An integrated electrode and a preparation method and application thereof

Abstract

The application discloses an integrated electrode and a preparation method and application thereof. The integrated electrode comprises a first electrode active layer, a porous adhesive film layer and a second electrode active layer which are stacked in sequence. The porous adhesive film layer is formed by solvent evaporation induced phase separation of a polymer-based colloidal system. The polymer-based colloidal system comprises a polymer and a solvent. The polymer comprises at least one of a polyamide, a polyurethane, a polyurea, a polythiourea or a polyvinylidene fluoride polymer. The application forms the porous adhesive film layer by solvent evaporation induced phase separation, realizes ion transmission and electronic isolation between adjacent electrode active layers, and has a continuous interface and reduces independent bonding interfaces. The application can effectively improve structural consistency and reduce interface impedance. The integrated electrode formed by the application can maintain structural integrity, can exist as an independent electrochemical unit without relying on a current collector, can be used for preparing an integrated battery, and can realize patterning, modular interconnection and battery-circuit-substrate integration.

Description

Technical Field

[0001] This invention belongs to the field of electrochemical device technology, and particularly relates to an integrated electrode, its preparation method and application. Background Technology

[0002] With the development of flexible electronics, wearable devices, and low-power integrated systems, new requirements have been placed on electrochemical energy devices, including lightweighting, integration, printability, and patternable integration. Traditional lithium-ion batteries typically employ a stacking assembly method of pre-fabricated separators and independent electrode sheets, and are fabricated through processes such as stacking / winding, soldering, and liquid injection encapsulation. This type of process is complex, involves a large number of interfaces, and exhibits uneven local interface contact, making it difficult to adapt to the needs of continuous, patterned, or direct manufacturing on curved / non-flat substrates.

[0003] To achieve structural simplification and process integration, existing technologies have attempted to introduce gel-like or polymer layers on the electrode surface to replace traditional isolation structures or realize quasi-solid / solid electrolyte systems. However, such solutions often rely on pre-porous materials, solvent-free bath treatment, or thermally induced pore-forming processes, and there are still shortcomings in interlayer bonding, pore structure uniformity, and compatibility with continuous printing manufacturing. At the same time, when performing high-density integration of power and circuits on supports with circuit traces, traditional battery form factors are difficult to match irregular remaining space, resulting in low space utilization and limited system integration. Summary of the Invention

[0004] In order to overcome at least one of the problems existing in the prior art, one of the objectives of the present invention is to provide an integrated electrode that does not require an additional pore-forming step, can spontaneously form a porous film layer by inducing phase separation through solvent evaporation during the drying film formation process, and can be integrated with the upper and lower electrode active layers in situ to form a composite structure without independent bonding interfaces, so as to achieve a highly consistent stacked structure of batteries and related electrochemical devices.

[0005] The second objective of this invention is to provide a method for preparing the aforementioned integrated electrode.

[0006] The third objective of this invention is to provide an integrated battery.

[0007] The fourth objective of this invention is to provide an electronic device.

[0008] The fifth objective of this invention is to provide an application of the aforementioned integrated electrode, integrated battery, or electronic device.

[0009] To achieve the above objectives, the technical solution adopted by the present invention is as follows: A first aspect of the present invention provides an integrated electrode comprising a first electrode active layer, a porous adhesive film layer, and a second electrode active layer stacked sequentially; the porous adhesive film layer is formed by solvent evaporation-induced phase separation of a polymer-based colloidal system; the polymer-based colloidal system comprises a polymer and a solvent; the polymer comprises at least one of polyamide, polyurethane, polyurea, polythiourea, or polyvinylidene fluoride polymers.

[0010] In some embodiments of the present invention, the first electrode active layer, the porous adhesive film layer, and the second electrode active layer are constructed by a layer-by-layer continuous film formation method to form an integrated electrochemical structure without independent bonding interfaces.

[0011] In some embodiments of the present invention, the porous adhesive film layer is not formed by bonding pre-fabricated independent films.

[0012] In some embodiments of the present invention, the polymer is selected from polyamides; more specifically, it may be polyamide 1010.

[0013] In some embodiments of the present invention, the solvent in the polymer-based colloidal system is a volatile solvent and can disperse the polymer to form a polymer-based colloidal system.

[0014] In some embodiments of the present invention, the solvent in the polymer-based colloidal system includes formic acid and / or chloroform; in some specific embodiments of the present invention, the solvent is a mixed solvent of formic acid and chloroform; in some more specific embodiments of the present invention, the mass ratio of formic acid to chloroform is 1:(0.5~1.5).

[0015] In some embodiments of the present invention, the polymer concentration in the polymer-based colloidal system is 5-20 wt%; in some specific embodiments of the present invention, the polymer concentration in the polymer-based colloidal system is 10-14 wt%.

[0016] In some embodiments of the present invention, the temperature for solvent evaporation-induced phase separation is 25~35°C.

[0017] In some embodiments of the present invention, the humidity of the solvent evaporation-induced phase separation is 10-30%.

[0018] In some embodiments of the present invention, the porous film layer has a porous structure.

[0019] In some embodiments of the present invention, the porous structure is a connecting channel that extends through the thickness direction of the porous adhesive film layer.

[0020] In some embodiments of the present invention, the average pore size of the porous film layer is 0.05 μm to 10 μm, specifically any value or a range between any two of 0.05 μm, 0.1 μm, 0.3 μm, 0.5 μm, 0.7 μm, 1 μm, 3 μm, 5 μm, 7 μm or 10 μm; the average porosity is 20% to 85%, specifically any value or a range between any two of 20%, 30%, 40%, 50%, 60%, 70%, 80% or 85%.

[0021] In some specific embodiments of the present invention, the average pore size of the porous adhesive film layer is 0.1~0.3μm, and the average porosity is 50~70%.

[0022] In some embodiments of the present invention, the porous structure of the porous film layer is formed spontaneously by a solvent evaporation-induced phase separation process without undergoing non-solvent bath treatment and / or thermally induced pore-forming steps during the formation process.

[0023] In some embodiments of the present invention, the porous film layer can simultaneously achieve mechanical bonding, ion transport, and electrolyte storage between adjacent electrode active layers. Utilizing the porous film layer provided by the present invention can effectively improve interlayer bonding stability and electrolyte wetting consistency.

[0024] In some embodiments of the present invention, the first electrode active layer is a positive electrode active layer or a negative electrode active layer, and the second electrode active layer is a negative electrode active layer or a positive electrode active layer corresponding to the first electrode active layer.

[0025] In some embodiments of the present invention, the positive electrode active layer comprises a positive electrode active material, which includes at least one of lithium iron phosphate, layered oxide positive electrode material, or spinel-type positive electrode material.

[0026] In some embodiments of the present invention, the negative electrode active layer comprises a negative electrode active material, which includes at least one of lithium titanate, graphite, or hard carbon material.

[0027] A second aspect of the present invention provides a method for preparing an integrated electrode as described in the first aspect of the present invention, comprising the following steps: preparing a first electrode active layer on the surface of a temporary substrate; applying the polymer solution to the surface of the first electrode active layer away from the temporary substrate, and forming the porous film layer by solvent evaporation-induced phase separation; preparing a second electrode active layer on the surface of the porous film layer away from the first electrode active layer; and removing the temporary substrate to obtain the integrated electrode.

[0028] The first electrode active layer, the porous film layer, and the second electrode active layer of this invention form an integral self-supporting structure through in-situ continuous film deposition. This structure can be completely peeled off from the temporary substrate surface while maintaining its structural integrity, existing as an independent electrochemical unit without relying on a current collector. The porous film layer of this invention spontaneously forms pores through solvent evaporation-induced phase separation, eliminating the need for additional pore-forming steps such as non-solvent baths or thermal induction, simplifying the process and providing good adaptability for continuous manufacturing.

[0029] In some embodiments of the present invention, the temporary substrate includes at least one of a glass substrate, a silicon wafer, or a release film.

[0030] In some embodiments of the present invention, the integrated electrode can be used to fabricate an integrated battery, such as a coin cell. Specifically, the desired electrode shape can be obtained by cutting or punching, and then assembled to form an integrated battery, such as a coin cell.

[0031] A third aspect of the present invention provides an integrated battery comprising the integrated electrode described in the first aspect of the present invention.

[0032] In some embodiments of the present invention, the integrated battery is a button battery, which is assembled using the integrated electrode, positive electrode shell and negative electrode shell.

[0033] In some embodiments of the present invention, the integrated battery includes a battery substrate and a battery cell disposed on the surface of the battery substrate; the battery cell includes a first conductive layer, the integrated electrode, and a second conductive layer stacked sequentially.

[0034] The integrated electrode of the present invention can be formed by peeling to form a self-supporting structure and then assembling it to form an integrated battery, such as a button battery; or it can be constructed by layer-by-layer continuous film formation without removing the substrate.

[0035] In some embodiments of the present invention, the first electrode active layer of the integrated electrode is in contact with the first conductive layer, and the second electrode active layer is in contact with the second conductive layer.

[0036] In some embodiments of the present invention, the battery substrate is a planar substrate, a curved substrate, or a non-flat three-dimensional structure substrate. The integrated electrode of the present invention supports direct printing and fabrication on planar, curved, and non-flat three-dimensional structure substrates, making it suitable for flexible, irregularly shaped, and space-constrained scenarios.

[0037] In some embodiments of the present invention, the battery substrate is made of at least one of wood, polymer, glass, ceramic, stone or brick.

[0038] In some embodiments of the present invention, the first conductive layer is used to realize the electrical connection between the first electrode active layer and the external circuit, and the second conductive layer is used to realize the electrical connection between the second electrode active layer and the external circuit.

[0039] In some embodiments of the present invention, the first conductive layer and / or the second conductive layer are formed by printing.

[0040] In some embodiments of the present invention, the raw materials for preparing the first conductive layer and / or the second conductive layer include conductive agents.

[0041] In some embodiments of the present invention, the conductive agent comprises carbon materials and / or metallic conductive fillers.

[0042] In some embodiments of the present invention, the carbon material includes at least one of carbon black, graphite, graphene, or carbon nanotubes.

[0043] In some embodiments of the present invention, the metal conductive filler includes at least one of silver, copper, nickel, or alloys thereof.

[0044] In some embodiments of the present invention, the shape of the metal conductive filler includes at least one of particles, flakes, or fibers.

[0045] In some embodiments of the present invention, the first conductive layer and / or the second conductive layer are composite conductive layers; the composite conductive layer includes a carbon-containing conductive layer and a metal conductive layer stacked sequentially; the carbon-containing conductive layer contains carbon material; the metal conductive layer contains metal conductive filler; specifically, the carbon material and / or metal conductive filler mentioned above can be used.

[0046] In some embodiments of the present invention, the first conductive layer and / or the second conductive layer have reserved terminal extension areas for external electrical connection.

[0047] In some embodiments of the present invention, an electrolyte is further disposed in the porous adhesive film layer of the integrated electrode.

[0048] In some embodiments of the present invention, the electrolyte includes a liquid electrolyte or a gel electrolyte.

[0049] In some embodiments of the present invention, the electrolyte comprises a lithium salt and an electrolytic solvent; in some specific embodiments of the present invention, the lithium salt is lithium hexafluorophosphate; the electrolytic solvent is ethylene carbonate and dimethyl carbonate, more specifically, the volume ratio of ethylene carbonate to dimethyl carbonate is 1:(0.5~1.5).

[0050] In some embodiments of the present invention, the lithium salt concentration in the electrolyte is 0.5~1.5 mol / L.

[0051] In some embodiments of the present invention, the integrated battery includes an integrated lithium-ion battery.

[0052] In some embodiments of the present invention, the battery substrate includes a battery functional area, and the battery cell is disposed within the battery functional area; the planar projection pattern of the battery functional area includes at least one of the following: strip shape, snake shape, wave shape, spiral shape, grid shape, ring shape, text logo shape, or graphic logo shape.

[0053] In some embodiments of the present invention, the planar projection pattern of the battery functional area is an irregular shape.

[0054] In some embodiments of the present invention, the number of battery cells is one or more; the plurality of battery cells are connected in series and / or in parallel.

[0055] In some embodiments of the present invention, the plurality of battery cells are connected by a conductive interconnection structure.

[0056] The battery of the present invention supports patterned battery functional areas and multi-cell series-parallel interconnection, which is beneficial for on-demand customization of voltage or capacity and modular integration.

[0057] A fourth aspect of the present invention provides an electronic device comprising a battery module and a functional module integrated on the same substrate; the battery module comprising the integrated battery described in the third aspect of the present invention; and the functional module comprising conductive lines and / or interconnection structures for electronic components.

[0058] In some embodiments of the present invention, the conductive interconnect structure includes printed conductive lines and / or pads.

[0059] In some embodiments of the present invention, the substrate of the electronic device includes a battery functional area and a circuit functional area, the battery module is disposed in the battery functional area, and the functional module is disposed in the circuit functional area.

[0060] In some embodiments of the present invention, the substrate of the electronic device may be the battery substrate of the integrated battery.

[0061] In some embodiments of the present invention, the battery functional area and the circuit functional area do not overlap at least partially in planar projection; they may be partially non-overlapping or completely non-overlapping.

[0062] The electronic device of the present invention supports printing batteries in a reserved area of ​​a substrate with circuit functional areas, and is particularly suitable for power supply and circuit integration on the same substrate as a carrier such as flexible PCB, thereby improving space utilization and system integration.

[0063] In some embodiments of the present invention, the first conductive layer and / or the second conductive layer extend to form electrical connection terminals and are electrically connected to the conductive interconnection structure within the circuit functional area.

[0064] In some embodiments of the present invention, the substrate of the electronic device is a printed circuit board (PCB); specifically, it may be a flexible printed circuit board (FPCB).

[0065] The fifth aspect of the present invention provides an application of an integrated electrode as described in the first aspect of the present invention, or an integrated battery as described in the third aspect of the present invention, or an electronic device as described in the fourth aspect of the present invention in the fabrication of flexible electronic devices, wearable electronic devices, or micro energy storage systems.

[0066] The beneficial effects of this invention are: This invention forms a porous film layer by solvent evaporation-induced phase separation, which enables ion transport and electronic isolation between adjacent electrode active layers. Furthermore, the porous film layer and the first and second electrode active layers are constructed through in-situ continuous film formation, resulting in continuous interfaces and reduced independent bonding interfaces. This effectively improves structural consistency and reduces interfacial impedance. The resulting integrated electrode maintains structural integrity and can exist as an independent electrochemical unit without relying on current collectors. It can also be used to fabricate integrated batteries and achieve patterned, modular interconnection and battery-circuit integration on the same substrate. Attached Figure Description

[0067] Figure 1 This is a schematic diagram of the integrated lithium-ion battery in Example 2.

[0068] Figure 2 This is a schematic diagram of the battery functional area of ​​the integrated lithium-ion battery in Example 6.

[0069] Figure 3 This is a schematic diagram of the series and parallel connection structure between the battery cells of the integrated lithium-ion battery in Example 6.

[0070] Figure 4 This is a schematic diagram of the circuit functional area and reserved battery functional area of ​​the electronic device in Example 7.

[0071] Figure 5 This is a schematic diagram of the reserved battery functional area of ​​the electronic device in Example 7.

[0072] Figure 6 This is a physical image of the integrated electrode in Example 1.

[0073] Figure 7 This is a cross-sectional scanning electron microscope image of the integrated electrode in Example 1.

[0074] Figure 8This is a cycle curve diagram of the integrated battery in Example 1. Detailed Implementation

[0075] The following specific embodiments further illustrate the content of the present invention in detail. It should also be understood that the following embodiments are only for further explanation of the present invention and should not be construed as limiting the scope of protection of the present invention. Non-essential improvements and adjustments made by those skilled in the art based on the principles described herein are all within the scope of protection of the present invention. The specific process parameters, etc., in the following examples are merely examples within a suitable range; that is, those skilled in the art can make selections within a suitable range based on the description herein, and are not intended to be limited to the specific data in the examples below. Unless otherwise specified, the raw materials, reagents, or apparatus used in the following embodiments and comparative examples can be obtained from conventional commercial sources or by existing known methods.

[0076] Terminology Explanation: Substrate: The support structure that carries the printed / coated laminate structure. It can be the substrate for the final device or a temporary substrate.

[0077] Temporary substrate: A substrate used to prepare a self-supporting structure after peeling, such as a glass substrate, silicon wafer, or release film.

[0078] Porous film layer: A polymer film formed by a printable colloidal film-forming system, which spontaneously forms a porous structure through solvent evaporation-induced phase separation during the drying film-forming process; In embodiments of the present invention, the porous film layer is formed without non-solvent bath treatment and / or thermally induced pore-forming steps.

[0079] Circuit functional area / battery functional area: The areas on the same substrate used to form the circuit interconnect structure and the battery stack structure, respectively. The two do not overlap or do not overlap at all in the plane projection; the battery functional area is the area reserved relative to the circuit functional area.

[0080] Example 1 An integrated electrode and an integrated battery are disclosed, wherein the integrated electrode is formed by constructing and integrally peeling off a temporary substrate, and the specific fabrication steps are as follows: 1) Temporary substrate: Select a glass substrate or silicon wafer as a temporary substrate, and clean and dry it.

[0081] 2) Formation of the first electrode active layer: The first electrode active layer (positive electrode active layer) slurry is coated on a temporary substrate and dried at 85°C. The first electrode active layer slurry is prepared by the active material lithium iron phosphate (LFP), the conductive agent SuperP and the polyvinylidene fluoride binder in a mass ratio of 8:1:1.

[0082] 3) Formation of a porous film layer (polyamide PA film): A polymer colloidal film-forming system is coated onto the active layer of the first electrode. During the drying process, a porous film layer is spontaneously formed through solvent evaporation-induced phase separation. The film slurry is polyamide 1010 dissolved in a mixed solution of formic acid and chloroform, with a polymer concentration of 12% and a formic acid to chloroform ratio of 1:1. The drying process is carried out under controlled conditions (temperature 30℃, humidity 10~30%), allowing the colloidal film-forming system to undergo solvent evaporation-induced phase separation and spontaneously form a porous structure during the drying process. The formation process does not involve non-solvent bath treatment or thermally induced pore formation steps; the pore structure consists of interconnected channels extending throughout the thickness direction, with an average pore diameter of 0.16 μm and an average porosity of 57%.

[0083] 4) Formation of the second electrode active layer: The second electrode active layer (negative electrode active layer) slurry is coated onto the porous adhesive film layer and dried. The first electrode active layer slurry is prepared by the active material lithium titanate (LTO), the conductive agent SuperP and the polyvinylidene fluoride binder in a mass ratio of 8:1:1.

[0084] 5) Overall peeling: The obtained three-layer stacked structure is peeled off from the temporary substrate to obtain an integral self-supporting integrated electrode structure, denoted as LFP-PA-LTO structure.

[0085] The specific fabrication steps of an integrated battery are as follows: The integrated electrode prepared above is cut into sheet-like units and injected with electrolyte (the electrolyte is a 1.0M lithium hexafluorophosphate solution, and the solvent is ethylene carbonate and dimethyl carbonate in a volume ratio of 1:1). The porous film layer forms a liquid-containing porous colloidal structure and is assembled into a button cell, which is the integrated cell in this example.

[0086] Example 2 A schematic diagram of an integrated lithium-ion battery based on multilayer printing is shown below. Figure 1 It includes, in sequence, a substrate, a first conductive layer, a first electrode active layer, a porous adhesive film layer, a second electrode active layer, and a second conductive layer.

[0087] The specific preparation method of the above-mentioned integrated lithium-ion battery is as follows: 1) Substrate preparation: Select polyethylene terephthalate (PET) as the substrate, clean and dry it.

[0088] 2) Printing of the first conductive layer: The first conductive layer is formed on the substrate by screen printing. The first conductive layer is printed into a film using carbon black conductive paste, and terminal extension areas are reserved as needed for external electrical connections.

[0089] 3) Formation of the first electrode active layer: The first electrode active layer (positive electrode active layer) is printed on the first conductive layer. The electrode active layer is formed by printing the first electrode active layer paste and drying it at 85°C. The first electrode active layer paste is prepared by the active material lithium iron phosphate, the conductive agent SuperP and the polyvinylidene fluoride binder in a mass ratio of 8:1:1.

[0090] 4) Formation of a porous film layer (polyamide film): A polymer colloidal film-forming system is coated onto the active layer of the first electrode. During the drying process, a porous film layer is spontaneously formed through solvent evaporation-induced phase separation. The film slurry is polyamide 1010 dissolved in a mixed solution of formic acid and chloroform, with a polymer concentration of 12% and a formic acid to chloroform ratio of 1:1. The drying process is carried out under controlled conditions (temperature around 30℃, humidity between 10-30%), allowing the colloidal film-forming system to undergo solvent evaporation-induced phase separation and spontaneously form a porous structure during the drying process. The formation process does not involve non-solvent bath treatment or thermally induced pore formation steps; the pore structure consists of interconnected channels extending throughout the thickness direction, with an average pore diameter of 0.16 μm and a porosity of 57%.

[0091] 5) Formation of the second electrode active layer: The second electrode active layer (negative electrode active layer) slurry is coated onto the porous adhesive film layer and dried. The first electrode active layer slurry is prepared by the active material lithium titanate, the conductive agent SuperP and the polyvinylidene fluoride binder in a mass ratio of 8:1:1.

[0092] 6) Printing of the second conductive layer: Print the second conductive layer on the active layer of the second electrode. The second conductive layer is printed into a film using carbon black conductive paste, and the terminal extension area can also be reserved.

[0093] 7) Introduction of electrolyte (the electrolyte is a 1.0M lithium hexafluorophosphate solution, and the solvent is ethylene carbonate and dimethyl carbonate in a volume ratio of 1:1): The electrolyte is introduced into the battery stack structure. The electrolyte is stored in the pores of the porous film layer and forms a continuous ion transport channel, thereby obtaining an integrated lithium-ion battery.

[0094] Example 3 An integrated lithium-ion battery is directly printed and constructed on a curved or non-flat three-dimensional substrate. The specific fabrication steps are as follows: Curved ceramic parts or non-flat wooden parts are selected as the three-dimensional structural base; Within a selected area on the substrate surface, a first conductive layer, a first electrode active layer, a porous adhesive film layer, a second electrode active layer, and a second conductive layer are sequentially formed according to the steps of Example 2 to obtain the integrated lithium-ion battery of this example.

[0095] Since the porous adhesive film layer and the electrode active layer can be continuously formed in situ and achieve mechanical bonding and electrolyte storage, the laminated structure can still maintain continuity on curved or uneven substrates, meeting the need to directly construct power sources in space-constrained or specific surface locations.

[0096] Example 4 An integrated lithium-ion battery with enhanced conductivity differs from Example 2 in that both the first and second conductive layers in this example are enhanced in conductivity, i.e., silver powder is mixed into the carbon black conductive paste of Example 2 to form a composite conductive paste for printing; other conditions are the same as in Example 2.

[0097] Example 5 An integrated lithium-ion battery with enhanced conductivity differs from Example 2 in that both the first and second conductive layers in this example are enhanced in conductivity. Specifically, the carbon black conductive layer of Example 2 is printed first, and then silver paste is printed on it to form a double-layer conductive structure, thereby reducing the surface resistance and improving the reliability of external leads. Other conditions are the same as in Example 2.

[0098] Example 6 An integrated lithium-ion battery is disclosed, wherein the functional areas of the battery are patterned and multiple battery cells are interconnected in series and parallel. The specific fabrication steps are as follows: Polyethylene terephthalate (PET) is selected as the substrate, and battery functional areas are printed on the substrate according to a predetermined patterned path. A schematic diagram of the battery functional areas is shown below. Figure 2 As shown, A represents a strip shape, B a serpentine shape, C a grid shape, D a ring shape, E a text label, and F a graphic label; multiple battery cells are formed on the same substrate. The battery cells are prepared according to the lithium-ion battery method in Example 2.

[0099] The battery cells are connected in series or parallel via printed conductive interconnect structures, which are formed from carbon black conductive paste. Schematic diagrams of the series and parallel connections between the battery cells are shown below. Figure 3 As shown, A is a series structure and B is a parallel structure, thus obtaining a modular printed battery structure with customizable output voltage and capacity.

[0100] Example 7 An electronic device in which the battery and circuit functional areas are integrated on the same substrate (an irregular area is reserved on the flexible PCB), the specific fabrication steps are as follows: 1) Substrate and Circuit Functional Areas: A flexible printed circuit board (FPCB) is selected as the substrate, and circuit functional areas are pre-formed on it (see...). Figure 4 In section A), the circuit functional area includes printed conductive lines, pads, and interconnection structures for electronic components.

[0101] 2) Reserved Battery Functional Area: After the circuit layout is completed, there is remaining space between conductive lines on the FPCB, which serves as a reserved battery functional area. This reserved battery functional area has an irregular shape (see...). Figure 5 This irregularly shaped area is selected as the reserved battery functional area. The reserved battery functional area and the circuit functional area do not overlap in the planar projection (see...). Figure 4 (B in the middle).

[0102] 3) Printing the battery in the reserved battery functional area: In the reserved battery functional area, the first conductive layer, the first electrode active layer, the porous adhesive film layer, the second electrode active layer and the second conductive layer are continuously printed layer by layer according to the method of Example 2; wherein the first conductive layer and the second conductive layer extend to form electrical connection terminals.

[0103] 4) Electrical Connection Integration: Electrical connection terminals are electrically connected to the pads and conductive lines of the circuit functional area, enabling the printed battery and printed circuit to be integrated on the same substrate. This integration method can significantly improve space utilization and reduce system-level assembly complexity.

[0104] Performance testing 1) Morphological characterization: The electrode and battery structures prepared in each embodiment were characterized by scanning electron microscopy (SEM).

[0105] 2) Capacity and cycle performance: Test conditions are: 25℃, charge and discharge at 0.5C / 0.5C rate, cutoff voltage range is 1.0~2.4V.

[0106] 3) Resistance: Use a digital multimeter (resistance range) to test the resistance of the first conductive layer of the battery. Fix two probes at two points on the conductive layer with a distance of 5cm between them. After the value stabilizes, read the measured resistance value. Repeat the measurement 3 times at the same location and take the average value.

[0107] Figure 6 This is a physical image of the integrated electrode in Example 1; Figure 7 This is a cross-sectional scanning electron microscope (SEM) image of the integrated electrode in Example 1. From... Figure 6 and Figure 7 As can be seen, the method of Example 1 can be used to prepare a self-supporting integrated electrode with a complete structure, which can exist as an independent electrochemical unit without relying on the current collector.

[0108] Figure 8 This is a cycle curve diagram of the integrated battery in Example 1. From Figure 8 As can be seen, the battery in Example 1 has an initial discharge capacity of 88 mAh·g at 0.5C. -1 It can still maintain 73mAh·g after 50 cycles. -1The coulombic efficiency (CE) remained close to 100% after 50 cycles, demonstrating good capacity performance and cycle stability. Electrochemical tests showed that the coin cell fabricated with the integrated electrode of Example 1 could achieve lithium-ion transport and obtained stable electrochemical performance.

[0109] Table 1 shows the average resistance of the first conductive layer in Examples 2 and 4-5. As can be seen from Table 1, compared with Example 2, the average resistance of Examples 4-5 decreased significantly after conductivity enhancement, and the conductivity was significantly improved.

[0110] Table 1. Average resistance of the first conductive layer in batteries of Examples 2, 4, and 5.

[0111] This invention introduces a printable, film-forming porous film layer between adjacent electrode active layers. This porous film layer spontaneously forms a porous structure through solvent evaporation-induced phase separation during the drying process, enabling lithium-ion transport between adjacent electrode active layers and preventing direct electronic contact between them. A continuous, layer-by-layer film formation method is used to create an integrated electrochemical structure without independent bonding interfaces. The conductive layer can be printed from carbon-containing conductive paste and / or conductive metal paste, and can be mixed with conductive metal fillers to improve conductivity. This invention provides a self-supporting integrated electrode structure that can be peeled off entirely. It supports direct printing and construction on planar, curved, or non-planar three-dimensional substrates, patterning of battery functional areas, multi-unit series-parallel interconnection, and integration of the battery and circuitry within a reserved area on a substrate with circuit functional areas (e.g., a flexible printed circuit board), improving space utilization. This technology is suitable for flexible electronics, wearable devices, and micro-energy storage systems.

[0112] In summary, this invention forms a porous film layer by inducing phase separation through solvent evaporation, which enables ion transport and electronic isolation between adjacent electrode active layers. Furthermore, the porous film layer and the first and second electrode active layers are constructed through in-situ continuous film formation, resulting in continuous interfaces and reduced independent bonding interfaces. This effectively improves structural consistency and reduces interfacial impedance. The resulting integrated electrode maintains structural integrity and can exist as an independent electrochemical unit without relying on current collectors. It can also be used to fabricate integrated batteries and achieve patterned, modular interconnection and battery-circuit integration on the same substrate.

Claims

1. An integrated electrode, characterized in that, The integrated electrode comprises a first electrode active layer, a porous adhesive film layer, and a second electrode active layer stacked sequentially; the porous adhesive film layer is formed by solvent evaporation-induced phase separation of a polymer-based colloidal system; the polymer-based colloidal system comprises a polymer and a solvent; the polymer comprises at least one of polyamide, polyurethane, polyurea, polythiourea, or polyvinylidene fluoride polymers.

2. The integrated electrode according to claim 1, characterized in that, The porous adhesive film layer has a porous structure; the average pore size of the porous adhesive film layer is 0.05μm~10μm, and the average porosity is 20%~85%; And / or, the first electrode active layer is a positive electrode active layer or a negative electrode active layer, and the second electrode active layer is a negative electrode active layer or a positive electrode active layer corresponding to the first electrode active layer.

3. The integrated electrode according to claim 2, characterized in that, The positive electrode active layer contains a positive electrode active material, which includes at least one of lithium iron phosphate, layered oxide positive electrode material, or spinel type positive electrode material. And / or, the negative electrode active layer contains a negative electrode active material, which includes at least one of lithium titanate, graphite, or hard carbon material.

4. A method for preparing an integrated electrode as described in any one of claims 1 to 3, characterized in that, The method includes the following steps: preparing a first electrode active layer on the surface of a temporary substrate; applying the polymer solution to the surface of the first electrode active layer away from the temporary substrate, and forming the porous film layer by solvent evaporation-induced phase separation; preparing a second electrode active layer on the surface of the porous film layer away from the first electrode active layer; and removing the temporary substrate to obtain the integrated electrode.

5. An integrated battery, characterized in that, The integrated battery includes the integrated electrode as described in any one of claims 1 to 3.

6. The integrated battery according to claim 5, characterized in that, The integrated battery includes a battery substrate and battery cells disposed on the surface of the battery substrate; the battery cell includes a first conductive layer, the integrated electrode, and a second conductive layer stacked in sequence.

7. The integrated battery according to claim 6, characterized in that, The battery substrate is a planar substrate, a curved substrate, or a non-flat three-dimensional structure substrate; And / or, the battery substrate is made of at least one of wood, polymer, glass, ceramic, stone or brick. And / or, the raw materials for preparing the first conductive layer and / or the second conductive layer include conductive agents; the conductive agents include carbon materials and / or metal conductive fillers; the carbon materials include at least one of carbon black, graphite, graphene, or carbon nanotubes; the metal conductive fillers include at least one of silver, copper, nickel, or alloys thereof; And / or, the porous film layer of the integrated electrode is further provided with an electrolyte.

8. The integrated battery according to claim 6, characterized in that, The battery substrate includes a battery functional area, and the battery cell is disposed within the battery functional area; the planar projection pattern of the battery functional area includes at least one of the following: strip shape, snake shape, wave shape, spiral shape, grid shape, ring shape, text logo shape, or graphic logo shape; And / or, the number of battery cells is one or more; the multiple battery cells are connected in series and / or in parallel.

9. An electronic device, characterized in that, The electronic device includes a battery module and a functional module integrated on the same substrate; the battery module includes an integrated battery as described in any one of claims 5 to 8; the functional module includes conductive lines and / or electronic component interconnection structures.

10. The application of an integrated electrode as described in any one of claims 1 to 3, or an integrated battery as described in any one of claims 5 to 8, or the electronic device as described in claim 9 in the fabrication of flexible electronic devices, wearable electronic devices, or micro energy storage systems.

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