A transfer method of a solid electrolyte membrane, an electrode provided with a solid electrolyte membrane on a surface, and a solid-state battery

Abstract

This invention belongs to the field of lithium-ion secondary battery technology, specifically relating to a method for transferring a solid electrolyte membrane, an electrode with a solid electrolyte membrane on its surface, and a solid-state battery. This invention obtains an adhesive with both moderate adhesion and high elasticity by compounding polyisobutylene with a styrene-ethylene-butene-styrene block copolymer (SEBS). This adhesive utilizes the synergistic effect of polyisobutylene providing interfacial adhesion and SEBS providing stress buffering, achieving temperature-sensitive transfer control with low-temperature pickup and high-temperature release within a specific temperature range. By adjusting the ratio of polyisobutylene to SEBS, a rigid-tough layer formulation for the positive electrode and a flexible layer formulation for the negative electrode are obtained, further constructing a bilayer solid electrolyte membrane. This invention achieves high-fidelity transfer of the solid electrolyte membrane to the electrode, significantly reducing interfacial defects and short-circuit risks, improving the cycle stability and thermal safety of the battery, and is suitable for the large-scale manufacturing of high-energy-density all-solid-state batteries.

Description

Technical Field

[0001] This invention belongs to the field of lithium-ion secondary battery technology, specifically relating to a solid electrolyte membrane transfer method, an electrode with a solid electrolyte membrane on its surface, and a solid battery. Background Technology

[0002] With the rapid development of new energy vehicles, energy storage systems, and consumer electronics, the market demand for high-energy-density and high-safety rechargeable batteries is becoming increasingly urgent. All-solid-state batteries, due to their use of non-flammable solid electrolytes, fundamentally solve the safety hazards of traditional liquid lithium batteries, such as leakage and fire. They are also compatible with high-capacity positive and negative electrode materials, and are considered a key technology for achieving energy densities above 400Wh / kg. In the fabrication process of all-solid-state batteries, the precise integration of thin-film solid electrolytes is a crucial step in achieving optimal battery performance.

[0003] Currently, the main methods for forming solid electrolyte films include cold pressing, hot pressing, coating, vapor deposition, and 3D printing. Each method has its own characteristics. For example, cold pressing and hot pressing can obtain relatively dense electrolyte layers, but the equipment cost is high and they can easily damage the electrodes; coating is a simple process, but it is difficult to precisely control the thickness and uniformity; vapor deposition and 3D printing can achieve patterned integration, but their production efficiency is low and the cost is high, making it difficult to meet the needs of large-scale production. In recent years, transfer printing has received widespread attention as a continuous, low-temperature, and patternable manufacturing method. This method can ensure the quality of the electrolyte film while avoiding damage to the electrodes caused by high-temperature processes, and it has good application prospects.

[0004] However, existing transfer technologies still suffer from a series of insurmountable core defects. Traditional adhesives such as polydimethylsiloxane, polyimide adhesives, acrylic pressure-sensitive adhesives, styrene-butadiene rubber, and hydrogenated nitrile rubber have insufficient interfacial bonding with sulfide, oxide, and halide solid electrolytes and are prone to side reactions, leading to localized peeling, voids, or microcracks during the transfer process, resulting in low transfer success rates and high interfacial defect density. Furthermore, the adhesion of these adhesives is difficult to precisely control; either excessive adhesion prevents the electrolyte layer from being efficiently loaded onto the electrode, or insufficient adhesion leads to pickup failure, making it difficult to achieve a balance between pickup and release. Solid electrolyte materials are inherently brittle and easily crack or break during peeling or transfer, affecting battery reliability. In addition, some organic adhesives have solvent residue issues, hindering interfacial ion conduction, and their poor temperature sensitivity makes them prone to softening or decomposition at high temperatures, limiting the subsequent encapsulation process window. These combined problems lead to increased battery short-circuit rates, increased risk of thermal runaway, and deterioration in cycle performance, severely hindering the industrialization of all-solid-state batteries.

[0005] Therefore, there is an urgent need to develop a novel transfer adhesive system that combines moderate adhesion, good elasticity, chemical inertness, and low residue properties to achieve high-quality, repeatable solid electrolyte transfer, thereby providing technical support for the large-scale manufacturing of high-energy-density all-solid-state batteries. Summary of the Invention

[0006] To address the shortcomings of existing technologies, this invention proposes a method for transferring solid electrolyte membranes, an electrode with a solid electrolyte membrane on its surface, and a solid-state battery. This invention utilizes a specific ratio and molecular weight control of polyisobutylene and styrene-ethylene-butene-styrene block copolymer (SEBS block copolymer) to achieve suitable adhesive properties and elasticity in the adhesive, thus providing an innovative solution for achieving high-quality transfer of solid electrolyte membranes.

[0007] The first objective of this invention is achieved through the following technical solution:

[0008] A method for transferring a solid electrolyte membrane includes the following steps:

[0009] A) Provide a component to be transferred, the component to be transferred including a carrier and a solid electrolyte membrane formed on the surface of the carrier; stack the component to be transferred with an electrode, with the solid electrolyte membrane facing the surface of the electrode, and apply pressure at 40-100°C to make the solid electrolyte membrane adhere to the surface of the electrode;

[0010] B) Peel off the carrier to transfer the solid electrolyte membrane from the carrier to the electrode surface, thereby obtaining an electrode with a solid electrolyte membrane on its surface;

[0011] The method for preparing the component to be transferred includes the following steps:

[0012] a) A slurry is prepared by mixing a composite adhesive, a solid electrolyte, and a solvent, wherein the raw materials of the composite adhesive include polyisobutylene (PIB) and styrene-ethylene-butene-styrene block copolymer (SEBS block copolymer), wherein the content of polyisobutylene is 30-60 wt%, the content of SEBS block copolymer is 20-60 wt%, and the viscosity-average molecular weight of polyisobutylene is 200,000-4,000,000 Da.

[0013] b) The slurry is coated onto a carrier and dried to obtain the component to be transferred.

[0014] Preferably, in step A), the carrier is selected from one or more of PET film, PI film, aluminum foil, copper foil, composite foil, glass, stainless steel, and PTFE board.

[0015] More preferably, the carrier is a PET film, PI film, aluminum foil, copper foil, or composite foil.

[0016] Preferably, in step A), pressure is applied by one or more of the following methods: flat plate pressing, roller pressing, or isostatic pressing.

[0017] Preferably, in step A), the temperature when applying pressure is 60-80°C.

[0018] Preferably, in step A), the pressure conditions are: pressure 0.5-100 MPa, pressure holding time 1-30 min.

[0019] Preferably, step B) is followed by an annealing process; the annealing process is carried out in an inert atmosphere, the annealing temperature is 20-95℃, and the annealing time is 10-120min.

[0020] Preferably, the solid electrolyte is selected from one or more of sulfide electrolytes, oxide electrolytes, and halide electrolytes.

[0021] More preferably, the sulfide electrolyte is selected from one or more of LPS, LPSCl, LGPS, LSPS, and LPSI.

[0022] More preferably, the oxide electrolyte is selected from one or more of LLZO, LATP, and LLTO.

[0023] More preferably, the halide electrolyte is selected from one or more of LIC, LZC, LZOC, LAOC, LZAOC, LNOC, LTOC, and bromine- or iodine-containing halide electrolytes.

[0024] Preferably, the electrode is a positive electrode.

[0025] More preferably, the active material of the positive electrode is selected from one or more of lithium nickel cobalt manganese oxide, lithium nickel cobalt aluminum oxide, lithium-rich manganese-based positive electrode materials, and high-nickel oxide positive electrode materials.

[0026] Preferably, the electrode is a negative electrode.

[0027] More preferably, the active material of the negative electrode is selected from one or more of graphite, silicon carbide, silicon oxide, nano-silicon, micron-silicon, lithium metal, or lithium-silicon alloy.

[0028] Preferably, the raw materials of the composite adhesive are also selected from one or more of tackifying resins, plasticizers, and antioxidants.

[0029] More preferably, the tackifying resin accounts for 5-15 wt% of the total mass of the composite adhesive.

[0030] More preferably, the plasticizer accounts for 0-10 wt% of the total mass of the composite adhesive.

[0031] More preferably, the antioxidant accounts for 0.1-1 wt% of the total mass of the composite adhesive.

[0032] More preferably, the tackifying resin is selected from one or more of C5 petroleum resin, C9 petroleum resin, and rosin ester.

[0033] More preferably, the plasticizer is selected from one or more of liquid paraffin, dioctyl phthalate (DOP), and vegetable oil derivatives.

[0034] More preferably, the antioxidant is selected from one or more of hindered phenolic antioxidants and phosphite antioxidants.

[0035] Preferably, the preparation method of the composite adhesive includes the following steps: mixing polyisobutylene, SEBS block copolymer, tackifying resin, plasticizer, and antioxidant, heating to melt, keeping at the temperature for 1-3 h, adding to a twin-screw extruder, co-extruding at 155-165℃ and 350-550 rpm, granulating, and obtaining the composite adhesive.

[0036] More preferably, the mixing heating temperature is 110-150℃.

[0037] Preferably, the styrene content in the SEBS block copolymer is 15-40 wt%.

[0038] More preferably, the SEBS block copolymer has a linear structure, a star structure, or a combination thereof.

[0039] Preferably, the solvent is a low-polarity solvent, a non-polar solvent, or a mixture thereof.

[0040] More preferably, the solvent is selected from one or more of toluene, p-xylene, cyclohexane, and isobutyl isobutyrate.

[0041] Preferably, the solid content of the slurry is 1-20%.

[0042] More preferably, the solid content of the slurry is 3-10%.

[0043] More preferably, the solid content of the slurry is 5%.

[0044] Preferably, in step b), the slurry is applied to the carrier by scraping, screen printing or spraying.

[0045] Preferably, in step b), the slurry is further subjected to pressing after drying.

[0046] More preferably, the pressing process is carried out at a temperature of 60-100℃, a pressure of 50-150 MPa, and a time of 1-10 min.

[0047] Preferably, in step b), the drying temperature is 60-150℃.

[0048] More preferably, the thickness of the solid electrolyte membrane is 10-200 μm.

[0049] More preferably, the thickness of the solid electrolyte membrane is 20-100 μm.

[0050] Preferably, when the electrode is a positive electrode, the mass ratio of polyisobutylene to SEBS block copolymer in the composite adhesive of the solid electrolyte membrane to be transferred is 60:30 to 30:60.

[0051] More preferably, when the electrode is a positive electrode, the mass ratio of polyisobutylene to SEBS block copolymer in the composite adhesive of the solid electrolyte membrane to be transferred is 60:30 to 50:40.

[0052] Preferably, when the electrode is a negative electrode, the mass ratio of polyisobutylene to SEBS block copolymer in the composite adhesive of the solid electrolyte membrane to be transferred is 60:30 to 30:60.

[0053] More preferably, when the electrode is a negative electrode, the mass ratio of polyisobutylene to SEBS block copolymer in the composite adhesive of the solid electrolyte membrane to be transferred is 40:50 to 30:60.

[0054] Preferably, the method is applicable to transferring the solid electrolyte membrane only to the positive electrode surface, transferring the solid electrolyte membrane only to the negative electrode surface, or transferring the solid electrolyte membrane to both the positive and negative electrode surfaces respectively.

[0055] Further preferably, when the solid electrolyte membrane is transferred to the positive electrode surface and the negative electrode surface respectively, the solid electrolyte membrane on the positive electrode side and the solid electrolyte membrane on the negative electrode side adopt a composite adhesive system with different mass ratios of polyisobutylene and SEBS block copolymer, so as to meet the rigid support requirements of the positive electrode side and the buffering requirements of the negative electrode side respectively.

[0056] Preferably, the peel strength between the solid electrolyte membrane and the carrier is 0.1-1.0 N / cm.

[0057] Preferably, the peel strength between the solid electrolyte membrane and the electrode is 2.0-6.0 N / cm.

[0058] This solution employs a composite adhesive system based on the synergistic effect of polyisobutylene and SEBS block copolymer. A solid electrolyte membrane to be transferred is first formed on a carrier, and then directionally transferred to the electrode surface under controlled temperature, pressure, and time conditions, achieving low-temperature, low-pressure, and high-fidelity transfer of the solid electrolyte membrane. Polyisobutylene provides low surface energy, good chemical stability, and controllable adhesion, enabling the adhesive to provide a continuous bonding network during the electrolyte membrane formation stage and moderate interfacial forces during the transfer stage. SEBS block copolymer provides elastic modulus, tear resistance, and stress buffering capacity, making the brittle solid electrolyte less prone to through-cracks and large-area damage during peeling, bonding, and transfer. The combination of these two components forms a temperature-dependent viscoelastic system, ensuring stable pickup of the electrolyte membrane at lower temperatures, and enabling release from the carrier to the electrode through interfacial adhesion and modulus changes near 20-80℃, especially 40-100℃, thus forming a dynamic transfer mechanism with strong pickup, locking, and release capabilities. For the positive electrode side, a higher proportion of polyisobutylene and a relatively lower proportion of SEBS block copolymers are beneficial for balancing higher ion conductivity and higher support strength, to meet the interfacial pressure requirements of high-nickel and lithium-rich manganese-based positive electrodes. For the negative electrode side, a higher proportion of SEBS block copolymers is beneficial for providing a more flexible elastomer structure to buffer the volume changes and local stress concentrations of silicon-based and lithium metal negative electrodes during cycling. Optional annealing further improves interfacial contact after transfer without damaging the electrode structure.

[0059] The second objective of this invention is achieved through the following technical solution:

[0060] An electrode with a solid electrolyte membrane on its surface is prepared by the above-mentioned solid electrolyte membrane transfer method.

[0061] Preferably, the electrode with a solid electrolyte membrane on its surface is a positive electrode with a solid electrolyte membrane on its surface and / or a negative electrode with a solid electrolyte membrane on its surface.

[0062] More preferably, in the positive electrode with a solid electrolyte membrane on its surface, the solid electrolyte membrane is a composite adhesive system with a mass ratio of polyisobutylene to SEBS block copolymer of 60:30 to 30:60.

[0063] More preferably, in the positive electrode with a solid electrolyte membrane on its surface, the solid electrolyte membrane is a composite adhesive system with a mass ratio of polyisobutylene to SEBS block copolymer of 60:30 to 50:40.

[0064] More preferably, in the negative electrode with a solid electrolyte membrane on its surface, the solid electrolyte membrane is a composite adhesive system with a mass ratio of polyisobutylene to SEBS block copolymer of 60:30 to 30:60.

[0065] More preferably, in the negative electrode with a solid electrolyte membrane on its surface, the solid electrolyte membrane is a composite adhesive system with a mass ratio of polyisobutylene to SEBS block copolymer of 40:50 to 30:60.

[0066] Preferably, the solid electrolyte membrane on the electrode surface is a complete and continuous membrane layer, and forms at least a partial conformal contact with the electrode surface.

[0067] Preferably, the electrodes with a solid electrolyte membrane on their surface are suitable for roll-to-roll continuous manufacturing processes, mold battery assembly processes, and pouch battery assembly processes.

[0068] The third objective of this invention is achieved through the following technical solution:

[0069] A solid-state battery comprising a positive electrode and a negative electrode.

[0070] The positive electrode is an electrode on which a solid electrolyte membrane is provided on the surface;

[0071] And / or, the negative electrode is an electrode on the surface of which a solid electrolyte membrane is provided;

[0072] When either the positive electrode or the negative electrode is an electrode with a solid electrolyte membrane on its surface, the solid electrolyte membrane is located between the positive electrode and the negative electrode;

[0073] When both the positive electrode and the negative electrode are electrodes with a solid electrolyte membrane on their surface, the solid electrolyte membranes on their surfaces are arranged opposite each other and at least partially in contact, and the solid electrolyte membrane on the positive electrode side and the solid electrolyte membrane on the negative electrode side constitute a double-layer solid electrolyte structure.

[0074] More preferably, the solid-state battery is assembled by stacking and pressing.

[0075] More preferably, the solid-state battery achieves dense interfacial contact between the positive electrode, negative electrode, and solid electrolyte membrane during the assembly process using isostatic pressing or other pressing methods.

[0076] More preferably, the pressure applied during the assembly of the solid-state battery is 0.5-50 MPa.

[0077] Preferably, in the solid electrolyte membrane on the positive electrode side, the mass ratio of polyisobutylene to SEBS block copolymer in the composite adhesive is 60:30 to 30:60.

[0078] More preferably, in the solid electrolyte membrane on the positive electrode side, the mass ratio of polyisobutylene to SEBS block copolymer in the composite adhesive is 60:30 to 50:40.

[0079] Preferably, in the solid electrolyte membrane on the negative electrode side, the mass ratio of polyisobutylene to SEBS block copolymer in the composite adhesive is 60:30 to 30:60.

[0080] More preferably, in the solid electrolyte membrane on the negative electrode side, the mass ratio of polyisobutylene to SEBS block copolymer in the composite adhesive is 40:50 to 30:60.

[0081] Preferably, the cathode in the solid-state battery is one or more of lithium nickel cobalt manganese oxide, lithium nickel cobalt aluminum oxide, lithium-rich manganese-based cathode material, or high-nickel oxide cathode material.

[0082] Preferably, the negative electrode in the solid-state battery is one or more of graphite, silicon-carbon, silicon-oxygen, nano-silicon, micron-silicon, lithium metal, lithium-silicon alloy, or a negative electrode-free system.

[0083] Preferably, the solid electrolyte membrane in the solid-state battery is selected from one or more of sulfides, oxides, and halides.

[0084] Preferably, the present invention can be used in a negative electrode-free system.

[0085] This scheme utilizes electrodes with solid electrolyte membranes on their surfaces to construct solid-state batteries. Specifically, when solid electrolyte membranes are placed on both the positive and negative electrodes and are positioned opposite each other and at least partially in contact during assembly, a bilayer solid electrolyte structure can be formed. This bilayer structure is not a simple superposition, but rather an intermediate interface layer with multiple toughening and stress management functions, constructed collaboratively by a relatively rigid electrolyte membrane on the positive electrode side and a relatively flexible electrolyte membrane on the negative electrode side. The positive electrode side membrane emphasizes support and ion conduction continuity to withstand the expansion pressure of positive electrode active materials such as high-nickel positive electrodes; the negative electrode side membrane emphasizes flexibility and buffering to accommodate volume changes in silicon-based negative electrodes, lithium metal negative electrodes, etc., during deposition, stripping, and cycling. With the bilayer membranes positioned opposite each other and in contact, during crack initiation and propagation, mechanisms such as crack deflection, soft-layer bridging, and interface energy dissipation can prevent cracks from directly penetrating the entire electrolyte layer. Compared to a single-layer homogeneous brittle membrane, this is more beneficial for maintaining isolation functions, reducing short-circuit risk, and improving cycle stability. Meanwhile, since both membranes are constructed based on the PIB-SEBS block copolymer system, they have better interfacial compatibility and can reduce interfacial impedance and side reactions caused by different adhesive types.

[0086] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0087] 1. This invention solves the contradiction between pick-up and release that is difficult to achieve in traditional single-component adhesives by combining polyisobutylene with SEBS block copolymer. Polyisobutylene provides moderate interfacial adhesion and chemical inertness, while SEBS block copolymer provides high elastic modulus and tear resistance. The combination of the two enables the adhesive to have sufficient cohesive strength during pick-up and smooth release during transfer.

[0088] 2. This invention achieves directional design of the mechanical properties of solid electrolyte membranes by controlling the mass ratio of polyisobutylene to SEBS block copolymer. The positive electrode side uses a formulation with a lower SEBS block copolymer content, resulting in a higher membrane modulus capable of withstanding the volume expansion pressure of the positive electrode material; the negative electrode side uses a formulation with a higher SEBS block copolymer content, resulting in excellent membrane elasticity, capable of buffering the large volume changes of the silicon-based negative electrode and suppressing lithium dendrite penetration.

[0089] 3. This invention utilizes the temperature-sensitive viscoelasticity of the composite adhesive to establish a transfer process of low-temperature pickup and high-temperature release. At room temperature, the adhesive maintains sufficient modulus to stably pick up the electrolyte membrane. Upon heating, the adhesive modulus decreases and the adhesion force reduces, promoting the release of the electrolyte membrane to the electrode surface, thus achieving stepwise control of pickup and release.

[0090] 4. This invention uses the same material system to prepare solid electrolyte membranes on the positive and negative electrode sides separately, and then presses them together to form an integrated interface. The two membranes are based on the same polymer matrix, exhibiting excellent interfacial compatibility, avoiding interfacial impedance and side reactions caused by different material systems, and improving the interfacial reliability of the battery during cycling.

[0091] 5. Through the synergistic effect of the above-mentioned material design and process innovation, the present invention enables solid-state batteries to operate stably under lower pressure, achieving excellent rate performance and cycle life, while significantly improving battery safety. Attached Figure Description

[0092] Figure 1 Temperature-adhesion curves of LPSCl electrolyte membranes prepared in Examples 1-4 and Comparative Examples 1-4;

[0093] Figure 2 Temperature-adhesion curves of LPSCl electrolyte membranes prepared in Examples 1, 5-8 and Comparative Examples 17-18;

[0094] Figure 3 Temperature-adhesion curves of LPSCl electrolyte membranes prepared in Examples 9-12 and Comparative Examples 5-8;

[0095] Figure 4 CV curves of the mold batteries prepared in Examples 10 and 18;

[0096] Figure 5 The constant current charge-discharge curve of the mold battery prepared in Example 18; Detailed Implementation

[0097] The following will provide a clear and complete description of the concept, specific structure, and technical effects of the present invention in conjunction with the embodiments and accompanying drawings, so as to fully understand the purpose, solution, and effects of the present invention. It should be noted that, unless otherwise specified, the embodiments and features described in the embodiments of the present invention can be combined with each other.

[0098] The materials used in the embodiments and comparative examples of this invention are described below:

[0099] Polyisobutylene: viscosity-average molecular weight 200,000, 1,000,000, 2,000,000, 3,000,000, 4,000,000.

[0100] SEBS block copolymer: Model YH-503, styrene content 30%-40%.

[0101] Tackifying resin: C5 petroleum resin.

[0102] Plasticizer: DOP, purchased from Merck.

[0103] Antioxidant: Irganox 1010, purchased from Merck.

[0104] Solid electrolytes: LPSCl (Li6PS5Cl), purchased from Shanghai Yili; LTOC (LiTaOCl4), purchased from GRINM; LPSI (Li7P2S8I), purchased from Shanghai Yili; LLZO (Li7La3Zr2O) 12 Purchased from BTR.

[0105] Cathode material: NCM9 series, purchased from Libao / Dangsheng.

[0106] Anode materials: Nano-silicon, particle size 30nm, specific capacity 3500 mAh / g, purchased from BTR; SiC, specific capacity 2200mAh / g, purchased from BTR.

[0107] Testing and definition of key parameters:

[0108] Transfer success rate: The percentage of successful transfers out of the total number of attempts during the process of transferring a solid electrolyte membrane prepared on a temporary carrier intact, undamaged, and with good interfacial contact with the target electrode onto the electrode.

[0109] Interface defect density: The number of interface defects that can be observed per square centimeter on the electrolyte surface after the electrolyte membrane is transferred to the positive and negative electrodes. Defects include pinholes, cracks, and areas of uneven thickness.

[0110] Electrolyte membrane breakage rate: The percentage of electrolyte membrane area with macroscopically damaged sections visible to the naked eye or detectable by testing instruments during the entire battery manufacturing process, including preparation, transfer, cutting, stacking, and packaging. The broken area is statistically analyzed for electrolyte membranes with dimensions of 10cm × 6cm × 0.100mm.

[0111] Density test: The ratio of the apparent density to the theoretical density of the solid electrolyte was tested using the immersion method. In a -60℃ dew point room, the mass m1 of the solid electrolyte sheet was weighed and suspended in anhydrous silicone oil solvent; the test mass was m0. Based on the silicone oil density ρ1, the density was calculated as m1 / ((m1-m0) / ρ1) / ρ0, where ρ0 is the theoretical density of the solid electrolyte.

[0112] Electrolyte membrane lithium-ion conductivity test: In a glove box, using a PPEK mold, the solid electrolyte membrane was held under a pressure of 500MPa for 10 minutes, and the AC impedance was tested at 25℃, with a frequency range of 1MHz-0.1Hz and a voltage amplitude of 10mV.

[0113] Limiting current density test: Assemble a Li / electrolyte / Li symmetric battery, sandwich the electrolyte sheet between two lithium metal foils, apply a pressure of 370 MPa and then release it to 5 MPa, gradually increase the current density at constant 1-hour intervals, perform constant current charge-discharge cycles at each current density until the voltage drops to zero, and record the current density when a short circuit occurs.

[0114] Adhesion test: Under an inert atmosphere with water and oxygen content both below 0.01 ppm, the interfacial adhesion between the sulfide composite electrolyte membrane and the electrode was tested using the 180° peel method. The electrolyte membrane and electrode were hot-pressed together at 0-150℃ and 8 MPa for 2 min to form a composite sample. A universal testing machine was used to perform a 180° peel test at a speed of 50 mm / min. The average force in the stable region of the force-displacement curve was taken as the peel strength, in N / 20 mm. Each test was performed three times, and the average value was taken.

[0115] Solid-state battery cycle testing: Constant current charge-discharge test was conducted at 25℃, with a voltage range of 2.5V-4.25V and a constant voltage charging cutoff current of 0.05C. First, rate charge-discharge tests were performed at rates of 0.1C, 0.33C, 0.5C, 1.0C, and 2.0C, followed by a long-cycle test at 0.5C.

[0116] The present invention will be further illustrated by specific embodiments below, but the scope of protection of the present invention is not limited thereto.

[0117] The composite adhesives for solid electrolyte transfer printing described in this invention and comparative examples are prepared via a melt blending extrusion process. Specifically, polyisobutylene, SEBS block copolymer, tackifying resin, plasticizer, and antioxidant are mixed according to the proportions in Table 1 or Table 2, heated to 120°C for melting, held at that temperature for 2 hours, and then fed into a twin-screw extruder. The mixture is then blended and extruded at 155-165°C and 350-550 rpm, and granulated to obtain composite adhesive powder. The obtained composite adhesive powder is dissolved in a solvent and stirred thoroughly at 60°C to prepare a 5% solid content adhesive solution. The solvent is toluene, p-xylene, cyclohexane, or isobutyl isobutyrate. The obtained adhesive solution is mixed with a solid electrolyte and a solvent to prepare a slurry. After the slurry is prepared, it is coated onto the surface of a carrier. The carrier is a PET film, Al foil, Cu foil, or PI film. After coating, the solvent is removed by vacuum drying at 80°C for 6 hours to obtain a solid electrolyte membrane. The obtained solid electrolyte membrane is pressed at 80℃ and 100MPa for 3 minutes to form a dense electrolyte layer. The pressed solid electrolyte membrane is then bonded to the electrode and held at 40-100℃ and 1-100MPa for 2-30 minutes to transfer the electrolyte membrane to the electrode surface. The bonding method can be flat pressing, roll pressing, or isostatic pressing. Subsequently, the carrier is slowly peeled off to obtain a composite electrode with the solid electrolyte membrane transferred onto it. The positive electrode, solid electrolyte membrane, and negative electrode are stacked sequentially using a lamination method and pressed under isostatic pressure to obtain a solid-state battery. The battery assembly pressure is 1-4 tons, and the pressure is held for 5 minutes.

[0118] The variation parameters of each embodiment and comparative example are detailed in Tables 1 and 2.

[0119] Table 1 Preparation parameters of the examples

[0120]

[0121] Table 2 Preparation parameters of the comparative examples

[0122]

[0123] Example 1

[0124] The solid-state battery preparation method of Example 1 includes the following steps:

[0125] (1) Polyisobutylene (viscosity-average molecular weight 200,000), SEBS block copolymer, C5 tackifying resin, DOP and Irganox 1010 were mixed in a mass ratio of 60:30:8:2:0.5, heated to 120°C to melt and held at that temperature for 2 hours. Then, the mixture was fed into a twin-screw extruder and co-extruded and granulated at 160°C and 400 rpm to obtain the composite adhesive powder of Example 1. The obtained composite adhesive powder was dissolved in toluene and stirred thoroughly at 60°C to obtain an adhesive solution with a solid content of 5%.

[0126] (2) The LPSCl electrolyte and the adhesive solution obtained in step (1) are mixed at a mass ratio of 95:5, and toluene is added to adjust the solid content of the slurry. After stirring evenly, the mixture is coated on the surface of a PET film, vacuum dried at 80°C for 6 hours, and then pressed at 80°C and 100MPa for 3 minutes to obtain the solid electrolyte membrane of Example 1 with a thickness of 100μm.

[0127] (3) Align the solid electrolyte membrane obtained in step (2) with the NCM9 system positive electrode, and use a flat plate bonding method to hold the pressure at 60°C and 20MPa for 5 minutes to transfer the solid electrolyte membrane to the surface of the positive electrode. Then slowly peel off the PET film to obtain a composite positive electrode with the solid electrolyte membrane transferred.

[0128] (4) The composite positive electrode obtained in step (3) is stacked with the LiIn alloy negative electrode so that the solid electrolyte film on the surface of the composite positive electrode comes into contact with the LiIn alloy negative electrode. The battery is assembled under an assembly pressure of 1t to obtain the solid battery of Example 1.

[0129] Example 2

[0130] The solid-state battery in Example 2 differs from that in Example 1 in that the adhesive formulation in step (1) is different; the other steps are the same as in Example 1.

[0131] (1) Polyisobutylene (viscosity average molecular weight 200,000), SEBS block copolymer, C5 tackifying resin, DOP, and Irganox 1010 were mixed in a mass ratio of 50:40:8:2:0.5 and the adhesive solution was prepared according to the method of step (1) in Example 1.

[0132] (2-4) Following the steps (2-4) of Example 1, the solid-state battery of Example 2 is obtained.

[0133] Example 3

[0134] The solid-state battery in Example 3 differs from that in Example 1 in that the adhesive formulation in step (1) is different; the other steps are the same as in Example 1.

[0135] (1) Polyisobutylene (viscosity average molecular weight 200,000), SEBS block copolymer, C5 tackifying resin, DOP, and Irganox 1010 were mixed in a mass ratio of 40:50:8:2:0.5 and the adhesive solution was prepared according to the method of step (1) in Example 1.

[0136] (2-4) Following the steps (2-4) of Example 1, the solid-state battery of Example 3 is obtained.

[0137] Example 4

[0138] The solid-state battery in Example 4 differs from that in Example 1 in that the adhesive formulation in step (1) is different; the other steps are the same as in Example 1.

[0139] (1) Polyisobutylene (viscosity average molecular weight 200,000), SEBS block copolymer, C5 tackifying resin, DOP, and Irganox 1010 were mixed in a mass ratio of 30:60:8:2:0.5 and the adhesive solution was prepared according to the method of step (1) in Example 1.

[0140] (2-4) Following the steps (2-4) of Example 1, the solid-state battery of Example 4 is obtained.

[0141] Example 5

[0142] The solid-state battery in Example 5 differs from that in Example 1 in that the molecular weight of the polyisobutylene is different in step (1), while the other steps are the same as in Example 1:

[0143] (1) Polyisobutylene (viscosity average molecular weight 1 million), SEBS block copolymer, C5 tackifying resin, DOP, and Irganox 1010 were mixed in a mass ratio of 60:30:8:2:0.5 and the adhesive solution was prepared according to the method of step (1) in Example 1.

[0144] (2-4) Following the steps (2-4) of Example 1, the solid-state battery of Example 5 is obtained.

[0145] Example 6

[0146] The solid-state battery in Example 6 differs from that in Example 1 in that the molecular weight of the polyisobutylene is different in step (1), while the other steps are the same as in Example 1:

[0147] (1) Polyisobutylene (viscosity average molecular weight 2 million), SEBS block copolymer, C5 tackifying resin, DOP, and Irganox 1010 were mixed in a mass ratio of 60:30:8:2:0.5 and the adhesive solution was prepared according to the method of step (1) in Example 1.

[0148] (2-4) Following the steps (2-4) of Example 1, the solid-state battery of Example 6 is obtained.

[0149] Example 7

[0150] The solid-state battery in Example 7 differs from that in Example 1 in that the molecular weight of the polyisobutylene is different in step (1), while the other steps are the same as in Example 1:

[0151] (1) Polyisobutylene (viscosity average molecular weight 3 million), SEBS block copolymer, C5 tackifying resin, DOP, and Irganox 1010 were mixed in a mass ratio of 60:30:8:2:0.5 and the adhesive solution was prepared according to the method of step (1) in Example 1.

[0152] (2-4) Following the steps (2-4) of Example 1, the solid-state battery of Example 7 is obtained.

[0153] Example 8

[0154] The solid-state battery in Example 8 differs from that in Example 1 in that the molecular weight of the polyisobutylene is different in step (1), while the other steps are the same as in Example 1:

[0155] (1) Polyisobutylene (viscosity average molecular weight 4 million), SEBS block copolymer, C5 tackifying resin, DOP, and Irganox 1010 were mixed in a mass ratio of 60:30:8:2:0.5 and the adhesive solution was prepared according to the method of step (1) in Example 1.

[0156] (2-4) Following the steps (2-4) of Example 1, the solid-state battery of Example 8 is obtained.

[0157] Example 9

[0158] The solid-state battery preparation method of Example 9 includes the following steps:

[0159] (1) Polyisobutylene (viscosity-average molecular weight 2 million), SEBS block copolymer, C5 tackifying resin, DOP, and Irganox 1010 were mixed in a mass ratio of 60:30:8:2:0.5, heated to 120°C to melt, kept at that temperature for 2 hours, and then fed into a twin-screw extruder. The mixture was co-extruded at 160°C and 500 rpm, and granulated to obtain the composite adhesive powder of Example 9. The obtained composite adhesive powder was dissolved in isobutyl isobutyrate and stirred thoroughly at 60°C to prepare a 5% solid content adhesive solution.

[0160] (2) The LPSCl electrolyte and the adhesive solution obtained in step (1) are mixed at a mass ratio of 95:5. Isobutyl isobutyrate is added to adjust the solid content of the slurry. After stirring evenly, the mixture is coated onto a PET film and dried under vacuum at 80°C for 6 hours. Then, it is pressed at 80°C and 100MPa for 3 minutes to obtain the solid electrolyte membrane of Example 9 with a thickness of 100μm.

[0161] (3) Align the solid electrolyte membrane obtained in step (2) with the nano-silicon anode, use a flat plate bonding method, heat to 60°C, pressurize 30MPa and hold for 5 minutes to transfer the electrolyte membrane to the surface of the anode, slowly peel off the PET film to obtain a composite anode with the solid electrolyte membrane transferred.

[0162] (4) Stack the NCM9 positive electrode and the composite negative electrode obtained in step (3) so that the NCM9 positive electrode and the solid electrolyte membrane on the surface of the composite negative electrode come into contact. The battery is assembled under an assembly pressure of 4t to obtain the solid battery of Example 9.

[0163] Example 10

[0164] The solid-state battery of Example 10 differs from that of Example 9 in that the adhesive formulation in step (1) is different; the other steps are the same as those of Example 9.

[0165] (1) Polyisobutylene (viscosity average molecular weight 2 million), SEBS block copolymer, C5 tackifying resin, DOP, and Irganox 1010 were mixed in a mass ratio of 50:40:8:2:0.5 and the adhesive solution was prepared according to the method of step (1) in Example 9.

[0166] (2-4) Following the steps (2-4) of Example 9, the solid-state battery of Example 10 is obtained.

[0167] Example 11

[0168] The solid-state battery in Example 11 differs from that in Example 9 in that the adhesive formulation in step (1) is different; the other steps are the same as in Example 9.

[0169] (1) Polyisobutylene (viscosity average molecular weight 2 million), SEBS block copolymer, C5 tackifying resin, DOP, and Irganox 1010 were mixed in a mass ratio of 40:50:8:2:0.5 and the adhesive solution was prepared according to the method of step (1) in Example 9.

[0170] (2-4) Following step (2-4) of Example 9, the solid-state battery of Example 11 is obtained.

[0171] Example 12

[0172] The solid-state battery of Example 12 differs from that of Example 9 in that the adhesive formulation in step (1) is different; the other steps are the same as those of Example 9.

[0173] (1) Polyisobutylene (viscosity average molecular weight 2 million), SEBS block copolymer, C5 tackifying resin, DOP, and Irganox 1010 were mixed in a mass ratio of 30:60:8:2:0.5 and the adhesive solution was prepared according to the method of step (1) in Example 9.

[0174] (2-4) Following the steps (2-4) of Example 9, the solid-state battery of Example 12 was obtained.

[0175] Example 13

[0176] The solid-state battery in Example 13 differs from that in Example 12 in that the transfer temperature in step (3) is different; the other steps are the same as in Example 12.

[0177] (1-2) Proceed according to step (1-2) of Example 12.

[0178] (3) Align the solid electrolyte membrane obtained in step (2) of Example 12 with the nano-silicon anode, use a flat plate bonding method, heat to 40°C, pressurize 20MPa and hold for 5 minutes to transfer the electrolyte membrane to the surface of the anode, slowly peel off the PET film to obtain a composite anode with the solid electrolyte membrane transferred.

[0179] (4) Following step (4) of Example 12, the solid-state battery of Example 13 is obtained.

[0180] Example 14

[0181] The solid-state battery in Example 14 differs from that in Example 12 in that the transfer temperature in step (3) is different; the other steps are the same as in Example 12.

[0182] (1-2) Proceed according to step (1-2) of Example 12.

[0183] (3) Align the solid electrolyte membrane obtained in step (2) of Example 12 with the nano-silicon anode, use a flat plate bonding method, heat to 80°C, pressurize 20MPa and hold for 5 minutes to transfer the electrolyte membrane to the surface of the anode, slowly peel off the PET film to obtain a composite anode with the solid electrolyte membrane transferred.

[0184] (4) Following step (4) of Example 12, the solid-state battery of Example 14 is obtained.

[0185] Example 15

[0186] The solid-state battery in Example 15 differs from that in Example 12 in that the transfer temperature is different in step (3), while the other steps are the same as in Example 12:

[0187] (1-2) Proceed according to step (1-2) of Example 12.

[0188] (3) Align the solid electrolyte membrane obtained in step (2) of Example 12 with the nano-silicon anode, use a flat plate bonding method, heat to 100°C, pressurize 20MPa and hold for 5 minutes to transfer the electrolyte membrane to the surface of the anode, slowly peel off the PET film to obtain a composite anode with the solid electrolyte membrane transferred.

[0189] (4) Following step (4) of Example 12, the solid-state battery of Example 15 is obtained.

[0190] Example 16

[0191] The solid-state battery in Example 16 differs from that in Example 12 in that the bonding method in step (3) is different; the other steps are the same as in Example 12.

[0192] (1-2) Proceed according to step (1-2) of Example 12.

[0193] (3) Align the solid electrolyte membrane obtained in step (2) of Example 12 with the nano-silicon anode, and use isostatic pressing to hold the pressure at 60°C and 20MPa for 5 minutes to transfer the electrolyte membrane to the surface of the anode. Slowly peel off the PET film to obtain a composite anode with the solid electrolyte membrane transferred on it.

[0194] (4) Following step (4) of Example 12, the solid-state battery of Example 16 is obtained.

[0195] Example 17

[0196] The solid-state battery in Example 17 differs from that in Example 12 in that the bonding method in step (3) is different; the other steps are the same as in Example 12.

[0197] (1-2) Proceed according to step (1-2) of Example 12.

[0198] (3) Align the solid electrolyte membrane obtained in step (2) of Example 12 with the nano-silicon anode, and use a rolling method to hold the pressure at 60°C and 20MPa for 5 minutes to transfer the electrolyte membrane to the surface of the anode. Slowly peel off the PET film to obtain a composite anode with the solid electrolyte membrane transferred.

[0199] (4) Following step (4) of Example 12, the solid-state battery of Example 17 is obtained.

[0200] Example 18

[0201] The solid-state battery fabrication method of Example 18 includes the following steps:

[0202] (1) Polyisobutylene (viscosity-average molecular weight 2 million), SEBS block copolymer, C5 tackifying resin, DOP, and Irganox 1010 were mixed in a mass ratio of 60:30:8:2:0.5, heated to 150°C to melt, kept at that temperature for 2 hours, and added to a twin-screw extruder. The mixture was then co-extruded at 160°C and 500 rpm, and granulated to obtain the composite adhesive powder 1 of Example 18. The obtained composite adhesive powder 1 was dissolved in p-xylene and stirred thoroughly at 60°C to prepare a liquid 1 with a solid content of 5%. Polyisobutylene (viscosity-average molecular weight 2 million), SEBS block copolymer, C5 tackifying resin, DOP, and Irganox 1010 were mixed in a mass ratio of 30:60:8:2:0.5, and liquid 2 was prepared in the same manner.

[0203] (2) Mix LPSCl electrolyte and adhesive 1 at a mass ratio of 95:5, add p-xylene to adjust the solid content of the slurry, stir evenly and then coat it onto a PET film, vacuum dry at 80°C for 6 hours, and then press at 80°C and 100MPa for 3 minutes to obtain the positive electrode side solid electrolyte membrane of Example 18 with a thickness of 60μm.

[0204] (3) Align the solid electrolyte membrane on the positive electrode side obtained in step (2) with the NCM9 system positive electrode, and use isostatic pressing to hold the pressure at 60℃ and 20MPa for 5 minutes to transfer the solid electrolyte membrane on the positive electrode side to the positive electrode surface. Slowly peel off the PET film to obtain a composite positive electrode with the solid electrolyte membrane transferred on it.

[0205] (4) Mix LPSCl electrolyte and adhesive solution 2 at a mass ratio of 95:5, add p-xylene to adjust the solid content of the slurry, stir evenly and then coat it onto a PET film, vacuum dry at 80°C for 6 hours, and then press at 80°C and 100MPa for 3 minutes to obtain the negative electrode side solid electrolyte membrane of Example 18 with a thickness of 60μm.

[0206] (5) Align the solid electrolyte membrane on the negative electrode side obtained in step (4) with the nano-silicon negative electrode, and use isostatic pressing to hold the pressure at 60°C and 20MPa for 5 minutes to transfer the solid electrolyte membrane on the negative electrode side to the negative electrode surface. Slowly peel off the PET film to obtain a composite negative electrode with the solid electrolyte membrane transferred on it.

[0207] (6) Stack the composite positive electrode obtained in step (3) and the composite negative electrode obtained in step (5) so that the solid electrolyte membrane on the surface of the composite positive electrode comes into contact with the solid electrolyte membrane on the surface of the composite negative electrode. The battery is assembled under an assembly pressure of 4t to obtain the solid battery of Example 18.

[0208] Example 19

[0209] The solid-state battery in Example 19 differs from that in Example 18 in that the transfer temperature in step (5) is different; the other steps are the same as in Example 18.

[0210] (1-4) Proceed according to step (1-4) of Example 18.

[0211] (5) Align the solid electrolyte membrane on the negative electrode side obtained in step (4) with the nano-silicon negative electrode, and use isostatic pressing to hold the pressure at 40℃ and 20MPa for 5 minutes to transfer the solid electrolyte membrane on the negative electrode side to the negative electrode surface. Slowly peel off the PET film to obtain a composite negative electrode with the solid electrolyte membrane transferred on it.

[0212] (6) Following step (6) of Example 18, the solid-state battery of Example 19 is obtained.

[0213] Example 20

[0214] The solid-state battery in Example 20 differs from that in Example 18 in that the negative electrode material is different in step (5), while the other steps are the same as in Example 18:

[0215] (1-4) Proceed according to step (1-4) of Example 18.

[0216] (5) Align the solid electrolyte membrane on the negative electrode side obtained in step (4) with the SiC negative electrode, and use isostatic pressing to hold the pressure at 60°C and 20MPa for 5 minutes to transfer the solid electrolyte membrane on the negative electrode side to the surface of the negative electrode. Slowly peel off the PET film to obtain a composite negative electrode with the solid electrolyte membrane transferred on it.

[0217] (6) Following step (6) of Example 18, the solid-state battery of Example 20 is obtained.

[0218] Comparative Example 1

[0219] The solid-state battery of Comparative Example 1 differs from that of Example 1 in that the adhesive formulation in step (1) is different; the other steps are the same as those in Example 1.

[0220] (1) Polyisobutylene (viscosity average molecular weight 200,000), SEBS block copolymer, C5 tackifying resin, DOP, and Irganox 1010 are mixed in a mass ratio of 80:10:8:2:0.5 and the adhesive solution is prepared according to the method of step (1) in Example 1. However, the PIB content in this formulation is 80%, which exceeds the protection scope of claim 1.

[0221] (2-4) Following the steps (2-4) of Example 1, the solid-state battery of Comparative Example 1 was obtained.

[0222] Comparative Example 2

[0223] The solid-state battery of Comparative Example 2 differs from that of Example 1 in that the adhesive formulation in step (1) is different; the other steps are the same as those in Example 1.

[0224] (1) Polyisobutylene (viscosity average molecular weight 200,000), SEBS block copolymer, C5 tackifying resin, DOP, and Irganox 1010 are mixed in a mass ratio of 70:20:8:2:0.5 and the adhesive solution is prepared according to the method of step (1) in Example 1. However, the PIB content in this formulation is 70%, which exceeds the protection scope of claim 1.

[0225] (2-4) Following the steps (2-4) of Example 1, the solid-state battery of Comparative Example 2 was obtained.

[0226] Comparative Example 3

[0227] The solid-state battery of Comparative Example 3 differs from that of Example 1 in that the adhesive formulation in step (1) is different; the other steps are the same as those in Example 1.

[0228] (1) Polyisobutylene (viscosity average molecular weight 200,000), SEBS block copolymer, C5 tackifying resin, DOP, and Irganox 1010 are mixed in a mass ratio of 20:70:8:2:0.5 and the adhesive solution is prepared according to the method of step (1) in Example 1. However, the content of SEBS block copolymer in this formulation is 70%, which exceeds the protection scope of claim 1.

[0229] (2-4) Following the steps (2-4) of Example 1, the solid-state battery of Comparative Example 3 was obtained.

[0230] Comparative Example 4

[0231] The solid-state battery of Comparative Example 4 differs from that of Example 1 in that the adhesive formulation in step (1) is different; the other steps are the same as those in Example 1.

[0232] (1) Polyisobutylene (viscosity average molecular weight 200,000), SEBS block copolymer, C5 tackifying resin, DOP, and Irganox 1010 are mixed in a mass ratio of 10:80:8:2:0.5 and the adhesive solution is prepared according to the method of step (1) in Example 1. However, the content of SEBS block copolymer in this formulation is 80%, which exceeds the protection scope of claim 1.

[0233] (2-4) Following the steps (2-4) of Example 1, the solid-state battery of Comparative Example 4 was obtained.

[0234] Comparative Example 5

[0235] The solid-state battery of Comparative Example 5 differs from that of Example 9 in that the adhesive formulation in step (1) is different; the other steps are the same as those of Example 9.

[0236] (1) Polyisobutylene (viscosity average molecular weight 2 million), SEBS block copolymer, C5 tackifying resin, DOP, and Irganox 1010 are mixed in a mass ratio of 80:10:8:2:0.5 and the adhesive solution is prepared according to the method of step (1) in Example 9. However, the PIB content in this formulation is 80%, which exceeds the protection scope of claim 1.

[0237] (2-4) Following the steps (2-4) of Example 9, the solid-state battery of Comparative Example 5 was obtained.

[0238] Comparative Example 6

[0239] The solid-state battery of Comparative Example 6 differs from that of Example 9 in that the adhesive formulation in step (1) is different; the other steps are the same as those of Example 9.

[0240] (1) Polyisobutylene (viscosity average molecular weight 2 million), SEBS block copolymer, C5 tackifying resin, DOP, and Irganox 1010 are mixed in a mass ratio of 70:20:8:2:0.5 and the adhesive solution is prepared according to the method of step (1) in Example 9. However, the PIB content in this formulation is 70%, which exceeds the protection scope of claim 1.

[0241] (2-4) Following the steps (2-4) of Example 9, the solid-state battery of Comparative Example 6 was obtained.

[0242] Comparative Example 7

[0243] The solid-state battery of Comparative Example 7 differs from that of Example 9 in that the adhesive formulation in step (1) is different; the other steps are the same as those of Example 9.

[0244] (1) Polyisobutylene (viscosity average molecular weight 2 million), SEBS block copolymer, C5 tackifying resin, DOP, and Irganox 1010 are mixed in a mass ratio of 20:70:8:2:0.5 and the adhesive solution is prepared according to the method of step (1) in Example 9. However, the content of SEBS block copolymer in this formulation is 70%, which exceeds the protection scope of claim 1.

[0245] (2-4) Following the steps (2-4) of Example 9, the solid-state battery of Comparative Example 7 was obtained.

[0246] Comparative Example 8

[0247] The solid-state battery of Comparative Example 8 differs from that of Example 9 in that the adhesive formulation in step (1) is different; the other steps are the same as those of Example 9.

[0248] (1) Polyisobutylene (viscosity average molecular weight 2 million), SEBS block copolymer, C5 tackifying resin, DOP, and Irganox 1010 are mixed in a mass ratio of 10:80:8:2:0.5 and the adhesive solution is prepared according to the method of step (1) in Example 9. However, the content of SEBS block copolymer in this formulation is 80%, which exceeds the protection scope of claim 1.

[0249] (2-4) Following the steps (2-4) of Example 9, the solid-state battery of Comparative Example 8 was obtained.

[0250] Comparative Example 9

[0251] The solid-state battery of Comparative Example 9 differs from that of Example 1 in that the adhesive in step (1) is pure PIB, while the other steps are the same as those in Example 1:

[0252] (1) Polyisobutylene (viscosity-average molecular weight 200,000) was used alone as an adhesive, heated to 120°C to melt, kept at that temperature for 2 hours, added to a twin-screw extruder, and co-extruded at 160°C and 400 rpm, granulated to obtain the adhesive powder of Comparative Example 9. The obtained adhesive powder was dissolved in toluene and stirred thoroughly at 60°C to prepare an adhesive solution with a solid content of 5%.

[0253] (2) Mix LPSCl electrolyte and the adhesive solution obtained in step (1) at a mass ratio of 95:5, add toluene to adjust the solid content of the slurry, stir evenly and then coat it on a PET film, vacuum dry at 80°C for 6 hours, and then press at 80°C and 100MPa for 3 minutes to obtain the solid electrolyte film of Comparative Example 9 with a thickness of 100μm.

[0254] (3-4) Following the steps (3-4) of Example 1, the solid-state battery of Comparative Example 9 was obtained.

[0255] Comparative Example 10

[0256] The solid-state battery of Comparative Example 10 differs from that of Comparative Example 9 in that the adhesive in step (1) is a pure SEBS block copolymer, while the other steps are the same as those of Comparative Example 9:

[0257] (1) Using SEBS block copolymer alone as an adhesive, prepare adhesive solution according to the method of step (1) of Comparative Example 9.

[0258] (2-4) Following the steps of Comparative Example 9 (2-4), the solid-state battery of Comparative Example 10 was obtained.

[0259] Comparative Example 11

[0260] The solid-state battery of Comparative Example 11 differs from that of Comparative Example 9 in that the adhesive used in step (1) is SBR, while the other steps are the same as those of Comparative Example 9:

[0261] (1) Using SBR as an adhesive, prepare the adhesive solution according to the method of step (1) in Comparative Example 9.

[0262] (2-4) Following the steps of Comparative Example 9 (2-4), the solid-state battery of Comparative Example 11 was obtained.

[0263] Comparative Example 12

[0264] The solid-state battery of Comparative Example 12 differs from that of Comparative Example 9 in that the adhesive used in step (1) is H-NBR, while the other steps are the same as those of Comparative Example 9:

[0265] (1) Using H-NBR as an adhesive, prepare the adhesive solution according to the method of step (1) in Comparative Example 9.

[0266] (2-4) Following step (2-4) of Comparative Example 9, the solid-state battery of Comparative Example 12 was obtained.

[0267] Comparative Example 13

[0268] The solid-state battery of Comparative Example 13 differs from that of Example 9 in that the adhesive used in step (1) is SBR, while the other steps are the same as those of Example 9:

[0269] (1) SBR was used as an adhesive, heated to 120°C to melt, kept at that temperature for 2 hours, added to a twin-screw extruder, and co-extruded at 160°C and 500 rpm, and granulated to obtain the adhesive powder of Comparative Example 13. The obtained adhesive powder was dissolved in isobutyl isobutyrate and stirred thoroughly at 60°C to prepare an adhesive solution with a solid content of 5%.

[0270] (2) Mix LPSCl electrolyte and the adhesive solution obtained in step (1) at a mass ratio of 95:5, add isobutyl isobutyrate to adjust the solid content of the slurry, stir evenly and then coat it on a PET film, vacuum dry at 80°C for 6 hours, and then press at 80°C and 100MPa for 3 minutes to obtain the solid electrolyte film of Comparative Example 13 with a thickness of 100μm.

[0271] (3-4) Following the steps (3-4) of Example 9, a solid-state battery of Comparative Example 13 was obtained.

[0272] Comparative Example 14

[0273] The solid-state battery of Comparative Example 14 differs from that of Comparative Example 13 in that the adhesive used in step (1) is H-NBR, while the other steps are the same as those of Comparative Example 13:

[0274] (1) Using H-NBR as an adhesive, prepare the adhesive solution according to the method in step (1) of Comparative Example 13.

[0275] (2-4) Following the steps of Comparative Example 13 (2-4), the solid-state battery of Comparative Example 14 was obtained.

[0276] Comparative Example 15

[0277] The solid-state battery of Comparative Example 15 differs from that of Example 1 in that the transfer temperature in step (3) is different; the other steps are the same as those in Example 1.

[0278] (1-2) Proceed according to step (1-2) of Example 1.

[0279] (3) Align the solid electrolyte membrane obtained in step (2) of Example 1 with the NCM9 system positive electrode, heat it to 25°C, pressurize it to 20MPa and hold it for 5 minutes to transfer the electrolyte membrane to the surface of the positive electrode, and slowly peel off the PET film to obtain a composite positive electrode with the solid electrolyte membrane transferred.

[0280] (4) Following step (4) of Example 1, a solid-state battery of Comparative Example 15 was obtained.

[0281] Comparative Example 16

[0282] The solid-state battery of Comparative Example 16 differs from that of Example 1 in that the transfer temperature in step (3) is different; the other steps are the same as those in Example 1.

[0283] (1-2) Proceed according to step (1-2) of Example 1.

[0284] (3) Align the solid electrolyte membrane obtained in step (2) of Example 1 with the NCM9 system positive electrode, heat it to 150°C, pressurize it to 20MPa and hold it for 5 minutes to transfer the electrolyte membrane to the surface of the positive electrode, and slowly peel off the PET film to obtain a composite positive electrode with the solid electrolyte membrane transferred.

[0285] (4) Following step (4) of Example 1, a solid-state battery of Comparative Example 16 was obtained.

[0286] Comparative Example 17

[0287] The solid-state battery of Comparative Example 17 differs from that of Example 1 in that the molecular weight of PIB is different in step (1), where the viscosity-average molecular weight of polyisobutylene is 100,000. The other steps are the same as those in Example 1.

[0288] (1) Polyisobutylene (viscosity average molecular weight 100,000), SEBS block copolymer, C5 tackifying resin, DOP, and Irganox 1010 were mixed in a mass ratio of 60:30:8:2:0.5 and the adhesive solution was prepared according to the method of step (1) in Example 1.

[0289] (2-4) Following the steps (2-4) of Example 1, the solid-state battery of Comparative Example 17 was obtained.

[0290] Comparative Example 18

[0291] The solid-state battery of Comparative Example 18 differs from that of Example 1 in that the molecular weight of PIB is different in step (1), where the viscosity-average molecular weight of polyisobutylene is 4.2 million. The other steps are the same as those in Example 1.

[0292] (1) Polyisobutylene (viscosity average molecular weight 4.2 million), SEBS block copolymer, C5 tackifying resin, DOP, and Irganox 1010 were mixed in a mass ratio of 60:30:8:2:0.5 and the adhesive solution was prepared according to the method of step (1) in Example 1.

[0293] (2-4) Following the steps (2-4) of Example 1, a solid-state battery of Comparative Example 18 was obtained.

[0294] Table 3. Test results of the physicochemical properties of solid electrolyte membranes in Examples 1-20 and Comparative Examples 1-18

[0295]

[0296] Table 4. Performance test results of solid-state batteries in Examples 1-20 and Comparative Examples 1-18

[0297]

[0298] As shown in Tables 3 and 4, the composite adhesive provided by this invention exhibits excellent performance in terms of solid electrolyte membrane transfer quality, interfacial stability, and solid-state battery electrochemical performance. This composite adhesive effectively reduces interfacial defects and membrane damage, improves transfer success rate, and simultaneously achieves high ion conductivity, cycle stability, and low short-circuit risk. This demonstrates that the polyisobutylene and SEBS block copolymer composite system used in this invention effectively coordinates the relationship between adhesion, flexibility, film formation, and interfacial compatibility, thereby achieving excellent overall performance.

[0299] A comparison of Examples 1 to 4 with Comparative Examples 1 to 4 shows that when the ratio of polyisobutylene to SEBS block copolymer is within the range defined by this invention, the solid electrolyte membrane exhibits superior transfer integrity and interface quality, as well as better battery rate performance and cycle stability. However, when the ratio exceeds this range, interface defects, membrane damage, and short-circuit tendency all significantly increase. These results indicate that the polyisobutylene / SEBS block copolymer ratio range defined by this invention is not arbitrarily chosen, but rather a key condition for achieving high-quality transfer and excellent battery performance.

[0300] A comparison of Examples 9 to 12 with Comparative Examples 5 to 8 further demonstrates that the aforementioned ratio range also exhibits significant effects in negative electrode applications. In other words, the compounding ratios defined in this invention are applicable not only to the positive electrode interface construction but also to the negative electrode interface construction, achieving good film integrity, interface contact state, and overall battery performance on both electrode sides. This indicates that the ratio range described in this invention possesses universality and stability.

[0301] The comparison between Examples 1 and Examples 5 to 8 shows that the molecular weight of polyisobutylene has a significant impact on the performance of the composite adhesive. Within the testing scope of this invention, a suitable molecular weight of polyisobutylene can better balance interfacial adhesion, film toughness, and ion transport, thereby achieving a better balance in transfer quality, conductivity, cycle retention, and safety. This result demonstrates that the selection of the molecular weight of polyisobutylene in this invention has clear technical significance, and the same effect cannot be obtained simply by substitution.

[0302] The comparison of Examples 12, 13 to 15, and Comparative Examples 15 and 16 shows that the transfer temperature is a crucial process parameter for achieving the temperature-sensitive transfer effect of this invention. When the transfer temperature is within the range defined by this invention, the solid electrolyte membrane can smoothly complete the stable transfer from the carrier to the electrode surface, achieving good interface quality and battery performance. However, when the temperature is too low or too high, the transfer effect deteriorates significantly, further affecting cycle stability and short-circuit performance. This result indicates that the temperature range defined by this invention is necessary for effectively controlling the pick-up and release of the adhesive.

[0303] A comparison of Examples 12, 16, and 17 shows that the bonding method significantly impacts the interface state and subsequent battery performance. Compared to flatbed bonding and roll bonding, isostatic bonding is more conducive to forming uniform, dense, and complete interface contacts, thereby further improving rate performance, cycle stability, and reducing interface defects. This result demonstrates a good match between the bonding process and the material system used in this invention, further amplifying the technical effects of the composite adhesive of this invention.

[0304] A comparison of Examples 1, 12, and 18 shows that differentiated designs for the positive and negative electrode sides, along with the construction of a dual-sided interface structure, significantly improves interface density, reduces short-circuit risk, and maintains excellent cycle performance under lower test pressures. These results demonstrate that the present invention not only has significant effects in single-sided interface construction but also further enhances overall solid-state battery performance through synergistic positive and negative electrode design, exhibiting strong systemic advantages.

[0305] The comparison of Examples 18 to 20 shows that, based on the double-sided transfer structure, by adjusting the process conditions on the negative electrode side or changing the negative electrode material, the system of the present invention can still maintain good film integrity and low short-circuit risk, indicating that the composite adhesive system of the present invention has good process adaptability and material compatibility. In particular, it can still maintain excellent interface quality under different negative electrode conditions, further proving that the solution of the present invention is not limited to a single electrode system, but has a wide range of applications.

[0306] The comparison between Examples 1 and Comparative Examples 9 to 12, and between Example 12 and Comparative Examples 13 and 14, shows that using polyisobutylene alone, using SEBS block copolymer alone, or using traditional adhesives such as SBR and H-NBR, cannot simultaneously achieve the transfer integrity, interfacial density, electrochemical performance, and safety performance achieved by this invention. In other words, this invention is not a simple replacement of existing adhesive materials, nor is it a linear superposition of the properties of each component. Rather, it is the synergistic effect formed by polyisobutylene and SEBS block copolymer under specific ratios and specific process conditions that achieves comprehensive technical effects superior to single-component and traditional adhesive systems.

[0307] In summary, this invention significantly improves the transfer behavior and interface construction quality of solid electrolyte membranes by synergistically optimizing factors such as the polyisobutylene / SEBS block copolymer ratio, polyisobutylene molecular weight, transfer temperature, and bonding process. It further enhances the rate performance, cycle stability, and safety of solid-state batteries, fully demonstrating that the present invention has outstanding substantive features and significant progress.

[0308] The specific embodiments described herein are merely illustrative of the spirit of the invention. Those skilled in the art to which this invention pertains may make various modifications or additions to the described specific embodiments or use similar methods to substitute them without departing from the spirit of the invention or exceeding the scope defined by the appended claims.

Claims

1. A method for transferring a solid electrolyte membrane, characterized in that, Includes the following steps: A) Provide a component to be transferred, the component to be transferred including a carrier and a solid electrolyte membrane formed on the surface of the carrier; stack the component to be transferred with an electrode, with the solid electrolyte membrane facing the surface of the electrode, and apply pressure at 40-100°C to make the solid electrolyte membrane adhere to the surface of the electrode; B) Peel off the carrier to transfer the solid electrolyte membrane from the carrier to the electrode surface, thereby obtaining an electrode with a solid electrolyte membrane on its surface; The method for preparing the component to be transferred includes the following steps: a) A slurry is prepared by mixing a composite adhesive, a solid electrolyte, and a solvent, wherein the raw materials of the composite adhesive include polyisobutylene and a styrene-ethylene-butene-styrene block copolymer, wherein the content of polyisobutylene is 30-60 wt%, the content of the styrene-ethylene-butene-styrene block copolymer is 20-60 wt%, and the viscosity-average molecular weight of the polyisobutylene is 200,000-4,000,000 Da; b) The slurry is coated onto a carrier and dried to obtain the component to be transferred.

2. The transfer method according to claim 1, characterized in that, In step A), pressure is applied using one or more of the following methods: flat plate pressing, roller pressing, and isostatic pressing. And / or, in step A), the pressure conditions are: pressure 0.5-100 MPa, pressure holding time 1-30 min.

3. The transfer method according to claim 1, characterized in that, Step B) is followed by an annealing process; the annealing process is carried out in an inert atmosphere, the annealing temperature is 20-95℃, and the annealing time is 10-120min.

4. The transfer method according to claim 1, characterized in that, When the electrode is a positive electrode, the mass ratio of polyisobutylene to styrene-ethylene-butene-styrene block copolymer in the composite adhesive of the solid electrolyte membrane to be transferred is 60:30 to 30:

60. And / or, when the electrode is a negative electrode, the mass ratio of polyisobutylene to styrene-ethylene-butene-styrene block copolymer in the composite adhesive of the solid electrolyte membrane to be transferred is 60:30 to 30:

60.

5. The transfer method according to claim 1, characterized in that, The solid electrolyte is selected from one or more of sulfide electrolytes, oxide electrolytes, and halide electrolytes.

6. The transfer method according to claim 1, characterized in that, The electrode is a positive electrode and / or a negative electrode; The active material of the positive electrode is selected from one or more of lithium nickel cobalt manganese oxide, lithium nickel cobalt aluminum oxide, and lithium-rich manganese-based positive electrode materials; And / or, the active material of the negative electrode is selected from one or more of graphite, silicon carbide, silicon oxide, silicon, lithium metal or lithium silicon alloy.

7. The transfer method according to claim 1, characterized in that, The raw materials of the composite adhesive also include one or more of the following: tackifying resin, plasticizer, and antioxidant; The tackifying resin accounts for 5-15 wt% of the total weight of the composite adhesive. And / or, the plasticizer accounts for 0-10 wt% of the total weight of the composite adhesive; And / or, the antioxidant accounts for 0.1-1 wt% of the total weight of the composite adhesive.

8. The transfer method according to claim 1, characterized in that, The preparation method of the composite adhesive includes the following steps: Polyisobutylene, styrene-ethylene-butene-styrene block copolymer, tackifying resin, plasticizer, and antioxidant are mixed and heated to melt, kept at the temperature for 1-3 hours, added to a twin-screw extruder, and co-extruded at 155-165℃ and 350-550rpm, and granulated to obtain the composite adhesive.

9. An electrode with a solid electrolyte membrane on its surface, characterized in that, It is prepared by the transfer method as described in any one of claims 1-8.

10. A solid-state battery, characterized in that, It contains a positive electrode and a negative electrode; The positive electrode is the electrode with a solid electrolyte membrane on its surface as described in claim 9; And / or, the negative electrode is the electrode with a solid electrolyte membrane on its surface as described in claim 9; When either the positive electrode or the negative electrode is an electrode with a solid electrolyte membrane on its surface, the solid electrolyte membrane is located between the positive electrode and the negative electrode; When both the positive electrode and the negative electrode are electrodes with a solid electrolyte membrane on their surface as described in claim 9, the solid electrolyte membranes on their surfaces are arranged opposite each other and at least partially in contact.

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