Energy storage device with polymer electrolyte and filler

Abstract

Energy storage devices comprising a blend-based polymer electrolyte, a salt, and at least one filler are disclosed. The energy storage devices comprise a first electrode and a second electrode; a blend-based membrane between the first electrode and the second electrode, wherein the blend-based membrane comprises two or more polymer electrolytes; and at least one filler.

Description

Technical Field

[0001] This application generally relates to electrolytes for energy storage devices. Specifically, this application relates to polymer electrolytes and fillers for lithium (Li)-ion energy storage devices. Background Technology

[0002] Lithium-ion batteries typically include a separator, or membrane, and / or electrolyte between the anode and cathode. In one type of battery, the materials for the membrane, cathode, and anode are formed as sheets or films, respectively. The sheets of cathode, membrane, and anode are sequentially stacked or rolled so that the membrane separates the cathode from the anode (e.g., the electrode) to form the battery. A typical electrode comprises layers of electrochemically active material on a conductive metal (e.g., aluminum or copper). The membrane can be rolled or cut into parts and then stacked into a stack. The stack has alternating electrochemically active materials and membranes between them.

[0003] Si is one of the most promising anode materials for lithium-ion batteries due to its high specific gravity and volumetric capacity (3579 mAh / g and 2194 mAh / cm³). 3 Compared to graphite's 372mAh / g and 719mAh / cm³ 3 and low lithiation potential (<0.4V, relative to Li / Li) + Among the various cathodes currently available, layered lithium transition metal oxides, such as Ni-rich Li[Ni], are preferred. x Co y Mn(Al) 1-x-y Lithium nickel cobalt manganese oxide (LiNiCoMnO2 (NMC) cathode) or lithium nickel cobalt aluminum oxide (LiNiCoAlO2 (NCA) cathode) is the most promising cathode due to its high theoretical capacity (~280 mAh / g) and relatively high average operating potential (3.6 V, relative to Li / Li). + Compared to conventional lithium-ion batteries with graphite-based anodes, combining a Si anode with a high-voltage Ni-rich NMC (or NCA) cathode can deliver more energy due to the high capacity of these new electrodes.

[0004] The pairing of Si anodes with high-voltage Ni-rich cathodes can improve the energy density of lithium-ion batteries by making the battery smaller. Electric vehicles can travel longer distances on a single charge. However, both Si-based anodes and high-voltage Ni-rich NMC (or NCA) cathodes face significant technical challenges, and long-term cycle stability with high-Si anodes paired with NMC or NCA cathodes remains to be achieved. Typically, the electrolyte in conventional Si-based batteries is a liquid electrolyte based on an organic, aprotic solvent. Stable cycling is limited by the large volumetric variation of the Si anode and the unstable solid electrolyte interphase (SEI) layer in liquid organic electrolytes. Volatilization, flammability, and explosion can occur when the electrolyte is exposed to high temperatures and pressures. Therefore, safety issues remain when using organic liquid electrolytes in lithium-ion batteries and Si-based anode batteries. The dissolution of transition metal ions in liquid organic electrolytes and the structural changes of Ni-rich cathodes, as well as the anodic instability of conventional organic electrolytes on the cathode surface during cycling, can also degrade battery performance. In addition, conventional organic solvent-based liquid electrolytes may encounter volatilization, flammability, explosion, and other problems.

[0005] For anodes, silicon-based materials can provide significant improvements in energy density. However, the large volume expansion (>300%) during Li alloying and dealloying processes can lead to the breakdown of active materials and loss of conductive pathways, thus reducing battery cycle life. Furthermore, an unstable SEI layer may appear on the surface of the cycling anode, resulting in the endless exposure of the Si particle surface to the liquid electrolyte. This leads to irreversible capacity loss in each cycle due to the reduced potential of the reaction between the liquid electrolyte and the exposed surface of the Si anode. Additionally, oxidative instability of conventional non-aqueous electrolytes occurs at voltages exceeding 4.5 V, which can lead to accelerated degradation of cycling performance. Since Si typically has a poorer cycle life compared to graphite, only small amounts of Si or Si alloys are used in conventional anode materials.

[0006] NMC or NCA cathodes typically exhibit poor stability and low capacity retention at high cutoff potentials. This can be attributed to the gradual peeling of the unstable surface layer, continuous electrolyte decomposition, and the dissolution of transition metal ions into the electrolyte.

[0007] To fully utilize lithium-ion battery systems based on Si anodes / NMC or NCA cathodes, the aforementioned obstacles need to be overcome. One strategy to overcome these obstacles involves exploring new electrolytes to fully utilize Si anode / Nickel-rich cathode-based full cells. The next-generation electrolytes to be developed should be able to form a uniform and stable SEI layer on the surface of the Si anode, with increased safety, energy density, thermal stability, and reduced impedance increase and outgassing at the electrode interface. Furthermore, good mechanical and thermal properties, as well as good Li-terminus performance, are also important. + Ionic conductivity is also important. Summary of the Invention

[0008] In some aspects, energy storage devices are provided. In some embodiments, the energy storage device includes a first electrode and a second electrode, a blend-based membrane between the first and second electrodes, a lithium (Li) salt (e.g., lithium bis(trifluoromethanesulfonyl)imide (LiTFSI)), and at least one filler. In some embodiments, the blend-based membrane comprises two or more polymer electrolytes.

[0009] In some embodiments, the blend-based membrane comprises two polymeric electrolytes. In some embodiments, the blend-based membrane comprises three polymeric electrolytes. In some embodiments, two or more polymeric electrolytes include quasi-solid-state electrolytes or polymeric gel electrolytes. In some embodiments, the energy storage device further comprises a liquid electrolyte. Quasi-solid-state electrolytes and polymeric gel electrolytes can be manufactured by immersing a certain amount of liquid or standard electrolyte into the blend-based membrane.

[0010] In some embodiments, the blend-based membrane is selected from the following: PEO / PMVMA / PVA, PEO / PMVMA / cyclodextrin (CD), PEO / PMVMA / polyacrylamide (PAM), PEO / PMVMA / polysaccharide biopolymer, PEO / PMVMA / polyurethane (PU), PEO / PMVMA / R-OH, PEO / polyacrylic acid (PAA) / PVA, PEO / PAA / CD, PEO / PAA / PAM, PEO / PAA / polysaccharide biopolymer, PEO / PAA / PU, PEO / PAA / R-OH, PEO / alginate / PVA, PEO / alginate / CD, PEO / alginate / PAM, PE O / Alginate / Polysaccharide Biopolymer, PEO / Alginate / PU, PEO / Alginate / R-OH, PEO / R-COOH / R'-OH, Poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP) / PMVMA / PVA, PVDF-HFP / PMVMA / CD, PVDF-HFP / PMVMA / PAM, PVDF-HFP / PMVMA / Polysaccharide Biopolymer, PVDF-HFP / PMVMA / PU, PVDF-HFP / PMVMA / R-OH, PVDF-HFP / PAA / PVA, PVDF-HFP / PAA / CD, PVDF-HFP / PAA / PAM, PVDF -HFP / PAA / Polysaccharide Biopolymer, PVDF-HFP / PAA / PU, PVDF-HFP / PAA / R-OH, PVDF-HFP / Alginate / PVA, PVDF-HFP / Alginate / CD, PVDF-HFP / Alginate / PAM, PVDF-HFP / Alginate / Polysaccharide Biopolymer, PVDF-HFP / Alginate / PU, PVDF-HFP / Alginate / R-OH, PVDF-HFP / R-COOH / R'-OH, Polyacrylonitrile (PAN) / PMVMA / PVA, PAN / PMVMA / CD, PAN / PMVMA / PAM, PAN / PMVMA / Polysaccharide Biopolymer Polymers, PAN / PMVMA / PU, PAN / PMVMA / R-OH, PAN / PAA / PVA, PAN / PAA / CD, PAN / PAA / PAM, PAN / PAA / polysaccharide biopolymer, PAN / PAA / PU, PAN / PAA / R-OH, PAN / alginate / PVA, PAN / alginate / CD, PAN / alginate / PAM, PAN / alginate / polysaccharide biopolymer, PAN / alginate / PU, PAN / alginate / R-OH, PAN / R-COOH / R'-OH, Poly(methyl methacrylate) (PMMA) / PMVMA / PVA, PMMA / PMVMA / CD,PMMA / PMVMA / PAM, PMMA / PMVMA / polysaccharide biopolymer, PMMA / PMVMA / PU, PMMA / PMVMA / R-OH, PMMA / PAA / PVA, PMMA / PAA / CD, PMMA / PAA / PAM, PMMA / PAA / polysaccharide biopolymer, PMMA / PAA / PU, PMMA / PAA / R-OH, PMMA / alginate / PVA, PMMA / alginate / CD, PMMA / alginate / PAM, PMMA / alginate / polysaccharide biopolymer, PMMA / alginate / PU, PMMA / alginate / R-OH, and PMMA / R-COOH / R'-OH.

[0011] In some embodiments, the filler is selected from: SiO2, Al2O3, TiO2, Li3N, NiO, CuO, CeO2, Sm2O3, Li ion conductors, metal oxides, metal-organic frameworks (MOFs), and active ceramic particles.

[0012] In some embodiments, the first electrode is a cathode selected from: Ni-rich lithium nickel cobalt manganese oxide LiNiCoMnO2 (NMC) cathode, Ni-rich lithium nickel cobalt aluminum oxide LiNiCoAlO2 (NCA) cathode, LiCoO2 cathode, and lithium-rich xLi2Mn3·(1-x)LiNi a Co b Mn c O2 cathode, nickel-rich layered cobalt oxide (LiNi) 1-x Co x O2) cathode, nickel-rich layered manganese oxide (LiNi) 1-x Mn x O2) cathode, nickel-rich layered aluminum oxide (LiNi) 1-x Al x O2) cathode, lithium-rich layered cobalt oxide (LiNi) 1+x Co 1-x O2) cathode, lithium-rich layered manganese oxide (LiNi) 1+x Mn 1-x O2) cathode, lithium-rich layered nickel oxide (LiNi2O2) cathode, high-voltage spinel oxide (LiNi) 0.5 Mn 1.5 O4) cathode, high-voltage phosphate cathode, high-voltage sulfate cathode and high-voltage silicate cathode.

[0013] In some embodiments, the second electrode is a Si-based anode. In some embodiments, the polymer electrolyte includes a quasi-solid-state electrolyte or a polymer gel electrolyte. In some embodiments, the second electrode is a Si-dominant electrode.

[0014] In some embodiments, the second electrode is a high-energy-density, high-load electrode. In some embodiments, the second electrode has a capacity equal to or greater than about 10 mAh / cm³. 2 Approximately 11mAh / cm 2 Approximately 11.5 mAh / cm 2 Approximately 12mAh / cm 2 or approximately 13mAh / cm 2 The total capacity load. In some embodiments, the energy storage device has a per-electrode capacity equal to or greater than about 4 mAh / cm³. 2 Approximately 5mAh / cm 2 or approximately 6mAh / cm 2 The loop capacity. Attached Figure Description

[0015] Figure 1 A membrane based on a synthetic ternary PEO / PMVMA / PVA blend loaded with SiO2 and LiTFSI is shown.

[0016] Figure 2A and Figure 2B The dQ / dV curves during charging (A) and discharging (B) are shown for an embodiment of a Si-dominated anode / NMC cathode full cell.

[0017] Figure 3A and Figure 3B The capacity retention (A) and normalized capacity retention (B) of the Si-dominated anode / / NMC cathode full cell implementation are shown respectively.

[0018] Figure 4A and Figure 4B The dQ / dV curves during charging (A) and discharging (B) of the Si-dominated anode / NCA cathode full cell embodiment are shown respectively.

[0019] Figure 5A and Figure 5B The capacity retention (A) and normalized capacity retention (B) of the Si-dominated anode / NCA cathode full cell implementation are shown respectively.

[0020] Figure 6A and Figure 6B The dQ / dV curves during charging (A) and discharging (B) are shown for an embodiment of a Si-dominated anode / NMC cathode full cell.

[0021] Figure 7A and Figure 7B The capacity retention (A) and normalized capacity retention (B) of the Si-dominated anode / / NMC cathode full cell implementation are shown respectively.

[0022] Figure 8A and Figure 8B The dQ / dV curves during charging (A) and discharging (B) of the Si-dominated anode / NCA cathode full cell embodiment are shown respectively.

[0023] Figure 9A and Figure 9B The capacity retention (A) and normalized capacity retention (B) of the Si-dominated anode / NCA cathode full cell implementation are shown respectively. Detailed Implementation

[0024] Silicon is one of the most promising anode materials for high-energy-density lithium-ion batteries due to its high gravimetric capacity and low average potential for lithiation and delithiation. Silicon-based composite electrodes, consisting of silicon particles suspended in a carbon matrix, can provide higher energy densities than industry-standard graphite electrodes when paired with high-voltage, high-capacity cathodes (e.g., NMC and NCA). However, significant challenges remain, including particle fragmentation due to volume expansion and an unstable SEI layer during prolonged cycling. Organic solvent-based electrolytes cause repeated exposure of new surfaces in the Si anode to the liquid electrolyte, leading to SEI layer formation and growth, continuous electrolyte decomposition, and low coulombic efficiency. When solvent-based electrolytes are paired with high-voltage nickel-rich cathodes (e.g., NMC and NCA), electrolyte oxidation, dissolution of transition metal ions, and subsequent crystal structure damage further degrade battery performance.

[0025] One strategy to overcome these problems involves stabilizing the intermediate phase between the electrolyte and the anode, as well as the NMC or NCA cathode, by using new electrolytes and fillers in the membrane between the two electrodes.

[0026] One such electrolyte is a pure solid-state electrolyte. In pure solid-state electrolytes, an SEI layer typically does not form on the surface of the Si anode because only Li ions are mobile and do not provide the reactants required for SEI formation to the Si anode surface. Because the Si anode is confined within the limited space formed between the current collector and the solid polymer electrolyte membrane, morphological changes in Si-based anodes are prevented in solid-state electrolytes. In pure solid-state electrolytes, the lithium salt is dissolved and solvated by the polymer chains. The general requirements for solid polymer electrolytes are: (i) high ionic conductivity, (ii) thermal and electrochemical stability, and (iii) excellent mechanical properties and dimensional stability. However, sufficiently high Li ions at room temperature... + The ionic conductivity severely hinders the Li + Ion transport.

[0027] Other solid-state electrolytes (such as polymer electrolytes) can overcome some of the problems in lithium-ion batteries caused by organic liquid electrolytes, including leakage and flammability of organic solvents, as well as problems caused by inorganic solid electrolytes, including poor mechanical properties and low elastic modulus. For example, polymer electrolytes do not exhibit volatility or flammability. Furthermore, polymer electrolytes have better mechanical properties, high elastic modulus, and lower costs in terms of materials, production, and processing.

[0028] Therefore, polymer electrolytes are expected to be safer than liquid electrolytes. Solid-state electrolytes can minimize the amount of liquid electrolyte in quasi-solid-state batteries and polymer gel electrolyte-based batteries, where only a small amount of liquid electrolyte is added to the solid polymer electrolyte to help improve safety and performance. Thus, quasi-solid-state electrolytes and polymer gel electrolytes can retain these advantages.

[0029] For Ni-rich NMC or NCA cathodes, in systems with polymer electrolytes (including quasi-solid-state electrolytes and polymer gel electrolytes), the dissolution, migration, and binding processes involving transition metal ions can be minimized or prevented. This reduces the consumption of cyclic Li ions and minimizes the degradation of battery performance.

[0030] Regardless of the type of anode and cathode, quasi-solid-state electrolytes or polymer gel electrolytes can be used to provide advantages for all lithium-ion batteries. Therefore, the energy storage device includes a first electrode and a second electrode; a blend-based membrane between the first and second electrodes, wherein a blend-based membrane comprising two or more polymer electrolytes, lithium bis(trifluoromethanesulfonyl)imide (LiTFSI), and at least one filler can be used. Furthermore, the blend-based membrane serves as a separator in the energy storage device.

[0031] Systems with quasi-solid-state polymeric electrolytes and systems with polymeric gel electrolytes can be manufactured by immersing a certain amount of liquid electrolyte into a solid polymeric electrolyte membrane. For example, this amount can be greater than about 10 μl of liquid electrolyte or standard electrolyte, such as a lithium salt dissolved in an organic solvent. In some embodiments, this amount can be about 10 μl, about 20 μl, about 30 μl, about 40 μl, about 50 μl, about 60 μl, about 70 μl, about 80 μl, about 90 μl, about 100 μl, about 150 μl, about 200 μl, about 250 μl, about 300 μl, about 350 μl, or about 400 μl or more of liquid electrolyte or standard electrolyte. These systems can be used to improve conductivity before realizing systems with fully solid-state polymeric electrolytes. Systems with quasi-solid-state polymeric electrolytes can be considered systems with gel electrolytes.

[0032] In some embodiments, the first electrode is selected from: Ni-rich lithium nickel cobalt manganese oxide LiNiCoMnO2 (NMC) cathode, Ni-rich lithium nickel cobalt aluminum oxide LiNiCoAlO2 (NCA) cathode, LiCoO2 cathode, and lithium-rich xLi2Mn3·(1-x)LiNi a Co b Mn c O2 cathode, nickel-rich layered cobalt oxide (LiNi) 1-x Co x O2) cathode, nickel-rich layered manganese oxide (LiNi) 1- x Mn x O2) cathode, nickel-rich layered aluminum oxide (LiNi) 1-x Al x O2) cathode, lithium-rich layered cobalt oxide (LiNi) 1+x Co 1- x O2) cathode, lithium-rich layered manganese oxide (LiNi) 1+x Mn 1-x O2) cathode, lithium-rich layered nickel oxide (LiNi2O2) cathode, high-voltage spinel oxide (LiNi) 0.5 Mn 1.5 O4) cathode, high-voltage phosphate cathode, high-voltage sulfate cathode, and high-voltage silicate cathode. For example, a, b, and c can represent any integer. For example, x can be less than or equal to 1.

[0033] In some embodiments, the second electrode is an anode selected from: silicon (Si)-based electrodes, graphite electrodes, carbon-based electrodes, alloy electrodes comprising Si, germanium (Ge), tin (Sn), or antimony (Sb), titanium oxide electrodes, metal oxide electrodes, metal fluorine electrodes, metal phosphide electrodes, metal sulfide electrodes, and metal nitride electrodes. In some embodiments, the second electrode is a Si-based electrode. In some embodiments, the second electrode is a Si-based anode; more preferably, a Si-dominant anode.

[0034] In some embodiments, the blend-based membrane is selected from the following: PEO / PMVMA / PVA, PEO / PMVMA / cyclodextrin (CD), PEO / PMVMA / polyacrylamide (PAM), PEO / PMVMA / polysaccharide biopolymer, PEO / PMVMA / polyurethane (PU), PEO / PMVMA / R-OH, PEO / polyacrylic acid (PAA) / PVA, PEO / PAA / CD, PEO / PAA / PAM, PEO / PAA / polysaccharide biopolymer, PEO / PAA / PU, PEO / PAA / R-OH, PEO / alginate / PVA, PEO / alginate / CD, PEO / alginate / PAM, PE O / Alginate / Polysaccharide Biopolymer, PEO / Alginate / PU, PEO / Alginate / R-OH, PEO / R-COOH / R'-OH, Poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP) / PMVMA / PVA, PVDF-HFP / PMVMA / CD, PVDF-HFP / PMVMA / PAM, PVDF-HFP / PMVMA / Polysaccharide Biopolymer, PVDF-HFP / PMVMA / PU, PVDF-HFP / PMVMA / R-OH, PVDF-HFP / PAA / PVA, PVDF-HFP / PAA / CD, PVDF-HFP / PAA / PAM, PVDF -HFP / PAA / Polysaccharide Biopolymer, PVDF-HFP / PAA / PU, PVDF-HFP / PAA / R-OH, PVDF-HFP / Alginate / PVA, PVDF-HFP / Alginate / CD, PVDF-HFP / Alginate / PAM, PVDF-HFP / Alginate / Polysaccharide Biopolymer, PVDF-HFP / Alginate / PU, PVDF-HFP / Alginate / R-OH, PVDF-HFP / R-COOH / R'-OH, Polyacrylonitrile (PAN) / PMVMA / PVA, PAN / PMVMA / CD, PAN / PMVMA / PAM, PAN / PMVMA / Polysaccharide Biopolymer Polymers, PAN / PMVMA / PU, PAN / PMVMA / R-OH, PAN / PAA / PVA, PAN / PAA / CD, PAN / PAA / PAM, PAN / PAA / polysaccharide biopolymer, PAN / PAA / PU, PAN / PAA / R-OH, PAN / alginate / PVA, PAN / alginate / CD, PAN / alginate / PAM, PAN / alginate / polysaccharide biopolymer, PAN / alginate / PU, PAN / alginate / R-OH, PAN / R-COOH / R'-OH, Poly(methyl methacrylate) (PMMA) / PMVMA / PVA, PMMA / PMVMA / CD,PMMA / PMVMA / PAM, PMMA / PMVMA / polysaccharide biopolymer, PMMA / PMVMA / PU, PMMA / PMVMA / R-OH, PMMA / PAA / PVA, PMMA / PAA / CD, PMMA / PAA / PAM, PMMA / PAA / polysaccharide biopolymer, PMMA / PAA / PU, PMMA / PAA / R-OH, PMMA / alginate / PVA, PMMA / alginate / CD, PMMA / alginate / PAM, PMMA / alginate / polysaccharide biopolymer, PMMA / alginate / PU, PMMA / alginate / R-OH, and PMMA / R-COOH / R'-OH.

[0035] In some embodiments, the polysaccharide biopolymer is selected from starch, cellulose, chitin, chitosan, xanthan gum, guar gum, and pullulan.

[0036] In some embodiments, the blend-based membrane is selected from the following: PEO / alginate, PEO / HOOC-R-OH, PVDF-HFP / alginate, PVDF-HFP / HOOC-R-OH, PAN / alginate, PAN / HOOC-R-OH, PMMA / alginate, and PMMA / HOOC-R-OH.

[0037] Li polymer electrolyte + Ionic conductivity can be enhanced by incorporating at least one filler into the polymer electrolyte membrane to form a polymer blend-based composite material. In some embodiments, the filler is inorganic. In some embodiments, the filler can kinetically inhibit polymer chain recombination and promote the dissociation of Li salt and Li. + Ion movement. The physical properties of the inorganic-organic mixed electrolyte system, such as thermal and mechanical stability, can be modulated. In some embodiments, the filler is selected from: SiO2, Al2O3, TiO2, Li3N, NiO, CuO, CeO2, Sm2O3, Li ion conductors, metal oxides, metal-organic frameworks (MOFs), and active ceramic particles.

[0038] In some embodiments, the active ceramic particles may be selected from: LISICON-type ceramics, NASICON-type sodium superionic conductor ceramics, garnet-like structure ceramics, oxide-based perovskite ceramics, sulfide-based glassy and glassy ceramics, Thio-LiSICONS ceramics, LiPON-based ceramics, Li-silver germanite, Li3PO4, Li3N, Li halides, and Li hydrides. In some embodiments, the filler is an active filler. In some embodiments, the filler is an inactive filler.

[0039] In some embodiments, the second electrode is a high-energy-density, high-load anode. In some embodiments, the second electrode has a capacity equal to or greater than about 10 mAh / cm³. 2 Approximately 11mAh / cm 2 Approximately 11.5 mAh / cm 2 Approximately 12mAh / cm 2 or approximately 13mAh / cm 2 The total capacity load. In some embodiments, the energy storage device has a per-electrode capacity equal to or greater than about 4 mAh / cm³. 2 Approximately 5mAh / cm 2 or approximately 6mAh / cm 2 The loop capacity.

[0040] Energy storage devices

[0041] The polymer electrolyte and at least one filler described herein can be advantageously used in energy storage devices. Energy storage devices can include batteries, capacitors, and battery-capacitor hybrids. In some embodiments, the energy storage device is a lithium-ion battery. The energy storage device includes a first electrode and a second electrode, such as a cathode and an anode. For lithium-ion batteries, any electrode suitable for lithium-ion batteries can be used. In some embodiments, at least one electrode can be a Si-based electrode. In some embodiments, the Si-based electrode is a Si-dominant electrode, wherein silicon is the primary active material used in the electrode (e.g., greater than 50% silicon). In some embodiments, the energy storage device includes a blend-based membrane between the first and second electrodes.

[0042] In some embodiments, the energy storage device comprises two or more polymeric electrolytes. In some embodiments, the polymeric electrolyte can be a quasi-solid-state electrolyte or a gel electrolyte. In some embodiments, the quasi-solid-state electrolyte or polymeric gel electrolyte can be manufactured by immersing a certain amount of liquid or standard electrolyte into the membrane. For example, the polymeric electrolyte comprises 100 μl of liquid electrolyte formulated with 0.45 M LiTFSI in FEC / EMC (3 / 7 wt%). For example, the polymeric electrolyte comprises 100 μl of standard electrolyte formulated with 1.2 M LiPF6 in FEC / EMC (3 / 7 wt%).

[0043] electrode

[0044] In some embodiments, the first electrode is a cathode. The cathode for the energy storage device may comprise a Li transition metal oxide cathode material, such as lithium cobalt oxide (LiCoO2) (LCO), lithium-rich (Li) oxide / layered oxide, nickel-rich (Ni) oxide / layered oxide, high-voltage spinel oxide, and high-voltage polyanionic compound. Ni-rich oxide / layered oxide may include lithium nickel cobalt manganese oxide (LiNiO2). x Co y Mn z O2, x+y+z=1, "NMC"), lithium nickel cobalt aluminum oxide (LiNi a Co b Al c O2, a+b+c=1, "NCA"), LiNi 1-x M x O2 and LiNi 1+x M 1-x O2 (where M = Co, Mn, or Al). Examples of NMC materials include LiNi. 0.6 Co 0.2 Mn 0.2 O2 (NCM-622), NMC-111, NC-433, NMC-523, NMC-811, and NMC-90.5 0.5. Li-rich oxides / layered oxides may include Li y Ni 1+x M 1-x O2 (where y>1 and M=Co, Mn or Al), xLi2MnO3·(1-x)LiNi a Co b Mn c O2 and xLi2Mn3O2·(1-x)LiNi a Co b Mn c O2. High-voltage spinel oxides may include lithium manganese spinel (LiMn2O4, "LMO") or lithium nickel manganese spinel (LiNi). 0.5 Mn 1.5 O4 (“LNMO”). High-voltage polyanionic compounds can include phosphates, sulfates, silicates, titanates, etc. An example of a polyanionic compound is lithium iron phosphate (LiFePO4, “LFP”).

[0045] The second electrode can be the anode. The anode can be of any type suitable for lithium-ion batteries. For example, the anode can be a graphite electrode, a carbon-based electrode, an alloy electrode containing Si, germanium (Ge), tin (Sn), or antimony (Sb), a titanium oxide electrode, a metal oxide electrode, a metal fluorine electrode, a metal phosphide electrode, a metal sulfide electrode, or a metal nitride electrode. The metals used for metal oxide electrodes, metal fluorine electrodes, metal phosphide electrodes, metal sulfide electrodes, and metal nitride electrodes can be Fe, Co, Ni, Mn, Cu, Cr, Mo, etc.

[0046] In some embodiments, silicon can be used as the active material of the anode to increase the volumetric energy density and gravimetric energy density of lithium-ion batteries. Therefore, anodes for energy storage devices include Si-based anodes. Various types of silicon materials (e.g., silicon nanopowders, silicon nanofibers, porous silicon, and ball-milled silicon) are viable candidates for active materials used in the anode. Alternatively, as described in U.S. Patent Applications Nos. 13 / 008,800 and 13 / 601,976, entitled “Composite Materials for Electrochemical Storage” and “Silicon Particles for Battery Electrodes”, respectively, the Si-based anode may also contain a composite film comprising silicon particles distributed in a carbon phase. The Si-based anode may contain one or more types of carbon phases. At least one of these carbon phases is a substantially continuous phase extending across the entire film and holding the composite film together. Si particles are distributed throughout the composite film.

[0047] Composite membranes can be formed by pyrolyzing a mixture comprising a precursor (e.g., a polymer or polymer precursor) and Si particles. This mixture may optionally further contain graphite particles. The pyrolysis of the precursor forms pyrolytic carbon and produces one or more types of carbon phases. In some embodiments, the composite membrane can have a self-supporting monolithic structure and is therefore a self-supporting composite membrane. Because the precursor is converted into a conductive and electrochemically active matrix, the resulting electrode is sufficiently conductive, thereby allowing for the omission or minimization of metal foil or mesh current collectors in some cases. The converted polymer can also act as a buffer against the expansion of Si particles during cycling, enabling high cycle life. In some embodiments, the resulting electrode is an electrode composed primarily of active material. The electrode can have a high energy density of about 500 mAh / g to about 1200 mAh / g. The composite membrane can also be used as a cathode active material in some electrochemical combination with additional additives.

[0048] The amount of carbon obtained from the precursor can be from about 2 wt% to about 50 wt%, from about 2 wt% to about 40 wt%, from about 2 wt% to about 30 wt%, from about 2 wt% to about 25 wt%, or from about 2 wt% to about 20 wt% of the composite material. The carbon is obtained by heating the carbon-containing precursor at a temperature sufficient to cause pyrolysis, thus the carbon is pyrolytic carbon. The carbon from the precursor can be hard carbon and / or soft carbon. Hard carbon can be carbon that does not convert to graphite even when heated above 2800 degrees Celsius. The precursor, which melts or flows during pyrolysis, converts to soft carbon and / or graphite at sufficient temperature and / or pressure. The hard carbon phase can be the matrix phase in the composite material. Hard carbon can also be embedded in the pores of silicon-containing additives. Hard carbon can react with some additives to produce some material at the interface. For example, a silicon carbide layer or an oxygen-containing silicon carbide (Si-CO) layer can be present between the silicon particles and the pyrolytic carbon. Possible pyrolytic carbon precursors may include polyimides (or polyimide precursors), other aromatic polyimides, phenolic resins, epoxy resins, poly(p-phenylenevinylene) (PPV), poly(p-phenylene-1,3,4-oxadiazole) (POD), benzimidazole-benzophenanthrene-line ladder (BBL) polymers, and other polymers with very high melting points or crosslinking.

[0049] The amount of Si particles in the composite material can be greater than 0 wt% to about 90 wt%, about 20 wt% to about 80 wt%, about 30 wt% to about 80 wt%, or about 40 wt% to about 80 wt%. In some embodiments, the amount of Si particles in the composite material can be about 50 wt% to about 90 wt%, about 50 wt% to about 80 wt%, or about 50 wt% to about 70 wt%, and such anodes are considered Si-dominant anodes. The amount of one or more types of carbon phases in the composite material can be greater than 0 wt% to about 90 wt% or about 1 wt% to about 70 wt%. The pyrolytic / carbonized polymer can form a substantially continuous conductive carbon phase throughout the electrode, unlike particulate carbon suspended in a non-conductive binder in a class of conventional lithium-ion battery electrodes.

[0050] The maximum size of silicon particles can be less than about 40 μm, less than about 1 μm, about 10 nm to about 40 μm, about 10 nm to about 1 μm, less than about 500 nm, less than about 100 nm, and about 100 nm. All, substantially all, or at least some of the silicon particles can include the maximum sizes described above. For example, the average or median maximum size of silicon particles can be less than about 40 μm, less than about 1 μm, about 10 nm to about 40 μm, about 10 nm to about 1 μm, less than about 500 nm, less than about 100 nm, and about 100 nm. Furthermore, silicon particles can be pure silicon or may not be pure silicon. For example, silicon particles can be substantially silicon or can be silicon alloys. Silicon alloys contain silicon as a major component, along with one or more other elements.

[0051] Micrometer-sized silicon particles can provide a good combination of volumetric and gravimetric energy density with good cycle life. In some embodiments, to obtain the benefits of micrometer-sized silicon particles (e.g., high energy density) and nanometer-sized silicon particles (e.g., good cycling behavior), the silicon particles can have an average particle size in the micrometer range and a surface including nanometer-sized features. Silicon particles can have an average particle size (e.g., average diameter or average maximum size) of about 0.1 μm to about 30 μm or all values ​​from about 0.1 μm to a maximum of about 30 μm. For example, silicon particles can have the following average particle sizes: about 0.5 μm to about 25 μm, about 0.5 μm to about 20 μm, about 0.5 μm to about 15 μm, about 0.5 μm to about 10 μm, about 0.5 μm to about 5 μm, about 0.5 μm to about 2 μm, about 1 μm to about 20 μm, about 1 μm to about 15 μm, about 1 μm to about 10 μm, about 5 μm to about 20 μm, etc. Therefore, the average particle size can be any value from about 0.1 μm to about 30 μm, for example, about 0.1 μm, about 0.5 μm, about 1 μm, about 5 μm, about 10 μm, about 15 μm, about 20 μm, about 25 μm and about 30 μm.

[0052] Optionally, conductive particles, which may also be electrochemically active, may be added to the mixture. Such particles enable more conductive composites and more mechanically deformable composites capable of absorbing significant volume changes that occur during lithiation and delithiation. The maximum size of the conductive particles is from about 10 nanometers to about 100 micrometers. All, substantially all, or at least some of the conductive particles may include the maximum size described herein. In some embodiments, the average or median maximum size of the conductive particles is from about 10 nm to about 100 micrometers. The mixture may contain more than 0% by weight and up to about 80% by weight of conductive particles. The composite material may contain about 45% by weight to about 80% by weight of conductive particles. The conductive particles may be conductive carbon, including carbon black, carbon fibers, carbon nanofibers, carbon nanotubes, graphite, graphene, etc. Many carbons considered non-electrochemically active conductive additives become active once pyrolyzed in the polymer matrix. Alternatively, the conductive particles may be metals or alloys, such as copper, nickel, or stainless steel.

[0053] For example, graphite particles can be added to the mixture. Graphite can be an electrochemically active material in the battery and an elastically deformable material that can respond to volume changes in silicon particles. For certain types of lithium-ion batteries currently on the market, graphite is a preferred active anode material because of its low irreversible capacity. Additionally, graphite is softer than pyrolytic carbon and can better absorb the volume expansion of silicon additives in specific stress directions. Preferably, the maximum size of the graphite particles is from about 0.5 micrometers to about 100 micrometers. All, substantially all, or at least some of the graphite particles may include the maximum size described herein. In some embodiments, the average or median maximum size of the graphite particles is from about 0.5 micrometers to about 100 micrometers. The mixture may contain from about 2% by weight to about 50% by weight of graphite particles. The composite material may contain from about 40% by weight to about 75% by weight of graphite particles.

[0054] Composite materials can also be formed into powders. For example, composite materials can be ground into powder. Composite material powders can be used as active materials for electrodes. For example, composite material powders can be deposited on collectors in a manner similar to that used in the industrial fabrication of conventional electrode structures.

[0055] In some embodiments, the full capacity of the composite material may not be utilized during battery use to improve battery life (e.g., the number of charge and discharge cycles before battery failure or performance degradation below usable levels). For example, a composite material having about 70% by weight silicon particles, about 20% by weight carbon from a precursor, and about 10% by weight graphite can have a maximum weight capacity of about 2000 mAh / g, while the composite material may only be used at a weight capacity of about 550 mAh / g to about 850 mAh / g. Although the maximum weight capacity of the composite material may not be utilized, using the composite material at a lower capacity can still achieve a higher capacity than some lithium-ion batteries. In some embodiments, the composite material is used at or only at a weight capacity of about 70% of the maximum weight capacity of the composite material. For example, the composite material is not used at a weight capacity of more than about 70% of the maximum weight capacity of the composite material. In other embodiments, the composite material is used at or only at a weight capacity of about 50% or about 30% of the maximum weight capacity of the composite material.

[0056] Blend-based membranes

[0057] In some embodiments, the blend-based membrane comprises two or more polymeric electrolytes. In some embodiments, the blend-based membrane comprises two polymeric electrolytes. In some embodiments, the blend-based membrane comprises three polymeric electrolytes. In some embodiments, the blend-based membrane further comprises one or more fillers.

[0058] Polymer electrolyte

[0059] Poly(ethylene oxide) (PEO) is a solid polymer and possesses the ability to dissolve Li salts and high ionic conductivity at high temperatures. In some embodiments, PEO can be used as a polymer electrolyte. Poly(vinyl alcohol) (PVA) contains -OH groups and exhibits film-forming properties, hydrophilicity, and a high density of relatively functional groups that facilitate crosslinking using heat treatment. PVA also exhibits the ability to interact with complementary polymers. In some embodiments, PVA can be used as a polymer electrolyte. In some embodiments, other polymers having -OH or -NH2 groups can also be selected as polymer electrolytes.

[0060] Poly(methyl vinyl ether-alternating-maleic anhydride) (PMVMA) has a -COOH group and can act as a crosslinking agent for polymers containing -OH or -NH2 groups to obtain a three-dimensional network in polymer blends. The maleic acid or -COOH group can react with the -OH or -NH2 group. In some embodiments, PMVMA can be used as a polymer electrolyte. In some embodiments, other polymers having -COOH groups can be selected as polymer electrolytes.

[0061] Furthermore, the maleic acid groups in PMVMA or the –COOH groups in other polymers can facilitate the hydrolysis of tetraethyl orthosilicate (TEOS) or other metal salts (e.g., some Ti salts, some Al salts) to form uniformly distributed fillers (e.g., SiO2, TiO2, Al2O3, NiO, CuO, CeO2, Sm2O3, other metal oxides, and metal-organic frameworks). For example, acidic groups can replace formic acid used for hydrolyzing TEOS to obtain SiO2 for preparing polymer / SiO2-based composite membranes. This method is expected to help reduce impurities in polymer blend membranes and enhance the uniform distribution of Si powder in polymer blend-based membranes.

[0062] In some embodiments, cyclodextrin (CD) is used as the polymer electrolyte. In some embodiments, polyacrylamide (PAM) is used as the polymer electrolyte. In some embodiments, polysaccharide biopolymer blends are used as the polymer electrolyte. Polysaccharide biopolymer blends may include, for example, starch, cellulose, chitin, deacetylated chitosan, xanthan gum, guar gum, and pullulan. In some embodiments, polyurethane is used as the polymer electrolyte. In some embodiments, R-OH blend membranes are used as the polymer electrolyte. R-OH represents a polymer having -OH branched groups and is soluble in a solvent.

[0063] In some embodiments, polyacrylic acid (PAA) is used as the polymer electrolyte. In some embodiments, alginate is used as the polymer electrolyte. In some embodiments, R-COOH is used as the polymer electrolyte. R-COOH represents a polymer having a -COOH branched group and is soluble in a solvent. In some embodiments, R-COOH and R'-OH are used together as the polymer electrolyte. R and R' represent different functional groups. In some embodiments, HOOC-R-OH is used as the polymer electrolyte. HOOC-R-OH represents a polymer having –COOH and –OH groups and is soluble in a solvent.

[0064] In some embodiments, poly(vinylidene fluoride-co-hexafluoropropylene) (HVDF-HFP) is used as the polymer electrolyte. In some embodiments, polyacrylonitrile (PAN) is used as the polymer electrolyte. In some embodiments, poly(methyl methacrylate) (PMMA) is used as the polymer electrolyte.

[0065] In some embodiments, the polymer electrolyte includes a quasi-solid-state electrolyte or a polymer gel electrolyte. In some embodiments, the quasi-solid-state electrolyte or polymer gel electrolyte can be manufactured by immersing a certain amount of liquid electrolyte into a blend-based membrane.

[0066] In some embodiments, when the blend-based membrane comprises three polymer electrolytes (ternary polymer membrane), the ternary polymer membrane combination may be: PEO / PMVMA / PVA, PEO / PMVMA / CD, PEO / PMVMA / PAM, PEO / PMVMA / polysaccharide biopolymer, PEO / PMVMA / PU, PEO / PMVMA / R-OH, PEO / PAA / PVA, PEO / PAA / CD, PEO / PAA / PAM, PEO / PAA / polysaccharide biopolymer, PEO / PAA / PU, PEO / PAA / R-OH, PEO / alginate / PVA, PEO / alginate / CD, PEO / alginate / PAM, PEO / alginate / polysaccharide biopolymer, PEO / alginate / PU, PEO / alginate / R-OH, or PEO / R-COOH / R'-OH.

[0067] The PEO combination shown in the first paragraph can be PVDF-HFP, PAN, PMMA, or have a relatively high Li + Other polymer alternatives for ionic conductivity.

[0068] For example, in some embodiments, the ternary polymer membrane combination can be: PVDF-HFP / PMVMA / PVA, PVDF-HFP / PMVMA / CD, PVDF-HFP / PMVMA / PAM, PVDF-HFP / PMVMA / polysaccharide biopolymer, PVDF-HFP / PMVMA / PU, PVDF-HFP / PMVMA / R-OH, PVDF-HFP / PAA / PVA, PVDF-HFP / PAA / CD, PVDF-HFP / PAA / PAM PVDF-HFP / PAA / polysaccharide biopolymer, PVDF-HFP / PAA / PU, PVDF-HFP / PAA / R-OH, PVDF-HFP / alginate / PVA, PVDF-HFP / alginate / CD, PVDF-HFP / alginate / PAM, PVDF-HFP / alginate / polysaccharide biopolymer, PVDF-HFP / alginate / PU, PVDF-HFP / alginate / R-OH or PVDF-HFP / R-COOH / R'-OH.

[0069] For example, in some embodiments, the ternary polymer membrane combination may be: PAN / PMVMA / PVA, PAN / PMVMA / CD, PAN / PMVMA / PAM, PAN / PMVMA / polysaccharide biopolymer, PAN / PMVMA / PU, PAN / PMVMA / R-OH, PAN / PAA / PVA, PAN / PAA / CD, PAN / PAA / PAM, PAN / PAA / polysaccharide biopolymer, PAN / PAA / PU, PAN / PAA / R-OH, PAN / alginate / PVA, PAN / alginate / CD, PAN / alginate / PAM, PAN / alginate / polysaccharide biopolymer, PAN / alginate / PU, PAN / alginate / R-OH, or PAN / R-COOH / R'-OH.

[0070] For example, in some embodiments, the ternary polymer membrane combination may be: PMMA / PMVMA / PVA, PMMA / PMVMA / CD, PMMA / PMVMA / PAM, PMMA / PMVMA / polysaccharide biopolymer, PMMA / PMVMA / PU, PMMA / PMVMA / R-OH, PMMA / PAA / PVA, PMMA / PAA / CD, PMMA / PAA / PAM, PMMA / PAA / polysaccharide biopolymer, PMMA / PAA / PU, PMMA / PAA / R-OH, PMMA / alginate / PVA, PMMA / alginate / CD, PMMA / alginate / PAM, PMMA / alginate / polysaccharide biopolymer, PMMA / alginate / PU, PMMA / alginate / R-OH, and PMMA / R-COOH / R'-OH.

[0071] In some implementations, when the blend-based membrane contains two polymer electrolytes (binary polymer membrane), the binary membrane combination can be: PEO / alginate or PEO / HOOC-R-OH.

[0072] The PEO combination shown in the first paragraph can be PVDF-HFP, PAN, PMMA, or have a relatively high Li + Other polymer alternatives for ionic conductivity.

[0073] For example, in some embodiments, the binary polymer membrane combination may include, but is not limited to: PVDF-HFP / alginate or PVDF-HFP / HOOC-R-OH. For example, in some embodiments, the binary membrane combination may be: PAN / alginate or PAN / HOOC-R-OH. For example, in some embodiments, the binary membrane combination may include, but is not limited to: PMMA / alginate or PMMA / HOOC-R-OH.

[0074] filler

[0075] In some embodiments, the energy storage device includes at least one type of filler. In some embodiments, the energy storage device includes two types of filler. In some embodiments, the filler is an inorganic filler. In some embodiments, the filler is an inactive filler. In some embodiments, the filler may include, but is not limited to: SiO2, Al2O3, TiO2, Li3N, NiO, CuO, CeO2, Sm2O3, metal oxides, Li ion conductors, or metal-organic frameworks (MOFs).

[0076] In some embodiments, the filler is active ceramic particles. In some embodiments, the ceramic particles include, but are not limited to: LISICON-type ceramics, NASICON-type sodium superionic conductor ceramics, garnet-like structure ceramics, oxide-based perovskite ceramics, sulfide-based glassy and glassy ceramics, Thio-LiSICONS ceramics, LiPON (lithium phosphorus nitride)-based ceramics, Li-silver germanite, Li3PO4, Li3N, Li halides, and Li hydrides.

[0077] In some embodiments, the Li ion conductor includes LiPON, NASICON-type phosphate glass ceramic (LAGP), and Li 6.4 La3Zr 1.4 Ta 0.6 O 12 (LLZTO) and Li7La3Zr2O 12 (LLZO).

[0078] liquid electrolyte

[0079] In some embodiments, a liquid electrolyte can be added to an energy storage device comprising a blend-based membrane. The liquid electrolyte includes any standard electrolyte that can be used with lithium-ion batteries. The liquid electrolyte may contain a solvent comprising cyclic carbonates and / or linear carbonates. In some embodiments, the cyclic carbonate is a fluorinated cyclic carbonate. Examples of cyclic carbonates include fluoroethylene carbonate (FEC), difluoroethylene carbonate (DiFEC), trifluoropropylene carbonate (TFPC), ethylene carbonate (EC), ethylene carbonate (VC), propylene carbonate (PC), 4-fluoromethyl-5-methyl-1,3-dioxane-2-one (Ft-BC), 3,3-difluoropropylene carbonate (DFPC), 3,3,4,4,5,5,6,6,6-nonafluorohex-1-enyl carbonate, etc. Examples of linear carbonates include ethyl methyl carbonate (EMC), dimethyl carbonate (DMC), and diethyl carbonate (DEC), as well as some partially or fully fluorinated linear carbonates.

[0080] In some embodiments, the electrolyte may contain more than one solvent. For example, the electrolyte may contain two or more co-solvents. In some embodiments, at least one of the co-solvents in the electrolyte is a fluorinated compound, such as a fluorinated cyclic carbonate, a fluorinated linear carbonate, and / or a fluorinated ether. Examples of fluorinated compounds may include FEC, DiFEC, TFPC, Ft-PC, DFPC, 1,1,2,2-tetrafluoroethyl 2,2,3,3-tetrafluoropropyl ether, 3,3,4,4,5,5,6,6,6-nonafluorohex-1-enyl carbonate, and other partially or fully fluorinated linear carbonates, partially or fully fluorinated cyclic carbonates, and partially or fully fluorinated ethers. In some embodiments, the electrolyte contains FEC. In some embodiments, the electrolyte contains both EMC and FEC. In some embodiments, the electrolyte contains no or substantially no fluorinated cyclic carbonates, such as EC, VC, and PC. In some embodiments, the electrolyte may further contain other co-solvents, such as methyl acetate (MA), ethyl acetate (EA), methyl propionate, and γ-butyrolactone (GBL). Cyclic carbonates can facilitate the formation of the SEI layer, while linear carbonates can help dissolve Li salts and facilitate Li ion transport.

[0081] Additional components in the electrolyte can be additives or co-solvents. As used herein, an additive in an electrolyte refers to a component comprising less than 10% by weight (wt%) of the electrolyte. In some embodiments, the amount of each additive in the electrolyte can be from about 0.2 wt% to about 1 wt%, from about 0.1 wt% to about 2 wt%, from about 0.2 wt% to about 9 wt%, from about 0.5 wt% to about 9 wt%, from about 1 wt% to about 9 wt%, from about 1 wt% to about 8 wt%, from about 1 wt% to about 8 wt%, from about 1 wt% to about 7 wt%, from about 1 wt% to about 6 wt%, from about 1 wt% to about 5 wt%, from about 2 wt% to about 5 wt%, or any value between therewith. For example, the total amount of additives can be from about 1 wt% to about 9 wt%, from about 1 wt% to about 8 wt%, from about 1 wt% to about 7 wt%, from about 2 wt% to about 7 wt%, or any value between therewith.

[0082] As used herein, the co-solvent for the electrolyte has a concentration of at least about 10 wt%. In some embodiments, the co-solvent for the electrolyte may be about 20 wt%, about 40 wt%, about 60 wt%, or about 80 wt%, or about 90 wt% of the electrolyte. In some embodiments, the co-solvent may have a concentration of about 10 wt% to about 90 wt%, about 10 wt% to about 80 wt%, about 10 wt% to about 60 wt%, about 20 wt% to about 60 wt%, about 20 wt% to about 50 wt%, about 30 wt% to about 60 wt%, or about 30 wt% to about 50 wt%.

[0083] Polymer blending technology

[0084] Direct blending of different types of polymers is convenient, efficient, low-cost, and easy to implement. For example, the crystallinity of PEO can be reduced by hydrogen bonding between blended polymers. This can help improve ionic conductivity. These blended polymers can strengthen the PEO phase, further improving mechanical strength and dimensional thermal stability. Therefore, blending is an effective method for improving the ionic conductivity and mechanical strength of PEO-based films.

[0085] Besides using a certain amount of liquid electrolyte in quasi-solid-state batteries and polymer gel electrolyte-based batteries, the electrochemical performance and safety of Si anode-based lithium-ion batteries can also be improved by using different types of polymer composite solid-state polymer electrolytes. Due to the specific composition of the polymer composites and the corresponding synergistic effects between the different components, these polymer composite-based quasi-solid-state polymer electrolytes or polymer gel electrolytes can exhibit reduced Li-energy dissipation. + Ion conductivity, a wider electrochemical stability voltage window, enhanced thermal stability / mechanical properties, and reduced flammability. These can contribute to increasing the lifespan and safety of lithium-ion batteries. Furthermore, the enhanced stability and safety of quasi-solid-state or gel electrolytes based on polymer composites can also help simplify and redesign current safety measures used in lithium-ion batteries.

[0086] In some embodiments, the storage devices described herein do not burn, leak, corrode, or cause internal short circuits like purely organic liquid storage devices. Furthermore, their high fracture energy and elastic modulus, along with excellent electrode compatibility, are superior to their purely inorganic counterparts. In some embodiments, the storage devices are chemically more stable or can be inert to Si anodes and / or high-voltage Ni-rich NMC or NCA cathodes.

[0087] In some embodiments, the membrane can also function as a separator. In some embodiments, the energy storage device exhibits high thermal stability during charging and discharging, a wide electrochemical stability window against irreversible reactions, good compatibility with electrodes, enhanced Li migration number, and high total Li. + Ionic conductivity. In some embodiments, it is conceivable that the energy storage devices described herein can provide significant advantages, such as higher energy storage capacity, ease of manufacture, and low cost.

[0088] In some embodiments, the second electrode is a Si-dominant electrode. In other embodiments, the second electrode is a high-energy-density, high-load anode that does not cause the polymer composite solid electrolyte or polymer gel electrolyte to break down due to excessive expansion. Considering that conventional silicon particles expand by 100% to 300%, the high-energy-density, high-load anode described herein reduces expansion by creating a composite layer that adheres strongly to copper, allowing the anode to expand by only about 0% to 3%.

[0089] In some implementations, the energy storage device exhibits the following benefits: (a) good thermal and mechanical properties, ease of fabrication of thin films with desired shapes, and ability to form good electrode / electrolyte contacts; (b) good ionic conductivity, enhanced dimensional and mechanical stability; (c) a wide electrochemical stability window; and (d) the presence of uniformly distributed filler generated through in-situ chemical reactions in the polymer blend solution.

[0090] In some embodiments, the presence of inorganic fillers such as SiO2, Al2O3, TiO2, Li3N, and Li ion conductors can help improve the ionic conductivity of the electrolyte by modulating the Lewis acid-base interactions between the inorganic fillers. In some embodiments, the inorganic fillers are active fillers. In some embodiments, the inorganic fillers are inactive fillers.

[0091] In some embodiments, the energy storage device has a high fluorinated ethylene carbonate (FEC) content in the standard liquid electrolyte. Although conventional knowledge indicates that high FEC content is detrimental to battery performance, it has been found that using high FEC (≥30 wt%) does not cause performance impairment and instead contributes to low-expansion Si anode cycling.

[0092] It is noted that the method and the membrane exhibit good mechanical and thermal properties due to the hydrogen bonding between the PMVMA and PVA chains. Furthermore, the method and the membrane also possess good Li-related properties due to the presence of the PEO phase and the supported SiO2 filler. + Ionic conductivity. This method and the membrane also feature a uniform distribution of SiO2 filler in the ternary polymer blend-based membrane, as SiO2 is formed through a hydrolysis reaction between the -COOH groups in PMVMA and TEOS.

[0093] Example

[0094] The following exemplary devices and device manufacturing processes are generally described below, and the performance of lithium-ion batteries with different polymer electrolytes and fillers is evaluated.

[0095] Example 1

[0096] In Example 1, a membrane based on a ternary polymer blend of PEO / PMVMA / PVA loaded with SiO2 and LiTFSI was prepared. Figure 1 An example is shown of a membrane based on a PEO / PMVMA / PVA blend loaded with SiO2 and LiTFSI. By simultaneously adding some standard liquid electrolyte, the membrane is used as a solid electrolyte or polymer gel electrolyte for quasi-solid-state batteries with a Si-dominant anode and Ni-rich NMC or NCA cathode, featuring a solid separator. Because no other impurities are included in the membrane preparation process, the membrane is thin and clean.

[0097] For this synthesis, 2 g of PEO, 1 g of PMVMA, and 1 g of PVA were mixed with 76 g of deionized water. The reaction mixture was slowly heated to 80 °C with vigorous stirring and maintained at this temperature for 8 hours. The solution was then dissolved and stirred continuously for 12 hours. Then, 300 mg of LiTFSI was added with constant stirring. After another 12 hours, 1.05 g of TEOS in 4 g of ethanol was added with constant stirring. The temperature was raised to 80 °C and maintained at this temperature for another 12 hours. The pH was approximately 3. The prepared polymer solution was used to prepare a smooth polymer composite membrane using a spatula. The fabricated membrane was dried at room temperature for 24 hours and then further dried in a vacuum oven at 60 °C for 48 hours. Figure 1 As shown, this membrane (with a polymer electrolyte, quasi-solid electrolyte, or gel electrolyte) is used in a Si-dominated anode / Ni-rich NMC or NCA cathode cell, wherein a standard electrolyte added to the cell fills the pores within the anode and cathode and is partially absorbed into the membrane. The membrane exhibits good mechanical properties.

[0098] Example 2

[0099] In Example 2, the charge and discharge capacities, capacity retention and normalized capacity retention of a solid electrolyte or gel electrolyte based on a PEO / PMVMA / PVA / SiO2 / LiTFSI composite film plus 100 μl of liquid electrolyte in a Si-dominant anode / NMC cathode full cell were examined. The liquid electrolyte was formulated as 0.45 M LiTFSI in fluoroethylene carbonate (FEC) / ethyl methyl carbonate (EMC) (3 / 7 wt%).

[0100] Figure 2A and Figure 2BThe dQ / dV curves for the Si-dominated anode / NMC cathode full cell during charge (A) and discharge (B) are shown separately. The dashed line shows the charge and discharge capacity of 0.45 M LiTFSI in FEC / EMC (3 / 7 wt%), while the solid line shows the charge and discharge capacity of a solid electrolyte or gel electrolyte based on a PEO / PMVMA / PVA / SiO2 / LiTFSI composite film plus 100 μl of liquid electrolyte, wherein the liquid electrolyte is formulated as 0.45 M LiTFSI in FEC / EMC (3 / 7 wt%). Figure 2A and Figure 2B The initial formation cycle dQ / dV curves show that the fundamental electrochemistry of lithiation and delithiation is not affected by the use of polymer solid electrolytes or polymer gel electrolytes to manufacture quasi-solid-state batteries.

[0101] The Si-dominated anode comprises approximately 80 wt% Si, 5 wt% graphite, and 15 wt% glassy carbon (from resin), and is laminated on a 15 μm Cu foil. The average loading is approximately 3.8 mg / cm³. 2 The cathode contains approximately 92 wt% NMC, 4 wt% Super P, and 4 wt% PVDF5130, and is coated on a 15 μm Al foil. The average loading is approximately 23 mg / cm³. 2 The dQ / dV data were obtained through the following test procedure: charging at 0.05C to 4.2V until 0.05C, resting for 5 minutes, discharging at 0.05C to 3.1V, and resting for 5 minutes.

[0102] Figure 3A and Figure 3B The capacity retention (A) and normalized capacity retention (B) of the Si-dominated anode / / NMC cathode full cell are shown separately. As mentioned above, the electrolyte used is a solid electrolyte or polymer gel electrolyte based on a PEO / PMVMA / PVA / SiO2 / LiTFSI film plus 100 μl of liquid electrolyte, wherein the liquid electrolyte is formulated as 0.45 M LiTFSI in FEC / EMC (3 / 7 wt%). The average thickness of the PEO / PMVMA / PVA / SiO2 / LiTFSI film is approximately 60 μm. Long-term cycling consisted of charging at 0.05C to 4.2V until 0.05C, resting for 5 minutes, discharging at 0.05C to 3.1V, and resting for 5 minutes. Figure 3A and Figure 3B Examples show Si-dominant anode / NMC cathode quasi-solid-state cells with fabricated polymer solid electrolytes or polymer gel electrolytes exhibiting relatively stable cycling performance even after approximately 40 cycles. Note that the lower capacity in the last cycle does not indicate failure, but rather that the testing is still ongoing.

[0103] Example 3

[0104] In Example 3, the charge and discharge capacities, capacity retention and normalized capacity retention of a solid electrolyte or gel electrolyte based on a PEO / PMVMA / PVA / SiO2 / LiTFSI composite film plus 100 μl of liquid electrolyte in a Si-dominant anode / NCA cathode full cell were examined, wherein the liquid electrolyte was formulated as 0.45 M LiTFSI in FEC / EMC (3 / 7 wt%).

[0105] Figure 4A and Figure 4B The dQ / dV curves for the Si-dominated anode / NCA cathode full cell during charge (A) and discharge (B) are shown separately. The dashed line shows the charge and discharge capacity of 0.45 M LiTFSI in FEC / EMC (3 / 7 wt%), while the solid line shows the charge and discharge capacity of a solid electrolyte or gel electrolyte based on a PEO / PMVMA / PVA / SiO2 / LiTFSI composite film plus 100 μl of liquid electrolyte, wherein the liquid electrolyte is formulated as 0.45 M LiTFSI in FEC / EMC (3 / 7 wt%). Figure 4A and Figure 4B The initial formation cycle dQ / dV curves show that the fundamental electrochemistry of lithiation and delithiation is not affected by the use of polymer solid electrolytes or polymer gel electrolytes to manufacture quasi-solid-state batteries.

[0106] The average thickness of the PEO / PMVMA / PVA / SiO2 / LiTFSI film is approximately 60 μm. The average loading is approximately 3.8 mg / cm³. 2 The cathode contains approximately 92 wt% NCA, 4 wt% Super P, and 4 wt% PVDF5130, and is coated on a 15 μm Al foil. The average loading is approximately 23 mg / cm³. 2 dQ / dV data is obtained through the following... Figure 2A and Figure 2B The same test scheme shown is obtained.

[0107] Figure 5A and Figure 5B The capacity retention (A) and normalized capacity retention (B) of the Si-dominated anode / NCA cathode full cell are shown respectively. As mentioned above, the electrolyte used is a solid electrolyte or polymer gel electrolyte based on a PEO / PMVMA / PVA / SiO2 / LiTFSI film plus 100 μl of liquid electrolyte, wherein the liquid electrolyte is formulated as 0.45 M LiTFSI in FEC / EMC (3 / 7 wt%). The long-term cycling procedure is the same as above. Figure 3A and Figure 3B The same as mentioned in [the original text]. Figure 5A and Figure 5B Examples show Si-dominant anode / NCA cathode quasi-solid-state cells with fabricated polymer solid electrolytes or polymer gel electrolytes exhibiting relatively stable cycling performance even after approximately 30 cycles. Note that the lower capacity in the last cycle does not indicate failure, but rather that the testing is still ongoing.

[0108] Example 4

[0109] In Example 4, the charge and discharge capacities, capacity retention and normalized capacity retention of a solid electrolyte or gel electrolyte based on a PEO / PMVMA / PVA / SiO2 / LiTFSI composite film plus 100 μl of a standard electrolyte in a Si-dominant anode / NMC cathode full cell were examined. The standard electrolyte was formulated as 1.2 M LiPF6 in FEC / EMC (3 / 7 wt%).

[0110] Figure 6A and Figure 6B The dQ / dV curves for the Si-dominated anode / NMC cathode full cell during charge (A) and discharge (B) are shown separately. The dashed line shows the charge and discharge capacity of 1.2 M LiPF6 in FEC / EMC (3 / 7 wt%), while the solid line shows the charge and discharge capacity of a solid electrolyte or gel electrolyte based on a PEO / PMVMA / PVA / SiO2 / LiTFSI composite film plus 100 μl of a standard electrolyte formulated as 1.2 M LiPF6 in FEC / EMC (3 / 7 wt%). Figure 6A and Figure 6B The initial formation cycle dQ / dV curves show that the fundamental electrochemistry of lithiation and delithiation is not affected by the use of polymer solid electrolytes or polymer gel electrolytes to manufacture quasi-solid-state batteries.

[0111] The average thickness of the PEO / PMVMA / PVA / SiO2 / LiTFSI film is approximately 60 μm. The average loading is approximately 3.8 mg / cm³. 2 The cathode contains approximately 92 wt% NMC, 4 wt% Super P, and 4 wt% PVDF5130, and is coated on a 15 μm Al foil. The average loading is approximately 23 mg / cm³. 2 dQ / dV data is obtained through the following... Figure 2A and Figure 2B The same test scheme shown is obtained.

[0112] Figure 7A and Figure 7BThe capacity retention (A) and normalized capacity retention (B) of the Si-dominated anode / / NMC cathode full cell are shown respectively. As mentioned above, the electrolyte used is a solid electrolyte or polymer gel electrolyte based on a PEO / PMVMA / PVA / SiO2 / LiTFSI film plus 100 μl of standard electrolyte, wherein the standard electrolyte is formulated as 1.2 M LiPF6 in FEC / EMC (3 / 7 wt%). The long-term cycling procedure is the same as above. Figure 3A and Figure 3B The same as mentioned in [the original text]. Figure 7A and Figure 7B Examples show Si-dominant anode / NMC cathode quasi-solid-state cells with fabricated polymer solid electrolytes or polymer gel electrolytes exhibiting relatively stable cycling performance even after approximately 40 cycles. Note that the lower capacity in the last cycle does not indicate failure, but rather that the testing is still ongoing.

[0113] Example 5

[0114] In Example 5, the charge and discharge capacities, capacity retention and normalized capacity retention of a solid electrolyte or gel electrolyte based on a PEO / PMVMA / PVA / SiO2 / LiTFSI composite film plus 100 μl of a standard electrolyte in a Si-dominated anode / NCA cathode full cell were examined. The standard electrolyte was formulated as 1.2 M LiPF6 in FEC / EMC (3 / 7 wt%).

[0115] Figure 8A and Figure 8B The dQ / dV curves for the Si-dominated anode / NCA cathode full cell during charge (A) and discharge (B) are shown separately. The dashed line shows the charge and discharge capacity of 1.2 M LiPF6 in FEC / EMC (3 / 7 wt%), while the solid line shows the charge and discharge capacity of a solid electrolyte or gel electrolyte based on a PEO / PMVMA / PVA / SiO2 / LiTFSI composite film plus 100 μl of a standard electrolyte formulated as 1.2 M LiPF6 in FEC / EMC (3 / 7 wt%). Figure 6A and Figure 6B The initial formation cycle dQ / dV curves show that the fundamental electrochemistry of lithiation and delithiation is not affected by the use of polymer solid electrolytes or polymer gel electrolytes to manufacture quasi-solid-state batteries.

[0116] The average thickness of the PEO / PMVMA / PVA / SiO2 / LiTFSI film is approximately 60 μm. The average loading is approximately 3.8 mg / cm³. 2The cathode contains approximately 92 wt% NCA, 4 wt% Super P, and 4 wt% PVDF5130, and is coated on a 15 μm Al foil. The average loading is approximately 23 mg / cm³. 2 dQ / dV data is obtained through the following... Figure 2A and Figure 2B The same test scheme shown is obtained.

[0117] Figure 9A and Figure 9B The capacity retention (A) and normalized capacity retention (B) of the Si-dominated anode / / NMC cathode full cell are shown respectively. As mentioned above, the electrolyte used is a solid electrolyte or polymer gel electrolyte based on a PEO / PMVMA / PVA / SiO2 / LiTFSI film plus 100 μl of standard electrolyte, wherein the standard electrolyte is formulated as 1.2 M LiPF6 in FEC / EMC (3 / 7 wt%). The long-term cycling procedure is the same as above. Figure 3A and Figure 3B The same as mentioned in [the original text]. Figure 9A and Figure 9B Examples show Si-dominant anode / NCA cathode quasi-solid-state cells with fabricated polymer solid electrolytes or polymer gel electrolytes exhibiting relatively stable cycling performance even after approximately 20 cycles. Note that the lower capacity in the last cycle does not indicate failure, but rather that the testing is still ongoing.

[0118] Various embodiments have been described above. Although the invention has been described with reference to these specific embodiments, the description is intended to be illustrative and not limiting. Various modifications and applications can be made by those skilled in the art without departing from the true spirit and scope of the invention as defined in the appended claims.

Claims

1. An energy storage device, comprising: The first electrode is a Ni-rich cathode; The second electrode is a Si-based anode; as well as A blend-based membrane between the first electrode and the second electrode, wherein the blend-based membrane comprises two or more polymer electrolytes; Lithium bis(trifluoromethanesulfonyl)imide (LiTFSI); and At least one filler, The blend-based membranes are selected from: PEO / PMVMA / PVA, PEO / PMVMA / cyclodextrin (CD), PEO / PMVMA / polyacrylamide (PAM), PEO / PMVMA / polysaccharide biopolymer, PEO / PMVMA / polyurethane (PU), PEO / PMVMA / R-OH, PEO / polyacrylic acid (PAA) / PVA, PEO / PAA / CD, PEO / PAA / PAM, PEO / PAA / polysaccharide biopolymer, PEO / PAA / PU, PEO / PAA / R-OH, PEO / alginate / PVA, PEO / alginate / CD, PEO / alginate / PAM, PEO / alginate / polysaccharide biopolymer, PEO / alginate / PU, PEO / alginate / R-OH, PEO / R-COOH / R'-OH, and poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP). / PMVMA / PVA, PVDF-HFP / PMVMA / CD, PVDF-HFP / PMVMA / PAM, PVDF-HFP / PMVMA / Polysaccharide Biopolymer, PVDF-HFP / PMVMA / PU, PVDF-HFP / PMVMA / R-OH, PVDF-HFP / PAA / PVA, PVDF-HFP / PAA / CD, PVDF-HFP / PAA / PAM, PVDF-HFP / PAA / Polysaccharide Biopolymer, PVDF-HFP / PAA / PU, PVDF-HFP / PAA / R-OH, PVDF-HFP / Alginic Acid Salt / PVA, PVDF-HFP / Alginate / CD, PVDF-HFP / Alginate / PAM, PVDF-HFP / Alginate / Polysaccharide Biopolymer, PVDF-HFP / Alginate / PU, PVDF-HFP / Alginate / R-OH, PVDF-HFP / R-COOH / R'-OH, Polyacrylonitrile (PAN) / PMVMA / PVA, PAN / PMVMA / CD, PAN / PMVMA / PAM, PAN / PMVMA / Polysaccharide Biopolymer, PAN / PMVMA / PU, PAN / PMVMA / R-OH, PAN / PAA / PVA PAN / PAA / CD, PAN / PAA / PAM, PAN / PAA / polysaccharide biopolymer, PAN / PAA / PU, PAN / PAA / R-OH, PAN / alginate / PVA, PAN / alginate / CD, PAN / alginate / PAM, PAN / alginate / polysaccharide biopolymer, PAN / alginate / PU, PAN / alginate / R-OH, PAN / R-COOH / R'-OH, poly(methyl methacrylate) (PMMA) / PMVMA / PVA, PMMA / PMVMA / CD, PMMA / PMVMA / PAM, PMMA / PMVM A / Polysaccharide biopolymers, PMMA / PMVMA / PU, PMMA / PMVMA / R-OH, PMMA / PAA / PVA, PMMA / PAA / CD, PMMA / PAA / PAM, PMMA / PAA / Polysaccharide biopolymers, PMMA / PAA / PU, PMMA / PAA / R-OH, PMMA / Alginate / PVA, PMMA / Alginate / CD, PMMA / Alginate / PAM, PMMA / Alginate / Polysaccharide biopolymers, PMMA / Alginate / PU, PMMA / Alginate / R-OH and PMMA / R-COOH / R'-OH.

2. The energy storage device of claim 1, wherein the blend-based membrane comprises three polymer electrolytes.

3. The energy storage device of claim 1, wherein the two or more polymer electrolytes include quasi-solid electrolytes or polymer gels.

4. The energy storage device of claim 1, wherein the polysaccharide biopolymer is selected from: starch, cellulose, chitin, chitosan, xanthan gum, guar gum and pullulan.

5. The energy storage device of claim 1, wherein the blend-based membrane is selected from: PEO / alginate, PEO / HOOC-R-OH, PVDF-HFP / alginate, PVDF-HFP / HOOC-R-OH, PAN / alginate, PAN / HOOC-R-OH, PMMA / alginate, and PMMA / HOOC-R-OH.

6. The energy storage device of claim 1, wherein the at least one filler is selected from: SiO2, Li3N, Li ion conductor, metal oxide, metal-organic framework (MOF) and active ceramic particles.

7. The energy storage device of claim 6, wherein the metal oxide is selected from: Al2O3, TiO2, NiO, CuO, CeO2 and Sm2O3.

8. The energy storage device of claim 6, wherein the active ceramic particle filler is selected from: LISICON type ceramics, sodium superionic conductor (NASICON) type ceramics, garnet-like structure ceramics, oxide-based perovskite type ceramics, sulfide-based glassy and glass ceramics, thio-LiSICONS ceramics, LiPON-based ceramics, Li sulfide germanite, Li3PO4, Li3N, Li halides, and Li hydrides.

9. The energy storage device of claim 6, wherein the at least one filler is SiO2.

10. The energy storage device of claim 1, wherein the at least one filler is an active filler.

11. The energy storage device of claim 1, wherein the at least one filler is an inactive filler.

12. The energy storage device of claim 1, wherein the first electrode is a cathode selected from: Ni-rich lithium nickel cobalt manganese oxide (LiNiCoMnO2) cathode, Ni-rich lithium nickel cobalt aluminum oxide (LiNiCoAlO2) cathode, and lithium-rich xLi2Mn3 cathode. (1-x)LiNi a Co b Mn c O2 cathode, nickel-rich layered cobalt oxide LiNi 1-x Co x O2 cathode, nickel-rich layered manganese oxide LiNi 1-x Mn x O2 cathode, nickel-rich layered aluminum oxide LiNi 1-x Al x O2 cathode, lithium-rich layered cobalt oxide LiNi 1+ x Co 1-x O2 cathode, lithium-rich layered manganese oxide LiNi 1+x Mn 1-x O2 cathode, lithium-rich layered nickel oxide LiNi2O2 cathode, and high-voltage spinel oxide LiNi 0.5 Mn 1.5 O4 cathode.

13. The energy storage device of claim 1, wherein the second electrode is a Si-dominant anode.

14. The energy storage device of claim 1, wherein the total capacity of the energy storage device is equal to or greater than 10 mAh / cm2 2 .

15. The energy storage device of claim 1, wherein the energy storage device has a cyclic capacity per electrode equal to or greater than 4 mAh / cm 2 .

16. The energy storage device of claim 1, further comprising a liquid electrolyte.

Images