In-situ liquidized solid-liquid hybrid battery and preparation method and application thereof

Abstract

The application relates to a solid-liquid mixed battery in situ liquidized and a preparation method and application thereof, the solid-liquid mixed battery is composed of a positive electrode, a solid electrolyte film and a negative electrode; at least one side of the positive electrode or the negative electrode contains a first deep eutectic component, and the solid electrolyte film contains a second deep eutectic component; the positive electrode or the positive electrode containing the first deep eutectic component, the solid electrolyte film containing the second deep eutectic component, the negative electrode or the negative electrode containing the first deep eutectic component are sequentially stacked and assembled, and then the first deep eutectic component and the second deep eutectic component are in-situ formed into a deep eutectic electrolyte in a solid-liquid mixed state through pressure or heating treatment; the application overcomes the problems of poor consistency and uncontrollable molecular weight of a traditional in-situ polymerization method by in-situ forming a deep eutectic electrolyte in the battery, provides a solid-liquid mixed battery manufacturing method which is simple in process and easy to scale production, and effectively improves the electrochemical performance, cycle performance, consistency and safety of the battery.

Description

Technical Field

[0001] This invention relates to the field of battery materials technology, and in particular to an in-situ liquefied solid-liquid hybrid battery, its preparation method, and its application. Background Technology

[0002] Solid-state batteries have attracted widespread attention in pursuit of high safety and high energy density. Because they use non-flammable solid electrolytes, solid-state batteries significantly improve battery safety. However, they still face many challenges, particularly high interfacial impedance and poor cycle stability caused by poor solid-solid interface contact between the electrodes and electrolyte.

[0003] Semi-solid batteries, which combine solid and liquid phases, fall between solid-state and liquid-state batteries. They effectively alleviate solid-solid interface problems and improve battery safety to some extent. Currently, semi-solid batteries are typically prepared using in-situ solidification methods, which involve injecting an electrolyte solution containing monomers and initiators into the battery, and then using photo-initiation or thermal initiation to polymerize the monomers, thereby obtaining a polymer electrolyte.

[0004] However, this technology still faces many technical bottlenecks: First, residues trigger parasitic side reactions, impairing electrochemical performance. The presence of residual monomers, additional initiators, and oligomers can easily trigger severe parasitic reactions, leading to limited battery specific capacity, poor cycle performance, and insufficient rate capability. Electrochemical reactions occurring during cycling also affect the cell's electrical performance, further accelerating capacity decay.

[0005] Secondly, the uniformity of the polymerization reaction is difficult to control, resulting in poor product consistency. Simultaneous addition of monomers and initiators can easily lead to a sharp increase in electrolyte viscosity and a decrease in ionic conductivity; the non-uniformity of the polymerization reaction can easily cause localized stress concentration, and the monomer polymerization process may damage encapsulation components (such as aluminum-plastic films), leading to encapsulation leakage and failure. Furthermore, the uneven distribution of in-situ cured material on the electrode surface further affects the molding quality.

[0006] Third, the process is demanding and lengthy, making large-scale application difficult. The curing technology is demanding and lengthy, easily leading to common industry problems such as poor battery consistency and poor electrical performance, which limits its widespread application. At the same time, gas is inevitably generated inside the electrodes during the formation and capacity testing stage. Since the gel electrolyte has extremely poor fluidity, the gas is difficult to expel from between the electrodes, easily forming air bubbles and cavities, which damage the ion transport interface.

[0007] Therefore, there is an urgent need for a semi-solid-state battery that is stable in performance, has a controllable process, good consistency, and is easy to mass-produce. Summary of the Invention

[0008] The purpose of this invention is to address the shortcomings of existing technologies by providing an in-situ liquefied solid-liquid hybrid battery, its preparation method, and its application.

[0009] To achieve the above objectives, in a first aspect, the present invention provides a method for preparing an in-situ liquefied solid-liquid hybrid battery, the method comprising: Step S1, preparing the positive electrode, includes: adding the positive electrode active material, the first conductive agent, and the first binder to the first solvent in proportion, mixing them evenly to form a positive electrode slurry, then coating the positive electrode slurry onto the positive electrode current collector, and obtaining the positive electrode after drying and rolling. Step S2, using a metal negative electrode or preparing a negative electrode, wherein preparing a negative electrode includes: adding a negative electrode active material, a second conductive agent, and a second binder to a second solvent in proportion, mixing them evenly to form a negative electrode slurry, then coating the negative electrode slurry onto a negative electrode current collector, and obtaining a negative electrode after drying and rolling. Step S3: Coat the surface of the positive electrode and / or the negative electrode with a slurry containing the first deep eutectic component to obtain a positive electrode containing the first deep eutectic component and / or a negative electrode containing the first deep eutectic component; or, mix the first deep eutectic component into the positive electrode slurry of step S1 and / or the negative electrode slurry of step S2 to obtain a positive electrode containing the first deep eutectic component and / or a negative electrode containing the first deep eutectic component. Step S4, preparing a first solid electrolyte membrane or a second solid electrolyte membrane containing a second deep eutectic component, including any of the following methods: Method 1: Add the electrolyte material and the second deep eutectic component to the third solvent in a certain proportion, mix them evenly to form an electrolyte slurry, form the electrolyte slurry into a film by casting, scraping, or coating, and bake to remove the third solvent to obtain the first solid electrolyte film. Method 2: The second deep eutectic component, which can form a film independently, is thermally composited to form a second deep eutectic component film. The second deep eutectic component film is then composited with a separator to obtain a second solid electrolyte film. Step S5: The positive electrode or the positive electrode containing the first deep eutectic component, the first solid electrolyte membrane or the second solid electrolyte membrane, and the negative electrode or the negative electrode containing the first deep eutectic component are stacked and assembled in sequence. After assembly, pressure treatment and / or heating treatment are performed to form a deep eutectic electrolyte in a solid-liquid mixed state between the first deep eutectic component and the second deep eutectic component in situ, thereby obtaining an in-situ liquefied solid-liquid hybrid battery.

[0010] Preferably, in the first deep eutectic component and the second deep eutectic component, one is a hydrogen bond acceptor and the other is a hydrogen bond donor; The hydrogen bond acceptors include: lithium bis(fluorosulfonyl)imide (LiFSI), sodium bis(fluorosulfonyl)imide (NaFSI), lithium bis(trifluoromethanesulfonyl)imide (LiTFSI), sodium bis(trifluoromethanesulfonyl)imide (NaTFSI), potassium bis(trifluoromethanesulfonyl)imide (KTFSI), lithium trifluoromethanesulfonate (LiTfO), lithium trifluoroacetate (LiTFA), lithium hexafluorophosphate (LiPF6), sodium hexafluorophosphate (NaPF6), lithium difluorooxalate borate (LiDFOB), sodium difluorooxalate borate (NaDFOB), lithium chloride (LiCl), sodium chloride (NaCl), lithium bromide (LiBr), sodium bromide (NaBr), lithium iodide (LiI), sodium iodide (NaI), and lithium nitrate (LiNO3). Sodium nitrate (NaNO3), lithium perchlorate (LiClO4), sodium perchlorate (NaClO4), potassium carbonate (K2CO3), zinc bis(trifluoromethanesulfonyl)imide (Zn(TFSI)2), zinc chloride (ZnCl2), zinc sulfate (ZnSO4), zinc perchlorate (Zn(ClO4)2), zinc trifluoromethanesulfonate (Zn(TfO)2), zinc tetrafluoroborate (Zn(BF4)2), zinc acetate (Zn(CH3COO)2), aluminum chloride (AlCl3), choline chloride (ChCl), choline iodide (ChI), choline bromide (ChBr), choline tetrafluoroborate (ChBF4), choline nitrate (ChNO3), choline perchlorate (ChClO4), betaine (C5H) 11 NO2), tetramethylammonium chloride (TMCl), tetraethylammonium chloride (TECl), allylmethylammonium chloride (AMCl), or tetrabutylammonium chloride (TBCl); The hydrogen bond donors include: succinic anionyl nitrile (NCCH2CH2CN), acetamide (CH3CONH2), urea (CO(NH2)2), N-methylacetamide (CH3CONHCH3), N-methylurea (NH2CONHCH3), N-ethylurea (NH2CONHCH2CH3), N,N'-dimethylurea (CH3NHCONHCH3), trifluoroacetamide (CF3CONH2), N-(3-amino-3-oxopropyl)propionamide (CH3CH2CONHCH2CH2CONH2), thiourea (CS(NH2)2), methanesulfonamide (CH3SO2NH2), N-methylmethanesulfonamide (CH3SO2NHCH3), and 2-imidazolium. One or more of the following: ketone (C3H6N2O), glycerol (HOCH2CH(OH)CH2OH), ethylene glycol (HOCH2CH2OH), 2-hydroxypropionic acid (CH3CH(OH)COOH), oxalic acid (HOOCCOOH), N,N-dimethylacetamide (CH3CON(CH3)2), N,N,N',N'-tetramethylurea ((CH3)2NCON(CH3)2), dimethyl sulfone (CH3SO2CH3), γ-butyrolactone (C4H6O2), methyl pyruvate (CH3COCOOCH3), methyl acetoacetate (CH3COCH2COOCH3), or methyl 4-oxovalerate (CH3COCH2CH2COOCH3).

[0011] Preferably, the mass of the first deep eutectic component accounts for 10% to 80% of the total mass of the cathode containing the first deep eutectic component; The mass of the first deep eutectic component accounts for 10% to 80% of the total mass of the negative electrode containing the first deep eutectic component; The mass of the second deep eutectic component accounts for 30% to 80% of the total mass of the first solid electrolyte membrane; The mass of the second deep eutectic component accounts for 70% to 100% of the total mass of the second solid electrolyte membrane.

[0012] Preferably, the mass ratio of the positive electrode active material, the first conductive agent, and the first binder is 60-80:5-20:5-20; The positive electrode active material includes one or more of the following: lithium iron phosphate, lithium manganese oxide, lithium cobalt oxide, ternary materials, polyanionic salt positive electrode materials, sodium manganese oxide, sodium nickel oxide, sodium iron oxide, sodium nickel manganate, sodium nickel iron manganate, or sodium vanadium phosphate. The first conductive agent includes one or more of conductive carbon black, carbon nanotubes, carbon fibers, or graphene; the conductive carbon black includes one or more of Super P, acetylene black, and Ketjen black. The first adhesive comprises one or more of the following: polyvinylidene fluoride (PVDF), styrene-butadiene rubber (SBR), sodium carboxymethyl cellulose (CMC-Na), polyacrylic acid (PAA), polyamide (PAI), polyvinyl alcohol (PVA), polyethyleneimine (PEI), polyacrylonitrile (PAN), polyimide (PI), or polyacrylate (PAE); The first solvent includes one or more of N-methylpyrrolidone (NMP), water, acetonitrile, acetone, or dimethylformamide (DMF); The positive current collector includes: aluminum foil, carbon-coated aluminum foil, or porous aluminum foil.

[0013] Preferably, in step S2, the mass ratio of the negative electrode active material, the second conductive agent, and the second binder is 60-80: 5-20: 5-20. The metal anode includes any one of lithium metal, sodium metal, or alloy materials. The negative electrode active materials include: artificial graphite, natural graphite, soft carbon, hard carbon, modified graphite, graphene, carbon nanotubes, Schiff base compounds, carbonyl compounds, and spinel-type lithium titanate (Li4Ti5O). 12 Sodium-lithium-titanium composite oxide (Na) 0.66 [Li 0.22 Ti 0.78 O2), sodium tritiate (Na2Ti3O7), chromium-doped sodium titanate (Na 0.6 [Cr 0.6 Ti 0.4 O2), sodium titanium oxyphosphate (NaTiOPO4), NASICON-type sodium titanium phosphate (NaTi2(PO4)3), transition metal nitrides, nano-oxides or metal oxides, or one or more of these. The second conductive agent includes one or more of conductive carbon black, carbon nanotubes, carbon fibers, or graphene; the conductive carbon black includes one or more of Super P, acetylene black, and Ketjen black. The second adhesive comprises one or more of the following: polyvinylidene fluoride (PVDF), styrene-butadiene rubber (SBR), sodium carboxymethyl cellulose (CMC-Na), polyacrylic acid (PAA), polyamide (PAI), polyvinyl alcohol (PVA), polyethyleneimine (PEI), polyacrylonitrile (PAN), polyimide (PI), or polyacrylate (PAE); The second solvent includes one or more of N-methylpyrrolidone (NMP), water, acetonitrile, acetone, or dimethylformamide (DMF); The negative electrode current collector includes: copper foil, carbon-coated copper foil, or porous copper foil.

[0014] Preferably, in step S4, the mass ratio of the electrolyte material to the second deep eutectic component is 20-90:10-80; The electrolyte material includes: organic electrolyte materials and / or inorganic electrolyte materials; the organic electrolyte material includes: polyethylene oxide (PEO), 1,3,5-trioxane (TXE), polyethylene (PP), hydroxypropyl methylcellulose (HPMC), polypropylene (PE), polybutene (PB), polyvinyl alcohol (PVA), polytetrafluoroethylene (PTFE), polyethylene glycol (PEG), polyvinylidene fluoride (PVDF), cellulose acetate phthalate (CAP), polypropylene terephthalate (PTT), hydroxypropyl methylcellulose acetate succinate (HPMCAS), polybutylene terephthalate (PBT), polyethylene terephthalate (PET), polycarbonate (PC), polyimide (PI), polyvinyl chloride (PVC), polyamide (PA), polyethersulfone (PES), polyphenylene sulfide (PPS), polyethylene naphthalate (PEN), and povidone. The inorganic electrolyte material comprises one or more of the following: polyvinyl chloride (PVP), methyl cellulose (MC), ethyl cellulose (EC), hydroxypropyl cellulose (HPC), hydroxypropyl methyl cellulose phthalate (HPMCP), sodium carboxymethyl cellulose (CMC-Na), microcrystalline cellulose (MCC), sodium carboxymethyl starch (CMS-Na), crospovidone (PVPP), crospovidone carboxymethyl cellulose (CCNa), perfluorosulfonic acid resin (Nafion), perfluorosulfonic acid ion exchange membrane, or chitin nanofibers; the inorganic electrolyte material comprises one or more of the following: LLZO, LLZTO, LATP, LLTO, alumina (Al2O3), tin oxide (SnO2), zinc oxide (ZnO), aluminum phosphate (AIPO4), lithium phosphate (Li3PO4), lithium silicate (Li2SiO3), calcium silicate (CaSiO3), sulfide solid electrolyte material, or halide solid electrolyte material. The third solvent includes one or more of N-methylpyrrolidone (NMP), acetonitrile, acetone, tetrahydrofuran (THF), dimethylformamide (DMF), or water; The electrolyte slurry further includes one or more of the following: salt materials and binder materials; the temperature of the thermal composite treatment is 30℃~200℃, and the pressure is 0~200MPa; The diaphragm includes one or more of the following: polyolefin microporous diaphragm, coated modified diaphragm, nonwoven fabric diaphragm, or special diaphragm.

[0015] Further preferably, the salt material includes one or more of the following: sodium salicylate hydroquinone borate, lithium hexafluorophosphate trifluoromethanesulfonate, lithium tetraphenylborate difluorophosphate, sodium difluorophosphate, sodium dioxophosphate, sodium dioxophosphate borate, lithium dioxophosphate borate, lithium dioxophosphate borate, lithium dioxophosphate borate, sodium bis(salicylic acid-2-)borate, lithium difluorooxophosphate borate, sodium difluorooxophosphate borate, sodium 4,5-dicyano-2-(trifluoromethyl)imidazolium, lithium difluorosulfonylimide, lithium di(trifluoromethanesulfonylimide), sodium di(trifluoromethanesulfonylimide), lithium perchlorate, lithium hexafluoroarsenate, sodium perchlorate, sodium hexafluoroarsenate, sodium trifluoromethanesulfonate, lithium tetrafluoroborate, lithium hexafluorophosphate, sodium tetrafluoroborate, sodium 4,5-dicyano-2-(pentafluoroethyl)imidazolium, sodium dioxophosphate borate, sodium difluorosulfonylimide, or sodium dioxophosphate borate. The adhesive material includes one or more of the following: polyvinylidene fluoride (PVDF), styrene-butadiene rubber (SBR), sodium carboxymethyl cellulose (CMC-Na), polyacrylic acid (PAA), polyamide (PAI), polyvinyl alcohol (PVA), polyethyleneimine (PEI), polyacrylonitrile (PAN), polyimide (PI), or polyacrylate (PAE).

[0016] Preferably, the pressure of the pressurization process is 0–200 MPa; the pressurization time is from instantaneous pressurization to continuous pressurization during cyclic testing; The temperature of the heat treatment is 25℃ to 200℃; the duration of the heat treatment is from instantaneous heating to continuous heating during the cyclic test.

[0017] In a second aspect, the present invention provides a solid-liquid hybrid battery prepared by the preparation method described in the first aspect above, wherein the solid-liquid hybrid battery includes a lithium-ion solid-liquid hybrid battery or a sodium-ion solid-liquid hybrid battery.

[0018] Thirdly, the present invention provides an application of the solid-liquid hybrid battery described in the third aspect, wherein the solid-liquid hybrid battery is applied to one or more of electric vehicles, hybrid electric vehicles, electric bicycles, energy storage power stations, portable electronic devices, mobile power supplies, drones, power tools, wearable devices, medical electronic devices, aerospace vehicles, marine power systems, or grid frequency regulation energy storage systems.

[0019] The present invention provides an in-situ liquefied solid-liquid hybrid battery, its preparation method and application, which has the following technical effects.

[0020] (1) The present invention provides a method for preparing an in-situ liquefied solid-liquid hybrid battery. First, a positive electrode or a negative electrode is prepared, and a first deep eutectic component is coated on the positive electrode or a negative electrode or mixed in an electrode slurry to prepare a positive electrode or a negative electrode containing the first deep eutectic component. The second deep eutectic component is combined with an electrolyte material to form a solid electrolyte membrane. Then, the negative electrode, the solid electrolyte membrane, and the positive electrode are stacked and assembled in an inert atmosphere, and subjected to pressure and / or heat treatment to form a solid-liquid hybrid state deep eutectic electrolyte in situ with the first deep eutectic component and the second deep eutectic component, thereby obtaining a solid-liquid hybrid battery.

[0021] The preparation method provided by this invention eliminates the need for additional monomers, initiators, or crosslinking agents, completely avoiding parasitic side reactions caused by residual monomers, initiators, and oligomers in traditional in-situ curing methods. The resulting deep eutectic electrolyte exhibits high ionic conductivity and a wide electrochemical window, effectively improving the battery's specific capacity, rate performance, and cycle stability, and extending battery life.

[0022] (2) The preparation method provided by this invention results in uniform component mixing and good product consistency: the first deep eutectic component and the second deep eutectic component exist in solid form in the electrode and the solid electrolyte membrane, respectively, before the battery assembly is completed. After battery assembly, the two components are contacted and uniformly mixed by heating and / or pressurizing, avoiding the problem of uneven polymerization reaction in the traditional in-situ curing method. At the same time, since it does not involve violent polymerization exothermics and volume shrinkage, it will not damage the battery encapsulation components, effectively improving the product consistency of the battery.

[0023] (3) The preparation method provided by the present invention is simple and controllable, and suitable for large-scale production: the preparation of the positive electrode, negative electrode and solid electrolyte membrane all adopt conventional coating, casting or hot pressing processes, without the need for complex polymerization reaction control after battery assembly. The entire preparation process is short and mild, and it is easy to realize automated continuous production, meeting the requirements of large-scale industrial manufacturing.

[0024] (4) The preparation method provided by the present invention allows for easy gas discharge and avoids interface defects: During the pressurization and / or heating process after battery assembly, the deep eutectic components liquefy to form a solid-liquid mixed electrolyte with certain fluidity and wettability, which can effectively discharge the gas remaining between the electrodes, avoiding the problems of bubble cavities and interface defects caused by poor fluidity of gel electrolyte in the traditional in-situ curing method, thereby ensuring good electrode / electrolyte interface contact.

[0025] (5) The preparation method provided by the present invention allows for flexible selection of the types and ratios of hydrogen bond acceptors and hydrogen bond donors in the deep eutectic component as needed. The content of the first deep eutectic component and the second deep eutectic component can be independently controlled on the electrode side and the solid electrolyte membrane side, providing ample design space for system optimization and facilitating customized development for different active materials and battery systems.

[0026] (6) The solid-liquid hybrid battery prepared by this invention is compatible with both lithium-ion and sodium-ion battery systems and has excellent safety and cycle performance. Regarding safety, due to the inherent non-volatile and non-flammable properties of the deep eutectic electrolyte, the prepared battery is less prone to thermal runaway under extreme conditions such as high temperature and short circuits, effectively overcoming the safety hazards of flammability and explosion inherent in traditional liquid electrolytes. Regarding cycle performance, this invention has the following advantages: First, this method avoids parasitic side reactions caused by residual monomers, initiators, and oligomers in traditional in-situ solidification methods, ensuring the purity of the electrode / electrolyte interface and reducing the consumption of active materials by side reactions. Second, the in-situ formed deep eutectic electrolyte has good interfacial wettability, can closely adhere to the electrode surface, significantly reduce interfacial impedance, and ensure efficient transport of lithium or sodium ions during cycling. Third, the deep eutectic electrolyte has a certain degree of flexibility and self-healing ability, which can buffer the volume changes of electrode materials during charging and discharging, maintain stable interfacial contact, and delay contact failure. Furthermore, the solid-liquid hybrid electrolyte combines the mechanical strength of a solid electrolyte with the ion conductivity of a liquid electrolyte, suppressing lithium / sodium dendrite growth while providing a continuous ion transport channel. Through this synergistic effect, the solid-liquid hybrid battery prepared in this invention exhibits excellent cycle stability during long-term cycling.

[0027] This invention effectively solves the problems of poor interface contact, numerous side reactions, and poor consistency of traditional solid-state batteries by using in-situ liquefaction technology, thus achieving simultaneous improvement in safety performance and cycle performance. Attached Figure Description

[0028] Figure 1 This is a flowchart of a solid-liquid hybrid battery preparation method that enables in-situ liquefaction, provided by an embodiment of the present invention.

[0029] Figure 2 This is a schematic diagram of the assembly and stacking process of a solid-liquid hybrid battery that can achieve in-situ liquefaction, provided by an embodiment of the present invention.

[0030] Figure 3 This is a charge-discharge curve of a coin cell prepared using LFP material in Embodiment 1 of the present invention.

[0031] Figure 4 This is a comparison chart of the cycle coulombic efficiency and capacity retention of coin cells prepared using LFP material in Example 1 and Comparative Example 1 of the present invention.

[0032] Figure 5 This is a charge-discharge curve of a coin cell prepared using NCM622 material in Embodiment 2 of the present invention.

[0033] Figure 6 This is a comparison chart of the cycle coulombic efficiency and capacity retention of coin cells prepared using NCM622 material in Example 2 and Comparative Example 2 of the present invention.

[0034] Figure 7 This is a charge-discharge curve of a coin cell prepared using LFMP material in Embodiment 3 of the present invention.

[0035] Figure 8 This is a comparison chart of the cycle coulombic efficiency and cycle capacity of coin cells prepared using LFMP material in Example 3 and Comparative Example 3 of the present invention.

[0036] Figure 9 This is a charge-discharge curve of a coin cell prepared using LFP material in Embodiment 4 of the present invention.

[0037] Figure 10 This is a graph showing the cycle coulombic efficiency and capacity retention of a coin cell prepared using LFP material in Example 4 of this invention.

[0038] Figure 11 This is a charge-discharge curve of a coin cell prepared using LFMP material in Embodiment 5 of the present invention.

[0039] Figure 12 This is a graph showing the cycle coulombic efficiency and capacity retention of a coin cell prepared using LFMP material in Example 5 of the present invention.

[0040] Figure 13 This is a charge-discharge curve of a coin cell prepared using NVP material in Embodiment 6 of the present invention at 30°C.

[0041] Figure 14 This is a comparison chart of the cycle coulombic efficiency and capacity retention of the coin cell prepared using NVP material in Example 6 of the present invention at 30°C.

[0042] Figure 15 This is a charge-discharge curve of a coin cell prepared using NCM622 material in Example 7 of the present invention.

[0043] Figure 16 This is a comparison chart of the cycle coulombic efficiency and cycle capacity of the coin cells prepared using NCM622 material in Example 7 and Comparative Example 5 of the present invention. Detailed Implementation

[0044] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this invention, and not all of them. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0045] For experiments not specifically described in the examples, the procedures or conditions should be followed according to the conventional experimental procedures described in the literature in this field. Reagents or instruments whose manufacturers are not specified are all commercially available conventional reagent products.

[0046] This invention provides a method for preparing an in-situ liquefied solid-liquid hybrid battery, such as... Figure 1 As shown, the specific steps include: Step S1: Prepare a positive electrode or prepare a positive electrode containing a first deep eutectic component.

[0047] The preparation of the positive electrode specifically includes: adding the positive electrode active material, the first conductive agent, and the first binder to the first solvent in a certain proportion, mixing them evenly to form a positive electrode slurry, then coating the positive electrode slurry onto the positive electrode current collector, and obtaining the positive electrode after drying and rolling. The mass ratio of the positive electrode active material, the first conductive agent, and the first binder is 60–80:5–20:5–20, and the sum of their masses is 100.

[0048] The preparation of a cathode containing a first deep eutectic component specifically includes: coating a slurry containing a first deep eutectic component onto the surface of the cathode to obtain a cathode containing a first deep eutectic component; or mixing the first deep eutectic component into the cathode slurry, then coating the cathode slurry containing the first deep eutectic component onto the cathode current collector, and after drying and rolling, obtaining a cathode containing a first deep eutectic component.

[0049] The positive electrode active material includes one or more of the following: lithium iron phosphate, lithium manganese oxide, lithium cobalt oxide, ternary materials, polyanionic salt positive electrode materials, sodium manganese oxide, sodium nickel oxide, sodium iron oxide, sodium nickel manganate, sodium nickel iron manganate, or sodium vanadium phosphate. Among them, sodium nickel manganate includes NaNi... 0.4 Fe 0.2 Mn 0.4 O2 (Type 424); Sodium nickel iron manganate includes NaNi 1 / 3 Fe 1 / 3 Mn 1 / 3 O2 (Model 111).

[0050] The first conductive agent includes one or more of conductive carbon black, carbon nanotubes, carbon fibers, or graphene. The conductive carbon black includes one or more of Super P, acetylene black, and Ketjen black. The first binder includes one or more of polyvinylidene fluoride (PVDF), styrene-butadiene rubber (SBR), sodium carboxymethyl cellulose (CMC-Na), polyacrylic acid (PAA), polyamide (PAI), polyvinyl alcohol (PVA), polyethyleneimine (PEI), polyacrylonitrile (PAN), polyimide (PI), or polyacrylate (PAE).

[0051] The first solvent includes one or more of N-methylpyrrolidone (NMP), water, acetonitrile, acetone, or dimethylformamide (DMF).

[0052] The positive current collector includes any one of aluminum foil, carbon-coated aluminum foil, or porous aluminum foil.

[0053] The first deep eutectic component is a hydrogen bond acceptor or hydrogen bond donor.

[0054] Specifically, hydrogen bond acceptors include: lithium bis(fluorosulfonyl)imide (LiFSI), sodium bis(fluorosulfonyl)imide (NaFSI), lithium bis(trifluoromethanesulfonyl)imide (LiTFSI), sodium bis(trifluoromethanesulfonyl)imide (NaTFSI), potassium bis(trifluoromethanesulfonyl)imide (KTFSI), lithium trifluoromethanesulfonate (LiTfO), lithium trifluoroacetate (LiTFA), lithium hexafluorophosphate (LiPF6), sodium hexafluorophosphate (NaPF6), lithium difluorooxalate borate (LiDFOB), sodium difluorooxalate borate (NaDFOB), lithium chloride (LiCl), sodium chloride (NaCl), lithium bromide (LiBr), sodium bromide (NaBr), lithium iodide (LiI), sodium iodide (NaI), and lithium nitrate (LiNO3). Sodium nitrate (NaNO3), lithium perchlorate (LiClO4), sodium perchlorate (NaClO4), potassium carbonate (K2CO3), zinc bis(trifluoromethanesulfonylimide) (Zn(TFSI)2), zinc chloride (ZnCl2), zinc sulfate (ZnSO4), zinc perchlorate (Zn(ClO4)2), zinc trifluoromethanesulfonate (Zn(TfO)2), zinc tetrafluoroborate (Zn(BF4)2), zinc acetate (Zn(CH3COO)2), aluminum chloride (AlCl3), choline chloride (ChCl), choline iodide (ChI), choline bromide (ChBr), choline tetrafluoroborate (ChBF4), choline nitrate (ChNO3), choline perchlorate (ChClO4), betaine (C5H) 11 NO2), tetramethylammonium chloride (TMCl), tetraethylammonium chloride (TECl), allylmethylammonium chloride (AMCl), or tetrabutylammonium chloride (TBCl) or one or more of these.

[0055] Hydrogen bond donors include: succinic anionyl nitrile (NCCH2CH2CN), acetamide (CH3CONH2), urea (CO(NH2)2), N-methylacetamide (CH3CONHCH3), N-methylurea (NH2CONHCH3), N-ethylurea (NH2CONHCH2CH3), N,N'-dimethylurea (CH3NHCONHCH3), trifluoroacetamide (CF3CONH2), N-(3-amino-3-oxopropyl)propionamide (CH3CH2CONHCH2CH2CONH2), thiourea (CS(NH2)2), methanesulfonamide (CH3SO2NH2), N-methylmethanesulfonamide (CH3SO2NHCH3), and 2-imidazolidine. One or more of the following: ketone (C3H6N2O), glycerol (HOCH2CH(OH)CH2OH), ethylene glycol (HOCH2CH2OH), 2-hydroxypropionic acid (CH3CH(OH)COOH), oxalic acid (HOOCCOOH), N,N-dimethylacetamide (CH3CON(CH3)2), N,N,N',N'-tetramethylurea ((CH3)2NCON(CH3)2), dimethyl sulfone (CH3SO2CH3), γ-butyrolactone (C4H6O2), methyl pyruvate (CH3COCOOCH3), methyl acetoacetate (CH3COCH2COOCH3), or methyl 4-oxovalerate (CH3COCH2CH2COOCH3).

[0056] In this invention, based on the ability of methylene groups in succinate (SN) molecules to form hydrogen bonds with anions, it is defined as a hydrogen bond donor; correspondingly, salts such as lithium bis(trifluoromethanesulfonylimide) have anions that act as hydrogen bond acceptors, and are defined as hydrogen bond acceptors.

[0057] The mass of the first deep eutectic component accounts for 10% to 80% of the total mass of the cathode containing the first deep eutectic component. It can be any value within this range, such as 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, etc., but it is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0058] Step S2: Use a metal anode or prepare an anode, or prepare an anode containing a first deep eutectic component.

[0059] Metal anodes can be used directly. Metal anodes include any one of lithium metal, sodium metal, or alloy materials.

[0060] The preparation of the negative electrode specifically includes: adding the negative electrode active material, the second conductive agent, and the second binder to a second solvent in a certain proportion, mixing them evenly to form a negative electrode slurry, then coating the negative electrode slurry onto the negative electrode current collector, and obtaining the negative electrode after drying and rolling. The mass ratio of the negative electrode active material, the second conductive agent, and the second binder is 60–80:5–20:5–20, and the sum of their masses is 100.

[0061] The preparation of a negative electrode containing a first deep eutectic component specifically includes: coating a slurry containing a first deep eutectic component onto the surface of the negative electrode to obtain a negative electrode containing a first deep eutectic component; or, mixing the first deep eutectic component into a negative electrode slurry, then coating the negative electrode slurry containing the first deep eutectic component onto the negative electrode current collector, and after drying and rolling, obtaining a negative electrode containing a first deep eutectic component.

[0062] Negative electrode active materials include: artificial graphite, natural graphite, soft carbon, hard carbon, modified graphite, graphene, carbon nanotubes, Schiff base compounds, carbonyl compounds, and spinel-type lithium titanate Li4Ti5O. 12 Sodium-lithium-titanium composite oxide Na 0.66 [Li 0.22 Ti 0.78 O2, sodium tritiate Na2Ti3O7, chromium-doped sodium titanate Na 0.6 [Cr 0.6 Ti 0.4 One or more of the following: O2, sodium titanium oxyphosphate NaTiOPO4, NASICON-type sodium titanium phosphate NaTi2(PO4)3, transition metal nitrides, nano-oxides, or metal oxides.

[0063] The second conductive agent includes one or more of conductive carbon black, carbon nanotubes, carbon fibers, or graphene. Conductive carbon black includes one or more of Super P, acetylene black, and Ketjen black. The second binder includes one or more of polyvinylidene fluoride (PVDF), styrene-butadiene rubber (SBR), sodium carboxymethyl cellulose (CMC-Na), polyacrylic acid (PAA), polyamide (PAI), polyvinyl alcohol (PVA), polyethyleneimine (PEI), polyacrylonitrile (PAN), polyimide (PI), or polyacrylate (PAE).

[0064] The second solvent includes one or more of N-methylpyrrolidone (NMP), water, acetonitrile, acetone, or dimethylformamide (DMF).

[0065] Negative current collectors include: copper foil, carbon-coated copper foil, or porous copper foil.

[0066] The second deep eutectic component is either a hydrogen bond acceptor or a hydrogen bond donor, and of the first and second deep eutectic components, one is a hydrogen bond acceptor and the other is a hydrogen bond donor. The mass of the first deep eutectic component accounts for 10% to 80% of the total mass of the negative electrode containing the first deep eutectic component, and can be any value within this range, such as 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, etc., but is not limited to the listed values; other unlisted values ​​within this range are also applicable.

[0067] Specifically, hydrogen bond acceptors include: lithium bis(fluorosulfonyl)imide (LiFSI), sodium bis(fluorosulfonyl)imide (NaFSI), lithium bis(trifluoromethanesulfonyl)imide (LiTFSI), sodium bis(trifluoromethanesulfonyl)imide (NaTFSI), potassium bis(trifluoromethanesulfonyl)imide (KTFSI), lithium trifluoromethanesulfonate (LiTfO), lithium trifluoroacetate (LiTFA), lithium hexafluorophosphate (LiPF6), sodium hexafluorophosphate (NaPF6), lithium difluorooxalate borate (LiDFOB), sodium difluorooxalate borate (NaDFOB), lithium chloride (LiCl), sodium chloride (NaCl), lithium bromide (LiBr), sodium bromide (NaBr), lithium iodide (LiI), sodium iodide (NaI), and lithium nitrate (LiNO3). Sodium nitrate (NaNO3), lithium perchlorate (LiClO4), sodium perchlorate (NaClO4), potassium carbonate (K2CO3), zinc bis(trifluoromethanesulfonylimide) (Zn(TFSI)2), zinc chloride (ZnCl2), zinc sulfate (ZnSO4), zinc perchlorate (Zn(ClO4)2), zinc trifluoromethanesulfonate (Zn(TfO)2), zinc tetrafluoroborate (Zn(BF4)2), zinc acetate (Zn(CH3COO)2), aluminum chloride (AlCl3), choline chloride (ChCl), choline iodide (ChI), choline bromide (ChBr), choline tetrafluoroborate (ChBF4), choline nitrate (ChNO3), choline perchlorate (ChClO4), betaine (C5H) 11 NO2), tetramethylammonium chloride (TMCl), tetraethylammonium chloride (TECl), allylmethylammonium chloride (AMCl), or tetrabutylammonium chloride (TBCl) or one or more of these.

[0068] Hydrogen bond donors include: succinic anionyl nitrile (NCCH2CH2CN), acetamide (CH3CONH2), urea (CO(NH2)2), N-methylacetamide (CH3CONHCH3), N-methylurea (NH2CONHCH3), N-ethylurea (NH2CONHCH2CH3), N,N'-dimethylurea (CH3NHCONHCH3), trifluoroacetamide (CF3CONH2), N-(3-amino-3-oxopropyl)propionamide (CH3CH2CONHCH2CH2CONH2), thiourea (CS(NH2)2), methanesulfonamide (CH3SO2NH2), N-methylmethanesulfonamide (CH3SO2NHCH3), and 2-imidazolidine. One or more of the following: ketone (C3H6N2O), glycerol (HOCH2CH(OH)CH2OH), ethylene glycol (HOCH2CH2OH), 2-hydroxypropionic acid (CH3CH(OH)COOH), oxalic acid (HOOCCOOH), N,N-dimethylacetamide (CH3CON(CH3)2), N,N,N',N'-tetramethylurea ((CH3)2NCON(CH3)2), dimethyl sulfone (CH3SO2CH3), γ-butyrolactone (C4H6O2), methyl pyruvate (CH3COCOOCH3), methyl acetoacetate (CH3COCH2COOCH3), or methyl 4-oxovalerate (CH3COCH2CH2COOCH3).

[0069] Step S4: Prepare a first solid electrolyte membrane or a second solid electrolyte membrane containing a second deep eutectic component.

[0070] Specifically, it includes the following two methods: Method 1: Add the electrolyte material and the second deep eutectic component to a third solvent in a certain proportion, mix evenly to form an electrolyte slurry, and form a film from the electrolyte slurry by casting, scraping, or coating. Bake to remove the third solvent to obtain a solid electrolyte membrane containing the second deep eutectic component, denoted as the first solid electrolyte membrane. The mass of the second deep eutectic component accounts for 30% to 80% of the total mass of the first solid electrolyte membrane. It can be any value within this range, such as 30%, 40%, 50%, 60%, 70%, 80%, etc., but is not limited to the listed values; other unlisted values ​​within this range are also applicable.

[0071] Method 2: A second deep eutectic component capable of forming an independent film is thermally composited to form a second deep eutectic component membrane. This second deep eutectic component membrane is then composited with a separator to obtain a solid electrolyte membrane containing the second deep eutectic component, denoted as the second solid electrolyte membrane. The mass of the second deep eutectic component accounts for 70%–100% of the total mass of the second solid electrolyte membrane. The separator includes one or more of the following: polyolefin microporous separator, coated modified separator, nonwoven separator, or special separator.

[0072] The temperature for the thermal bonding treatment is 30℃ to 200℃, and can be any value within this range, such as 30℃, 50℃, 70℃, 90℃, 100℃, 150℃, 200℃, etc., but is not limited to the listed values; other unlisted values ​​within this range are also applicable. The pressure for the thermal bonding treatment is 0 to 200MPa, and can be any value within this range, such as 0MPa, 5MPa, 20MPa, 40MPa, 60MPa, 80MPa, 100MPa, 120MPa, 140MPa, 160MPa, 180MPa, 200MPa, etc., but is not limited to the listed values; other unlisted values ​​within this range are also applicable. In this invention, the pressure range of the thermal bonding process includes 0 MPa. When the pressure is 0 MPa, it means that bonding is achieved under heating conditions solely through the viscosity of the second deep eutectic component material itself, gravity, or the natural adhesion between the diaphragm and the deep eutectic component film, without applying additional external mechanical pressure. In actual operation, the second deep eutectic component film and the diaphragm can be stacked and placed in a heating environment, utilizing the surface tension and interlayer adhesion of the materials in their molten or softened states to achieve bonding, without the need for specialized pressurization equipment.

[0073] The mass ratio of the electrolyte material to the second deep eutectic component is 20–90:10–80, and can be any ratio within this range, such as 20:80, 30:70, 40:60, 50:50, 60:40, 70:30, 80:20, 90:10, etc., but is not limited to the listed ratios. Other unlisted ratios within this range are also applicable.

[0074] The electrolyte materials include: organic electrolyte materials and / or inorganic electrolyte materials; organic electrolyte materials include: polyethylene oxide (PEO), 1,3,5-trioxane (TXE), polyethylene (PP), hydroxypropyl methylcellulose (HPMC), polypropylene (PE), polybutene (PB), polyvinyl alcohol (PVA), polytetrafluoroethylene (PTFE), polyethylene glycol (PEG), polyvinylidene fluoride (PVDF), cellulose acetate phthalate (CAP), polypropylene terephthalate (PTT), hydroxypropyl methylcellulose acetate succinate (HPMCAS), polybutylene terephthalate (PBT), polyethylene terephthalate (PET), polycarbonate (PC), polyimide (PI), polyvinyl chloride (PVC), polyamide (PA), polyethersulfone (PES), polyphenylene sulfide (PPS), polyethylene naphthalate (PEN), and polyvinyl chloride. One or more of the following: polyvinyl ketone (PVP), methyl cellulose (MC), ethyl cellulose (EC), hydroxypropyl cellulose (HPC), hydroxypropyl methyl cellulose phthalate (HPMCP), sodium carboxymethyl cellulose (CMC-Na), microcrystalline cellulose (MCC), sodium carboxymethyl starch (CMS-Na), crospovidone (PVPP), crospovidone carboxymethyl cellulose (CCNa), perfluorosulfonic acid resin (Nafion), perfluorosulfonic acid ion exchange membrane, or chitin nanofibers; inorganic electrolyte materials include: LLZO, LLZTO, LATP, LLTO alumina (Al2O3), tin oxide (SnO2), zinc oxide (ZnO), aluminum phosphate (AIPO4), lithium phosphate (Li3PO4), lithium silicate (Li2SiO3), calcium silicate (CaSiO3), sulfide solid electrolyte materials, or halide solid electrolyte materials.

[0075] The third solvent includes one or more of N-methylpyrrolidone (NMP), acetonitrile, acetone, tetrahydrofuran (THF), dimethylformamide (DMF), or water.

[0076] In optional solutions, the electrolyte slurry may also include one or more of the following: salt materials and binder materials.

[0077] Salt materials include: sodium salicylate hydroquinone borate, sodium hexafluorophosphate lithium trifluoromethanesulfonate, sodium tetraphenylborate lithium difluorophosphate, sodium difluorophosphate, sodium dioxophosphate, sodium dioxophosphate borate, lithium dioxophosphate borate, lithium dioxophosphate borate, sodium di(salicylic acid-2-)borate, lithium difluorooxophosphate borate, sodium difluorooxophosphate borate, sodium 4,5-dicyano-2-(trifluoromethyl)imidazolium, lithium difluorosulfonylimide, lithium di(trifluoromethanesulfonylimide), sodium di(trifluoromethanesulfonylimide), lithium perchlorate, lithium hexafluoroarsenate, sodium perchlorate, sodium hexafluoroarsenate, sodium trifluoromethanesulfonate, lithium tetrafluoroborate, lithium hexafluorophosphate, sodium tetrafluoroborate, sodium 4,5-dicyano-2-(pentafluoroethyl)imidazolium, sodium dioxophosphate borate, sodium difluorosulfonylimide, or sodium dioxophosphate borate, or one or more of these.

[0078] The adhesive materials include one or more of the following: polyvinylidene fluoride (PVDF), styrene-butadiene rubber (SBR), sodium carboxymethyl cellulose (CMC-Na), polyacrylic acid (PAA), polyamide (PAI), polyvinyl alcohol (PVA), polyethyleneimine (PEI), polyacrylonitrile (PAN), polyimide (PI), or polyacrylate (PAE).

[0079] Step S5: The positive electrode or a positive electrode containing the first deep eutectic component, the negative electrode or a negative electrode containing the first deep eutectic component, and the solid electrolyte membrane containing the second deep eutectic component are stacked and assembled in sequence. After the assembly is completed, pressure treatment and / or heating treatment are performed to make the first deep eutectic component and the second deep eutectic component form a solid-liquid mixed state deep eutectic electrolyte in situ, so as to obtain an in-situ liquefied solid-liquid hybrid battery.

[0080] Specifically: A positive electrode containing a first deep eutectic component, a first solid electrolyte membrane or a second solid electrolyte membrane, and a negative electrode are sequentially stacked and assembled; or a positive electrode containing a first deep eutectic component, a first solid electrolyte membrane or a second solid electrolyte membrane, and a negative electrode containing a first deep eutectic component are sequentially stacked and assembled; or a positive electrode, a first solid electrolyte membrane or a second solid electrolyte membrane, and a negative electrode containing a first deep eutectic component are sequentially stacked and assembled to form a battery precursor. After pressurization and / or heating, the first and second deep eutectic components form a solid-liquid mixed state deep eutectic electrolyte in situ, resulting in an in-situ liquefied solid-liquid hybrid battery. The sequential stacking and assembly process also includes stacking a positive electrode shell, a gasket, and a negative electrode shell, in the following order: positive electrode shell, gasket, positive electrode or positive electrode containing the first deep eutectic component, first solid electrolyte membrane or second solid electrolyte membrane, negative electrode or negative electrode containing the first deep eutectic component, and negative electrode shell. Preferably, before battery assembly, the positive electrode, negative electrode, and solid electrolyte membrane are all entirely solid-state.

[0081] A schematic diagram illustrating the assembly and stacking process of the solid-liquid hybrid battery provided in this embodiment of the invention, as shown below. Figure 2 As shown, there are three examples of assembly and stacking: Figure 2 In a, the negative electrode contains a first deep eutectic component, and the solid electrolyte membrane contains a second deep eutectic component; Figure 2 In b, both the positive and negative electrodes contain a first deep eutectic component, and the solid electrolyte membrane contains a second deep eutectic component. Figure 2 In c, the negative electrode contains a first deep eutectic component, and the solid electrolyte membrane contains a second deep eutectic component.

[0082] In step S5 of this invention, no pressurization treatment may be required, or the pressure used for pressurization treatment may be greater than 0 and less than or equal to 200 MPa. It can be any value within this range, such as: 1 MPa, 10 MPa, 20 MPa, 30 MPa, 40 MPa, 50 MPa, 60 MPa, 70 MPa, 80 MPa, 90 MPa, 100 MPa, 110 MPa, 120 MPa, 130 MPa, 140 MPa, 150 MPa, 160 MPa, 170 MPa, 180 MPa, 190 MPa, 200 MPa, etc., but it is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0083] The purpose of pressurization is to create a tight physical contact between the electrode and the solid electrolyte membrane, shorten the ion transport distance, and reduce the interfacial impedance. In addition, pressure can promote full contact between the first deep eutectic component and the second deep eutectic component, accelerating the in-situ deep eutectic reaction.

[0084] The pressurization process in this invention can be instantaneous pressurization after the sequential stacking and assembly is completed, short-term pressurization, or continuous pressurization from instantaneous pressurization to continuous pressurization during the cycle.

[0085] Instantaneous pressurization involves applying pressure briefly (e.g., for a few seconds) during assembly, with no further pressure applied. Instantaneous pressurization is suitable for solid electrolyte membranes with good plasticity (e.g., PEO-based solid electrolyte membranes), where a single pressurization is sufficient to maintain good contact.

[0086] After a short period of pressurization, the pressure is maintained for several minutes to several hours after assembly, requiring a certain amount of time for the first deep eutectic component and the second deep eutectic component to fully react.

[0087] Continuous pressurization ensures good interfacial contact between the electrodes during repeated charge-discharge cycles, preventing capacity decay due to contact failure. Continuous pressurization throughout the charge-discharge cycle is suitable for systems with large volume changes (such as alloy anodes) or rigid systems with easily delaminating interfaces. The heat treatment in step S5 of this invention can be performed after stacking and assembly, during cyclic testing, or from instantaneous heating after stacking and assembly to continuous heating during cycling, depending on requirements. Preferably, the heat treatment involves allowing the electrode to stand at a set temperature for several hours after stacking and assembly to allow the deep eutectic reaction to proceed fully and form a stable interfacial contact.

[0088] The main function of heating is to reduce the viscosity of the system, promote molecular motion, and accelerate the diffusion and reaction between deep eutectic components. For polymer electrolytes such as PEO, heating above their melting point can achieve higher ionic conductivity.

[0089] The temperature for heat treatment is 25℃ to 200℃, and can be any value within this range, such as 25℃, 30℃, 40℃, 50℃, 60℃, 70℃, 80℃, 90℃, 100℃, 150℃, 200℃, etc., but is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0090] This invention provides a solid-liquid hybrid battery prepared by the above-described method, comprising: a lithium-ion solid-liquid hybrid battery or a sodium-ion solid-liquid hybrid battery.

[0091] This invention effectively solves the problems of poor interface contact, numerous side reactions, and poor consistency of traditional solid-state batteries by using in-situ liquefaction technology, thereby improving the cycle performance of the battery.

[0092] The solid-liquid hybrid battery provided in this embodiment of the invention can be applied to one or more of the following: electric vehicles, hybrid electric vehicles, electric bicycles, energy storage power stations, portable electronic devices, mobile power supplies, drones, power tools, wearable devices, medical electronic devices, aerospace vehicles, marine power systems, or grid frequency regulation energy storage systems.

[0093] To better understand the technical solution provided by the present invention, the following uses several specific examples to illustrate the preparation process and characteristics of the solid-liquid hybrid battery of the present invention.

[0094] Example 1 This embodiment provides a preparation process for a solid-liquid hybrid battery, the specific process of which is as follows.

[0095] (1) Preparation of positive electrode: The positive electrode active material lithium iron phosphate (LFP), conductive carbon black Super P, and binder polyvinylidene fluoride (PVDF) are mixed in a mass ratio of 8:1:1. N-methylpyrrolidone (NMP) is added and ground evenly to form a positive electrode slurry with a solid content of 40wt%. The slurry is coated on aluminum foil, dried, and rolled to obtain the positive electrode.

[0096] (2) A layer of the first deep eutectic component succinate (SN) is coated on the surface of the dried positive electrode by hot scraping to obtain a positive electrode containing the first deep eutectic component.

[0097] (3) A 500 μm thick lithium metal foil is used as the negative electrode.

[0098] (4) Preparation of solid electrolyte membrane: Polyethylene oxide (PEO, molecular weight 600k) and the second deep eutectic component lithium bis(trifluoromethanesulfonylimide) (LiTFSI) were dissolved in acetonitrile at a molar ratio of EO:Li = 20:1 and mixed evenly to prepare a polymer slurry with a solid concentration of 0.055 g / mL; the polymer slurry was poured into a polytetrafluoroethylene mold and baked at 55°C for 24 hours to remove acetonitrile, thus obtaining a PEO-based solid electrolyte membrane containing LiTFSI.

[0099] (5) Assembly and preparation of solid-liquid hybrid battery: In a glove box with oxygen and water content of less than 0.1 ppm, the negative electrode, the PEO-based solid electrolyte membrane containing LiTFSI, and the positive electrode containing the first deep eutectic component are stacked in sequence in the coin cell case. A pressure of 6 MPa is applied for 3 seconds using a press to make the SN on the positive electrode side contact with the LiTFSI in the PEO-based solid electrolyte membrane, forming a solid-liquid hybrid deep eutectic electrolyte in situ, and obtaining a solid-liquid hybrid battery, abbreviated as LFP (brush SN) | PEO-Li | Li.

[0100] The coulombic efficiency and cycle capacity retention of the solid-liquid hybrid battery prepared in this embodiment were tested.

[0101] The testing method was as follows: The solid-liquid hybrid battery prepared in this embodiment was placed at 70°C for 10 hours to form a stable interface contact. At 70°C, using a blue electric field tester, it was first cycled twice at a rate of 0.1C, and then subjected to a long-term charge-discharge test at a rate of 0.5C, with a voltage range of 2.5V to 4V (charging cutoff voltage was 4V, and discharging cutoff voltage was 2.5V).

[0102] Test data are detailed in Table 1.

[0103] The charge-discharge curves of LFP(brush SN)|PEO-Li|Li prepared in this embodiment at the 3rd, 50th, 100th, and 150th cycles are shown below. Figure 3As shown, the horizontal axis represents capacity (mAg / g), and the vertical axis represents voltage (V).

[0104] The coulombic efficiency and cycle capacity curves of LFP(brush SN)|PEO-Li|Li prepared in this embodiment are shown in the figure below. Figure 4 As shown, the horizontal axis represents the number of cycles, the right vertical axis represents the coulombic efficiency, and the left vertical axis represents the discharge capacity retention (DCR).

[0105] Example 2 This embodiment provides a preparation process for a solid-liquid hybrid battery. The difference from Embodiment 1 is that the positive electrode active material used is lithium nickel cobalt manganese oxide (NCM622). The other preparation processes are the same as in Embodiment 1. The specific preparation process is as follows.

[0106] (1) Preparation of positive electrode: NCM622 material, Super P and polyvinylidene fluoride (PVDF) are mixed in a mass ratio of 8:1:1, N-methylpyrrolidone (NMP) is added and ground evenly to form a positive electrode slurry with a solid content of 40wt%, which is coated on aluminum foil and then dried and rolled to obtain the positive electrode.

[0107] (2) A layer of the first deep eutectic component succinate (SN) is coated on the surface of the dried positive electrode by hot scraping to obtain a positive electrode containing the first deep eutectic component.

[0108] (3) Similar to Example 1, a 500 μm thick lithium metal foil was used as the negative electrode.

[0109] (4) The process of preparing the solid electrolyte membrane is the same as in Example 1.

[0110] (5) The assembly and preparation process of the solid-liquid hybrid battery is the same as in Example 1. The resulting solid-liquid hybrid battery is referred to as 622(Brush SN)|PEO-Li|Li.

[0111] The coulombic efficiency and cycle capacity retention of the solid-liquid hybrid battery prepared in this embodiment were tested.

[0112] The test method is the same as in Example 1, with a voltage range of 2.8V to 4.3V.

[0113] Test data are detailed in Table 1.

[0114] The charge-discharge curves of the 622(brush SN)|PEO-Li|Li prepared in this embodiment at the 3rd, 50th, 100th, and 150th cycles are shown below. Figure 5 As shown.

[0115] The coulombic efficiency and cycle capacity curves of 622(brush SN)|PEO-Li|Li prepared in this embodiment are shown in the figure below. Figure 6 As shown.

[0116] Example 3 This embodiment provides a preparation process for a solid-liquid hybrid battery. The difference from Embodiment 1 is that the positive electrode active material is lithium manganese iron phosphate (LFMP), and the first deep eutectic component, succinic acid, is not coated on the positive electrode surface, but is mixed in the positive electrode slurry. The specific preparation process is as follows.

[0117] (1) Preparation of positive electrode sheet containing the first deep eutectic component: The positive electrode active material LFMP, Super P, polyvinylidene fluoride (PVDF) and succinic acid (SN) are mixed in a mass ratio of 7:1:1:1. N-methylpyrrolidone (NMP) is added and ground evenly to form a positive electrode slurry with a solid content of 40wt%. The slurry is coated on aluminum foil, dried and rolled to obtain a positive electrode containing the first deep eutectic component.

[0118] (2) A 300 μm thick lithium metal foil was used as the negative electrode, the same as in Example 1.

[0119] (3) The process of preparing the solid electrolyte membrane is the same as in Example 1.

[0120] (4) The assembly and preparation process of the solid-liquid hybrid battery is the same as in Example 1: In a glove box with oxygen and water content of less than 0.1 ppm, the negative electrode, the PEO-based solid electrolyte membrane containing LiTFSI, and the positive electrode containing the first deep eutectic component are stacked in sequence in the coin cell case. A pressure of 6 MPa is applied for 3 seconds using a press. The SN on the positive electrode side comes into contact with the LiTFSI in the PEO-based solid electrolyte membrane, and a solid-liquid hybrid deep eutectic electrolyte is formed in situ, thus obtaining the solid-liquid hybrid battery, abbreviated as LFMP (SN)|PEO-Li|Li.

[0121] The coulombic efficiency and cycle capacity retention of the solid-liquid hybrid battery prepared in this embodiment were tested.

[0122] The test method is the same as in Example 1, with a voltage range of 2.5V to 4.3V.

[0123] Test data are detailed in Table 1.

[0124] The charge-discharge curves of LFMP (SN)|PEO-Li|Li prepared in this embodiment at the 3rd, 50th, 100th, and 150th cycles are shown below. Figure 7 As shown.

[0125] The coulombic efficiency and cycle capacity curves of LFMP (SN)|PEO-Li|Li prepared in this embodiment are shown in the figure below. Figure 8 As shown, the horizontal axis represents the number of cycles, the right vertical axis represents the Coulombic efficiency, and the left vertical axis represents the cycle capacity.

[0126] Example 4 This embodiment provides a preparation process for a solid-liquid hybrid battery. The difference from Embodiment 1 is that the electrolyte material in the solid electrolyte membrane is different. The specific process is as follows.

[0127] (1) Preparation of positive electrode: The positive electrode active material lithium iron phosphate (LFP), conductive carbon black Super P, and binder polyvinylidene fluoride (PVDF) are mixed in a mass ratio of 8:1:1. N-methylpyrrolidone (NMP) is added and ground evenly to form a positive electrode slurry with a solid content of 40wt%. The slurry is coated on aluminum foil, dried, and rolled to obtain the positive electrode.

[0128] (2) A layer of the first deep eutectic component succinate (SN) is coated on the surface of the dried positive electrode by hot scraping to obtain a positive electrode containing the first deep eutectic component.

[0129] (3) A 300 μm thick lithium metal foil is used as the negative electrode.

[0130] (4) Preparation of solid electrolyte membrane: 1,3,5-trioxane (TXE) (2g), LiTFSI (0.73g) and PVDF (0.8g) were dissolved in 6ml of N-methylpyrrolidone (NMP). After stirring evenly with a high-speed mixer, the mixture was coated onto aluminum foil with a 500-micron thick scraper and dried until NMP was completely evaporated to obtain TXE-based solid electrolyte membrane.

[0131] (5) Assembly and preparation of solid-liquid hybrid battery: In a glove box with oxygen and water content of less than 0.1 ppm, the negative electrode, the TXE-based solid electrolyte membrane containing LiTFSI, and the positive electrode containing the first deep eutectic component are stacked in sequence in the coin cell case. A pressure of 6 MPa is applied for 3 seconds using a press. The SN on the positive electrode side comes into contact with the LiTFSI in the TXE-based solid electrolyte membrane, and a solid-liquid hybrid state deep eutectic electrolyte is formed in situ, thus obtaining a solid-liquid hybrid battery, abbreviated as LFP (brush SN) | TXE-Li | Li.

[0132] The coulombic efficiency and cycle capacity retention of the solid-liquid hybrid battery prepared in this embodiment were tested.

[0133] The testing method was as follows: the solid-liquid hybrid battery prepared in this embodiment was left to stand at 30°C for 10 hours to form a stable interface contact. At 30°C, a long-cycle charge-discharge test was conducted using a blue electric field tester at a rate of 0.1C, with a voltage range of 2.5V to 4V.

[0134] Test data are detailed in Table 1.

[0135] The charge-discharge curves of LFP(brush SN)|TXE-Li|Li prepared in this embodiment at the 3rd, 50th, 100th, and 150th cycles are shown below. Figure 9 As shown.

[0136] The coulombic efficiency and cycle capacity curves of LFP(brush SN)|TXE-Li|Li prepared in this embodiment are shown in the figure below. Figure 10 As shown.

[0137] Example 5 This embodiment provides a preparation process for a solid-liquid hybrid battery. The difference from Embodiment 4 is that the positive electrode active material used is lithium manganese iron phosphate (LFMP). The other preparation processes are the same as in Embodiment 4. The specific process is as follows.

[0138] (1) Preparation of positive electrode: Lithium iron manganese phosphate (LFMP), conductive carbon black Super P, and binder polyvinylidene fluoride (PVDF) are mixed in a mass ratio of 8:1:1. N-methylpyrrolidone (NMP) is added and ground evenly to form a positive electrode slurry with a solid content of 40wt%. The slurry is coated on aluminum foil, dried, and rolled to obtain the positive electrode.

[0139] (2) A layer of the first deep eutectic component succinate (SN) is coated on the surface of the dried positive electrode by hot scraping to obtain a positive electrode containing the first deep eutectic component.

[0140] (3) A 300 μm thick lithium metal foil is used as the negative electrode.

[0141] (4) Preparation of solid electrolyte membrane: 1,3,5-trioxane (TXE) (2g), LiTFSI (0.73g) and PVDF (0.8g) were dissolved in 6ml of N-methylpyrrolidone (NMP). After stirring evenly with a high-speed mixer, the mixture was coated onto aluminum foil with a 500-micron thick scraper and dried until NMP was completely evaporated to obtain TXE-based solid electrolyte membrane.

[0142] (5) Assembly and preparation of solid-liquid hybrid battery: In a glove box with oxygen and water content of less than 0.1 ppm, the negative electrode, the TXE-based solid electrolyte membrane containing LiTFSI, and the positive electrode containing the first deep eutectic component are stacked in sequence in the coin cell case. A pressure of 6 MPa is applied for 3 seconds using a press. The SN on the positive electrode side comes into contact with the LiTFSI in the TXE-based solid electrolyte membrane, and a solid-liquid hybrid state deep eutectic electrolyte is formed in situ, resulting in a solid-liquid hybrid battery, abbreviated as LFMP (brushed SN)|TXE-Li|Li.

[0143] The coulombic efficiency and cycle capacity retention of the solid-liquid hybrid battery prepared in this embodiment were tested.

[0144] The test method is the same as in Example 4, with a voltage range of 2.5V to 4.3V.

[0145] Test data are detailed in Table 1.

[0146] The charge-discharge curves of LFMP (brush SN)|TXE-Li|Li prepared in this embodiment at the 3rd, 50th, 100th, and 150th cycles are shown below. Figure 11 As shown.

[0147] The coulombic efficiency and cycle capacity curves of LFMP (brush SN)|TXE-Li|Li prepared in this embodiment are shown in the figure below. Figure 12 As shown.

[0148] Example 6 This embodiment provides a preparation process for a solid-liquid hybrid battery. The difference from Embodiment 1 is that the positive electrode active material is sodium vanadium phosphate (NVP), and a sodium-ion solid-liquid hybrid battery is prepared. The specific process is as follows.

[0149] (1) Preparation of positive electrode: Sodium vanadium phosphate (NVP), conductive carbon black Super P, binder polyvinylidene fluoride (PVDF), 1,3,2-dioxane-2,2-dioxide (PCS) are mixed in a mass ratio of 7:1:1:1, N-methylpyrrolidone (NMP) is added and ground evenly to form a positive electrode slurry with a solid content of 40wt%, which is coated on aluminum foil, dried and rolled to obtain a positive electrode containing the first deep eutectic component.

[0150] (2) A 300 μm thick sodium metal sheet is used as the negative electrode.

[0151] (3) Preparation of solid electrolyte membrane: Polyethylene oxide (PEO, molecular weight: 600K) and NaFSI are prepared in acetonitrile at a molar ratio of EO:Na=20:1 to form a solid substance concentration of 0.055g / ml. The mixture is stirred evenly to obtain a polymer slurry. The polymer slurry is poured onto a polytetrafluoroethylene mold and dried in acetonitrile to obtain a PEO-based polymer solid electrolyte membrane.

[0152] (4) Assembly and preparation of solid-liquid hybrid battery: In a glove box with oxygen and water content of less than 0.1 ppm, the negative electrode, the PEO-based solid electrolyte membrane containing NaFSI, and the positive electrode containing the first deep eutectic component are stacked in sequence in the coin cell case. A pressure of 6 MPa is applied for 3 seconds using a press. The PCS on the positive electrode side comes into contact with the NaFSI in the PEO-based solid electrolyte membrane, and a solid-liquid hybrid state deep eutectic electrolyte is formed in situ, resulting in a solid-liquid hybrid battery, abbreviated as NVP(PCS)|PEO-Na|Na.

[0153] The coulombic efficiency and cycle capacity retention of the solid-liquid hybrid battery prepared in this embodiment were tested.

[0154] The testing method is as follows: First, the solid-liquid hybrid battery prepared in this embodiment is placed at 70°C for 10 hours to form a stable interface contact. Then, at 30°C, a long-cycle charge-discharge test is performed using a blue electric field tester at a rate of 0.1C, with a voltage range of 2.5V to 4V.

[0155] Test data are detailed in Table 1.

[0156] The charge-discharge curves of NVP(PCS)|PEO-Na|Na prepared in this embodiment at cycles 3, 50, 100, and 150 are shown below. Figure 13 As shown.

[0157] The coulombic efficiency and cycle capacity curves of NVP(PCS)|PEO-Na|Na prepared in this embodiment are shown in the figure below. Figure 14 As shown.

[0158] Example 7 This embodiment provides a preparation process for a solid-liquid hybrid battery. The difference from Embodiment 2 is that the first deep eutectic component is different, and PCS is used. Furthermore, the PCS is not coated on the surface of the positive electrode, but is mixed in the positive electrode slurry. In addition, the electrolyte material in the solid electrolyte membrane is also different. The specific process is as follows.

[0159] (1) Preparation of positive electrode: NCM622 material, conductive carbon black Super P, binder polyvinylidene fluoride (PVDF) and 1,3,2-dioxane-2,2-dioxide (PCS) are mixed in a mass ratio of 7:1:1:1. N-methylpyrrolidone (NMP) is added and ground evenly to form a positive electrode slurry with a solid content of 40wt%. The slurry is coated on aluminum foil and then dried and rolled to obtain a positive electrode containing the first deep eutectic component.

[0160] (2) A 300μm thick lithium metal sheet is used as the negative electrode.

[0161] (3) Preparation of solid electrolyte membrane: Block polymer (BCP) and lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) are dissolved in acetonitrile at a molar ratio of EO:Li=20:1 and mixed evenly to prepare a polymer slurry with a solid concentration of 0.055 g / mL; The polymer slurry is poured into a polytetrafluoroethylene mold and baked to remove acetonitrile to obtain a BCP-based solid electrolyte membrane containing LiTFSI.

[0162] (4) Assembly and preparation of solid-liquid hybrid battery: In a glove box with oxygen and water content of less than 0.1 ppm, the negative electrode, the BCP-based solid electrolyte membrane containing LiTFSI, and the positive electrode containing the first deep eutectic component are stacked in sequence in the coin cell case. A pressure of 6 MPa is applied for 3 seconds using a press. The PCS on the positive electrode side comes into contact with the LiTFSI in the BCP-based solid electrolyte membrane, and a solid-liquid hybrid state deep eutectic electrolyte is formed in situ, resulting in a solid-liquid hybrid battery, abbreviated as 622(PCS)|BCP-Li|Li.

[0163] The coulombic efficiency and cycle capacity retention of the solid-liquid hybrid battery prepared in this embodiment were tested.

[0164] The testing method was as follows: the solid-liquid hybrid battery prepared in this embodiment was left to stand at 70°C for 10 hours to form a stable interface contact. At 30°C, a long-cycle charge-discharge test was conducted using a blue electric field tester at a rate of 0.1C, with a voltage range of 2.8V to 4.3V.

[0165] Test data are detailed in Table 1.

[0166] The charge-discharge curves of 622(PCS)|BCP-Li|Li prepared in this embodiment at the 3rd, 50th, 100th, and 150th cycles are shown below. Figure 15 As shown.

[0167] The coulombic efficiency and cycle capacity curves of 622(PCS)|BCP-Li|Li prepared in this embodiment are shown in the figure below. Figure 16 As shown.

[0168] To better illustrate the effects of the embodiments of the present invention, the following comparative examples are compared with the embodiments described above.

[0169] Comparative Example 1 The difference between this comparative example and Example 1 is that the first deep eutectic component is not introduced into the positive electrode, that is, the step (2) of hot scraping and coating succinate (SN) on the surface of the dried positive electrode is removed. The remaining steps are the same, and the resulting battery is referred to as LFP (without SN)|PEO-Li|Li.

[0170] The coulombic efficiency and cycle capacity retention of the LFP (without SN)|PEO-Li|Li battery prepared in this comparative example were tested. The test method was the same as in Example 1, and the test data are detailed in Table 1.

[0171] The coulombic efficiency and cycle capacity curves of the LFP (without SN)|PEO-Li|Li battery prepared in this comparative example are shown in the figure. Figure 4 As shown. (Through) Figure 4As can be seen, the battery LFP (without SN)|PEO-Li|Li after introducing the first deep eutectic component in Example 1 retains approximately 82.09% capacity after 200 cycles, exhibiting good cycle stability and slow capacity decay. In contrast, the battery LFP (without SN)|PEO-Li|Li in Comparative Example 1, without the eutectic component, retains less than 60% capacity (specifically 58.95%) after only 180 cycles, showing rapid capacity decay and a short cycle life. This demonstrates that the preparation method provided in this embodiment can effectively improve the cycle life and capacity retention of solid-liquid hybrid batteries.

[0172] Comparative Example 2 The difference between this comparative example and Example 2 is that the first deep eutectic component is not introduced into the positive electrode, that is, the step of hot scraping and coating succinate (SN) on the surface of the dried positive electrode sheet in step (2) is removed. All other steps are the same, and the resulting battery is referred to as 622 (without SN) |PEO-Li|Li.

[0173] The coulombic efficiency and cycle capacity retention of the 622 (without SN)|PEO-Li|Li battery prepared in this comparative example were tested. The test method was the same as in Example 2, and the test data are detailed in Table 1.

[0174] The coulombic efficiency and cycle capacity curves of the 622 (without SN)|PEO-Li|Li battery prepared in this comparative example are shown in the figure. Figure 6 As shown. (Through) Figure 6 As can be seen, the capacity retention rate of the battery 622 (with SN) | PEO-Li | Li after 200 cycles in Example 1, after introducing the first deep eutectic component, is about 43.7%; while the capacity retention rate of the battery 622 (without SN) | PEO-Li | Li in Comparative Example 2, which does not use the eutectic component, is 42.86%.

[0175] Comparative Example 3 The difference between this comparative example and Example 3 is that step (1) does not add the first deep eutectic component succinate, but instead adds PEO. Specifically, the positive electrode active material LFMP, Super P, polyvinylidene fluoride (PVDF) and polyoxyethylene (PEO) are mixed in a mass ratio of 7:1:1:1, N-methylpyrrolidone (NMP) is added and ground evenly to form a positive electrode slurry with a solid content of 40wt%, which is coated on aluminum foil and then dried and rolled to obtain the positive electrode. The other steps are the same as in Example 3. The battery obtained is referred to as LFMP (PEO)|PEO-Li|Li.

[0176] The coulombic efficiency and cycle capacity retention of the LFMP (PEO)|PEO-Li|Li battery prepared in this comparative example were tested. The test method was the same as in Example 3, and the test data are detailed in Table 1.

[0177] The coulombic efficiency and cycle capacity curves of the LFMP (PEO)|PEO-Li|Li battery prepared in this comparative example are shown in the figure. Figure 8 As shown. (Through) Figure 8 As can be seen, the battery LFMP(SN)|PEO-Li|Li with the first deep eutectic component added in Example 3 retained 64.56% of its capacity after 150 cycles; while the battery LFMP(PEO)|PEO-Li|Li without the eutectic component in Comparison 3 had a lower capacity retention after 150 cycles than the battery LFMP(SN)|PEO-Li|Li. Furthermore, during cycling, the capacity of the battery LFMP(SN)|PEO-Li|Li with the first deep eutectic component added in Example 3 remained consistently higher than that of the battery without the eutectic component, and no significant capacity decay was observed. This demonstrates that the preparation method provided by this invention can effectively improve the cycle stability and cycle life of the battery.

[0178] Comparative Example 4 The difference between this comparative example and Example 6 is that the first deep eutectic component was not introduced into the positive electrode. The positive electrode preparation process was modified as follows: sodium vanadium phosphate (NVP), conductive carbon black Super P, and binder polyvinylidene fluoride (PVDF) were mixed in a mass ratio of 7:1:2, N-methylpyrrolidone (NMP) was added and ground evenly to form a positive electrode slurry with a solid content of 40wt%. The slurry was coated on aluminum foil, dried, and rolled to obtain the positive electrode. The other preparation processes were the same as in Example 6. The resulting battery was abbreviated as NVP (without PCS)|PEO-Na|Na.

[0179] The coulombic efficiency and cycle capacity retention of the NVP (PCS-free)|PEO-Na|Na battery prepared in this comparative example were tested. The test method was the same as in Example 6, and the test data are detailed in Table 1. The NVP (PCS-free)|PEO-Na|Na battery prepared in Comparative Example 4 could not be charged and discharged normally after assembly. This was because the interfacial impedance between the positive electrode and the solid electrolyte membrane was too high, and an abnormal voltage appeared during the first charge, making it impossible to form an effective charge-discharge cycle. Therefore, no recordable cycle data was obtained. This result shows that without the introduction of the first deep eutectic component PCS, a good ion conduction interface cannot be formed between the PEO / NaFSI solid electrolyte and the NVP positive electrode, and the battery cannot work normally. This further proves that the introduction of the first deep eutectic component in this invention is the key to the smooth operation of the battery.

[0180] Comparative Example 5 The difference between this comparative example and Example 7 is that step (1) does not add the first deep eutectic component PCS, but instead adds a block polymer (BCP). Specifically, NCM622 material, conductive carbon black Super P, binder polyvinylidene fluoride (PVDF), and block polymer (BCP) are mixed in a mass ratio of 7:1:1:1, N-methylpyrrolidone (NMP) is added and ground evenly to form a positive electrode slurry with a solid content of 40wt%, which is coated on aluminum foil and then dried and rolled to obtain the positive electrode. The other steps are the same as in Example 7, and the resulting battery is abbreviated as 622(BCP)|BCP-Li|Li.

[0181] The coulombic efficiency and cycle capacity retention of the 622(BCP)|BCP-Li|Li battery prepared in this comparative example were tested. The test method was the same as in Example 7, and the test data are detailed in Table 1.

[0182] The coulombic efficiency and cycle capacity curves of the 622(BCP)|BCP-Li|Li battery prepared in this comparative example are shown in the figure. Figure 16 As shown. (Through) Figure 16 As can be seen, in the test comparison between the 622(BCP)|BCP-Li|Li battery of Example 7 and the 622(BCP)|BCP-Li|Li battery of Comparative Example 5, although the capacity retention rate of Example 7 after 70 cycles was slightly lower than that of Comparative Example 5, the actual discharge capacity of Example 7 was consistently higher than that of Comparative Example 5 throughout the entire cycle. This is because the PCS deep eutectic component introduced in Example 7 effectively improved the initial interface contact, allowing more active materials to participate in the reaction, thereby achieving higher initial capacity and absolute capacity. Comparative Example 5, lacking an effective deep eutectic interface, had a lower initial capacity, and although its relative retention rate was higher, its absolute capacity remained at a low level. This result demonstrates that the core advantage of this invention lies in improving the actual capacity utilization of the battery, rather than simply pursuing capacity retention rate. This invention can improve cycle stability while maintaining a high initial capacity.

[0183] Table 1 summarizes the test data for Examples 1-7 and Comparative Examples 1-5.

[0184] Table 1 The test data in Table 1 shows that: Compared to Example 1 and Comparative Example 1, in the LFP system, the capacity retention rate after 200 cycles increased from 58.95% to 82.09% after introducing SN, an improvement of approximately 23 percentage points. Compared to Example 3 and Comparative Example 3, in the LFMP system, the capacity retention rate after 150 cycles increased from 45.00% to 64.65% after introducing SN, an improvement of approximately 20 percentage points. Compared to Example 6 and Comparative Example 4, in the NVP sodium battery system, the battery with PCS introduced could cycle normally for 300 cycles with a retention rate as high as 96.42%, while the battery of Comparative Example 4 without PCS was completely inoperable. The above comparisons fully demonstrate that the introduction of the first deep eutectic component is the key to improving the electrode-electrolyte interface contact and enhancing cycle life.

[0185] Examples 1 (LFP), 2 (NCM622), and 3 (LFMP) all successfully fabricated in-situ liquefied solid-liquid hybrid batteries using different cathode materials. Examples 4 and 5 used TXE-based solid electrolyte membranes, which functioned normally at a low temperature of 30°C (coulombic efficiencies of 100% and 98.33%, respectively), while traditional PEO-based electrolytes typically require 70°C to function normally. This demonstrates that the preparation method provided in these examples can effectively reduce the battery's operating temperature. Example 6 used a sodium-ion battery system (NVP cathode, PEO / NaFSI electrolyte), also achieving an excellent retention rate of 96.42% after 300 cycles, indicating that the preparation method provided in this invention is also applicable to sodium-ion solid-liquid hybrid batteries.

[0186] Examples 1 and 2 employed a method of coating SN onto the positive electrode surface, Example 3 employed a method of directly mixing SN into the positive electrode slurry, and Examples 6 and 7 employed a method of mixing PCS into the positive electrode slurry. All these methods successfully achieved in-situ formation of deep eutectic electrolytes. This demonstrates that the preparation method provided by this invention allows for flexible selection of the introduction method of deep eutectic components according to actual process requirements, facilitating large-scale production.

[0187] The coulombic efficiencies of Examples 1-7 ranged from 97.48% to 100.18%, while those of Comparative Examples 1-3 ranged from 95.65% to 98.65%. This indicates that the in-situ formed deep eutectic electrolyte effectively suppressed interfacial side reactions and improved charge-discharge reversibility.

[0188] In summary, the process protected by this invention can be applied to various electrode and electrolyte materials, exhibiting high compatibility, simple operation, and good consistency. Because this process eliminates side reactions and residues, it effectively improves the battery's cycle capacity retention (Example 1 vs. Comparative Example 1, Example 2 vs. Comparative Example 2), enhances long-cycle stability, effectively addresses interface contact issues in solid-state batteries, and effectively increases battery capacity utilization (Example 3 vs. Comparative Example 3, Example 5 vs. Comparative Example 5) or reduces operating temperature (Example 4 vs. Comparative Example 4). This invention overcomes the shortcomings of existing in-situ solidification methods, such as residual side reactions, poor consistency, complex processes, and difficulty in gas removal. It provides a stable, controllable, consistent, easily scalable, and highly safe solid-liquid hybrid battery and its preparation method.

[0189] In summary, the preparation method protected by this invention has good versatility, applicable to various electrode and electrolyte material systems, high compatibility, and is simple to operate with good consistency. Because the solid-liquid hybrid battery prepared by this method avoids side reactions and has no residual reactants, it effectively improves the battery's cycle capacity retention rate (as shown in Examples 1 and 1, and Examples 2 and 2), significantly enhances the battery's long-cycle stability, and improves the interface contact problem of solid-state batteries. Furthermore, this process can effectively improve the battery's capacity utilization (as shown in Examples 3 and 3, and Examples 5 and 5) or reduce the operating temperature (as shown in Examples 4 and 4). Therefore, this invention overcomes the shortcomings of existing in-situ solidification methods, such as residual side reactions, poor consistency, complex processes, and difficulty in gas removal, providing a stable, controllable, consistent, easily scalable, and safe solid-liquid hybrid battery and its preparation method.

[0190] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above description is only a specific embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for preparing an in-situ liquefied solid-liquid hybrid battery, characterized in that, The preparation method includes: Step S1, preparing the positive electrode, includes: adding the positive electrode active material, the first conductive agent, and the first binder to the first solvent in proportion, mixing them evenly to form a positive electrode slurry, then coating the positive electrode slurry onto the positive electrode current collector, and obtaining the positive electrode after drying and rolling. Step S2, using a metal negative electrode or preparing a negative electrode, wherein preparing a negative electrode includes: adding a negative electrode active material, a second conductive agent, and a second binder to a second solvent in proportion, mixing them evenly to form a negative electrode slurry, then coating the negative electrode slurry onto a negative electrode current collector, and obtaining a negative electrode after drying and rolling. Step S3: Coat the surface of the positive electrode and / or the negative electrode with a slurry containing the first deep eutectic component to obtain a positive electrode containing the first deep eutectic component and / or a negative electrode containing the first deep eutectic component; or, mix the first deep eutectic component into the positive electrode slurry of step S1 and / or the negative electrode slurry of step S2 to obtain a positive electrode containing the first deep eutectic component and / or a negative electrode containing the first deep eutectic component. Step S4, preparing a first solid electrolyte membrane or a second solid electrolyte membrane containing a second deep eutectic component, including any of the following methods: Method 1: Add the electrolyte material and the second deep eutectic component to the third solvent in a certain proportion, mix them evenly to form an electrolyte slurry, form the electrolyte slurry into a film by casting, scraping, or coating, and bake to remove the third solvent to obtain the first solid electrolyte film. Method 2: The second deep eutectic component, which can form a film independently, is thermally composited to form a second deep eutectic component film. The second deep eutectic component film is then composited with a separator to obtain the second solid electrolyte film. Step S5: The positive electrode or the positive electrode containing the first deep eutectic component, the first solid electrolyte membrane or the second solid electrolyte membrane, and the negative electrode or the negative electrode containing the first deep eutectic component are stacked and assembled in sequence. After assembly, pressure treatment and / or heating treatment are performed to form a deep eutectic electrolyte in a solid-liquid mixed state between the first deep eutectic component and the second deep eutectic component in situ, thereby obtaining an in-situ liquefied solid-liquid hybrid battery.

2. The preparation method according to claim 1, characterized in that, In the first deep eutectic component and the second deep eutectic component, one is a hydrogen bond acceptor and the other is a hydrogen bond donor; The hydrogen bond acceptors include one or more of the following: lithium bis(fluorosulfonyl)imide, sodium bis(fluorosulfonyl)imide, lithium bis(trifluoromethanesulfonyl)imide, sodium bis(trifluoromethanesulfonyl)imide, potassium bis(trifluoromethanesulfonyl)imide, lithium trifluoromethanesulfonate, lithium trifluoroacetate, lithium hexafluorophosphate, sodium hexafluorophosphate, lithium difluorooxalate borate, sodium difluorooxalate borate, lithium chloride, sodium chloride, lithium bromide, sodium bromide, lithium iodide, sodium iodide, lithium nitrate, sodium nitrate, lithium perchlorate, sodium perchlorate, potassium carbonate, zinc bis(trifluoromethanesulfonyl)imide, zinc chloride, zinc sulfate, zinc perchlorate, zinc trifluoromethanesulfonate, zinc tetrafluoroborate, zinc acetate, aluminum chloride, choline chloride, choline iodide, choline bromide, choline tetrafluoroborate, choline nitrate, choline perchlorate, betaine, tetramethylammonium chloride, tetraethylammonium chloride, allylmethylammonium chloride, or tetrabutylammonium chloride. The hydrogen bond donors include one or more of the following: succinate, acetamide, urea, N-methylacetamide, N-methylurea, N-ethylurea, N,N'-dimethylurea, trifluoroacetamide, N-(3-amino-3-oxopropyl)propionamide, thiourea, methanesulfonamide, N-methylmethanesulfonamide, 2-imidazolidineone, glycerol, ethylene glycol, 2-hydroxypropionic acid, oxalic acid, N,N-dimethylacetamide, N,N,N',N'-tetramethylurea, dimethyl sulfone, γ-butyrolactone, methyl pyruvate, methyl acetoacetate, or methyl 4-oxovalerate.

3. The preparation method according to claim 1, characterized in that, The mass of the first deep eutectic component accounts for 10% to 80% of the total mass of the cathode containing the first deep eutectic component; The mass of the first deep eutectic component accounts for 10% to 80% of the total mass of the negative electrode containing the first deep eutectic component; The mass of the second deep eutectic component accounts for 30% to 80% of the total mass of the first solid electrolyte membrane; The mass of the second deep eutectic component accounts for 70% to 100% of the total mass of the second solid electrolyte membrane.

4. The preparation method according to claim 1, characterized in that, The mass ratio of the positive electrode active material, the first conductive agent, and the first binder is 60-80:5-20:5-20; The positive electrode active material includes one or more of the following: lithium iron phosphate, lithium manganese oxide, lithium cobalt oxide, ternary materials, polyanionic salt positive electrode materials, sodium manganese oxide, sodium nickel oxide, sodium iron oxide, sodium nickel manganate, sodium nickel iron manganate, or sodium vanadium phosphate. The first conductive agent includes one or more of conductive carbon black, carbon nanotubes, carbon fibers, or graphene. The first adhesive comprises one or more of the following: polyvinylidene fluoride, styrene-butadiene rubber, sodium carboxymethyl cellulose, polyacrylic acid, polyamide, polyvinyl alcohol, polyethyleneimine, polyacrylonitrile, polyimide, or polyacrylate; The first solvent includes one or more of N-methylpyrrolidone, water, acetonitrile, acetone, or dimethylformamide; The positive current collector includes: aluminum foil, carbon-coated aluminum foil, or porous aluminum foil.

5. The preparation method according to claim 1, characterized in that, In step S2, the mass ratio of the negative electrode active material, the second conductive agent, and the second binder is 60-80: 5-20: 5-20. The metal anode includes any one of lithium metal, sodium metal, or alloy materials. The negative electrode active material includes one or more of the following: artificial graphite, natural graphite, soft carbon, hard carbon, modified graphite, graphene, carbon nanotubes, Schiff base compounds, carbonyl compounds, spinel-type lithium titanate, sodium lithium titanium composite oxide, sodium tritiate, chromium-doped sodium titanate, sodium oxytitanium phosphate, NASICON-type sodium titanium phosphate, transition metal nitrides, nano-oxides, or metal oxides. The second conductive agent includes one or more of conductive carbon black, carbon nanotubes, carbon fibers, or graphene. The second adhesive comprises one or more of the following: polyvinylidene fluoride, styrene-butadiene rubber, sodium carboxymethyl cellulose, polyacrylic acid, polyamide, polyvinyl alcohol, polyethyleneimine, polyacrylonitrile, polyimide, or polyacrylate; the second solvent comprises one or more of the following: N-methylpyrrolidone, water, acetonitrile, acetone, or dimethylformamide. The negative electrode current collector includes: copper foil, carbon-coated copper foil, or porous copper foil.

6. The preparation method according to claim 1, characterized in that, In step S4, the mass ratio of the electrolyte material to the second deep eutectic component is 20-90:10-80. The electrolyte material includes: organic electrolyte materials and / or inorganic electrolyte materials; the organic electrolyte material includes: polyethylene oxide, 1,3,5-trioxane, polyethylene, hydroxypropyl methylcellulose, polypropylene, polybutene, polyvinyl alcohol, polytetrafluoroethylene, polyethylene glycol, polyvinylidene fluoride, cellulose acetate phthalate, polypropylene terephthalate, hydroxypropyl methylcellulose acetate succinate, polybutylene terephthalate, polyethylene terephthalate, polycarbonate, polyimide, polyvinyl chloride, polyamide, polyethersulfone, polyphenylene sulfide, and polyethylene naphthalate. The inorganic electrolyte material comprises one or more of the following: povidone, methylcellulose, ethylcellulose, hydroxypropylcellulose, hydroxypropyl methylcellulose phthalate, sodium carboxymethylcellulose, microcrystalline cellulose, sodium carboxymethyl starch, croscarmellose, croscarmellose sodium carboxymethylcellulose, perfluorosulfonic acid resin, perfluorosulfonic acid ion exchange membrane, or chitin nanofibers; the inorganic electrolyte material comprises one or more of the following: LLZO, LLZTO, LATP, LLTO, alumina, tin oxide, zinc oxide, aluminum phosphate, lithium phosphate, lithium silicate, calcium silicate, sulfide solid electrolyte material, or halide solid electrolyte material. The third solvent includes one or more of N-methylpyrrolidone, acetonitrile, acetone, tetrahydrofuran, dimethylformamide, or water; The electrolyte slurry further includes one or more of the following: salt materials and binder materials; the temperature of the thermal composite treatment is 30℃~200℃, and the pressure is 0~200MPa; The diaphragm includes one or more of the following: polyolefin microporous diaphragm, coated modified diaphragm, nonwoven fabric diaphragm, or special diaphragm.

7. The preparation method according to claim 6, characterized in that, The salt materials include: sodium salicylate hydroquinone borate, sodium hexafluorophosphate lithium trifluoromethanesulfonate, sodium tetraphenylborate lithium difluorophosphate, sodium difluorophosphate, sodium dioxophosphate, sodium dioxophosphate borate, lithium dioxophosphate borate, lithium dioxophosphate borate, lithium dioxophosphate borate, sodium bis(salicylic acid-2-)borate, lithium difluorooxophosphate borate, sodium difluorooxophosphate borate, sodium 4,5-dicyano-2-(trifluoromethyl)imidazolium, lithium difluorosulfonylimide, lithium di(trifluoromethanesulfonylimide), sodium di(trifluoromethanesulfonylimide), lithium perchlorate, lithium hexafluoroarsenate, sodium perchlorate, sodium hexafluoroarsenate, sodium trifluoromethanesulfonate, lithium tetrafluoroborate, lithium hexafluorophosphate, sodium tetrafluoroborate, sodium 4,5-dicyano-2-(pentafluoroethyl)imidazolium, sodium dioxophosphate borate, sodium difluorosulfonylimide, or sodium dioxophosphate borate, or one or more of these. The adhesive material includes one or more of the following: polyvinylidene fluoride, styrene-butadiene rubber, sodium carboxymethyl cellulose, polyacrylic acid, polyamide, polyvinyl alcohol, polyethyleneimine, polyacrylonitrile, polyimide, or polyacrylate.

8. The preparation method according to claim 1, characterized in that, In step S5, the pressure of the pressurization process is 0-200 MPa; The temperature of the heat treatment is 25℃~200℃.

9. A solid-liquid hybrid battery prepared by the preparation method according to any one of claims 1-8, characterized in that, The solid-liquid hybrid battery includes: a lithium-ion solid-liquid hybrid battery or a sodium-ion solid-liquid hybrid battery.

10. An application of the solid-liquid hybrid battery according to claim 9, characterized in that, The solid-liquid hybrid battery is applied to one or more of the following: electric vehicles, hybrid electric vehicles, electric bicycles, energy storage power stations, portable electronic devices, mobile power supplies, drones, power tools, wearable devices, medical electronic devices, aerospace vehicles, marine propulsion systems, or grid frequency regulation energy storage systems.

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