COMPOSITIONS AND METHODS FOR ENERGY STORAGE DEVICES INCLUDING SALTS AND/OR FOAMS
An energy storage device can include a cathode, an anode, and a separator between the cathode and the anode. At least one of the electrodes can include an electrode film prepared by a dry process. The electrode film, the electrode and/or the separator can comprise a salt, improved porosity, increased density, be prelithiated, and/or a foam. An energy storage device can include a dry composite solid polymer electrolyte (SPE) film. Processes and apparatuses used for fabricating the composite solid polymer electrolyte film, electrode and/or electrode film are also described.
1 . A method of fabricating a dry composite solid polymer electrolyte (SPE) film of an energy storage device, the method comprising:
forming a dry powder mixture comprising a dry ion conducting polymer, a dry lithium source, a dry binder, an ion conducting medium and a dry filler material; and
calendering the dry powder mixture to form a free-standing dry SPE film.
2 . The method of claim 1 , wherein the method is a dry fabrication process.
3 . The method of claim 1 , wherein forming the dry powder mixture comprises:
mixing the dry ion conducting polymer and the dry binder to form a first dry powder mixture; and
mixing the dry lithium source, the ion conducting medium and the dry filler material to form a second dry powder mixture.
4 . The method of claim 1 , wherein the dry binder is selected from the group consisting of polyethylene (PE), polytetrafluoroethylene (PTFE), and combinations thereof.
5 . The method of claim 1 , wherein forming the dry powder mixture further comprises fibrillizing the dry binder.
6 . The method of claim 1 , wherein the SPE film comprises at least about 14 wt % of the dry binder.
7 . The method of claim 1 , wherein calendering the dry powder mixture comprises a first calendering process and a second calendering process.
8 . The method of claim 7 , further comprising providing phase separation between the dry ion conducting polymer and the dry binder after the first calendering process.
9 . The method of claim 1 , wherein mixing is performed using a tumbler process, a convective process, a hopper process, a fluidization process, or a combination thereof.
10 . The method of claim 1 , wherein the dry ion conducting polymer is selected from polyethylene oxide (PEO), polyvinylidene fluoride (PVDF), poly(methylene oxide), polyoxymethylene, poly(vinyl alcohol) (PVA), poly(vinyl pyrrolidone) (PVP), poly(methyl methacrylate), poly(vinyl acetate), poly(vinylchloride), poly(oxyethylene) 9 methacrylate, poly(ethylene oxide) methyl ether methacrylate, and poly(propylenimine), and combinations thereof.
11 . The method of claim 1 , wherein the dry lithium source is selected from lithium perchlorate (LiClO 4 ), lithium tetrafluoroborate (LiBF 4 ), lithium hexafluorophosphate (LiPF 6 ), lithium bis(trifluoromethane sulfonimide) lithium (LiTFSI) (Li(C 2 F 5 SO 2 ) 2 N), bis(oxalato)borate (LiB(C 2 O 4 ) 2 ), lithium trifluoromethanesulfonate (LiCF 3 SO 3 ), lithium bis(pentafluoroethanesulfonyl)imide (C 4 F 10 LiNO 4 S 2 ), lithium bis(fluorosulfonyl)imide (F 2 LiNO 4 S 2 ), lithium difluoro(oxalato) borate (LiBF 2 (C 2 O 4 ), lithium difluorophosphate (F 2 LiO 2 P), lithium trifluorochloroborate (LiBF 3 Cl), lithium hexafluoroarsenate (LiAsF 6 ), Li 6.4 La 3 Zr 1.4 Ta 0.6 O 12 , Li 7 La 3 Zr 2 O 12 , Li 10 SnP 2 S 12 , Li 3x La 2/3−x TiO 3 (wherein 0<x<⅔), Li 0.8 La 0.6 Zr 2 (PO 4 ) 3 , Li 1+x Ti 2−x Al x (PO 4 ) 3 (wherein 0<x<2), Li 1+x+y Ti 2−x Al x Si y (PO 4 ) 3−y (wherein 0<x<2 and 0<y<3), and LiTi x Zr 2−x (PO 4 ) 3 (wherein 0<x<2), and combinations thereof.
12 . The method of claim 1 , wherein the dry filler material is a ceramic filler.
13 . The method of claim 12 , wherein the ceramic filler is selected from titanium oxide (TiO 2 ), silica (SiO 2 ), silicon oxide (SiO), copper oxide (CuO), montmorillonite ((Na,Ca) 0.33 (Al,Mg) 2 (Si 4 O 10 ), bentonite (Al 2 O 3 ·4SiO 2 H 2 O), kaolinite (Al 2 Si 2 O 5 (OH) 4 ), hectorite (Na 0.3 (Mg,Li) 3 Si 4 O 10 (OH) 2 ), and halloysite (Al 2 Si 2 O 5 (OH) 4 ), 4′-Amino-2,3′-dimethylazobenzene (CH 3 C 6 H 4 N═NC 6 H 3 (CH 3 )NH 2 ), yttrium aluminum oxide (Y 3 Al 5 O 12 ), yttrium iron oxide (Y 3 Fe 5 O 12 ) and nanoclay, and combinations thereof.
14 . The method of claim 1 , wherein the ion conducting medium is selected from nanoclay, garnet, and combinations thereof.
15 . The method of claim 1 , wherein the dry filler material and the ion conducting medium comprises nanoclay.
16 . The method of claim 1 , wherein the SPE film comprises a thickness of about 30-160 μm.
17 . The method of claim 1 , wherein the SPE film has a film density of 0.9-1.1 g/cm 3 .
18 . The method of claim 1 , wherein the SPE film comprises a loading of 14-16 mg/cm 2 .
19 . The method of claim 1 , wherein the SPE film comprises an ionic conductivity of 0.00001-0.000016 S/cm.
20 . The method of claim 1 , wherein the SPE film is absent of pores.