphine oxide (TPO), hydroxyacetophenone (HAP), Irgacure 1173, Irgacure 184, Irgacure 369, Irgacure 651, and Irgacure 907. In some examples, the Norish Type 2 initiator is selected from benzophenone, 2-isopropylthioxanthone, 4-methylbenzophenone, ethyl 4-dimethylaminobenzoate, 4-chlorobenzophenone, and combinations thereof.

[0095] Now refer to Figure 5 , a method 300 for manufacturing a self-supporting composite gel film is shown. A roll 310 of polymer film 312 is fed between a pair of rollers 320 and 321. A dispenser 326 supplies a slurry 328 for the composite gel film onto one surface of the polymer film 312. Rollers 320 and 321 compress the slurry. In some examples, roll 327 supplies additional polymer film 327, which is guided by roller 327 onto the upper surface of the slurry. The additional polymer film prevents evaporation of the liquid electrolyte. After passing through rollers 320 and 321, the film and slurry pass through a UV chamber 340 for UV curing. After curing and cooling, the self-supporting composite gel film 344 is collected on a roll 350. In some examples, the polymer film 312 is removed before manufacturing a battery cell including the composite gel film.

[0096] In some examples, one or both of rollers 320 and 321 are different from metal-based rollers commonly used in roll-to-roll processes. In some examples, one or both of rollers 320 and 321 include a soft material such as rubber or plastic (e.g., PP, PTFE). In some examples, the radially outer surface of one of rollers 320 and 321 has a metal surface.

[0097] In some examples, one or both of rollers 320 and 321 have a core-shell structure. Core 322 is made of a rigid material such as metal (e.g., stainless steel), and radially outer surface 323 of core 322 comprises a material softer than metal (e.g., rubber, plastic (e.g., PP, PTFE)). In some examples, rollers 320 and 321 have a diameter of 20 mm to 500 mm. In some examples, rollers 320 and 321 have a diameter of 50 mm to 200 mm. In some examples, the pressing pressure of the roller pressure ranges from 0.01 T to 3.0 T. In some examples, the pressing pressure of the roller pressure ranges from 0.05 T to 0.5 T.

[0098] Now refer to Figure 6 , shows a method 400 for manufacturing a free-standing electrode including a composite gel film. A roll 410 including a free-standing electrode 412 (e.g., an anode or cathode electrode) is fed between a pair of rollers 320 and 321. A dispenser 326 supplies a slurry 328 for the composite gel film onto one surface of the electrode 412. Rollers 320 and 321 compress the slurry 328 and the electrode 412. In some examples, a roll 327 supplies an additional polymer film 327, which is guided by roller 327 onto the upper surface of the slurry. The additional polymer film prevents evaporation of the liquid electrolyte. After passing through rollers 320 and 321, the electrode 412 and the compressed slurry 328 pass through a UV chamber 340 for UV polymerization. After UV polymerization and cooling, the free-standing electrode 444 including the composite gel film is collected on a roll 350.

[0099] In some examples, UV curing is performed at a wavelength in the range of 100 to 400 nm. In some examples, UV curing is performed at a wavelength in the range of 340 to 380 nm (e.g., 365 nm). In some examples, the energy supplied by the UV chamber is in the range of 0.25 J / cm 2 Up to 3J / cm 2 In some embodiments, the UV chamber supplies energy in the range of 0.5 J / cm 2 Up to 1.5J / cm 2 In some examples, the UV curing time is from 30 seconds to 600 seconds. In some examples, the UV curing time is from 50 seconds to 120 seconds.

[0100] In some examples, the polymer film comprises a non-stick plastic. In some examples, the non-stick plastic is selected from PET, PP, PMMA, PTFE, etc.

[0101] In some examples, the electrodes have a width of 50 mm to 500 mm. In some examples, the polymer in the CGM comprises small molecules. For example, the polymer in the CGM comprises monomers or oligomers (e.g., having a low viscosity) that are dissolved in the CGM slurry and cross-linked during UV polymerization.

[0102] In some examples, the CGM can be prepared as a free-standing separator (on a removable membrane) or a separator on a free-standing electrode (e.g., cathode and / or anode electrode). Since heating and / or solvent recovery systems are eliminated, no processing solvents are used and less electricity is consumed. The method of forming a free-standing CGM or a free-standing electrode with a CGM is relatively fast (e.g., less than 10 minutes) and is achieved through UV polymerization.

[0103] The foregoing description is merely exemplary in nature and is absolutely not intended to limit the present disclosure, its application or use. The broad teachings of the present disclosure can be implemented in various forms. Therefore, although the present disclosure includes specific examples, the true scope of the present disclosure should not be limited thereto, because after studying the drawings, the description and the following claims, other modifications will become apparent. It should be understood that one or more steps within the method may be implemented in a different order (or simultaneously) without changing the principles of the present disclosure. In addition, although each embodiment is described above as having certain features, any one or more features described with respect to any embodiment of the present disclosure may be implemented in any other embodiment and / or combined with the features of any other embodiment, even if the combination is not explicitly described. In other words, the embodiments are not mutually exclusive, and the mutual replacement of one or more embodiments is still within the scope of the present disclosure.

[0104] Various terms are used to describe spatial and functional relationships between elements (e.g., between modules, circuit elements, semiconductor layers, etc.), including "connected," "engaged," "coupled," "adjacent," "next to," "on top of," "over," "under," and "disposed." Unless explicitly described as "directly," when describing a relationship between a first element and a second element in the above disclosure, that relationship can be a direct relationship with no other intervening elements between the first element and the second element, or an indirect relationship with one or more intervening elements between the first element and the second element (spatially or functionally). As used herein, the phrase "at least one of A, B, and C" should be construed to mean a logical (A or B or C), using a non-exclusive logical OR, and should not be construed to mean "at least one of A, at least one of B, and at least one of C."

[0105] In the drawings, the direction of arrows, such as arrows, generally indicates the flow of information (e.g., data or instructions) relevant to the diagram. For example, when component A and component B exchange various information, but the information transmitted from component A to component B is relevant to the diagram, an arrow may point from component A to component B. This unidirectional arrow does not mean that no other information is transmitted from component B to component A. Furthermore, for information transmitted from component A to component B, component B may send a request for that information to component A or acknowledge receipt of that information.

Claims

1. A battery cell, comprising: A anode electrode; C cathode electrodes; and S separators are arranged between A anode electrodes and C cathode electrodes, wherein A, C and S are integers greater than 1, The S separators include a composite gel film, which is in-situ cured using ultraviolet light and includes a polymer, a solid electrolyte accounting for more than 20 weight % of the composite gel film, an initiator, and a liquid electrolyte.

2. The battery cell of claim 1, wherein the polymer accounts for 5 to 30 weight percent of the composite gel film, the solid electrolyte accounts for 20 to 90 weight percent of the composite gel film, the initiator accounts for 0.1 to 0.25 weight percent of the composite gel film, and the liquid electrolyte accounts for 10 to 80 weight percent of the composite gel film.

3. The battery cell of claim 1, wherein the polymer accounts for 8 to 15 weight percent of the composite gel film, the solid electrolyte accounts for 35 to 60 weight percent of the composite gel film, the liquid electrolyte accounts for 10 to 15 weight percent of the composite gel film, and the initiator accounts for 0.1 to 0.25 weight percent of the composite gel film.

4. The battery cell of claim 1, wherein the initiator is selected from the group consisting of a Norish Type 1 initiator and a Norish Type 2 initiator.

5. The battery cell of claim 1, wherein the liquid electrolyte comprises one or more solvents and one or more lithium salts.

6. The battery cell according to claim 5, wherein the liquid electrolyte further comprises a solid electrolyte interface additive selected from the group consisting of vinylene carbonate (VC), vinyl ethylene carbonate (VEC), butylene carbonate (BC), fluoroethylene carbonate (FEC), 1,3-propane sultone (PS), ethylene sulfite (ES), ethylene sulfate (DTD), and combinations thereof.

7. The battery cell of claim 5, wherein the one or more lithium salts have a concentration greater than or equal to 0.8 M / L.

8. The battery cell according to claim 5, wherein the one or more solvents are selected from ethylene carbonate (EC), dimethyl carbonate (DMC), gamma-butyrolactone (GBL), propylene carbonate (PC), ethyl methyl carbonate (EMC), diethyl carbonate (DEC), and combinations thereof.

9. The battery cell according to claim 1, wherein the polymer is selected from polyethylene oxide (PEO), polyvinylidene fluoride (PVDF), polyvinylidene fluoride-hexafluoropropylene (PVDF-HFP), polypropylene oxide (PPO), polyacrylonitrile (PAN), polymethacrylonitrile (PMAN), polymethyl methacrylate (PMMA), their corresponding oligomers and copolymers, and combinations thereof.

10. The battery cell according to claim 1, wherein the solid electrolyte is selected from oxide-based solid electrolytes, metal-doped or alivalently substituted oxide-based electrolytes, sulfide-based electrolytes, nitride-based electrolytes, hydride-based electrolytes, halide-based electrolytes, borate-based electrolytes, and combinations thereof.

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